Pilot-model analysis and simulation study of effect of control task desired control response

Science.gov (United States)

Adams, J. J.; Gera, J.; Jaudon, J. B.

1978-01-01

A pilot model analysis was performed that relates pilot control compensation, pilot aircraft system response, and aircraft response characteristics for longitudinal control. The results show that a higher aircraft short period frequency is required to achieve superior pilot aircraft system response in an altitude control task than is required in an attitude control task. These results were confirmed by a simulation study of target tracking. It was concluded that the pilot model analysis provides a theoretical basis for determining the effect of control task on pilot opinions.

A case-control pilot study of low-intensity IVF in good-prognosis patients.

Science.gov (United States)

Gleicher, Norbert; Weghofer, Andrea; Barad, David H

2012-04-01

Low-intensity IVF (LI-IVF) is rapidly gaining in popularity. Yet studies comparing LI-IVF to standard IVF are lacking. This is a case-control pilot study, reporting on 14 first LI-IVF and 14 standard IVF cycles in women with normal age-specific ovarian reserve under age 38, matched for age, laboratory environment, staff and time of cycle. LI-IVF cycles underwent mild ovarian stimulation, utilizing clomiphene citrate, augmented by low-dose gonadotrophin stimulation. Control patients underwent routine ovarian stimulation. LI-IVF and regular IVF patients were similar in age, body mass index, FSH and anti-Müllerian hormone. Standard IVF utilized more gonadotrophins (PIVF demonstrated better odds for pregnancy (OR 7.07; P=0.046) and higher cumulative pregnancy rates (63.3% versus 21.4%; OR 6.6; P=0.02). Adjustments for age, ethnicity and diagnosis maintained significance but oocyte adjustment did not. Cost assessments failed to reveal differences between LI-IVF and standard IVF. In this small study, LI-IVF reduced pregnancy chances without demonstrating cost advantages, raising questions about its utility. In the absence of established clinical and/or economic foundations, LI-IVF should be considered an experimental procedure. Low-intensity IVF (LI-IVF) is increasingly propagated as an alternative to standard IVF. LI-IVF has, however, never been properly assessed in comparison to standard IVF. Such a comparison is presented in the format of a small pilot study, matching LI-IVF cycles with regular IVF cycles and comparing outcomes as well as costs. The study suggests that LI-IVF, at least in this setting, is clinically inferior and economically at best similar to standard IVF. LI-IVF should, therefore, as of this point not be offered as routine IVF treatment but only as an experimental procedure. Copyright © 2012 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Deficits in visuo-spatial but not in topographical memory during pregnancy and the postpartum state in an expert military pilot: a case report.

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Piccardi, Laura; Verde, Paola; Bianchini, Filippo; Morgagni, Fabio; Guariglia, Cecilia; Strollo, Felice; Tomao, Enrico

2014-08-13

It is well known that cognitive and emotional changes occur during pregnancy, but little is known about their magnitude or their time of occurrence and recovery. During pregnancy memory is one of the most impaired cognitive functions. Although long-term aspects of memory have been investigated, other aspects of memory have not yet been explored (i.e., navigational memory and reaching memory). Here we describe the changes in reaching and walking memory that occurred during pregnancy and one year after delivery in an Italian female military pilot (Case 1) with high spatial ability. In memory tests she showed a classical dissociation between performance in reaching and walking distance, which indicated a failure of working memory, learning, and storage in reaching space. This suggests that her expertise served as a protective factor mitigating her low walking memory performance, and saving the topographical component.We compared her performance with that of two non-pregnant control groups (i.e., women pilots and non-pilots) and found that Case 1's reaching memory performance was significantly worse than that of the control groups. Even one year postpartum, Case 1's performance was not yet the same as that of the other pilots. These findings contribute to our knowledge of the specific, as yet unexplored, aspects of memory deficits in women pilots during pregnancy and postpartum and suggest the need for better neuropsychological assessment before these women return to work in operational environments.

Tularemia Outbreak Investigation in Kosovo: Case Control and Environmental Studies

Science.gov (United States)

Dedushaj, Isuf; Gjini, Ardiana; Jorgensen, Tine Rikke; Cotter, Benvon; Lieftucht, Alfons; D’Ancona, Fortunato; Dennis, David T.; Kosoy, Michael A.; Mulliqi-Osmani, Gjyle; Grunow, Roland; Kalaveshi, Ariana; Gashi, Luljeta; Humolli, Isme

2002-01-01

A large outbreak of tularemia occurred in Kosovo in the early postwar period, 1999-2000. Epidemiologic and environmental investigations were conducted to identify sources of infection, modes of transmission, and household risk factors. Case and control status was verified by enzyme-linked immunosorbent assay, Western blot, and microagglutination assay. A total of 327 serologically confirmed cases of tularemia pharyngitis and cervical lymphadenitis were identified in 21 of 29 Kosovo municipalities. Matched analysis of 46 case households and 76 control households suggested that infection was transmitted through contaminated food or water and that the source of infection was rodents. Environmental circumstances in war-torn Kosovo led to epizootic rodent tularemia and its spread to resettled rural populations living under circumstances of substandard housing, hygiene, and sanitation. PMID:11749751

Keratoconus in Civil Aviation Pilots in a Report of Six Cases.

Science.gov (United States)

Rebello, Albert; Rodrigues, Bênesson; Pereira, Marcos

2017-06-01

Keratoconus is a progressive noninflammatory ectatic corneal dystrophy, characterized by corneal thinning and increased curvature with central or paracentral tapered protrusion. Such changes in corneal morphology induce irregular astigmatism and myopia, resulting in visual acuity impairment. This report assesses cases in which keratoconus is not an absolute disabling condition for civil aviation pilots. Six cases of keratoconus in active pilots are presented. This report includes cases which were treated with crosslinking therapy and even corneal transplantation. In such cases, the civil aviation medical authority considered four aspects in the medical assessment: best corrected visual acuity, condition stability, risk of sudden incapacitation, and pilot category. Six civil pilots with ages between 19 and 45 yr of age presented with keratoconus in different stages. Using the Snellen scale, best corrected visual acuity (BCVA) was measured in 12 eyes, all of them having equal or better than 20/30 (20/20, N = 9; 20/25, N = 2; 20/30, N = 1). All of them are currently fit for aviation activity and have been given an aviation medical certificate with limitation of use of corrective lenses by the Brazilian Civil Aviation Authority (ANAC in Portuguese). Among these cases, there is a pilot who had undergone treatment with crosslinking therapy and another that had undergone corneal transplantation. These cases demonstrate that keratoconus is not always a disabling condition for civil aviation pilots. Nevertheless, it has to be analyzed on a case-by-case basis.Rebello A, Rodrigues B, Pereira M. Keratoconus in civil aviation pilots in a report of six cases. Aerosp Med Hum Perform. 2017; 88(6):574-578.

Identification of Time-Varying Pilot Control Behavior in Multi-Axis Control Tasks

Science.gov (United States)

Zaal, Peter M. T.; Sweet, Barbara T.

2012-01-01

Recent developments in fly-by-wire control architectures for rotorcraft have introduced new interest in the identification of time-varying pilot control behavior in multi-axis control tasks. In this paper a maximum likelihood estimation method is used to estimate the parameters of a pilot model with time-dependent sigmoid functions to characterize time-varying human control behavior. An experiment was performed by 9 general aviation pilots who had to perform a simultaneous roll and pitch control task with time-varying aircraft dynamics. In 8 different conditions, the axis containing the time-varying dynamics and the growth factor of the dynamics were varied, allowing for an analysis of the performance of the estimation method when estimating time-dependent parameter functions. In addition, a detailed analysis of pilots adaptation to the time-varying aircraft dynamics in both the roll and pitch axes could be performed. Pilot control behavior in both axes was significantly affected by the time-varying aircraft dynamics in roll and pitch, and by the growth factor. The main effect was found in the axis that contained the time-varying dynamics. However, pilot control behavior also changed over time in the axis not containing the time-varying aircraft dynamics. This indicates that some cross coupling exists in the perception and control processes between the roll and pitch axes.

Nurse case-manager vs multifaceted intervention to improve quality of osteoporosis care after wrist fracture: randomized controlled pilot study.

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Majumdar, S R; Johnson, J A; Bellerose, D; McAlister, F A; Russell, A S; Hanley, D A; Garg, S; Lier, D A; Maksymowych, W P; Morrish, D W; Rowe, B H

2011-01-01

Few outpatients with fractures are treated for osteoporosis in the years following fracture. In a randomized pilot study, we found a nurse case-manager could double rates of osteoporosis testing and treatment compared with a proven efficacious quality improvement strategy directed at patients and physicians (57% vs 28% rates of appropriate care). Few patients with fractures are treated for osteoporosis. An intervention directed at wrist fracture patients (education) and physicians (guidelines, reminders) tripled osteoporosis treatment rates compared to controls (22% vs 7% within 6 months of fracture). More effective strategies are needed. We undertook a pilot study that compared a nurse case-manager to the multifaceted intervention using a randomized trial design. The case-manager counseled patients, arranged bone mineral density (BMD) tests, and prescribed treatments. We included controls from our first trial who remained untreated for osteoporosis 1-year post-fracture. Primary outcome was bisphosphonate treatment and secondary outcomes were BMD testing, appropriate care (BMD test-treatment if bone mass low), and costs. Forty six patients untreated 1-year after wrist fracture were randomized to case-manager (n = 21) or multifaceted intervention (n = 25). Median age was 60 years and 68% were female. Six months post-randomization, 9 (43%) case-managed patients were treated with bisphosphonates compared with 3 (12%) multifaceted intervention patients (relative risk [RR] 3.6, 95% confidence intervals [CI] 1.1-11.5, p = 0.019). Case-managed patients were more likely than multifaceted intervention patients to undergo BMD tests (81% vs 52%, RR 1.6, 95%CI 1.1-2.4, p = 0.042) and receive appropriate care (57% vs 28%, RR 2.0, 95%CI 1.0-4.2, p = 0.048). Case-management cost was $44 (CDN) per patient vs $12 for the multifaceted intervention. A nurse case-manager substantially increased rates of appropriate testing and treatment for osteoporosis in

Clinical and psychological features of normal-weight women with subthreshold anorexia nervosa: a pilot case-control observational study.

Science.gov (United States)

Tagliabue, Anna; Ferraris, Cinzia; Martinelli, Valentina; Pinelli, Giovanna; Repossi, Ilaria; Trentani, Claudia

2012-01-01

Weight preoccupations have been frequently reported in normal-weight subjects. Subthreshold anorexia nervosa (s-AN, all DSM IV TR criteria except amenorrhea or underweight) is a form of eating disorder not otherwise specified that has received scarce scientific attention. Under a case-control design we compared the general characteristics, body composition, and psychopathological features of normal-weight patients with s-AN with those of BMI- and sex-matched controls. Participants in this pilot study included 9 normal-weight women who met the DSM IV TR criteria for s-AN and 18 BMI-matched normal-weight controls. The general characteristics of the study participants were collected by questionnaire. Body composition was measured by bioelectrical impedance. Behavioral and psychological measures included the standardized symptom checklist (SCL-90-R) and the eating disorder inventory (EDI-2). There were no differences in age, education, employment status, marital status, and history of previous slimming treatment in the two study groups. In addition, anthropometric measures and body composition of s-AN patients and BMI-matched normal weight controls were not significantly different. In the s-AN subgroup, we found a significant relationship between waist circumference and the SCL-90-R obsessivity-compulsivity scale (n=9, r=-0.69, pstudy cohort. These pilot results suggest that psychopathological criteria (particularly related to the obsessivity-compulsivity dimension) may be more useful than anthropometric measures for screening of s-AN in normal-weight women.

Linkage to care among adults being investigated for tuberculosis in South Africa: pilot study of a case manager intervention.

Science.gov (United States)

Maraba, Noriah; Chihota, Violet; McCarthy, Kerrigan; Churchyard, Gavin J; Grant, Alison D

2018-05-24

We piloted an intervention to determine if support from a case manager would assist adults being investigated for tuberculosis (TB) to link into TB and HIV care. Pilot interventional cohort study. Patients identified by primary healthcare clinic staff in South Africa as needing TB investigations were enrolled. Participants were supported for 3 months by case managers who facilitated the care pathway by promoting HIV testing, getting laboratory results, calling patients to return for results and facilitating treatment initiation. Linkage to TB care was defined as starting TB treatment within 28 days in those with a positive test result; linkage to HIV care, for HIV-positive people, was defined as having blood taken for CD4 count and, for those eligible, starting antiretroviral therapy within 3 months. Intervention implementation was measured by number of attempts to contact participants. Among 562 participants (307 (54.6%) female, median age: 36 years (IQR 29-44)), most 477 (84.8%) had previously tested for HIV; of these, 328/475 (69.1%) self-reported being HIV-positive. Overall, 189/562 (33.6%) participants needed linkage to care (132 HIV care linkage only; 35 TB treatment linkage only; 22 both). Of 555 attempts to contact these 189 participants, 407 were to facilitate HIV care linkage, 78 for TB treatment linkage and 70 for both. At the end of 3-month follow-up, 40 participants had not linked to care (29 of the 132 (22.0%) participants needing linkage to HIV care only, 4 of the 35 (11.4%) needing to start on TB treatment only and 7 of the 22 (31.8%) needing both). Many people testing for TB need linkage to care. Despite case manager support, non-linkage into HIV care remained higher than desirable, suggesting a need to modify this intervention before implementation. Innovative strategies to enable linkage to care are needed. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial

Is case-chaos methodology an appropriate alternative to conventional case-control studies for investigating outbreaks?

Science.gov (United States)

Edelstein, Michael; Wallensten, Anders; Kühlmann-Berenzon, Sharon

2014-08-15

Case-chaos methodology is a proposed alternative to case-control studies that simulates controls by randomly reshuffling the exposures of cases. We evaluated the method using data on outbreaks in Sweden. We identified 5 case-control studies from foodborne illness outbreaks that occurred between 2005 and 2012. Using case-chaos methodology, we calculated odds ratios 1,000 times for each exposure. We used the median as the point estimate and the 2.5th and 97.5th percentiles as the confidence interval. We compared case-chaos matched odds ratios with their respective case-control odds ratios in terms of statistical significance. Using Spearman's correlation, we estimated the correlation between matched odds ratios and the proportion of cases exposed to each exposure and quantified the relationship between the 2 using a normal linear mixed model. Each case-control study identified an outbreak vehicle (odds ratios = 4.9-45). Case-chaos methodology identified the outbreak vehicle 3 out of 5 times. It identified significant associations in 22 of 113 exposures that were not associated with outcome and 5 of 18 exposures that were significantly associated with outcome. Log matched odds ratios correlated with their respective proportion of cases exposed (Spearman ρ = 0.91) and increased significantly with the proportion of cases exposed (b = 0.054). Case-chaos methodology missed the outbreak source 2 of 5 times and identified spurious associations between a number of exposures and outcome. Measures of association correlated with the proportion of cases exposed. We recommended against using case-chaos analysis during outbreak investigations. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Controlled pilot oxidizer for a gas turbine combustor

Science.gov (United States)

Laster, Walter R.; Bandaru, Ramarao V.

2010-07-13

A combustor (22) for a gas turbine (10) includes a main burner oxidizer flow path (34) delivering a first portion (32) of an oxidizer flow (e.g., 16) to a main burner (28) of the combustor and a pilot oxidizer flow path (38) delivering a second portion (36) of the oxidizer flow to a pilot (30) of the combustor. The combustor also includes a flow controller (42) disposed in the pilot oxidizer flow path for controlling an amount of the second portion delivered to the pilot.

A pilot rating scale for evaluating failure transients in electronic flight control systems

Science.gov (United States)

Hindson, William S.; Schroeder, Jeffery A.; Eshow, Michelle M.

1990-01-01

A pilot rating scale was developed to describe the effects of transients in helicopter flight-control systems on safety-of-flight and on pilot recovery action. The scale was applied to the evaluation of hardovers that could potentially occur in the digital flight-control system being designed for a variable-stability UH-60A research helicopter. Tests were conducted in a large moving-base simulator and in flight. The results of the investigation were combined with existing airworthiness criteria to determine quantitative reliability design goals for the control system.

Hospital branding in Italy: A pilot study based on the case method.

Science.gov (United States)

Esposito, Annamaria

2017-01-01

The article investigates if, and in affirmative case how, Italian hospitals are managing corporate brand communication. Thanks to results of qualitative research, this article offers insights on Italian hospital branding. The pilot study based in the case method is to be considered a starting point for wider investigations on this topic, and it is useful for managers and practitioners who want to understand the role of corporate brand in hospital communication management and to connect health care professionals with the audience in a meaningful way in those countries in which the health care system is a mix of both public and private institutions.

Launch Vehicle Manual Steering with Adaptive Augmenting Control In-flight Evaluations Using a Piloted Aircraft

Science.gov (United States)

Hanson, Curt

2014-01-01

An adaptive augmenting control algorithm for the Space Launch System has been developed at the Marshall Space Flight Center as part of the launch vehicles baseline flight control system. A prototype version of the SLS flight control software was hosted on a piloted aircraft at the Armstrong Flight Research Center to demonstrate the adaptive controller on a full-scale realistic application in a relevant flight environment. Concerns regarding adverse interactions between the adaptive controller and a proposed manual steering mode were investigated by giving the pilot trajectory deviation cues and pitch rate command authority.

Output-Feedback Model Predictive Control of a Pasteurization Pilot Plant based on an LPV model

Science.gov (United States)

Karimi Pour, Fatemeh; Ocampo-Martinez, Carlos; Puig, Vicenç

2017-01-01

This paper presents a model predictive control (MPC) of a pasteurization pilot plant based on an LPV model. Since not all the states are measured, an observer is also designed, which allows implementing an output-feedback MPC scheme. However, the model of the plant is not completely observable when augmented with the disturbance models. In order to solve this problem, the following strategies are used: (i) the whole system is decoupled into two subsystems, (ii) an inner state-feedback controller is implemented into the MPC control scheme. A real-time example based on the pasteurization pilot plant is simulated as a case study for testing the behavior of the approaches.

Data-linked pilot reply time on controller workload and communication in a simulated terminal option

Science.gov (United States)

2001-05-01

This report describes an analysis of air traffic control communication and workload in a simulated terminal radar approach : control environment. The objective of this study was to investigate how pilot-to-controller data-link acknowledgment time : m...

Vascular anomalies in the mesenteric circulation of patients with Crohn’s disease: a pilot study

Directory of Open Access Journals (Sweden)

Matilde Zamboni

2017-07-01

Full Text Available Crohn’s disease (CD is a chronic inflammatory bowel disease and its pathogenesis is still not well understood. Previous studies suggested the possibility of the involvement of vascular system, but, todate, the mesenteric circulation has poor been investigated, especially in complicated CD cases requiring colectomy. We investigated the mesenteric circulation in a case-control pilot study, including 19 controls and 7 patients affected by complicated cases of CD. Cases and controls underwent selective angiography of both superior and inferior mesenteric district. Transit time was found either significantly shortened in 2/7 cases (29%, or prolonged 5/7 (71% (P=0.0034 in the superior mesenteric district; P=0.0079 in the inferior mesenteric district, respectively due to the presence of A-V malformations and of a miscellaneous of venous abnormalities, which included thrombosis, hypoplasia and extra-truncular venous malformations. Our study demonstrates the presence of congenital or acquired vascular anomalies in a small sample of CD patients not responder to current treatment and with severe complications. The present pilot study warrants further investigations.

Outbreak of Salmonella Enteritidis phage type 13a: case-control investigation in Hertsmere, United Kingdom.

Science.gov (United States)

Morgan, O; Milne, L; Kumar, S; Murray, D; Man, W; Georgiou, M; Verlander, N Q; de Pinna, E; McEvoy, M

2007-07-01

Cases of illness were reported to Hertsmere Borough Council among attendees of a children's charity event in June 2006. Initial laboratory investigation identified Salmonella Enteritidis PT13a as a possible cause of the outbreak. We carried out an unmatched case-control investigation. The population at risk included all individuals who attended the event. Self-completion questionnaires were sent to 53 presumptive cases and 212 randomly selected potential controls. Information was available for 49 cases and 128 controls (overall response rate=75%). We calculated odds ratios from single and multivariable analysis and tested for all two-way interactions. Risk factors for diarrhoea were eating egg mayonnaise bagels (OR=34.1, 95%CI 10.5 - 111.3) and drinking apple juice (OR=16.1, 95% CI 3.5 - 74.2). There was weak statistical evidence to suggest that the risk of diarrhoea after eating egg mayonnaise bagels was greater in the afternoon. No food samples were available to confirm which food item might have caused this outbreak. Eggs from Spain were used by the caterer. The ecology of salmonella, experience from previous outbreaks and epidemiological findings from this case-control investigation suggest that the most likely cause of the outbreak was contaminated eggs.

BWR control rod drive scram pilot valve monitoring system

International Nuclear Information System (INIS)

Soden, R.A.; Kelly, V.

1984-01-01

The control rod drive system in a Boiling Water Reactor is the most important safety system in the power plant. All components of the system can be verified except the solenoid operated, scram pilot valves without scramming a rod. The pilot valve mechancial works is the weak link to the control rod drive system. These pilot valves control the hydraulic system which applies pressure to the ''insert'' side of the control rod piston and vents the ''withdraw'' side of the piston causing the rods to insert during a scam. The only verification that the valve is operating properly is to scram the rod. The concern for this portion of the system is demonstrated by the high number of redundant components and complete periodic testing of the electrical circuits. The pilot valve can become hung-up through wear, fracture of internal components, mechanical binding, foreign material or chemicals left in the valve during maintenance, etc. If the valve becomes hung-up the electrical tests performed will not indicate this condition and scramming the rod is in jeopardy. Only an attempt to scram a rod will indicate the hung-up valve. While this condition exists the rod is considered inoperative. This paper describes a system developed at a nuclear power plant that monitors the pilot valves on the control rod drive system. This system utilizes pattern recognition to assure proper internal workings of the scram pilot valves to plant operators. The system is totally automatic such that each time the valve is operated on a ''half scram'', a printout is available to the operator along with light indication that each of the 370 valves (on one unit of a BWR) is operating properly. With this monitoring system installed, all components of the control rod drive system including the solenoid pilot valves can be verified as operational without scramming any rods

BWR control rod drive scram pilot valve monitoring program

International Nuclear Information System (INIS)

Soden, R.A.; Kelly, V.

1986-01-01

The control rod drive system in a Boiling Water Reactor is the most important safety system in the power plant. All components of the system can be verified except the solenoid operated, scram pilot valves without scramming a rod. The pilot valve mechanical works is the weak link to the control rod drive system. These pilot valves control the hydraulic system which applies pressure to the insert side of the control rod piston and vents the withdraw side of the piston causing the rods to insert during a scram. The only verification that the valve is operating properly is to scram the rod. The concern for this portion of the system is demonstrated by the high number of redundant components and complete periodic testing of the electrical circuits. The pilot valve can become hung-up through wear, fracture of internal components, mechanical binding, foreign material or chemicals left in the valve during maintenance, etc. If the valve becomes hung-up the electrical tests performed will not indicate this condition and scramming the rod is in jeopardy. Only an attempt to scram a rod will indicate the hung-up valve. While this condition exists the rod is considered inoperative. This paper describes a system developed at a nuclear power plant that monitors the pilot valves on the control rod drive system. This system utilizes pattern recognition to assure proper internal workings of the scram pilot valves to plant operators. The system is totally automatic such that each time the valve is operated on a half scram, a printout is available to the operator along with light indication that each of the 370 valves (on one unit of a BWR) is operating properly. With this monitoring system installed, all components of the control rod drive system including the solenoid pilot valves can be verified as operational without scramming any rods

Launch Vehicle Manual Steering with Adaptive Augmenting Control In-flight Evaluations of Adverse Interactions Using a Piloted Aircraft

Science.gov (United States)

Hanson, Curt; Miller, Chris; Wall, John H.; Vanzwieten, Tannen S.; Gilligan, Eric; Orr, Jeb S.

2015-01-01

An adaptive augmenting control algorithm for the Space Launch System has been developed at the Marshall Space Flight Center as part of the launch vehicles baseline flight control system. A prototype version of the SLS flight control software was hosted on a piloted aircraft at the Armstrong Flight Research Center to demonstrate the adaptive controller on a full-scale realistic application in a relevant flight environment. Concerns regarding adverse interactions between the adaptive controller and a proposed manual steering mode were investigated by giving the pilot trajectory deviation cues and pitch rate command authority. Two NASA research pilots flew a total of twenty five constant pitch-rate trajectories using a prototype manual steering mode with and without adaptive control.

Impacts of safety on the design of light remotely-piloted helicopter flight control systems

International Nuclear Information System (INIS)

Di Rito, G.; Schettini, F.

2016-01-01

This paper deals with the architecture definition and the safety assessment of flight control systems for light remotely-piloted helicopters for civil applications. The methods and tools to be used for these activities are standardised for conventional piloted aircraft, while they are currently a matter of discussion in case of light remotely-piloted systems flying into unsegregated airspaces. Certification concerns are particularly problematic for aerial systems weighing from 20 to 150 kgf, since the airworthiness permission is granted by national authorities. The lack of specific requirements actually requires to analyse both the existing standards for military applications and the certification guidelines for civil systems, up to derive the adequate safety objectives. In this work, after a survey on applicable certification documents for the safety objectives definition, the most relevant functional failures of a light remotely-piloted helicopter are identified and analysed via Functional Hazard Assessment. Different architectures are then compared by means of Fault-Tree Analysis, highlighting the contributions to the safety level of the main elements of the flight control system (control computers, servoactuators, antenna) and providing basic guidelines on the required redundancy level. - Highlights: • A method for architecture definition and safety assessment of light RW‐UAS flight control systems is proposed. • Relevant UAS failures are identified and analysed via Functional Hazard Assessment and Fault‐Tree Analysis. • The key safety elements are control computers, servoactuators and TX/RX system. • Single‐simplex flight control systems have inadequate safety levels. • Dual‐duplex flight control systems demonstrate to be safety compliant, with safety budgets dominated by servoactuators.

Cognitive and physical rehabilitation of intensive care unit survivors: results of the RETURN randomized controlled pilot investigation.

Science.gov (United States)

Jackson, James C; Ely, E Wesley; Morey, Miriam C; Anderson, Venice M; Denne, Laural B; Clune, Jennifer; Siebert, Carol S; Archer, Kristin R; Torres, Renee; Janz, David; Schiro, Elena; Jones, Julie; Shintani, Ayumi K; Levine, Brian; Pun, Brenda T; Thompson, Jennifer; Brummel, Nathan E; Hoenig, Helen

2012-04-01

Millions of patients who survive medical and surgical general intensive care unit care every year experience newly acquired long-term cognitive impairment and profound physical and functional disabilities. To overcome the current reality in which patients receive inadequate rehabilitation, we devised a multifaceted, in-home, telerehabilitation program implemented using social workers and psychology technicians with the goal of improving cognitive and functional outcomes. This was a single-site, feasibility, pilot, randomized trial of 21 general medical/surgical intensive care unit survivors (8 controls and 13 intervention patients) with either cognitive or functional impairment at hospital discharge. After discharge, study controls received usual care (sporadic rehabilitation), whereas intervention patients received a combination of in-home cognitive, physical, and functional rehabilitation over a 3-month period via a social worker or master's level psychology technician utilizing telemedicine to allow specialized multidisciplinary treatment. Interventions over 12 wks included six in-person visits for cognitive rehabilitation and six televisits for physical/functional rehabilitation. Outcomes were measured at the completion of the rehabilitation program (i.e., at 3 months), with cognitive functioning as the primary outcome. Analyses were conducted using linear regression to examine differences in 3-month outcomes between treatment groups while adjusting for baseline scores. Patients tolerated the program with only one adverse event reported. At baseline both groups were well-matched. At 3-month follow-up, intervention group patients demonstrated significantly improved cognitive executive functioning on the widely used and well-normed Tower test (for planning and strategic thinking) vs. controls (median [interquartile range], 13.0 [11.5-14.0] vs. 7.5 [4.0-8.5]; adjusted p improving cognitive performance and functional outcomes in just 3 months. Future investigations

Evaluating the benefits of a youth mental health curriculum for students in Nicaragua: a parallel-group, controlled pilot investigation.

Science.gov (United States)

Ravindran, Arun V; Herrera, Andres; da Silva, Tricia L; Henderson, Joanna; Castrillo, Magda Esther; Kutcher, Stan

2018-01-01

High rates of mental illness and addictions are well documented among youth in Nicaragua. Limited mental health services, poor mental health knowledge and stigma reduce help-seeking. The Mental Health Curriculum (MHC) is a Canadian school-based program that has shown a positive impact on such contributing factors. This pilot project evaluated the impact of the MHC on mental wellness and functioning among youth in Leon, Nicaragua. High school and university students (aged 14-25 years) were assigned to intervention (12-week MHC; n   =  567) and control (wait-list; n   =  346) groups in a non-randomized design. Both groups completed measures of mental health knowledge, stigma and function at baseline and 12 weeks. Multivariate analyses and repeated measures analyses were used to compare group outcomes. At baseline, intervention students showed higher substance use (mean difference [MD]  =  0.24) and lower perceived stress (MD = -1.36) than controls ( p   mental health knowledge (MD  =  1.75), lower stigma (MD  =  1.78), more adaptive coping (MD  =  0.82), better lifestyle choices (MD  =  0.06) and lower perceived stress (MD = -1.63) ( p   mental health knowledge, small to moderate for stigma and modest for the other variables. Substance use also decreased among intervention students to similar levels as controls (MD  =  0.03) ( p  > 0.05). This pilot investigation demonstrates the benefits of the MHC in a low-and-middle-income youth population. The findings replicate results found in Canadian student populations and support its cross-cultural applicability.

Pilot and Controller Evaluations of Separation Function Allocation in Air Traffic Management

Science.gov (United States)

Wing, David; Prevot, Thomas; Morey, Susan; Lewis, Timothy; Martin, Lynne; Johnson, Sally; Cabrall, Christopher; Como, Sean; Homola, Jeffrey; Sheth-Chandra, Manasi; style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20130014930'); toggleEditAbsImage('author_20130014930_show'); toggleEditAbsImage('author_20130014930_hide'); "> style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20130014930_show"> style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20130014930_hide">

2013-01-01

Two human-in-the-loop simulation experiments were conducted in coordinated fashion to investigate the allocation of separation assurance functions between ground and air and between humans and automation. The experiments modeled a mixed-operations concept in which aircraft receiving ground-based separation services shared the airspace with aircraft providing their own separation service (i.e., self-separation). Ground-based separation was provided by air traffic controllers without automation tools, with tools, or by ground-based automation with controllers in a managing role. Airborne self-separation was provided by airline pilots using self-separation automation enabled by airborne surveillance technology. The two experiments, one pilot-focused and the other controller-focused, addressed selected key issues of mixed operations, assuming the starting point of current-day operations and modeling an emergence of NextGen technologies and procedures. In the controller-focused experiment, the impact of mixed operations on controller performance was assessed at four stages of NextGen implementation. In the pilot-focused experiment, the limits to which pilots with automation tools could take full responsibility for separation from ground-controlled aircraft were tested. Results indicate that the presence of self-separating aircraft had little impact on the controllers' ability to provide separation services for ground-controlled aircraft. Overall performance was best in the most automated environment in which all aircraft were data communications equipped, ground-based separation was highly automated, and self-separating aircraft had access to trajectory intent information for all aircraft. In this environment, safe, efficient, and highly acceptable operations could be achieved for twice today's peak airspace throughput. In less automated environments, reduced trajectory intent exchange and manual air traffic control limited the safely achievable airspace throughput and

Task-Oriented and Relationship-Building Communications between Air Traffic Controllers and Pilots

Directory of Open Access Journals (Sweden)

Inwon Kang

2017-09-01

Full Text Available By questioning the lopsided attention on task-oriented factors in air traffic controller-pilot communication, the current study places an equal weighting on both task-oriented and relationship-building communications, and investigates how each type of communication influences sustainable performance in airline operation team. Results show that both task-oriented and relationship-building communications in terms of sustainability of team process predicted greater communication satisfaction at work. Also, both task interdependence and shared leadership influenced both types of air traffic controller-pilot communication. However, only relationship-building communication had a direct influence on perceived work performance whereas task-oriented communication had not. Along with task-oriented factors, this study raises the relationship-oriented factors as important resources for the sustainable team performance in airline industry.

Pilot-in-the-Loop Analysis of Propulsive-Only Flight Control Systems

Science.gov (United States)

Chou, Hwei-Lan; Biezad, Daniel J.

1996-01-01

Longitudinal control system architectures are presented which directly couple flight stick motions to throttle commands for a multi-engine aircraft. This coupling enables positive attitude control with complete failure of the flight control system. The architectures chosen vary from simple feedback gains to classical lead-lag compensators with and without prefilters. Each architecture is reviewed for its appropriateness for piloted flight. The control systems are then analyzed with pilot-in-the-loop metrics related to bandwidth required for landing. Results indicate that current and proposed bandwidth requirements should be modified for throttles only flight control. Pilot ratings consistently showed better ratings than predicted by analysis. Recommendations are made for more robust design and implementation. The use of Quantitative Feedback Theory for compensator design is discussed. Although simple and effective augmented control can be achieved in a wide variety of failed configurations, a few configuration characteristics are dominant for pilot-in-the-loop control. These characteristics will be tested in a simulator study involving failed flight controls for a multi-engine aircraft.

Occupational Stress and Hypertension among Railway Loco Pilots and Section Controllers

Science.gov (United States)

Jayakumar, Devasigamoney

2017-01-01

Introduction: A cross-sectional study on occupational stress was conducted on loco pilots in 2008, in view of loco pilots being one of the high strain jobs in Indian Railways. Subsequently, a comparative cross-sectional study on occupational stress was conducted among section controllers in 2011, which is another high strain job of Indian Railways. Objective: The studies were conducted to analyze and compare occupational stress and hypertension. Setting and Design: A cross-sectional study on occupational stress and hypertension was conducted among 230 loco pilots in 2008, and subsequently, a comparative cross-sectional study was conducted among 82 section controllers in 2011. Materials and Methods: A closed end 24 item questionnaire on occupational stress was administered. Systolic blood pressure above 140 mmHg and diastolic blood pressure above 90 mmHg were considered as hypertension as per the VII Joint National Committee. Chi-square test and t-test were used for testing significance at P < 0.05. Results: The mean stress score was 8.56 in loco pilots and 7.32 in section controllers. The number of loco pilots with more than 12 stress factors was 49 (21.3%) and the number of section controllers with more than 12 stress factors was 7 (8.5%). The number employees with more than 12 stress factors in different categories of loco pilots were 30 (32%) in the goods category, 12 (12%) in the mail/passenger category, and 7 (19%) in the shunter category, and 3 (11%) in the supervisory category and 4 (7%) in the on-board category of section controllers. The prevalence of hypertension in loco pilots was 36.52% (84) and in the section controllers was 53.66% (44). The prevalence of hypertension in the category with more than 12 stress factors was 30.61% (15) in the loco pilots and 28.57% (2) in the section controllers. The prevalence of hypertension in the both the study groups were higher in the older age, with a family history of hypertension, and with a body mass index of

Occupational Stress and Hypertension among Railway Loco Pilots and Section Controllers.

Science.gov (United States)

Jayakumar, Devasigamoney

2017-01-01

A cross-sectional study on occupational stress was conducted on loco pilots in 2008, in view of loco pilots being one of the high strain jobs in Indian Railways. Subsequently, a comparative cross-sectional study on occupational stress was conducted among section controllers in 2011, which is another high strain job of Indian Railways. The studies were conducted to analyze and compare occupational stress and hypertension. A cross-sectional study on occupational stress and hypertension was conducted among 230 loco pilots in 2008, and subsequently, a comparative cross-sectional study was conducted among 82 section controllers in 2011. A closed end 24 item questionnaire on occupational stress was administered. Systolic blood pressure above 140 mmHg and diastolic blood pressure above 90 mmHg were considered as hypertension as per the VII Joint National Committee. Chi-square test and t -test were used for testing significance at P stress score was 8.56 in loco pilots and 7.32 in section controllers. The number of loco pilots with more than 12 stress factors was 49 (21.3%) and the number of section controllers with more than 12 stress factors was 7 (8.5%). The number employees with more than 12 stress factors in different categories of loco pilots were 30 (32%) in the goods category, 12 (12%) in the mail/passenger category, and 7 (19%) in the shunter category, and 3 (11%) in the supervisory category and 4 (7%) in the on-board category of section controllers. The prevalence of hypertension in loco pilots was 36.52% (84) and in the section controllers was 53.66% (44). The prevalence of hypertension in the category with more than 12 stress factors was 30.61% (15) in the loco pilots and 28.57% (2) in the section controllers. The prevalence of hypertension in the both the study groups were higher in the older age, with a family history of hypertension, and with a body mass index of more than 25 kg/m 2 . The mean occupational stress and employees with more than 12 stress

Piloted Simulation Tests of Propulsion Control as Backup to Loss of Primary Flight Controls for a B747-400 Jet Transport

Science.gov (United States)

Bull, John; Mah, Robert; Hardy, Gordon; Sullivan, Barry; Jones, Jerry; Williams, Diane; Soukup, Paul; Winters, Jose

1997-01-01

Partial failures of aircraft primary flight control systems and structural damages to aircraft during flight have led to catastrophic accidents with subsequent loss of lives (e.g. DC-10, B-747, C-5, B-52, and others). Following the DC-10 accident at Sioux City, Iowa in 1989, the National Transportation Safety Board recommended 'Encourage research and development of backup flight control systems for newly certified wide-body airplanes that utilize an alternate source of motive power separate from that source used for the conventional control system.' This report describes the concept of a propulsion controlled aircraft (PCA), discusses pilot controls, displays, and procedures; and presents the results of a PCA piloted simulation test and evaluation of the B747-400 airplane conducted at NASA Ames Research Center in December, 1996. The purpose of the test was to develop and evaluate propulsion control throughout the full flight envelope of the B747-400 including worst case scenarios of engine failures and out of trim moments. Pilot ratings of PCA performance ranged from adequate to satisfactory. PCA performed well in unusual attitude recoveries at 35,000 ft altitude, performed well in fully coupled ILS approaches, performed well in single engine failures, and performed well at aft cg. PCA performance was primarily limited by out-of-trim moments.

A pilot randomized, controlled trial of metformin versus insulin in women with type 2 diabetes mellitus during pregnancy.

Science.gov (United States)

Refuerzo, Jerrie S; Gowen, Rose; Pedroza, Claudia; Hutchinson, Maria; Blackwell, Sean C; Ramin, Susan

2015-02-01

Few studies support oral diabetic treatment in pregnant women with type 2 diabetes mellitus (T2DM). The objective of this study was to compare the effects of metformin versus insulin on achieving glycemic control and improving maternal and neonatal outcomes in pregnant women with T2DM. A pilot randomized, controlled trial was conducted of metformin versus insulin for the treatment of T2DM during pregnancy. The primary outcome was glycemic control measured with hemoglobin A1c metformin and 11 received insulin. All women in both groups achieved glycemic control by delivery (HgbA1c: metformin 5.96 ± 5.88 vs. insulin 6.34 ± 0.92%). There were similar rates of cesarean delivery, birth weights, neonatal intensive care unit admissions, respiratory distress syndrome, and neonatal dextrose treatment between groups. There was one case of fetal macrosomia in the insulin group, one case of shoulder dystocia in the metformin group and no cases of failed metformin therapy. In this pilot study, glycemic control was achieved in women who received metformin and insulin. Larger studies are needed to determine whether metformin can be considered a reasonable alternative to insulin in pregnant women with T2DM. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Predicting Loss-of-Control Boundaries Toward a Piloting Aid

Science.gov (United States)

Barlow, Jonathan; Stepanyan, Vahram; Krishnakumar, Kalmanje

2012-01-01

This work presents an approach to predicting loss-of-control with the goal of providing the pilot a decision aid focused on maintaining the pilot's control action within predicted loss-of-control boundaries. The predictive architecture combines quantitative loss-of-control boundaries, a data-based predictive control boundary estimation algorithm and an adaptive prediction method to estimate Markov model parameters in real-time. The data-based loss-of-control boundary estimation algorithm estimates the boundary of a safe set of control inputs that will keep the aircraft within the loss-of-control boundaries for a specified time horizon. The adaptive prediction model generates estimates of the system Markov Parameters, which are used by the data-based loss-of-control boundary estimation algorithm. The combined algorithm is applied to a nonlinear generic transport aircraft to illustrate the features of the architecture.

RodPilotR - The Innovative and Cost-Effective Digital Control Rod Drive Control System for PWRs

International Nuclear Information System (INIS)

Baron, Clemens

2008-01-01

With RodPilot, AREVA NP offers an innovative and cost-effective system for controlling control rods in Pressurized Water Reactors. RodPilot controls the three operating coils of the control rod drive mechanism (lift, moveable gripper and stationary gripper coil). The rods are inserted into or withdrawn from the core as required by the Reactor Control System. The system combines modern components, state-of-the-art logic and a proven electronic control rod drive control principle to provide enhanced reliability and lower maintenance costs. (author)

Combining control input with flight path data to evaluate pilot performance in transport aircraft.

Science.gov (United States)

Ebbatson, Matt; Harris, Don; Huddlestone, John; Sears, Rodney

2008-11-01

When deriving an objective assessment of piloting performance from flight data records, it is common to employ metrics which purely evaluate errors in flight path parameters. The adequacy of pilot performance is evaluated from the flight path of the aircraft. However, in large jet transport aircraft these measures may be insensitive and require supplementing with frequency-based measures of control input parameters. Flight path and control input data were collected from pilots undertaking a jet transport aircraft conversion course during a series of symmetric and asymmetric approaches in a flight simulator. The flight path data were analyzed for deviations around the optimum flight path while flying an instrument landing approach. Manipulation of the flight controls was subject to analysis using a series of power spectral density measures. The flight path metrics showed no significant differences in performance between the symmetric and asymmetric approaches. However, control input frequency domain measures revealed that the pilots employed highly different control strategies in the pitch and yaw axes. The results demonstrate that to evaluate pilot performance fully in large aircraft, it is necessary to employ performance metrics targeted at both the outer control loop (flight path) and the inner control loop (flight control) parameters in parallel, evaluating both the product and process of a pilot's performance.

Radiographic Measurements of the Affected and Unaffected Feet in Patients with Unilateral Hallux Limitus A Case-Control Pilot Study.

Science.gov (United States)

Knox, Andrew F; Bryant, Alan R

2016-05-01

Controversy exists regarding the structural and functional causes of hallux limitus, including metatarsus primus elevatus, a long first metatarsal, first-ray hypermobility, the shape of the first metatarsal head, and the presence of hallux interphalangeus. Some articles have reported on the radiographic evaluation of these measurements in feet affected by hallux limitus, but no study has directly compared the affected and unaffected feet in patients with unilateral hallux limitus. This case-control pilot study aimed to establish whether any such differences exist. Dorsoplantar and lateral weightbearing radiographs of both feet in 30 patients with unilateral hallux limitus were assessed for grade of disease, lateral intermetatarsal angle, metatarsal protrusion distance, plantar gapping at the first metatarsocuneiform joint, metatarsal head shape, and hallux abductus interphalangeus angle. Data analysis was performed using a statistical software program. Mean radiographic measurements for affected and unaffected feet demonstrated that metatarsus primus elevatus, a short first metatarsal, first-ray hypermobility, a flat metatarsal head shape, and hallux interphalangeus were prevalent in both feet. There was no statistically significant difference between feet for any of the radiographic parameters measured (Mann-Whitney U tests, independent-samples t tests, and Pearson χ(2) tests: P > .05). No significant differences exist in the presence of the structural risk factors examined between affected and unaffected feet in patients with unilateral hallux limitus. The influence of other intrinsic factors, including footedness and family history, should be investigated further.

RodPilot{sup R} - The Innovative and Cost-Effective Digital Control Rod Drive Control System for PWRs

Energy Technology Data Exchange (ETDEWEB)

Baron, Clemens [AREVA NP GmbH, NLEE-G, Postfach 1199, 91001 Erlangen (Germany)

2008-07-01

With RodPilot, AREVA NP offers an innovative and cost-effective system for controlling control rods in Pressurized Water Reactors. RodPilot controls the three operating coils of the control rod drive mechanism (lift, moveable gripper and stationary gripper coil). The rods are inserted into or withdrawn from the core as required by the Reactor Control System. The system combines modern components, state-of-the-art logic and a proven electronic control rod drive control principle to provide enhanced reliability and lower maintenance costs. (author)

Online market research panel members as controls in case-control studies to investigate gastrointestinal disease outbreaks: early experiences and lessons learnt from the UK.

Science.gov (United States)

Mook, P; McCormick, J; Kanagarajah, S; Adak, G K; Cleary, P; Elson, R; Gobin, M; Hawker, J; Inns, T; Sinclair, C; Trienekens, S C M; Vivancos, R; McCarthy, N D

2018-03-01

Established methods of recruiting population controls for case-control studies to investigate gastrointestinal disease outbreaks can be time consuming, resulting in delays in identifying the source or vehicle of infection. After an initial evaluation of using online market research panel members as controls in a case-control study to investigate a Salmonella outbreak in 2013, this method was applied in four further studies in the UK between 2014 and 2016. We used data from all five studies and interviews with members of each outbreak control team and market research panel provider to review operational issues, evaluate risk of bias in this approach and consider methods to reduce confounding and bias. The investigators of each outbreak reported likely time and cost savings from using market research controls. There were systematic differences between case and control groups in some studies but no evidence that conclusions on the likely source or vehicle of infection were incorrect. Potential selection biases introduced by using this sampling frame and the low response rate are unclear. Methods that might reduce confounding and some bias should be balanced with concerns for overmatching. Further evaluation of this approach using comparisons with traditional methods and population-based exposure survey data is recommended.

The iPod Revolution: An Exploratory Case Study of the Implementation of an iPod Touch Pilot Program

Science.gov (United States)

Stanfield, Staci A.

2013-01-01

This exploratory case study was designed to investigate the implementation of an iPod touch pilot program in sixth grade science classrooms at an intermediate school in Southeast Texas. More specifically, this study explored the benefits and challenges associated with the utilization of iPod touch devices for students, teachers, and their campus…

A Pilot Study Investigating the Effects of Advanced Nuclear Power Plant Control Room Technologies: Methods and Qualitative Results

Energy Technology Data Exchange (ETDEWEB)

BLanc, Katya Le [Idaho National Lab. (INL), Idaho Falls, ID (United States); Powers, David [Idaho National Lab. (INL), Idaho Falls, ID (United States); Joe, Jeffrey [Idaho National Lab. (INL), Idaho Falls, ID (United States); Spielman, Zachary [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rice, Brandon [Idaho National Lab. (INL), Idaho Falls, ID (United States); Fitzgerald, Kirk [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-08-01

Control room modernization is an important part of life extension for the existing light water reactor fleet. None of the 99 currently operating commercial nuclear power plants in the U.S. has completed a full-scale control room modernization to date. Nuclear power plant main control rooms for the existing commercial reactor fleet remain significantly analog, with only limited digital modernizations. Upgrades in the U.S. do not achieve the full potential of newer technologies that might otherwise enhance plant and operator performance. The goal of the control room upgrade benefits research is to identify previously overlooked benefits of modernization, identify candidate technologies that may facilitate such benefits, and demonstrate these technologies through human factors research. This report describes a pilot study to test upgrades to the Human Systems Simulation Laboratory at INL.

Experience with a three-axis side-located controller during a static and centrifuge simulation of the piloted launch of a manned multistage vehicle

Science.gov (United States)

Andrews, William H.; Holleman, Euclid C.

1960-01-01

An investigation was conducted to determine a human pilot's ability to control a multistage vehicle through the launch trajectory. The simulation was performed statically and dynamically by utilizing a human centrifuge. An interesting byproduct of the program was the three-axis side-located controller incorporated for pilot control inputs. This method of control proved to be acceptable for the successful completion of the tracking task during the simulation. There was no apparent effect of acceleration on the mechanical operation of the controller, but the pilot's control feel deteriorated as his dexterity decreased at high levels of acceleration. The application of control in a specific control mode was not difficult. However, coordination of more than one mode was difficult, and, in many instances, resulted in inadvertent control inputs. The acceptable control harmony at an acceleration level of 1 g became unacceptable at higher acceleration levels. Proper control-force harmony for a particular control task appears to be more critical for a three-axis controller than for conventional controllers. During simulations in which the pilot wore a pressure suit, the nature of the suit gloves further aggravated this condition.

Defining Feasibility and Pilot Studies in Preparation for Randomised Controlled Trials: Development of a Conceptual Framework.

Directory of Open Access Journals (Sweden)

Sandra M Eldridge

Full Text Available We describe a framework for defining pilot and feasibility studies focusing on studies conducted in preparation for a randomised controlled trial. To develop the framework, we undertook a Delphi survey; ran an open meeting at a trial methodology conference; conducted a review of definitions outside the health research context; consulted experts at an international consensus meeting; and reviewed 27 empirical pilot or feasibility studies. We initially adopted mutually exclusive definitions of pilot and feasibility studies. However, some Delphi survey respondents and the majority of open meeting attendees disagreed with the idea of mutually exclusive definitions. Their viewpoint was supported by definitions outside the health research context, the use of the terms 'pilot' and 'feasibility' in the literature, and participants at the international consensus meeting. In our framework, pilot studies are a subset of feasibility studies, rather than the two being mutually exclusive. A feasibility study asks whether something can be done, should we proceed with it, and if so, how. A pilot study asks the same questions but also has a specific design feature: in a pilot study a future study, or part of a future study, is conducted on a smaller scale. We suggest that to facilitate their identification, these studies should be clearly identified using the terms 'feasibility' or 'pilot' as appropriate. This should include feasibility studies that are largely qualitative; we found these difficult to identify in electronic searches because researchers rarely used the term 'feasibility' in the title or abstract of such studies. Investigators should also report appropriate objectives and methods related to feasibility; and give clear confirmation that their study is in preparation for a future randomised controlled trial designed to assess the effect of an intervention.

Defining Feasibility and Pilot Studies in Preparation for Randomised Controlled Trials: Development of a Conceptual Framework.

Science.gov (United States)

Eldridge, Sandra M; Lancaster, Gillian A; Campbell, Michael J; Thabane, Lehana; Hopewell, Sally; Coleman, Claire L; Bond, Christine M

2016-01-01

We describe a framework for defining pilot and feasibility studies focusing on studies conducted in preparation for a randomised controlled trial. To develop the framework, we undertook a Delphi survey; ran an open meeting at a trial methodology conference; conducted a review of definitions outside the health research context; consulted experts at an international consensus meeting; and reviewed 27 empirical pilot or feasibility studies. We initially adopted mutually exclusive definitions of pilot and feasibility studies. However, some Delphi survey respondents and the majority of open meeting attendees disagreed with the idea of mutually exclusive definitions. Their viewpoint was supported by definitions outside the health research context, the use of the terms 'pilot' and 'feasibility' in the literature, and participants at the international consensus meeting. In our framework, pilot studies are a subset of feasibility studies, rather than the two being mutually exclusive. A feasibility study asks whether something can be done, should we proceed with it, and if so, how. A pilot study asks the same questions but also has a specific design feature: in a pilot study a future study, or part of a future study, is conducted on a smaller scale. We suggest that to facilitate their identification, these studies should be clearly identified using the terms 'feasibility' or 'pilot' as appropriate. This should include feasibility studies that are largely qualitative; we found these difficult to identify in electronic searches because researchers rarely used the term 'feasibility' in the title or abstract of such studies. Investigators should also report appropriate objectives and methods related to feasibility; and give clear confirmation that their study is in preparation for a future randomised controlled trial designed to assess the effect of an intervention.

Pilot/Controller Coordinated Decision Making in the Next Generation Air Transportation System

Science.gov (United States)

Bearman, Chris; Miller, Ronald c.; Orasanu, Judith M.

2011-01-01

Introduction: NextGen technologies promise to provide considerable benefits in terms of enhancing operations and improving safety. However, there needs to be a thorough human factors evaluation of the way these systems will change the way in which pilot and controllers share information. The likely impact of these new technologies on pilot/controller coordinated decision making is considered in this paper using the "operational, informational and evaluative disconnect" framework. Method: Five participant focus groups were held. Participants were four experts in human factors, between x and x research students and a technical expert. The participant focus group evaluated five key NextGen technologies to identify issues that made different disconnects more or less likely. Results: Issues that were identified were: Decision Making will not necessarily improve because pilots and controllers possess the same information; Having a common information source does not mean pilots and controllers are looking at the same information; High levels of automation may lead to disconnects between the technology and pilots/controllers; Common information sources may become the definitive source for information; Overconfidence in the automation may lead to situations where appropriate breakdowns are not initiated. Discussion: The issues that were identified lead to recommendations that need to be considered in the development of NextGen technologies. The current state of development of these technologies provides a good opportunity to utilize recommendations at an early stage so that NextGen technologies do not lead to difficulties in resolving breakdowns in coordinated decision making.

Simulator Investigation of Pilot Aids for Helicopter Terminal Area Operations with One Engine Inoperative

Science.gov (United States)

Iseler, Laura; Chen, Robert; Dearing, Munro; Decker, William; Aiken, Edwin W. (Technical Monitor)

1995-01-01

Two recent piloted simulation experiments have investigated advanced display concepts applied to civil transport helicopter terminal area operations. Civil Category A helicopter operations apply to multi-engine helicopters wherein a safe recovery (land or fly out) is required in the event of a single engine failure. The investigation used the NASA Ames Research Center Vertical Motion Simulator, which has a full six degrees of freedom, to simulate the flight task as closely as possible. The goal of these experiments was to use advanced cockpit displays to improve flight safety and enhance the mission performance of Category A terminal area operations in confined areas. The first experiment investigated the use of military display formats to assist civil rotorcraft in performing a Category A takeoff in confined terminal areas. Specifically, it addressed how well a difficult hovering backup path could be followed using conventional instruments in comparison to panel mounted integrated displays. The hovering backup takeoff, which enables pilots to land back to the confined area pad in the event of an engine failure, was chosen since it is a difficult task to perform. Seven NASA and Army test pilots participated in the experiment. Evaluations, based on task performance and pilot workload, showed that an integrated display enabled the pilot to consistently achieve adequate or desired performance with reasonable pilot workload. Use of conventional instruments, however, frequently resulted in unacceptable performance (poor flight path tracking), higher pilot workload, and poor situational awareness. Although OEI landbacks were considered a visual task, the improved performance on the backup portion, in conjunction with increased situational awareness resulting from use of integrated displays, enabled the pilots to handle an engine failure and land back safely. In contrast, use of conventional instruments frequently led to excessive rates of sink at touchdown. A second

Linking the Pilot Structural Model and Pilot Workload

Science.gov (United States)

Bachelder, Edward; Hess, Ronald; Aponso, Bimal; Godfroy-Cooper, Martine

2018-01-01

Behavioral models are developed that closely reproduced pulsive control response of two pilots using markedly different control techniques while conducting a tracking task. An intriguing find was that the pilots appeared to: 1) produce a continuous, internally-generated stick signal that they integrated in time; 2) integrate the actual stick position; and 3) compare the two integrations to either issue or cease a pulse command. This suggests that the pilots utilized kinesthetic feedback in order to sense and integrate stick position, supporting the hypothesis that pilots can access and employ the proprioceptive inner feedback loop proposed by Hess's pilot Structural Model. A Pilot Cost Index was developed, whose elements include estimated workload, performance, and the degree to which the pilot employs kinesthetic feedback. Preliminary results suggest that a pilot's operating point (parameter values) may be based on control style and index minimization.

Effects of errorless skill learning in people with mild-to-moderate or severe dementia: a randomized controlled pilot study.

NARCIS (Netherlands)

Kessels, R.P.C.; Hensken, L.M.

2009-01-01

This pilot study examines whether learning without errors is advantageous compared to trial-and-error learning in people with dementia using a procedural task and a randomized case-control design. A sample of 60 people was recruited, consisting of 20 patients with severe dementia, 20 patients with

Effects of errorless skill learning in people with mild-to-moderate or severe dementia: A randomized controlled pilot study

NARCIS (Netherlands)

Kessels, R.P.C.; Olde Hensken, L.M.G.

2009-01-01

This pilot study examines whether learning without errors is advantageous compared to trial-and-error learning in people with dementia using a procedural task and a randomized case-control design. A sample of 60 people was recruited, consisting of 20 patients with severe dementia, 20 patients with

Postural control and shoulder steadiness in F-16 pilots

DEFF Research Database (Denmark)

Lange, Britt; Murray, Mike; Chreiteh, Shadi S

2014-01-01

to a control group (CG; N = 28) or training group (TG; N = 27). Postural control was tested in four different settings: Romberg with open and closed eyes, unilateral stance, and perturbation. Maximal voluntary contraction and force steadiness was measured for shoulder elevation. RESULTS: At follow......-up, there was a significant between-group difference in the Romberg test with closed eyes only (95% confidence ellipse area; CG: 761 +/- 311 mm2; TG: 650 +/- 405 mm2). Prior to randomization, there were no significant differences in postural control and steadiness between 30 pilots who experienced neck pain within...... the previous 3 mo and 25 pilots without such pain. DISCUSSION: Impaired postural control and steadiness may only be quantifiable in individuals experiencing acute neck pain of certain intensity, and there may be a ceiling effect in the ability to improve these parameters. For individuals with highly developed...

Implementation and flight-test of a multi-mode rotorcraft flight-control system for single-pilot use in poor visibility

Science.gov (United States)

Hindson, William S.

1987-01-01

A flight investigation was conducted to evaluate a multi-mode flight control system designed according to the most recent recommendations for handling qualities criteria for new military helicopters. The modes and capabilities that were included in the system are those considered necessary to permit divided-attention (single-pilot) lowspeed and hover operations near the ground in poor visibility conditions. Design features included mode-selection and mode-blending logic, the use of an automatic position-hold mode that employed precision measurements of aircraft position, and a hover display which permitted manually-controlled hover flight tasks in simulated instrument conditions. Pilot evaluations of the system were conducted using a multi-segment evaluation task. Pilot comments concerning the use of the system are provided, and flight-test data are presented to show system performance.

Process control of an HTGR fuel reprocessing cold pilot plant

International Nuclear Information System (INIS)

Rode, J.S.

1976-10-01

Development of engineering-scale systems for a large-scale HTGR fuel reprocessing demonstration facility is currently underway in a cold pilot plant. These systems include two fluidized-bed burners, which remove the graphite (carbon) matrix from the crushed HTGR fuel by high temperature (900 0 C) oxidation. The burners are controlled by a digital process controller with an all analog input/output interface which has been in use since March, 1976. The advantages of such a control system to a pilot plant operation can be summarized as follows: (1) Control loop functions and configurations can be changed easily; (2) control constants, alarm limits, output limits, and scaling constants can be changed easily; (3) calculation of data and/or interface with a computerized information retrieval system during operation are available; (4) diagnosis of process control problems is facilitated; and (5) control panel/room space is saved

Early Maladaptive Schemas in a Sample of Airline Pilots seeking Residential Substance Use Treatment: An Initial Investigation.

Science.gov (United States)

Shorey, Ryan C; Brasfield, Hope; Anderson, Scott; Stuart, Gregory L

2014-01-01

Recent research has begun to examine the early maladaptive schemas of substance abusers, as it is believed that targeting these core beliefs in treatment may result in improved substance use outcomes. One special population that has received scant attention in the research literature, despite high levels of substance use, is airline pilots. The current study examined the early maladaptive schemas of a sample of airline pilots ( n = 64) who were seeking residential treatment for alcohol dependence and whether they differed in early maladaptive schemas from non-pilot substance abusers who were also seeking residential treatment for alcohol dependence ( n = 45). Pre-existing medical records from patients of a residential substance abuse treatment facility were reviewed for the current study. Of the 18 early maladaptive schemas, results demonstrated that pilots scored higher than non-pilots on the early maladaptive schema of unrelenting standards (high internalized standards of behavior), whereas non-pilots scored higher on insufficient self-control (low frustration tolerance and self-control). Early maladaptive schemas may be a relevant treatment target for substance abuse treatment seeking pilots and non-pilots.

Comparison of proposed frameworks for grouping polychlorinated biphenyl congener data applied to a case-control pilot study of prostate cancer

International Nuclear Information System (INIS)

Ritchie, Justine M.; Vial, Scott L.; Fuortes, Laurence J.; Robertson, Larry W.; Guo, Haijun; Reedy, Victoria E.; Smith, Elaine M.

2005-01-01

Although the commercial synthesis of polychlorinated biphenyls (PCBs) has been banned in the United States for several decades, they are persistent in the environment with exposure mainly being through diet. The biologic and toxic effects of PCBs and their metabolites are due in part to their ability to interact with several cellular and nuclear receptors, thereby altering signaling pathways and gene transcription. These effects include endocrine modulation and disruption. Therefore, the natural history of cancer in tissues expressing these receptors may be modulated by PCB congeners, which are known to have estrogenic, antiestrogenic, and other hormonal effects. Several frameworks for grouping PCB congeners based on these interactions have been proposed. We conducted a hospital-based, case-control pilot study of 58 prostate cancer cases and 99 controls to evaluate the association between the proposed PCB groupings and the risk of prostate cancer. Serum samples were analyzed for a total of 30 PCBs. In multivariate analyses, the odds of prostate cancer among men with the highest concentrations of moderately chlorinated PCBs or PCBs with phenobarbital-like activities (constitutively active receptor (CAR) agonists) was over two times that among men with the lowest concentrations. Increasing trends in risk across the concentration levels were also observed. These results suggest that a higher burden of PCBs that are CAR agonists may be positively associated with an increased risk of prostate cancer and they encourage further research in this area

Evaluation of moral case deliberation at the Dutch Health Care Inspectorate: a pilot study.

Science.gov (United States)

Seekles, Wike; Widdershoven, Guy; Robben, Paul; van Dalfsen, Gonny; Molewijk, Bert

2016-05-21

Moral case deliberation (MCD) as a form of clinical ethics support is usually implemented in health care institutions and educational programs. While there is no previous research on the use of clinical ethics support on the level of health care regulation, employees of regulatory bodies are regularly confronted with moral challenges. This pilot study describes and evaluates the use of MCD at the Dutch Health Care Inspectorate (IGZ). The objective of this pilot study is to investigate: 1) the current way of dealing with moral issues at the IGZ; 2) experience with and evaluation of MCD as clinical ethics support, and 3) future preferences and (perceived) needs regarding clinical ethics support for dealing with moral questions at the IGZ. We performed an explorative pilot study. The research questions were assessed by means of: 1) interviews with MCD participants during four focus groups; and 2) interviews with six key stakeholders at the IGZ. De qualitative data is illustrated by data from questionnaires on MCD outcomes, perspective taking and MCD evaluation. Professionals do not always recognize moral issues. Employees report a need for regular and structured moral support in health care regulation. The MCD meetings are evaluated positively. The most important outcomes of MCD are feeling secure and learning from others. Additional support is needed to successfully implement MCD at the Inspectorate. We conclude that the respondents perceive moral case deliberation as a useful form of clinical ethics support for dealing with moral questions and issues in health care regulation.

Shuttle Primary Reaction Control Subsystem Thruster Fuel Valve Pilot Seal Extrusion: A Failure Correlation

Science.gov (United States)

Waller, Jess; Saulsberry, Regor L.

2003-01-01

Pilot operated valves (POVs) are used to control the flow of hypergolic propellants monomethylhydrazine (fuel) and nitrogen tetroxide (oxidizer) to the Shuttle orbiter Primary Reaction Control Subsystem (PRCS) thrusters. The POV incorporates a two-stage design: a solenoid-actuated pilot stage, which in turn controls a pressure-actuated main stage. Isolation of propellant supply from the thruster chamber is accomplished in part by a captive polytetrafluoroethylene (PTFE) pilot seal retained inside a Custom 455.1 stainless steel cavity. Extrusion of the pilot seal restricts the flow of fuel around the pilot poppet, thus impeding or preventing the main valve stage from opening. It can also prevent the main stage from staying open with adequate force margin, particularly if there is gas in the main stage actuation cavity. During thruster operation on-orbit, fuel valve pilot seal extrusion is commonly indicated by low or erratic chamber pressure or failure of the thruster to fire upon command (Fail-Off). During ground turnaround, pilot seal extrusion is commonly indicated by slow gaseous nitrogen (GN2) main valve opening times (greater than 38 ms) or slow water main valve opening response times (greater than 33 ms). Poppet lift tests and visual inspection can also detect pilot seal extrusion during ground servicing; however, direct metrology on the pilot seat assembly provides the most quantitative and accurate means of identifying extrusion. Minimizing PRCS fuel valve pilot seal extrusion has become an important issue in the effort to improve PRCS reliability and reduce associated life cycle costs.

Reward-related genes and personality traits in alcohol-dependent individuals: a pilot case control study.

Science.gov (United States)

Landgren, Sara; Berglund, Kristina; Jerlhag, Elisabet; Fahlke, Claudia; Balldin, Jan; Berggren, Ulf; Zetterberg, Henrik; Blennow, Kaj; Engel, Jörgen A

2011-01-01

Components of the brain reward system, i.e. the mesolimbic dopamine, laterodorsal cholinergic and ghrelin signaling systems, have been implicated in alcohol reward in preclinical studies. Genetic variants of these systems have previously been linked to alcohol dependence. Here, we genotyped 31 single nucleotide polymorphisms (SNPs): 1 SNP in the dopamine D₂ receptor (DRD2) gene, 20 SNPs in 5 different nicotinic acetylcholine receptor subunit (CHRN*) genes, and 10 SNPs in the genes encoding pro-ghrelin (GHRL) and its receptor (GHSR), in a pilot study of type 1 alcoholics (n = 84) and healthy controls (n = 32). These individuals were characterized using the Temperament and Character Inventory. None of the SNPs were associated with risk of alcohol dependence in this population. The GG genotype of SNP rs13261190 in the CHRNB3 was associated with increased novelty seeking, while SNPs of the ghrelin signaling system were associated with decreased self-directedness (AA of rs495225, GHSR) and alterations in self-transcendence (AA of both rs42451 and rs35680, GHRL). In conclusion, this pilot study suggests that reward-related genes are associated with altered personality scores in type 1 alcohol dependence, which warrants future studies of these associations in larger study samples. Copyright © 2011 S. Karger AG, Basel.

Case studies of energy efficiency financing in the original five pilot states, 1993-1996

Energy Technology Data Exchange (ETDEWEB)

Farhar, B C; Collins, N E; Walsh, R W

1997-05-01

The purpose of this report is to document progress in state-level programs in energy efficiency financing programs that are linked with home energy rating systems. Case studies are presented of programs in five states using a federal pilot program to amortize the costs of home energy improvements. The case studies present background information, describe the states` program, list preliminary evaluation data and findings, and discuss problems and solution encountered in the programs. A comparison of experiences in pilot states will be used to provide guidelines for program implementers, federal agencies, and Congress. 5 refs.

Evaluation of homoeopathic treatment in polycystic ovary syndrome: A single-blind, randomised, placebo-controlled pilot study

OpenAIRE

Chetna Deep Lamba; Praveen Oberai; Raj K Manchanda; Padmalaya Rath; P Hima Bindu; Maya Padmanabhan

2018-01-01

Background and Objectives: This study was conducted with the primary objective of evaluating efficacy of Homoeopathy in establishing the menstrual regularity with improvement in either ultrasonological findings or hirsutism/acne. The quality of life was also assessed using polycystic ovary syndrome questionnaire (PCOSQ). Materials and Methods: A single-blind, randomised, placebo-controlled pilot study was conducted from February 2014 to May 2015 at two research centres. The cases fulfilling t...

Pilot Certification, Age of Pilot, and Drug Use in Fatal Civil Aviation Accidents.

Science.gov (United States)

Akparibo, Issaka Y; Stolfi, Adrienne

2017-10-01

This study examined the association between mean age of pilot, pilot license, pilot medical certificate and drug use trends in pilots fatally injured in aircraft accidents. The prevalence of prescription drugs, OTC drugs, controlled drugs and drugs that may be potentially impairing was also examined. This study was a descriptive observational study in which the NTSB Aviation Accident Database was searched from the period beginning January 1, 2012 to December 31, 2014. During the study period a total of 706 accidents involving 711 fatalities were investigated by the NTSB. This study included 633 of these accidents, involving 646 fatalities. Of these pilots, 42.1% had drugs in their biological samples. The prevalence of prescription drugs, controlled drugs, OTC drugs, opioids, and potentially impairing drugs in the fatally injured pilot population over the study period was 28.9%, 15.0%, 20.1%, 5.1%, and 25.5%, respectively. Pilots with any drugs in their samples were significantly older than those without drugs. Medical certificate held was associated with drug use; pilots who held third class certificates had the highest prevalence at 54.1%. Pilot license was not associated with drug use. In 3.8% of the accidents, drugs were a contributing factor in the cause. Despite current FAA medical regulations, potentially impairing drugs are frequently found in biological samples of fatally injured pilots in the U.S. More education of airmen by aviation medical examiners is needed on the safety of drug use.Akparibo IY, Stolfi A. Pilot certification, age of pilot, and drug use in fatal civil aviation accidents. Aerosp Med Hum Perform. 2017; 88(10):931-936.

Autogenic-feedback training improves pilot performance during emergency flying conditions

Science.gov (United States)

Kellar, Michael A.; Folen, Raymond A.; Cowings, Patricia S.; Toscano, William B.; Hisert, Glen L.

1994-01-01

Studies have shown that autonomous mode behavior is one cause of aircraft fatalities due to pilot error. In such cases, the pilot is in a high state of psychological and physiological arousal and tends to focus on one problem, while ignoring more critical information. This study examined the effect of training in physiological self-recognition and regulation, as a means of improving crew cockpit performance. Seventeen pilots were assigned to the treatment and control groups matched for accumulated flight hours. The treatment group comprised three pilots of HC-130 Hercules aircraft and four HH-65 Dolphin helicopter pilots; the control group comprised three pilots of HC-130's and six Dolphin helicopter pilots. During an initial flight, physiological data were recorded for each crew member and individual crew performance was rated by an instructor pilot. Eight crewmembers were then taught to regulate their own physiological response levels using Autogenic-Feedback Training (AFT). The remaining subjects received no training. During a second flight, treatment subjects showed significant improvement in performance, while controls did not improve. The results indicate that AFT management of high states of physiological arousal may improve pilot performance during emergency flying conditions.

Integration of Predictive Display and Aircraft Flight Control System

Directory of Open Access Journals (Sweden)

Efremov A.V.

2017-01-01

Full Text Available The synthesis of predictive display information and direct lift control system are considered for the path control tracking tasks (in particular landing task. The both solutions are based on pilot-vehicle system analysis and requirements to provide the highest accuracy and lowest pilot workload. The investigation was carried out for cases with and without time delay in aircraft dynamics. The efficiency of the both ways for the flying qualities improvement and their integration is tested by ground based simulation.

Pilot visual acquisition of traffic : operational communications from air traffic control operational communication.

Science.gov (United States)

2001-05-01

Avionics devices designed to provide pilots with graphically displayed traffic information will enable pilots to acquire and verify the identity of any intruder aircraft within the general area, either before or in accordance with a controller-issued...

Effectiveness of case management in the prevention of COPD re-admissions: a pilot study.

Science.gov (United States)

van Eeden, Annelies E; van de Poll, Ingrid; van Vulpen, Gertrud; Roldaan, Tim; Wagenaar, Wies; Boland, Melinde R S; Wolterbeek, Ron; Chavannes, Niels H

2017-11-25

Chronic obstructive pulmonary disease (COPD) exacerbations are associated with high disease burden and costs, especially in the case of hospitalizations. The overall number of hospital admissions due to exacerbations of COPD has increased. It is remarkable that re-admissions account for a substantial part of these hospitalizations. This pilot study investigates the use of case management to reduce re-admissions due to COPD. COPD patients with more than one hospitalization per year due to an exacerbation were included. The participants (n = 10) were closely monitored and intensively coached for 20 weeks after hospitalization. The case manager provided care in a person-focused manner. The case manager informed and supported the patient, took action when relapse threatened, coordinated and connected primary and secondary care. Data of 12 months before and after start of the intervention were compared. Primary outcome was the difference in number of hospitalizations. Secondary outcomes were health-related quality of life (measured by the Clinical COPD Questionnaire, CCQ) and dyspnoea (measured by the MRC Dyspnoea Scale). The incidence rate of hospitalizations was found to be 2.25 times higher (95% confidence interval [CI] 1.3-3.9; P = 0.004) 12 months before compared with 12 months after the start of case management. COPD patients had a mean CCQ score of 3.3 (95% CI 2.8-3.8) before and 2.4 (95% CI 1.9-2.8) after 20 weeks of case management; a difference of 1.0 (95% CI 0.4-1.6; P = 0.001). The mean MRC scores showed no significant differences before (4.3; 95% CI 3.7-4.9) and after the case management period (3.9; 95% CI 3.2-4.6); a difference of 0.4 (95% CI - 0.1 to 0.9; P = 0.114). This pilot study shows that the number of COPD hospital re-admissions decreased significantly after the introduction of a case manager. Moreover, there was an improvement in patient-reported health-related quality of life.

A report on the piloting of a novel computer-based medical case simulation for teaching and formative assessment of diagnostic laboratory testing

Directory of Open Access Journals (Sweden)

Clarence D. Kreiter

2011-01-01

Full Text Available Objectives: Insufficient attention has been given to how information from computer-based clinical case simulations is presented, collected, and scored. Research is needed on how best to design such simulations to acquire valid performance assessment data that can act as useful feedback for educational applications. This report describes a study of a new simulation format with design features aimed at improving both its formative assessment feedback and educational function. Methods: Case simulation software (LabCAPS was developed to target a highly focused and well-defined measurement goal with a response format that allowed objective scoring. Data from an eight-case computer-based performance assessment administered in a pilot study to 13 second-year medical students was analyzed using classical test theory and generalizability analysis. In addition, a similar analysis was conducted on an administration in a less controlled setting, but to a much large sample (n=143, within a clinical course that utilized two random case subsets from a library of 18 cases. Results: Classical test theory case-level item analysis of the pilot assessment yielded an average case discrimination of 0.37, and all eight cases were positively discriminating (range=0.11–0.56. Classical test theory coefficient alpha and the decision study showed the eight-case performance assessment to have an observed reliability of σ=G=0.70. The decision study further demonstrated that a G=0.80 could be attained with approximately 3 h and 15 min of testing. The less-controlled educational application within a large medical class produced a somewhat lower reliability for eight cases (G=0.53. Students gave high ratings to the logic of the simulation interface, its educational value, and to the fidelity of the tasks. Conclusions: LabCAPS software shows the potential to provide formative assessment of medical students’ skill at diagnostic test ordering and to provide valid feedback to

Pilot Critical Incident Reports as a Means to Identify Human Factors of Remotely Piloted Aircraft

Science.gov (United States)

Hobbs, Alan; Cardoza, Colleen; Null, Cynthia

2016-01-01

It has been estimated that aviation accidents are typically preceded by numerous minor incidents arising from the same causal factors that ultimately produced the accident. Accident databases provide in-depth information on a relatively small number of occurrences, however incident databases have the potential to provide insights into the human factors of Remotely Piloted Aircraft System (RPAS) operations based on a larger volume of less-detailed reports. Currently, there is a lack of incident data dealing with the human factors of unmanned aircraft systems. An exploratory study is being conducted to examine the feasibility of collecting voluntary critical incident reports from RPAS pilots. Twenty-three experienced RPAS pilots volunteered to participate in focus groups in which they described critical incidents from their own experience. Participants were asked to recall (1) incidents that revealed a system flaw, or (2) highlighted a case where the human operator contributed to system resilience or mission success. Participants were asked to only report incidents that could be included in a public document. During each focus group session, a note taker produced a de-identified written record of the incident narratives. At the end of the session, participants reviewed each written incident report, and made edits and corrections as necessary. The incidents were later analyzed to identify contributing factors, with a focus on design issues that either hindered or assisted the pilot during the events. A total of 90 incidents were reported. Human factor issues included the impact of reduced sensory cues, traffic separation in the absence of an out-the-window view, control latencies, vigilance during monotonous and ultra-long endurance flights, control station design considerations, transfer of control between control stations, the management of lost link procedures, and decision-making during emergencies. Pilots participated willingly and enthusiastically in the study

Hearing loss in civilian airline and helicopter pilots compared to air traffic control personnel.

Science.gov (United States)

Wagstaff, Anthony S; Arva, Per

2009-10-01

In order to investigate possible hearing loss as a consequence of aviation noise, a comparative analysis of audiometric data from Norwegian Air Traffic Control (ATC) personnel, airline (fixed-wing) pilots, and helicopter pilots was performed. The results may be of use in giving advice regarding preventive measures. Male ATC, airline, and helicopter pilots were selected randomly from the Civil Aviation Authority (CAA) medical files. There were 182 subjects included in the study: 50, 81, and 51 subjects for ATC, helicopter, and airline pilots, respectively. Two audiograms with a 2-3-yr interval were analyzed for each individual. Age correction was performed using data from ISO 7129. Threshold changes per year for the frequencies 3, 4, and 6 kHz were examined in particular after age correction. For all three groups, mean hearing threshold levels were above (worse than) ISO 7129 predictions for most frequencies. As expected, hearing thresholds increased with age in the group as a whole. Looking at the 3-, 4-, and 6-kHz frequencies in particular, all groups had small but highly significant increases in hearing thresholds at 4 kHz between the first and second audiogram. The mean hearing thresholds for this group of aviation personnel are higher than International Standard ISO-7129 would predict according to age. Highly significant changes in hearing threshold after age correction, indicating possible noise-induced hearing loss, were found in all groups at 4 kHz. The fact that helicopter pilots had similar hearing loss to their other aviation colleagues indicates that current hearing protection for these pilots is effective in counteracting the increased noise levels in helicopters.

An investigation of breast cancer risk factors in Cyprus: a case control study

Directory of Open Access Journals (Sweden)

Hadjisavvas Andreas

2010-08-01

Full Text Available Abstract Background Breast cancer is the most common form of malignancy affecting women worldwide. It is also the leading cancer in females in Cyprus, with approximately 400 new cases diagnosed annually. It is well recognized that genetic variation as well as environmental factors modulate breast cancer risk. The main aim of this study was to assess the strength of associations between recognized risk factors and breast cancer among Cypriot women. This is the first epidemiological investigation on risk factors of breast cancer among the Cypriot female population. Methods We carried out a case-control study, involving 1,109 breast cancer patients and a group of 1,177 controls who were recruited while participating in the National screening programme for breast cancer. Information on demographic characteristics and potential risk factors were collected from both groups during a standardized interview. Logistic regression analysis was used to assess the strength of the association between each risk factor and breast cancer risk, before and after adjusting for the possible confounding effect of other factors. Results In multivariable models, family history of breast cancer (OR 1.64, 95% CI 1.23, 2.19 was the strongest predictor of breast cancer risk in the Cypriot population. Late menarche (OR 0.64, 95% CI 0.45, 0.92 among women reaching menarche after the age of 15 vs. before the age of 12 and breastfeeding (OR 0.74, 95% CI 0.59, 0.92 exhibited a strong protective effect. In the case of breastfeeding, the observed effect appeared stronger than the effect of pregnancy alone. Surprisingly, we also observed an inverse association between hormone replacement therapy (HRT although this may be a product of the retrospective nature of this study. Conclusion Overall the findings of our study corroborate with the results of previous investigations on descriptive epidemiology of risk factors for breast cancer. This investigation provides important background

Feasibility and preliminary effectiveness of ice therapy in patients with an acute tear in the gastrocnemius muscle: A pilot randomized controlled trial

NARCIS (Netherlands)

Prins, J.C.M.; Stubbe, J.H.; Meeteren, N.L.U. van; Scheffers, F.A.; Dongen, M.C.J.M. van

2011-01-01

Objective: To investigate the feasibility of a randomized controlled trial and the preliminary effectiveness of ice therapy in the acute phase of a gastrocnemius tear for the quality of functional recovery. Design: A pilot version of an intended prospective randomized controlled clinical trial was

Adaptive control of anaerobic digestion processes-a pilot-scale application.

Science.gov (United States)

Renard, P; Dochain, D; Bastin, G; Naveau, H; Nyns, E J

1988-03-01

A simple adaptive control algorithm, for which theoretical stability and convergence properties had been previously demonstrated, has been successfully implemented on a biomethanation pilot reactor. The methane digester, operated in the CSTR mode was submitted to a shock load, and successfully computer controlled during the subsequent transitory state.

A pilot investigation to optimise methods for a future satiety preload study

OpenAIRE

Hobden, Mark R.; Guérin-Deremaux, Laetitia; Commane, Daniel M.; Rowland, Ian; Gibson, Glenn R.; Kennedy, Orla B.

2017-01-01

Background Preload studies are used to investigate the satiating effects of foods and food ingredients. However, the design of preload studies is complex, with many methodological considerations influencing appetite responses. The aim of this pilot investigation was to determine acceptability, and optimise methods, for a future satiety preload study. Specifically, we investigated the effects of altering (i) energy intake at a standardised breakfast (gender-specific or non-gender specific), an...

An experimental study of the effect of a pilot flame on technically pre-mixed, self-excited combustion instabilities

Science.gov (United States)

O'Meara, Bridget C.

Combustion instabilities are a problem facing the gas turbine industry in the operation of lean, pre-mixed combustors. Secondary flames known as "pilot flames" are a common passive control strategy for eliminating combustion instabilities in industrial gas turbines, but the underlying mechanisms responsible for the pilot flame's stabilizing effect are not well understood. This dissertation presents an experimental study of a pilot flame in a single-nozzle, swirl-stabilized, variable length atmospheric combustion test facility and the effect of the pilot on combustion instabilities. A variable length combustor tuned the acoustics of the system to excite instabilities over a range of operating conditions without a pilot flame. The inlet velocity was varied from 25 -- 50 m/s and the equivalence ratio was varied from 0.525 -- 0.65. This range of operating conditions was determined by the operating range of the combustion test facility. Stability at each operating condition and combustor length was characterized by measurements of pressure oscillations in the combustor. The effect of the pilot flame on the magnitude and frequency of combustor stability was then investigated. The mechanisms responsible for the pilot flame effect were studied using chemiluminescence flame images of both stable and unstable flames. Stable flame structure was investigated using stable flame images of CH* chemiluminescence emission. The effect of the pilot on stable flame metrics such as flame length, flame angle, and flame width was investigated. In addition, a new flame metric, flame base distance, was defined to characterize the effect of the pilot flame on stable flame anchoring of the flame base to the centerbody. The effect of the pilot flame on flame base anchoring was investigated because the improved stability with a pilot flame is usually attributed to improved flame anchoring through the recirculation of hot products from the pilot to the main flame base. Chemiluminescence images

Methodology Series Module 2: Case-control Studies.

Science.gov (United States)

Setia, Maninder Singh

2016-01-01

Case-Control study design is a type of observational study. In this design, participants are selected for the study based on their outcome status. Thus, some participants have the outcome of interest (referred to as cases), whereas others do not have the outcome of interest (referred to as controls). The investigator then assesses the exposure in both these groups. The investigator should define the cases as specifically as possible. Sometimes, definition of a disease may be based on multiple criteria; thus, all these points should be explicitly stated in case definition. An important aspect of selecting a control is that they should be from the same 'study base' as that of the cases. We can select controls from a variety of groups. Some of them are: General population; relatives or friends; and hospital patients. Matching is often used in case-control control studies to ensure that the cases and controls are similar in certain characteristics, and it is a useful technique to increase the efficiency of the study. Case-Control studies can usually be conducted relatively faster and are inexpensive - particularly when compared with cohort studies (prospective). It is useful to study rare outcomes and outcomes with long latent periods. This design is not very useful to study rare exposures. Furthermore, they may also be prone to certain biases - selection bias and recall bias.

Efficient Conversation: The Talk between Pilots and Air Traffic Controllers.

Science.gov (United States)

Simmons, James L.

Two-way radio communications between air traffic controllers using radar on the ground to give airplane pilots instructions are of interest within the developing framework of the sociology of language. The main purpose of air traffic control language is efficient communication to promote flight safety. This study describes the standardized format…

On the pilot's behavior of detecting a system parameter change

Science.gov (United States)

Morizumi, N.; Kimura, H.

1986-01-01

The reaction of a human pilot, engaged in compensatory control, to a sudden change in the controlled element's characteristics is described. Taking the case where the change manifests itself as a variance change of the monitored signal, it is shown that the detection time, defined to be the time elapsed until the pilot detects the change, is related to the monitored signal and its derivative. Then, the detection behavior is modeled by an optimal controller, an optimal estimator, and a variance-ratio test mechanism that is performed for the monitored signal and its derivative. Results of a digital simulation show that the pilot's detection behavior can be well represented by the model proposed here.

Using Statistical Process Control Methods to Classify Pilot Mental Workloads

National Research Council Canada - National Science Library

Kudo, Terence

2001-01-01

.... These include cardiac, ocular, respiratory, and brain activity measures. The focus of this effort is to apply statistical process control methodology on different psychophysiological features in an attempt to classify pilot mental workload...

Simulation of Controller Pilot Data Link Communications over VHF Digital Link Mode 3

Science.gov (United States)

Bretmersky, Steven C.; Murawski, Robert; Nguyen, Thanh C.; Raghavan, Rajesh S.

2004-01-01

The Federal Aviation Administration (FAA) has established an operational plan for the future Air Traffic Management (ATM) system, in which the Controller Pilot Data Link Communications (CPDLC) is envisioned to evolve into digital messaging that will take on an ever increasing role in controller to pilot communications, significantly changing the way the National Airspace System (NAS) is operating. According to FAA, CPDLC represents the first phase of the transition from the current analog voice system to an International Civil Aviation Organization (ICAO) compliant system in which digital communication becomes the alternate and perhaps primary method of routine communication. The CPDLC application is an Air Traffic Service (ATS) application in which pilots and controllers exchange messages via an addressed data link. CPDLC includes a set of clearance, information, and request message elements that correspond to existing phraseology employed by current Air Traffic Control (ATC) procedures. These message elements encompass altitude assignments, crossing constraints, lateral deviations, route changes and clearances, speed assignments, radio frequency assignments, and various requests for information. The pilot is provided with the capability to respond to messages, to request clearances and information, to report information, and to declare/rescind an emergency. A 'free text' capability is also provided to exchange information not conforming to defined formats. This paper presents simulated results of the aeronautical telecommunication application Controller Pilot Data Link Communications over VHF Digital Link Mode 3 (VDL Mode 3). The objective of this simulation study was to determine the impact of CPDLC traffic loads, in terms of timely message delivery and capacity of the VDL Mode 3 subnetwork. The traffic model is based on and is used for generating air/ground messages with different priorities. Communication is modeled for the en route domain of the Cleveland

Influence of Cultural, Organizational, and Automation Capability on Human Automation Trust: A Case Study of Auto-GCAS Experimental Test Pilots

Science.gov (United States)

Koltai, Kolina; Ho, Nhut; Masequesmay, Gina; Niedober, David; Skoog, Mark; Cacanindin, Artemio; Johnson, Walter; Lyons, Joseph

2014-01-01

This paper discusses a case study that examined the influence of cultural, organizational and automation capability upon human trust in, and reliance on, automation. In particular, this paper focuses on the design and application of an extended case study methodology, and on the foundational lessons revealed by it. Experimental test pilots involved in the research and development of the US Air Force's newly developed Automatic Ground Collision Avoidance System served as the context for this examination. An eclectic, multi-pronged approach was designed to conduct this case study, and proved effective in addressing the challenges associated with the case's politically sensitive and military environment. Key results indicate that the system design was in alignment with pilot culture and organizational mission, indicating the potential for appropriate trust development in operational pilots. These include the low-vulnerability/ high risk nature of the pilot profession, automation transparency and suspicion, system reputation, and the setup of and communications among organizations involved in the system development.

Occupational Stress and Hypertension among Railway Loco Pilots and Section Controllers

OpenAIRE

Jayakumar, Devasigamoney

2017-01-01

Introduction: A cross-sectional study on occupational stress was conducted on loco pilots in 2008, in view of loco pilots being one of the high strain jobs in Indian Railways. Subsequently, a comparative cross-sectional study on occupational stress was conducted among section controllers in 2011, which is another high strain job of Indian Railways. Objective: The studies were conducted to analyze and compare occupational stress and hypertension. Setting and Design: A cross-sectional study on ...

Synthetic perspective optical flow: Influence on pilot control tasks

Science.gov (United States)

Bennett, C. Thomas; Johnson, Walter W.; Perrone, John A.; Phatak, Anil V.

1989-01-01

One approach used to better understand the impact of visual flow on control tasks has been to use synthetic perspective flow patterns. Such patterns are the result of apparent motion across a grid or random dot display. Unfortunately, the optical flow so generated is based on a subset of the flow information that exists in the real world. The danger is that the resulting optical motions may not generate the visual flow patterns useful for actual flight control. Researchers conducted a series of studies directed at understanding the characteristics of synthetic perspective flow that support various pilot tasks. In the first of these, they examined the control of altitude over various perspective grid textures (Johnson et al., 1987). Another set of studies was directed at studying the head tracking of targets moving in a 3-D coordinate system. These studies, parametric in nature, utilized both impoverished and complex virtual worlds represented by simple perspective grids at one extreme, and computer-generated terrain at the other. These studies are part of an applied visual research program directed at understanding the design principles required for the development of instruments displaying spatial orientation information. The experiments also highlight the need for modeling the impact of spatial displays on pilot control tasks.

Postural control and shoulder steadiness in F-16 pilots

DEFF Research Database (Denmark)

Lange, Britt; Murray, Mike; Chreiteh, Shadi S

2014-01-01

BACKGROUND: During maneuvering, fighter pilots experience loads of up to 50-70 kg on their necks. Neck disorders are common and have been linked to impairment in muscle control. We conducted an intervention study introducing targeted training for 24 wk that reduced neck pain. The current study re...

Risk and protective factors for spasmodic dysphonia: a case-control investigation.

Science.gov (United States)

Tanner, Kristine; Roy, Nelson; Merrill, Ray M; Kimber, Kamille; Sauder, Cara; Houtz, Daniel R; Doman, Darrin; Smith, Marshall E

2011-01-01

Spasmodic dysphonia (SD) is a chronic, incurable, and often disabling voice disorder of unknown pathogenesis. The purpose of this study was to identify possible endogenous and exogenous risk and protective factors uniquely associated with SD. Prospective, exploratory, case-control investigation. One hundred fifty patients with SD and 150 medical controls (MCs) were interviewed regarding their personal and family histories, environmental exposures, illnesses, injuries, voice use patterns, and general health using a previously vetted and validated epidemiologic questionnaire. Odds ratios and multiple logistic regression analyses (α<0.15) identified several factors that significantly increased the likelihood of having SD. These factors included (1) a personal history of mumps, blepharospasm, tremor, intense occupational and avocational voice use, and a family history of voice disorders; (2) an immediate family history of meningitis, tremor, tics, cancer, and compulsive behaviors; and (3) an extended family history of tremor and cancer. SD is likely multifactorial in etiology, involving both genetic and environmental factors. Viral infections/exposures, along with intense voice use, may trigger the onset of SD in genetically predisposed individuals. Future studies should examine the interaction among genetic and environmental factors to determine the pathogenesis of SD. Copyright © 2011 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Simulating extreme environments: Ergonomic evaluation of Chinese pilot performance and heat stress tolerance.

Science.gov (United States)

Li, Jing; Tian, Yinsheng; Ding, Li; Zou, Huijuan; Ren, Zhaosheng; Shi, Liyong; Feathers, David; Wang, Ning

2015-06-05

High-temperatures in the cockpit environment can adversely influence pilot behavior and performance. To investigate the impact of high thermal environments on Chinese pilot performance in a simulated cockpit environment. Ten subjects volunteered to participate in the tests under 40°C and 45°C high-temperature simulations in an environmentally controlled chamber. Measures such as grip strength, perception, dexterity, somatic sense reaction, and analytical reasoning were taken. The results were compared to the Combined Index of Heat Stress (CIHS). CIHS exceeded the heat stress safety limit after 45 min under 40°C, grip strength decreased by 12% and somatic perception became 2.89 times larger than the initial value. In the case of 45°C, CIHS exceeded the safety limit after only 20 min, while the grip strength decreased just by 3.2% and somatic perception increased to 4.36 times larger than the initial value. Reaction and finger dexterity were not statistically different from baseline measurements, but the error rate of analytical reasoning test rose remarkably. Somatic perception was the most sensitive index to high-temperature, followed by grip strength. Results of this paper may help to improve environmental control design of new fighter cockpit and for pilot physiology and cockpit environment ergonomics research for Chinese pilots.

Effects of sleep bruxism on functional and occlusal parameters: a prospective controlled investigation

Science.gov (United States)

Alicia Ommerborn, Michelle; Giraki, Maria; Schneider, Christine; Michael Fuck, Lars; Handschel, Jörg; Franz, Matthias; Hans-Michael Raab, Wolfgang; Schäfer, Ralf

2012-01-01

This study was conducted to verify the results of a preceding retrospective pilot study by means of a prospective controlled investigation including a larger sample size. Therefore, the aim of this clinical investigation was to analyze the relationship between sleep bruxism and several functional and occlusal parameters. The null hypothesis of this study was that there would be no differences among sleep bruxism subjects and non-sleep bruxism controls regarding several functional and occlusal parameters. Fifty-eight sleep bruxism subjects and 31 controls participated in this study. The diagnosis sleep bruxism was based on clinical criteria of the American Academy of Sleep Medicine. Sixteen functional and occlusal parameters were recorded clinically or from dental study casts. Similar to the recently published retrospective pilot study, with a mean slide of 0.77 mm (s.d., 0.69 mm) in the sleep bruxism group and a mean slide of 0.4 mm (s.d., 0.57 mm) in the control group, the evaluation of the mean comparison between the two groups demonstrated a larger slide from centric occlusion to maximum intercuspation in sleep bruxism subjects (Mann–Whitney U-test; P=0.008). However, following Bonferroni adjustment, none of the 16 occlusal and functional variables differed significantly between the sleep bruxism subjects and the non-sleep bruxism controls. The present study shows that the occlusal and functional parameters evaluated do not differ between sleep bruxism subjects and non-sleep bruxism subjects. However, as the literature reveals a possible association between bruxism and certain subgroups of temporomandibular disorders, it appears advisable to incorporate the individual adaptive capacity of the stomatognathic system into future investigations. PMID:22935746

Effects of sleep bruxism on functional and occlusal parameters: a prospective controlled investigation.

Science.gov (United States)

Ommerborn, Michelle Alicia; Giraki, Maria; Schneider, Christine; Fuck, Lars Michael; Handschel, Jörg; Franz, Matthias; Hans-Michael Raab, Wolfgang; Schäfer, Ralf

2012-09-01

This study was conducted to verify the results of a preceding retrospective pilot study by means of a prospective controlled investigation including a larger sample size. Therefore, the aim of this clinical investigation was to analyze the relationship between sleep bruxism and several functional and occlusal parameters. The null hypothesis of this study was that there would be no differences among sleep bruxism subjects and non-sleep bruxism controls regarding several functional and occlusal parameters. Fifty-eight sleep bruxism subjects and 31 controls participated in this study. The diagnosis sleep bruxism was based on clinical criteria of the American Academy of Sleep Medicine. Sixteen functional and occlusal parameters were recorded clinically or from dental study casts. Similar to the recently published retrospective pilot study, with a mean slide of 0.77 mm (s.d., 0.69 mm) in the sleep bruxism group and a mean slide of 0.4 mm (s.d., 0.57 mm) in the control group, the evaluation of the mean comparison between the two groups demonstrated a larger slide from centric occlusion to maximum intercuspation in sleep bruxism subjects (Mann-Whitney U-test; P=0.008). However, following Bonferroni adjustment, none of the 16 occlusal and functional variables differed significantly between the sleep bruxism subjects and the non-sleep bruxism controls. The present study shows that the occlusal and functional parameters evaluated do not differ between sleep bruxism subjects and non-sleep bruxism subjects. However, as the literature reveals a possible association between bruxism and certain subgroups of temporomandibular disorders, it appears advisable to incorporate the individual adaptive capacity of the stomatognathic system into future investigations.

Horonobe Underground Research Laboratory project overview of the pilot borehole investigation of the ventilation shaft (PB-V01). Hydrogeological investigation

International Nuclear Information System (INIS)

Yabuuchi, Satoshi; Kunimaru, Takanori; Ishii, Eiichi; Hatsuyama, Yoshihiro; Ijiri, Yuji; Matsuoka, Kiyoyuki; Ibara, Tetsuo; Matsunami, Shinjiro; Makino, Akiya

2009-02-01

The Pilot Borehole Investigation of the Ventilation Shaft was conducted in Horonobe, Hokkaido, Japan from October 2007 to March 2008. Main purpose of the investigation is to understand geological, hydrogeological and hydrochemical properties of the formation where the Ventilation Shaft has been excavated. Hydraulic packer tests show that hydraulic conductivity lies in the range from 1.1E-11 to 1.4E-7 m/sec down to 500m in depth. This heterogeneity mainly depends on the distribution and permeability of groundwater inflow points, which were detected by Fluid Electric Conductivity logging. High conductive zones were found between 263m and 290m, 355m and 370m of the depth in the pilot borehole. An effective method for reducing groundwater inflow should be considered for the deeper Ventilation Shaft excavation. (author)

An Experimental Study of the Effect of Shared Information on Pilot/Controller Re-Route Negotiation

Science.gov (United States)

Farley, Todd C.; Hansman, R. John

1999-01-01

Air-ground data link systems are being developed to enable pilots and air traffic controllers to share information more fully. The sharing of information is generally expected to enhance their shared situation awareness and foster more collaborative decision making. An exploratory, part-task simulator experiment is described which evaluates the extent to which shared information may lead pilots and controllers to cooperate or compete when negotiating route amendments. The results indicate an improvement in situation awareness for pilots and controllers and a willingness to work cooperatively. Independent of data link considerations, the experiment also demonstrates the value of providing controllers with a good-quality weather representation on their plan view displays. Observed improvements in situation awareness and separation assurance are discussed. It is argued that deployment of this relatively simple, low-risk addition to the plan view displays be accelerated.

The effects of display and autopilot functions on pilot workload for Single Pilot Instrument Flight Rule (SPIFR) operations

Science.gov (United States)

Hoh, Roger H.; Smith, James C.; Hinton, David A.

1987-01-01

An analytical and experimental research program was conducted to develop criteria for pilot interaction with advanced controls and displays in single pilot instrument flight rules (SPIFR) operations. The analytic phase reviewed fundamental considerations for pilot workload taking into account existing data, and using that data to develop a divided attention SPIFR pilot workload model. The pilot model was utilized to interpret the two experimental phases. The first experimental phase was a flight test program that evaluated pilot workload in the presence of current and near-term displays and autopilot functions. The second experiment was conducted on a King Air simulator, investigating the effects of co-pilot functions in the presence of very high SPIFR workload. The results indicate that the simplest displays tested were marginal for SPIFR operations. A moving map display aided the most in mental orientation, but had inherent deficiencies as a stand alone replacement for an HSI. Autopilot functions were highly effective for reducing pilot workload. The simulator tests showed that extremely high workload situations can be adequately handled when co-pilot functions are provided.

The computer system for registration and dosimetric control of inhabitants, cosmonauts and pilots from the different radiation sources

International Nuclear Information System (INIS)

Lebedev, L.A.; Koniaev, S.V.; Mikheenko, S.G.; Rusin, S.V.; Sidorin, V.P.

1996-01-01

Cosmonauts, pilots and inhabitants living near the nuclear power plants or nuclear facilities are particular group of risk. To estimate the radiation risk for this limited part of population the Computer System was developed. The main purpose of this System is registration, account, storage, processing, analysis, forecasting and control both doses and radiation risks for each person. Both experimental and calculated data are used in the Computer System. The experimental data are used in case of estimation of doses received by cosmonauts during space flight and by pilots during the flight in atmosphere. The System allows to calculate the doses for each person from any type of medical procedures including the X-ray diagnostic examinations and radioisotopic diagnostics. The Computer System also allows to calculate the radiation exposure of inhabitants living near nuclear facilities both in case of normal exploitation and different kind of accidents. The annual dose distribution from different types of radiation sources are given. It was shown that doses from medical irradiation are comparable or sometime higher than the doses from space flight, air flight or nuclear accident. (author)

Step 1: Human System Integration (HSI) FY05 Pilot-Technology Interface Requirements for Command, Control, and Communications (C3)

Science.gov (United States)

2005-01-01

The document provides the Human System Integration(HSI) high-level functional C3 HSI requirements for the interface to the pilot. Description includes (1) the information required by the pilot to have knowledge C3 system status, and (2) the control capability needed by the pilot to obtain C3 information. Fundamentally, these requirements provide the candidate C3 technology concepts with the necessary human-related elements to make them compatible with human capabilities and limitations. The results of the analysis describe how C3 operations and functions should interface with the pilot to provide the necessary C3 functionality to the UA-pilot system. Requirements and guidelines for C3 are partitioned into three categories: (1) Pilot-Air Traffic Control (ATC) Voice Communications (2) Pilot-ATC Data Communications, and (3) command and control of the unmanned aircraft (UA). Each requirement is stated and is supported with a rationale and associated reference(s).

Radon and Lung Cancer Case-Control Study in Middle Ural

International Nuclear Information System (INIS)

Kirdin, I.A.; Lezhnin, V.L.; Yarmoshenko, I.V.; Ekidin, A.

2001-01-01

Full text: The pilot phase of radon and lung cancer case-control study has been performed in Karpinsk and Pervouralsk towns of Middle Ural region of Russia. The case group consists of 341 persons with lung cancer and living in that towns at least five previous years. The lung cancer diagnoses were carefully verified by instrumental techniques and 70% of its were morphologically validated. The persons for the control group (448) were chosen from the population living in that towns at least five years taking into account the age and sex. The special epidemiological questionnaire was developed which includes the items by the groups of factors as follow: clinical data, social factors, chronic lung diseases, life habit, tobacco smoking, alcohol drinking, diet preference etc. The epidemiological questionnaires were fulfilled for each member of case and control groups. Radon gas concentration and thoron equilibrium equivalent concentration measurements had been performed using nuclear track detectors and grab sampling accordingly in the dwellings of case and control groups members. By preliminary estimation the odds ratios are 1, 0.91, 1.2, 1.1 in the ranges of radon and thoron equilibrium equivalent concentration 0-6, 3-13, 13-36 and 36-370 Bq/m 3 respectively. The deeper and more rigorous analysis as well as different independent approaches will be discussed in the paper.(author)

Improving tuberculosis case detection in underdeveloped multi-ethnic regions with high disease burden: a case study of integrated control program in China.

Science.gov (United States)

Li, Jun; Liu, Xiao-Qiu; Jiang, Shi-Wen; Li, Xue; Yu, Fei; Wang, Yan; Peng, Yong; Gu, Xiao-Ming; Sun, Yan-Ni; Zhang, Hui; Wang, Li-Xia

2017-11-29

In the underdeveloped multi-ethnic regions of China, high tuberculosis (TB) burden and regional inequity in access to healthcare service increase the challenge of achieving the End TB goals. Among all the provinces, the highest TB burden is reported in Xinjiang, where ethnic minorities and older people have suffered most. However, current case-finding strategy is inadequate given the complex social determinants and suboptimal case detection rates. Thus, we developed an integrated TB control program to improve case detection and conducted a pilot in Xinjiang from 2014 to 2015. In this case study, we summarized the activities and key findings. We also shared the experiences and challenges of implementing interventions and provided recommendations to inform the TB control program in the future. The pilot interventions were implemented in one selected town in Yining based on local TB control programs. By applying tailor-made educational materials, outreach TB educational activities were conducted in diverse ways. In 22 Masjids, the trained imams promoted TB education to the Muslims, covering 20,440 person-times in 88 delivered preaching sessions. In seven schools, 1944 students were educated by the teachers and contributed to educating 6929 family members. In the village communities, 13,073 residents participated in household education and screening. Among them, 12,292 people aged under 65 years were investigated for suspicious pulmonary TB symptoms, where six TB patients were diagnosed out of 89 TB suspects; 781 older people were mobilized for screening directly by chest X-ray, where 10 patients were diagnosed out of 692 participants. Supportive healthcare system, multi-sectoral cooperation and multi-channel financing mechanism were the successful experiences of implementation. The interventions were proved to be more effective than the previous performance: the number of TB suspects consulting doctors and patients detected increased by 50% and 26%, respectively

Running injuries in novice runners enrolled in different training interventions: a pilot randomized controlled trial.

Science.gov (United States)

Baltich, J; Emery, C A; Whittaker, J L; Nigg, B M

2017-11-01

The purpose of this trial was to evaluate injury risk in novice runners participating in different strength training interventions. This was a pilot randomized controlled trial. Novice runners (n = 129, 18-60 years old, running experience) were block randomized to one of three groups: a "resistance" strength training group, a "functional" strength training group, or a stretching "control" group. The primary outcome was running related injury. The number of participants with complaints and the injury rate (IR = no. injuries/1000 running hours) were quantified for each intervention group. For the first 8 weeks, participants were instructed to complete their training intervention three to five times a week. The remaining 4 months was a maintenance period. NCT01900262. A total of 52 of the 129 (40%) novice runners experienced at least one running related injury: 21 in the functional strength training program, 16 in the resistance strength training program and 15 in the control stretching program. Injury rates did not differ between study groups [IR = 32.9 (95% CI 20.8, 49.3) in the functional group, IR = 31.6 (95% CI 18.4, 50.5) in the resistance group, and IR = 26.7 (95% CI 15.2, 43.2)] in the control group. Although this was a pilot assessment, home-based strength training did not appear to alter injury rates compared to stretching. Future studies should consider methods to minimize participant drop out to allow for the assessment of injury risk. Injury risk in novice runners based on this pilot study will inform the development of future larger studies investigating the impact of injury prevention interventions. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The oral microbiota in patients with pancreatic cancer, patients with IPMNs, and controls: a pilot study.

Science.gov (United States)

Olson, Sara H; Satagopan, Jaya; Xu, Youming; Ling, Lilan; Leong, Siok; Orlow, Irene; Saldia, Amethyst; Li, Peter; Nunes, Pamela; Madonia, Vincent; Allen, Peter J; O'Reilly, Eileen; Pamer, Eric; Kurtz, Robert C

2017-09-01

Poor oral health appears to be a risk factor for pancreatic cancer, possibly implicating the oral microbiota. In this pilot study, we evaluated the characteristics of the oral microbiota in patients with pancreatic ductal adenocarcinoma (PDAC), intraductal papillary mucinous neoplasms (IPMN), and healthy controls. Forty newly diagnosed PDAC patients, 39 IPMN patients, and 58 controls, excluding current smokers and users of antibiotics, provided saliva samples. Common oral bacterial species were comprehensively surveyed by sequencing of the 16S rRNA microbial genes. We obtained measures of diversity and the mean relative proportions of individual taxa. We explored the degree to which these measures differed according to respondent characteristics based on individual interviews. PDAC cases did not differ in diversity measures from either controls or IPMN cases. PDAC cases had higher mean relative proportions of Firmicutes and related taxa, while controls had higher mean relative proportions of Proteobacteria and related taxa. Results were generally similar when comparing PDAC to IPMN cases. Among IPMNs and controls combined, younger individuals had higher levels of several taxa within the Proteobacteria. The only other variable consistently related to mean relative proportions was mouthwash use, with taxa within Firmicutes more common among users. While there were no differences in diversity of the oral microbiota among these groups, there were differences in the mean relative proportions of some taxa. Characteristics of the oral microbiota are not associated with most measures of oral health.

Effects of False Tilt Cues on the Training of Manual Roll Control Skills

Science.gov (United States)

Zaal, Peter M. T.; Popovici, Alexandru; Zavala, Melinda A.

2015-01-01

This paper describes a transfer-of-training study performed in the NASA Ames Vertica lMotion Simulator. The purpose of the study was to investigate the effect of false tilt cues on training and transfer of training of manual roll control skills. Of specific interest were the skills needed to control unstable roll dynamics of a mid-size transport aircraft close to the stall point. Nineteen general aviation pilots trained on a roll control task with one of three motion conditions: no motion, roll motion only, or reduced coordinated roll motion. All pilots transferred to full coordinated roll motion in the transfer session. A novel multimodal pilot model identification technique was successfully applied to characterize how pilots' use of visual and motion cues changed over the course of training and after transfer. Pilots who trained with uncoordinated roll motion had significantly higher performance during training and after transfer, even though they experienced the false tilt cues. Furthermore, pilot control behavior significantly changed during the two sessions, as indicated by increasing visual and motion gains, and decreasing lead time constants. Pilots training without motion showed higher learning rates after transfer to the full coordinated roll motion case.

The effectiveness of origami on overall hand function after injury: A pilot controlled trial

OpenAIRE

Wilson, L; Roden, P; Taylor, Y; Marston, L

2008-01-01

This pilot study measured the effectiveness of using origami to improve the overall hand function of outpatients attending an NHS hand injury unit. The initiative came from one of the authors who had used origami informally in the clinical setting and observed beneficial effects. These observed effects were tested experimentally. The design was a pilot non-randomised controlled trial with 13 participants. Allocation of the seven control group members was based on patient preference. The exper...

Computational Analysis of Pharyngeal Swallowing Mechanics in Patients with Motor Neuron Disease: A Pilot Investigation.

Science.gov (United States)

Garand, K L; Schwertner, Ryan; Chen, Amy; Pearson, William G

2018-04-01

Swallowing impairment (dysphagia) is a common sequela in patients with motor neuron disease (MND). The purpose of this retrospective, observational pilot investigation was to characterize how pharyngeal swallowing mechanics are impacted in patients with MND using a comparison with healthy, non-dysphagic control group. Computational analysis of swallowing mechanics (CASM) was used to determine covariate biomechanics of pharyngeal swallowing from videofluoroscopic assessment in 15 patients with MND and 15 age- and sex-matched healthy controls. Canonical variant analysis with post hoc discriminate function analysis (DFA) was performed on coordinate data mapping functional muscle groups underlying pharyngeal swallowing. Differences in swallowing mechanics associated with group (MND; control), motor neuron predominance (upper; lower), onset (bulbar; spinal), and swallow task (thin, pudding) were evaluated and visualized. Pharyngeal swallowing mechanics differed significantly in patients with MND compared with healthy controls (D = 2.01, p mechanics by motor neuron predominance (D = 5.03, p mechanics of patients with MND differ from and are more heterogeneous than healthy controls. These findings suggest patients with MND may compensate reductions in pharyngeal shortening and tongue base retraction by extending the head and neck and increasing hyolaryngeal excursion. This work and further CASM investigations will lead to further insights into development and evaluation of targeted clinical treatments designed to prolong safe and efficient swallowing function in patients with MND.

Investigation of control law reconfigurations to accommodate a control element failure on a commercial airplane

Science.gov (United States)

Ostroff, A. J.; Hueschen, R. M.

1984-01-01

The ability of a pilot to reconfigure the control surfaces on an airplane after a failure, allowing the airplane to recover to a safe condition, becomes more difficult with increasing airplane complexity. Techniques are needed to stabilize and control the airplane immediately after a failure, allowing the pilot more time to make longer range decisions. This paper presents a baseline design of a discrete multivariable control law using four controls for the longitudinal channel of a B-737. Non-reconfigured and reconfigured control laws are then evaluated, both analytically and by means of a digital airplane simulation, for three individual control element failures (stabilizer, elevator, spoilers). The simulation results are used to evaluate the effectiveness of the control reconfiguration on tracking ability during the approach and landing phase of flight with severe windshear and turbulence disturbing the airplane dynamics.

Pilot power based rate control in CDMA 2000 1x EV-DO Rev-A

Institute of Scientific and Technical Information of China (English)

LIU Xiao-feng; GU Jian; YANG Hong-wen

2008-01-01

This article proposes a new algorithm to improvethe rate control efficiency of enhanced reverse link mediumaccess control (RLMAC) in the code division multiple access(CDMA) lx EV-DO release A(Rev. A) system. The newalgorithm brings reverse access terminal (AT) pilot power tothe RLMAC rate control procedure and makes it easier for alow pilot power user to increase its data rate when the systemis slightly loaded and harder to decrease its date rate when thesystem is heavily loaded. Numerical results of system levelsimulations show that the new algorithm can bring highersystem throughput, lower AT transmission power, and lowersystem load.

A Pilot Qualitative Investigation of Stakeholders’ Experiences and Opinions of Equine Insect Bite Hypersensitivity in England

Directory of Open Access Journals (Sweden)

Hannah R. Lomas

2018-01-01

Full Text Available Equine insect bite hypersensitivity (IBH, commonly known as sweet itch or summer eczema, is a frustrating recurrent skin disease in the equine industry involving an immune reaction to the bites of Culicoides spp. midges. To investigate the impact of IBH in the field, an exploratory pilot study was conducted with equine stakeholders in one region of central England. Nine semi-structured, face-to-face interviews were conducted with horse owners and an equine veterinarian. The aim was to gain an understanding of experiences with IBH, and to gauge opinions on the value of the various management strategies horse owners use to control IBH. Awareness of IBH was generally high, particularly in those individuals who had previous experience with the condition. Those with previous experience of IBH commented on the significant effect on daily routines, and the associated cost implications. Most participants supported an integrated approach to hypersensitivity management, and this most commonly involved a combination of physical barriers and chemical repellents, but sometimes included feed supplementation. Overall, attitudes towards IBH suggested that the condition is a notable welfare and economic concern for stakeholders, but veterinary involvement tended to only be in more severe cases. Further research is required in the future to improve understanding, management and potential treatment of this condition.

A Usability and Learnability Case Study of Glass Flight Deck Interfaces and Pilot Interactions through Scenario-based Training

Science.gov (United States)

De Cino, Thomas J., II

In the aviation industry, digitally produced and presented flight, navigation, and aircraft information is commonly referred to as glass flight decks. Glass flight decks are driven by computer-based subsystems and have long been a part of military and commercial aviation sectors. Over the past 15 years, the General Aviation (GA) sector of the aviation industry has become a recent beneficiary of the rapid advancement of computer-based glass flight deck (GFD) systems. While providing the GA pilot considerable enhancements in the quality of information about the status and operations of the aircraft, training pilots on the use of glass flight decks is often delivered with traditional methods (e.g. textbooks, PowerPoint presentations, user manuals, and limited computer-based training modules). These training methods have been reported as less than desirable in learning to use the glass flight deck interface. Difficulties in achieving a complete understanding of functional and operational characteristics of the GFD systems, acquiring a full understanding of the interrelationships of the varied subsystems, and handling the wealth of flight information provided have been reported. Documented pilot concerns of poor user experience and satisfaction, and problems with the learning the complex and sophisticated interface of the GFD are additional issues with current pilot training approaches. A case study was executed to explore ways to improve training using GFD systems at a Midwestern aviation university. The researcher investigated if variations in instructional systems design and training methods for learning glass flight deck technology would affect the perceptions and attitudes of pilots of the learnability (an attribute of usability) of the glass flight deck interface. Specifically, this study investigated the effectiveness of scenario-based training (SBT) methods to potentially improve pilot knowledge and understanding of a GFD system, and overall pilot user

An Investigation of the Impact of Aerodynamic Model Fidelity on Close-In Combat Effectiveness Prediction in Piloted Simulation

Science.gov (United States)

Persing, T. Ray; Bellish, Christine A.; Brandon, Jay; Kenney, P. Sean; Carzoo, Susan; Buttrill, Catherine; Guenther, Arlene

2005-01-01

Several aircraft airframe modeling approaches are currently being used in the DoD community for acquisition, threat evaluation, training, and other purposes. To date there has been no clear empirical study of the impact of airframe simulation fidelity on piloted real-time aircraft simulation study results, or when use of a particular level of fidelity is indicated. This paper documents a series of piloted simulation studies using three different levels of airframe model fidelity. This study was conducted using the NASA Langley Differential Maneuvering Simulator. Evaluations were conducted with three pilots for scenarios requiring extensive maneuvering of the airplanes during air combat. In many cases, a low-fidelity modified point-mass model may be sufficient to evaluate the combat effectiveness of the aircraft. However, in cases where high angle-of-attack flying qualities and aerodynamic performance are a factor or when precision tracking ability of the aircraft must be represented, use of high-fidelity models is indicated.

Complexity and Pilot Workload Metrics for the Evaluation of Adaptive Flight Controls on a Full Scale Piloted Aircraft

Science.gov (United States)

Hanson, Curt; Schaefer, Jacob; Burken, John J.; Larson, David; Johnson, Marcus

2014-01-01

Flight research has shown the effectiveness of adaptive flight controls for improving aircraft safety and performance in the presence of uncertainties. The National Aeronautics and Space Administration's (NASA)'s Integrated Resilient Aircraft Control (IRAC) project designed and conducted a series of flight experiments to study the impact of variations in adaptive controller design complexity on performance and handling qualities. A novel complexity metric was devised to compare the degrees of simplicity achieved in three variations of a model reference adaptive controller (MRAC) for NASA's F-18 (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) Full-Scale Advanced Systems Testbed (Gen-2A) aircraft. The complexity measures of these controllers are also compared to that of an earlier MRAC design for NASA's Intelligent Flight Control System (IFCS) project and flown on a highly modified F-15 aircraft (McDonnell Douglas, now The Boeing Company, Chicago, Illinois). Pilot comments during the IRAC research flights pointed to the importance of workload on handling qualities ratings for failure and damage scenarios. Modifications to existing pilot aggressiveness and duty cycle metrics are presented and applied to the IRAC controllers. Finally, while adaptive controllers may alleviate the effects of failures or damage on an aircraft's handling qualities, they also have the potential to introduce annoying changes to the flight dynamics or to the operation of aircraft systems. A nuisance rating scale is presented for the categorization of nuisance side-effects of adaptive controllers.

Nuclear power plant control room task analysis. Pilot study for pressurized water reactors

International Nuclear Information System (INIS)

Barks, D.B.; Kozinsky, E.J.; Eckel, S.

1982-05-01

The purposes of this nuclear plant task analysis pilot study: to demonstrate the use of task analysis techniques on selected abnormal or emergency operation events in a nuclear power plant; to evaluate the use of simulator data obtained from an automated Performance Measurement System to supplement and validate data obtained by traditional task analysis methods; and to demonstrate sample applications of task analysis data to address questions pertinent to nuclear power plant operational safety: control room layout, staffing and training requirements, operating procedures, interpersonal communications, and job performance aids. Five data sources were investigated to provide information for a task analysis. These sources were (1) written operating procedures (event-based); (2) interviews with subject matter experts (the control room operators); (3) videotapes of the control room operators (senior reactor operators and reactor operators) while responding to each event in a simulator; (4) walk-/talk-throughs conducted by control room operators for each event; and (5) simulator data from the PMS

Parent Perception of Two Eye-Gaze Control Technology Systems in Young Children with Cerebral Palsy: Pilot Study.

Science.gov (United States)

Karlsson, Petra; Wallen, Margaret

2017-01-01

Eye-gaze control technology enables people with significant physical disability to access computers for communication, play, learning and environmental control. This pilot study used a multiple case study design with repeated baseline assessment and parents' evaluations to compare two eye-gaze control technology systems to identify any differences in factors such as ease of use and impact of the systems for their young children. Five children, aged 3 to 5 years, with dyskinetic cerebral palsy, and their families participated. Overall, families were satisfied with both the Tobii PCEye Go and myGaze® eye tracker, found them easy to position and use, and children learned to operate them quickly. This technology provides young children with important opportunities for learning, play, leisure, and developing communication.

Investigation of Parameters Affecting Gypsum Dewatering Properties in a Wet Flue Gas Desulphurization Pilot Plant

DEFF Research Database (Denmark)

Hansen, Brian Brun; Kiil, Søren

2012-01-01

of impurities (0.002 M Al2F6; 50 g quartz/L; 0.02 M Al3+, and 0.040 M Mg2+) were investigated. In addition, slurry from a full-scale wet FGD plant, experiencing formation of flat shaped crystals and poor gypsum dewatering properties, was transferred to the pilot plant to test if the plant would now start...... to time. In this work, the particle size distribution, morphology, and filtration rate of wet FGD gypsum formed in a pilot-scale experimental setup, operated in forced oxidation mode, have been studied. The influence of holding tank residence time (10–408 h), solids content (30–169 g/L), and the presence...... to produce low quality gypsum. The crystals formed in the pilot plant, on the basis of the full-scale slurry did, however, show acceptable filtration rates and crystal morphologies closer to the prismatic crystals from after pilot plant experiments with demineralized water. The gypsum slurry filtration rates...

A queueing model of pilot decision making in a multi-task flight management situation

Science.gov (United States)

Walden, R. S.; Rouse, W. B.

1977-01-01

Allocation of decision making responsibility between pilot and computer is considered and a flight management task, designed for the study of pilot-computer interaction, is discussed. A queueing theory model of pilot decision making in this multi-task, control and monitoring situation is presented. An experimental investigation of pilot decision making and the resulting model parameters are discussed.

Experimental investigation of the chemical looping method on a 1 MW pilot plant

International Nuclear Information System (INIS)

Orth, Matthias

2014-01-01

Attempting to counteract the consequences of climate change, leading industrial nations have agreed on reducing their CO 2 emissions significantly. To reach these reduction goals, it is essential to reduce the CO 2 emissions in the field of energy conversion. This PHD thesis covers the field of chemical looping combustion, a technology that uses fossil fuels for energy conversion with inherent capture of CO 2 . Since the research regarding chemical looping had so far focused mainly on lab scale or small scale experiments, a 1 MW pilot plant has been erected at Technische Universitaet Darmstadt in order to investigate the process in a semi-industrial scale and to check the process efficiency with commercially usable equipment. This pilot consists of two interconnected fluidized bed reactors and has an overall height of more than 11 m. In this thesis, some experiments with ilmenite - used as the oxygen carrier - are explained. Furthermore, the design, erection and commissioning of the pilot plant are presented as well as the results of the first test campaigns. The evaluation of the latter proves that the process can be handled in the design configuration and that CO 2 can be safely captured in a pilot plant of this scale.

Centrifuge Study of Pilot Tolerance to Acceleration and the Effects of Acceleration on Pilot Performance

Science.gov (United States)

Creer, Brent Y.; Smedal, Harald A.; Wingrove, Rodney C.

1960-01-01

A research program the general objective of which was to measure the effects of various sustained accelerations on the control performance of pilots, was carried out on the Aviation Medical Acceleration Laboratory centrifuge, U.S. Naval Air Development Center, Johnsville, PA. The experimental setup consisted of a flight simulator with the centrifuge in the control loop. The pilot performed his control tasks while being subjected to acceleration fields such as might be encountered by a forward-facing pilot flying an atmosphere entry vehicle. The study was divided into three phases. In one phase of the program, the pilots were subjected to a variety of sustained linear acceleration forces while controlling vehicles with several different sets of longitudinal dynamics. Here, a randomly moving target was displayed to the pilot on a cathode-ray tube. For each combination of acceleration field and vehicle dynamics, pilot tracking accuracy was measured and pilot opinion of the stability and control characteristics was recorded. Thus, information was obtained on the combined effects of complexity of control task and magnitude and direction of acceleration forces on pilot performance. These tests showed that the pilot's tracking performance deteriorated markedly at accelerations greater than about 4g when controlling a lightly damped vehicle. The tentative conclusion was also reached that regardless of the airframe dynamics involved, the pilot feels that in order to have the same level of control over the vehicle, an increase in the vehicle dynamic stability was required with increases in the magnitudes of the acceleration impressed upon the pilot. In another phase, boundaries of human tolerance of acceleration were established for acceleration fields such as might be encountered by a pilot flying an orbital vehicle. A special pilot restraint system was developed to increase human tolerance to longitudinal decelerations. The results of the tests showed that human tolerance

Effects of Spatio-Temporal Aliasing on Pilot Performance in Active Control Tasks

Science.gov (United States)

Zaal, Peter; Sweet, Barbara

2010-01-01

Spatio-temporal aliasing affects pilot performance and control behavior. For increasing refresh rates: 1) Significant change in control behavior: a) Increase in visual gain and neuromuscular frequency. b) Decrease in visual time delay. 2) Increase in tracking performance: a) Decrease in RMSe. b) Increase in crossover frequency.

Existing Whole-House Solutions Case Study: Greenbelt Homes, Inc. Pilot Retrofit Project

Energy Technology Data Exchange (ETDEWEB)

None

2015-06-01

In the fall of 2010, a multiyear pilot energy efficiency retrofit project was undertaken by Greenbelt Homes, Inc., (GHI) a 1,566 home cooperative of circa 1930 and 1940 homes in Greenbelt, Maryland. GHI established this pilot project to serve as a basis for decision making for the rollout of a community-wide upgrade program that will incorporate energy efficiency improvements to the building envelope and mechanical equipment. With the community upgrade fully funded by the cooperative through their membership without outside subsidies, this project presents a unique opportunity to evaluate and prioritize the wide range of benefits of high-performance retrofits based on member experience with and acceptance of the retrofit measures implemented during the pilot project. Addressing the complex interactions between benefits, trade-offs, construction methods, project management implications, realistic upfront costs, financing, and other considerations, serves as a case study for energy retrofit projects that include high-performance technologies based on the long-term value to the homeowner. The pilot project focused on identifying the added costs and energy-savings benefits of improvements. Phase 1—baseline evaluation for a representative set of 28 homes sited in seven buildings; Phase 2—installation of the building envelope improvements and continued monitoring of the energy consumption for the heating season; Phase 3—energy simulations supporting recommendations for HVAC and water heating upgrades.

Ambulatory (24 h) blood pressure and arterial stiffness measurement in Marfan syndrome patients: a case control feasibility and pilot study.

Science.gov (United States)

Hillebrand, Matthias; Nouri, Ghazaleh; Hametner, Bernhard; Parragh, Stephanie; Köster, Jelena; Mortensen, Kai; Schwarz, Achim; von Kodolitsch, Yskert; Wassertheurer, Siegfried

2016-05-06

The aim of this work is the investigation of measures of ambulatory brachial and aortic blood pressure and indices of arterial stiffness and aortic wave reflection in Marfan patients. A case-control study was conducted including patients with diagnosed Marfan syndrome following Ghent2 nosology and healthy controls matched for sex, age and daytime brachial systolic blood pressure. For each subject a 24 h ambulatory blood pressure and 24 h pulse wave analysis measurement was performed. All parameters showed a circadian pattern whereby pressure dipping was more pronounced in Marfan patients. During daytime only Marfan patients with aortic root surgery showed increased pulse wave velocity. In contrast, various nighttime measurements, wave reflection determinants and circadian patterns showed a significant difference. The findings of our study provide evidence that ambulatory measurement of arterial stiffness parameters is feasible and that these determinants are significantly different in Marfan syndrome patients compared to controls in particular at nighttime. Further investigation is therefore indicated.

An Extended Case Study Methoology for Investigating Influence of Cultural, Organizational, and Automation Factors on Human-Automation Trust

Science.gov (United States)

Koltai, Kolina Sun; Ho, Nhut; Masequesmay, Gina; Niedober, David; Skoog, Mark; Johnson, Walter; Cacanindin, Artemio

2014-01-01

This paper discusses a case study that examined the influence of cultural, organizational and automation capability upon human trust in, and reliance on, automation. In particular, this paper focuses on the design and application of an extended case study methodology, and on the foundational lessons revealed by it. Experimental test pilots involved in the research and development of the US Air Forces newly developed Automatic Ground Collision Avoidance System served as the context for this examination. An eclectic, multi-pronged approach was designed to conduct this case study, and proved effective in addressing the challenges associated with the cases politically sensitive and military environment. Key results indicate that the system design was in alignment with pilot culture and organizational mission, indicating the potential for appropriate trust development in operational pilots. These include the low-vulnerabilityhigh risk nature of the pilot profession, automation transparency and suspicion, system reputation, and the setup of and communications among organizations involved in the system development.

Fully automatic guidance and control for rotorcraft nap-of-the-Earth flight following planned profiles. Volume 1: Real-time piloted simulation

Science.gov (United States)

Clement, Warren F.; Gorder, Peter J.; Jewell, Wayne F.

1991-01-01

Developing a single-pilot, all-weather nap-of-the-earth (NOE) capability requires fully automatic NOE (ANOE) navigation and flight control. Innovative guidance and control concepts are investigated in a four-fold research effort that: (1) organizes the on-board computer-based storage and real-time updating of NOE terrain profiles and obstacles in course-oriented coordinates indexed to the mission flight plan; (2) defines a class of automatic anticipative pursuit guidance algorithms and necessary data preview requirements to follow the vertical, lateral, and longitudinal guidance commands dictated by the updated flight profiles; (3) automates a decision-making process for unexpected obstacle avoidance; and (4) provides several rapid response maneuvers. Acquired knowledge from the sensed environment is correlated with the forehand knowledge of the recorded environment (terrain, cultural features, threats, and targets), which is then used to determine an appropriate evasive maneuver if a nonconformity of the sensed and recorded environments is observed. This four-fold research effort was evaluated in both fixed-based and moving-based real-time piloted simulations, thereby, providing a practical demonstration for evaluating pilot acceptance of the automated concepts, supervisory override, manual operation, and re-engagement of the automatic system. Volume one describes the major components of the guidance and control laws as well as the results of the piloted simulations. Volume two describes the complete mathematical model of the fully automatic guidance system for rotorcraft NOE flight following planned flight profiles.

Autogenic Feedback Training Exercise and pilot performance: enhanced functioning under search-and-rescue flying conditions

Science.gov (United States)

Cowings, P. S.; Kellar, M. A.; Folen, R. A.; Toscano, W. B.; Burge, J. D.

2001-01-01

Studies have shown that autonomous mode behavior is one cause of aircraft fatalities due to pilot error. In such cases, the pilot is in a high state of psychological and physiological arousal and tends to focus on one problem, while ignoring more critical information. This study examined the effect of training in physiological self-recognition and regulation, as a means of improving crew cockpit performance. Seventeen pilots were assigned to the treatment and control groups matched for accumulated flight hours. The treatment group contained 4 pilots from HC-130 Hercules aircraft and 4 HH-65 Dolphin helicopter pilots; the control group contained 3 pilots of HC-130s and 6 helicopter pilots. During an initial flight, physiological data were recorded on each crewmember and an instructor pilot rated individual crew performance. Eight crewmembers were then taught to regulate their own physiological response levels using Autogenic-Feedback Training Exercise (AFTE). The remaining participants received no training. During a second flight, treatment participants showed significant improvement in performance (rated by the same instructor pilot as in pretests) while controls did not improve. The results indicate that AFTE management of high states of physiological arousal may improve pilot performance during emergency flying conditions.

Autorotation flight control system

Science.gov (United States)

Bachelder, Edward N. (Inventor); Lee, Dong-Chan (Inventor); Aponso, Bimal L. (Inventor)

2011-01-01

The present invention provides computer implemented methodology that permits the safe landing and recovery of rotorcraft following engine failure. With this invention successful autorotations may be performed from well within the unsafe operating area of the height-velocity profile of a helicopter by employing the fast and robust real-time trajectory optimization algorithm that commands control motion through an intuitive pilot display, or directly in the case of autonomous rotorcraft. The algorithm generates optimal trajectories and control commands via the direct-collocation optimization method, solved using a nonlinear programming problem solver. The control inputs computed are collective pitch and aircraft pitch, which are easily tracked and manipulated by the pilot or converted to control actuator commands for automated operation during autorotation in the case of an autonomous rotorcraft. The formulation of the optimal control problem has been carefully tailored so the solutions resemble those of an expert pilot, accounting for the performance limitations of the rotorcraft and safety concerns.

Early Glycemic Control in Critically Ill Emergency Department Patients: Pilot Trial

Directory of Open Access Journals (Sweden)

Cohen, Jason

2010-02-01

Full Text Available Objective: Glycemic control in the critically ill intensive care unit (ICU patient has been shown to improve morbidity and mortality. We sought to investigate the effect of early glycemic control in critically ill emergency department (ED patients in a small pilot trial.Methods: Adult non-trauma, non-pregnant ED patients presenting to a university tertiary referral center and identified as critically ill were eligible for enrollment on a convenience basis. Critical illness was determined upon assignment for ICU admission. Patients were randomized to either ED standard care or glycemic control. Glycemic control involved use of an insulin drip to maintain blood glucose levels between 80-140 mg/dL. Glycemic control continued until ED discharge. Standard patients were managed at ED attending physician discretion. We assessed severity of illness by calculation of APACHE II score. The primary endpoint was in-hospital mortality. Secondary endpoints included vasopressor requirement, hospital length of stay, and mechanical ventilation requirement.Results: Fifty patients were randomized, 24 to the glycemic group and 26 to the standard care cohort. Four of the 24 patients (17% in the treatment arm did not receive insulin despite protocol requirements. While receiving insulin, three of 24 patients (13% had an episode of hypoglycemia. By chance, the patients in the treatment group had a trend toward higher acuity by APACHE II scores. Patient mortality and morbidity were similar despite the acuity difference.Conclusion: There was no difference in morbidity and mortality between the two groups. The benefit of glycemic control may be subject to source of illness and to degree of glycemic control, or have no effect. Such questions bear future investigation. [West J Emerg Med. 2010; 11(1:20-23].

Clinician–Investigator Training and the Need to Pilot New Approaches to Recruiting and Retaining This Workforce

Science.gov (United States)

Hall, Alison K.; Lund, P. Kay

2017-01-01

Clinician–investigators, also called physician–scientists, offer critical knowledge and perspectives that benefit research on basic science mechanisms, improved diagnostic and therapeutic approaches, population and outcomes medicine, health policy, and health services, yet few clinically trained health professionals pursue a research career. Sustaining this workforce requires attention to the unique challenges faced by investigators who must achieve clinical and research competence during training and their careers. These challenges include the duration of required clinical training, limited or discontinuous research opportunities, high levels of educational debt, balancing the dual obligations and rewards of clinical care and research, competition for research funding, and the need for leadership development after training. Women and individuals from underrepresented racial and ethnic groups comprise a small percentage of this workforce. The authors summarize the recent literature on training for clinician–investigators, emphasizing approaches with encouraging outcomes that warrant broader implementation. Using this overview as background, they convened three workshops at the National Institutes of Health in 2016 to identify and refine key priorities for potential new pilot programs to recruit and retain the clinician–investigator workforce. From these workshops emerged three priorities for future pilot programs: (1) support for research in residency, (2) new research on-ramps for health professionals at multiple career stages, and (3) national networks to diversify and sustain clinician–investigator faculty. Implementation of any pilot program will require coordinated commitment from academic health centers, medical licensing/certification boards, professional societies, and clinician–investigators themselves, in addition to support from the National Institutes of Health. PMID:28767499

Clinician-Investigator Training and the Need to Pilot New Approaches to Recruiting and Retaining This Workforce.

Science.gov (United States)

Hall, Alison K; Mills, Sherry L; Lund, P Kay

2017-10-01

Clinician-investigators, also called physician-scientists, offer critical knowledge and perspectives that benefit research on basic science mechanisms, improved diagnostic and therapeutic approaches, population and outcomes medicine, health policy, and health services, yet few clinically trained health professionals pursue a research career. Sustaining this workforce requires attention to the unique challenges faced by investigators who must achieve clinical and research competence during training and their careers. These challenges include the duration of required clinical training, limited or discontinuous research opportunities, high levels of educational debt, balancing the dual obligations and rewards of clinical care and research, competition for research funding, and the need for leadership development after training. Women and individuals from underrepresented racial and ethnic groups comprise a small percentage of this workforce.The authors summarize the recent literature on training for clinician-investigators, emphasizing approaches with encouraging outcomes that warrant broader implementation. Using this overview as background, they convened three workshops at the National Institutes of Health in 2016 to identify and refine key priorities for potential new pilot programs to recruit and retain the clinician-investigator workforce. From these workshops emerged three priorities for future pilot programs: (1) support for research in residency, (2) new research on-ramps for health professionals at multiple career stages, and (3) national networks to diversify and sustain clinician-investigator faculty. Implementation of any pilot program will require coordinated commitment from academic health centers, medical licensing/certification boards, professional societies, and clinician-investigators themselves, in addition to support from the National Institutes of Health.

Wind-tunnel investigation of an armed mini remotely piloted vehicle. [conducted in Langley V/STOL tunnel

Science.gov (United States)

Phelps, A. E., III

1979-01-01

A wind tunnel investigation of a full scale remotely piloted vehicle (RPV) armed with rocket launchers was conducted. The model had unacceptable longitudinal stability characteristics at negative angles of attack in the original design configuration. The addition of a pair of fins mounted in a V arrangement on the propeller shroud resulted in a configuration with acceptable longitudinal stability characteristics. The addition of wing mounted external stores to the modified configuration resulted in a slight reduction in the longitudinal stability. The lateral directional characteristics of the model were generally good, but the model had low directional stability at low angles of attack. Aerodynamic control power was very strong around all three axes.

High intensity interior aircraft noise increases the risk of high diastolic blood pressure in Indonesian Air Force pilots

Directory of Open Access Journals (Sweden)

Minarma Siagian

2009-12-01

Full Text Available Aim: To analyze the effects of aircraft noise, resting pulse rate, and other factors on the risk of high diastolic blood pressure (DBP in Indonesian Air Force pilots.Methods: A nested case-control study was conducted using data extracted from annual medical check-ups indoctrination aerophysiologic training records at the Saryanto Aviation and Aerospace Health Institute (LAKESPRA in Jakarta from January 2003 – September 2008. For analysis of DBP: the case group with DBP ≥ 90 mmHg were compared with contral group with DBP < 79 mmHG. One case matched to 12 controls.Results: Out of 567 pilots, 544 (95.9% had complete medical records. For this analysis there were 40 cases of high DBP and 480 controls for DBP. Pilots exposed to aircraft noise 90-95 dB rather than 70-80 dB had a 2.7-fold increase for high DBP [adjusted odds ratio (ORa = 2.70; 95% confi dence interval (CI = 1.05-6.97]. Pilots with resting pulse rates of ≥ 81/minute rather than ≤ 80/minute had a 2.7-fold increase for high DBP (ORa = 2.66; 95% CI = 1.26-5.61. In terms of total fl ight hours, pilots who had 1401-11125 hours rather than 147-1400 hours had a 3.2-fold increase for high DBP (ORa = 3.18; 95% CI = 1.01-10.03.Conclusion: High interior aircraft noise, high total flight hours,  and high resting pulse rate, increased risk for high DBP. Self assessment of resting pulse rate can be used to control the risk of high DBP. (Med J Indones 2009; 276: 276-82Keywords: diastolic blood pressure, aircraft noise, resting pulse rate, military pilots

Comparison of in-flight and ground-based simulator derived flying qualities and pilot performance for approach and landing tasks

Science.gov (United States)

Grantham, William D.; Williams, Robert H.

1987-01-01

For the case of an approach-and-landing piloting task emphasizing response to the landing flare, pilot opinion and performance parameters derived from jet transport aircraft six-degree-of-freedom ground-based and in-flight simulators were compared in order to derive data for the flight-controls/flying-qualities engineers. The data thus obtained indicate that ground simulation results tend to be conservative, and that the effect of control sensitivity is more pronounced for ground simulation. The pilot also has a greater tendency to generate pilot-induced oscillation in ground-based simulation than in flight.

Factors associated with suicide: Case-control study in South Tyrol.

Science.gov (United States)

Giupponi, Giancarlo; Innamorati, Marco; Baldessarini, Ross J; De Leo, Diego; de Giovannelli, Francesca; Pycha, Roger; Conca, Andreas; Girardi, Paolo; Pompili, Maurizio

2018-01-01

As suicide is related to many factors in addition to psychiatric illness, broad and comprehensive risk-assessment for risk of suicide is required. This study aimed to differentiate nondiagnostic risk factors among suicides versus comparable psychiatric patients without suicidal behavior. We carried out a pilot, case-control comparison of 131 cases of suicide in South Tyrol matched for age and sex with 131 psychiatric controls, using psychological autopsy methods to evaluate differences in clinically assessed demographic, social, and clinical factors, using bivariate conditional Odds Risk comparisons followed by conditional regression modeling controlled for ethnicity. Based on multivariable conditional regression modeling, suicides were significantly more likely to have experienced risk factors, ranking as: [a] family history of suicide or attempt≥[b] recent interpersonal stressors≥[c] childhood traumatic events≥[d] lack of recent clinician contacts≥[e] previous suicide attempt≥[f] non-Italian ethnicity, but did not differ in education, marital status, living situation, or employment, nor by psychiatric or substance-abuse diagnoses. Both recent and early factors were associated with suicide, including lack of recent clinical care, non-Italian cultural subgroup-membership, familial suicidal behavior, and recent interpersonal distress. Copyright © 2017 Elsevier Inc. All rights reserved.

The effects of risk perception and flight experience on airline pilots' locus of control with regard to safety operation behaviors.

Science.gov (United States)

You, Xuqun; Ji, Ming; Han, Haiyan

2013-08-01

The primary objective of this paper was to integrate two research traditions, social cognition approach and individual state approach, and to understand the relationships between locus of control (LOC), risk perception, flight time, and safety operation behavior (SOB) among Chinese airline pilots. The study sample consisted of 193 commercial airline pilots from China Southern Airlines Ltd. The results showed that internal locus of control directly affected pilot safety operation behavior. Risk perception seemed to mediate the relationship between locus of control and safety operation behaviors, and total flight time moderated internal locus of control. Thus, locus of control primarily influences safety operation behavior indirectly by affecting risk perception. The total effect of internal locus of control on safety behaviors is larger than that of external locus of control. Furthermore, the safety benefit of flight experience is more pronounced among pilots with high internal loci of control in the early and middle flight building stages. Practical implications for aviation safety and directions for future research are also discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

An Investigation of Rotorcraft Stability-Phase Margin Requirements in Hover

Science.gov (United States)

Blanken, Chris L.; Lusardi, Jeff A.; Ivler, Christina M.; Tischler, Mark B.; Hoefinger, Marc T.; Decker, William A.; Malpica, Carlos A.; Berger, Tom; Tucker, George E.

2009-01-01

A cooperative study was performed to investigate the handling quality effects from reduced flight control system stability margins, and the trade-offs with higher disturbance rejection bandwidth (DRB). The piloted simulation study, perform on the NASA-Ames Vertical Motion Simulator, included three classes of rotorcraft in four configurations: a utility-class helicopter; a medium-lift helicopter evaluated with and without an external slung load; and a large (heavy-lift) civil tiltrotor aircraft. This large aircraft also allowed an initial assessment of ADS-33 handling quality requirements for an aircraft of this size. Ten experimental test pilots representing the U.S. Army, Marine Corps, NASA, rotorcraft industry, and the German Aerospace Center (DLR), evaluated the four aircraft configurations, for a range of flight control stability-margins and turbulence levels, while primarily performing the ADS-33 Hover and Lateral Reposition MTEs. Pilot comments and aircraft-task performance data were analyzed. The preliminary stability margin results suggest higher DRB and less phase margin cases are preferred as the aircraft increases in size. Extra care will need to be taken to assess the influence of variability when nominal flight control gains start with reduced margins. Phase margins as low as 20-23 degrees resulted in low disturbance-response damping ratios, objectionable oscillations, PIO tendencies, and a perception of an incipient handling qualities cliff. Pilot comments on the disturbance response of the aircraft correlated well to the DRB guidelines provided in the ADS-33 Test Guide. The A D-3S3 mid-term response-to-control damping ratio metrics can be measured and applied to the disturbance-response damping ratio. An initial assessment of LCTR yaw bandwidth shows the current Level 1 boundary needs to be relaxed to help account for a large pilot off-set from the c.g. Future efforts should continue to investigate the applicability/refinement of the current ADS-33

An Investigation of Sensory Information, Levels of Automation, and Piloting Experience on Unmanned Aircraft Pilot Performance

Science.gov (United States)

2012-03-01

Development.of. NASA - TLX .(Task.Load.Index):.Results.of.empiri- cal.and.theoretical.research ..In.P .A ..Hancock.&.N .. Meshkati.(Eds .),.Human...8 Automated Manual Level of Automation Hi gh Z oo m M an ip ul at io n Pilot Non-pilot Figure 4. Number of participants with high levels of zoom

The Rorschach test and Gilles de la Tourette's syndrome: a pilot case-control study.

Science.gov (United States)

Balottin, Umberto; Rossi, Maura; Rossi, Giorgio; Viganò, Lucia; Nanti, Marta; Salini, Silvia; Lanzi, Giovanni; Termine, Cristiano

2009-10-01

To date only three studies, all lacking a control group, have investigated the personality style underlying tic disorders or Tourette's syndrome (TS), using the projective Rorschach test. Despite the recent controversy about its proper use in clinical practice and research, the Rorschach test may be useful to explore personality organization in TS. The research hypothesis under investigation in this exploratory study was that young TS patients exhibit a peculiar personality organization, with significantly increased indicators of poor emotional control, aggression, anxiety and depression, on the Rorschach test, compared to healthy controls. We analyed the Rorschach protocols of 17 newly diagnosed paediatric TS patients and 17 age- and sex-matched healthy controls. Compared with the controls young TS patients recorded significantly lower mean percentages of F and F+ responses and a significantly higher number of FM and FC responses, thus showing reduced control of emotions and difficulty in integrating aggressivity. Furthermore, associations emerged between comorbidity with ADHD and increased emotional instability and between severity of tics and of OCD and a pattern of emotional hyper-control and application of rigid defensive mechanisms. These results seem to confirm the existence of a peculiar personality style in young TS patients and may have important implications, both pathogenetic and therapeutic.

Recruitment and accrual of women in a placebo-controlled clinical pilot study on manual therapy.

Science.gov (United States)

Cambron, Jerrilyn A; Hawk, Cheryl; Evans, Roni; Long, Cynthia R

2004-06-01

To investigate the accrual rates and recruitment processes among 3 Midwestern sites during a pilot study on manual therapy for chronic pelvic pain. Multisite pilot study for a randomized, placebo-controlled clinical trial. Three chiropractic institutions in or near major metropolitan cities in the Midwestern United States. Thirty-nine women aged 18 to 45 with chronic pelvic pain of at least 6 months duration, diagnosed by a board certified gynecologist. The method of recruitment was collected for each individual who responded to an advertisement and completed an interviewer-administered telephone screen. Participants who were willing and eligible after 3 baseline visits were entered into a randomized clinical trial. The number of responses and accrual rates were determined for the overall study, each of the 3 treatment sites, and each of the 5 recruitment efforts. In this study, 355 women were screened over the telephone and 39 were randomized, making the rate of randomization approximately 10%. The most effective recruitment methods leading to randomization were direct mail (38%) and radio advertisements (34%). However, success of the recruitment process differed by site. Based on the accrual of this multisite pilot study, a full-scale trial would not be feasible using this study's parameters. However, useful information was gained on recruitment effectiveness, eligibility criteria, and screening protocols among the 3 metropolitan sites.

Closed-loop, pilot/vehicle analysis of the approach and landing task

Science.gov (United States)

Anderson, M. R.; Schmidt, D. K.

1986-01-01

In the case of approach and landing, it is universally accepted that the pilot uses more than one vehicle response, or output, to close his control loops. Therefore, to model this task, a multi-loop analysis technique is required. The analysis problem has been in obtaining reasonable analytic estimates of the describing functions representing the pilot's loop compensation. Once these pilot describing functions are obtained, appropriate performance and workload metrics must then be developed for the landing task. The optimal control approach provides a powerful technique for obtaining the necessary describing functions, once the appropriate task objective is defined in terms of a quadratic objective function. An approach is presented through the use of a simple, reasonable objective function and model-based metrics to evaluate loop performance and pilot workload. The results of an analysis of the LAHOS (Landing and Approach of Higher Order Systems) study performed by R.E. Smith is also presented.

The Propulsive-Only Flight Control Problem

Science.gov (United States)

Blezad, Daniel J.

1996-01-01

Attitude control of aircraft using only the throttles is investigated. The long time constants of both the engines and of the aircraft dynamics, together with the coupling between longitudinal and lateral aircraft modes make piloted flight with failed control surfaces hazardous, especially when attempting to land. This research documents the results of in-flight operation using simulated failed flight controls and ground simulations of piloted propulsive-only control to touchdown. Augmentation control laws to assist the pilot are described using both optimal control and classical feedback methods. Piloted simulation using augmentation shows that simple and effective augmented control can be achieved in a wide variety of failed configurations.

Investigation to identify a resource-efficient case-control methodology for determining antibiotics associated with Clostridium difficile infection.

Science.gov (United States)

Chung, Philip; Currie, Brian; Guo, Yi; Talansky, Moshe; Brown, Shakara; Ostrowsky, Belinda

2014-10-01

Antimicrobial exposure remains an important risk factor for developing Clostridium difficile infection (CDI). Efficient method to identify antibiotics associated with CDI is important for formulating strategies to curtail their use. As a prelude to a more extensive Agency for Healthcare Research and Quality-funded project (Evaluation & Research on Antimicrobial Stewardship's Effect on Clostridium difficile), we undertook an exploratory evaluation to determine a resource-efficient method for identifying antibiotic targets for antimicrobial stewardship interventions. The study compared a series of 6 focused case-control studies. Cases consisted of patients with laboratory-confirmed CDI admitted from July-October 2009. Controls were selected from patients without CDI hospitalized during the same period. Five groups of controls were matched to cases (2:1 ratio) using group-specific matching criteria, including admission date, age, type of admission, length of stay (LOS) to discharge, and/or LOS to CDI diagnosis. The final control group was selected from patients who received antibiotics during hospitalization. Data, including demographics and antibiotic usage, were compared between case and control groups. A total of 126 cases were matched to 6 groups of 252 controls. For control groups 1-5, the use of piperacillin and tazobactam, ceftriaxone or cefepime, ciprofloxacin or moxifloxacin, intravenous vancomycin, azithromycin, and antibiotics of last resort were significantly more frequent in case than control patients. For the final control group, the associations between ceftriaxone or cefepime, and ciprofloxacin or moxifloxacin use and CDI no longer persisted. This could in part be explained by differences in comorbidities between case and control patients even with stringent matching criteria. Use of a simple matching strategy to conduct case-control studies is an efficient and feasible compromise strategy, especially in resource-limited settings, to identify high

Remotely Piloted Vehicles for Experimental Flight Control Testing

Science.gov (United States)

Motter, Mark A.; High, James W.

2009-01-01

A successful flight test and training campaign of the NASA Flying Controls Testbed was conducted at Naval Outlying Field, Webster Field, MD during 2008. Both the prop and jet-powered versions of the subscale, remotely piloted testbeds were used to test representative experimental flight controllers. These testbeds were developed by the Subsonic Fixed Wing Project s emphasis on new flight test techniques. The Subsonic Fixed Wing Project is under the Fundamental Aeronautics Program of NASA's Aeronautics Research Mission Directorate (ARMD). The purpose of these testbeds is to quickly and inexpensively evaluate advanced concepts and experimental flight controls, with applications to adaptive control, system identification, novel control effectors, correlation of subscale flight tests with wind tunnel results, and autonomous operations. Flight tests and operator training were conducted during four separate series of tests during April, May, June and August 2008. Experimental controllers were engaged and disengaged during fully autonomous flight in the designated test area. Flaps and landing gear were deployed by commands from the ground control station as unanticipated disturbances. The flight tests were performed NASA personnel with support from the Maritime Unmanned Development and Operations (MUDO) team of the Naval Air Warfare Center, Aircraft Division

Pilot-scale cooling tower to evaluate corrosion, scaling, and biofouling control strategies for cooling system makeup water.

Science.gov (United States)

Chien, S H; Hsieh, M K; Li, H; Monnell, J; Dzombak, D; Vidic, R

2012-02-01

Pilot-scale cooling towers can be used to evaluate corrosion, scaling, and biofouling control strategies when using particular cooling system makeup water and particular operating conditions. To study the potential for using a number of different impaired waters as makeup water, a pilot-scale system capable of generating 27,000 kJ∕h heat load and maintaining recirculating water flow with a Reynolds number of 1.92 × 10(4) was designed to study these critical processes under conditions that are similar to full-scale systems. The pilot-scale cooling tower was equipped with an automatic makeup water control system, automatic blowdown control system, semi-automatic biocide feeding system, and corrosion, scaling, and biofouling monitoring systems. Observed operational data revealed that the major operating parameters, including temperature change (6.6 °C), cycles of concentration (N = 4.6), water flow velocity (0.66 m∕s), and air mass velocity (3660 kg∕h m(2)), were controlled quite well for an extended period of time (up to 2 months). Overall, the performance of the pilot-scale cooling towers using treated municipal wastewater was shown to be suitable to study critical processes (corrosion, scaling, biofouling) and evaluate cooling water management strategies for makeup waters of complex quality.

Breast cancer and personal environmental risk factors in Marin County - Pilot study

Energy Technology Data Exchange (ETDEWEB)

Erdmann, C.A.; Farren, G.; Baltzell, K.; Chew, T.; Clarkson, C.; Fleshman, R.; Leary, C.; Mizroch, M.; Orenstein, F.; Russell, M.L.; Souders-Mason, V.; Wrensch, M.

2003-02-01

The purpose of the Personal Environmental Risk Factor Study (PERFS) pilot project was to develop methodologies and a questionnaire for a future population-based case-control study to investigate the role of selected environmental exposures in breast cancer development. Identification of etiologically relevant exposures during a period of potential vulnerability proximate to disease onset offers the possibility of clinical disease prevention even when disease initiation may have already occurred many years earlier. Certain personal environmental agents or combinations of agents may influence disease promotion. Therefore, this pilot study focused on exposures that occurred during the ten-year period prior to diagnosis for cases and the last ten years for controls, rather than more historic exposures. For this pilot study, they used a community-based research approach. In the collaborative efforts, community members participated with academic researchers in all phases of the research, including research question identification, study design, development of research tools, development of the human subjects protocol, and report writing. Community member inclusion was based upon the concept that community participation could improve the relevance of scientific studies and ultimate success of the research by encouraging an ongoing dialogue between community members and academic representatives. Early activities of this project focused on the collection of input from the community regarding the possible role of environmental factors in the incidence of breast cancer in Marin County. The intent was to inform the scientists of community concerns, enhance the research team's understanding of the community being studied, and provide interested community members with a better understanding of the strengths and weaknesses of traditional research methods through active participation in the research process.

Association Between Anemia and Cerebral Venous Thrombosis: Case-Control Study

NARCIS (Netherlands)

Coutinho, Jonathan M.; Zuurbier, Susanna M.; Gaartman, Aafke E.; Dikstaal, Arienne A.; Stam, Jan; Middeldorp, Saskia; Cannegieter, Suzanne C.

2015-01-01

Anemia is often considered to be a risk factor for cerebral venous thrombosis (CVT), but this assumption is mostly based on case reports. We investigated the association between anemia and CVT in a controlled study. Unmatched case-control study: cases were adult patients with CVT included in a

The relationship between manual handling performance and recent flying experience in air transport pilots.

Science.gov (United States)

Ebbatson, Matt; Harris, Don; Huddlestone, John; Sears, Rodney

2010-02-01

Modern jet transport aircraft are typically flown using the on-board automation by the pilot programming commands into the auto-flight systems. Anecdotal evidence exists suggesting that pilots of highly automated aircraft experience manual flying skills decay as a result of a lack of opportunity to practise hand-flying during line operations. The ability of a pilot to revert to basic manual control is essential, for example, in cases where the aircraft's automatic capability is diminished or when reconfiguring the automatics is an ineffective use of crew capacity. However, there is a paucity of objective data to substantiate this perceived threat to flight safety. Furthermore, traditional performance measurement techniques may lack the ability to identify subtle but significant differences in pilots' manual handling ability in large transport aircraft. This study examines the relationship between pilot manual handling performance and their recent flying experience using both traditional flight path tracking measures and frequency-based control strategy measures. Significant relationships are identified between pilots' very recent flying experience and their manual control strategy. Statement of Relevance: The study demonstrates a novel application of frequency analysis, which produces a broader and more sensitive analysis of pilot performance than has been offered in previous research. Additionally, the relationships that are found to exist between recent flying experience and manual flying performance will help to guide future pilot assessment and training.

Pilot investigation - Nominal crew induced forces in zero-g

Science.gov (United States)

Klute, Glenn K.

1992-01-01

This report presents pilot-study data of test subject forces induced by intravehicular activities such as push-offs and landings with both hands and feet. Five subjects participated in this investigation. Three orthogonal force axes were measured in the NASA KC-135 research aircraft's 'zero-g' environment. The largest forces were induced during vertical foot push-offs, including one of 534 newtons (120 lbs). The mean vertical foot push-off was 311 newtons (70 lbs). The vertical hand push-off forces were also relatively large, including one of 267 newtons (60 lbs) with a mean of 151 newtons (34 lbs). These force magnitudes of these forces would result in a Shuttle gravity environment of about 1 x exp 10 -4 g's.

First human rabies case in French Guiana, 2008: epidemiological investigation and control.

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Jean-Baptiste Meynard

Full Text Available BACKGROUND: Until 2008, human rabies had never been reported in French Guiana. On 28 May 2008, the French National Reference Center for Rabies (Institut Pasteur, Paris confirmed the rabies diagnosis, based on hemi-nested polymerase chain reaction on skin biopsy and saliva specimens from a Guianan, who had never travelled overseas and died in Cayenne after presenting clinically typical meningoencephalitis. METHODOLOGY/PRINCIPAL FINDINGS: Molecular typing of the virus identified a Lyssavirus (Rabies virus species, closely related to those circulating in hematophagous bats (mainly Desmodus rotundus in Latin America. A multidisciplinary Crisis Unit was activated. Its objectives were to implement an epidemiological investigation and a veterinary survey, to provide control measures and establish a communications program. The origin of the contamination was not formally established, but was probably linked to a bat bite based on the virus type isolated. After confirming exposure of 90 persons, they were vaccinated against rabies: 42 from the case's entourage and 48 healthcare workers. To handle that emergence and the local population's increased demand to be vaccinated, a specific communications program was established using several media: television, newspaper, radio. CONCLUSION/SIGNIFICANCE: This episode, occurring in the context of a Department far from continental France, strongly affected the local population, healthcare workers and authorities, and the management team faced intense pressure. This observation confirms that the risk of contracting rabies in French Guiana is real, with consequences for population educational program, control measures, medical diagnosis and post-exposure prophylaxis.

Environment And Genetics in Lung cancer Etiology (EAGLE study: An integrative population-based case-control study of lung cancer

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Colombi Antonio

2008-06-01

Full Text Available Abstract Background Lung cancer is the leading cause of cancer mortality worldwide. Tobacco smoking is its primary cause, and yet the precise molecular alterations induced by smoking in lung tissue that lead to lung cancer and impact survival have remained obscure. A new framework of research is needed to address the challenges offered by this complex disease. Methods/Design We designed a large population-based case-control study that combines a traditional molecular epidemiology design with a more integrative approach to investigate the dynamic process that begins with smoking initiation, proceeds through dependency/smoking persistence, continues with lung cancer development and ends with progression to disseminated disease or response to therapy and survival. The study allows the integration of data from multiple sources in the same subjects (risk factors, germline variation, genomic alterations in tumors, and clinical endpoints to tackle the disease etiology from different angles. Before beginning the study, we conducted a phone survey and pilot investigations to identify the best approach to ensure an acceptable participation in the study from cases and controls. Between 2002 and 2005, we enrolled 2101 incident primary lung cancer cases and 2120 population controls, with 86.6% and 72.4% participation rate, respectively, from a catchment area including 216 municipalities in the Lombardy region of Italy. Lung cancer cases were enrolled in 13 hospitals and population controls were randomly sampled from the area to match the cases by age, gender and residence. Detailed epidemiological information and biospecimens were collected from each participant, and clinical data and tissue specimens from the cases. Collection of follow-up data on treatment and survival is ongoing. Discussion EAGLE is a new population-based case-control study that explores the full spectrum of lung cancer etiology, from smoking addiction to lung cancer outcome, through

(SWASH-D for Worms: A pilot study investigating the differential impact of school- versus community-based integrated control programs for soil-transmitted helminths.

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Naomi E Clarke

2018-05-01

Full Text Available Soil-transmitted helminths (STH infect nearly 1.5 billion individuals globally, and contribute to poor physical and cognitive development in children. STH control programs typically consist of regular delivery of anthelminthic drugs, targeting school-aged children. Expanding STH control programs community-wide may improve STH control among school-aged children, and combining deworming with improvements to water, sanitation and hygiene (WASH may further reduce transmission. The (SWASH-D for Worms pilot study aims to compare the differential impact of integrated WASH and deworming programs when implemented at primary schools only versus when additionally implemented community-wide.A two-arm, non-randomized cluster intervention study was conducted. Six communities were identified by partner WASH agencies and enrolled in the study. All communities received a school-based WASH and deworming program, while three additionally received a community-based WASH and deworming program. STH infections were measured in school-aged children at baseline and six months after deworming. Over 90% of eligible children were recruited for the study, of whom 92.3% provided stool samples at baseline and 88.9% at follow-up. The school WASH intervention improved school sanitation, while the community WASH intervention reduced open defecation from 50.4% (95% CI 41.8-59.0 to 23.5% (95% CI 16.7-32.0. There was a trend towards reduced odds of N. americanus infection among children who received the community-wide intervention (OR 0.42, 95% CI 0.07-2.36, p = 0.32.This pilot study provides proof of principle for testing the hypothesis that community-wide STH control programs have a greater impact on STH infections among children than school-based programs, and supports the rationale for conducting a full-scale cluster randomized controlled trial. High recruitment and participation rates and successful implementation of school WASH programs demonstrate study feasibility and

Application of a pilot control strategy identification technique to a joint FAA/NASA ground-based simulation of head-up displays for CTOL aircraft

Science.gov (United States)

Jewell, W. F.

1982-01-01

A technique for measuring a pilot's control strategy was developed, evaluated, and applied to a joint FAA-NASA ground-based simulation of two competing concepts of head-up displays for use in conventional takeoff and landing aircraft. The technique, called the Non-Intrusive Pilot Identification Program (NIPIP), estimates the pilot's input-output describing function and combined pilot-vehicle performance parameters such as crossover frequency and phase margin by using a time domain model of the pilot and a least-squares identification algorithm. NIPIP functions in realtime and uses a sliding time window to maintain freshness in the data; thus time-varying characteristics in the pilot's control strategy can be measured.

Varenicline for opioid withdrawal in patients with chronic pain: a randomized, single-blinded, placebo controlled pilot trial.

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Hooten, W Michael; Warner, David O

2015-03-01

The objectives of this randomized, single-blinded, placebo-controlled pilot trial were to investigate the effects of varenicline on opioid withdrawal among chronic pain patients undergoing opioid detoxification in an interdisciplinary pain program and the feasibility of varenicline use in this population. Twenty-one patients were recruited (varenicline=10, placebo=11), and 7 patients in the varenicline and 11 in the placebo group completed the study. Opioid withdrawal was quantified using the Clinical Opiate Withdrawal Scale, and varenicline-related adverse effects were assessed. Opioid withdrawal scores tended to decrease over the course of opioid tapering in those receiving varenicline and increase in those receiving placebo. Varenicline was well-tolerated in this population, with no adverse drug effects (including nausea) observed and no effect on improvements in pain severity and depression. This randomized pilot study provides preliminary data for future trials of varenicline in opioid-dependent adults with chronic pain undergoing medically directed opioid detoxification. Copyright © 2014 Elsevier Ltd. All rights reserved.

Efficacy of botulinum toxin in treating myofascial pain in bruxers: a controlled placebo pilot study.

Science.gov (United States)

Guarda-Nardini, Luca; Manfredini, Daniele; Salamone, Milena; Salmaso, Luigi; Tonello, Stefano; Ferronato, Giuseppe

2008-04-01

The present investigation is a preliminary double-blind, controlled placebo, randomized clinical trial with a six month follow-up period. The study aimed to assess the efficacy of type A botulinum toxin (Botox, Allergan, Inc. Irvine, CA) to treat myofascial pain symptoms and to reduce muscle hyperactivity in bruxers. Twenty patients (ten males, ten females; age range 25-45) with a clinical diagnosis of bruxism and myofascial pain of the masticatory muscles were enrolled in a double-blind, controlled placebo, randomized clinical trial, with a treatment group (ten subjects treated with botulinum toxin injections- BTX-A) and a control group (ten subjects treated with saline placebo injections). A number of objective and subjective clinical parameters (pain at rest and during chewing; mastication efficiency; maximum nonassisted and assisted mouth opening, protrusive and laterotrusive movements; functional limitation during usual jaw movements; subjective efficacy of the treatment; tolerance of the treatment) were assessed at baseline time and at one week, one month, and six months follow-up appointments. Descriptive analysis showed that improvements in both objective (range of mandibular movements) and subjective (pain at rest; pain during chewing) clinical outcome variables were higher in the Botox treated group than in the placebo treated subjects. Patients treated with BTX-A had a higher subjective improvement in their perception of treatment efficacy than the placebo subjects. Differences were not significant in some cases due to the small sample size. Results from the present study supported the efficacy of BTX-A to reduce myofascial pain symptoms in bruxers, and provided pilot data which need to be confirmed by further research using larger samples.

Analysis of Pilot-Induced-Oscillation and Pilot Vehicle System Stability Using UAS Flight Experiments

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Tanmay K. Mandal

2016-11-01

Full Text Available This paper reports the results of a Pilot-Induced Oscillation (PIO and human pilot control characterization study performed using flight data collected with a Remotely Controlled (R/C unmanned research aircraft. The study was carried out on the longitudinal axis of the aircraft. Several existing Category 1 and Category 2 PIO criteria developed for manned aircraft are first surveyed and their effectiveness for predicting the PIO susceptibility for the R/C unmanned aircraft is evaluated using several flight experiments. It was found that the Bandwidth/Pitch rate overshoot and open loop onset point (OLOP criteria prediction results matched flight test observations. However, other criteria failed to provide accurate prediction results. To further characterize the human pilot control behavior during these experiments, a quasi-linear pilot model is used. The parameters of the pilot model estimated using data obtained from flight tests are then used to obtain information about the stability of the Pilot Vehicle System (PVS for Category 1 PIOs occurred during straight and level flights. The batch estimation technique used to estimate the parameters of the quasi-linear pilot model failed to completely capture the compatibility nature of the human pilot. The estimation results however provided valuable insights into the frequency characteristics of the human pilot commands. Additionally, stability analysis of the Category 2 PIOs for elevator actuator rate limiting is carried out using simulations and the results are compared with actual flight results.

A pilot's opinion - VTOL control design requirements for the instrument approach task.

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Patton, J. M., Jr.

1972-01-01

This paper presents pilot opinion supported by test data concerning flight control and display concepts and control system design requirements for VTOL aircraft in the instrument approach task. Material presented is drawn from research flights in the following aircraft: Dornier DO-31, Short SC-1, LTV XC-142A, and Boeing-Vertol CH-46. The control system concepts and mechanizations employed in the above aircraft are discussed, and the effect of control system augmentation is shown on performance. Operational procedures required in the instrument approach task are described, with comments on need for automation and combining of control functions.

Investigating the impact of the properties of pilot points on calibration of groundwater models: case study of a karst catchment in Rote Island, Indonesia

Science.gov (United States)

Klaas, Dua K. S. Y.; Imteaz, Monzur Alam

2017-09-01

A robust configuration of pilot points in the parameterisation step of a model is crucial to accurately obtain a satisfactory model performance. However, the recommendations provided by the majority of recent researchers on pilot-point use are considered somewhat impractical. In this study, a practical approach is proposed for using pilot-point properties (i.e. number, distance and distribution method) in the calibration step of a groundwater model. For the first time, the relative distance-area ratio ( d/ A) and head-zonation-based (HZB) method are introduced, to assign pilot points into the model domain by incorporating a user-friendly zone ratio. This study provides some insights into the trade-off between maximising and restricting the number of pilot points, and offers a relative basis for selecting the pilot-point properties and distribution method in the development of a physically based groundwater model. The grid-based (GB) method is found to perform comparably better than the HZB method in terms of model performance and computational time. When using the GB method, this study recommends a distance-area ratio of 0.05, a distance-x-grid length ratio ( d/ X grid) of 0.10, and a distance-y-grid length ratio ( d/ Y grid) of 0.20.

Preoperative home-based physical therapy versus usual care to improve functional health of frail older adults scheduled for elective total hip arthroplasty: A pilot randomized controlled trial

NARCIS (Netherlands)

Oosting, E.; Jans, M.P.; Dronkers, J.J.; Naber, R.H.; Dronkers-Landman, C.M.; Appelman-De Vries, S.M.; Meeteren, N.L. van

2012-01-01

Preoperative home-based physical therapy versus usual care to improve functional health of frail older adults scheduled for elective total hip arthroplasty: a pilot randomized controlled trial. Objective: To investigate the feasibility and preliminary effectiveness of a home-based intensive exercise

Laboratory, semi-pilot and room scale study of nitrite and molybdate mediated control of H(2)S emission from swine manure.

Science.gov (United States)

Moreno, Lyman; Predicala, Bernardo; Nemati, Mehdi

2010-04-01

The effects of manure age on emission of H(2)S and required level of nitrite or molybdate to control these emissions were investigated in the present work. Molybdate mediated control of H(2)S emission was also studied in semi-pilot scale open systems, and in specifically designed chambers which simulated swine production rooms. With fresh 1-, 3- and 6-month old manures average H(2)S concentration in the headspace gas of the closed systems were 4856+/-460, 3431+/-208, 1037+/-98 ppm and non-detectable, respectively. Moreover, the level of nitrite or molybdate required to control the emission of H(2)S decreased as manure age increased. In the semi-pilot scale open system and chambers, average H(2)S concentration at the surface of agitated fresh manure were 831+/-26 and 88.4+/-5.7 ppm, respectively. Furthermore, 0.1-0.25 mM molybdate was sufficient to control the emission of H(2)S. A cost study for an average size swine operation showed that the cost of treatment with molybdate was less than 1% of the overall production cost for each market hog. Copyright 2009 Elsevier Ltd. All rights reserved.

Investigation of KIF6 Trp719Arg in a case-control study of myocardial infarction: a Costa Rican population.

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Lance A Bare

2010-09-01

Full Text Available The 719Arg allele of KIF6 (rs20455 was associated with coronary events in Caucasian participants of five prospective studies. We investigated whether this KIF6 variant was associated with non-fatal myocardial infarction (MI in a case-control study of an admixed population from the Central Valley of Costa Rica. Genotypes of the KIF6 variant were determined for 4,134 men and women. Cases (1,987 had survived a first MI; controls (2,147 had no history of MI and were matched to cases by age, sex, and area of residence. We tested the association between the KIF6 719Arg allele and non-fatal MI by conditional logistic regression and adjusted for admixture of founder populations.Compared with the reference Trp/Trp homozygotes, KIF6 719Arg carriers were not at significantly higher risk for non-fatal MI in this study after adjustment for traditional risk factors or admixture (OR= 1.12; 95%CI, 0.98-1.28. Heterozygotes of the KIF6 Trp719Arg variant were at increased risk of non-fatal MI: the adjusted odds ratio was 1.16 (95% confidence interval, 1.01-1.34, but this association would not be significant after a multiple testing correction.We found that carriers of the KIF6 719Arg allele were not at increased risk of non-fatal MI in a case-control study of Costa Ricans living in the Central Valley of Costa Rica.

Hospital visitors as controls in case-control studies

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Gulnar Azevedo S Mendonça

2001-10-01

Full Text Available OBJECTIVE: Selecting controls is one of the most difficult tasks in the design of case-control studies. Hospital controls may be inadequate and random controls drawn from the base population may be unavailable. The aim was to assess the use of hospital visitors as controls in a case-control study on the association of organochlorinated compounds and other risk factors for breast cancer conducted in the main hospital of the "Instituto Nacional de Câncer" -- INCA (National Cancer Institute in Rio de Janeiro (Brazil. METHODS: The study included 177 incident cases and 377 controls recruited among female visitors. Three different models of control group composition were compared: Model 1, with all selected visitors; Model 2, excluding women visiting relatives with breast cancer; and Model 3, excluding all women visiting relatives with any type of cancer. Odds ratios (OR and 95% confidence intervals were calculated to test the associations. RESULTS: Age-adjusted OR for breast cancer associated with risk factors other than family history of cancer, except smoking and breast size, were similar in the three models. Regarding family history of all cancers, except for breast cancer, there was a decreased risk in Models 1 and 2, while in Model 3 there was an increased risk, but not statistically significant. Family history of breast cancer was a risk factor in Models 2 and 3, but no association was found in Model 1. In multivariate analysis a significant risk of breast cancer was found when there was a family history of breast cancer in Models 2 and 3 but not in Model 1. CONCLUSIONS: These results indicate that while investigating risk factors unrelated to family history of cancer, the use of hospital visitors as controls may be a valid and feasible alternative.

Cognitive Workload and Psychophysiological Parameters During Multitask Activity in Helicopter Pilots

OpenAIRE

Gaetan , Sophie; Dousset , Erick; Marqueste , Tanguy; Bringoux , Lionel; Bourdin , Christophe; Vercher , Jean-Louis; Besson , Patricia

2015-01-01

International audience; BACKGROUND: Helicopter pilots are involved in a complex multitask activity, implying overuse of cognitive resources, which may result in piloting task impairment or in decision-making failure. Studies usually investigate this phenomenon in well-controlled, poorly ecological situations by focusing on the correlation between physiological values and either cognitive workload or emotional state. This study aimed at jointly exploring workload induced by a realistic simulat...

[Epidemiological investigation on confirmed cases of schistosomiasis in Hubei Province].

Science.gov (United States)

Yan-Yan, Chen; Shun-Xiang, Cai; Guo, Li; Ying, Xiao; Xiao-Wei, Shan; Juan, Zhang; Jian-Bing, Liu

2016-05-10

To grasp the distribution and epidemiology of confirmed cases of schistosomiasis in Hubei Province, so as to provide the evidence for promoting the prevention and control work. The confirmed cases of schistosomiasis in Hubei Province from 2010 to 2014 were epidemiologically investigated, and the prevalence characteristics and main influencing factors were analyzed. A total of 10 102 confirmed cases from 2010 to 2014 were surveyed. There were 1 062 local infected patients, accounting for 10.51% and including 354 repeated infections and 17 newly infected. There were 290 foreigninfected patients, accounting for 2.87%, with 206 repeated infection cases and 84 newly infected. There were 8 750 historical patients, including 2 229 patients who leaked the former schistosomiasis investigations, accounting for 22.06%; 570 patients missed treatment, accounting for 5.64%; 3 640 patients were treated with non-standard therapy, accounting for 36.03%; 2 311 patients were treated with poor medication efficacy, accounting for 22.88%. The multivariate non-conditional Logistic regression, targeting at confirmed cases in 2014, showed that, for the leaking investigations, the potential risk factors included the age, educational level, and latrine renovation ( b ＞0, OR ＞1), the protective factors were the times of previous treatment, cattle feeding in villager team, and Oncomelania hupensis snails in surroundings ( b ＜0, OR ＜1); for the treatment-missing, the age, educational level, snails in the surroundings of residence were risk factors ( b ＜0, OR ＜1); for the substandard treatment, the risk factors included the occupation and snails in the surroundings of residence ( b ＞0, OR ＞1), and the educational level and snails in the own field were protective factors ( b ＜0, OR ＜1). The epidemiological investigation on the confirmed cases of schistosomiasis could grasp the epidemic factors so as to improve the management and carry out the scientific control.

EEG Neurofeedback for ADHD: Double-Blind Sham-Controlled Randomized Pilot Feasibility Trial

Science.gov (United States)

Arnold, L. Eugene; Lofthouse, Nicholas; Hersch, Sarah; Pan, Xueliang; Hurt, Elizabeth; Bates, Bethany; Kassouf, Kathleen; Moone, Stacey; Grantier, Cara

2013-01-01

Objective: Preparing for a definitive randomized clinical trial (RCT) of neurofeedback (NF) for ADHD, this pilot trial explored feasibility of a double-blind, sham-controlled design and adherence/palatability/relative effect of two versus three treatments/week. Method: Unmedicated 6- to 12-year-olds with "Diagnostic and Statistical Manual of…

Urine metabolomics in neonates with late-onset sepsis in a case-control study

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Sarafidis, Kosmas; Chatziioannou, Anastasia Chrysovalantou; Thomaidou, Agathi; Gika, Helen; Mikros, Emmanouel; Benaki, Dimitra; Diamanti, Elisavet; Agakidis, Charalampos; Raikos, Nikolaos; Drossou, Vasiliki; Theodoridis, Georgios

2017-04-01

Although late-onset sepsis (LOS) is a major cause of neonatal morbidity and mortality, biomarkers evaluated in LOS lack high diagnostic accuracy. In this prospective, case-control, pilot study, we aimed to determine the metabolic profile of neonates with LOS. Urine samples were collected at the day of initial LOS evaluation, the 3rd and 10th day, thereafter, from 16 septic neonates (9 confirmed and 7 possible LOS cases) and 16 non-septic ones (controls) at respective time points. Urine metabolic profiles were assessed using non-targeted nuclear magnetic resonance spectroscopy and targeted liquid chromatography-tandem mass spectrometry analysis. Multivariate statistical models with data from either analytical approach showed clear separation between the metabolic profiles of septic neonates (both possible and confirmed) and the controls. Metabolic changes appeared to be related to disease progression. Overall, neonates with confirmed or possible LOS exhibited comparable metabolic profiles indicating similar metabolic alternations upon the onset of clinical manifestations. This methodology therefore enabled the discrimination of neonates with LOS from non-septic individuals, providing potential for further research toward the discovery of LOS-related biomarkers.

A Pilot Randomized Controlled Trial of the ACCESS Program: A Group Intervention to Improve Social, Adaptive Functioning, Stress Coping, and Self-Determination Outcomes in Young Adults with Autism Spectrum Disorder

Science.gov (United States)

Oswald, Tasha M.; Winder-Patel, Breanna; Ruder, Steven; Xing, Guibo; Stahmer, Aubyn; Solomon, Marjorie

2018-01-01

The purpose of this pilot randomized controlled trial was to investigate the acceptability and efficacy of the Acquiring Career, Coping, Executive control, Social Skills (ACCESS) Program, a group intervention tailored for young adults with autism spectrum disorder (ASD) to enhance critical skills and beliefs that promote adult functioning,…

Dietary iron intake in the first 4 months of infancy and the development of type 1 diabetes: a pilot study

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Ashraf Ambika P

2010-09-01

Full Text Available Abstract Aims To investigate the impact of iron intake on the development of type 1 diabetes (T1DM. Methods Case-control study with self-administered questionnaire among families of children with T1DM who were less than 10 years old at the time of the survey and developed diabetes between age 1 and 6 years. Data on the types of infant feeding in the first 4 months of life was collected from parents of children with T1DM (n = 128 and controls (n = 67 Results The median (min, max total iron intake in the first 4 months of life was 1159 (50, 2399 mg in T1DM cases and 466 (50, 1224 mg among controls (P Conclusion In this pilot study, high iron intake in the first 4 months of infancy is associated with T1DM. Whether iron intake is causal or a marker of another risk factor warrants further investigation.

National Spill Control School. A pilot program in environmental training. Final report

Energy Technology Data Exchange (ETDEWEB)

Oberholtzer, G.R.; Acuff, J.T.

1980-01-01

Increased environmental awareness and the amended Federal Water Pollution Control Act of 1972 required an increased level of expertise by the American Public in the field of oil spill prevention and control. The National Spill Control School was created at Corpus Christi State University to help meet this need. Drawing on the talents of a nationwide sample of experts in this field, the project team created a unique management oriented course. A review of the origination and experiences of two years of classes of this pilot program is provided in this report.

Re-use of pilot data and interim analysis of pivotal data in MRMC studies: a simulation study

Science.gov (United States)

Chen, Weijie; Samuelson, Frank; Sahiner, Berkman; Petrick, Nicholas

2017-03-01

Novel medical imaging devices are often evaluated with multi-reader multi-case (MRMC) studies in which radiologists read images of patient cases for a specified clinical task (e.g., cancer detection). A pilot study is often used to measure the effect size and variance parameters that are necessary for sizing a pivotal study (including sizing readers, non-diseased and diseased cases). Due to the practical difficulty of collecting patient cases or recruiting clinical readers, some investigators attempt to include the pilot data as part of their pivotal study. In other situations, some investigators attempt to perform an interim analysis of their pivotal study data based upon which the sample sizes may be re-estimated. Re-use of the pilot data or interim analyses of the pivotal data may inflate the type I error of the pivotal study. In this work, we use the Roe and Metz model to simulate MRMC data under the null hypothesis (i.e., two devices have equal diagnostic performance) and investigate the type I error rate for several practical designs involving re-use of pilot data or interim analysis of pivotal data. Our preliminary simulation results indicate that, under the simulation conditions we investigated, the inflation of type I error is none or only marginal for some design strategies (e.g., re-use of patient data without re-using readers, and size re-estimation without using the effect-size estimated in the interim analysis). Upon further verifications, these are potentially useful design methods in that they may help make a study less burdensome and have a better chance to succeed without substantial loss of the statistical rigor.

Reducing TV watching during adult obesity treatment: two pilot randomized controlled trials.

Science.gov (United States)

Raynor, Hollie A; Steeves, Elizabeth Anderson; Bassett, David R; Thompson, Dixie L; Gorin, Amy A; Bond, Dale S

2013-12-01

The more time adults spend being sedentary, the greater the risk of obesity. The effect of reducing television (TV) watching, a prominent sedentary behavior, on weight loss has not been tested in an adult standard behavioral obesity intervention, and the mechanisms by which reducing TV watching influences energy balance behaviors are not well understood. Two, 8-week, pilot, randomized controlled trials were conducted examining the effect of a reduced TV watching prescription on energy balance behaviors and weight loss within an adult standard behavioral obesity intervention. In the first study, participants (n=24) were randomized into one of two conditions: (a) reduce energy intake and increase moderate to vigorous physical activity (MVPA) (INCREASE PA); or (b) reduce energy intake and decrease TV watching (DECREASE TV). As findings from the first pilot study did not show an increase in MVPA in the DECREASE TV group, the second study was designed to examine the effect of adding a reduced TV prescription to a standard intervention to optimize outcomes. In Pilot Study 2, participants (n=28) were randomized to INCREASE PA or to INCREASE PA+DECREASE TV. Outcomes included objectively measured TV watching and MVPA, self-reported light physical activity (LPA-Pilot Study 2 only), self-reported dietary intake while watching TV, and weight. Conditions with TV watching prescriptions significantly reduced TV watching. Both studies showed medium to large effect sizes for conditions with TV watching prescriptions to show greater reductions in dietary intake while watching TV. Pilot Study 1 found a trend for an increase in MVPA in INCREASE PA and Pilot Study 2 found significant increases in MVPA in both conditions. Pilot Study 2 found a significant increase in LPA in the INCREASE PA+DECREASE TV. Results indicate adding a TV watching prescription to a standard obesity intervention did not enhance increases in MVPA, but may assist with reducing dietary intake while TV watching and

A piloted evaluation of an oblique-wing research aircraft motion simulation with decoupling control laws

Science.gov (United States)

Kempel, Robert W.; Mcneill, Walter E.; Gilyard, Glenn B.; Maine, Trindel A.

1988-01-01

The NASA Ames Research Center developed an oblique-wing research plane from NASA's digital fly-by-wire airplane. Oblique-wing airplanes show large cross-coupling in control and dynamic behavior which is not present on conventional symmetric airplanes and must be compensated for to obtain acceptable handling qualities. The large vertical motion simulator at NASA Ames-Moffett was used in the piloted evaluation of a proposed flight control system designed to provide decoupled handling qualities. Five discrete flight conditions were evaluated ranging from low altitude subsonic Mach numbers to moderate altitude supersonic Mach numbers. The flight control system was effective in generally decoupling the airplane. However, all participating pilots objected to the high levels of lateral acceleration encountered in pitch maneuvers. In addition, the pilots were more critical of left turns (in the direction of the trailing wingtip when skewed) than they were of right turns due to the tendency to be rolled into the left turns and out of the right turns. Asymmetric side force as a function of angle of attack was the primary cause of lateral acceleration in pitch. Along with the lateral acceleration in pitch, variation of rolling and yawing moments as functions of angle of attack caused the tendency to roll into left turns and out of right turns.

Pilot Domain Task Experience in Night Fatal Helicopter Emergency Medical Service Accidents.

Science.gov (United States)

Aherne, Bryan B; Zhang, Chrystal; Newman, David G

2016-06-01

In the United States, accident and fatality rates in helicopter emergency medical service (HEMS) operations increase significantly under nighttime environmentally hazardous operational conditions. Other studies have found pilots' total flight hours unrelated to HEMS accident outcomes. Many factors affect pilots' decision making, including their experience. This study seeks to investigate whether pilot domain task experience (DTE) in HEMS plays a role against likelihood of accidents at night when hazardous operational conditions are entered. There were 32 flights with single pilot nighttime fatal HEMS accidents between 1995 and 2013 with findings of controlled flight into terrain (CFIT) and loss of control (LCTRL) due to spatial disorientation (SD) identified. The HEMS DTE of the pilots were compared with industry survey data. Of the pilots, 56% had ≤2 yr of HEMS experience and 9% had >10 yr of HEMS experience. There were 21 (66%) accidents that occurred in non-visual flight rules (VFR) conditions despite all flights being required to be conducted under VFR. There was a statistically significant increase in accident rates in pilots with pilots with >10 yr HEMS DTE. HEMS DTE plays a preventive role against the likelihood of a night operational accident. Pilots with limited HEMS DTE are more likely to make a poor assessment of hazardous conditions at night, and this will place HEMS flight crew at high risk in the VFR night domain.

Improving discharge care: the potential of a new organisational intervention to improve discharge after hospitalisation for acute stroke, a controlled before–after pilot study

OpenAIRE

Cadilhac, Dominique A; Andrew, Nadine E; Stroil Salama, Enna; Hill, Kelvin; Middleton, Sandy; Horton, Eleanor; Meade, Ian; Kuhle, Sarah; Nelson, Mark R; Grimley, Rohan

2017-01-01

Objective Provision of a discharge care plan and prevention therapies is often suboptimal. Our objective was to design and pilot test an interdisciplinary, organisational intervention to improve discharge care using stroke as the case study using a mixed-methods, controlled before–after observational study design. Setting Acute care public hospitals in Queensland, Australia (n=15). The 15 hospitals were ranked against a benchmark based on a composite outcome of three discharge care processes....

Effects of Video Weather Training Products, Web-Based Preflight Weather Briefing, and Local Versus Non-Local Pilots on General Aviation Pilot Weather Knowledge and Flight Behavior. Phase 2

Science.gov (United States)

2010-03-01

homa pilots are representative of u.S. pilots in general. Presumably, they are similar but, so far, this has not been directly investigated. Since...1 Training Product 2 Control Combined group n Age FH % IR n Age FH % IR n Age FH % IR N Age FH % IR Phase 1 16 39 280 53 16 38 235.5 47 18 42 262.5 50 50

Group Singing as a Therapy during Diabetes Training--A Randomized Controlled Pilot Study.

Science.gov (United States)

Groener, J B; Neus, I; Kopf, S; Hartmann, M; Schanz, J; Kliemank, E; Wetekam, B; Kihm, L; Fleming, T; Herzog, W; Nawroth, P P

2015-11-01

Comprehensive diabetes treatment has been shown to reduce quality of life in diabetic patients. However, there is evidence to suggest that group singing can have positive effects on quality of life in various clinical settings. In this randomized controlled pilot study, the effect of singing as a therapy to reduce stress and improve quality of life was investigated in insulin-dependent diabetic patients, undergoing a lifestyle intervention program. Patients from the singing group felt less discontented following treatment. This effect, however, was lost after 3 months. No effect on serum cortisol and plasma adrenocorticotropic hormone (ACTH) levels could be seen when comparing the singing group with the control group, although reduced levels of ACTH and cortisol 3 days after treatment could be found and were still present after 3 months within the group of patients who undertook singing as a therapy. Singing led to an increase in bodyweight, which interestingly had no effect on glucose control or methylglyoxal levels. Therefore, singing during a lifestyle intervention program for insulin-dependent diabetic patients had a short lasting and weak effect on patients' mood without affecting glucose control, but no significant effect on stress related hormones. © Georg Thieme Verlag KG Stuttgart · New York.

Doping control container for urine stabilization: a pilot study.

Science.gov (United States)

Tsivou, Maria; Giannadaki, Evangelia; Hooghe, Fiona; Roels, Kris; Van Gansbeke, Wim; Garribba, Flaminia; Lyris, Emmanouil; Deventer, Koen; Mazzarino, Monica; Donati, Francesco; Georgakopoulos, Dimitrios G; Van Eenoo, Peter; Georgakopoulos, Costas G; de la Torre, Xavier; Botrè, Francesco

2017-05-01

Urine collection containers used in the doping control collection procedure do not provide a protective environment for urine, against degradation by microorganisms and proteolytic enzymes. An in-house chemical stabilization mixture was developed to tackle urine degradation problems encountered in human sport samples, in cases of microbial contamination or proteolytic activity. The mixture consists of antimicrobial substances and protease inhibitors for the simultaneous inactivation of a wide range of proteolytic enzymes. It has already been tested in lab-scale, as part of World Anti-Doping Agency's (WADA) funded research project, in terms of efficiency against microbial and proteolytic activity. The present work, funded also by WADA, is a follow-up study on the improvement of chemical stabilization mixture composition, application mode and limitation of interferences, using pilot urine collection containers, spray-coated in their internal surface with the chemical stabilization mixture. Urine in plastic stabilized collection containers have been gone through various incubation cycles to test for stabilization efficiency and analytical matrix interferences by three WADA accredited Laboratories (Athens, Ghent, and Rome). The spray-coated chemical stabilization mixture was tested against microorganism elimination and steroid glucuronide degradation, as well as enzymatic breakdown of proteins, such as intact hCG, recombinant erythropoietin and small peptides (GHRPs, ipamorelin), induced by proteolytic enzymes. Potential analytical interferences, observed in the presence of spray-coated chemical stabilization mixture, were recorded using routine screening procedures. The results of the current study support the application of the spray-coated plastic urine container, in the doping control collection procedure. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

The poststall nonlinear dynamics and control of an F-18: A preliminary investigation

Science.gov (United States)

Patten, William N.

1988-01-01

The successful high angle of attack (HAOA) operation of fighter aircraft will necessarily require the introduction of a new onboard control methodology that address the nonlinearity of the system when flown at the stall/poststall limits of the craft's flight envelope. As a precursor to this task, a researcher endeavored to familarize himself with the dynamics of one specific aircraft, the F-18, when it is flown at HAOA. This was accomplished by conducting a number of real time flight sorties using the NASA-Langley Research Center's F-18 simulator, which was operated with a pilot in the loop. In addition to developing a first hand familarity with the aircraft's dynamic characteristic at HAOA, work was also performed to identify the input/output operational footprint of the F-18's control surfaces. This investigator proposes to employ the nonlinear models of the plant identified this summer in a subsequent research effort that will make it possible to fly the F-18 effectively at poststall angles of attack. The controller design used there will rely on a new technique proposed by this investigator that provides for the automatic generation of online optimal control solutions for nonlinear dynamic systems.

Comparison of Postural Responses to Galvanic Vestibular Stimulation between Pilots and the General Populace

Directory of Open Access Journals (Sweden)

Yang Yang

2015-01-01

Full Text Available Galvanic vestibular stimulation (GVS can be used to study the body’s response to vestibular stimuli. This study aimed to investigate whether postural responses to GVS were different between pilots and the general populace. Bilateral bipolar GVS was applied with a constant-current profile to 12 pilots and 12 control subjects via two electrodes placed over the mastoid processes. Both GVS threshold and the center of pressure’s trajectory (COP’s trajectory were measured. Position variability of COP during spontaneous body sway and peak displacement of COP during GVS-induced body sway were calculated in the medial-lateral direction. Spontaneous body sway was slight for all subjects, and there was no significant difference in the value of COP position variability between the pilots and controls. Both the GVS threshold and magnitude of GVS-induced body deviation were similar for different GVS polarities. GVS thresholds were similar between the two groups, but the magnitude of GVS-induced body deviation in the controls was significantly larger than that in the pilots. The pilots showed less GVS-induced body deviation, meaning that pilots may have a stronger ability to suppress vestibular illusions.

Prediction of pilot induced oscillations

Directory of Open Access Journals (Sweden)

Valentin PANĂ

2011-03-01

Full Text Available An important problem in the design of flight-control systems for aircraft under pilotedcontrol is the determination of handling qualities and pilot-induced oscillations (PIO tendencieswhen significant nonlinearities exist in the vehicle description. The paper presents a method to detectpossible pilot-induced oscillations of Category II (with rate and position limiting, a phenomenonusually due to a misadaptation between the pilot and the aircraft response during some tasks in whichtight closed loop control of the aircraft is required from the pilot. For the analysis of Pilot in the LoopOscillations an approach, based on robust stability analysis of a system subject to uncertainparameters, is proposed. In this analysis the nonlinear elements are substituted by linear uncertainparameters. This approach assumes that PIO are characterized by a limit cycle behavior.

Effects of Combining a Brief Cognitive Intervention with Transcranial Direct Current Stimulation on Pain Tolerance: A Randomized Controlled Pilot Study.

Science.gov (United States)

Powers, Abigail; Madan, Alok; Hilbert, Megan; Reeves, Scott T; George, Mark; Nash, Michael R; Borckardt, Jeffrey J

2018-04-01

Cognitive behavioral therapy has been shown to be effective for treating chronic pain, and a growing literature shows the potential analgesic effects of minimally invasive brain stimulation. However, few studies have systematically investigated the potential benefits associated with combining approaches. The goal of this pilot laboratory study was to investigate the combination of a brief cognitive restructuring intervention and transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex in affecting pain tolerance. Randomized, double-blind, placebo-controlled laboratory pilot. Medical University of South Carolina. A total of 79 healthy adult volunteers. Subjects were randomized into one of six groups: 1) anodal tDCS plus a brief cognitive intervention (BCI); 2) anodal tDCS plus pain education; 3) cathodal tDCS plus BCI; 4) cathodal tDCS plus pain education; 5) sham tDCS plus BCI; and 6) sham tDCS plus pain education. Participants underwent thermal pain tolerance testing pre- and postintervention using the Method of Limits. A significant main effect for time (pre-post intervention) was found, as well as for baseline thermal pain tolerance (covariate) in the model. A significant time × group interaction effect was found on thermal pain tolerance. Each of the five groups that received at least one active intervention outperformed the group receiving sham tDCS and pain education only (i.e., control group), with the exception of the anodal tDCS + education-only group. Cathodal tDCS combined with the BCI produced the largest analgesic effect. Combining cathodal tDCS with BCI yielded the largest analgesic effect of all the conditions tested. Future research might find stronger interactive effects of combined tDCS and a cognitive intervention with larger doses of each intervention. Because this controlled laboratory pilot employed an acute pain analogue and the cognitive intervention did not authentically represent cognitive behavioral

Physical activity and lung cancer among non-smokers: A pilot molecular epidemiologic study within EPIC

Science.gov (United States)

RUNDLE, ANDREW; RICHIE, JOHN; STEINDORF, KAREN; PELUSO, MARCO; OVERVAD, KIM; RAASCHOU-NIELSEN, OLE; CLAVEL-CHAPELON, FRANCOISE; LINSEISEN, JACOB P.; BOEING, HEINER; TRICHOPOULOU, ANTONIA; PALLI, DOMENICO; KROGH, VITTORIO; TUMINO, ROSARIO; PANICO, SALVATORE; BUENO-DE-MESQUITA, HENDRIK B.; PEETERS, PETRA H.; LUND, EILIV; GONZALEZ, CARLOS A.; MARTINEZ, CARMEN; DORRONSORO, MIREN; BARRICARTE, AURELIO; TORMO, M. JOSE; QUIROS, JOSÈ R.; AGUDO, ANTONIO; BERGLUND, GORAN; JARVHOLM, BENGT; BINGHAM, SHEILA; KEY, TIMOTHY J.; GORMALLY, EMMANUELLE; SARACCI, RODOLFO; KAAKS, RUDOLF; RIBOLI, ELIO; VINEIS, PAOLO

2013-01-01

The association between physical activity, potential intermediate biomarkers and lung cancer risk was investigated in a study of 230 cases and 648 controls nested within the European Prospective Investigation of Cancer and Nutrition. Data on white blood cell aromatic-DNA adducts by 32P-postlabeling and glutathione (GSH) in red blood cells were available from a subset of cases and controls. Compared to the first quartile, the fourth quartile of recreational physical activity was associated with lower lung cancer risk [odds ratio=0.56 (0.35–0.90)], higher GSH levels [+1.87 micro mole GSH/gram haemoglobin, p=0.04] but not with the presence of high levels of adducts [odds ratio=1.05 (0.38–2.86)]. Despite being associated with recreational physical activity, in these small scale pilot analyses GSH levels were not associated with lung cancer risk, [odds ratio=0.95 (0.84 – 1.07) per unit increase in glutathione levels]. Household and occupational activity was not associated with lung cancer risk or biomarker levels. PMID:20050820

A pilot study to examine maturation of body temperature control in preterm infants.

Science.gov (United States)

Knobel, Robin B; Levy, Janet; Katz, Laurence; Guenther, Bob; Holditch-Davis, Diane

2013-01-01

To test instrumentation and develop analytic models to use in a larger study to examine developmental trajectories of body temperature and peripheral perfusion from birth in extremely low-birth-weight (EBLW) infants. A case study design. The study took place in a Level 4 neonatal intensive care unit (NICU) in North Carolina. Four ELBW infants, fewer than 29 weeks gestational age at birth. Physiologic data were measured every minute for the first 5 days of life: peripheral perfusion using perfusion index by Masimo and body temperature using thermistors. Body temperature was also measured using infrared thermal imaging. Stimulation and care events were recorded over the first 5 days using video which was coded with Noldus Observer software. Novel analytical models using the state space approach to time-series analysis were developed to explore maturation of neural control over central and peripheral body temperature. Results from this pilot study confirmed the feasibility of using multiple instruments to measure temperature and perfusion in ELBW infants. This approach added rich data to our case study design and set a clinical context with which to interpret longitudinal physiological data. © 2013 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses.

Piloted Evaluation of Modernized Limited Authority Control Laws in the NASA-Ames Vertical Motion Simulator (VMS)

Science.gov (United States)

Sahasrabudhe, Vineet; Melkers, Edgar; Faynberg, Alexander; Blanken, Chris L.

2003-01-01

The UH-60 BLACK HAWK was designed in the 1970s, when the US Army primarily operated during the day in good visual conditions. Subsequently, the introduction of night-vision goggles increased the BLACK HAWK'S mission effectiveness, but the accident rate also increased. The increased accident rate is strongly tied to increased pilot workload as a result of a degradation in visual cues. Over twenty years of research in helicopter flight control and handling qualities has shown that these degraded handling qualities can be recovered by modifying the response type of the helicopter in low speed flight. Sikorsky Aircraft Corporation initiated a project under the National Rotorcraft Technology Center (NRTC) to develop modern flight control laws while utilizing the existing partial authority Stability Augmentation System (SAS) of the BLACK HAWK. This effort resulted in a set of Modernized Control Laws (MCLAWS) that incorporate rate command and attitude command response types. Sikorsky and the US Army Aeroflightdynamics Directorate (AFDD) conducted a piloted simulation on the NASA-Ames Vertical h4otion Simulator, to assess potential handling qualities and to reduce the risk of subsequent implementation and flight test of these modern control laws on AFDD's EH-60L helicopter. The simulation showed that Attitude Command Attitude Hold control laws in pitch and roll improve handling qualities in the low speed flight regime. These improvements are consistent across a range of mission task elements and for both good and degraded visual environments. The MCLAWS perform better than the baseline UH-60A control laws in the presence of wind and turbulence. Finally, while the improved handling qualities in the pitch and roll axis allow the pilot to pay more attention to the vertical axis and hence altitude performance also improves, it is clear from pilot comments and altitude excursions that the addition of an Altitude Hold function would further reduce workload and improve overall

INfluence of Successful Periodontal Intervention in REnal Disease (INSPIRED): study protocol for a randomised controlled pilot clinical trial.

Science.gov (United States)

Sharma, Praveen; Cockwell, Paul; Dietrich, Thomas; Ferro, Charles; Ives, Natalie; Chapple, Iain L C

2017-11-13

trial later, data on cardio-renal function, periodontal health and patient-reported outcomes will be collected at each time point. This pilot randomised controlled trial will investigate the viability of undertaking a larger-scale study investigating the effect of treating periodontitis and maintaining periodontal health on cardio-renal outcomes in patients with CKD. National Institute of Health Research (NIHR) Clinical Research Network (UKCRN ID: 18458), ID: ISRCTN10227738 . Registered retrospectively to both registers on 23 April 2015.

Evaluation of the 'Alternative Commissioning of Experts Pilot'\\ud \\ud Pilot’

OpenAIRE

Tucker, Jason; Moorhead, Richard Lewis; Doughty, Julie

2011-01-01

This project evaluated a pilot engaging six multi-disciplinary teams commissioned by the Legal Services Commission to provide expert witness services in proceedings under section 31 Children Act 1989.\\ud Pilot teams did not attract large numbers of cases, with two teams undertaking no cases under the pilot. Lack of awareness of the pilot, the duration of the pilot and concerns (particularly amongst lawyers) about the implications of team-based expert witness services all inhibited take-up. Ju...

A forensic perspective of the AFL investigation into peptides: an antidoping investigation case study.

Science.gov (United States)

Harcourt, Peter Rex; Marclay, Francois; Clothier, Brett

2014-05-01

The World Anti-Doping Agency (WADA) is introducing enhancements to doping investigations in its 2015 Code, which include improved sharing of information between antidoping organisations (including sporting bodies) and enhanced accountability of athlete support staff. These additions will improve the control of links between sports doping and organised crime. In February 2013 the Australian Crime Commission released a report that linked several professional sporting codes, professional athletes with links to organised crime, performance enhancing drugs and illicit substances. Following this report the Australian Football League (AFL) partnered the Australian national antidoping organisation to investigate peptide use in Australian football. This review compared the model proposed by Marclay, a hypothetical model for anti-doping investigations that proposed a forensic intelligence and analysis approach, to use the forensic capabilities of the AFL investigation to test the model's relevance to an actual case. The investigation uncovered the use of peptides used to enhance athlete performance. The AFL investigation found a high risk of doping where athlete support staff existed in teams with weak corporate governance controls. A further finding included the need for the investigation to provide a timely response in professional team sports that were sensitive to the competition timing. In the case of the AFL the team was sanctioned prior to the finals as an interim outcome for allowing the risk of use of performance-enhancing substances. Doping violation charges are still being considered. Antidoping strategies should include the investigation of corporate officers in team doping circumstances, the mandatory recording of all athlete substance use during competition and training phases, the wider sharing of forensic intelligence with non-sporting bodies particularly law enforcement and collaboration between antidoping and sporting organisations in doping investigations

Preparing Pilots for Takeoff

Science.gov (United States)

Ravage, Barbara

2012-01-01

Why would schools consider partnering with a vendor to operate a pilot? Why not just wait until the final product is released? For starters, pilots provide schools with a golden opportunity to get an early look at the software, take it for a test flight, and ask for changes tailored to their operating environment and business needs. In some cases,…

Retaining U.S. Air Force Pilots When the Civilian Demand for Pilots Is Growing

Science.gov (United States)

2016-01-01

compensation, so a 1-percent increase in basic pay is like a 0.6-percent increase in total pay, other things being equal . If so, the retention change...at other major airlines.3 The collective bargaining agreement called for American/US Airways pilots to reach pay parity with Delta and United pilots...non-veterans in non- pilot occupations after controlling for age, education, and gender . But the results show that pilots who are veterans earn 10 to

Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses.

Science.gov (United States)

Keogh, Ruth H; Mangtani, Punam; Rodrigues, Laura; Nguipdop Djomo, Patrick

2016-01-05

Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

Case-control vaccine effectiveness studies: Preparation, design, and enrollment of cases and controls.

Science.gov (United States)

Verani, Jennifer R; Baqui, Abdullah H; Broome, Claire V; Cherian, Thomas; Cohen, Cheryl; Farrar, Jennifer L; Feikin, Daniel R; Groome, Michelle J; Hajjeh, Rana A; Johnson, Hope L; Madhi, Shabir A; Mulholland, Kim; O'Brien, Katherine L; Parashar, Umesh D; Patel, Manish M; Rodrigues, Laura C; Santosham, Mathuram; Scott, J Anthony; Smith, Peter G; Sommerfelt, Halvor; Tate, Jacqueline E; Victor, J Chris; Whitney, Cynthia G; Zaidi, Anita K; Zell, Elizabeth R

2017-06-05

Case-control studies are commonly used to evaluate effectiveness of licensed vaccines after deployment in public health programs. Such studies can provide policy-relevant data on vaccine performance under 'real world' conditions, contributing to the evidence base to support and sustain introduction of new vaccines. However, case-control studies do not measure the impact of vaccine introduction on disease at a population level, and are subject to bias and confounding, which may lead to inaccurate results that can misinform policy decisions. In 2012, a group of experts met to review recent experience with case-control studies evaluating the effectiveness of several vaccines; here we summarize the recommendations of that group regarding best practices for planning, design and enrollment of cases and controls. Rigorous planning and preparation should focus on understanding the study context including healthcare-seeking and vaccination practices. Case-control vaccine effectiveness studies are best carried out soon after vaccine introduction because high coverage creates strong potential for confounding. Endpoints specific to the vaccine target are preferable to non-specific clinical syndromes since the proportion of non-specific outcomes preventable through vaccination may vary over time and place, leading to potentially confusing results. Controls should be representative of the source population from which cases arise, and are generally recruited from the community or health facilities where cases are enrolled. Matching of controls to cases for potential confounding factors is commonly used, although should be reserved for a limited number of key variables believed to be linked to both vaccination and disease. Case-control vaccine effectiveness studies can provide information useful to guide policy decisions and vaccine development, however rigorous preparation and design is essential. Published by Elsevier Ltd.

46 CFR 15.812 - Pilots.

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Pilots. 15.812 Section 15.812 Shipping COAST GUARD....812 Pilots. (a) Except as specified in paragraph (f) of this section, the following vessels, not... direction and control of an individual qualified to serve as pilot under paragraph (b) or (c) of this...

14 CFR 29.1329 - Automatic pilot system.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Automatic pilot system. 29.1329 Section 29... pilot system. (a) Each automatic pilot system must be designed so that the automatic pilot can— (1) Be sufficiently overpowered by one pilot to allow control of the rotorcraft; and (2) Be readily and positively...

14 CFR 27.1329 - Automatic pilot system.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Automatic pilot system. 27.1329 Section 27... pilot system. (a) Each automatic pilot system must be designed so that the automatic pilot can— (1) Be sufficiently overpowered by one pilot to allow control of the rotorcraft; and (2) Be readily and positively...

Case-Control Studies - An Efficient Observational Study Design

NARCIS (Netherlands)

van Stralen, Karlijn J.; Dekker, Friedo W.; Zoccali, Carmine; Jager, Kitty J.

2010-01-01

Case-control studies are an efficient research method for investigating risk factors of a disease. The method involves the comparison of the odds of exposure in a patient group with that of the odds of exposure in a control group. As only a minority of the population is included in the study, less

Case-control vaccine effectiveness studies: Data collection, analysis and reporting results.

Science.gov (United States)

Verani, Jennifer R; Baqui, Abdullah H; Broome, Claire V; Cherian, Thomas; Cohen, Cheryl; Farrar, Jennifer L; Feikin, Daniel R; Groome, Michelle J; Hajjeh, Rana A; Johnson, Hope L; Madhi, Shabir A; Mulholland, Kim; O'Brien, Katherine L; Parashar, Umesh D; Patel, Manish M; Rodrigues, Laura C; Santosham, Mathuram; Scott, J Anthony; Smith, Peter G; Sommerfelt, Halvor; Tate, Jacqueline E; Victor, J Chris; Whitney, Cynthia G; Zaidi, Anita K; Zell, Elizabeth R

2017-06-05

The case-control methodology is frequently used to evaluate vaccine effectiveness post-licensure. The results of such studies provide important insight into the level of protection afforded by vaccines in a 'real world' context, and are commonly used to guide vaccine policy decisions. However, the potential for bias and confounding are important limitations to this method, and the results of a poorly conducted or incorrectly interpreted case-control study can mislead policies. In 2012, a group of experts met to review recent experience with case-control studies evaluating vaccine effectiveness; we summarize the recommendations of that group regarding best practices for data collection, analysis, and presentation of the results of case-control vaccine effectiveness studies. Vaccination status is the primary exposure of interest, but can be challenging to assess accurately and with minimal bias. Investigators should understand factors associated with vaccination as well as the availability of documented vaccination status in the study context; case-control studies may not be a valid method for evaluating vaccine effectiveness in settings where many children lack a documented immunization history. To avoid bias, it is essential to use the same methods and effort gathering vaccination data from cases and controls. Variables that may confound the association between illness and vaccination are also important to capture as completely as possible, and where relevant, adjust for in the analysis according to the analytic plan. In presenting results from case-control vaccine effectiveness studies, investigators should describe enrollment among eligible cases and controls as well as the proportion with no documented vaccine history. Emphasis should be placed on confidence intervals, rather than point estimates, of vaccine effectiveness. Case-control studies are a useful approach for evaluating vaccine effectiveness; however careful attention must be paid to the collection

Pilot Project Technology Business Case: Mobile Work Packages

Energy Technology Data Exchange (ETDEWEB)

Thomas, Ken [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lawrie, Sean [ScottMadden, Inc., Raleigh, NC (United States); Niedermuller, Josef [ScottMadden, Inc., Raleigh, NC (United States)

2015-05-01

Performance advantages of the new pilot project technologies are widely acknowledged, but it has proven difficult for utilities to derive business cases for justifying investment in these new capabilities. Lack of a business case is often cited by utilities as a barrier to pursuing wide-scale application of digital technologies to nuclear plant work activities. The decision to move forward with funding usually hinges on demonstrating actual cost reductions that can be credited to budgets and thereby truly reduce O&M or capital costs. Technology enhancements, while enhancing work methods and making work more efficient, often fail to eliminate workload such that it changes overall staffing and material cost requirements. It is critical to demonstrate cost reductions or impacts on non-cost performance objectives in order for the business case to justify investment by nuclear operators. The Business Case Methodology (BCM) was developed in September of 2015 to frame the benefit side of II&C technologies to address the “benefit” side of the analysis—as opposed to the cost side—and how the organization evaluates discretionary projects (net present value (NPV), accounting effects of taxes, discount rates, etc.). The cost and analysis side is not particularly difficult for the organization and can usually be determined with a fair amount of precision (not withstanding implementation project cost overruns). It is in determining the “benefits” side of the analysis that utilities have more difficulty in technology projects and that is the focus of this methodology. The methodology is presented in the context of the entire process, but the tool provided is limited to determining the organizational benefits only. This report describes a the use of the BCM in building a business case for mobile work packages, which includes computer-based procedures and other automated elements of a work package. Key to those impacts will be identifying where the savings are �

Recruitment to Online Therapies for Depression: Pilot Cluster Randomized Controlled Trial

OpenAIRE

Jones, Ray B; Goldsmith, Lesley; Hewson, Paul; Williams, Christopher J

2013-01-01

Background Raising awareness of online cognitive behavioral therapy (CBT) could benefit many people with depression, but we do not know how purchasing online advertising compares to placing free links from relevant local websites in increasing uptake. Objective To pilot a cluster randomized controlled trial (RCT) comparing purchase of Google AdWords with placing free website links in raising awareness of online CBT resources for depression in order to better understand research design issues....

Personality Factors Affecting Pilot Combat Performance: A Preliminary Investigation

National Research Council Canada - National Science Library

Siem, Frederick M; Murray, Michael W

1997-01-01

.... The present research was designed to examine the relationship between personality and combat performance using the "Big Five" model of personality and a multicomponent model of pilot combat performance...

In silico vs. Over the Clouds: On-the-Fly Mental State Estimation of Aircraft Pilots, Using a Functional Near Infrared Spectroscopy Based Passive-BCI.

Science.gov (United States)

Gateau, Thibault; Ayaz, Hasan; Dehais, Frédéric

2018-01-01

There is growing interest for implementing tools to monitor cognitive performance in naturalistic work and everyday life settings. The emerging field of research, known as neuroergonomics, promotes the use of wearable and portable brain monitoring sensors such as functional near infrared spectroscopy (fNIRS) to investigate cortical activity in a variety of human tasks out of the laboratory. The objective of this study was to implement an on-line passive fNIRS-based brain computer interface to discriminate two levels of working memory load during highly ecological aircraft piloting tasks. Twenty eight recruited pilots were equally split into two groups (flight simulator vs. real aircraft). In both cases, identical approaches and experimental stimuli were used (serial memorization task, consisting in repeating series of pre-recorded air traffic control instructions, easy vs. hard). The results show pilots in the real flight condition committed more errors and had higher anterior prefrontal cortex activation than pilots in the simulator, when completing cognitively demanding tasks. Nevertheless, evaluation of single trial working memory load classification showed high accuracy (>76%) across both experimental conditions. The contributions here are two-fold. First, we demonstrate the feasibility of passively monitoring cognitive load in a realistic and complex situation (live piloting of an aircraft). In addition, the differences in performance and brain activity between the two experimental conditions underscore the need for ecologically-valid investigations.

Gender differences in navigational memory: pilots vs. nonpilots.

Science.gov (United States)

Verde, Paola; Piccardi, Laura; Bianchini, Filippo; Guariglia, Cecilia; Carrozzo, Paolo; Morgagni, Fabio; Boccia, Maddalena; Di Fiore, Giacomo; Tomao, Enrico

2015-02-01

The coding of space as near and far is not only determined by arm-reaching distance, but is also dependent on how the brain represents the extension of the body space. Recent reports suggest that the dissociation between reaching and navigational space is not limited to perception and action but also involves memory systems. It has been reported that gender differences emerged only in adverse learning conditions that required strong spatial ability. In this study we investigated navigational versus reaching memory in air force pilots and a control group without flight experience. We took into account temporal duration (working memory and long-term memory) and focused on working memory, which is considered critical in the gender differences literature. We found no gender effects or flight hour effects in pilots but observed gender effects in working memory (but not in learning and delayed recall) in the nonpilot population (Women's mean = 5.33; SD= 0.90; Men's mean = 5.54; SD= 0.90). We also observed a difference between pilots and nonpilots in the maintenance of on-line reaching information: pilots (mean = 5.85; SD=0.76) were more efficient than nonpilots (mean = 5.21; SD=0.83) and managed this type of information similarly to that concerning navigational space. In the navigational learning phase they also showed better navigational memory (mean = 137.83; SD=5.81) than nonpilots (mean = 126.96; SD=15.81) and were significantly more proficient than the latter group. There is no gender difference in a population of pilots in terms of navigational abilities, while it emerges in a control group without flight experience. We found also that pilots performed better than nonpilots. This study suggests that once selected, male and female pilots do not differ from each other in visuo-spatial abilities and spatial navigation.

Pilot Investigation of a Virtual Gastric Band Hypnotherapy Intervention.

Science.gov (United States)

Greetham, Stephanie; Goodwin, Sarah; Wells, Liz; Whitham, Claire; Jones, Huw; Rigby, Alan; Sathyapalan, Thozhukat; Reid, Marie; Atkin, Stephen

2016-01-01

This 24-week-long pilot investigation of 30 men and women with a BMI > 27 kg/m(2) aimed to determine whether virtual gastric band (VGB) hypnotherapy has an effect on weight loss in overweight adults, compared to relaxation hypnotherapy and a self-directed diet. Levels of weight loss and gain ranged from -17 kg to +4.7 kg in the VGB hypnotherapy group and -9.3 kg to +7.8 kg in the relaxation group. There was no significant difference between VGB hypnotherapy as a main effect on weight loss, (X(2) = 0.67, p = .41, df = 1) and there was no evidence of differential weight loss over time, (X(2) = 4.2, p = .64, df = 6). Therefore, the authors conclude that there was no significant difference between VGB hypnotherapy and the relaxation hypnotherapy.

Fault evaluation and adaptive threshold detection of helicopter pilot ...

African Journals Online (AJOL)

Hitherto, in the field of aerospace science and industry, some acceptable results from control behavior of human operator (pilot), are caught using usual methods. However, very fewer research, has been done based on personal characteristics. The performed investigations, show that many of happened faults (especially in ...

Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses

Directory of Open Access Journals (Sweden)

Ruth H. Keogh

2016-01-01

Full Text Available Abstract Background Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Methods Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. Results The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Conclusions Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

Effect of Playful Balancing Training - A Pilot Randomized Controlled Trial

DEFF Research Database (Denmark)

Lund, Henrik Hautop; Jessen, Jari Due

2013-01-01

We used the modular playware in the form of modular interactive tiles for playful training of community-dwelling elderly with balancing problem. During short-term play on the modular interactive tiles, the elderly were playing physical, interactive games that were challenging their dynamic balance...... increase in balancing performance (DGI score: 21.3) after short-term playful training with the modular interactive tiles, whereas the control group remained with a score indicating balancing problems and risk of falling (DGI score: 16.6). The small pilot randomized controlled trial suggests...... that the playful interaction with the modular interactive tiles has a significant effect even after a very short time of play. The average total training time to obtain the statistical significant effect amounted to just 2h45m....

Towards an Improved Pilot-Vehicle Interface for Highly Automated Aircraft: Evaluation of the Haptic Flight Control System

Science.gov (United States)

Schutte, Paul; Goodrich, Kenneth; Williams, Ralph

2012-01-01

The control automation and interaction paradigm (e.g., manual, autopilot, flight management system) used on virtually all large highly automated aircraft has long been an exemplar of breakdowns in human factors and human-centered design. An alternative paradigm is the Haptic Flight Control System (HFCS) that is part of NASA Langley Research Center s Naturalistic Flight Deck Concept. The HFCS uses only stick and throttle for easily and intuitively controlling the actual flight of the aircraft without losing any of the efficiency and operational benefits of the current paradigm. Initial prototypes of the HFCS are being evaluated and this paper describes one such evaluation. In this evaluation we examined claims regarding improved situation awareness, appropriate workload, graceful degradation, and improved pilot acceptance. Twenty-four instrument-rated pilots were instructed to plan and fly four different flights in a fictitious airspace using a moderate fidelity desktop simulation. Three different flight control paradigms were tested: Manual control, Full Automation control, and a simplified version of the HFCS. Dependent variables included both subjective (questionnaire) and objective (SAGAT) measures of situation awareness, workload (NASA-TLX), secondary task performance, time to recognize automation failures, and pilot preference (questionnaire). The results showed a statistically significant advantage for the HFCS in a number of measures. Results that were not statistically significant still favored the HFCS. The results suggest that the HFCS does offer an attractive and viable alternative to the tactical components of today s FMS/autopilot control system. The paper describes further studies that are planned to continue to evaluate the HFCS.

Numerical Investigations of Dynamic Stall Control

Directory of Open Access Journals (Sweden)

Florin FRUNZULICA

2014-04-01

Full Text Available In this paper we investigated numerically the dynamic stall phenomenon and the possibilities to control it, with application to vertical axis wind turbines (for urban users. The Phenomenon appear at low tip speed ratio (TSR<4 and it has a great impact on structural integrity of the wind turbine and power performances. For this reason we performed a computational study of dynamic stall around NACA 0012 airfoil in pitching motion at relative low Reynolds number (105. Also, we performed the same analysis for four flow control methods: two passive (Gurney flap and slot and two active (blowing jet on the rounded trailing edge and synthetic jet periodically activated. The Results are compared to those of an existing experimental case test.

Developing and pilot testing of a tool for "clinicosocial case study" assessment of community medicine residents.

Science.gov (United States)

Gohel, Manisha; Singh, Uday Shankar; Bhanderi, Dinesh; Phatak, Ajay

2016-01-01

Practical and clinical skills teaching should constitute a core part of the postgraduate curriculum of Community Medicine. The clinicosocial case study is a method to enhance learners' skills but there is no generally accepted organized system of formative assessment and structured feedback to guide students. A new tool based on the principles of mini-Clinical Evaluation Exercise (mini CEX) was developed and pilot tested as a 'clinicosocial case study' assessment of community medicine residents with feedback as a core component. Ten core domains of clinicosocial skills were identified after reviewing the relevant literature and input from local experts in community medicine and medical education. We pilot tested the tool with eight faculty members to assess five residents during clinicosocial case presentations on a variety of topics. Kappa statistic and Bland Altman plots were used to assess agreement between faculty members' average assessment scores. Cronbach's alpha was used to test the internal consistency with faculty members as domains. All 95% confidence limits using the Bland-Altman method were within the predetermined limit of 2 points. The overall Kappa between two faculty members was fair ranging from 0.2 to 0.3. Qualitative feedback revealed that both faculty and residents were enthusiastic about the process but faculty suggested further standardization, while residents suggested streamlining of the process. This new assessment tool is available for objective and unbiased assessment of residents through 'clinicosocial case study,' which enriches learning through comprehensive feedback. Further validation in different settings is needed.

Analysis of empty ATLAS pilot jobs

CERN Document Server

Love, Peter; The ATLAS collaboration

2016-01-01

The pilot model used by the ATLAS production system has been in use for many years. The model has proven to be a success with many advantages over push models. However one of the negative side-effects of using a pilot model is the presence of 'empty pilots' running on sites which consume a small amount of walltime and not running a useful payload job. The impact on a site can be significant with previous studies showing a total 0.5% walltime usage with no benefit to either the site or to ATLAS. Another impact is the number of empty pilots being processed by a site's Compute Element and batch system which can be 5% of the total number of pilots being handled. In this paper we review the latest statistics using both ATLAS and site data and highlight edge cases where the number of empty pilots dominate. We also study the effect of tuning the pilot factories to reduce the number of empty pilots.

A pilot study using residual newborn dried blood spots to assess the potential role of cytomegalovirus and Toxoplasma gondii in the etiology of congenital hydrocephalus.

Science.gov (United States)

Simeone, Regina M; Rasmussen, Sonja A; Mei, Joanne V; Dollard, Sheila C; Frias, Jaime L; Shaw, Gary M; Canfield, Mark A; Meyer, Robert E; Jones, Jeffrey L; Lorey, Fred; Honein, Margaret A

2013-07-01

Congenital hydrocephalus is a condition characterized by accumulation of cerebrospinal fluid in the ventricles of the brain. Prenatal infections are risk factors for some birth defects. This pilot study investigated whether residual dried blood spots (DBS) could be used to assess infections as risk factors for birth defects by examining the associations between prenatal infection with Toxoplasma gondii (T. gondii) or cytomegalovirus (CMV) with congenital hydrocephalus. Case-infants with hydrocephalus (N=410) were identified among live-born infants using birth defects surveillance systems in California, North Carolina, and Texas. Control-infants without birth defects were randomly selected from the same geographic areas and time periods as case-infants (N=448). We tested residual DBS from case- and control-infants for T. gondii immunoglobulin M and CMV DNA. When possible, we calculated crude odds ratios (cORs) and confidence intervals (CIs). Evidence for prenatal T. gondii infection was more common among case-infants (1.2%) than control-infants (0%; p=0.11), and evidence for prenatal CMV infection was higher among case-infants (1.5%) than control-infants (0.7%; cOR: 2.3; 95% CI: 0.48, 13.99). Prenatal infections with T. gondii and CMV occurred more often among infants with congenital hydrocephalus than control-infants, although differences were not statistically significant. This pilot study highlighted some challenges in using DBS to examine associations between certain infections and birth defects, particularly related to reduced sensitivity and specimen storage conditions. Further study with increased numbers of specimens and higher quality specimens should be considered to understand better the contribution of these infections to the occurrence of congenital hydrocephalus. Copyright © 2013 Wiley Periodicals, Inc.

Flight deck human factors issues for National Airspace System (NAS) en route controller pilot data link communications (CPDLC)

Science.gov (United States)

2017-05-01

Fundamental differences exist between transmissions of Air Traffic Control clearances over voice and those transmitted via Controller Pilot Data Link Communications (CPDLC). This paper provides flight deck human factors issues that apply to processin...

User Participation in Pilot Implementation

DEFF Research Database (Denmark)

Torkilsheyggi, Arnvør Martinsdóttir á; Hertzum, Morten

2014-01-01

Pilot implementations provide users with real-work experiences of how a system will affect their daily work before the design of the system is finalized. On the basis of a pilot implementation of a system for coordinating the transport of patients by hospital porters, we investigate pilot...... implementation as a method for participatory design. We find that to foster participation and learning about user needs a pilot implementation must create a space for reflecting on use, in addition to the space for using the pilot system. The space for reflection must also exist during the activities preparing...... the use of the pilot system because the porters and nurses learned about their needs throughout the pilot implementation, not just during use. Finally, we discuss how the scope and duration of a pilot implementation influence the conditions for participation....

A dual-task home-based rehabilitation programme for improving balance control in patients with acquired brain injury: a single-blind, randomized controlled pilot study.

Science.gov (United States)

Peirone, Eliana; Goria, Paolo Filiberto; Anselmino, Arianna

2014-04-01

To evaluate the safety, feasibility and effectiveness of a dual-task home-based rehabilitation programme on balance impairments among adult patients with acquired brain injury. Single-blind, randomized controlled pilot study. Single rehabilitation centre. Sixteen participants between 12 and 18 months post-acquired brain injury with balance impairments and a score task home-based programme six days a week for seven weeks. The primary outcome measure was the Balance Evaluation System Test; secondary measures were the Activities-specific Balance Confidence Scale and Goal Attainment Scaling. At the end of the pilot study, the intervention group showed significantly greater improvement in Balance Evaluation System Test scores (17.87, SD 6.05) vs. the control group (5.5, SD 3.53; P = 0.008, r = 0.63). There was no significant difference in improvement in Activities-specific Balance Confidence Scale scores between the intervention group (25.25, SD 25.51) and the control group (7.00, SD 14.73; P = 0.11, r = 0.63). There was no significant improvement in Goal Attainment Scaling scores in the intervention (19.37, SD 9.03) vs. the control group (16.28, SD 6.58; P = 0.093, r = 0.63). This pilot study shows the safety, feasibility and short-term benefit of a dual-task home-based rehabilitation programme to improve balance control in patients with acquired brain injury. A sample size of 26 participants is required for a definitive study.

The impact of transition training on adapting to Technically Advanced Aircraft at regional airlines: Perceptions of pilots and instructor pilots

Science.gov (United States)

di Renzo, John Carl, Jr.

Scope and method of study. The purpose of this study was to test a hypothesis about pilot and instructor pilot perceptions of how effectively pilots learn and use new technology, found in Technically Advanced Aircraft (TAA), given initial type of instrumentation training. New aviation technologies such as Glass Cockpits in technically advanced aircraft are complex and can be difficult to learn and use. The research questions focused on the type of initial instrumentation training to determine the differences among pilots trained using various types of instrumentation ranging from aircraft equipped with traditional analog instrumentation to aircraft equipped with glass cockpits. A convenience sample of Pilots in Training (PT) and Instructor Pilots (IP) was selected from a regional airline. The research design used a mixed methodology. Pilots in training completed a thirty-two question quantitative questionnaire and instructor pilots completed a five question qualitative questionnaire. Findings and conclusions. This investigation failed to disprove the null hypothesis. The type of instrumentation training has no significant effect on newly trained regional airline pilot perceived ability to adapt to advanced technology cockpits. Therefore, no evidence exists from this investigation to support the early introduction and training of TAA. While the results of this investigation were surprising, they are nonetheless, instructive. Even though it would seem that there would be a relationship between exposure to and use of technically advanced instrumentation, apparently there was no perceived relationship for this group of airline transport pilots. However, a point of interest is that these pilots were almost evenly divided in their opinion of whether or not their previous training had prepared them for transition to TAA. The majority also believed that the type of initial instrumentation training received does make a difference when transitioning to TAA. Pilots believed

Real-Time Optimization for use in a Control Allocation System to Recover from Pilot Induced Oscillations

Science.gov (United States)

Leonard, Michael W.

2013-01-01

Integration of the Control Allocation technique to recover from Pilot Induced Oscillations (CAPIO) System into the control system of a Short Takeoff and Landing Mobility Concept Vehicle simulation presents a challenge because the CAPIO formulation requires that constrained optimization problems be solved at the controller operating frequency. We present a solution that utilizes a modified version of the well-known L-BFGS-B solver. Despite the iterative nature of the solver, the method is seen to converge in real time with sufficient reliability to support three weeks of piloted runs at the NASA Ames Vertical Motion Simulator (VMS) facility. The results of the optimization are seen to be excellent in the vast majority of real-time frames. Deficiencies in the quality of the results in some frames are shown to be improvable with simple termination criteria adjustments, though more real-time optimization iterations would be required.

Multi-Stakeholder Case Prioritization in Digital Investigations

Directory of Open Access Journals (Sweden)

Joshua I. James

2014-09-01

Full Text Available This work examines the problem of case prioritization in digital investigations for better utilization of limited criminal investigation resources. Current methods of case prioritization, as well as observed prioritization methods used in digital forensic investigation laboratories are examined. After, a multi-stakeholder approach to case prioritization is given that may help reduce reputational risk to digital forensic laboratories while improving resource allocation. A survey is given that shows differing opinions of investigation priority between Law Enforcement and the public that is used in the development of a prioritization model. Finally, an example case is given to demonstrate the practicality of the proposed method.

Individual traffic-related air pollution and new onset adult asthma: A GIS-based pilot study

Energy Technology Data Exchange (ETDEWEB)

Sherson, D.; Lysbeck Hansen, C. (Hospital of Vejle, Dept. of Occupational and Environmental Medicine, (Denmark)); Solvang Jensen, S.; Hertel, O. (Univ. of Aarhus, National Environmental Research Institute (Denmark)); Baelum, J. (Odense Univ. Hospital, Dep. of Occupational and Environmental Medicine (Denmark)); Skadhauge, L. (Haderslev Hospital, Dep. of Occupational and Environmental Medicine (Denmark)); Siersted, H.C. (Odense Univ. Hospital, Dep. of Respiratory Medicine (Denmark)); Omland, OE. (Aalborg Hospital, Dep. of Occupational Medicine (Denmark)); Thomsen, G. (South-West Jutland Hospital Esbjerg, Dep. of Occupational and Environmental Medicine (Denmark)); Sigsgaard, T. (Univ. of Aarhus, Institute of Occupational and Environmental Medicine (Denmark))

2008-03-15

The objective of this pilot study is to investigate the relation between asthma and wheeze debut and individually estimated exposure to traffic-related air pollutants with a validated exposure system (AirGIS). A non-smoking cohort with recently acquired asthma or wheeze as well as matched controls was identified from a large cross-sectional study. All residential and working addresses with corresponding time periods for a 10 year period were successfully identified for all study participants (N=33) and exposure estimated for both urban background and street level. Individual levels of air pollutants in the years preceding debut of asthma or wheeze were analyzed using survival analysis. No significant correlations between exposure levels and onset of disease or symptom were demonstrated. A tendency towards higher levels of nitrogen oxides exposure during the year prior to debut was seen in wheeze cases. Substantial problems in determining time of onset were encountered. It is recommended that the analytic methods developed in this pilot study are used in a larger prospective cohort to investigate individual trafficrelated air pollutants as a risk factor for the development of new asthma and wheeze. (au)

Case-control studies in neurosurgery.

Science.gov (United States)

Nesvick, Cody L; Thompson, Clinton J; Boop, Frederick A; Klimo, Paul

2014-08-01

Observational studies, such as cohort and case-control studies, are valuable instruments in evidence-based medicine. Case-control studies, in particular, are becoming increasingly popular in the neurosurgical literature due to their low cost and relative ease of execution; however, no one has yet systematically assessed these types of studies for quality in methodology and reporting. The authors performed a literature search using PubMed/MEDLINE to identify all studies that explicitly identified themselves as "case-control" and were published in the JNS Publishing Group journals (Journal of Neurosurgery, Journal of Neurosurgery: Pediatrics, Journal of Neurosurgery: Spine, and Neurosurgical Focus) or Neurosurgery. Each paper was evaluated for 22 descriptive variables and then categorized as having either met or missed the basic definition of a case-control study. All studies that evaluated risk factors for a well-defined outcome were considered true case-control studies. The authors sought to identify key features or phrases that were or were not predictive of a true case-control study. Those papers that satisfied the definition were further evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist. The search detected 67 papers that met the inclusion criteria, of which 32 (48%) represented true case-control studies. The frequency of true case-control studies has not changed with time. Use of odds ratios (ORs) and logistic regression (LR) analysis were strong positive predictors of true case-control studies (for odds ratios, OR 15.33 and 95% CI 4.52-51.97; for logistic regression analysis, OR 8.77 and 95% CI 2.69-28.56). Conversely, negative predictors included focus on a procedure/intervention (OR 0.35, 95% CI 0.13-0.998) and use of the word "outcome" in the Results section (OR 0.23, 95% CI 0.082-0.65). After exclusion of nested case-control studies, the negative correlation between focus on a procedure

Limited Investigation of the Effects of Elevator Rate Limiting and Stick Dynamics on Longitudinal Pilot Induced Oscillations (HAVE GRIP)

National Research Council Canada - National Science Library

Peters, Patrick

1996-01-01

This report presents the results of the HAVE GRIP flight test program. This program performed a limited investigation of the effects of stick dynamics and elevator rate limiting on longitudinal pilot induced oscillations (PIOs...

Using Robots at Home to Support Patients With Chronic Obstructive Pulmonary Disease: Pilot Randomized Controlled Trial.

Science.gov (United States)

Broadbent, Elizabeth; Garrett, Jeff; Jepsen, Nicola; Li Ogilvie, Vickie; Ahn, Ho Seok; Robinson, Hayley; Peri, Kathryn; Kerse, Ngaire; Rouse, Paul; Pillai, Avinesh; MacDonald, Bruce

2018-02-13

Socially assistive robots are being developed for patients to help manage chronic health conditions such as chronic obstructive pulmonary disease (COPD). Adherence to medication and availability of rehabilitation are suboptimal in this patient group, which increases the risk of hospitalization. This pilot study aimed to investigate the effectiveness of a robot delivering telehealth care to increase adherence to medication and home rehabilitation, improve quality of life, and reduce hospital readmission compared with a standard care control group. At discharge from hospital for a COPD admission, 60 patients were randomized to receive a robot at home for 4 months or to a control group. Number of hospitalization days for respiratory admissions over the 4-month study period was the primary outcome. Medication adherence, frequency of rehabilitation exercise, and quality of life were also assessed. Implementation interviews as well as benefit-cost analysis were conducted. Intention-to-treat and per protocol analyses showed no significant differences in the number of respiratory-related hospitalizations between groups. The intervention group was more adherent to their long-acting inhalers (mean number of prescribed puffs taken per day=48.5%) than the control group (mean 29.5%, P=.03, d=0.68) assessed via electronic recording. Self-reported adherence was also higher in the intervention group after controlling for covariates (P=.04). The intervention group increased their rehabilitation exercise frequency compared with the control group (mean difference -4.53, 95% CI -7.16 to -1.92). There were no significant differences in quality of life. Of the 25 patients who had the robot, 19 had favorable attitudes. This pilot study suggests that a homecare robot can improve adherence to medication and increase exercise. Further research is needed with a larger sample size to further investigate effects on hospitalizations after improvements are made to the robots. The robots could be

Incorporation of nisin in natural casing for the control of spoilage microorganisms in vacuum packaged sausage

Directory of Open Access Journals (Sweden)

Joyce Regina de Barros

2010-12-01

Full Text Available This study aimed to evaluate the effectiveness of natural casing treatment with nisin and phosphoric acid on control of spoilage microorganisms in vacuum packaged sausages. Ovine casings were dipped in the following baths: 1 0.1% food grade phosphoric acid; 2 5.0 mg/L nisin; 3 0.1% phosphoric acid and 5.0 mg/L nisin; and 4 sterile water (control. The sausages were produced in a pilot plant, stuffed into the pretreated natural casings, vacuum packaged and stored at 4 and 10 °C for 56 days. The experiments were performed according to a full factorial design 2³, totalizing 8 treatments that were repeated in 3 blocks. Aerobic plate counts and lactic acid bacteria analysis were conducted at 1, 14, 28, 42 and 56 days of storage. Treatment of casings with phosphoric acid 0.1% alone did not inhibit the growth of lactic acid bacteria and reduced the aerobic plate count by 1 log. The activity of nisin against lactic acid bacteria was enhanced by the addition of phosphoric acid, demonstrating a synergistic effect. Furthermore nisin activity was more evident at lower storage temperature (4 ºC. Therefore treatment of the natural casings with nisin and phosphoric acid, combined with low storage temperature, are obstacles that present a potential for controlling the growth of lactic acid bacteria in vacuum packaged sausage.

U.S. Airline Transport Pilot International Flight Language Experiences, Report 4: Non-Native English-Speaking Controllers Communicating with Native English-Speaking Pilots

Science.gov (United States)

2010-08-01

effortless flow. Varies speech flow for stylistic effect, e.g., to emphasize a point. Uses appropriate discourse markers and connectors spontaneously. L3...were equally represented in Cognitive Aspects of Cross-Linguistic Communica- tion (15%), Pilot Controller Interactions (15%), and Verification...Confirmation of Messages (15%). Cognitive Aspects of Cross-linguistic Communication The speed of communication and understanding is probably a comfortable

Intraperitoneal Vancomycin Plus Either Oral Moxifloxacin or Intraperitoneal Ceftazidime for the Treatment of Peritoneal Dialysis-Related Peritonitis: A Randomized Controlled Pilot Study.

Science.gov (United States)

Xu, Rong; Yang, Zhikai; Qu, Zhen; Wang, Huan; Tian, Xue; Johnson, David W; Dong, Jie

2017-07-01

Intraperitoneal administration of antibiotics is recommended as a first treatment for managing peritoneal dialysis (PD)-related peritonitis. However, the efficacy of oral administration of quinolones has not been well studied. Randomized controlled pilot study. 80 eligible patients with PD-related peritonitis from Peking University First Hospital (40 in each arm). Intraperitoneal vancomycin, 1g, every 5 days plus oral moxifloxacin, 400mg, every day (treatment group) versus intraperitoneal vancomycin, 1g, every 5 days plus intraperitoneal ceftazidime, 1g, every day (control group). The primary end point was complete resolution of peritonitis, and secondary end points were primary or secondary treatment failure. PD effluent white blood cell count. Baseline demographic and clinical characteristics of the 2 groups were comparable. There were 24 and 22 Gram-positive organisms, 6 and 7 Gram-negative organisms, 9 and 10 culture-negative samples, and 1 and 1 fungal sample in the treatment and control groups, respectively. Complete resolution of peritonitis was achieved in 78% and 80% of cases in the treatment and control groups, respectively (OR, 0.86; 95% CI, 0.30-2.52; P=0.8). There were 3 and 1 cases of relapse in the treatment and control groups, respectively. Primary and secondary treatment failure rates were not significantly different (33% vs 20% and 10% vs 13%, respectively). In each group, there was 1 peritonitis-related death and 6 transfers to hemodialysis therapy. During the 3-month follow-up period, 7 and 3 successive episodes of peritonitis occurred in the treatment and control groups, respectively. Only 2 adverse drug reactions (mild nausea and mild rash, respectively) were observed in the 2 groups. Sample size was relatively small and the eligibility ratio was low. Also, the number of peritonitis episodes was low, limiting the power to detect a difference between groups. This pilot study suggests that intraperitoneal vancomycin with oral moxifloxacin is a

Piloted simulation of an air-ground profile negotiation process in a time-based Air Traffic Control environment

Science.gov (United States)

Williams, David H.; Green, Steven M.

1993-01-01

Historically, development of airborne flight management systems (FMS) and ground-based air traffic control (ATC) systems has tended to focus on different objectives with little consideration for operational integration. A joint program, between NASA's Ames Research Center (Ames) and Langley Research Center (Langley), is underway to investigate the issues of, and develop systems for, the integration of ATC and airborne automation systems. A simulation study was conducted to evaluate a profile negotiation process (PNP) between the Center/TRACON Automation System (CTAS) and an aircraft equipped with a four-dimensional flight management system (4D FMS). Prototype procedures were developed to support the functional implementation of this process. The PNP was designed to provide an arrival trajectory solution which satisfies the separation requirements of ATC while remaining as close as possible to the aircraft's preferred trajectory. Results from the experiment indicate the potential for successful incorporation of aircraft-preferred arrival trajectories in the CTAS automation environment. Fuel savings on the order of 2 percent to 8 percent, compared to fuel required for the baseline CTAS arrival speed strategy, were achieved in the test scenarios. The data link procedures and clearances developed for this experiment, while providing the necessary functionality, were found to be operationally unacceptable to the pilots. In particular, additional pilot control and understanding of the proposed aircraft-preferred trajectory, and a simplified clearance procedure were cited as necessary for operational implementation of the concept.

National Grid Deep Energy Retrofit Pilot

Energy Technology Data Exchange (ETDEWEB)

Neuhauser, K.

2012-03-01

Through discussion of five case studies (test homes), this project evaluates strategies to elevate the performance of existing homes to a level commensurate with best-in-class implementation of high-performance new construction homes. The test homes featured in this research activity participated in Deep Energy Retrofit (DER) Pilot Program sponsored by the electric and gas utility National Grid in Massachusetts and Rhode Island. Building enclosure retrofit strategies are evaluated for impact on durability and indoor air quality in addition to energy performance. Evaluation of strategies is structured around the critical control functions of water, airflow, vapor flow, and thermal control. The aim of the research project is to develop guidance that could serve as a foundation for wider adoption of high performance, 'deep' retrofit work. The project will identify risk factors endemic to advanced retrofit in the context of the general building type, configuration and vintage encountered in the National Grid DER Pilot. Results for the test homes are based on observation and performance testing of recently completed projects. Additional observation would be needed to fully gauge long-term energy performance, durability, and occupant comfort.

No Association between Mycotoxin Exposure and Autism: A Pilot Case-Control Study in School-Aged Children

Directory of Open Access Journals (Sweden)

Jennifer Duringer

2016-07-01

Full Text Available Evaluation of environmental risk factors in the development of autism spectrum disorder (ASD is needed for a more complete understanding of disease etiology and best approaches for prevention, diagnosis, and treatment. A pilot experiment in 54 children (n = 25 ASD, n = 29 controls; aged 12.4 ± 3.9 years screened for 87 urinary mycotoxins via liquid chromatography-tandem mass spectrometry to assess current exposure. Zearalenone, zearalenone-4-glucoside, 3-acetyldeoxynivalenol, and altenuene were detected in 9/54 (20% samples, most near the limit of detection. No mycotoxin/group of mycotoxins was associated with ASD-diagnosed children. To identify potential correlates of mycotoxin presence in urine, we further compared the nine subjects where a urinary mycotoxin was confirmed to the remaining 45 participants and found no difference based on the presence or absence of mycotoxin for age (t-test; p = 0.322, gender (Fisher’s exact test; p = 0.456, exposure or not to selective serotonin reuptake inhibitors (Fisher’s exact test; p = 0.367, or to other medications (Fisher’s exact test; p = 1.00. While no positive association was found, more sophisticated sample preparation techniques and instrumentation, coupled with selectivity for a smaller group of mycotoxins, could improve sensitivity and detection. Further, broadening sampling to in utero (mothers and newborn-toddler years would cover additional exposure windows.

Pilot Study on the Investigation of Tear Fluid Biomarkers as an Indicator of Ocular, Neurological, and Immunological Health in Astronauts

Science.gov (United States)

Morton, Stephen; Crucian, Brian; Hagan, Suzanne; Satyamitra, Merriline; Daily, Anna

2018-01-01

The purpose of this pilot study is to investigate the collection, preparation, and analysis of tear biomarkers as a means of assessing ocular, neurological, and immunological health. At present, no published data exists on the cytokine profiles of tears from astronauts exposed to long periods of microgravity and space irradiations. In addition, no published data exist on cytokine (biomarker) profiles of tears that have been collected from irradiated non-human biological systems (primates and other animal models). A goal for the proposed pilot study is to discover novel tear biomarkers which can help inform researchers, clinicians, epidemiologist and healthcare providers about the health status of a living biological system, as well as informing them when a disease state is triggered. This would be done via analysis of the onset of expression of pro-inflammatory cytokines, leading up to the full progression of a disease (i.e. cancer, loss of vision, radiation-induced oxidative stress, cardiovascular disorders, fibrosis in major organs, bone loss). Another goal of this pilot study is to investigate the state of disease against proposed medical countermeasures, in order to determine whether the countermeasures are efficacious in preventing or mitigating these injuries. An example of an up and coming tear biomarker technology, Ascendant Dx, a clinical stage diagnostic company, is developing a screening test to detect breast cancer using proteins from tears. The team utilized Liquid Chromatography -Mass Spectrometry with Mass analysis (LC MS/MS) as a discovery platform followed by validation with ELISA to come up with a panel of protein biomarkers that can differentiate breast cancer samples from control ("cancer free") samples with results far surpassing the results of imaging techniques in use today. Continued research into additional proteins is underway to increase the sensitivity and specificity of the test and development efforts are on the way to transfer the

The effect of control and display lag on unmanned air system internal pilot manual landing performance

Science.gov (United States)

Lloyd, Marshall Everett

An important characteristic of UASs is lag because it can become a considerable challenge to successful human-in-the-loop control. As such, UASs are designed and configured to minimize system lag, though this can increase acquisition and operation costs considerably. In an effort to cut costs, an organization may choose to accept greater risk and deploy a UAS with high system lag. Before this risk can be responsibly accepted, it must be quantified. While many studies have examined system lag, very few have been able to quantify the risk that various levels of lag pose to an internally piloted, manually landed UAS. This study attempted to do so by evaluating pilot landing performance in a simulator with 0 ms, 240 ms, and 1000 ms of additional lag. Various measures were used, including a novel coding technique. Results indicated that 1000 ms of lag was unsafe by all measures. They also indicate that 240 ms of lag degrades performance, but participants were able to successfully land the simulated aircraft. This study showed the utility of using several measures to evaluate the effect of lag on landing performance and it helped demonstrate that while 1000 ms poses a high risk, 240 ms of lag may be a much more manageable risk. Future research suggested by this research includes: investigating lag between 240 ms and 1000 ms, introducing different weather phenomena, developing system lag training techniques for operators, and investigating the effect of aides such as predictive displays and autopilot-assisted recovery.

Case-control studies in diabetes. Do they really use a case-control design?

Science.gov (United States)

Ramos, Analía; Mendoza, Lilian Cristina; Rabasa, Fernanda; Bolíbar, Ignasi; Puig, Teresa; Corcoy, Rosa

2017-07-01

Studies defined as case-control do not always use this design. We aimed to estimate the frequency of mislabelled case-control studies in published articles in the area of diabetes and to identify the predictors of incorrect labelling. We searched Medline and Web of Science for articles with "diabetes" and "case control" in title and filtered for language (English/Romance) and period (January 2010-December 2014). Inclusion criteria were: (1) statement to use a case-control design in title, (2) to be a final full-length publication and (3) to have original data in the area of diabetes. Three independent reviewers went through titles, looked for full texts and reviewed them. Discrepancies were settled with a fourth reviewer. Expert epidemiologist advice was requested in case of doubt. case-control mislabelling; addressed predictors: publication year, journal impact factor and journal subject. proportion of mislabelled CC articles and assessment of predictors by multivariate logistic regression analysis. We retrieved 362 articles, 251 of them fulfilling inclusion criteria. The proportion of mislabelled CC studies was 43.8% (confidence interval 95% 37.7-50.0%). Most mislabelled studies had a cross-sectional design (82.7%). Predictors of mislabelling were publication year, journal impact factor and journal area. A relevant subset of studies defined as case-control in the area of diabetes correspond to mislabelled cross-sectional studies. Incorrect labelling misleads readers regarding the interpretation of results and the cause-effect hypothesis. Researchers, reviewers and editors should be aware of and commit to settle this issue.

Benfotiamine in the treatment of diabetic polyneuropathy--a three-week randomized, controlled pilot study (BEDIP study).

Science.gov (United States)

Haupt, E; Ledermann, H; Köpcke, W

2005-02-01

The aim of the study was to evaluate the efficacy of benfotiamine administered over three weeks (allithiamine; a lipid-soluble vitamin B1 prodrug with high bioavailability) to patients with diabetic polyneuropathy in a randomized, placebo-controlled, double-blind, two-center pilot study. Forty inpatients (23 male, 18 female, age range 18 - 70 years) with a history of type 1 or 2 diabetes and polyneuropathy of not longer than two years, were included in the study. Twenty Patients received two 50 mg benfotiamine tablets four times daily and 20 patients received placebo over the three-week study period. Two clinical units were involved with 10 patients receiving placebo and 10 patients benfotiamine in each. The neuropathy score according to Katzenwadel et al. [1987] was used to evaluate symptoms of polyneuropathy, vibration perception threshold and both the physician's and the patient's own assessment were documented. A statistically significant (p = 0.0287) improvement in the neuropathy score was observed in the group given active drug when compared to the placebo-treated controls. There was no statistically significant change observed in the tuning fork test. The most pronounced effect on complaints was a decrease in pain (p = 0.0414). More patients in the benfotiamine-treated group than in the placebo group considered their clinical condition to have improved (p = 0.052). No side effects attributable to benfotiamine were observed. The differences between the groups cannot be attributed to a change in metabolic parameters since there were no significant alterations in the HbA1 levels and blood sugar profiles. The body mass index of the two groups did not differ. This pilot investigation (BEDIP Study) has confirmed the results of two earlier randomized controlled trials and has provided further evidence for the beneficial effects of benfotiamine in patients with diabetic neuropathy.

Effects of malicious ocular laser exposure in commercial airline pilots.

Science.gov (United States)

Palakkamanil, Mathew M; Fielden, Michael P

2015-12-01

Intentional malicious laser strikes on commercial pilots are committed by individuals who target a laser into airplane cockpits during takeoff and landing. Because laser exposure to pilots is a relatively new but growing occurrence, our study investigates the ocular effect of this laser exposure in pilots. Retrospective chart review by a single ophthalmologist. All commercial airline pilots (58 male, 3 female) who experienced a laser strike while flying between April 2012 and November 2014 who presented to our clinic were included. A retrospective chart review was performed in a retinal specialist's practice. Ocular assessment was performed within 3 days of laser exposure. A complete ophthalmic evaluation was conducted, including Early Treatment Diabetic Retinopathy Study visual acuity, colour vision, visual fields, intraocular pressure, slit-lamp examination, dilated fundus examination, colour fundus photographs, and ocular coherence tomography. Sixty-four laser strike incidents involving commercial pilots were included. All pilots in the study experienced some degree of immediate ocular irritation or light sensitivity. No definite cases of ocular damage were attributed to laser strikes. No pilot had any functional ocular deficits. Our study revealed that laser strikes on aircraft did not result in permanent visual functional or structural deficits. However, laser strikes cause immediate visual effects, including glare, flash blindness, and ocular irritation that can interfere with a pilot's visual function. Given the widespread accessibility of high-power lasers and the rapid increase in incidents, laser strikes threaten to jeopardize aviation safety unless effective preventative measures are put in place. Copyright © 2015 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

Pilot and pilot-commercial plants for reprocessing spent fuels of FBR type reactors

International Nuclear Information System (INIS)

Shaldaev, V.S.; Sokolova, I.D.

1988-01-01

A review of modern state of investigations on the FBR mixed oxide uranium-plutonium fuel reprocessing abroad is given. Great Britain and France occupy the leading place in this field, operating pilot plants of 5 tons a year capacity. Technology of spent fuel reprocessing and specific features of certain stages of the technological process are considered. Projects of pilot and pilot-commercial plants of Great Britain, France, Japan, USA are described. Economic problems of the FBR fuel reprocessing are touched upon

Investigation of high-alpha lateral-directional control power requirements for high-performance aircraft

Science.gov (United States)

Foster, John V.; Ross, Holly M.; Ashley, Patrick A.

1993-01-01

Designers of the next-generation fighter and attack airplanes are faced with the requirements of good high angle-of-attack maneuverability as well as efficient high speed cruise capability with low radar cross section (RCS) characteristics. As a result, they are challenged with the task of making critical design trades to achieve the desired levels of maneuverability and performance. This task has highlighted the need for comprehensive, flight-validated lateral-directional control power design guidelines for high angles of attack. A joint NASA/U.S. Navy study has been initiated to address this need and to investigate the complex flight dynamics characteristics and controls requirements for high angle-of-attack lateral-directional maneuvering. A multi-year research program is underway which includes groundbased piloted simulation and flight validation. This paper will give a status update of this program that will include a program overview, description of test methodology and preliminary results.

Development and pilot of Case Manager: a virtual-patient experience for veterinary students.

Science.gov (United States)

Byron, Julie K; Johnson, Susan E; Allen, L Clare V; Brilmyer, Cheryl; Griffiths, Robert P

2014-01-01

There is an increasing demand in veterinary education to engage students, teach and reinforce clinical reasoning, and provide access anytime/anywhere to quality learning opportunities. In addition, accrediting bodies are asking for more concrete documentation of essential clinical-skills outcomes. Unfortunately, during the clinical year in a referral hospital setting, students are at the mercy of chance regarding the types of cases they will encounter and the opportunities they will have to participate. Patient- and case-simulation technology is becoming more popular as a way to achieve these objectives in human and veterinary medical education. Many of the current options available to the veterinary medical education community to develop virtual-patient cases are too time-consuming, cost prohibitive, or difficult for the instructor or learner to use. In response, we developed a learning tool, Case Manager, which is low-cost and user-friendly. Case Manager was designed to meet the demands of veterinary education by providing students with an opportunity to cultivate clinical reasoning skills and allowing for real-time student feedback. We launched a pilot test with 37 senior veterinary medical students as part of their Small Animal Internal Medicine clinical rotation. Students reported that Case Manager increased their engagement with the material, improved diagnostic and problem-solving skills, and broadened their exposure to a variety of cases. In addition, students felt that Case Manager was superior to a more traditional, less interactive case presentation format.

Advanced Instrumentation, Information and Control (II&C) Research and Development Facility Buildout and Project Execution of LWRS II&C Pilot Projects 1 and 3

Energy Technology Data Exchange (ETDEWEB)

Ronald Farris; Johanna Oxstrand; Gregory Weatherby

2011-09-01

The U.S. Department of Energy (DOE) is sponsoring research, development, and deployment on light water reactor sustainability (LWRS), in which the Idaho National Laboratory (INL) is working closely with nuclear utilities to develop technologies and solutions to help ensure the safe operational life extension of current reactors. As technologies are introduced that change the operation of the plant, the LWRS pilot projects can help identify their best-advanced uses and help demonstrate the safety of these technologies. In early testing of operator performance given these emerging technologies will ensure the safety and usability of systems prior to large-scale deployment and costly verification and validation at the plant. The aim of these collaborations, demonstrations, and approaches are intended to lessen the inertia that sustains the current status quo of today's II&C systems technology, and to motivate transformational change and a shift in strategy to a long-term approach to II&C modernization that is more sustainable. Research being conducted under Pilot Project 1 regards understanding the conditions and behaviors that can be modified, either through process improvements and/or technology deployment, to improve the overall safety and efficiency of outage control at nuclear facilities. The key component of the research in this pilot project is accessing the delivery of information that will allow researchers to simulate the control room, outage control center (OCC) information, and plant status data. The simulation also allows researchers to identify areas of opportunity where plant operating status and outage activities can be analyzed to increase overall plant efficiency. For Pilot Project 3 the desire is to demonstrate the ability of technology deployment and the subsequent impact on maximizing the 'Collective Situational Awareness' of the various stakeholders in a commercial nuclear power plant. Specifically, the desire is to show positive

Ultrasound-guided stellate ganglion blocks combined with pharmacological and occupational therapy in Complex Regional Pain Syndrome (CRPS): a pilot case series ad interim.

Science.gov (United States)

Wei, Karin; Feldmann, Robert E; Brascher, Anne-Kathrin; Benrath, Justus

2014-12-01

This preliminary and retrospective pilot case series examines a treatment concept consisting of ultrasound-guided stellate ganglion blocks (SGBs) combined with pharmacological and occupational therapy in patients with complex regional pain syndrome (CRPS) of the hand. Efficacy of combined treatment concepts and safety of ultrasound-guided SGB have not been sufficiently investigated yet. A total number of 156 blocks were evaluated in 16 patients with CRPS in a retrospective analysis. All patients received pharmacotherapy and a standard regimen of occupational therapy offered simultaneously to the SGBs. Changes in both spontaneous and evoked pain levels were assessed by numerical pain rating score before and after the last blockade of a series. Side effects were documented. The overall mean pain reduction was 63.2% regarding spontaneous and 45.3% regarding evoked pain. Mild complications, such as hoarseness or dysphagia, occurred in 13.5% of the blocks (21 SGBs). Serious complications, such as plexus paresis or accidental puncture of vessels or other structures, did not occur. Time between symptom onset and start of treatment did not affect the extent of pain reduction. The combination of ultrasound-guided SGB and simultaneous pharmacological and occupational therapy showed encouraging treatment results under conditions of this pilot case series. Assessment of efficacy of this combined treatment concept and safety of ultrasound-guided SGB require further prospective clinical studies with larger number of participants. Wiley Periodicals, Inc.

A Pilot Randomized Controlled Trial of a Guided Self-Help Intervention to Manage Chronic Orofacial Pain.

Science.gov (United States)

Goldthorpe, Joanna; Lovell, Karina; Peters, Sarah; McGowan, Linda; Nemeth, Imola; Roberts, Christopher; Aggarwal, Vishal R

2017-01-01

To conduct a pilot trial to test the feasibility of a guided self-help intervention for chronic orofacial pain. A pilot randomized controlled trial was conducted to compare the intervention with usual treatment. A total of 37 patients with chronic orofacial pain were randomized into either the intervention group (n = 19) or the usual treatment (control) group (n = 18). Validated outcome measures were used to measure the potential effectiveness of the intervention over a number of domains: physical and mental functioning (Short Form 36 [SF-36]); anxiety and depression (Hospital Anxiety and Depression Scale [HADS]); pain intensity and interference with life (Brief Pain Inventory [BPI]); disability (Manchester Orofacial Pain Disability Scale [MOPDS]); and illness behavior (Revised Illness Perceptions Questionnaire [IPQr]). Bootstrap confidence intervals were computed for the treatment effect (ES) posttreatment and at 3 months follow-up and adjusted for baseline values of the outcome measure by using analysis of covariance. At posttreatment and the 3-month follow-up, 11 participants in the intervention group and 7 in the control group failed to complete outcome measures. The intervention was acceptable and could be feasibly delivered face to face or over the telephone. Although the pilot trial was not powered to draw conclusions about the effectiveness, it showed significant (P orofacial pain. It showed potential effectiveness on outcome domains related to functioning and illness perception. Further research is needed to understand the cost effectiveness of the intervention for chronic orofacial pain.

Feasibility and preliminary effectiveness of ice therapy in patients with an acute tear in the gastrocnemius muscle: a pilot randomized controlled trial.

Science.gov (United States)

Prins, Jan C M; Stubbe, Janine H; van Meeteren, Nico L U; Scheffers, Frans A; van Dongen, Martien C J M

2011-05-01

To investigate the feasibility of a randomized controlled trial and the preliminary effectiveness of ice therapy in the acute phase of a gastrocnemius tear for the quality of functional recovery. A pilot version of an intended prospective randomized controlled clinical trial was conducted. A total of 19 patients with an acute tear in the gastrocnemius muscle were randomly allocated to either active or control treatment. The intervention consisted of the repeated application of crushed ice. Primary outcome measures were functional capacity and reconvalescence time. Secondary outcome measures were pain and work absenteeism. The number of patients we could include within the 6-hour time window and dropping out from the pilot study were regarded as indicators of the feasibility of ice therapy. A total of 16 patients were excluded from the study because diagnosis was not made within 6 hours after onset of the complaint. The 19 patients included completed the treatment. For functional capacity, reconvalescence time, work absenteeism and pain relief, no significant differences between the intervention and control group were found. The execution of a randomized controlled trial on ice therapy for acute gastrocnemius tear is feasible though quite an enterprise. First, it is recommended to improve the recruitment processes. Second, power analysis demands inclusion of 396 participants. Preliminary effectiveness in our limited-sized trial indicates that the use of ice is not beneficial for people who receive ice therapy.

A pilot study to evaluate an efficient testing strategy for surveillance ...

African Journals Online (AJOL)

Introduction: Control strategies for schistosomiasis depend on the understanding of the population specific magnitude of the infection. We present pilot results of a testing strategy suggested by theoretical statistical investigation that lowers cost yet retains similar accuracy profile as the standard Kato-Katz technique.

Source-case investigation of Mycobacterium wolinskyi cardiac surgical site infection.

Science.gov (United States)

Dupont, C; Terru, D; Aguilhon, S; Frapier, J-M; Paquis, M-P; Morquin, D; Lamy, B; Godreuil, S; Parer, S; Lotthé, A; Jumas-Bilak, E; Romano-Bertrand, S

2016-07-01

The non-tuberculous mycobacteria (NTM) Mycobacterium wolinskyi caused bacteraemia and massive colonization of an aortic prosthesis in a patient 16 days after cardiac surgery, necessitating repeat surgery and targeted antimicrobial chemotherapy. The infection control team investigated the source and conditions of infection. Peri-operative management of the patient complied with recommendations. The environmental investigation showed that although M. wolinskyi was not recovered, diverse NTM species were present in water from point-of-use taps and heater-cooler units for extracorporeal circulation. This case and increasing evidence of emerging NTM infections in cardiac surgery led to the implementation of infection control procedures in cardiac surgery wards. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Risk factors associated with lipomyelomeningocele: a case-control study.

Science.gov (United States)

Esmaeili, Arash; Hanaei, Sara; Fadakar, Kaveh; Dadkhah, Sahar; Arjipour, Mahdi; Habibi, Zohreh; Nejat, Farideh; El Khashab, Mostafa

2013-01-01

In general, it seems that both genetic and environmental factors play important roles in the induction of neural tube defects. Lipomyelomeningocele (LipoMMC) is a rather common type of closed neural tube defect, but only limited studies have investigated the potential risk factors of this anomaly. Therefore, the purpose of this case-control study was to investigate the risk factors involved in LipoMMC formation. Various risk factors were evaluated in 35 children between 1 month and 10 years of age with LipoMMC in a hospital-based case-control study. The 2 control arms consisted of 35 children with myelomeningocele (MMC group) and 35 children with congenital anomalies other than central nervous system problems (control group). All groups were matched for age and visited the same hospital. A structured questionnaire was used for the collection of all data, including the mothers' weight and height during pregnancy, education, reproductive history, previous abortions, and socioeconomic status, as well as the parents' consanguinity and family history of the same anomalies. Univariate analysis of the children with LipoMMC compared to the control group showed that the use of periconceptional folic acid supplementation was significantly lower in the MMC and LipoMMC groups compared to the control group. In addition, comparison of the MMC and control groups revealed statistically significant differences regarding the use of folic acid and maternal obesity. In multivariate analysis, use of folic acid in the periconceptional period and during the first trimester was an independent risk factor for LipoMMC and MMC. Furthermore, maternal obesity was a significantly positive risk factor for MMC. The probable risk factors for LipoMMC were investigated in this case-control study. Consumption of folic acid in the periconceptional period and during the first trimester is an independent protective factor against LipoMMC. It seems that larger studies are needed to examine other possible

46 CFR 96.40-1 - Pilot boarding equipment.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Pilot boarding equipment. 96.40-1 Section 96.40-1... CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Pilot Boarding Equipment § 96.40-1 Pilot boarding... boat or other vessel. (b) Each vessel must have suitable pilot boarding equipment available for use on...

46 CFR 195.40-1 - Pilot boarding equipment.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Pilot boarding equipment. 195.40-1 Section 195.40-1... CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Pilot Boarding Equipment § 195.40-1 Pilot boarding... boat or other vessel. (b) Each vessel must have suitable pilot boarding equipment available for use on...

Outbreak of acute renal failure in Panama in 2006: a case-control study.

Science.gov (United States)

Rentz, E Danielle; Lewis, Lauren; Mujica, Oscar J; Barr, Dana B; Schier, Joshua G; Weerasekera, Gayanga; Kuklenyik, Peter; McGeehin, Michael; Osterloh, John; Wamsley, Jacob; Lum, Washington; Alleyne, Camilo; Sosa, Nestor; Motta, Jorge; Rubin, Carol

2008-10-01

In September 2006, a Panamanian physician reported an unusual number of patients with unexplained acute renal failure frequently accompanied by severe neurological dysfunction. Twelve (57%) of 21 patients had died of the illness. This paper describes the investigation into the cause of the illness and the source of the outbreak. Case-control and laboratory investigations were implemented. Case patients (with acute renal failure of unknown etiology and serum creatinine > 2 mg/dl) were individually matched to hospitalized controls for age (+/- 5 years), sex and admission date (< 2 days before the case patient). Questionnaire and biological data were collected. The main outcome measure was the odds of ingesting prescription cough syrup in cases and controls. Forty-two case patients and 140 control patients participated. The median age of cases was 68 years (range: 25-91 years); 64% were male. After controlling for pre-existing hypertension and renal disease and the use of angiotensin-converting enzyme inhibitors, a significant association was found between ingestion of prescription cough syrup and illness onset (adjusted odds ratio: 31.0, 95% confidence interval: 6.93-138). Laboratory analyses confirmed the presence of diethylene glycol (DEG) in biological samples from case patients, 8% DEG contamination in cough syrup samples and 22% contamination in the glycerin used to prepare the cough syrup. The source of the outbreak was DEG-contaminated cough syrup. This investigation led to the recall of approximately 60 000 bottles of contaminated cough syrup, widespread screening of potentially exposed consumers and treatment of over 100 affected patients.

A pilot randomised controlled trial of negative pressure wound therapy to treat grade III/IV pressure ulcers [ISRCTN69032034

Science.gov (United States)

2012-01-01

Background Negative pressure wound therapy (NPWT) is widely promoted as a treatment for full thickness wounds; however, there is a lack of high-quality research evidence regarding its clinical and cost effectiveness. A trial of NPWT for the treatment of grade III/IV pressure ulcers would be worthwhile but premature without assessing whether such a trial is feasible. The aim of this pilot randomised controlled trial was to assess the feasibility of conducting a future full trial of NPWT for the treatment of grade III and IV pressure ulcers and to pilot all aspects of the trial. Methods This was a two-centre (acute and community), pilot randomised controlled trial. Eligible participants were randomised to receive either NPWT or standard care (SC) (spun hydrocolloid, alginate or foam dressings). Outcome measures were time to healing of the reference pressure ulcer, recruitment rates, frequency of treatment visits, resources used and duration of follow-up. Results Three hundred and twelve patients were screened for eligibility into this trial over a 12-month recruitment period and 12/312 participants (3.8%) were randomised: 6 to NPWT and 6 to SC. Only one reference pressure ulcer healed (NPWT group) during follow-up (time to healing 79 days). The mean number of treatment visits per week was 3.1 (NPWT) and 5.7 (SC); 6/6 NPWT and 1/6 SC participants withdrew from their allocated trial treatment. The mean duration of follow-up was 3.8 (NPWT) and 5.0 (SC) months. Conclusions This pilot trial yielded vital information for the planning of a future full study including projected recruitment rate, required duration of follow-up and extent of research nurse support required. Data were also used to inform the cost-effectiveness and value of information analyses, which were conducted alongside the pilot trial. Trial registration Current Controlled Trials ISRCTN69032034. PMID:22839453

A pilot randomised controlled trial of negative pressure wound therapy to treat grade III/IV pressure ulcers [ISRCTN69032034

Directory of Open Access Journals (Sweden)

Ashby Rebecca L

2012-07-01

Full Text Available Abstract Background Negative pressure wound therapy (NPWT is widely promoted as a treatment for full thickness wounds; however, there is a lack of high-quality research evidence regarding its clinical and cost effectiveness. A trial of NPWT for the treatment of grade III/IV pressure ulcers would be worthwhile but premature without assessing whether such a trial is feasible. The aim of this pilot randomised controlled trial was to assess the feasibility of conducting a future full trial of NPWT for the treatment of grade III and IV pressure ulcers and to pilot all aspects of the trial. Methods This was a two-centre (acute and community, pilot randomised controlled trial. Eligible participants were randomised to receive either NPWT or standard care (SC (spun hydrocolloid, alginate or foam dressings. Outcome measures were time to healing of the reference pressure ulcer, recruitment rates, frequency of treatment visits, resources used and duration of follow-up. Results Three hundred and twelve patients were screened for eligibility into this trial over a 12-month recruitment period and 12/312 participants (3.8% were randomised: 6 to NPWT and 6 to SC. Only one reference pressure ulcer healed (NPWT group during follow-up (time to healing 79 days. The mean number of treatment visits per week was 3.1 (NPWT and 5.7 (SC; 6/6 NPWT and 1/6 SC participants withdrew from their allocated trial treatment. The mean duration of follow-up was 3.8 (NPWT and 5.0 (SC months. Conclusions This pilot trial yielded vital information for the planning of a future full study including projected recruitment rate, required duration of follow-up and extent of research nurse support required. Data were also used to inform the cost-effectiveness and value of information analyses, which were conducted alongside the pilot trial. Trial registration Current Controlled Trials ISRCTN69032034.

INVESTIGATING SUSPENSION OF MST SLURRIES IN A PILOT-SCALE WASTE TANK

Energy Technology Data Exchange (ETDEWEB)

Poirier, M.; Restivo, M.; Steeper, T.; Williams, M.; Qureshi, Z.

2011-01-24

The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for suspending monosodium titanate (MST), crystalline silicotitanate (CST), and simulated sludge. The purpose of this pilot scale testing is for the pumps to suspend the MST particles so that MST can be removed from the tank. The pilot-scale tank is a 1/10.85 linear scaled model of Tank 41H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 41H. The pump locations correspond to the proposed locations in Tank 41H by the SCIX program (Risers B5 and B2 for two pump configurations and Risers B5, B3, and B1 for three pump configurations).

Indices of language outcome 11 years after intrathecal chemotherapy for acute lymphoblastic leukemia: a sibling case-control study.

Science.gov (United States)

Lewis, Fiona M; Su, I-Fan; Murdoch, Bruce E

2012-03-01

Studies are emerging that suggest that major language indices do not differentiate children treated for acute lymphoblastic leukemia (ALL) with risk-adapted intrathecal chemotherapy (ITC) from control children matched on age, gender, and educational level. No study to date has controlled for cognitive environment, an important variable influencing language achievement and outcome. This case-control study applies the deconfounding principle by using a sibling as a control to investigate language outcomes in a male child 11 years after administration of ITC for ALL at the age of 2 years 3 months. A comprehensive behavioral language test battery failed to differentiate the siblings on current language performance when descriptively compared, but neurophysiological assessment revealed that the ITC-treated child required more time and elicited a smaller N400 component compared to his sibling during picture-word matching. The findings suggest that in the absence of pretreatment performance indices, comparison with sibling achievement may supplement what is known on posttreatment language skill development drawn from comparative studies using children matched on age, sex, and educational level drawn from the community. The study's findings offer pilot data of language outcomes following ITC beyond the early stage of survivorship. The benefits and limitations of using siblings in research where the cognitive environment is known to make an important contribution to skill development are discussed.

Prediction of pilot opinion ratings using an optimal pilot model. [of aircraft handling qualities in multiaxis tasks

Science.gov (United States)

Hess, R. A.

1977-01-01

A brief review of some of the more pertinent applications of analytical pilot models to the prediction of aircraft handling qualities is undertaken. The relative ease with which multiloop piloting tasks can be modeled via the optimal control formulation makes the use of optimal pilot models particularly attractive for handling qualities research. To this end, a rating hypothesis is introduced which relates the numerical pilot opinion rating assigned to a particular vehicle and task to the numerical value of the index of performance resulting from an optimal pilot modeling procedure as applied to that vehicle and task. This hypothesis is tested using data from piloted simulations and is shown to be reasonable. An example concerning a helicopter landing approach is introduced to outline the predictive capability of the rating hypothesis in multiaxis piloting tasks.

Role of U.S. animal control agencies in equine neglect, cruelty, and abandonment investigations.

Science.gov (United States)

Stull, C L; Holcomb, K E

2014-05-01

Every state in the United States has regulations prohibiting acts of neglect and cruelty against animals. Local law enforcement and animal control agencies are responsible in many communities to enforce these statutes. As society's perception of horses has changed from their origin as livestock to companion animals in modern times, owners have transitioned their care and management. The goal of this study was to identify the role and capacities of local animal control services in the United States that investigate equine neglect, cruelty, and abandonment investigations and to identify challenges and outcomes of the investigations. A 128-question online survey was accessible for animal agencies to complete. Comprehensive questions included their capacity for investigating equine cases, funding, housing for horses, and causes and outcomes of investigations. Respondents also were asked to select a single case and provide detailed information on the condition of horses, seizure and custody procedures, costs, and prosecution proceedings. A total of 165 respondents from 26 states completed all or the majority of the questions. A total of 6,864 equine investigations were initiated between 2007 and 2009 by 90 agencies, which extrapolates to 38 investigations annually per agency. A typical agency has an average annual budget of $740,000, employs 7 animal control officers, and spends about $10,000 annually on equine cases. Neglect was ranked as the most common reason for investigation. Owner ignorance, economic hardship, and lack of responsibility were the highest ranked causes of neglect and cruelty. Individual cases were provided by 91 agencies concerning 749 equines. The physical condition of the horse was the primary factor of investigation, and low body condition, parasite infestation, and compromised dental condition were present in most seized horses. Over half of the equine owners previously had been investigated or charged with neglect or cruelty of animals or were

EFFECT OF NEBULIZED COLISTIN ON THE VENTILATOR CIRCUIT: A PROSPECTIVE PILOT CASE-CONTROL STUDY FROM A SINGLE CANCER CENTER

Directory of Open Access Journals (Sweden)

Iyad M Ghonimat

2015-04-01

Full Text Available Nebulized colistin (NC is used for the treatment of pneumonia due to multidrug-resistant Gram-negative bacteria. In this one-year case-control study, our objective was to evaluate the effect of NC on the ventilator circuit (VC components. The case group consisted of 25 mechanically-ventilated patients who received NC, while the control group was 25 mechanically-ventilated patients who did not receive NC. Respiratory therapists inspected the VC every 4 hrs and whenever a ventilator alarm was reported. The VC component was changed if the alarm did not subside after necessary measures were performed. Patients from both groups were treated at the adult ICU in King Hussein Cancer Center (KHCC. In the case group, 22(88% patients required changing at least one of the circuit components (flow sensor, exhalation membrane, or nebulizer kit. The median number of changes (range per patient of the flow sensor, exhalation membrane, and nebulizer kit were: 2(1-3, 2(1-6, and 1(1-2, respectively. Large amounts of white crystals, which resembled the colistin powder, were reported on the replaced VC components. The flow sensor was changed in 2 control patients, but white crystals were absent. Crystals obtained from one case subject were confirmed to be colistin by chromatographic mass spectroscopy. Further studies are needed to evaluate the effect of crystal formation on the efficacy of NC and clinical outcomes.

Computer-Based Cognitive Training for Mild Cognitive Impairment: Results from a Pilot Randomized, Controlled Trial

OpenAIRE

Barnes, Deborah E.; Yaffe, Kristine; Belfor, Nataliya; Jagust, William J.; DeCarli, Charles; Reed, Bruce R.; Kramer, Joel H.

2009-01-01

We performed a pilot randomized, controlled trial of intensive, computer-based cognitive training in 47 subjects with mild cognitive impairment (MCI). The intervention group performed exercises specifically designed to improve auditory processing speed and accuracy for 100 minutes/day, 5 days/week for 6 weeks; the control group performed more passive computer activities (reading, listening, visuospatial game) for similar amounts of time. Subjects had a mean age of 74 years and 60% were men; 7...

Case–control study of HLA-G promoter methylation status, HPV infection and cervical neoplasia in Curitiba, Brazil: a pilot analysis

International Nuclear Information System (INIS)

Gillio-Tos, Anna; Carvalho, Newton S; Maestri, Carlos A; Lacerda, Hadriano M; Zugna, Daniela; Richiardi, Lorenzo; Merletti, Franco; Bicalho, Maria da Graça; Fiano, Valentina; Grasso, Chiara; Tarallo, Valentina; De Marco, Laura; Trevisan, Morena; Xavier, MarinaBarbaradeSousa; Slowik, Renata

2012-01-01

The causal association between persistent human papillomavirus (HPV) infection and cervical cancer has been established, but the mechanisms that favor HPV persistence in cervical cells are still unknown. The diminished capability of the immune system to control and resolve HPV infection is one of several hypotheses. The tolerogenic protein HLA-G has shown aberrant expression in a variety of cancers, which has been suggested as a mechanism for tumor escape from immunosurveillance. In the present study we evaluate the role of epigenetic modification (promoter de-methylation) of the HLA-G gene on susceptibility to HPV infection and development of high-grade cervical lesions. A case–control study was carried out in Curitiba, Brazil, between February and June 2010. A total of 789 women aged 15–47 years were recruited: 510 controls with normal cervical cytology, and 279 cases with histologically confirmed cervical intraepithelial neoplasia grade 2 (CIN2, N = 150) or grade 3 (CIN3, N = 129). All women were administered a questionnaire by interview, which collected information on demographic and lifestyle factors, and a cervical sample was collected. HPV DNA detection was performed by GP5+/GP6+ primer-mediated PCR. HPV-positive samples were genotyped by multiplex PCR. A pilot analysis of HLA-G promoter methylation was carried out in a subset of the study population (96 cases and 76 controls) by pyrosequencing. HLA-G methylation and HPV infection status of cases and controls were compared, and confounding factors were computed by t Student and non-parametric Wilcoxon tests. Comparison of HLA-G methylation between cases and controls was assessed by the Bonferroni correction. The association of HLA-G methylation with CIN2/3 was evaluated by logistic regression. HPV prevalence was 19.6% in controls and 94.3% in CIN2/3 cases. HPV16, 31, 33, 35 and 18 were the most prevalent types. Methylation analysis of seven CpGs in the HLA-G promoter did not reveal any spontaneous de

A pilot audit of a protocol for ambulatory investigation of predicted low-risk patients with possible pulmonary embolism.

Science.gov (United States)

McDonald, A H; Murphy, R

2011-09-01

Patients with possible pulmonary embolism (PE) commonly present to acute medical services. Research has led to the identification of low-risk patients suitable for ambulatory management. We report on a protocol designed to select low-risk patients for ambulatory investigation if confirmatory imaging is not available that day. The protocol was piloted in the Emergency Department and Medical Assessment Area at the Royal Infirmary of Edinburgh. We retrospectively analysed electronic patient records in an open observational audit of all patients managed in the ambulatory arm over five months of use. We analysed 45 patients' records. Of these, 91.1% required imaging to confirm or refute PE, 62.2% received a computed tomography pulmonary angiogram (CTPA). In 25% of patients, PE was confirmed with musculoskeletal pain (22.7%), and respiratory tract infection (15.9%) the next most prevalent diagnoses. Alternative diagnoses was provided by CTPA in 32% of cases. We identified no adverse events or readmissions but individualised follow-up was not attempted. The data from this audit suggests this protocol can be applied to select and manage low-risk patients suitable for ambulatory investigation of possible PE. A larger prospective comparative study would be required to accurately define the safety and effectiveness of this protocol.

Effects of continuous positive airway pressure on energy intake in obstructive sleep apnea: A pilot sham-controlled study

Science.gov (United States)

Shechter, Ari; Kovtun, Kyle; St-Onge, Marie-Pierre

2016-01-01

Obesity is among the leading risk factors for obstructive sleep apnea (OSA). A reciprocal relationship between obesity and OSA has been proposed, which may be due to excessive food intake. We conducted a pilot study to test the effects of continuous positive airway pressure (CPAP) on energy intake (EI) in OSA patients using a sham-controlled crossover design. In-laboratory total daily EI was assessed after 2 mo of active and sham CPAP. Four men were enrolled (age ± SEM: 51.8 ± 2.1 y; body mass index: 31.5 ± 1.5 kg/m2). All received active treatment first. Meals (breakfast, lunch, dinner, snack) were served in excess portions at fixed times and additional palatable snacks were freely available throughout the day. Total EI was lower after active (3744 ± 511 kcal/d) vs. sham (4030 ± 456 kcal/d) CPAP but this difference was not significant (p = 0.51) due to variability in the free snack intake. When only fixed eating occasions were considered, daily EI was significantly lower in the active (3105 ± 513 kcal/d) vs. sham (3559 ± 420 kcal/d) condition (p = 0.006). This small pilot and feasibility study is the first to utilize a sham-controlled design to investigate the effects of CPAP treatment on objective measures of EI. Findings suggest that CPAP may cause a reduction in fixed meal intake. In demonstrating feasibility of study methodology, our study also suggests a larger randomized sham-controlled trial be conducted to fully characterize the effects of CPAP treatment on EI and energy balance overall. PMID:27769851

Pre-Study Walkthrough with a Commercial Pilot for a Preliminary Single Pilot Operations Experiment

Science.gov (United States)

O'Connor-Dreher, Ryan; Roberts, Z.; Ziccardi, J.; Vu, K-P. L.; Strybel, T.; Koteskey, Robert William; Lachter, Joel B.; Vi Dao, Quang; Johnson, Walter W.; Battiste, V.

2013-01-01

The number of crew members in commercial flights has decreased to two members, down from the five-member crew required 50 years ago. One question of interest is whether the crew should be reduced to one pilot. In order to determine the critical factors involved in safely transitioning to a single pilot, research must examine whether any performance deficits arise with the loss of a crew member. With a concrete understanding of the cognitive and behavioral role of a co-pilot, aeronautical technologies and procedures can be developed that make up for the removal of the second aircrew member. The current project describes a pre-study walkthrough process that can be used to help in the development of scenarios for testing future concepts and technologies for single pilot operations. Qualitative information regarding the tasks performed by the pilots can be extracted with this technique and adapted for future investigations of single pilot operations.

Practical Implications of Metacognitively Oriented Psychotherapy in Psychosis : Findings From a Pilot Study

NARCIS (Netherlands)

de Jong, Steven; van Donkersgoed, Rozanne J. M.; Aleman, Andre; van der Gaag, Mark; Wunderink, Lex; Arends, Johan; Lysaker, Paul H.; Pijnenborg, Marieke

In preparation for a multicenter randomized controlled trial, a pilot study was conducted investigating the feasibility and acceptance of a shortened version (12 vs. 40 sessions) of an individual metacognitive psychotherapy (Metacognitive Reflection and Insight Therapy [MERIT]). Twelve participants

A pilot investigation to optimise methods for a future satiety preload study.

Science.gov (United States)

Hobden, Mark R; Guérin-Deremaux, Laetitia; Commane, Daniel M; Rowland, Ian; Gibson, Glenn R; Kennedy, Orla B

2017-01-01

Preload studies are used to investigate the satiating effects of foods and food ingredients. However, the design of preload studies is complex, with many methodological considerations influencing appetite responses. The aim of this pilot investigation was to determine acceptability, and optimise methods, for a future satiety preload study. Specifically, we investigated the effects of altering (i) energy intake at a standardised breakfast (gender-specific or non-gender specific), and (ii) the duration between mid-morning preload and ad libitum lunch meal, on morning appetite scores and energy intake at lunch. Participants attended a single study visit. Female participants consumed a 214-kcal breakfast ( n  = 10) or 266-kcal breakfast ( n  = 10), equivalent to 10% of recommended daily energy intakes for females and males, respectively. Male participants ( n  = 20) consumed a 266-kcal breakfast. All participants received a 250-ml orange juice preload 2 h after breakfast. The impact of different study timings was evaluated in male participants, with 10 males following one protocol (protocol 1) and 10 males following another (protocol 2). The duration between preload and ad libitum lunch meal was 2 h (protocol 1) or 2.5 h (protocol 2), with the ad libitum lunch meal provided at 12.00 or 13.00, respectively. All female participants followed protocol 2. Visual analogue scale (VAS) questionnaires were used to assess appetite responses and food/drink palatability. Correlation between male and female appetite scores was higher with the provision of a gender-specific breakfast, compared to non-gender-specific breakfast (Pearson correlation of 0.747 and 0.479, respectively). No differences in subjective appetite or ad libitum energy intake were found between protocols 1 and 2. VAS mean ratings of liking, enjoyment, and palatability were all > 66 out of 100 mm for breakfast, preload, and lunch meals. The findings of this pilot study confirm the acceptability

Idiopathic Syringomyelia in a Military Helicopter Pilot.

Science.gov (United States)

Schiemer, Anthony

2017-10-01

A syrinx is a fluid-filled cavity within the spinal cord. They can lead to a variety of symptoms, including limb weakness and back pain. Incidental finding of syringomyelia provides a challenge for clinicians due to the wide variety of possible symptoms. In military aviation, neurological findings in pilots can result in extensive investigation that can lead to potentially invasive management. Conversely, the potential for chronic progression of a spinal syrinx and subsequent neurological deterioration makes early identification critical. Ultimately, the discovery of a lesion may have implications for flying status and operational capability. A 25-yr-old man working as a navy Seahawk helicopter pilot presented with episodes of right arm paraesthesia and pain between the scapulae. On at least one occasion, these symptoms woke him at night. Upon magnetic resonance imaging, dilatation of the central canal in a syrinx-like pattern in the lower cervical region was noted. Neurology review suggested the finding was persistent and unlikely to be responsible for his symptoms. No surgical input was recommended. His symptoms were attributed to mild cervical spondylosis, which resolved with ongoing physiotherapy, and he was returned to flying status. This case highlights several issues involved with the incidental finding of a syringomyelia. Surgical intervention has been known to worsen symptoms. Conversely, studies have identified minimal radiological progression in cases of idiopathic syringomyelia, with fewer individuals displaying neurological deterioration. For aircrew, potentially unnecessary neurosurgical intervention poses risks to a flying career and overall operational capability.Schiemer A. Idiopathic syringomyelia in a military helicopter pilot. Aerosp Med Hum Perform. 2017; 88(10):962-965.

Managerial span of control: a pilot study comparing departmental complexity and number of direct reports.

Science.gov (United States)

Merrill, Katreena Collette; Pepper, Ginette; Blegen, Mary

2013-09-01

Nurse managers play pivotal roles in hospitals. However, restructuring has resulted in nurse managers having wider span of control and reduced visibility. The purpose of this pilot study was to compare two methods of measuring span of control: departmental complexity and number of direct reports. Forty-one nurse managers across nine hospitals completed The Ottawa Hospital Clinical Manager Span of Control Tool (TOH-SOC) and a demographic survey. A moderate positive relationship between number of direct reports and departmental complexity score was identified (r=.49, p=managers' responsibility. Copyright © 2013 Longwoods Publishing.

Flight Investigation of the Low-Speed Characteristics of a 45 deg Swept-Wing Fighter-Type Airplane with Blowing Boundary-Layer Control Applied to the Leading- and Trailing-Edge Flaps

Science.gov (United States)

Quigley, Hervey C.; Anderson, Seth B.; Innis, Robert C.

1960-01-01

A flight investigation has been conducted to study how pilots use the high lift available with blowing-type boundary-layer control applied to the leading- and trailing-edge flaps of a 45 deg. swept-wing airplane. The study includes documentation of the low-speed handling qualities as well as the pilots' evaluations of the landing-approach characteristics. All the pilots who flew the airplane considered it more comfortable to fly at low speeds than any other F-100 configuration they had flown. The major improvements noted were the reduced stall speed, the improved longitudinal stability at high lift, and the reduction in low-speed buffet. The study has shown the minimum comfortable landing-approach speeds are between 120.5 and 126.5 knots compared to 134 for the airplane with a slatted leading edge and the same trailing-edge flap. The limiting factors in the pilots' choices of landing-approach speeds were the limits of ability to control flight-path angle, lack of visibility, trim change with thrust, low static directional stability, and sluggish longitudinal control. Several of these factors were found to be associated with the high angles of attack, between 13 deg. and 15 deg., required for the low approach speeds. The angle of attack for maximum lift coefficient was 28 deg.

Exercise training as treatment of neck pain among fighter pilots

DEFF Research Database (Denmark)

Murray, Mike; Lange, Britt; Andersen, Christoffer Højnicke

) seldom, trained but stopped, 6) no participation at all. Maximal Voluntary Isometric Contraction (MVC) and Rate of Force Development (RFD) for cervical flexion and extension were measured by strain-gauge transducers. Results Prevalence of neck pain was significantly reduced in ET from baseline (mean ± SD......Introduction Neck and shoulder pain is a common complaint among fighter pilots and a growing aero-medical concern. Unfortunately, previous intervention studies have been unsuccessful in relieving such pain within this occupational group. The aim of this study was to investigate if an exercise...... intervention could reduce the high prevalence of neck pain among fighter pilots. Methods F-16 pilots were randomized in a controlled intervention trial, to either an exercise-training-group (ET, n=27) or reference-group (REF, n=28). ET underwent 24 weeks of strength, endurance, and coordination training, 3...

Are pilot trials useful for predicting randomisation and attrition rates in definitive studies: A review of publicly funded trials

Science.gov (United States)

Whitehead, Amy; Pottrill, Edward; Julious, Steven A; Walters, Stephen J

2018-01-01

Background/aims: External pilot trials are recommended for testing the feasibility of main or confirmatory trials. However, there is little evidence that progress in external pilot trials actually predicts randomisation and attrition rates in the main trial. To assess the use of external pilot trials in trial design, we compared randomisation and attrition rates in publicly funded randomised controlled trials with rates in their pilots. Methods: Randomised controlled trials for which there was an external pilot trial were identified from reports published between 2004 and 2013 in the Health Technology Assessment Journal. Data were extracted from published papers, protocols and reports. Bland–Altman plots and descriptive statistics were used to investigate the agreement of randomisation and attrition rates between the full and external pilot trials. Results: Of 561 reports, 41 were randomised controlled trials with pilot trials and 16 met criteria for a pilot trial with sufficient data. Mean attrition and randomisation rates were 21.1% and 50.4%, respectively, in the pilot trials and 16.8% and 65.2% in the main. There was minimal bias in the pilot trial when predicting the main trial attrition and randomisation rate. However, the variation was large: the mean difference in the attrition rate between the pilot and main trial was −4.4% with limits of agreement of −37.1% to 28.2%. Limits of agreement for randomisation rates were −47.8% to 77.5%. Conclusion: Results from external pilot trials to estimate randomisation and attrition rates should be used with caution as comparison of the difference in the rates between pilots and their associated full trial demonstrates high variability. We suggest using internal pilot trials wherever appropriate. PMID:29361833

Field-based random sampling without a sampling frame: control selection for a case-control study in rural Africa.

Science.gov (United States)

Crampin, A C; Mwinuka, V; Malema, S S; Glynn, J R; Fine, P E

2001-01-01

Selection bias, particularly of controls, is common in case-control studies and may materially affect the results. Methods of control selection should be tailored both for the risk factors and disease under investigation and for the population being studied. We present here a control selection method devised for a case-control study of tuberculosis in rural Africa (Karonga, northern Malawi) that selects an age/sex frequency-matched random sample of the population, with a geographical distribution in proportion to the population density. We also present an audit of the selection process, and discuss the potential of this method in other settings.

Silicon-controlled rectifier failure investigation report, April 11 and May 7, 1986, Type A occurrence

International Nuclear Information System (INIS)

1986-01-01

As a result of the April 11, 1986 failure and subsequent property damage of the silicon-controlled rectifier (SCR) device used to provide dc power to the motor driven construction and salt handling (CandSH) hoist at the Waste Isolation Pilot Plant (WIPP), the Project Manager, WIPP Project Office, appointed an Accident Investigation Board on April 14, 1986. The Board was tasked to investigate, to determine the cause or causes of the SCR failure, and to make appropriate recommendations to prevent a recurrence. Subsequently, the scope of the investigation was expanded on April 22, 1986, to include a series of failures that occurred after the initial failure. This occurrence came after the SCR had been released by the Board, repaired, modified, and returned to use. The investigation included a review of the engineering, procurement, operations, and maintenance programs of the Management and Operating Contractor (MOC), along with a detailed investigation of the hardware involved in the failure. Analytical techniques included use of the Management Oversight Risk Tree (MORT) and Events and Causal Factors Sequence Charting. 15 figs

An in-flight investigation of pilot-induced oscillation suppression filters during the fighter approach and landing task

Science.gov (United States)

Bailey, R. E.; Smith, R. E.

1982-01-01

An investigation of pilot-induced oscillation suppression (PIOS) filters was performed using the USAF/Flight Dynamics Laboratory variable stability NT-33 aircraft, modified and operated by Calspan. This program examined the effects of PIOS filtering on the longitudinal flying qualities of fighter aircraft during the visual approach and landing task. Forty evaluations were flown to test the effects of different PIOS filters. Although detailed analyses were not undertaken, the results indicate that PIOS filtering can improve the flying qualities of an otherwise unacceptable aircraft configuration (Level 3 flying qualities). However, the ability of the filters to suppress pilot-induced oscillations appears to be dependent upon the aircraft configuration characteristics. Further, the data show that the filters can adversely affect landing flying qualities if improperly designed. The data provide an excellent foundation from which detail analyses can be performed.

Massage therapy and exercise therapy in patients with multiple sclerosis: a randomized controlled pilot study.

Science.gov (United States)

Negahban, Hossein; Rezaie, Solmaz; Goharpey, Shahin

2013-12-01

The primary aim was to investigate the comparative effects of massage therapy and exercise therapy on patients with multiple sclerosis. The secondary aim was to investigate whether combination of both massage and exercise has an additive effect. Randomized controlled pilot trial with repeated measurements and blinded assessments. Local Multiple Sclerosis Society. A total of 48 patients with multiple sclerosis were randomly assigned to four equal subgroups labelled as massage therapy, exercise therapy, combined massage-exercise therapy and control group. The treatment group received 15 sessions of supervised intervention for five weeks. The massage therapy group received a standard Swedish massage. The exercise therapy group was given a combined set of strength, stretch, endurance and balance exercises. Patients in the massage-exercise therapy received a combined set of massage and exercise treatments. Patients in the control group were asked to continue their standard medical care. Pain, fatigue, spasticity, balance, gait and quality of life were assessed before and after intervention. Massage therapy resulted in significantly larger improvement in pain reduction (mean change 2.75 points, P = 0.001), dynamic balance (mean change, 3.69 seconds, P = 0.009) and walking speed (mean change, 7.84 seconds, P = 0.007) than exercise therapy. Patients involved in the combined massage-exercise therapy showed significantly larger improvement in pain reduction than those in the exercise therapy (mean change, 1.67 points, P = 0.001). Massage therapy could be more effective than exercise therapy. Moreover, the combination of massage and exercise therapy may be a little more effective than exercise therapy alone.

Ho:YAG laser in reshaping tracheal cartilage: a pilot investigation using ex vivo porcine and rabbit cartilage

Science.gov (United States)

Lam, Anthony; Protsenko, Dmitry E.; Carbone, Nicholas; Li, Chao; Jackson, Ryan; Wong, Brian J.

2004-07-01

Stenotic, collapsed, and flow-restricted tracheal airways may result from blunt trauma, chronic infection, and the prolonged endotracheal intubation. This pilot investigation characterizes the degree of shape change produced by Ho:YAG laser (λ=2.12 μm) irradiation of rabbit and pig trachea tissue as a function of laser dosimetry and application protocol. Force displacement curves were generated using fresh lagomorph and porcine tracheal cartilage rings secured in a modified single beam cantilever geometry. These specimens were then irradiated for varying amounts of time and power with the objective of straightening these curved specimens. The degree of shape change was documented photographically. Force and surface temperature were monitored. Confocal microscopy was then used in combination a vital staine ("live-dead assay") to determine the level of viability of straightened cartilage for selected exposure time-power pairs. Laser Cartilage Reshaping of the trachea may provide a new method to treat severe tracheal injuries without the need for classic open surgical techniques. This pilot investigation is the first step toward demonstrating the feasibility of this technique. Long-term, the design of stents combined with laser irradiation may provide a means to alter tracheal shape.

Pilot Preference, Compliance, and Performance With an Airborne Conflict Management Toolset

Science.gov (United States)

Doble, Nathan A.; Barhydt, Richard; Krishnamurthy, Karthik

2005-01-01

A human-in-the-loop experiment was conducted at the NASA Ames and Langley Research Centers, investigating the En Route Free Maneuvering component of a future air traffic management concept termed Distributed Air/Ground Traffic Management (DAG-TM). NASA Langley test subject pilots used the Autonomous Operations Planner (AOP) airborne toolset to detect and resolve traffic conflicts, interacting with subject pilots and air traffic controllers at NASA Ames. Experimental results are presented, focusing on conflict resolution maneuver choices, AOP resolution guidance acceptability, and performance metrics. Based on these results, suggestions are made to further improve the AOP interface and functionality.

DIRAC universal pilots

Science.gov (United States)

Stagni, F.; McNab, A.; Luzzi, C.; Krzemien, W.; Consortium, DIRAC

2017-10-01

In the last few years, new types of computing models, such as IAAS (Infrastructure as a Service) and IAAC (Infrastructure as a Client), gained popularity. New resources may come as part of pledged resources, while others are in the form of opportunistic ones. Most but not all of these new infrastructures are based on virtualization techniques. In addition, some of them, present opportunities for multi-processor computing slots to the users. Virtual Organizations are therefore facing heterogeneity of the available resources and the use of an Interware software like DIRAC to provide the transparent, uniform interface has become essential. The transparent access to the underlying resources is realized by implementing the pilot model. DIRAC’s newest generation of generic pilots (the so-called Pilots 2.0) are the “pilots for all the skies”, and have been successfully released in production more than a year ago. They use a plugin mechanism that makes them easily adaptable. Pilots 2.0 have been used for fetching and running jobs on every type of resource, being it a Worker Node (WN) behind a CREAM/ARC/HTCondor/DIRAC Computing element, a Virtual Machine running on IaaC infrastructures like Vac or BOINC, on IaaS cloud resources managed by Vcycle, the LHCb High Level Trigger farm nodes, and any type of opportunistic computing resource. Make a machine a “Pilot Machine”, and all diversities between them will disappear. This contribution describes how pilots are made suitable for different resources, and the recent steps taken towards a fully unified framework, including monitoring. Also, the cases of multi-processor computing slots either on real or virtual machines, with the whole node or a partition of it, is discussed.

Results of pilot project on introducing quality control of mammographic equipment

International Nuclear Information System (INIS)

Vasileva, Zh.; Lichev, A.; Dimov, A.; Kostova, E.; Dimov, G.

2003-01-01

Objective:The results from a pilot project, realized in the framework of the PHARE Project 'Radiation Protection and Safety in Medical Use of the Ionizing Radiation'. The main goal of the project is the elaboration a quality control program for mammographic equipment and its implementation in 4 radiological units in the country. Another task is to examine the possibility for conducting a mammographic screening using this equipment. Material and methods: The developed quality control program has the following components: test parameters; criteria for intervention; minimal frequency of measurement. Methodologies for measurement of the parameters and assessment of the results in accordance with the European Protocol for physical and technical aspects of the mammographic screening. Standard protocols have been elaborated. Results: The quality program has been tested for three month at different hospitals. Conclusions: Optimization and strict control of the process of film development are needed. The exposure equipment. The quality control program should be implemented on all mammographic equipment in the country. For the performance of mammographic screening a strict selection of the equipment is necessary

Pilot-in-the-Loop Evaluation of a Yaw Rate to Throttle Feedback Control with Enhanced Engine Response

Science.gov (United States)

Litt, Jonathan S.; Guo, Ten-Huei; Sowers, T. Shane; Chicatelli, Amy K.; Fulton, Christopher E.; May, Ryan D.; Owen, A. Karl

2012-01-01

This paper describes the implementation and evaluation of a yaw rate to throttle feedback system designed to replace a damaged rudder. It can act as a Dutch roll damper and as a means to facilitate pilot input for crosswind landings. Enhanced propulsion control modes were implemented to increase responsiveness and thrust level of the engine, which impact flight dynamics and performance. Piloted evaluations were performed to determine the capability of the engines to substitute for the rudder function under emergency conditions. The results showed that this type of implementation is beneficial, but the engines' capability to replace the rudder is limited.

Pilot studies of management of ageing of nuclear power plant instrumentation and control components

International Nuclear Information System (INIS)

Burnay, S.G.; Simola, K.; Kossilov, A.; Pachner, J.

1993-01-01

This paper describes pilot studies which have been implemented to study the aging behavior of safety related component parts of nuclear power plants. In 1989 the IAEA initiated work on pilot studies related to the aging of such components. Four components were identified for study. They are the primary nozzle of a reactor vessel; a motor operated isolating valve; the concrete containment building; and instrumentation and control cables within the containment facility. The study was begun with phase 1 efforts directed toward understanding the aging process, and methods for monitoring and minimizing the effects of aging. Phase 2 efforts are directed toward aging studies, documentation of the ideas put forward, and research to answer questions identified in phase 1. This paper describes progress made on two of these components, namely the motor operated isolation valves, and in-containment I ampersand C cables

The policy work of piloting: Mobilising and managing conflict and ambiguity in the English NHS.

Science.gov (United States)

Bailey, Simon; Checkland, Kath; Hodgson, Damian; McBride, Anne; Elvey, Rebecca; Parkin, Stephen; Rothwell, Katy; Pierides, Dean

2017-04-01

In spite of their widespread use in policy making in the UK and elsewhere, there is a relatively sparse literature specifically devoted to policy pilots. Recent research on policy piloting has focused on the role of pilots in making policy work in accordance with national agendas. Taking this as a point of departure, the present paper develops the notion of pilots doing policy work. It does this by situating piloting within established theories of policy formulation and implementation, and illustrating using an empirical case. Our case is drawn from a qualitative policy ethnography of a local government pilot programme aiming to extend access to healthcare services. Our case explores the collective entrepreneurship of regional policy makers together with local pilot volunteers. We argue that pilots work to mobilise and manage the ambiguity and conflict associated with particular policy goals, and in their structure and design, shape action towards particular outcomes. We conclude with a discussion of the generative but managed role which piloting affords to local implementers. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

In-Flight Validation of a Pilot Rating Scale for Evaluating Failure Transients in Electronic Flight Control Systems

Science.gov (United States)

Kalinowski, Kevin F.; Tucker, George E.; Moralez, Ernesto, III

2006-01-01

Engineering development and qualification of a Research Flight Control System (RFCS) for the Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) JUH-60A has motivated the development of a pilot rating scale for evaluating failure transients in fly-by-wire flight control systems. The RASCAL RFCS includes a highly-reliable, dual-channel Servo Control Unit (SCU) to command and monitor the performance of the fly-by-wire actuators and protect against the effects of erroneous commands from the flexible, but single-thread Flight Control Computer. During the design phase of the RFCS, two piloted simulations were conducted on the Ames Research Center Vertical Motion Simulator (VMS) to help define the required performance characteristics of the safety monitoring algorithms in the SCU. Simulated failures, including hard-over and slow-over commands, were injected into the command path, and the aircraft response and safety monitor performance were evaluated. A subjective Failure/Recovery Rating (F/RR) scale was developed as a means of quantifying the effects of the injected failures on the aircraft state and the degree of pilot effort required to safely recover the aircraft. A brief evaluation of the rating scale was also conducted on the Army/NASA CH-47B variable stability helicopter to confirm that the rating scale was likely to be equally applicable to in-flight evaluations. Following the initial research flight qualification of the RFCS in 2002, a flight test effort was begun to validate the performance of the safety monitors and to validate their design for the safe conduct of research flight testing. Simulated failures were injected into the SCU, and the F/RR scale was applied to assess the results. The results validate the performance of the monitors, and indicate that the Failure/Recovery Rating scale is a very useful tool for evaluating failure transients in fly-by-wire flight control systems.

Summary of scientific investigations for the Waste Isolation Pilot Plant

International Nuclear Information System (INIS)

Weart, W.D.

1996-01-01

The scientific issues concerning disposal of radioactive wastes in salt formations have received 40 years of attention since the National Academy of Sciences (NAS) first addressed this issue in the mid-50s. For the last 21 years, Sandia National Laboratories (SNL) have directed site specific studies for the Waste Isolation Pilot Plant (WIPP). This paper will focus primarily on the WIPP scientific studies now in their concluding stages, the major scientific controversies regarding the site, and some of the surprises encountered during the course of these scientific investigations. The WIPP project's present understanding of the scientific processes involved continues to support the site as a satisfactory, safe location for the disposal of defense-related transuranic waste and one which will be shown to be in compliance with Environmental Protection Agency (EPA) standards. Compliance will be evaluated by incorporating data from these experiments into Performance Assessment (PA) models developed to describe the physical and chemical processes that could occur at the WIPP during the next 10,000 years under a variety of scenarios. The resulting compliance document is scheduled to be presented to the EPA in October 1996 and all relevant information from scientific studies will be included in this application and the supporting analyses. Studies supporting this compliance application conclude the major period of scientific investigation for the WIPP. Further studies will be of a ''confirmatory'' and monitoring nature

Investigation on the use digital controls instead of PID analog controls in the level control of steam generators of nuclear power PWR

International Nuclear Information System (INIS)

Alvarenga, Marco Antonio Bayout

2012-01-01

The aim of this study is to identify current alternatives for the implementation of digital controllers in the level control of steam generators of nuclear power PWR (Pressurized Water Reaetor). It is intended to identify the types of digital controls that are available from the theoretical and conceptual viewpoints for this purpose. We investigate the advantages and disadvantages of each controller model. From this assessment are pointed the most suitable models in hierarchical scale. This evaluation also serves to suggest possible types of control installation as a whole, where the level control of the steam generators becomes just one of many controls that are part of the plant. In this case, the use of digital controls allows the non-linear and multivariable treatment which is characteristic of complex systems, such as the nuclear power generation. The treatment of nonlinearities and multivariable aspects allows a more detailed study of the stability of these plants when they are subject to transients or several accidents, such as the case of losing external power of transients. In the specific case of steam generators, the instabilities result from the emergence of the shrink and swell phenomenas, depending on the load variations of thermonuclear plant. The application of several types and digital controllers, considering these inherent characteristics of the level control of steam generators, allows to infer which types of controllers are more appropriate to treat instabilities of this type and to make conjectures in its use for the cases of more complex instabilities, considering the integration of all nucleus-plant controls.

Gaming and conventional exercises for improvement of arm function after stroke: a randomised controlled pilot study

NARCIS (Netherlands)

Kottink, A.I.R.; Prange, Grada Berendina; Krabben, T.; Rietman, Johan Swanik; Buurke, Jaap

2014-01-01

Objective: The use of new technologies in rehabilitation, such as virtual reality and/or computerized gaming exercises, may be useful to enable patients to practice intensively in a motivating way. The objective of the present randomized controlled pilot study was to compare the effect of reach

Manual and automatic flight control during severe turbulence penetration

Science.gov (United States)

Johnston, D. E.; Klein, R. H.; Hoh, R. H.

1976-01-01

An analytical and experimental investigation of possible contributing factors in jet aircraft turbulence upsets was conducted. Major contributing factors identified included autopilot and display deficiencies, the large aircraft inertia and associated long response time, and excessive pilot workload. An integrated flight and thrust energy management director system was synthesized. The system was incorporated in a moving-base simulation and evaluated using highly experienced airline pilots. The evaluation included comparison of pilot workload and flight performance during severe turbulence penetration utilizing four control/display concepts: manual control with conventional full panel display, conventional autopilot (A/P-A) with conventional full panel display, improved autopilot (A/P-B) with conventional full panel display plus thrust director display, and longitudinal flight director with conventional full panel display plus thrust director display. Simulation results show improved performance, reduced pilot workload, and a pilot preference for the autopilot system controlling to the flight director command and manual control of thrust following the trim thrust director.

Cross-sectional study of neck pain and cervical sagittal alignment in air force pilots.

Science.gov (United States)

Moon, Bong Ju; Choi, Kyong Ho; Yun, Chul; Ha, Yoon

2015-05-01

There is a high prevalence of neck pain in air force pilots; however, the causes are not clear and are considered work-related. Kyphotic changes in the cervical spine have been known to cause neck pain. In this study, we investigated the association between neck pain and cervical kyphosis in air force pilots. This is a cross-sectional study of 63 Republic of South Korea Air Force pilots. We examined the C2-7 absolute rotation angle (ARA) using the posterior tangent method and other radiologic parameters on whole spine lateral radiographs. We divided the participants into a neck pain group (N = 32) and no neck pain group (N = 31), and subsequently analyzed the difference in radiographic parameters and clinical data between the two groups. There were no significant differences found in age, body mass index, total flight time, or aerobic or anaerobic exercise between the neck pain and control groups. The fighter pilots had higher 1-yr prevalence of neck pain than nonfighter pilots (84.4% vs. 15.6%). The lower C2-7 ARA (OR = 0.91, 95% CI 0.846, 0.979) and fighter type aircrafts (OR = 3.93, 95% CI 1.104, 13.989) were associated with neck pain. Fighter pilots experienced neck pain more frequently than the nonfighter pilots. Those fighter pilots suffering from neck pain were shown to have more kyphotic changes in the cervical spine than control pilots through evaluation of whole spine lateral radiographs using the posterior tangent method. These key findings suggest that the forces involved in flying a fighter type aircraft may affect cervical alignment and neck pain.

Investigation and demonstration of dry carbon-based sorbent injection for mercury control. Quarterly technical report, July 1, 1996--September 31, 1996

Energy Technology Data Exchange (ETDEWEB)

Hunt, T.; Sjostrom, S.; Smith, J. [and others

1996-11-06

The overall objective of this two phase program is to investigate the use of dry carbon-based sorbents for mercury control. This information is important to the utility industry in anticipation of pending regulations. During Phase I, a bench-scale field test device that can be configured as an electrostatic precipitator, a pulse-jet baghouse, or a reverse-gas baghouse has been designed, built and integrated with an existing pilot-scale facility at PSCo`s Comanche Station. Up to three candidate sorbents will be injected into the flue gas stream upstream of the test device to and mercury concentration measurements will be made to determine the mercury removal efficiency for each sorbent. During the Phase II effort, component integration for the most promising dry sorbent technology shall be tested at the 5000 acfm pilot-scale.

An epidemiological investigation of the early phase of the porcine epidemic diarrhea (PED) outbreak in Canadian swine herds in 2014: A case-control study.

Science.gov (United States)

Perri, Amanda M; Poljak, Zvonimir; Dewey, Cate; Harding, John C S; O'Sullivan, Terri L

2018-02-01

The first case of porcine epidemic diarrhea (PED) in Canada was diagnosed in January 2014 in Ontario, approximately 9 months after PED emerged in the United States. An early investigation of the Canadian outbreak suspected that the probable source of the virus was contaminated feed. The objective of this study was to evaluate the role of feed and other possible factors in the early phase of the PED outbreak in Canadian swine herds. The study period of interest for this case-control study was January 22nd to March 1st, 2014. A case herd was defined as a swine herd with a confirmed positive laboratory diagnostic test (RT-PCR) results for PED virus, along with pigs exhibiting typical clinical signs at the herd level during the study period. A questionnaire was administered to participating producers from the 22 Canadian swine herds enrolled (n = 9 case and n = 13 control herds). Case herd producers were asked to provide information from the initial day of onset of clinical signs and 30 days prior to that day. Control herds were matched to a case herd on the basis of province, herd type and approximate size. The period of interest for a control herd was matched to the initial day of clinical signs of PED for the case herd, along with the 30 days prior to this day. The questionnaire questions focused on herd demographics, biosecurity protocols, live animal movements onto and off sites, deadstock movements, feed and people movements for both the case and control herds. The questionnaire for control herds were based on their matched case's period of interest, and together with case herds formed a matched stratum. Multivariable exact conditional logistic regression and mixed multivariable logistic regression models, with the matched stratum as a random effect, were used to assess the association between various risk factors and the odds of PED introduction into a herd. After adjusting for biosecurity practices, the odds of a PED occurrence was 38.1 (95% CI: 2

Intelligent Pilot Aids for Flight Re-Planning in Emergencies

Science.gov (United States)

Pritchett, Amy R.; Ockerman, Jennifer

2005-01-01

Effective and safe control of an aircraft may be difficult or nearly impossible for a pilot following an unexpected system failure. Without prior training, the pilot must ascertain on the fly those changes in both manual control technique and procedures that will lead to a safe landing of the aircraft. Sophisticated techniques for determining the required control techniques are now available. Likewise, a body of literature on pilot decision making provides formalisms for examining how pilots approach discrete decisions framed as the selection between options. However, other aspects of behavior, such as the task of route planning and guidance, are not as well studied. Not only is the pilot faced with possible performance changes to the aircraft dynamics, but he or she is also tasked to create a plan of actions that will effectively take the aircraft down to a safe landing. In this plan, the many actions that the pilot can perform are closely intertwined with the trajectory of the aircraft, making it difficult to accurately predict the final outcome. Coupled with the vast number of potential actions to be taken, this problem may seem intractable. This is reflected in the lack of a pre-specified procedure capable of giving pilots the ability to find a resolution for this task. This report summarizes a multi-year effort to examine methods to aid pilots in planning an approach and arrival to an airport following an aircraft systems failure. Ultimately, we hypothesize that automatic assistance to pilots can be provided in real-time in the form of improving pilot control of a damaged aircraft and providing pilots with procedural directives suitable for critical flight conditions; such systems may also benefit pilot training and procedure design. To achieve this result, a systematic, comprehensive research program was followed, building on prior research. This approach included a pencil-and-paper study with airline pilots examining methods of representing a flight route in

Advanced Instrumentation, Information and Control (II and C) Research and Development Facility Buildout and Project Execution of LWRS II and C Pilot Projects 1 and 3

International Nuclear Information System (INIS)

Farris, Ronald; Oxstrand, Johanna; Weatherby, Gregory

2011-01-01

The U.S. Department of Energy (DOE) is sponsoring research, development, and deployment on light water reactor sustainability (LWRS), in which the Idaho National Laboratory (INL) is working closely with nuclear utilities to develop technologies and solutions to help ensure the safe operational life extension of current reactors. As technologies are introduced that change the operation of the plant, the LWRS pilot projects can help identify their best-advanced uses and help demonstrate the safety of these technologies. In early testing of operator performance given these emerging technologies will ensure the safety and usability of systems prior to large-scale deployment and costly verification and validation at the plant. The aim of these collaborations, demonstrations, and approaches are intended to lessen the inertia that sustains the current status quo of today's II and C systems technology, and to motivate transformational change and a shift in strategy to a long-term approach to II and C modernization that is more sustainable. Research being conducted under Pilot Project 1 regards understanding the conditions and behaviors that can be modified, either through process improvements and/or technology deployment, to improve the overall safety and efficiency of outage control at nuclear facilities. The key component of the research in this pilot project is accessing the delivery of information that will allow researchers to simulate the control room, outage control center (OCC) information, and plant status data. The simulation also allows researchers to identify areas of opportunity where plant operating status and outage activities can be analyzed to increase overall plant efficiency. For Pilot Project 3 the desire is to demonstrate the ability of technology deployment and the subsequent impact on maximizing the 'Collective Situational Awareness' of the various stakeholders in a commercial nuclear power plant. Specifically, the desire is to show positive results

Energy extension service pilot program evaluation report: the first year. Volume II: pilot state reports

Energy Technology Data Exchange (ETDEWEB)

1979-09-01

Volume II of the Energy Extension Service Evaluation presents a discussion of the operations of the ten EES pilot-state programs during the period from October 1, 1977 through September 30, 1978. Each of the ten pilot states - Alabama, Connecticut, Michigan, New Mexico, Pennsylvania, Tennessee, Texas, Washington, Wisconsin, and Wyoming - received a grant of approximately $1.1 million to develop and implement a 19-month program beginning on October 1, 1977. Volume II provides a case-study description of the operations of the pilot program in each state, with special attention given to the two programs selected in each state for more detailed study and survey research. Some survey data and analysis are presented for the emphasis programs.

'Putting Life in Years' (PLINY) telephone friendship groups research study: pilot randomised controlled trial.

Science.gov (United States)

Mountain, Gail A; Hind, Daniel; Gossage-Worrall, Rebecca; Walters, Stephen J; Duncan, Rosie; Newbould, Louise; Rex, Saleema; Jones, Carys; Bowling, Ann; Cattan, Mima; Cairns, Angela; Cooper, Cindy; Edwards, Rhiannon Tudor; Goyder, Elizabeth C

2014-04-24

Loneliness in older people is associated with poor health-related quality of life (HRQoL). We undertook a parallel-group randomised controlled trial to evaluate the effectiveness and cost-effectiveness of telephone befriending for the maintenance of HRQoL in older people. An internal pilot tested the feasibility of the trial and intervention. Participants aged >74 years, with good cognitive function, living independently in one UK city were recruited through general practices and other sources, then randomised to: (1) 6 weeks of short one-to-one telephone calls, followed by 12 weeks of group telephone calls with up to six participants, led by a trained volunteer facilitator; or (2) a control group. The main trial required the recruitment of 248 participants in a 1-year accrual window, of whom 124 were to receive telephone befriending. The pilot specified three success criteria which had to be met in order to progress the main trial to completion: recruitment of 68 participants in 95 days; retention of 80% participants at 6 months; successful delivery of telephone befriending by local franchise of national charity. The primary clinical outcome was the Short Form (36) Health Instrument (SF-36) Mental Health (MH) dimension score collected by telephone 6 months following randomisation. We informed 9,579 older people about the study. Seventy consenting participants were randomised to the pilot in 95 days, with 56 (80%) providing valid primary outcome data (26 intervention, 30 control). Twenty-four participants randomly allocated to the research arm actually received telephone befriending due to poor recruitment and retention of volunteer facilitators. The trial was closed early as a result. The mean 6-month SF-36 MH scores were 78 (SD 18) and 71 (SD 21) for the intervention and control groups, respectively (mean difference, 7; 95% CI, -3 to 16). Recruitment and retention of participants to a definitive trial with a recruitment window of 1 year is feasible. For

Individual cognitive behavioral therapy for insomnia in breast cancer survivors: a randomized controlled crossover pilot study

Science.gov (United States)

Fiorentino, Lavinia; McQuaid, John R; Liu, Lianqi; Natarajan, Loki; He, Feng; Cornejo, Monique; Lawton, Susan; Parker, Barbara A; Sadler, Georgia R; Ancoli-Israel, Sonia

2010-01-01

Purpose Estimates of insomnia in breast cancer patients are high, with reports of poor sleep lasting years after completion of cancer treatment. This randomized controlled crossover pilot study looked at the effects of individual cognitive behavioral therapy for insomnia (IND-CBT-I) on sleep in breast cancer survivors. Patients and methods Twenty-one participants were randomly assigned to either a treatment group (six weekly IND-CBT-I sessions followed by six weeks of follow up) or a delayed treatment control group (no treatment for six weeks followed by six weekly IND-CBT-I sessions). Of these, 14 participants completed the pilot study (six in the treatment group and eight in the delayed treatment control group). Results Self-rated insomnia was significantly improved in the treatment group compared to the waiting period in the delayed treatment control group. The pooled pre-post-IND-CBT-I analyses revealed improvements in self-rated insomnia, sleep quality, and objective measures of sleep. Conclusions These preliminary results suggest that IND-CBT-I is appropriate for improving sleep in breast cancer survivors. Individual therapy in a clinic or private practice may be a more practical option for this population as it is more easily accessed and readily available in an outpatient setting. PMID:23616695

A pilot investigation in constructing crisis communications: what leads to best practice?

Science.gov (United States)

Firestone, Rachel M; Everly, George S

2013-01-01

Crisis communications can play an important role in mitigating, or exacerbating, the psychological and behavioral reactions to critical incidents and disasters. Effective crisis communications can serve to mitigate anxiogenesis and direct rapid and focused rescue, recovery, and rehabilitative operations. Ambiguous and/or deceptive communications can serve to worsen mental health reactions and delay operational response and recovery (Everly, Strouse, & Everly, 2010). It seems, therefore, that inquiry into the content of acute crisis communications would be warranted Said more simply, given limited time, cryptic messaging in social media, and the "sound bite" mentality that seems to govern news dissemination, it is important to identify the most important content to convey in the wake of critical incidents and disasters. This paper reports on a pilot investigation into "best practices" for the construction of acute crisis communications.

10-MWe pilot-plant-receiver panel test requirements document solar thermal test facility

Energy Technology Data Exchange (ETDEWEB)

1978-08-25

Testing plans for a full-scale test receiver panel and supporting hardware which essentially duplicate both physically and functionally, the design planned for the Barstow Solar Pilot Plant are presented. Testing is to include operation during normal start and shutdown, intermittent cloud conditions, and emergencies to determine the panel's transient and steady state operating characteristics and performance under conditions equal to or exceeding those expected in the pilot plant. The effects of variations of input and output conditions on receiver operation are also to be investigated. Test hardware are described, including the pilot plant receiver, the test receiver assembly, receiver panel, flow control, electrical control and instrumentation, and structural assembly. Requirements for the Solar Thermal Test Facility for the tests are given. The safety of the system is briefly discussed, and procedures are described for assembly, installation, checkout, normal and abnormal operations, maintenance, removal and disposition. Also briefly discussed are quality assurance, contract responsibilities, and test documentation. (LEW)

Online CBT life skills programme for low mood and anxiety: study protocol for a pilot randomized controlled trial.

Science.gov (United States)

Williams, Christopher; McClay, Carrie-Anne; Martinez, Rebeca; Morrison, Jill; Haig, Caroline; Jones, Ray; Farrand, Paul

2016-04-27

Low mood is a common mental health problem with significant health consequences. Studies have shown that cognitive behavioural therapy (CBT) is an effective treatment for low mood and anxiety when delivered one-to-one by an expert practitioner. However, access to this talking therapy is often limited and waiting lists can be long, although a range of low-intensity interventions that can increase access to services are available. These include guided self-help materials delivered via books, classes and online packages. This project aims to pilot a randomized controlled trial of an online CBT-based life skills course with community-based individuals experiencing low mood and anxiety. Individuals with elevated symptoms of depression will be recruited directly from the community via online and newspaper advertisements. Participants will be remotely randomized to receive either immediate access or delayed access to the Living Life to the Full guided online CBT-based life skills package, with telephone or email support provided whilst they use the online intervention. The primary end point will be at 3 months post-randomization, at which point the delayed-access group will be offered the intervention. Levels of depression, anxiety, social functioning and satisfaction will be assessed. This pilot study will test the trial design, and ability to recruit and deliver the intervention. Drop-out rates will be assessed and the completion and acceptability of the package will be investigated. The study will also inform a sample size power calculation for a subsequent substantive randomized controlled trial. ISRCTN ISRCTN12890709.

Pilot Weather Reports

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Aviation weather reports relayed from pilots to FAA air traffic controllers or National Weather Service personnel. Elements include sky cover, turbulence, wind...

Evaluation of homoeopathic treatment in polycystic ovary syndrome: A single-blind, randomised, placebo-controlled pilot study

Directory of Open Access Journals (Sweden)

Chetna Deep Lamba

2018-01-01

Full Text Available Background and Objectives: This study was conducted with the primary objective of evaluating efficacy of Homoeopathy in establishing the menstrual regularity with improvement in either ultrasonological findings or hirsutism/acne. The quality of life was also assessed using polycystic ovary syndrome questionnaire (PCOSQ. Materials and Methods: A single-blind, randomised, placebo-controlled pilot study was conducted from February 2014 to May 2015 at two research centres. The cases fulfilling the eligibility criteria were enrolled (n = 60 and randomised to either the homoeopathic intervention (HI (n = 30 or identical placebo (P (n = 30 with uniform lifestyle modification (LSM for 6 months. Results: The menstrual regularity with improvement in other signs/symptoms was observed in 60% of the cases (n = 18 in HI + LSM group and none (n = 0 in control group (P = 0.001. Statistically significant difference (P = 0.016 was observed in reduction of intermenstrual duration (from 76.1 ± 37.7 to 46.6 ± 38.7 days in HI + LSM in comparison to placebo + LSM group (from 93.0 ± 65.2 to 93.9 ± 96.2 days. In PCOSQ, also, significant improvement was observed in HI group in domains of weight, fertility, emotions and menstrual problems (P < 0.05 with no difference in body hair (P = 0.708. No change was observed in respect of improvement in the ultrasound findings. Pulsatilla was the most frequently indicated medicine (n = 12, 40%. Conclusion: HI along with LSM has shown promising outcome; further comparative study with standard conventional treatment on adequate sample size is desirable.

Sealable joint steel sheet piling for groundwater control and remediation: Case histories

International Nuclear Information System (INIS)

Smyth, D.; Jowett, R.; Gamble, M.

1997-01-01

The Waterloo Barrier trademark steel sheet piling (patents pending) incorporates a cavity at each interlocking joint that is flushed clean and injected with sealant after the piles have been driven into the ground to form a vertical cutoff wall. The installation and sealing procedures allow for a high degree of quality assurance and control. Bulk wall hydraulic conductivities of 10 -8 to 10 -10 cm/sec have been demonstrated at field installations. Recent case histories are presented in which Waterloo Barrier trademark cutoff walls are used to prevent off-site migration of contaminated groundwater or soil gases to adjacent property and waterways. Full enclosures to isolate DNAPL source zones or portions of contaminated aquifers for pilot-scale remediation testing will also be described. Monitoring data will be used to demonstrate the effectiveness of the Waterloo Barrier trademark in these applications

Hockey Fans in Training: A Pilot Pragmatic Randomized Controlled Trial.

Science.gov (United States)

Petrella, Robert J; Gill, Dawn P; Zou, Guangyong; DE Cruz, Ashleigh; Riggin, Brendan; Bartol, Cassandra; Danylchuk, Karen; Hunt, Kate; Wyke, Sally; Gray, Cindy M; Bunn, Christopher; Zwarenstein, Merrick

2017-12-01

Hockey Fans in Training (Hockey FIT) is a gender-sensitized weight loss and healthy lifestyle program. We investigated 1) feasibility of recruiting and retaining overweight and obese men into a pilot pragmatic randomized controlled trial and 2) potential for Hockey FIT to lead to weight loss and improvements in other outcomes at 12 wk and 12 months. Male fans of two ice hockey teams (35-65 yr; body mass index ≥28 kg·m) located in Ontario (Canada) were randomized to intervention (Hockey FIT) or comparator (wait-list control). Hockey FIT includes a 12-wk active phase (weekly, coach-led group meetings including provision of dietary information, practice of behavior change techniques, and safe exercise sessions plus incremental pedometer walking) and a 40-wk minimally supported phase (smartphone app for sustaining physical activity, private online social network, standardized e-mails, booster session/reunion). Measurement at baseline and 12 wk (both groups) and 12 months (intervention group only) included clinical outcomes (e.g., weight) and self-reported physical activity, diet, and self-rated health. Eighty men were recruited in 4 wk; trial retention was >80% at 12 wk and >75% at 12 months. At 12 wk, the intervention group lost 3.6 kg (95% confidence interval, -5.26 to -1.90 kg) more than the comparator group (P < 0.001) and maintained this weight loss to 12 months. The intervention group also demonstrated greater improvements in other clinical measures, physical activity, diet, and self-rated health at 12 wk; most sustained to 12 months. Results suggest feasible recruitment/retention of overweight and obese men in the Hockey FIT program. Results provide evidence for the potential effectiveness of Hockey FIT for weight loss and improved health in at-risk men and, thus, evidence to proceed with a definitive trial.

Applications of pilot scanning behavior to integrated display research

Science.gov (United States)

Waller, M. C.

1977-01-01

The oculometer is an electrooptical device designed to measure pilot scanning behavior during instrument approaches and landing operations. An overview of some results from a simulation study is presented to illustrate how information from the oculometer installed in a visual motion simulator, combined with measures of performance and control input data, can provide insight into the behavior and tactics of individual pilots during instrument approaches. Differences in measured behavior of the pilot subjects are pointed out; these differences become apparent in the way the pilots distribute their visual attention, in the amount of control activity, and in selected performance measures. Some of these measured differences have diagnostic implications, suggesting the use of the oculometer along with performance measures as a pilot training tool.

Synthetic Vision Systems in GA Cockpit-Evaluation of Basic Maneuvers Performed by Low Time GA Pilots During Transition from VMC to IMC

Science.gov (United States)

Takallu, M. A.; Wong, D. T.; Uenking, M. D.

2002-01-01

An experimental investigation was conducted to study the effectiveness of modern flight displays in general aviation cockpits for mitigating Low Visibility Loss of Control and the Controlled Flight Into Terrain accidents. A total of 18 General Aviation (GA) pilots with private pilot, single engine land rating, with no additional instrument training beyond private pilot license requirements, were recruited to evaluate three different display concepts in a fixed-based flight simulator at the NASA Langley Research Center's General Aviation Work Station. Evaluation pilots were asked to continue flight from Visual Meteorological Conditions (VMC) into Instrument Meteorological Conditions (IMC) while performing a series of 4 basic precision maneuvers. During the experiment, relevant pilot/vehicle performance variables, pilot control inputs and physiological data were recorded. Human factors questionnaires and interviews were administered after each scenario. Qualitative and quantitative data have been analyzed and the results are presented here. Pilot performance deviations from the established target values (errors) were computed and compared with the FAA Practical Test Standards. Results of the quantitative data indicate that evaluation pilots committed substantially fewer errors when using the Synthetic Vision Systems (SVS) displays than when they were using conventional instruments. Results of the qualitative data indicate that evaluation pilots perceived themselves to have a much higher level of situation awareness while using the SVS display concept.

Investigation of Pertussis Cases in a Texas County, 2008-2012.

Science.gov (United States)

Staudt, Amanda; Mangla, Anil T; Alamgir, Hasanat

2015-07-01

Within the past 25 years, there has been a dramatic increase in the incidence of pertussis cases in the United States. As such, this investigation reports on the high-risk groups and describes risk factors of pertussis cases in a large Texas county. This study was a cross-sectional analysis of data collected by health department employees using the Texas Department of State Health Service's Pertussis Case Track Record, which is the standard investigation form for collecting vital information on pertussis cases. We extracted and analyzed county-level data for a 5-year period (2008-2012). The study population at risk included all current residents in this county, and cases included all who were clinically diagnosed as having confirmed or probable pertussis cases that were reported to the health department according to the Centers for Disease Control and Prevention case definition. The vaccination status of a case was defined as fully vaccinated, partially vaccinated, or not vaccinated. A total of 198 probable and confirmed pertussis cases were included in this analysis. Most of the cases were infants younger than 1 year old (n = 107). The largest category of cases was not vaccinated and of the rest, 32.8% were partially vaccinated, 17.2% had unknown vaccination status, and 13.1% were fully vaccinated. Only 48 (24.2%) sources of exposure were identified and they included fathers (14.6%), sisters (14.6%), brothers (14.6%), other children (14.6%), and mothers (12.5%). Many sources of exposure (n = 26, 54.1%) were unaware of their vaccination history. Hispanics accounted for 84.5% of cases in the younger than 1 year old group and 88.9% of cases were in the 1 to 2 years old group. With respect to race/ethnicity and vaccination status of the cases, 39.46% of Hispanics, 32% of whites, and 50% of blacks were reported to be unvaccinated. Increasing pertussis vaccination coverage among children, as well as providing booster shots to adults with special attention on the

External data required timely response by the Trial Steering-Data Monitoring Committee for the NALoxone InVEstigation (N-ALIVE pilot trial

Directory of Open Access Journals (Sweden)

Sheila M. Bird

2017-03-01

Full Text Available The prison-based N-ALIVE pilot trial had undertaken to notify the Research Ethics Committee and participants if we had reason to believe that the N-ALIVE pilot trial would not proceed to the main trial. In this paper, we describe how external data for the third year of before/after evaluation from Scotland's National Naloxone Programme, a related public health policy, were anticipated by eliciting prior opinion about the Scottish results in the month prior to their release as official statistics. We summarise how deliberations by the N-ALIVE Trial Steering-Data Monitoring Committee (TS-DMC on N-ALIVE's own interim data, together with those on naloxone-on-release (NOR from Scotland, led to the decision to cease randomization in the N-ALIVE pilot trial and recommend to local Principal Investigators that NOR be offered to already-randomized prisoners who had not yet been released.

Application of digital human modeling and simulation for vision analysis of pilots in a jet aircraft: a case study.

Science.gov (United States)

Karmakar, Sougata; Pal, Madhu Sudan; Majumdar, Deepti; Majumdar, Dhurjati

2012-01-01

Ergonomic evaluation of visual demands becomes crucial for the operators/users when rapid decision making is needed under extreme time constraint like navigation task of jet aircraft. Research reported here comprises ergonomic evaluation of pilot's vision in a jet aircraft in virtual environment to demonstrate how vision analysis tools of digital human modeling software can be used effectively for such study. Three (03) dynamic digital pilot models, representative of smallest, average and largest Indian pilot population were generated from anthropometric database and interfaced with digital prototype of the cockpit in Jack software for analysis of vision within and outside the cockpit. Vision analysis tools like view cones, eye view windows, blind spot area, obscuration zone, reflection zone etc. were employed during evaluation of visual fields. Vision analysis tool was also used for studying kinematic changes of pilot's body joints during simulated gazing activity. From present study, it can be concluded that vision analysis tool of digital human modeling software was found very effective in evaluation of position and alignment of different displays and controls in the workstation based upon their priorities within the visual fields and anthropometry of the targeted users, long before the development of its physical prototype.

Recruitment to online therapies for depression: pilot cluster randomized controlled trial.

Science.gov (United States)

Jones, Ray B; Goldsmith, Lesley; Hewson, Paul; Williams, Christopher J

2013-03-05

Raising awareness of online cognitive behavioral therapy (CBT) could benefit many people with depression, but we do not know how purchasing online advertising compares to placing free links from relevant local websites in increasing uptake. To pilot a cluster randomized controlled trial (RCT) comparing purchase of Google AdWords with placing free website links in raising awareness of online CBT resources for depression in order to better understand research design issues. We compared two online interventions with a control without intervention. The pilot RCT had 4 arms, each with 4 British postcode areas: (A) geographically targeted AdWords, (B) adverts placed on local websites by contacting website owners and requesting links be added, (C) both interventions, (D) control. Participants were directed to our research project website linking to two freely available online CBT resource sites (Moodgym and Living Life To The Full (LLTTF)) and two other depression support sites. We used data from (1) AdWords, (2) Google Analytics for our project website and for LLTTF, and (3) research project website. We compared two outcomes: (1) numbers with depression accessing the research project website, and then chose an onward link to one of the two CBT websites, and (2) numbers registering with LLTTF. We documented costs, and explored intervention and assessment methods to make general recommendations to inform researchers aiming to use similar methodologies in future studies. Trying to place local website links appeared much less cost effective than AdWords and although may prove useful for service delivery, was not worth pursuing in the context of the current study design. Our AdWords intervention was effective in recruiting people to the project website but our location targeting "leaked" and was not as geographically specific as claimed. The impact on online CBT was also diluted by offering participants other choices of destinations. Measuring the impact on LLTTF use was

Pilot-Scale Demonstration of ALTA for NOx Control in Pulverized Coal-Fired Boilers

Energy Technology Data Exchange (ETDEWEB)

Andrew Fry; Devin Davis; Marc Cremer; Bradley Adams

2008-04-30

This report describes computational fluid dynamics (CFD) modeling and pilot-scale testing conducted to demonstrate the ability of the Advanced Layered Technology Approach (ALTA) to reduce NO{sub x} emissions in a pulverized coal (PC) boiler. Testing specifically focused on characterizing NO{sub x} behavior with deep burner staging combined with Rich Reagent Injection (RRI). Tests were performed in a 4 MBtu/hr pilot-scale furnace at the University of Utah. Reaction Engineering International (REI) led the project team which included the University of Utah and Combustion Components Associates (CCA). Deep burner staging and RRI, combined with selective non-catalytic reduction (SNCR), make up the Advanced Layered Technology Approach (ALTA) for NO{sub x} reduction. The application of ALTA in a PC environment requires homogenization and rapid reaction of post-burner combustion gases and has not been successfully demonstrated in the past. Operation of the existing low-NO{sub x} burner and design and operation of an application specific ALTA burner was guided by CFD modeling conducted by REI. Parametric pilot-scale testing proved the chemistry of RRI in a PC environment with a NOx reduction of 79% at long residence times and high baseline NOx rate. At representative particle residence times, typical operation of the dual-register low-NO{sub x} burner provided an environment that was unsuitable for NO{sub x} reduction by RRI, showing no NOx reduction. With RRI, the ALTA burner was able to produce NO{sub x} emissions 20% lower than the low-NO{sub x} burner, 76 ppmv vs. 94 ppmv, at a burner stoichiometric ratio (BSR) of 0.7 and a normalized stoichiometric ratio (NSR) of 2.0. CFD modeling was used to investigate the application of RRI for NO{sub x} control on a 180 MW{sub e} wall-fired, PC boiler. A NO{sub x} reduction of 37% from baseline (normal operation) was predicted using ALTA burners with RRI to produce a NO{sub x} emission rate of 0.185 lb/MBtu at the horizontal nose of

Investigations into the operating behavior of separation nozzle cascades for uranium-235 enrichment in a 10-stage pilot plant

International Nuclear Information System (INIS)

Bley, P.; Hein, H.; Linder, G.

1984-03-01

The separation nozzle method developed by the Karlsruhe Nuclear Research Center is based on the centrifugal force in a curved jet consisting of uranium hexafluoride and a light auxiliary gas. To determine in experiments the operating and controlling behavior of separation nozzle cascades a 10-stage pilot plant was erected some year ago. This plant was transferred to the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN) in Belo Horizonte as a donation made within the framework of the German-Brazilian Agreement on scientific cooperation in the field of uranium enrichment. The plant previously equipped with single deflection systems was modified to operate with the double deflection system envisaged for commercial plants. A controlling concept meanwhile developed and improved for separation nozzle cascades equipped with single and double deflection systems was verified experimentally and optimized at the pilot plant of the CDTN. A comparison of the experimental operating behavior with the operating behavior calculated by simulation programs has confirmed the faithfulness of simulation of the computer codes developed to apply to cascades with double deflection systems as well. (orig.) [de

Malaria prevention knowledge, attitudes, and practices (KAP) among international flying pilots and flight attendants of a US commercial airline.

Science.gov (United States)

Selent, Monica; de Rochars, Valery M Beau; Stanek, Danielle; Bensyl, Diana; Martin, Barbara; Cohen, Nicole J; Kozarsky, Phyllis; Blackmore, Carina; Bell, Teal R; Marano, Nina; Arguin, Paul M

2012-12-01

In 2010, malaria caused approximately 216 million infections in people and 655,000 deaths. In the United States, imported malaria cases occur every year, primarily in returning travelers and immigrants from endemic countries. In 2010, five Plasmodium falciparum malaria cases occurred among crew members of one US commercial airline company (Airline A). This investigation aimed to assess the malaria prevention knowledge, attitudes, and practices (KAP) of Airline A crew members to provide information for potential interventions. The web link to a self-administered on-line survey was distributed by internal company communications to Airline A pilots and flight attendants (FA) eligible for international travel. The survey collected demographic information as well as occupation, work history, and malaria prevention education. Of approximately 7,000 nonrandomly selected crew members, 220 FA and 217 pilots completed the survey (6%). Respondents correctly identified antimalarial medication (91% FA, 95% pilots) and insect repellents (96% FA, 96% pilots) as effective preventive measures. While in malaria-intense destinations, few FA and less than half of pilots always took antimalarial medication (4% FA, 40% pilots) yet many often spent greater than 30 minutes outdoors after sundown (71% FA, 66% pilots). Less than half in both groups always used insect repellents (46% FA, 47% pilots). Many respondents were unaware of how to get antimalarial medications (52% FA, 30% pilots) and were concerned about their side effects (61% FA, 31% pilots). Overall, FA and pilots demonstrated good knowledge of malaria prevention, but many performed risky activities while practicing only some recommended malaria preventive measures. Malaria prevention education should focus on advance notification if traveling to a malaria-endemic area, how to easily obtain antimalarial medications, and the importance of practicing all recommended preventive measures. © 2012 International Society of Travel

Can iridology detect susceptibility to cancer? A prospective case-controlled study.

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Münstedt, Karsten; El-Safadi, Samer; Brück, Friedel; Zygmunt, Marek; Hackethal, Andreas; Tinneberg, Hans-Rudolf

2005-06-01

This prospective case-control study aimed to investigate the value of iridology as a diagnostic tool in detecting some common cancers. One hundred ten (110) subjects were enrolled in the study: 68 subjects had histologically proven cancers of the breast, ovary, uterus, prostate, or colorectum, and 42 were control subjects. All subjects were examined by an experienced practitioner of iridology, who was unaware of their gender or medical details. He was allowed to suggest up to five diagnoses for each subject and his results were then compared with each subject's medical diagnosis to determine the accuracy of iridology in detecting malignancy. Iridology identified the correct diagnosis in only 3 cases (sensitivity, 0.04). Iridology was of no value in diagnosing the cancers investigated in this study.

A pilot scale demonstration of the DWPF process control and product verification strategy

International Nuclear Information System (INIS)

Hutson, N.D.; Jantzen, C.M.; Beam, D.C.

1992-01-01

The Defense Waste Processing Facility (DWPF) has been designed and constructed to immobilize Savannah River Site high level liquid waste within a durable borosilicate glass matrix for permanent storage. The DWPF will be operated to produce a glass product which must meet a number of product property constraints which are dependent upon the final product composition. During actual operations, the DWPF will control the properties of the glass product by the controlled blending of the waste streams with a glass-forming frit to produce the final melter feed slurry. The DWPF will verify control of the glass product through analysis of vitrified samples of slurry material. In order to demonstrate the DWPF process control and product verification strategy, a pilot-scale vitrification research facility was operated in three discrete batches using simulated DWPF waste streams. All of the DWPF process control methodologies were followed and the glass produce from each experiment was leached according to the Product Consistency Test. Results of the campaign are summarized

β-trace protein as a diagnostic marker for perilymphatic fluid fistula: a prospective controlled pilot study to test a sample collection technique.

Science.gov (United States)

Bachmann-Harildstad, Gregor; Stenklev, Niels Christian; Myrvoll, Elin; Jablonski, Greg; Klingenberg, Olav

2011-01-01

The diagnosis of perilymphatic fluid (PLF) fistula is still challenging. Perilymphatic fluid fistula is one possible complication after stapedotomy or cochlear implant surgery. We have performed a prospective diagnostic pilot study to further investigate β-trace protein (β-TP) as a marker for PLF fistula. In this pilot study, we tested the sensitivity of the β-TP marker using a simple method for sample collection from the tympanic cavity. Prospective controlled diagnostic study. Two-center tertiary referral hospitals. A total of 35 adult patients undergoing ear surgery were included. Subjects were divided into 2 groups: 1) 19 patients undergoing stapedotomy were investigated for PLF fistula in samples obtained from the tympanic cavity and 2) 16 patients undergoing myringoplasty were investigated for PLF fistula in samples from the tympanic cavity. This group served as the control. Mean age +/- SD at surgery was 49.9 +/- 8.0 years in the study group and 39.69 +/- 15.47 years in the control group. β-Trace protein (prostaglandin D synthase) in tympanic cavity samples and serum samples was analyzed. The samples were collected by gradually filling the tympanic cavity with 100 to 200 μl sodium chloride and by immediately collecting a volume of 60 to 100 μl in a mucus specimen set container. The concentration of β-TP was quantified using laser nephelometry. The median β-TP in the study group was 0.8 mg/L (range, 0.05-4.5 mg/L). In the control group, the median β-TP value was 0.16 mg/L (range, 0.01-0.36 mg/L). Thirty-five percent of the values in the study group were below the highest value in the negative control group. The β-TP values of the tympanic cavity samples were significantly higher in the study group than in controls (p = 0.0001). The serum values were 0.55 +/- 0.18 and 0.53 +/- 0.11 mg/L, respectively. It may be feasible to test for PLF fistula using β-TP in samples from the tympanic cavity. Our results, however, suggest a relative low diagnostic

Investigation of display issues relevant to the presentation of aircraft fault information

Science.gov (United States)

Allen, Donald M.

1989-01-01

This research, performed as a part of NASA Langley's Faultfinder project, investigated display implementation issues related to the introduction of real time fault diagnostic systems into next generation commercial aircraft. Three major issues were investigated: visual display styles for presenting fault related information to the crew, the form the output from the expert system should take, and methods for filtering fault related information for presentation to the crew. Twenty-four flight familiar male volunteers participated as subjects. Five subjects were NASA test pilots, six were Commercial Airline Pilots, seven were Air Force Lear Jet pilots, and six were NASA personnel familiar with flight (non-pilots). Subjects were presented with aircraft subsystem information on a CRT screen. They were required to identify the subsystems presented in a display and to remember the state (normal or abnormal) of subsystem parameter information contained in the display. The results of the study indicated that in the simpler experimental test cases (i.e., those involving single subsystem failures and composite hypothesis displays) subjects' performance did not differ across the different display formats. However, for the more complex cases (i.e., those involving multiple subsystem faults and multiple hypotheses displays), subjects' performance was superior in the text- and picture-based display formats compared to the symbol-based format. In addition, the findings suggest that a layered approached to information display is appropriate.

Carotid duplex ultrasound and transcranial Doppler findings in commercial divers and pilots.

Science.gov (United States)

Dormanesh, Banafshe; Vosoughi, Kia; Akhoundi, Fahimeh H; Mehrpour, Masoud; Fereshtehnejad, Seyed-Mohammad; Esmaeili, Setareh; Sabet, Azin Shafiee

2016-12-01

The risky working environments of divers and pilots, and the possible role of extreme ambient pressure in carotid stenosis, make ischemic stroke an important occupational concern among these professionals. In this study, we aimed to evaluate the association of being exposed to hyperbaric or hypobaric conditions with carotid artery stenosis by comparing common carotid intima-media thickness (CCIMT) and blood flow velocities of cerebral arteries in divers and pilots using carotid duplex ultrasound (CDUS) and transcranial Doppler (TCD). CDUS and transtemporal TCD were performed in 29 divers, 36 pilots and 30 control participants. Medical history, blood pressure, lipid profile and blood sugar were recorded to control the previously well-known risk factors of atherosclerosis. Findings of the CDUS and TCD [including: CCIMT and blood flow velocities of internal carotid artery (ICA), common carotid artery (CCA), and middle cerebral artery (MCA)] of divers and pilots were compared with those of the control group using regression analysis models. Both right and left side CCIMT were significantly higher in divers (P < 0.05) and pilots (P < 0.05) in comparison with the control group. Carotid index [peak systolic velocity (PSV) of ICA/PSV of CCA) of divers and pilots were also higher than the control group. TCD findings were not significantly different between divers, pilots, and the control group. Increased CCIMT and carotid index in diver and pilot groups appear to be suggestive of accelerated atherosclerosis of carotid artery in these occupational groups.

Cognitive Workload and Psychophysiological Parameters During Multitask Activity in Helicopter Pilots.

Science.gov (United States)

Gaetan, Sophie; Dousset, Erick; Marqueste, Tanguy; Bringoux, Lionel; Bourdin, Christophe; Vercher, Jean-Louis; Besson, Patricia

2015-12-01

Helicopter pilots are involved in a complex multitask activity, implying overuse of cognitive resources, which may result in piloting task impairment or in decision-making failure. Studies usually investigate this phenomenon in well-controlled, poorly ecological situations by focusing on the correlation between physiological values and either cognitive workload or emotional state. This study aimed at jointly exploring workload induced by a realistic simulated helicopter flight mission and emotional state, as well as physiological markers. The experiment took place in the helicopter full flight dynamic simulator. Six participants had to fly on two missions. Workload level, skin conductance, RMS-EMG, and emotional state were assessed. Joint analysis of psychological and physiological parameters associated with workload estimation revealed particular dynamics in each of three profiles. 1) Expert pilots showed a slight increase of measured physiological parameters associated with the increase in difficulty level. Workload estimates never reached the highest level and the emotional state for this profile only referred to positive emotions with low emotional intensity. 2) Non-Expert pilots showed increasing physiological values as the perceived workload increased. However, their emotional state referred to either positive or negative emotions, with a greater variability in emotional intensity. 3) Intermediate pilots were similar to Expert pilots regarding emotional states and similar to Non-Expert pilots regarding physiological patterns. Overall, high interindividual variability of these results highlight the complex link between physiological and psychological parameters with workload, and question whether physiology alone could predict a pilot's inability to make the right decision at the right time.

Should Controls With Respiratory Symptoms Be Excluded From Case-Control Studies of Pneumonia Etiology? Reflections From the PERCH Study.

Science.gov (United States)

Higdon, Melissa M; Hammitt, Laura L; Deloria Knoll, Maria; Baggett, Henry C; Brooks, W Abdullah; Howie, Stephen R C; Kotloff, Karen L; Levine, Orin S; Madhi, Shabir A; Murdoch, David R; Scott, J Anthony G; Thea, Donald M; Driscoll, Amanda J; Karron, Ruth A; Park, Daniel E; Prosperi, Christine; Zeger, Scott L; O'Brien, Katherine L; Feikin, Daniel R

2017-06-15

Many pneumonia etiology case-control studies exclude controls with respiratory illness from enrollment or analyses. Herein we argue that selecting controls regardless of respiratory symptoms provides the least biased estimates of pneumonia etiology. We review 3 reasons investigators may choose to exclude controls with respiratory symptoms in light of epidemiologic principles of control selection and present data from the Pneumonia Etiology Research for Child Health (PERCH) study where relevant to assess their validity. We conclude that exclusion of controls with respiratory symptoms will result in biased estimates of etiology. Randomly selected community controls, with or without respiratory symptoms, as long as they do not meet the criteria for case-defining pneumonia, are most representative of the general population from which cases arose and the least subject to selection bias. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

Efficiency of "Prescribe Vida Saludable", a health promotion innovation. Pilot phase.

Science.gov (United States)

Sanz-Guinea, Aitor; Espinosa, Maite; Grandes, Gonzalo; Sáncheza, Álvaro; Martínez, Catalina; Pombo, Haizea; Bully, Paola; Cortada, Josep

"Prescribe Vida Saludable" (PVS) is an organisational innovation designed to optimise the promotion of multiple healthy habits in primary healthcare. It aims to estimate the cost effectiveness and cost-utility of prescribing physical activity in the pilot phase of the PVS programme, compared to the routine clinical practice of promoting physical activity in primary healthcare. An economic evaluation of the quasi-experimental pilot phase of PVS was carried out. In the four control centres, a systematic sample was selected of 194 patients who visited the centre in a single year and who did not comply with physical activity recommendations. In the four intervention centres, 122 patients who received their first physical activity prescription were consecutively enrolled. The costs were evaluated from the perspective of the PVS programme using bottom-up methodology. The effectiveness (proportion of patients who changed their physical activity) as well as the utility were evaluated at baseline and after 3 months. The incremental cost-utility ratio (ICUR) and the incremental cost-effectiveness ratio (ICER) were calculated and a sensitivity analysis was performed with bootstrapping and 1,000 replications. Information was obtained from 35% of control cases and 62% of intervention cases. The ICUR was €1,234.66/Quality Adjusted Life Years (QALY) and the ICER was €4.12. In 98.3% of the simulations, the ICUR was below the €30,000/QALY threshold. The prescription of physical activity was demonstrably within acceptable cost-utility limits in the pilot PVS phase, even from a conservative perspective. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

Accounting for control mislabeling in case-control biomarker studies.

Science.gov (United States)

Rantalainen, Mattias; Holmes, Chris C

2011-12-02

In biomarker discovery studies, uncertainty associated with case and control labels is often overlooked. By omitting to take into account label uncertainty, model parameters and the predictive risk can become biased, sometimes severely. The most common situation is when the control set contains an unknown number of undiagnosed, or future, cases. This has a marked impact in situations where the model needs to be well-calibrated, e.g., when the prediction performance of a biomarker panel is evaluated. Failing to account for class label uncertainty may lead to underestimation of classification performance and bias in parameter estimates. This can further impact on meta-analysis for combining evidence from multiple studies. Using a simulation study, we outline how conventional statistical models can be modified to address class label uncertainty leading to well-calibrated prediction performance estimates and reduced bias in meta-analysis. We focus on the problem of mislabeled control subjects in case-control studies, i.e., when some of the control subjects are undiagnosed cases, although the procedures we report are generic. The uncertainty in control status is a particular situation common in biomarker discovery studies in the context of genomic and molecular epidemiology, where control subjects are commonly sampled from the general population with an established expected disease incidence rate.

Development and evaluation of an intervention aiming to reduce fatigue in airline pilots: design of a randomised controlled trial.

Science.gov (United States)

van Drongelen, Alwin; van der Beek, Allard J; Hlobil, Hynek; Smid, Tjabe; Boot, Cécile R L

2013-08-26

A considerable percentage of flight crew reports to be fatigued regularly. This is partly caused by irregular and long working hours and the crossing of time zones. It has been shown that persistent fatigue can lead to health problems, impaired performance during work, and a decreased work-private life balance. It is hypothesized that an intervention consisting of tailored advice regarding exposure to daylight, optimising sleep, physical activity, and nutrition will lead to a reduction of fatigue in airline pilots compared to a control group, which receives a minimal intervention with standard available information. The study population will consist of pilots of a large airline company. All pilots who posses a smartphone or tablet, and who are not on sick leave for more than four weeks at the moment of recruitment, will be eligible for participation.In a two-armed randomised controlled trial, participants will be allocated to an intervention group that will receive the tailored advice to optimise exposure to daylight, sleep, physical activity and nutrition, and a control group that will receive standard available information. The intervention will be applied using a smartphone application and a website, and will be tailored on flight- and participant-specific characteristics. The primary outcome of the study is perceived fatigue. Secondary outcomes are need for recovery, duration and quality of sleep, dietary and physical activity behaviours, work-private life balance, general health, and sickness absence. A process evaluation will be conducted as well. Outcomes will be measured at baseline and at three and six months after baseline. This paper describes the development of an intervention for airline pilots, consisting of tailored advice (on exposure to daylight and sleep-, physical activity, and nutrition) applied into a smartphone application. Further, the paper describes the design of the randomised controlled trial evaluating the effect of the intervention on

A placebo-controlled investigation of synaesthesia-like experiences under LSD.

Science.gov (United States)

Terhune, Devin B; Luke, David P; Kaelen, Mendel; Bolstridge, Mark; Feilding, Amanda; Nutt, David; Carhart-Harris, Robin; Ward, Jamie

2016-07-29

The induction of synaesthesia in non-synaesthetes has the potential to illuminate the mechanisms that contribute to the development of this condition and the shaping of its phenomenology. Previous research suggests that lysergic acid diethylamide (LSD) reliably induces synaesthesia-like experiences in non-synaesthetes. However, these studies suffer from a number of methodological limitations including lack of a placebo control and the absence of rigorous measures used to test established criteria for genuine synaesthesia. Here we report a pilot study that aimed to circumvent these limitations. We conducted a within-groups placebo-controlled investigation of the impact of LSD on colour experiences in response to standardized graphemes and sounds and the consistency and specificity of grapheme- and sound-colour associations. Participants reported more spontaneous synaesthesia-like experiences under LSD, relative to placebo, but did not differ across conditions in colour experiences in response to inducers, consistency of stimulus-colour associations, or in inducer specificity. Further analyses suggest that individual differences in a number of these effects were associated with the propensity to experience states of absorption in one's daily life. Although preliminary, the present study suggests that LSD-induced synaesthesia-like experiences do not exhibit consistency or inducer-specificity and thus do not meet two widely established criteria for genuine synaesthesia. Copyright © 2016 Elsevier Ltd. All rights reserved.

Future-oriented computerized information system for power plant process control in a pilot project at Philippsburg nuclear power plant

International Nuclear Information System (INIS)

Woehrle, G.; Kraft, M.

1988-01-01

The motivation for the pilot project at Philippsburg nuclear power plant resulted from the Three Mile Island accident in 1979. The primary task embraces an efficient computer-aided reduction of information when a fault occurs based on a process engineering analysis of the information accrued. Accompanying this are a consolidation and evaluation of the information available in the control room. In this pilot project the new tasks of status monitoring, information reduction and operationalcontrol have been realized for the first time using a computer-aided process information system. In addition to the existing control computer, an information computer with approximately 1200 analogue and about 10000 binary signals has been installed. The installation of the system was completed in 1984 and in the meantime initial operational experience has become available. (orig.) [de

Sleep education improves the sleep duration of adolescents: a randomized controlled pilot study.

Science.gov (United States)

Kira, Geoff; Maddison, Ralph; Hull, Michelle; Blunden, Sarah; Olds, Timothy

2014-07-15

To determine the feasibility and pilot a sleep education program in New Zealand high school students. A parallel, two-arm randomized controlled pilot trial was conducted. High school students (13 to 16 years) were randomly allocated to either a classroom-based sleep education program intervention (n = 15) or to a usual curriculum control group (n = 14). The sleep education program involved four 50-minute classroom-based education sessions with interactive groups. Students completed a 7-day sleep diary, a sleep questionnaire (including sleep hygiene, knowledge and problems) at baseline, post-intervention (4 weeks) and 10 weeks follow-up. An overall treatment effect was observed for weekend sleep duration (F 1,24 = 5.21, p = 0.03). Participants in the intervention group slept longer during weekend nights at 5 weeks (1:37 h:min, p = 0.01) and 10 weeks: (1:32 h:min, p = 0.03) compared to those in the control group. No differences were found between groups for sleep duration on weekday nights. No significant differences were observed between groups for any of the secondary outcomes (sleep hygiene, sleep problems, or sleep knowledge). A sleep education program appears to increase weekend sleep duration in the short term. Although this program was feasible, most schools are under time and resource pressure, thus alternative methods of delivery should be assessed for feasibility and efficacy. Larger trials of longer duration are needed to confirm these findings and determine the sustained effect of sleep education on sleep behavior and its impact on health and psychosocial outcomes. A commentary on this article appears in this issue on page 793.

A novel motion sensor-driven control system for FES-assisted walking after spinal cord injury: A pilot study.

Science.gov (United States)

Braz, Gustavo P; Russold, Michael F; Fornusek, Che; Hamzaid, Nur Azah; Smith, Richard M; Davis, Glen M

2016-11-01

This pilot study reports the development of a novel closed-loop (CL) FES-gait control system, which employed a finite-state controller that processed kinematic feedback from four miniaturized motion sensors. This strategy automated the control of knee extension via quadriceps and gluteus stimulation during the stance phase of gait on the supporting leg, and managed the stimulation delivered to the common peroneal nerve (CPN) during swing-phase on the contra-lateral limb. The control system was assessed against a traditional open-loop (OL) system on two sensorimotor 'complete' paraplegic subjects. A biomechanical analysis revealed that the closed-loop control of leg swing was efficient, but without major advantages compared to OL. CL automated the control of knee extension during the stance phase of gait and for this reason was the method of preference by the subjects. For the first time, a feedback control system with a simplified configuration of four miniaturized sensors allowed the addition of instruments to collect the data of multiple physiological and biomechanical variables during FES-evoked gait. In this pilot study of two sensorimotor complete paraplegic individuals, CL ameliorated certain drawbacks of current OL systems - it required less user intervention and accounted for the inter-subject differences in their stimulation requirements. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

‘Putting Life in Years’ (PLINY) telephone friendship groups research study: pilot randomised controlled trial

Science.gov (United States)

2014-01-01

Background Loneliness in older people is associated with poor health-related quality of life (HRQoL). We undertook a parallel-group randomised controlled trial to evaluate the effectiveness and cost-effectiveness of telephone befriending for the maintenance of HRQoL in older people. An internal pilot tested the feasibility of the trial and intervention. Methods Participants aged >74 years, with good cognitive function, living independently in one UK city were recruited through general practices and other sources, then randomised to: (1) 6 weeks of short one-to-one telephone calls, followed by 12 weeks of group telephone calls with up to six participants, led by a trained volunteer facilitator; or (2) a control group. The main trial required the recruitment of 248 participants in a 1-year accrual window, of whom 124 were to receive telephone befriending. The pilot specified three success criteria which had to be met in order to progress the main trial to completion: recruitment of 68 participants in 95 days; retention of 80% participants at 6 months; successful delivery of telephone befriending by local franchise of national charity. The primary clinical outcome was the Short Form (36) Health Instrument (SF-36) Mental Health (MH) dimension score collected by telephone 6 months following randomisation. Results We informed 9,579 older people about the study. Seventy consenting participants were randomised to the pilot in 95 days, with 56 (80%) providing valid primary outcome data (26 intervention, 30 control). Twenty-four participants randomly allocated to the research arm actually received telephone befriending due to poor recruitment and retention of volunteer facilitators. The trial was closed early as a result. The mean 6-month SF-36 MH scores were 78 (SD 18) and 71 (SD 21) for the intervention and control groups, respectively (mean difference, 7; 95% CI, -3 to 16). Conclusions Recruitment and retention of participants to a definitive trial with a

Selective serotonin reuptake inhibitors and gastrointestinal bleeding: a case-control study.

Directory of Open Access Journals (Sweden)

Alfonso Carvajal

Full Text Available BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs have been associated with upper gastrointestinal (GI bleeding. Given their worldwide use, even small risks account for a large number of cases. This study has been conducted with carefully collected information to further investigate the relationship between SSRIs and upper GI bleeding. METHODS: We conducted a case-control study in hospitals in Spain and in Italy. Cases were patients aged ≥18 years with a primary diagnosis of acute upper GI bleeding diagnosed by endoscopy; three controls were matched by sex, age, date of admission (within 3 months and hospital among patients who were admitted for elective surgery for non-painful disorders. Exposures to SSRIs, other antidepressants and other drugs were defined as any use of these drugs in the 7 days before the day on which upper gastrointestinal bleeding started (index day. RESULTS: 581 cases of upper GI bleeding and 1358 controls were considered eligible for the study; no differences in age or sex distribution were observed between cases and controls after matching. Overall, 4.0% of the cases and 3.3% of controls used an SSRI antidepressant in the week before the index day. No significant risk of upper GI bleeding was encountered for SSRI antidepressants (adjusted odds ratio, 1.06, 95% CI, 0.57-1.96 or for whichever other grouping of antidepressants. CONCLUSIONS: The results of this case-control study showed no significant increase in upper GI bleeding with SSRIs and provide good evidence that the magnitude of any increase in risk is not greater than 2.

Integrated care pilot in north west London: a mixed methods evaluation

Directory of Open Access Journals (Sweden)

Natasha Curry

2013-07-01

Full Text Available Introduction: This paper provides the results of a year-long evaluation of a large-scale integrated care pilot in North West London. The pilot aimed to integrate care across primary, acute, community, mental health and social care for people with diabetes and those over 75 years through: care planning; multidisciplinary case reviews; information sharing; and project management support.   Methods: The evaluation team conducted qualitative studies of change at organisational, clinician, and patient levels (using interviews, focus groups and a survey; and quantitative analysis of change in service use and patient-level clinical outcomes (using patient-level data sets and a matched control study.  Results: The pilot had successfully engaged provider organisations, created a shared strategic vision and established governance structures. However, engagement of clinicians was variable and there was no evidence to date of significant reductions in emergency admissions. There was some evidence of changes in care processes. Conclusion: Although the pilot has demonstrated the beginnings of large-scale change, it remains in the early stages and faces significant challenges as it seeks to become sustainable for the longer term. It is critical that NHS managers and clinicians have realistic expectations of what can be achieved in a relatively short period of time.

Integrated care pilot in north west London: a mixed methods evaluation

Directory of Open Access Journals (Sweden)

Natasha Curry

2013-07-01

Full Text Available Introduction: This paper provides the results of a year-long evaluation of a large-scale integrated care pilot in North West London. The pilot aimed to integrate care across primary, acute, community, mental health and social care for people with diabetes and those over 75 years through: care planning; multidisciplinary case reviews; information sharing; and project management support.    Methods: The evaluation team conducted qualitative studies of change at organisational, clinician, and patient levels (using interviews, focus groups and a survey; and quantitative analysis of change in service use and patient-level clinical outcomes (using patient-level data sets and a matched control study.   Results: The pilot had successfully engaged provider organisations, created a shared strategic vision and established governance structures. However, engagement of clinicians was variable and there was no evidence to date of significant reductions in emergency admissions. There was some evidence of changes in care processes.   Conclusion: Although the pilot has demonstrated the beginnings of large-scale change, it remains in the early stages and faces significant challenges as it seeks to become sustainable for the longer term. It is critical that NHS managers and clinicians have realistic expectations of what can be achieved in a relatively short period of time.

External validity of individual differences in multiple cue probability learning: The case of pilot training

Directory of Open Access Journals (Sweden)

Nadine Matton

2013-09-01

Full Text Available Individuals differ in their ability to deal with unpredictable environments. Could impaired performances on learning an unpredictable cue-criteria relationship in a laboratory task be associated with impaired learning of complex skills in a natural setting? We focused on a multiple-cue probability learning (MCPL laboratory task and on the natural setting of pilot training. We used data from three selection sessions and from the three corresponding selected pilot student classes of a national airline pilot selection and training system. First, applicants took an MCPL task at the selection stage (N=556; N=701; N=412. Then, pilot trainees selected from the applicant pools (N=44; N=60; N=28 followed the training for 2.5 to 3 yrs. Differences in final MCPL performance were associated with pilot training difficulties. Indeed, poor MCPL performers experienced almost twice as many pilot training difficulties as better MCPL performers (44.0% and 25.0%, respectively.

Case-control study of mesothelioma in the shipyard industry

International Nuclear Information System (INIS)

Correa-Villasenor, A.

1987-01-01

A nested case-control study was undertaken to investigate the relationship between occupational exposures to asbestos and low-level gamma radiation and mesothelioma. One hundred nineteen cases and four hundred fifty-two latency-matched controls were selected. Analyses were conducted using the conditional maximum likelihood estimate of the odds ratio and conditional logistic regression for matched sets. The results from the analyses revealed a relationship between asbestos exposure and mesothelioma; the strength of this relationship increased with the intensity and duration of the asbestos exposure. Exposure to low-level gamma radiation was also associated with an increased risk of mesothelioma. There was no interaction between asbestos and radiation. Shipyard employment in non-asbestos jobs and male gender were also found to be associated with mesothelioma

Performance of statistical process control methods for regional surgical site infection surveillance: a 10-year multicentre pilot study.

Science.gov (United States)

Baker, Arthur W; Haridy, Salah; Salem, Joseph; Ilieş, Iulian; Ergai, Awatef O; Samareh, Aven; Andrianas, Nicholas; Benneyan, James C; Sexton, Daniel J; Anderson, Deverick J

2017-11-24

Traditional strategies for surveillance of surgical site infections (SSI) have multiple limitations, including delayed and incomplete outbreak detection. Statistical process control (SPC) methods address these deficiencies by combining longitudinal analysis with graphical presentation of data. We performed a pilot study within a large network of community hospitals to evaluate performance of SPC methods for detecting SSI outbreaks. We applied conventional Shewhart and exponentially weighted moving average (EWMA) SPC charts to 10 previously investigated SSI outbreaks that occurred from 2003 to 2013. We compared the results of SPC surveillance to the results of traditional SSI surveillance methods. Then, we analysed the performance of modified SPC charts constructed with different outbreak detection rules, EWMA smoothing factors and baseline SSI rate calculations. Conventional Shewhart and EWMA SPC charts both detected 8 of the 10 SSI outbreaks analysed, in each case prior to the date of traditional detection. Among detected outbreaks, conventional Shewhart chart detection occurred a median of 12 months prior to outbreak onset and 22 months prior to traditional detection. Conventional EWMA chart detection occurred a median of 7 months prior to outbreak onset and 14 months prior to traditional detection. Modified Shewhart and EWMA charts additionally detected several outbreaks earlier than conventional SPC charts. Shewhart and SPC charts had low false-positive rates when used to analyse separate control hospital SSI data. Our findings illustrate the potential usefulness and feasibility of real-time SPC surveillance of SSI to rapidly identify outbreaks and improve patient safety. Further study is needed to optimise SPC chart selection and calculation, statistical outbreak detection rules and the process for reacting to signals of potential outbreaks. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights

Hypothyroidism among SLE patients: Case-control study.

Science.gov (United States)

Watad, Abdulla; Mahroum, Naim; Whitby, Aaron; Gertel, Smadar; Comaneshter, Doron; Cohen, Arnon D; Amital, Howard

2016-05-01

The prevalence of hypothyroidism in SLE patients varies considerably and early reports were mainly based on small cohorts. To investigate the association between SLE and hypothyroidism. Patients with SLE were compared with age and sex-matched controls regarding the proportion of hypothyroidism in a case-control study. Chi-square and t-tests were used for univariate analysis and a logistic regression model was used for multivariate analysis. The study was performed utilizing the medical database of Clalit Health Services. The study included 5018 patients with SLE and 25,090 age and sex-matched controls. The proportion of hypothyroidism in patients with SLE was increased compared with the prevalence in controls (15.58% and 5.75%, respectively, Phypothyroidism (odds ratio 2.644, 95% confidence interval 2.405-2.908). Patients with SLE have a greater proportion of hypothyroidism than matched controls. Therefore, physicians treating patients with SLE should be aware of the possibility of thyroid dysfunction. Copyright © 2016 Elsevier B.V. All rights reserved.

Pilot cluster randomised controlled trial of flooring to reduce injuries from falls in elderly care units: study protocol.

Science.gov (United States)

Drahota, Amy; Gal, Diane; Windsor, Julie; Dixon, Simon; Udell, Julie; Ward, Derek; Soilemezi, Dia; Dean, Taraneh; Severs, Martin

2011-12-01

Falls are an issue disproportionately affecting older people who are at increased risk of falls and injury. This protocol describes a pilot study investigating shock-absorbing flooring for fall-related injuries in wards for older people. To inform future research by evaluating fall-related injuries on the intervention and existing flooring, assessing the sustainability of the flooring in ward environments, estimating the cost-effectiveness of the floor and assessing how the floor affects patients and other users. This study uses mixed methods a pilot cluster randomised controlled trial, observation via mechanical testing and interviews. Eight participating wards (clusters) are randomised using a computer-generated list. No blinding is incorporated into the study. Each site has a baseline period of approximately 6 months. Then, four sites receive the intervention floor, while four continue using standard floors. Sites are then followed up for approximately 1 year. Any person admitted to a bed in the 'study area' of a participating ward can be entered into the trial. Orientated patients, visitors and any hospital staff who use the floor in a study area are eligible for inclusion in an interview. An 8.3 mm thick vinyl floor covering with polyvinyl chloride foam backing (Tarkett Omnisports EXCEL). The primary outcome is fall-related injuries. Severity of injuries, falls, cost-effectiveness, user views and mechanical performance (shock absorbency and slip resistance) are also being assessed.

Pilot Convective Weather Decision Making in En Route Airspace

Science.gov (United States)

Wu, Shu-Chieh; Gooding, Cary L.; Shelley, Alexandra E.; Duong, Constance G.; Johnson, Walter W.

2012-01-01

The present research investigates characteristics exhibited in pilot convective weather decision making in en route airspace. In a part-task study, pilots performed weather avoidance under various encounter scenarios. Results showed that the margins of safety that pilots maintain from storms are as fluid as deviation decisions themselves.

Conflict Resolution Automation and Pilot Situation Awareness

Science.gov (United States)

Dao, Arik-Quang V.; Brandt, Summer L.; Bacon, Paige; Kraut, Josh; Nguyen, Jimmy; Minakata, Katsumi; Raza, Hamzah; Rozovski, David; Johnson, Walter W.

2010-01-01

This study compared pilot situation awareness across three traffic management concepts. The Concepts varied in terms of the allocation of traffic avoidance responsibility between the pilot on the flight deck, the air traffic controllers, and a conflict resolution automation system. In Concept 1, the flight deck was equipped with conflict resolution tools that enable them to fully handle the responsibility of weather avoidance and maintaining separation between ownship and surrounding traffic. In Concept 2, pilots were not responsible for traffic separation, but were provided tools for weather and traffic avoidance. In Concept 3, flight deck tools allowed pilots to deviate for weather, but conflict detection tools were disabled. In this concept pilots were dependent on ground based automation for conflict detection and resolution. Situation awareness of the pilots was measured using online probes. Results showed that individual situation awareness was highest in Concept 1, where the pilots were most engaged, and lowest in Concept 3, where automation was heavily used. These findings suggest that for conflict resolution tasks, situation awareness is improved when pilots remain in the decision-making loop.

Importance of Multifaceted Approaches in Infection Control: A Practical Experience from an Outbreak Investigation.

Directory of Open Access Journals (Sweden)

Nina Katharina Stock

Full Text Available This study presents the results of a multidisciplinary, nosocomial MRSA outbreak investigation in an 8-bed medical intensive care unit (ICU. The identification of seven MRSA positive patients in the beginning of 2014 led to the closure of the ward for several weeks. A multidisciplinary, retrospective investigation was initiated in order to identify the reason and the source for the outbreak, describe MRSA transmission in the department and identify limitations in infection control.The investigation comprised an epidemiological description of MRSA cases from 2012 to 2014 and a characterization of MRSA isolates, including phage-, spa- and PFGE-typing. Additionally, MRSA screening was performed from the hospital staff and the environment. To identify the reason for the outbreak, work-related, psychological and behavioral factors were investigated by impartial audits and staff interviews.Thirty-one MRSA cases were registered during the study period, and 36 isolates were investigated. Molecular typing determined the outbreak strain (phage type 54/812, PFGE type A4, spa type t003 and identified the probable index case. Nasal carriage in one employee and a high environmental contamination with the outbreak strain was documented. Important gaps in nursing procedures and general management were identified. Elevated stress levels and communication problems preceded the outbreak. Compliance with hand hygiene and isolation procedures was evaluated as appropriate.This study demonstrates the complexity of controlling hospital-associated infections. The combined use of different typing methods is beneficial for outbreak investigations. Psychological, behavioral and other work-related factors have an important impact on the spread of nosocomial pathogens. These factors should be addressed and integrated in routine infection control practice.

Acupuncture in the treatment of rheumatoid arthritis: a double-blind controlled pilot study

Directory of Open Access Journals (Sweden)

Zhang Lang

2007-11-01

Full Text Available Abstract Background In planning a randomized controlled trial of acupuncture, we conducted a pilot study using validated outcome measures to assess the feasibility of the protocol, and to obtain preliminary data on efficacy and tolerability of 3 different forms of acupuncture treatment as an adjunct for the treatment of chronic pain in patients with Rheumatoid arthritis (RA. Methods The study employs a randomized, prospective, double-blind, placebo-controlled trial to evaluate the effect of electroacupuncture (EA, traditional Chinese acupuncture (TCA and sham acupuncture (Sham in patients with RA. All patients received 20 sessions over a period of 10 weeks. Six acupuncture points were chosen. Primary outcome is the changes in the pain score. Secondary outcomes included the changes in the ACR core disease measures, DAS 28 score and the number of patients who achieved ACR 20 at week 10. Results From 80 eligible patients, 36 patients with mean age of 58 ± 10 years and disease duration of 9.3 ± 6.4 years were recruited. Twelve patients were randomized to each group. Twelve, 10 and 7 patients from the EA, TCA and Sham group respectively completed the study at 20 weeks (p Conclusion This pilot study has allowed a number of recommendations to be made to facilitate the design of a large-scale trial, which in turn will help to clarify the existing evidence base on acupuncture for RA. Trial registration ClinicalTrials.gov NCT00404443

Music for surgical abortion care study: a randomized controlled pilot study.

Science.gov (United States)

Wu, Justine; Chaplin, William; Amico, Jennifer; Butler, Mark; Ojie, Mary Jane; Hennedy, Dina; Clemow, Lynn

2012-05-01

The study objective was to explore the effect of music as an adjunct to local anesthesia on pain and anxiety during first-trimester surgical abortion. Secondary outcomes included patient satisfaction and coping. We conducted a randomized controlled pilot study of 26 women comparing music and local anesthesia to local anesthesia alone. We assessed pain, anxiety and coping with 11-point verbal numerical scales. Patient satisfaction was measured via a 4-point Likert scale. In the music group, we noted a trend toward a faster decline in anxiety postprocedure (p=.065). The music group reported better coping than the control group (mean±S.D., 8.5±2.3 and 6.2±2.8, respectively; pMusic as an adjunct to local anesthesia during surgical abortion is associated with a trend toward less anxiety postprocedure and better coping while maintaining high patient satisfaction. Music does not appear to affect abortion pain. Copyright © 2012 Elsevier Inc. All rights reserved.

Surgery versus Active Monitoring in Intermittent Exotropia (SamExo: study protocol for a pilot randomised controlled trial

Directory of Open Access Journals (Sweden)

Buck Deborah

2012-10-01

Full Text Available Abstract Background Childhood intermittent exotropia [X(T] is a type of strabismus (squint in which one eye deviates outward at times, usually when the child is tired. It may progress to a permanent squint, loss of stereovision and/or amblyopia (reduced vision. Treatment options for X(T include eye patches, glasses, surgery and active monitoring. There is no consensus regarding how this condition should be managed, and even when surgery is the preferred option clinicians disagree as to the optimal timing. Reports on the natural history of X(T are limited, and there is no randomised controlled trial (RCT evidence on the effectiveness or efficiency of surgery compared with active monitoring. The SamExo (Surgery versus Active Monitoring in Intermittent Exotropia pilot study has been designed to test the feasibility of such a trial in the UK. Methods Design: an external pilot patient randomised controlled trial. Setting: four UK secondary ophthalmology care facilities at Newcastle NHS Hospitals Foundation Trust, Sunderland Eye Infirmary, Moorfields Eye Hospital and York NHS Trust. Participants: children aged between 6 months and 16 years referred with suspected and subsequently diagnosed X(T. Recruitment target is a total of 144 children over a 9-month period, with 120 retained by 9-month outcome visit. Randomisation: permuted blocks stratified by collaborating centre, age and severity of X(T. Interventions: initial clinical assessment; randomisation (eye muscle surgery or active monitoring; 3-, 6- and 9-month (primary outcome clinical assessments; participant/proxy completed questionnaire covering time and travel costs, health services use and quality of life (Intermittent Exotropia Questionnaire; qualitative interviews with parents to establish reasons for agreeing or declining participation in the pilot trial. Outcomes: recruitment and retention rates; nature and extent of participation bias; nature and extent of biases arising from crossover or

Influence of inhomogeneous static magnetic field-exposure on patients with erosive gastritis: a randomized, self- and placebo-controlled, double-blind, single centre, pilot study.

Science.gov (United States)

Juhász, Márk; Nagy, Viktor L; Székely, Hajnal; Kocsis, Dorottya; Tulassay, Zsolt; László, János F

2014-09-06

This pilot study was devoted to the effect of static magnetic field (SMF)-exposure on erosive gastritis. The randomized, self- and placebo-controlled, double-blind, pilot study included 16 patients of the 2nd Department of Internal Medicine, Semmelweis University diagnosed with erosive gastritis. The instrumental analysis followed a qualitative (pre-intervention) assessment of the symptoms by the patient: lower heartburn (in the ventricle), upper heartburn (in the oesophagus), epigastric pain, regurgitation, bloating and dry cough. Medical diagnosis included a double-line upper panendoscopy followed by 30 min local inhomogeneous SMF-exposure intervention at the lower sternal region over the stomach with peak-to-peak magnetic induction of 3 mT and 30 mT m(-1) gradient at the target site. A qualitative (post-intervention) assessment of the same symptoms closed the examination. Sham- or SMF-exposure was used in a double-blind manner. The authors succeeded in justifying the clinically and statistically significant beneficial effect of the SMF- over sham-exposure on the symptoms of erosive gastritis, the average effect of inhibition was 56% by p = 0.001, n = 42 + 96. This pilot study was aimed to encourage gastroenterologists to test local, inhomogeneous SMF-exposure on erosive gastritis patients, so this intervention may become an evidence-based alternative or complementary method in the clinical use especially in cases when conventional therapy options are contraindicated. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Identification and medical utilization of incident cases of alcohol dependence: A population-based case-control study.

Science.gov (United States)

Pan, Chun-Hung; Li, Min-Shan; Yang, Tien-Wey; Huang, Ming-Chyi; Su, Sheng-Shiang; Hung, Yen-Ni; Chen, Chiao-Chicy; Kuo, Chian-Jue

2018-05-05

Patients with alcohol dependence (AD) often seek help from medical professionals due to alcohol-related diseases, but the overall distribution of medical specialties identifying new AD cases is unclear. We investigated how such cases were identified and how medical resources were utilized before the identification of AD in a nationwide cohort. We enrolled a population-based cohort (N = 1,000,000) using the National Health Insurance Research Database of Taiwan; 8181 cases with incident AD were retrieved between January 1, 2000, and December 31, 2010. For this nested case-control study, four controls were matched for age and sex with each case based on risk-set sampling. We measured various dimensions of medical utilization before AD was diagnosed, including department visited, physical comorbidity, and medication used. Conditional logistic regression was used for estimating the variables associated with AD. Patients living in less urbanized areas who were unemployed were more likely to develop AD. The highest proportions (34.2%) of AD cases were identified in the internal medicine department, followed by the emergency (22.3%) and psychiatry (18.7%) departments. AD patients had a higher risk of comorbid chronic hepatic disease (adjusted RR = 2.72, p identification of AD than controls. AD patients also had greater numbers of hospital admissions than controls, including non-psychiatric and psychiatric hospitalizations. Outpatient visit numbers were similar for AD patients and controls. The findings indicate that clinicians providing care in diverse medical settings should be prepared to screen for unhealthy alcohol use and to mitigate its detrimental effects. Copyright © 2018 Elsevier B.V. All rights reserved.

Pilot implementation Driven by Effects Specifications and Formative Usability Evaluation

DEFF Research Database (Denmark)

Barlach, Anders; Hertzum, Morten; Simonsen, Jesper

2013-01-01

This chapter reports on the usability-engineering work performed throughout the pilot implementation of an Electronic Healthcare Record (EHR). The case describes and analyzes the use of pilot implementations to formatively evaluate whether the usability of the EHR meets the effects specified for ...

NEREDA Pilot Studies 2003 - 2010; NEREDA Pilotonderzoeken 2003 - 2010

Energy Technology Data Exchange (ETDEWEB)

Berkhof, D.; De Bruin, B.; Kerstholt, M.; Kraan, R.; Miska, V.; Peeters, T.; Van der Roest, H.; Verschoor, J. [DHV, Amersfoort (Netherlands); De Kreuk, M.; Van Loosdrecht, M. [Technische Universiteit Delft TUD, Delft (Netherlands)

2010-10-15

Since the nineties of last century research has been conducted on the development of the aerobic granular sludge technology for wastewater treatment. A first STOWA pilot research project was executed at Ede, Netherlands. In 2005 a technological breakthrough was accomplished and was the starting sign for a broader national development program (NNOP). Next to STOWA, Delft University of Delft and DHV, six Waterboards are involved within this development program. Main goal of the NNOP is to develop a new competitive biological wastewater treatment technology (Nereda). After the Ede project additional pilot research projects were conducted at four locations in the Netherlands. Within these pilot research projects the following aspects were investigated: granulation on different wastewater types; stability of granular sludge; optimization of nitrogen and phosphate removal, especially during winter time; control of effluent suspended solids concentration; and obtain technological design parameters for full scale WWTPs (waste water treatment plants) [Dutch] In dit rapport staan de resultaten beschreven van de tussen 2003 en 2010 uitgevoerde pilots met de aeroob-korrelslibtechnologie Nereda. Dit is een nieuwe zuiveringstechnologie waarbij het reinigende actief slib geen vlokken maar korrels vormt. Hierdoor bezinkt het slib sneller en makkelijker. De technologie wordt gekenmerkt door hoge zuiveringsrendementen, weinig ruimtebeslag (voor bezinking) en relatief lage energiekosten. De resultaten van de pilots zijn dermate goed, dat drie van de vijf deelnemende waterschappen hebben besloten om 1 van hun rwzi's (rioolwaterzuiveringsinstallaties) aan te passen op basis van de Nereda-technologie.

Pain as an indication for rib fixation: a bi-institutional pilot study.

Science.gov (United States)

de Moya, Marc; Bramos, Thanos; Agarwal, Suresh; Fikry, Karim; Janjua, Sumbal; King, David R; Alam, Hasan B; Velmahos, George C; Burke, Peter; Tobler, William

2011-12-01

In trauma patients, open reduction and internal fixation of rib fractures remain controversial. We hypothesized that patients who have open reduction and internal fixation of rib fractures would experience less pain compared with controls and thus require fewer opiates. Further, we hypothesized that improved pain control would result in fewer pulmonary complications and decreased length of stay. This is a retrospective bi-institutional matched case-control study. Cases were matched 1:2 by age, injury severity Score, chest abbreviated injury severity score, head abbreviated injury severity score, pulmonary contusion score, and number of fractured ribs. The daily total doses of analgesic drugs were converted to equianalgesic intravenous morphine doses, and the primary outcome was inpatient narcotic administration. Sixteen patients between July 2005 and June 2009 underwent rib fixation in 5 ± 3 days after injury using an average of 3 (1-5) metallic plates. Morphine requirements decreased from 110 mg ± 98 mg preoperatively to 63 ± 57 mg postoperatively (p = 0.01). There were no significant differences between cases and controls in the mean morphine dose (79 ± 63 vs. 76 ± 55 mg, p = 0.65), hospital stay (18 ± 12 vs. 16 ± 11 days, p = 0.67), intensive care unit stay (9 ± 8 vs. 7 ± 10 days, p = 0.75), ventilation days (7 ± 8 vs. 6 ± 10, p = 0.44), and pneumonia rates (31% vs. 38%, p = 0.76). The need for analgesia was significantly reduced after rib fixation in patients with multiple rib fractures. However, no difference in outcomes was observed when these patients were compared with matched controls in this pilot study. Further study is required to investigate these preliminary findings.

Navigating the Road to Recovery: Assessment of the Coordination, Communication, and Financing of the Disaster Case Management Pilot in Louisiana.

Science.gov (United States)

Acosta, Joie; Chandra, Anita; Feeney, Kevin Carter

2011-01-01

In 2009, individuals heavily affected by Hurricanes Katrina and Rita were still in need of social services. The Federal Emergency Management Agency (FEMA) provided funding to the Louisiana Recovery Authority to implement the Disaster Case Management Pilot (DCMP) in order to help people still living in FEMA temporary housing units in April 2009 move to permanent and secure housing and access services. Despite concerted effort by participating agencies, the implementation of the DCMP was fraught with challenges. As a result, the pilot could not be implemented as intended, leaving the needs of many clients not fully met. This article shares details of a study that documents some of the key challenges in coordination, communication, and financing of the program and offers recommendations for future state and FEMA implementation of disaster case management. In light of these challenges, the authors recommend that federal and state governments review the systems used to identify and locate residents in need of disaster case management; these systems performed poorly in the DCMP, making it difficult to appropriately plan services. The stop and start of recovery initiatives led to serious discontinuities in client recovery, so the authors also recommend that federal and state governments consider a single, longer-term recovery initiative that seamlessly acknowledges the stages of human recovery. Improvements in how federal and state governments identify and locate affected residents, consider needs and vulnerabilities in planning, and ensure continuity of services are critical to ensure high-quality disaster case management.

Leap motion controlled videogame-based therapy for rehabilitation of elderly patients with subacute stroke: a feasibility pilot study.

Science.gov (United States)

Iosa, Marco; Morone, Giovanni; Fusco, Augusto; Castagnoli, Marcello; Fusco, Francesca Romana; Pratesi, Luca; Paolucci, Stefano

2015-08-01

The leap motion controller (LMC) is a new optoelectronic system for capturing motion of both hands and controlling a virtual environment. Differently from previous devices, it optoelectronically tracks the fine movements of fingers neither using glows nor markers. This pilot study explored the feasibility of adapting the LMC, developed for videogames, to neurorehabilitation of elderly with subacute stroke. Four elderly patients (71.50 ± 4.51 years old) affected by stroke in subacute phase were enrolled and tested in a cross-over pilot trial in which six sessions of 30 minutes of LMC videogame-based therapy were added on conventional therapy. Measurements involved participation to the sessions, evaluated by means of the Pittsburgh Rehabilitation Participation Scale, hand ability and grasp force evaluated respectively by means of the Abilhand Scale and by means of the dynamometer. Neither adverse effects nor spasticity increments were observed during LMC training. Participation to the sessions was excellent in three patients and very good in one patient during the LMC trial. In this period, patients showed a significantly higher improvement in hand abilities (P = 0.028) and grasp force (P = 0.006). This feasibility pilot study was the first one using leap motion controller for conducting a videogame-based therapy. This study provided a proof of concept that LMC can be a suitable tool even for elderly patients with subacute stroke. LMC training was in fact performed with a high level of active participation, without adverse effects, and contributed to increase the recovery of hand abilities.

Regional ventricular performance and exercise training in children and young adults after repair of tetralogy of Fallot: randomized controlled pilot study.

Science.gov (United States)

Duppen, Nienke; Geerdink, Lianne M; Kuipers, Irene M; Bossers, Sjoerd S M; Koopman, Laurens P; van Dijk, Arie P J; Roos-Hesselink, Jolien W; De Korte, Chris L; Helbing, Willem A; Kapusta, Livia

2015-04-01

Public-health guidelines recommend patients with congenital heart disease to exercise. Studies have shown that patients with congenital heart disease can improve physical exercise capacity. The effect of training on regional ventricular performance has hardly been studied. We performed a pilot study to assess whether an exercise training program would result in adverse changes of regional ventricular performance in patients with corrected tetralogy of Fallot. Multicenter prospective randomized controlled pilot study in patients with tetralogy of Fallot aged 10 to 25 years. A 12-week standardized aerobic dynamic exercise training program (3 one-hour sessions per week) was used. Pre- and post-training cardiopulmonary exercise tests, MRI, and echocardiography, including tissue-Doppler imaging, were performed. Patients were randomized to the exercise group (n=28) or control group (n=20). One patient in the exercise group dropped out. Change in tissue-Doppler imaging parameters was similar in the exercise group and control group (change in right ventricle free wall peak velocity E' exercise group, 0.8±2.6 cm/s; control group, 0.9±4.1; peak velocity A' exercise group, 0.4±2.4 m/s; control group 4.6±18.1 cm/s). This randomized controlled pilot study provides preliminary data suggesting that regional ventricular performance is well maintained during 3-month aerobic dynamic exercise training in children and young adults with repaired tetralogy of Fallot. This information might help patients adhere to current public-health guidelines. URL: http//:www.trialregister.nl. Unique identifier: NTR2731. © 2015 American Heart Association, Inc.

Pollution profiles, health risk of VOCs and biohazards emitted from municipal solid waste transfer station and elimination by an integrated biological-photocatalytic flow system: a pilot-scale investigation.

Science.gov (United States)

Li, Guiying; Zhang, Zhengyong; Sun, Hongwei; Chen, Jiangyao; An, Taicheng; Li, Bing

2013-04-15

Volatile organic compounds (VOCs) and biohazards air pollution in municipal solid waste transfer station were investigated. As compressor working, the concentrations of almost all quantified 14 VOCs (0.32-306.03 μg m(-3)) were much higher than those as compressor off (0-13.31 μg m(-3)). Comparatively, only 3 VOCs with extremely low concentrations could be detected at control area. Total microorganism was 7567 CFU m(-3) as compressor working, which was 1.14 and 6.22 times higher than that of compressor off and control area, respectively. Bacteria were the most abundant microorganism at all three sampling places. At pilot-scale, during whole 60-day treatment, for VOCs, the average removal efficiencies were over 92% after biotrickling filter-photocatalytic (BTF-PC) treatment. Although non-cancer and cancer risks of some VOCs were over the concern level before treatment, almost all VOCs were removed substantially and both potential risks were below the concern after BTF-PC treatment. Additionally, biohazard concentrations decreased dramatically and air quality was purified from polluted to cleanness after PC treatment. All results demonstrated that the integrated technology possessed high removal capacity and long stability for the removal of VOCs and biohazards at a pilot scale. Copyright © 2013 Elsevier B.V. All rights reserved.

Pilot factory - a Condor-based system for scalable Pilot Job generation in the Panda WMS framework

International Nuclear Information System (INIS)

Chiu, Po-Hsiang; Potekhin, Maxim

2010-01-01

The Panda Workload Management System is designed around the concept of the Pilot Job - a 'smart wrapper' for the payload executable that can probe the environment on the remote worker node before pulling down the payload from the server and executing it. Such design allows for improved logging and monitoring capabilities as well as flexibility in Workload Management. In the Grid environment (such as the Open Science Grid), Panda Pilot Jobs are submitted to remote sites via mechanisms that ultimately rely on Condor-G. As our experience has shown, in cases where a large number of Panda jobs are simultaneously routed to a particular remote site, the increased load on the head node of the cluster, which is caused by the Pilot Job submission, may lead to overall lack of scalability. We have developed a Condor-inspired solution to this problem, which is using the schedd-based glidein, whose mission is to redirect pilots to the native batch system. Once a glidein schedd is installed and running, it can be utilized exactly the same way as local schedds and therefore, from the user's perspective, Pilots thus submitted are quite similar to jobs submitted to the local Condor pool.

Application of a pilot control banding tool for risk level assessment and control of nanoparticle exposures.

Science.gov (United States)

Paik, Samuel Y; Zalk, David M; Swuste, Paul

2008-08-01

Control banding (CB) strategies offer simplified solutions for controlling worker exposures to constituents that are found in the workplace in the absence of firm toxicological and exposure data. These strategies may be particularly useful in nanotechnology applications, considering the overwhelming level of uncertainty over what nanomaterials and nanotechnologies present as potential work-related health risks, what about these materials might lead to adverse toxicological activity, how risk related to these might be assessed and how to manage these issues in the absence of this information. This study introduces a pilot CB tool or 'CB Nanotool' that was developed specifically for characterizing the health aspects of working with engineered nanoparticles and determining the level of risk and associated controls for five ongoing nanotechnology-related operations being conducted at two Department of Energy research laboratories. Based on the application of the CB Nanotool, four of the five operations evaluated in this study were found to have implemented controls consistent with what was recommended by the CB Nanotool, with one operation even exceeding the required controls for that activity. The one remaining operation was determined to require an upgrade in controls. By developing this dynamic CB Nanotool within the realm of the scientific information available, this application of CB appears to be a useful approach for assessing the risk of nanomaterial operations, providing recommendations for appropriate engineering controls and facilitating the allocation of resources to the activities that most need them.

Multimodal Pilot Behavior in Multi-Axis Tracking Tasks with Time-Varying Motion Cueing Gains

Science.gov (United States)

Zaal, P. M. T; Pool, D. M.

2014-01-01

In a large number of motion-base simulators, adaptive motion filters are utilized to maximize the use of the available motion envelope of the motion system. However, not much is known about how the time-varying characteristics of such adaptive filters affect pilots when performing manual aircraft control. This paper presents the results of a study investigating the effects of time-varying motion filter gains on pilot control behavior and performance. An experiment was performed in a motion-base simulator where participants performed a simultaneous roll and pitch tracking task, while the roll and/or pitch motion filter gains changed over time. Results indicate that performance increases over time with increasing motion gains. This increase is a result of a time-varying adaptation of pilots' equalization dynamics, characterized by increased visual and motion response gains and decreased visual lead time constants. Opposite trends are found for decreasing motion filter gains. Even though the trends in both controlled axes are found to be largely the same, effects are less significant in roll. In addition, results indicate minor cross-coupling effects between pitch and roll, where a cueing variation in one axis affects the behavior adopted in the other axis.

A pilot scale demonstration of the DWPF process control and product verification strategy

International Nuclear Information System (INIS)

Hutson, N.D.; Jantzen, C.M.; Beam, D.C.

1992-01-01

The Defense Waste Processing Facility (DWPF) has been designed and constructed to immobilize Savannah River Site high level liquid waste within a durable borosilicate glass matrix for permanent storage. The DWPF will be operated to produce a glass product which must meet a number of product property constraints which are dependent upon the final product composition. During actual operations, the DWPF will control the properties of the glass product by the controlled blending of the waste streams with a glass-forming frit to produce the final melter feed slurry. The DWPF will verify control of the glass product through analysis of vitrified samples of slurry material. In order to demonstrate the DWPF process control and product verification strategy, a pilot-scale vitrification research facility was operated in three discrete batches using simulated DWPF waste streams. All of the DWPF process control methodologies were followed and the glass product from each experiment was leached according to the Product Consistency Test. In this paper results of the campaign are summarized

Overcoming Barriers to Disseminating Exposure Therapies for Anxiety Disorders: A Pilot Randomized Controlled Trial of Training Methods

OpenAIRE

Harned, Melanie S.; Dimeff, Linda A.; Woodcock, Eric A.; Skutch, Julie M.

2011-01-01

The present study evaluated methods for training mental health providers (N=46) in exposure therapies (ETs) for anxiety disorders. A pilot randomized controlled trial compared: 1) an interactive, multimedia online training (ET OLT), 2) the ET OLT plus a brief Motivational Interviewing-based intervention (ET OLT + MI), and 3) a placebo control OLT. Assessments were completed at baseline, post-training, and one week following training. Both ET OLT and ET OLT + MI received high satisfaction rati...

TASKILLAN II - Pilot strategies for workload management

Science.gov (United States)

Segal, Leon D.; Wickens, Christopher D.

1990-01-01

This study focused on the strategies used by pilots in managing their workload level, and their subsequent task performance. Sixteen licensed pilots flew 42 missions on a helicopter simulation, and were evaluated on their performance of the overall mission, as well as individual tasks. Pilots were divided in four groups, defined by the presence or absence of scheduling control over tasks and the availability of intelligence concerning the type and stage of difficulties imposed during the flight. Results suggest that intelligence supported strategies that yielded significant higher performance levels, while scheduling control seemed to have no impact on performance. Both difficulty type and the stage of difficulty impacted performance significantly, with strongest effects for time stresss and difficulties imposed late in the flight.

Abnormal Cortical Plasticity in Youth with Autism Spectrum Disorder: A Transcranial Magnetic Stimulation Case-Control Pilot Study.

Science.gov (United States)

Pedapati, Ernest V; Gilbert, Donald L; Erickson, Craig A; Horn, Paul S; Shaffer, Rebecca C; Wink, Logan K; Laue, Cameron S; Wu, Steve W

2016-09-01

This case-control study investigated the use of a low-intensity repetitive transcranial magnetic stimulation (rTMS) protocol to measure motor cortex (M1) plasticity in youth with autism spectrum disorder (ASD) compared with typically developing children (TDC). We hypothesized that impairments in long-term potentiation-like properties represent a neurophysiological biomarker of abnormal cortical function in ASD. We studied youth with ASD aged 11-18 years and matched controls (TDC). Intermittent theta burst stimulation (iTBS) was delivered to the dominant M1 at an intensity of 70% of resting motor threshold. Suprathreshold single-pulse TMS was performed to compare amplitudes of motor-evoked potentials (MEP) measured from surface electromyography electrodes on a target muscle before (20 pulses) and after (10 pulses/time point) iTBS at predefined timepoints (up to 30 minutes) to measure any potentiation effects. A linear mixed model was used to examine group differences in MEP amplitudes over time following iTBS. Nine youth with ASD (mean age 15.6; 7 males; 6 right-hand dominant) and 9 TDC (mean age 14.5; 5 males; 9 right-hand dominant) participated. All subjects tolerated the procedure well. Both groups had a mean increase in excitability after iTBS for 30 minutes; however, the time course of excitability changes differed (F9,144 = 2.05; p = 0.038). Post-hoc testing identified a significant decrease in amplitude of the ASD group at 20 minutes following iTBS compared with the TDC after correcting for multiple comparisons. In this study, we demonstrate early evidence for a potential physiological biomarker of cortical plasticity in youth with ASD using a rapid low-intensity rTMS protocol with a discriminate measure at 20 minutes following stimulation. The procedure was well tolerated by all 18 participants. Future work will include modification of the protocol to improve the ability to distinguish subtypes of ASD based on behavioral and cognitive testing.

Controlling the COD removal of an A-stage pilot study with instrumentation and automatic process control.

Science.gov (United States)

Miller, Mark W; Elliott, Matt; DeArmond, Jon; Kinyua, Maureen; Wett, Bernhard; Murthy, Sudhir; Bott, Charles B

2017-06-01

The pursuit of fully autotrophic nitrogen removal via the anaerobic ammonium oxidation (anammox) pathway has led to an increased interest in carbon removal technologies, particularly the A-stage of the adsorption/bio-oxidation (A/B) process. The high-rate operation of the A-stage and lack of automatic process control often results in wide variations of chemical oxygen demand (COD) removal that can ultimately impact nitrogen removal in the downstream B-stage process. This study evaluated the use dissolved oxygen (DO) and mixed liquor suspended solids (MLSS) based automatic control strategies through the use of in situ on-line sensors in the A-stage of an A/B pilot study. The objective of using these control strategies was to reduce the variability of COD removal by the A-stage and thus the variability of the effluent C/N. The use of cascade DO control in the A-stage did not impact COD removal at the conditions tested in this study, likely because the bulk DO concentration (>0.5 mg/L) was maintained above the half saturation coefficient of heterotrophic organisms for DO. MLSS-based solids retention time (SRT) control, where MLSS was used as a surrogate for SRT, did not significantly reduce the effluent C/N variability but it was able to reduce COD removal variation in the A-stage by 90%.

Health issues in the Arab American community. Male infertility in Lebanon: a case-controlled study.

Science.gov (United States)

Kobeissi, Loulou; Inhorn, Marcia C

2007-01-01

The impact of risk factors, such as consanguinity and familial clustering, reproductive infections, traumas, and diseases, lifestyle factors and occupational and war exposures on male infertility, was investigated in a case-controlled study conducted in Lebanon. One-hundred-twenty males and 100 controls of Lebanese, Syrian or Lebanese-Palestinian descents were selected from two in-vitro fertilization (IVF) clinics located in Beirut, Lebanon. All cases suffered from impaired sperm count and function, according to World Health Organization guidelines for semen analysis. Controls were the fertile husbands of infertile women. Data were collected using a semi-structured interview, laboratory blood testing and the results of the most recent semen analysis. Univariate, bivariate and multivariate logistic regression analyses were used for data analysis, along with checks for effect modification and control of confounders. Consanguinity and the familial clustering of male infertility cases, as well as reproductive illnesses and war exposures were independently significant risk factors for male infertility. The odds of having infertility problems in the immediate family were 2.6 times higher in cases than controls. The odds of reproductive illness were 2 times higher in cases than controls. The odds of war exposures were 1.57 times higher in cases than controls. Occupational exposures, such as smoking and caffeine intake, were not shown to be important risk factors. This case-controlled study highlights the importance of investigating the etiology of male infertility in Middle Eastern communities. It suggests the need to expand research on male reproductive health in the Middle East in order to improve the prevention and management of male infertility and other male reproductive health problems.

Alcohol and Difficulty Conceiving in the SUN Cohort: A Nested Case-Control Study

OpenAIRE

Cristina Lopez-del Burgo; Alfredo Gea; Jokin de Irala; Miguel A. Martínez-González; Jorge E. Chavarro; Estefania Toledo

2015-01-01

The role of alcohol on fertility remains unclear. We aimed to investigate the association between alcohol and specific alcoholic beverages consumption and the risk of difficulty getting pregnant. We used a case-control study nested within the Seguimiento Universidad de Navarra (SUN) cohort, a prospective, dynamic and multipurpose cohort of 21,705 Spanish university graduates, followed biennially with mailed questionnaires. We identified 686 case-control pairs, matched for age and time in the ...

Practical experience of backwashing with SWRO permeate for UF fouling control

KAUST Repository

Li, Sheng; Heijman, Sebastiaan G J; Verberk, J. Q J C; Amy, Gary L.; Van Dijk, Johannis C.

2013-01-01

Effectiveness of seawater reverse osmosis (SWRO) permeate backwash on fouling control of seawater ultrafiltration was investigated at a pilot scale. A standard membrane module was used in this pilot to represent full-scale desalination plants. Results of the pilot show a good reproducibility. When the UF permeate was used for backwash, the frequency of chemically enhanced backwash (CEB) was around once per day. However, results of the pilot show that SWRO permeate backwashing could significantly reduce the CEB frequency. © 2013 Desalination Publications.

NSTAR Smart Grid Pilot

Energy Technology Data Exchange (ETDEWEB)

Rabari, Anil [NSTAR Electric, Manchester, NH (United States); Fadipe, Oloruntomi [NSTAR Electric, Manchester, NH (United States)

2014-03-31

NSTAR Electric & Gas Corporation (“the Company”, or “NSTAR”) developed and implemented a Smart Grid pilot program beginning in 2010 to demonstrate the viability of leveraging existing automated meter reading (“AMR”) deployments to provide much of the Smart Grid functionality of advanced metering infrastructure (“AMI”), but without the large capital investment that AMI rollouts typically entail. In particular, a central objective of the Smart Energy Pilot was to enable residential dynamic pricing (time-of-use “TOU” and critical peak rates and rebates) and two-way direct load control (“DLC”) by continually capturing AMR meter data transmissions and communicating through customer-sited broadband connections in conjunction with a standardsbased home area network (“HAN”). The pilot was supported by the U.S. Department of Energy’s (“DOE”) through the Smart Grid Demonstration program. NSTAR was very pleased to not only receive the funding support from DOE, but the guidance and support of the DOE throughout the pilot. NSTAR is also pleased to report to the DOE that it was able to execute and deliver a successful pilot on time and on budget. NSTAR looks for future opportunities to work with the DOE and others in future smart grid projects.

Feeling safe in the plane: neural mechanisms underlying superior action control in airplane pilot trainees--a combined EEG/MRS study.

Science.gov (United States)

Yildiz, Ali; Quetscher, Clara; Dharmadhikari, Shalmali; Chmielewski, Witold; Glaubitz, Benjamin; Schmidt-Wilcke, Tobias; Edden, Richard; Dydak, Ulrike; Beste, Christian

2014-10-01

In day-to-day life, we need to apply strategies to cascade different actions for efficient unfolding of behavior. While deficits in action cascading are examined extensively, almost nothing is known about the neuronal mechanisms mediating superior performance above the normal level. To examine this question, we investigate action control in airplane pilot trainees. We use a stop-change paradigm that is able to estimate the efficiency of action cascading on the basis of mathematical constraints. Behavioral and EEG data is analyzed along these constraints and integrated with neurochemical data obtained using Magnetic Resonance Spectroscopy (MRS) from the striatal gamma-aminobutyric acid (GABA) -ergic system. We show that high performance in action cascading, as exemplified in airplane pilot trainees, can be driven by intensified attentional processes, circumventing response selection processes. The results indicate that the efficiency of action cascading and hence the speed of responding as well as attentional gating functions are modulated by striatal GABA and Glutamate + Glutamine concentrations. In superior performance in action cascading similar increases in the concentrations of GABA and Glutamate + Glutamine lead to stronger neurophysiological and behavioral effects as compared to subjects with normal performance in action cascading. Copyright © 2014 Wiley Periodicals, Inc.

Guided self-help interventions for mental health disorders in children with neurological conditions: study protocol for a pilot randomised controlled trial.

Science.gov (United States)

Bennett, Sophie; Heyman, Isobel; Coughtrey, Anna; Simmonds, Jess; Varadkar, Sophia; Stephenson, Terence; DeJong, Margaret; Shafran, Roz

2016-11-04

Rates of mental health disorders are significantly greater in children with physical illnesses than in physically well children. Children with neurological conditions, such as epilepsy, are known to have particularly high rates of mental health disorders. Despite this, mental health problems in children with neurological conditions have remained under-recognised and under-treated in clinical settings. Evidence-based guided self-help interventions are efficacious in reducing symptoms of mental health disorders in children, but their efficacy in reducing symptoms of common mental health disorders in children with neurological conditions has not been investigated. We aim to pilot a guided self-help intervention for the treatment of mental health disorders in children with neurological conditions. A pilot randomised controlled trial with 18 patients with neurological conditions and mental health disorders will be conducted. Participants attending specialist neurology clinics at a National UK Children's Hospital will be randomised to receive guided self-help for common mental health disorders or to a 12-week waiting list control. Participants in the treatment group will receive 10 sessions of guided self-help delivered over the telephone. The waiting list control group will receive the intervention after a waiting period of 12 weeks. The primary outcome measure is reduction in symptoms of mental health disorders. Exclusion criteria are limited to those at significant risk of harm to self or others, the presence of primary mental health disorder other than anxiety, depression or disruptive behaviour (e.g. psychosis, eating disorder, obsessive-compulsive disorder) or intellectual disability at a level meaning potential participants would be unable to access the intervention. The study has ethical approval from the Camden and Islington NHS Research Ethics Committee, registration number 14.LO.1353. Results will be disseminated to patients, the wider public, clinicians and

Pilot-scale application of an online VFA sensor for monitoring and control of a manure digester

DEFF Research Database (Denmark)

Boe, Kanokwan; Angelidaki, Irini

2012-01-01

A volatile fatty acids (VFA) sensor based on headspace chromatography was tested for online monitoring and control of a pilot-scale manure digester. The sensor showed satisfying results in terms of sensitivity and reliability for monitoring of the digester. The online VFA and biogas production data...... parameter for optimization, it could not distinguish between the decreases of biogas production from inhibition and from lower organic content in the substrate, which resulted in undesired decreasing of the control gas setpoint when the substrate was diluted. It was necessary to adjust the yield parameter...

TEACCH-based group social skills training for children with high-functioning autism: a pilot randomized controlled trial.

Science.gov (United States)

Ichikawa, Kayoko; Takahashi, Yoshimitsu; Ando, Masahiko; Anme, Tokie; Ishizaki, Tatsuro; Yamaguchi, Hinako; Nakayama, Takeo

2013-10-01

Although social skills training programs for people with high-functioning autism (HFA) are widely practiced, the standardization of curricula, the examination of clinical effectiveness, and the evaluation of the feasibility of future trials have yet to be done in Asian countries. To compensate for this problem, a Japanese pilot randomized controlled trial (RCT) of the Treatment and Education of Autistic and Related Communication Handicapped Children (TEACCH)-based group social skills training for children with HFA and their mothers was conducted. Eleven children with HFA, aged 5-6 years, and their mothers were randomly assigned to the TEACCH program (n=5) or a waiting-list control group (n=6). The program involved comprehensive group intervention and featured weekly 2-hour sessions, totaling 20 sessions over six months. The adaptive behaviors and social reciprocity of the children, parenting stress, and parent-child interactions were assessed using the Strengths and Difficulties Questionnaire (SDQ), Parenting Stress Index (PSI), Beck depression inventory-II (BDI-II), and Interaction Rating Scale (IRS). Through this pilot trial, the intervention and evaluation of the program has been shaped. There were no dropouts from the program and the mothers' satisfaction was high. The outcome measurements improved more in the program group than in the control group, with moderate effect sizes (SDQ, 0.71; PSI, 0.58; BDI-II, 0.40; and IRS, 0.69). This pilot trial also implied that this program is more beneficial for high IQ children and mothers with low stress than for those who are not. We have standardized the TEACCH program, confirmed the feasibility of a future trial, and successfully estimated the positive effect size. These findings will contribute to a larger trial in the future and to forthcoming systematic reviews with meta-analyses. UMIN000004560.

Sage tea-thyme-peppermint hydrosol oral rinse reduces chemotherapy-induced oral mucositis: A randomized controlled pilot study.

Science.gov (United States)

Mutluay Yayla, Ezgi; Izgu, Nur; Ozdemir, Leyla; Aslan Erdem, Sinem; Kartal, Murat

2016-08-01

This pilot study aimed to investigate the preventive effect of sage tea-thyme-peppermint hydrosol oral rinse used in conjunction with basic oral care on chemotherapy-induced oral mucositis. An open-label randomized controlled study. Two oncology hospitals in Ankara, Turkey. Patients receiving 5-fluorouracil-based chemotherapy regimens were divided into the intervention group (N=30) and control group (N=30). Basic oral care was prescribed to the control group, while the intervention group was prescribed sage tea-thyme-peppermint hydrosol in addition to basic oral care. All patients were called to assess their compliance with the study instructions on day 5 and 14. Oral mucositis was evaluated using an inspection method or by assessing oral cavity photos based on the World Health Organization oral toxicity scale on day 5 and 14. Most of the patients in the intervention group did not develop oral mucositis on day 5. In addition, the incidence of grade 1 oral mucositis was statistically lower in the intervention group (10%) than the control group (53.3%) on day 5. By day 14, the majority of patients in both the groups had grade 0 oral mucositis. Sage tea-thyme-peppermint hydrosol oral rinse has promising results in alleviating oral mucositis. This hydrosol can be recommended for clinical use as it is well tolerated and cost-effective. However, further randomized controlled trials are needed to support the study. Copyright © 2016 Elsevier Ltd. All rights reserved.

Determination of flow-rate characteristics and parameters of piezo pilot valves

Directory of Open Access Journals (Sweden)

Takosoglu Jakub

2017-01-01

Full Text Available Pneumatic directional valves are used in most industrial pneumatic systems. Most of them are two-stage valves controlled by a pilot valve. Pilot valves are often chosen randomly. Experimental studies in order to determine the flow-rate characteristics and parameters of pilot valves were not conducted. The paper presents experimental research of two piezo pilot valves.

Study Design for a Case Control Investigation of Cellular Telephones and Other Risk Factors for Brain Tumors in Adults

International Nuclear Information System (INIS)

Inskip, P.D.; Hatch, E.E.; Stewart, P.A.; Heineman, E.F.; Ziegler, R.G.; Dosemeci, M.; Parry, D.; Rothman, N.; Boice, J.D. Jr.; Wilcosky, T.C.; Watson, D.J.; Shapiro, W.R.; Selker, R.G.; Fine, H.A.; Black, P. McL.; Loeffler, J.S.; Linet, M.S.

1999-01-01

The aetiology of brain tumours is poorly understood. Due, in part, to public concern about a postulated relationship between the use of cellular telephones or other increasingly prevalent environmental exposures and the incidence of brain cancer in adults, the National Cancer Institute is collaborating with three US hospitals in a comprehensive case control study of malignant and benign brain tumours. Factors under consideration include use of cellular phones and other wireless communication devices, workplace exposures to chemical agents and electromagnetic fields, dietary factors, family history of tumours, genetic determinants of susceptibility, home appliance use, reproductive history and hormonal exposures, viruses, medical and dental exposure to ionising radiation, and other aspects of medical history. Approximately 800 newly diagnosed brain tumour cases and 800 controls were enrolled at hospitals in Boston, Phoenix and Pittsburgh from 1994 to 1998. Cases include all adults (age ≥ 18 y) newly diagnosed with a histologically confirmed intracranial glioma, histologically confirmed intracranial meningioma or acoustic neuroma. Controls are patients admitted to the same hospitals as the cases, and treated for any of a variety of non-malignant conditions. Key features of the study include its large size, the emphasis on rapid ascertainment of incident cases and interview of study subjects rather than surrogate respondents, the use of detailed, job-specific questions developed by industrial hygienists to ascertain occupational exposures, and the storage of blood samples for future evaluation of inherited susceptibility, biomarkers of exposure and gene environment interactions. (author)

A Pilot Study on the effects of Music Therapy on Frontotemporal Dementia - developing a research protocol

DEFF Research Database (Denmark)

Ridder, Hanne Mette Ochsner; Wigram, Tony; Ottesen, Anne Marie

2009-01-01

, and pharmacological treatment of the psychiatric symptoms is difficult, requiring specialist proficiency in the field. Pilot study: As there is not yet sufficient research that examines the effects of non-pharmacologic treatment with this group there is a need to develop valid and reliable research protocols....... As an example of a non-pharmacologic treatment procedure music therapy was investigated. With the focus to develop a research protocol for a future larger population study a pilot study was carried out. In two case studies a combination of data collection methods were examined with the overall goal to document...... changes in intersubjectivity. In this pilot testing there was a specific interest in selecting a relevant and manageable dementia specific instrument for measuring quality of life and relating it with other instruments. Following three instruments were tested: the Altzheimers Disease-Related Quality...

Investigation on the effects of pilot injection on low temperature combustion in high-speed diesel engine fueled with n-butanol–diesel blends

International Nuclear Information System (INIS)

Huang, Haozhong; Liu, Qingsheng; Yang, Ruzhi; Zhu, Tianru; Zhao, Ruiqing; Wang, Yaodong

2015-01-01

Highlights: • The effects of pre-injected timing and pre-injected mass were studied in CI engine. • The addition of n-butanol consumed OH free radicals, which delayed the ignition time. • With the increase of n-butanol, the BSFC and MPRR increased, NO_x and soot decreased. • With the advance of pilot injection timing, the BSFC increased, NO_x and soot decreased. • With the increase of pilot injection mass, NO_x increased, soot decreased then increased. - Abstract: The effect of pilot injection timing and pilot injection mass on combustion and emission characteristics under medium exhaust gas recirculation (EGR (25%)) condition were experimentally investigated in high-speed diesel engine. Diesel fuel (B0), two blends of butanol and diesel fuel denoted as B20 (20% butanol and 80% diesel in volume), and B30 (30% butanol and 70% diesel in volume) were tested. The results show that, for all fuels, when advancing the pilot injection timing, the peak value of heat release rate decreases for pre-injection fuel, but increases slightly for the main-injection fuel. Moreover, the in-cylinder pressure peak value reduces with the rise of maximum pressure rise rate (MPRR), while NO_x and soot emissions reduce. Increasing the pilot injection fuel mass, the peak value of heat release rate for pre-injected fuel increases, but for the main-injection, the peak descends, and the in-cylinder pressure peak value and NO_x emissions increase, while soot emission decreases at first and then increases. Blending n-butanol in diesel improves soot emissions. When pilot injection is adopted, the increase of n-butanol ratio causes the MPRR increasing and the crank angle location for 50% cumulative heat release (CA50) advancing, as well as NO_x and soot emissions decreasing. The simulation of the combustion of n-butanol–diesel fuel blends, which was based on the n-heptane–n-butanol–PAH–toluene mixing mechanism, demonstrated that the addition of n-butanol consumed OH free radicals

Cognitive-behavioural suicide prevention for male prisoners: a pilot randomized controlled trial.

Science.gov (United States)

Pratt, D; Tarrier, N; Dunn, G; Awenat, Y; Shaw, J; Ulph, F; Gooding, P

2015-12-01

Prisoners have an exceptional risk of suicide. Cognitive-behavioural therapy for suicidal behaviour has been shown to offer considerable potential, but has yet to be formally evaluated within prisons. This study investigated the feasibility of delivering and evaluating a novel, manualized cognitive-behavioural suicide prevention (CBSP) therapy for suicidal male prisoners. A pilot randomized controlled trial of CBSP in addition to treatment as usual (CBSP; n = 31) compared with treatment as usual (TAU; n = 31) alone was conducted in a male prison in England. The primary outcome was self-injurious behaviour occurring within the past 6 months. Secondary outcomes were dimensions of suicidal ideation, psychiatric symptomatology, personality dysfunction and psychological determinants of suicide, including depression and hopelessness. The trial was prospectively registered (number ISRCTN59909209). Relative to TAU, participants receiving CBSP therapy achieved a significantly greater reduction in suicidal behaviours with a moderate treatment effect [Cohen's d = -0.72, 95% confidence interval -1.71 to 0.09; baseline mean TAU: 1.39 (S.D. = 3.28) v. CBSP: 1.06 (S.D. = 2.10), 6 months mean TAU: 1.48 (S.D. = 3.23) v. CBSP: 0.58 (S.D. = 1.52)]. Significant improvements were achieved on measures of psychiatric symptomatology and personality dysfunction. Improvements on psychological determinants of suicide were non-significant. More than half of the participants in the CBSP group achieved a clinically significant recovery by the end of therapy, compared with a quarter of the TAU group. The delivery and evaluation of CBSP therapy within a prison is feasible. CBSP therapy offers significant promise in the prevention of prison suicide and an adequately powered randomized controlled trial is warranted.

ATC/pilot voice communications: A survey of the literature

Science.gov (United States)

Prinzo, O. Veronika; Britton, Thomas W.

1993-11-01

The first radio-equipped control tower in the United States opened at the Cleveland Municipal Airport in 1930. From that time to the present, voice radio communications have played a primary role in air safety. Verbal communications in air traffic control (ATC) operations have been frequently cited as causal factors in operational errors and pilot deviations in the FAA Operational Error and Deviation System, the NASA Aviation Safety Reporting System (ASRS), and reports derived from government sponsored research projects. Collectively, the data provided by these programs indicate that communications constitute a significant problem for pilots and controllers. Although the communications problem was well known the research literature was fragmented, making it difficult to appreciate the various types of verbal communications problems that existed and their unique influence on the quality of ATC/pilot communications. This is a survey of the voice radio communications literature. The 43 reports in the review represent survey data, field studies, laboratory studies, narrative reports, and reviews. The survey topics pertain to communications taxonomies, acoustical correlates and cognitive/psycholinguistic perspectives. Communications taxonomies were used to identify the frequency and types of information that constitute routine communications, as well as those communications involved in operational errors, pilot deviations, and other safety-related events. Acoustical correlate methodologies identified some qualities of a speaker's voice, such as loudness, pitch, and speech rate, which might be used potentially to monitor stress, mental workload, and other forms of psychological or physiological factors that affect performance. Cognitive/psycho-linguistic research offered an information processing perspective for understanding how pilots' and controllers' memory and language comprehension processes affect their ability to communicate effectively with one another. This

The Association Between Urban Tree Cover and Gun Assault: A Case-Control and Case-Crossover Study.

Science.gov (United States)

Kondo, Michelle C; South, Eugenia C; Branas, Charles C; Richmond, Therese S; Wiebe, Douglas J

2017-08-01

Green space and vegetation may play a protective role against urban violence. We investigated whether being near urban tree cover during outdoor activities was related to being assaulted with a gun. We conducted geographic information systems-assisted interviews with boys and men aged 10-24 years in Philadelphia, Pennsylvania, including 135 patients who had been shot with a firearm and 274 community controls, during 2008-2011. Each subject reported a step-by-step mapped account of where and with whom they traveled over a full day from waking until being assaulted or going to bed. Geocoded path points were overlaid on mapped layers representing tree locations and place-specific characteristics. Conditional logistic regressions were used to compare case subjects versus controls (case-control) and case subjects at the time of injury versus times earlier that day (case-crossover). When comparing cases at the time of assault to controls matched at the same time of day, being under tree cover was inversely associated with gunshot assault (odds ratio (OR) = 0.70, 95% confidence interval (CI): 0.55, 0.88), especially in low-income areas (OR = 0.69, 95% CI: 0.54, 0.87). Case-crossover models confirmed this inverse association overall (OR = 0.55, 95% CI: 0.34, 0.89) and in low-income areas (OR = 0.54, 95% CI: 0.33, 0.88). Urban greening and tree cover may hold promise as proactive strategies to decrease urban violence. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Exposure to pistachio pesticides and stillbirth: a case-control study.

Science.gov (United States)

Razi, Saeid; Rezaeian, Mohsen; Dehkordi, Fatemeh Ghani; Manshoori, Azita; Goujani, Reza; Vazirinejad, Reza

2016-01-01

Stillbirth is an undesirable outcome of pregnancy. In light of the increasing use of pesticides and growing concerns about the possible health effects of agricultural pesticides, we investigated the effect of exposure to pistachio pesticides on stillbirth in pregnant mothers. This case-control study was conducted in Rafsanjan, Iran from 2011 to 2012. A total of 125 females who had a recent stillbirth were included as the case group, and 250 controls were selected from females who had a recent live birth. For each case, two controls with the nearest propensity score to the case were selected. Data were collected using a protocol developed by the researcher that involved interviewing respondents and reviewing their medical records. Conditional multivariate and univariate logistic regression analysis were performed and odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. The ORs of stillbirth in mothers living in pistachio gardens and those who were exposed to sprayed pesticides, in comparison to the controls, were 14.1 (95% CI, 3.3 to 63.4) and 5.0 (95% CI, 1.2 to 28.6), respectively. No significant differences were found in stillbirth rates according to the distance between the mother's residence and a pistachio garden or involvement in agricultural activities. The results of our study showed that exposure to pistachio pesticides during pregnancy may increase the likelihood of stillbirth in mothers.

Longitudinal Absolute Stability of a BWB Aircraft-Pilot System with Saturated Actuator Model

Directory of Open Access Journals (Sweden)

Claudia Alice STATE

2013-09-01

Full Text Available This paper deals with the analysis of the P(ilot I(n-the-Loop O(scillations of the second category (with rate and position liming in the closed loop pilot-vehicle system, caused by the dynamic coupling between the human pilot and the aircraft. The analysis is made in the context of the longitudinal motion and the theoretical model of the airplane presented in this article is a (Blended(Wing (Body tailless configuration. In what concerns the human operator, this is expressed by the Synchronous Pilot Model, which is represented by a simple gain, without a specific delay. The Routh-Hurwitz criterion is used in order to analyze the longitudinal stability of the low-order pilot-airplane system without the influence of actuator nonlinearity (this means that the unsaturated actuator model is employed for the mentioned algebraic criterion. Most emphasis is put on the frequency Popov criterion, which is used to investigate the absolute stability property of the short-period model in the presence of the actuator rate saturation, in the condition of the Lurie problem. The transfer function of the longitudinal BWB model, obtained from open-loop analysis, has a double pole at the origin and, for the absolute stability feedback structure that contains the nonlinearity of the saturation type, the Popov frequency-domain inequalities are applied to the PIO II problem in this critical case.

A pilot modeling technique for handling-qualities research

Science.gov (United States)

Hess, R. A.

1980-01-01

A brief survey of the more dominant analysis techniques used in closed-loop handling-qualities research is presented. These techniques are shown to rely on so-called classical and modern analytical models of the human pilot which have their foundation in the analysis and design principles of feedback control. The optimal control model of the human pilot is discussed in some detail and a novel approach to the a priori selection of pertinent model parameters is discussed. Frequency domain and tracking performance data from 10 pilot-in-the-loop simulation experiments involving 3 different tasks are used to demonstrate the parameter selection technique. Finally, the utility of this modeling approach in handling-qualities research is discussed.

Advanced piloted aircraft flight control system design methodology. Volume 1: Knowledge base

Science.gov (United States)

Mcruer, Duane T.; Myers, Thomas T.

1988-01-01

The development of a comprehensive and electric methodology for conceptual and preliminary design of flight control systems is presented and illustrated. The methodology is focused on the design stages starting with the layout of system requirements and ending when some viable competing system architectures (feedback control structures) are defined. The approach is centered on the human pilot and the aircraft as both the sources of, and the keys to the solution of, many flight control problems. The methodology relies heavily on computational procedures which are highly interactive with the design engineer. To maximize effectiveness, these techniques, as selected and modified to be used together in the methodology, form a cadre of computational tools specifically tailored for integrated flight control system preliminary design purposes. While theory and associated computational means are an important aspect of the design methodology, the lore, knowledge and experience elements, which guide and govern applications are critical features. This material is presented as summary tables, outlines, recipes, empirical data, lists, etc., which encapsulate a great deal of expert knowledge. Much of this is presented in topical knowledge summaries which are attached as Supplements. The composite of the supplements and the main body elements constitutes a first cut at a a Mark 1 Knowledge Base for manned-aircraft flight control.

Patent foramen ovale and asymptomatic brain lesions in military fighter pilots.

Science.gov (United States)

Kang, Kyung Wook; Kim, Joon-Tae; Choi, Won-Ho; Park, Won-Ju; Shin, Young Ho; Choi, Kang-Ho

2014-10-01

Previous studies have reported higher incidence of white matter lesions (WMLs) in military pilots. The anti-gravity straining maneuver, which fighter military pilots perform numerously during a flight is identical to the valsalva maneuver. We sought to investigate the prevalence of right-to-left shunt (RLS) associated with WMLs in military pilots. A prospective study was performed involving military pilots who visited the Airomedical Center. The pilots underwent brain magnetic resonance imaging (MRI) scan and transcranial Doppler (TCD) with intravenous injection of agitated saline solution for the detection of RLS. Periventricular WMLs (PVWMLs) on MRI were graded using Fazeka's scale, and deep WMLs (DWMLs) were graded using Scheltens's scale. This study included 81 military pilots. RLS on TCD was observed less frequently in non-fighter pilots than in fighter pilots (35.5% vs. 64.5%, p=0.011). Fighter pilot was an independently associated factor with RLS on the TCD. DWMLs were independently associated with RLSs through a patent foramen ovale (PFO) (OR 3.507, 95% CI 1.223-10.055, p=0.02). The results suggest that DWMLs in military pilots may significantly be associated with RLS via PFO. Additional investigations are warranted. Copyright © 2014 Elsevier B.V. All rights reserved.

Use of oral cholera vaccines in an outbreak in Vietnam: a case control study.

Directory of Open Access Journals (Sweden)

Dang Duc Anh

Full Text Available BACKGROUND: Killed oral cholera vaccines (OCVs are available but not used routinely for cholera control except in Vietnam, which produces its own vaccine. In 2007-2008, unprecedented cholera outbreaks occurred in the capital, Hanoi, prompting immunization in two districts. In an outbreak investigation, we assessed the effectiveness of killed OCV use after a cholera outbreak began. METHODOLOGY/PRINCIPAL FINDINGS: From 16 to 28 January 2008, vaccination campaigns with the Vietnamese killed OCV were held in two districts of Hanoi. No cholera cases were detected from 5 February to 4 March 2008, after which cases were again identified. Beginning 8 April 2008, residents of four districts of Hanoi admitted to one of five hospitals for acute diarrhea with onset after 5 March 2008 were recruited for a matched, hospital-based, case-control outbreak investigation. Cases were matched by hospital, admission date, district, gender, and age to controls admitted for non-diarrheal conditions. Subjects from the two vaccinated districts were evaluated to determine vaccine effectiveness. 54 case-control pairs from the vaccinated districts were included in the analysis. There were 8 (15% and 16 (30% vaccine recipients among cases and controls, respectively. The vaccine was 76% protective against cholera in this setting (95% CI 5% to 94%, P = 0.042 after adjusting for intake of dog meat or raw vegetables and not drinking boiled or bottled water most of the time. CONCLUSIONS/SIGNIFICANCE: This is the first study to explore the effectiveness of the reactive use of killed OCVs during a cholera outbreak. Our findings suggest that killed OCVs may have a role in controlling cholera outbreaks.

Alcohol interventions for mandated students: behavioral outcomes from a randomized controlled pilot study.

Science.gov (United States)

Logan, Diane E; Kilmer, Jason R; King, Kevin M; Larimer, Mary E

2015-01-01

This study investigated the effectiveness of three single-session interventions with high-risk mandated students while considering the influence of motivational interviewing (MI) microskills. This randomized, controlled pilot trial evaluated single-session interventions: Alcohol Skills Training Program (ASTP), Brief Alcohol Screening and Intervention for College Students (BASICS) feedback sessions, and treatment-as-usual Alcohol Diversion Program (ADP) educational groups. Participants were 61 full-time undergraduates at a southern U.S. campus sanctioned to a clinical program following violation of an on-campus alcohol policy (Mage = 19.16 years; 42.6% female). RESULTS revealed a significant effect of time for reductions in estimated blood alcohol concentration (eBAC) and number of weekly drinks but not in alcohol-related consequences. Although ASTP and BASICS participants reported significant decreases in eBAC over time, ADP participant levels did not change (with no intervention effects on quantity or consequences). MI microskills were not related to outcomes. RESULTS from this study suggest equivalent behavioral impacts for the MI-based interventions, although individual differences in outcome trajectories suggest that research is needed to further customize mandated interventions. Given the overall decrease in eBAC following the sanction, the lack of reduction in the ADP condition warrants caution when using education-only interventions.

Competence feedback improves CBT competence in trainee therapists: A randomized controlled pilot study.

Science.gov (United States)

Weck, Florian; Kaufmann, Yvonne M; Höfling, Volkmar

2017-07-01

The development and improvement of therapeutic competencies are central aims in psychotherapy training; however, little is known about which training interventions are suitable for the improvement of competencies. In the current pilot study, the efficacy of feedback regarding therapeutic competencies was investigated in cognitive behavioural therapy (CBT). Totally 19 trainee therapists and 19 patients were allocated randomly to a competence feedback group (CFG) or control group (CG). Two experienced clinicians and feedback providers who were blind to the treatment conditions independently evaluated therapeutic competencies on the Cognitive Therapy Scale at five treatment times (i.e., at Sessions 1, 5, 9, 13, and 17). Whereas CFG and CG included regular supervision, only therapists in the CFG additionally received written qualitative and quantitative feedback regarding their demonstrated competencies in conducting CBT during treatment. We found a significant Time × Group interaction effect (η² = .09), which indicates a larger competence increase in the CFG in comparison to the CG. Competence feedback was demonstrated to be suitable for the improvement of therapeutic competencies in CBT. These findings may have important implications for psychotherapy training, clinical practice, and psychotherapy research. However, further research is necessary to ensure the replicability and generalizability of the findings.

Pilot-Scale Laboratory Instruction for Chemical Engineering: The Specific Case of the Pilot-Unit Leading Group

Science.gov (United States)

Billet, Anne-Marie; Camy, Severine; Coufort-Saudejaud, Carole

2010-01-01

This paper presents an original approach for Chemical Engineering laboratory teaching that is currently applied at INP-ENSIACET (France). This approach, referred to as "pilot-unit leading group" is based on a partial management of the laboratories by the students themselves who become temporarily in charge of one specific laboratory. In…

Accuracy of preemptively constructed, Cone Beam CT-, and CAD/CAM technology-based, individual Root Analogue Implant technique: an in vitro pilot investigation

NARCIS (Netherlands)

Moin, D.A.; Hassan, B.; Parsa, A.; Mercelis, P.; Wismeijer, D.

2014-01-01

Objectives The aim of this in vitro pilot investigation is to assess the accuracy of the preemptive individually fabricated root analogue implant (RAI) based on three-dimensional (3D) root surface models obtained from a cone beam computed tomography (CBCT) scan, computer-aided designing (CAD), and

Childhood leukaemia in relation to radiofrequency electromagnetic fields emitted from television and radio broadcast transmitters: epidemiological aspects of a case-control study in Germany; Leukaemie bei Kindern in der Umgebung von Sendestationen des Rundfunks. Anforderungen an das Studiendesign

Energy Technology Data Exchange (ETDEWEB)

Merzenich, H.; Bennack, S.; Blettner, M. [Mainz Univ. (DE). Inst. fuer Medizinische Biometrie, Epidemiologie und Informatik (IMBEI); Schmiedel, S.; Schuez, J. [Mainz Univ. (DE). Inst. fuer Medizinische Biometrie, Epidemiologie und Informatik (IMBEI); Danish Cancer Society, Copenhagen (Denmark). Inst. of Cancer Epidemiology; Brueggemeyer, H. [Niedersaechsischer Landesbetrieb fuer Wasserwirtschaft, Kuesten- und Naturschutz, AB35 - Strahlenschutz in Niedersachsen, Hannover (Germany); Philipp, J. [Suedwestrundfunk, Stuttgart (Germany). Abt. Frequenz- und Versorgungsplanung; Spix, C. [Mainz Univ. (Germany). Deutsches Kinderkrebsregister

2007-07-01

Leukaemia is the most common type of cancer in children accounting for about a third of all cancers in children under the age of 15 years. Environmental factors such as non-ionising radiation exposure might play a role in the aetiology of childhood leukaemia. However, data to support such hypotheses are inconsistent. A case control study has been set up in West Germany (University of Mainz) in order to determine whether there is an increased risk of childhood leukaemia in populations exposed to radiofrequency electromagnetic fields from TV and/or Radio towers. Cases are children aged 0 to 14 years with a primary leukaemia diagnosed between 1984 and 2003 who lived in the vicinity of these TV- and/ or Radio towers. Cases have been identified through the German Childhood Cancer Registry. Three controls per case have been individually matched by age at diagnosis, sex, time of diagnosis and study area. The study focuses on an individual retrospective exposure assessment using data from transmitter network operators. The study has started in March 2005 with a pilot investigation in order to specify the study design and the methods for exposure assessment. A total of 2009 eligible cases have been identified. The study will be finished end of 2007. (orig.)

A Note on Penalized Regression Spline Estimation in the Secondary Analysis of Case-Control Data

KAUST Repository

Gazioglu, Suzan

2013-05-25

Primary analysis of case-control studies focuses on the relationship between disease (D) and a set of covariates of interest (Y, X). A secondary application of the case-control study, often invoked in modern genetic epidemiologic association studies, is to investigate the interrelationship between the covariates themselves. The task is complicated due to the case-control sampling, and to avoid the biased sampling that arises from the design, it is typical to use the control data only. In this paper, we develop penalized regression spline methodology that uses all the data, and improves precision of estimation compared to using only the controls. A simulation study and an empirical example are used to illustrate the methodology.

A Note on Penalized Regression Spline Estimation in the Secondary Analysis of Case-Control Data

KAUST Repository

Gazioglu, Suzan; Wei, Jiawei; Jennings, Elizabeth M.; Carroll, Raymond J.

2013-01-01

Primary analysis of case-control studies focuses on the relationship between disease (D) and a set of covariates of interest (Y, X). A secondary application of the case-control study, often invoked in modern genetic epidemiologic association studies, is to investigate the interrelationship between the covariates themselves. The task is complicated due to the case-control sampling, and to avoid the biased sampling that arises from the design, it is typical to use the control data only. In this paper, we develop penalized regression spline methodology that uses all the data, and improves precision of estimation compared to using only the controls. A simulation study and an empirical example are used to illustrate the methodology.

External radiotherapy prior to thyroid cancer: A case-control study

International Nuclear Information System (INIS)

Hallquist, A.; Loefroth, P.O.; Hardell, L.

1993-01-01

The aim of this investigation was to study previous radiotherapy of malignant diseases as a risk factor for thyroid cancer. By using the Swedish Cancer Registry all cases of thyroid cancer with another malignant disease at least one year previously and living within the catchment area of the hospital were traced. During 1959-1989 a total of 1056 cases of thyroid cancer were identified. Of these, 37 had had another previous malignant disease and they constituted the cases in this study. As controls four persons with at least two malignant diseases, thyroid cancer excluded, were selected for each case from the same cancer registry. Ten (27.0%) of the 37 patients with thyroid cancer as a second tumor had earlier been irradiated with the treatment dose including the thyroid gland as compared with 34 (24.5%) of the 139 control patients. Eight of the ten cases with previous irradiation of the thyroid gland had papillary cancer. The median latency was 13 years. The estimated radiation dose in the thyroid varied between 3 and 40 Gy. External radiotherapy gave a crude odds ratio of 1.1 with 95% confidence interval = 0.5-2.8 for thyroid cancer. The weighted odds ratio was calculated to 2.3 with confidence interval = 0.5-8.9. This case-control study gave a nonsignificantly increased odds ratio for thyroid cancer in patients with external radiotherapy including the thyroid gland. 26 refs., 4 tabs

75 FR 56857 - Pilot, Flight Instructor, and Pilot School Certification

Science.gov (United States)

2010-09-17

...-2006-26661; Amendment No., 141-14] RIN 2120-AI86 Pilot, Flight Instructor, and Pilot School..., certification, and operating requirements for pilots, flight instructors, ground instructors, and pilot schools...: Background On August 21, 2009, the FAA published the ``Pilot, Flight Instructor, and Pilot School...

Effects of sculpture based art therapy in dementia patients-A pilot study.

Science.gov (United States)

Seifert, Kathrin; Spottke, Annika; Fliessbach, Klaus

2017-11-01

Art and art therapy open up interesting possibilities for dementia patients. However, it has not been evaluated scientifically so far, whether the art of sculpting has any benefits. In this non-randomized pilot study with twelve participants, we investigated the feasibility and acceptance of sculptural activity in patients with dementia and the effects on their well-being. A questionnaire was custom-designed to investigate five key aspects of well-being: mental state and concentration, corporeal memory, self-reliance, self-esteem and physicality. Remarkable improvements were seen in several subscales in the sculptural activity group, but not the control group: Mental state and concentration (nine of thirteen key aspects), self-reliance (four of five), self-esteem (one of one) and physicality (two of two). The results of this pilot study indicate the multidimensional effects of sculptural activity on patients living with dementia. The field would benefit greatly from further research.

Maternal note-taking and infant care: a pilot randomised controlled trial.

Science.gov (United States)

Kistin, Caroline J; Barrero-Castillero, Alejandra; Lewis, Sheilajane; Hoch, Rachel; Philipp, Barbara L; Bauchner, Howard; Wang, C Jason

2012-10-01

A pilot randomised controlled trial was conducted with postpartum mothers to assess the feasibility and impact of note-taking during newborn teaching. Controls received standard teaching; the intervention group received pen and paper to take notes. Subjects were called 2 days post-discharge to assess infant sleep position, breastfeeding, car seat use, satisfaction and information recall. 126 mothers were randomised. There was a consistent trend that intervention subjects were more likely to report infant supine sleep position (88% vs 78%, relative risks (RR) 1.13; 95% CI 0.95 to 1.34), breastfeeding (96% vs 86%, RR 1.11; 95% CI 0.99 to 1.25) and correct car seat use (98% vs 87%, RR 1.12; 95% CI 1.00 to 1.25). Satisfaction and information recall did not differ. Among first-time mothers, intervention subjects were significantly more likely to report infant supine sleep position (95% vs 65%, RR 1.46; 95% CI 1.06 to 2.00). Maternal note-taking is feasible and potentially efficacious in promoting desirable infant care.

Low maternal folate concentrations and maternal MTHFR C677T polymorphism are associated with an increased risk for neural tube defects in offspring: a case-control study among Pakistani case and control mothers.

Science.gov (United States)

Nauman, Nuzhat; Jalali, Samina; Shami, Sajjad; Rafiq, Shireen; Große, Greta; Hilger, Alina C; Zhang, Rhong; Mansoor, Saira; Ludwig, Michael; Reutter, Heiko

2018-01-01

There is considerable evidence that periconceptional maternal folate deficiency and coding variants in maternal genes coding for critical enzymes in the folate pathway are associated with neural tube defects (NTDs) in offspring. In a case-control study we investigated C677T polymorphism in the 5,10- methylenetetrahydrofolate reductase (MTHFR) gene in case and control mothers of Pakistani origin, and compared these with the respective maternal folate concentrations measured at the time of delivery. A case-control study was conducted among 109 case and 100 control mothers identified through the Holy Family Hospital Rawalpindi, Quaid-i-Azam University, Islamabad, Pakistan. Red blood cell (RBC) and serum folate concentrations and MTHFRC677T polymorphism were compared between case and control mothers. Mean RBC folate and serum folate concentrations were significantly lower in cases compared with control mothers (pcases compared with control mothers (CC vs TT pcases compared with control mothers (C vs T pCase mothers with 677CT or 677TT genotypes had significantly lower serum (pstudy provides further evidence that maternal folate deficiency and MTHFRC677T polymorphism might be associated with an increased risk for NTDs in offspring. Our results are limited by the fact that maternal folate concentrations were not obtained during the periconceptional period, but at delivery. Further analyses, including maternal folate levels during the periconceptional period, are warranted.

Electrocoagulation project: Pilot study testwork

Energy Technology Data Exchange (ETDEWEB)

Donini, J.C.; Garand, D.K.; Hassan, T.A.; Kar, K.L.; Thind, S.S.

1991-09-01

When a suspension or emulsion flows between two sacrificial metal electrodes excited by ac, the dispersed phase is consolidated and then settles. Laboratory-scale investigation of this mechanism, called electrocoagulation, and of its areas of application to water treatment were previously completed and a subsequent project was initiated to design and construct pilot-scale equipment consisting of an electrocoagulation cell, power supply, and computerized control system. The constructed pilot plant was used to test the effectiveness of electrocoagulation to clarify coal processing plant effluent. Results obtained with clay suspensions showed that flow conditions in the cell have a major effect on electric power consumption, and a reduction by a factor of three on this crucial cost parameter appeared possible compared to a previously tested batch-scale electrocoagulation system. Results obtained using the coal plant thickener feed closely duplicated those obtained with the clay mixtures. Aluminum electrode consumption, however, remained unchanged compared to the bench-scale tests. Supernatant clarity far exceeded requirements, while settling rate was too low. The settling could be speeded up by appropriate use of chemicals, but such addition affects the coagulation mechanism and reduces supernatant clarity. A tradeoff between settling rate and clarity was thus established. The total cost of treatment was deemed to be in excess of coal company requirements, but the pilot tests revealed much about the electrocoagulation system under continuous flow conditions. The technology is seen as having application in other areas such as municipal and industrial waste treatment. 22 refs., 6 figs., 2 tabs.

Effect of alpha amylase on early childhood caries: a matched case-control study

OpenAIRE

Mojarad, Farzad; Department of Pediatric Dentistry, School of Dentistry, Hamadan University of Medical Sciences, Hamadan; Fazlollahifar, Samira; Department of Pediatric Dentistry, School of Dentistry, Hamadan University of Medical Sciences, Hamadan; Poorolajal, Jalal; Research Center for Health Sciences, Department of Epidemiology & Biostatistics, School of Public Health, Hamadan University of Medical Sciences, Hamadan; Hajilooi, Mehrdad; Department of Pathology, School of Dentistry, Hamadan University of Medical Sciences, Hamadan

2013-01-01

Objectives: There are a few studies addressing the relationship between salivary alpha-amylase and dental caries. This study was implemented in order to investigate the effect of salivary alpha-amylase level on early childhood caries (ECC).Materials and Methods: In this matched case-control study, which was carried out from November 2011 to March 2012 in Hamadan City, the west of Iran, mean levels of salivary alpha-amylase of 84 ECC-active cases were compared to that of 84 ECC-free controls u...

Investigation of Energy-Efficient Supermarket Display Cases

Energy Technology Data Exchange (ETDEWEB)

Walker, D.H.

2005-01-21

contributing about 3/4 of that fraction. Consequently, the focus of this investigation has tilted toward the open, vertical, multi-deck medium temperature case type. Various technologies and control methods are energy efficiency measures (EEMs) that could be applied to display cases and result in the reduction of the refrigeration load and of the energy consumption of the supermarket refrigeration system. An extensive evaluation of the EEMs was conducted in order to select those that met the following criteria: (1) Near-term implementation--All EEMs considered could be implemented with existing refrigeration hardware and technology. (2) Potential for energy-efficiency improvements--Energy savings and/or refrigeration load reduction must be obtained by the implementation of the EEM. (3) Enhancement of the ability to maintain target product temperature--Proper operation of the display case and maintenance of the stored product temperature could not be compromised by the use of the EEM. The energy impact of a number of viable display case EEMs was quantified by performing whole building hourly simulations. A special version of the U.S. Department of Energy's (DOE-2.3) program was used to develop a model of a supermarket. The model was then calibrated using available end-use monitored data to increase confidence in simulation results.

Risk factors for Buruli ulcer in Côte d'Ivoire: Results of a case-control ...

African Journals Online (AJOL)

A case-control study was carried out in 3 highly endemic regions of Côte d'Ivoire to study risk factors for Buruli ulcer. A case was defined as a Buruli ulcer occurring less than one year before the date of survey, resident in one of the regions investigated and there was no history of Buruli ulcer illness. Controls were selected ...

User Participation in Pilot Implementation: Porters and Nurses Coordinating Patient Transports

DEFF Research Database (Denmark)

Torkilsheyggi, Arnvør Martinsdóttir á; Hertzum, Morten

2014-01-01

Pilot implementations provide users with real-work experiences of how a system will affect their daily work before the design of the system is finalized. On the basis of a pilot implementation of a system for coordinating the transport of patients by hospital porters, we investigate pilot impleme...... the use of the pilot system because the porters and nurses learned about their needs throughout the pilot implementation, not just during use. Finally, we discuss how the scope and duration of a pilot implementation influence the conditions for participation....