Timeline Analysis Program (TLA-1)
NASA Technical Reports Server (NTRS)
Miller, K. H.
1976-01-01
The Timeline Analysis Program (TLA-1) was described. This program is a crew workload analysis computer program that was developed and expanded from previous workload analysis programs, and is designed to be used on the NASA terminal controlled vehicle program. The following information is described: derivation of the input data, processing of the data, and form of the output data. Eight scenarios that were created, programmed, and analyzed as verification of this model were also described.
NASA TLA workload analysis support. Volume 3: FFD autopilot scenario validation data
NASA Technical Reports Server (NTRS)
Sundstrom, J. L.
1980-01-01
The data used to validate a seven time line analysis of forward flight deck autopilot mode for the pilot and copilot for NASA B737 terminal configured vehicle are presented. Demand workloads are given in two forms: workload histograms and workload summaries (bar graphs). A report showing task length and task interaction is also presented.
NASA Technical Reports Server (NTRS)
Sundstrom, J. L.
1980-01-01
The techniques required to produce and validate six detailed task timeline scenarios for crew workload studies are described. Specific emphasis is given to: general aviation single pilot instrument flight rules operations in a high density traffic area; fixed path metering and spacing operations; and comparative workload operation between the forward and aft-flight decks of the NASA terminal control vehicle. The validation efforts also provide a cursory examination of the resultant demand workload based on the operating procedures depicted in the detailed task scenarios.
NASA TLA workload analysis support. Volume 2: Metering and spacing studies validation data
NASA Technical Reports Server (NTRS)
Sundstrom, J. L.
1980-01-01
Four sets of graphic reports--one for each of the metering and spacing scenarios--are presented. The complete data file from which the reports were generated is also given. The data was used to validate the detail task of both the pilot and copilot for four metering and spacing scenarios. The output presents two measures of demand workload and a report showing task length and task interaction.
Evaluation of the impact of a total automation system in a large core laboratory on turnaround time.
Lou, Amy H; Elnenaei, Manal O; Sadek, Irene; Thompson, Shauna; Crocker, Bryan D; Nassar, Bassam
2016-11-01
Growing financial and workload pressures on laboratories coupled with user demands for faster turnaround time (TAT) has steered the implementation of total laboratory automation (TLA). The current study evaluates the impact of a complex TLA on core laboratory efficiency through the analysis of the In-lab to Report TAT (IR-TAT) for five representative tests based on the different requested priorities. Mean, median and outlier percentages (OP) for IR-TAT were determined following TLA implementation and where possible, compared to the pre-TLA era. The shortest mean IR-TAT via the priority lanes of the TLA was 22min for Complete Blood Count (CBC), followed by 34min, 39min and 40min for Prothrombin time (PT), urea and potassium testing respectively. The mean IR-TAT for STAT CBC loaded directly on to the analyzers was 5min shorter than that processed via the TLA. The mean IR-TATs for both STAT potassium and urea via offline centrifugation were comparable to that processed by the TLA. The longest mean IR-TAT via regular lanes of the TLA was 62min for Thyroid-Stimulating Hormone (TSH) while the shortest was 17min for CBC. All parameters for IR-TAT for CBC and PT tests decreased significantly post- TLA across all requested priorities in particular the outlier percentage (OP) at 30 and 60min. TLA helps to efficiently manage substantial volumes of samples across all requested priorities. Manual processing for small STAT volumes, at both the initial centrifugation stage and front loading directly on to analyzers, is however likely to yield the shortest IR-TAT. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.
Streitberg, George S; Angel, Lyndall; Sikaris, Kenneth A; Bwititi, Phillip T
2012-10-01
Pathology has developed substantially since the 1990s with the introduction of total laboratory automation (TLA), in response to workloads and the need to improve quality. TLA has enhanced core laboratories, which evolved from discipline-based laboratories. Work practices have changed, with central reception now loading samples onto the Inlet module of the TLA. It is important to continually appraise technology. This study looked at the impact of technology using a self-administered survey to seniors in clinical biochemistry in NATA GX/GY-classified laboratories in Australia. The responses were yes, no, or not applicable and are expressed as percentages of responses. Some of the questions sourced for descriptive answers. Eighty-one laboratories responded, and the locations were 63%, 33%, and 4% in capital cities, regional cities, and country towns, respectively. Forty-two percent were public and 58% private. Clinical biochemistry was in all core laboratories of various sizes, and most performed up to 20 tests per sample. Thirty percent of the 121 surveyed laboratories had plans to install an automated line. Fifty-eight percent had hematology and biochemistry instrumentations in their peripheral laboratory, and 16% had a STAT laboratory on the same site as the core laboratory. There were varied instruments in specialist laboratories, and analyzers with embedded computers were in all laboratories. Medium and large laboratories had workstations with integrated instruments, and some large laboratories had TLA. Technology evolution and rising demand for pathology services make it imperative for laboratories to embrace such changes and reorganize the laboratories to take into account point-of-care testing and the efficiencies of core laboratories and TLA.
Casis, E; Garrido, A; Uranga, B; Vives, A; Zufiaurre, C
2001-01-01
Total laboratory automation (TLA) can be substituted in mid-size laboratories by a computer sample workflow control (virtual automation). Such a solution has been implemented in our laboratory using PSM, software developed in cooperation with Roche Diagnostics (Barcelona, Spain), to this purpose. This software is connected to the online analyzers and to the laboratory information system and is able to control and direct the samples working as an intermediate station. The only difference with TLA is the replacement of transport belts by personnel of the laboratory. The implementation of this virtual automation system has allowed us the achievement of the main advantages of TLA: workload increase (64%) with reduction in the cost per test (43%), significant reduction in the number of biochemistry primary tubes (from 8 to 2), less aliquoting (from 600 to 100 samples/day), automation of functional testing, drastic reduction of preanalytical errors (from 11.7 to 0.4% of the tubes) and better total response time for both inpatients (from up to 48 hours to up to 4 hours) and outpatients (from up to 10 days to up to 48 hours). As an additional advantage, virtual automation could be implemented without hardware investment and significant headcount reduction (15% in our lab).
1985-01-01
We have determined the DNA sequence of a gene encoding a thymus leukemia (TL) antigen in the BALB/c mouse, and have more definitively mapped the cloned BALB/c Tla-region class I gene clusters. Analysis of the sequence shows that the Tla gene is less closely related to the H-2 genes than H-2 genes are to one another or to a Qa-2,3-region genes. The Tla gene, 17.3A, contains an apparent gene conversion. Comparison of the BALB/c Tla genes with those from C57BL shows that BALB/c has more Tla-region class I genes, and that one of the genes absent in C57BL is gene 17.3A. PMID:3894562
Mosshammer, Dirk; Mayer, Benjamin; Joos, Stefanie
2013-06-01
Therapeutic injections with local anesthetics (TLA) are widespread and are used for various symptoms of the musculoskeletal system. The aim of the present project was to evaluate the efficacy and safety of TLA in the treatment of musculoskeletal disorders. Systematic literature search for controlled clinical trials (Medline, Cochrane, CAMbase, hand search of references) without language limitation; independent screening of the search results (n=3200 hits), abstract reading, and full-text analysis by 2 reviewers. Two authors independently extracted the data and assessed study quality. Meta-analysis was calculated for studies using a continuous scale for pain assessment. Twenty-four controlled trials were included in this review. In almost all studies no primary outcome measure was defined and the overall study quality was low. The qualitative data analysis revealed no clear trend for or against TLA. The meta-analysis of 12 studies showed no significant difference in pain reduction for TLA compared with control treatments consisting of saline injections or other substances, oral analgesics, or nonpharmacological interventions (standardized mean difference -0.31, 95% confidence interval, -0.75 to 0.14). Minor adverse side effects were reported in 7 studies in both the TLA and the control groups with no trend for one of the groups to be safer. Despite the widespread use of TLA for musculoskeletal disorders in daily practice, available data are sparse and of low quality and, therefore, do not allow a final recommendation. High-quality studies are needed to close the gap between common practice and research.
Theparee, Talent; Das, Sanchita; Thomson, Richard B
2018-01-01
Technological advances have changed the practice of clinical microbiology. We implemented Bruker matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and BD Kiestra total laboratory automation (TLA) 4 and 3 years ago, respectively. To assess the impact of these new technologies, we compared turnaround times (TATs) for positive and negative urine cultures before and after implementation. In comparison I, TATs for 61,157 urine cultures were extracted for two periods corresponding to pre-TLA and post-TLA, both using MALDI-TOF MS for organism identification. In comparison II, time to organism identification (ID) and antimicrobial susceptibility (AST) reports were calculated for 5,402 positive culture reports representing four different periods: (i) manual plating and conventional biochemical identification (CONV), (ii) manual plating and MALDI-TOF MS identification (MALDI), (iii) MALDI-TOF MS identification and early phase implementation of TLA (TLA1), and (iv) MALDI-TOF MS identification and late phase implementation of TLA (TLA2). By the comparison I results, median pre- and post-TLA TATs to organism IDs (18.5 to 16.9 h), AST results (41.8 to 40.8 h), and preliminary results for negative cultures (17.7 to 13.6 h), including interquartile ranges for all comparisons, were significantly decreased post-TLA ( P < 0.001). By the comparison II results, MALDI significantly improved TAT to organism ID compared to CONV (21.3 to 18 h). TLA further improved overall TAT to ID (18 to 16.5 h) and AST (42.3 to 40.7 h) results compared to MALDI ( P < 0.001). In summary, TLA significantly improved TAT to organism ID, AST report, and preliminary negative results. MALDI-TOF MS significantly improved TAT for organism ID. Use of MALDI-TOF MS and TLA individually and together results in significant decreases in microbiology report TATs. Copyright © 2017 Theparee et al.
Theparee, Talent; Das, Sanchita
2017-01-01
ABSTRACT Technological advances have changed the practice of clinical microbiology. We implemented Bruker matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) and BD Kiestra total laboratory automation (TLA) 4 and 3 years ago, respectively. To assess the impact of these new technologies, we compared turnaround times (TATs) for positive and negative urine cultures before and after implementation. In comparison I, TATs for 61,157 urine cultures were extracted for two periods corresponding to pre-TLA and post-TLA, both using MALDI-TOF MS for organism identification. In comparison II, time to organism identification (ID) and antimicrobial susceptibility (AST) reports were calculated for 5,402 positive culture reports representing four different periods: (i) manual plating and conventional biochemical identification (CONV), (ii) manual plating and MALDI-TOF MS identification (MALDI), (iii) MALDI-TOF MS identification and early phase implementation of TLA (TLA1), and (iv) MALDI-TOF MS identification and late phase implementation of TLA (TLA2). By the comparison I results, median pre- and post-TLA TATs to organism IDs (18.5 to 16.9 h), AST results (41.8 to 40.8 h), and preliminary results for negative cultures (17.7 to 13.6 h), including interquartile ranges for all comparisons, were significantly decreased post-TLA (P < 0.001). By the comparison II results, MALDI significantly improved TAT to organism ID compared to CONV (21.3 to 18 h). TLA further improved overall TAT to ID (18 to 16.5 h) and AST (42.3 to 40.7 h) results compared to MALDI (P < 0.001). In summary, TLA significantly improved TAT to organism ID, AST report, and preliminary negative results. MALDI-TOF MS significantly improved TAT for organism ID. Use of MALDI-TOF MS and TLA individually and together results in significant decreases in microbiology report TATs. PMID:29118171
Microcolony culture techniques for tuberculosis diagnosis: a systematic review.
Leung, E; Minion, J; Benedetti, A; Pai, M; Menzies, D
2012-01-01
There is considerable demand for quicker and more affordable yet accurate diagnostic tools for tuberculosis (TB). The microscopic observation drug susceptibility (MODS) assay and the thin-layer agar (TLA) assay are inexpensive, rapid microcolony-based culture methods. A systematic review and meta-analysis was performed to assess the accuracy and other test characteristics of MODS and TLA compared to a reference standard of traditional solid or liquid culture. Pooled estimates of sensitivity and specificity and their 95% confidence intervals were estimated with an exact binomial likelihood random effects meta-analysis. A total of 21 eligible studies were identified, 12 that evaluated MODS, seven that evaluated TLA and two that evaluated both. The overall pooled sensitivity and specificity of MODS were respectively 92% (95%CI 87-97) and 96% (90-100), and for TLA they were respectively 87% (95%CI 79-94) and 98% (95%CI 94-100), although there was considerable heterogeneity of results. When the studies were restricted to those assessing accuracy of MODS in sputum samples only, the sensitivity was 96% (95%CI 94-98) and the specificity 96% (95%CI 89-100). The mean intervals from reception of specimens to results were 9.2 days with MODS and 11.5 days with TLA; contamination rates averaged 6.6% with MODS and 12.3% with TLA; materials and supplies costs averaged US$1.48 for MODS and US$2.42 for TLA. MODS and TLA appear to be accurate and rapid yet inexpensive diagnostic tools for active TB. However, this review did not find sufficient evidence on the feasibility and costs of implementation of these tests, nor on the impact of these tests on patient outcomes.
Timeline analysis program (TLA-1), appendices
NASA Technical Reports Server (NTRS)
Miller, K. H.
1976-01-01
Appendices for the Timeline Analysis Program (TLA-1) were given. The appendices contain the Atlanta terminal area scenarios, the task catalog and the control and display configurations for the forward and aft flight decks of the NASA 515 aircraft, and the event/procedure, phase, mission, and subsystem catalogs.
Brazier, Peter; Schauer, Uwe; Hamelmann, Eckard; Holmes, Steve; Pritchard, Clive; Warner, John O
2016-01-01
Chronic asthma is a significant burden for individual sufferers, adversely impacting their quality of working and social life, as well as being a major cost to the National Health Service (NHS). Temperature-controlled laminar airflow (TLA) therapy provides asthma patients at BTS/SIGN step 4/5 an add-on treatment option that is non-invasive and has been shown in clinical studies to improve quality of life for patients with poorly controlled allergic asthma. The objective of this study was to quantify the cost-effectiveness of TLA (Airsonett AB) technology as an add-on to standard asthma management drug therapy in the UK. The main performance measure of interest is the incremental cost per quality-adjusted life year (QALY) for patients using TLA in addition to usual care versus usual care alone. The incremental cost of TLA use is based on an observational clinical study monitoring the incidence of exacerbations with treatment valued using NHS cost data. The clinical effectiveness, used to derive the incremental QALY data, is based on a randomised double-blind placebo-controlled clinical trial comprising participants with an equivalent asthma condition. For a clinical cohort of asthma patients as a whole, the incremental cost-effectiveness ratio (ICER) is £8998 per QALY gained, that is, within the £20 000/QALY cost-effectiveness benchmark used by the National Institute for Health and Care Excellence (NICE). Sensitivity analysis indicates that ICER values range from £18 883/QALY for the least severe patients through to TLA being dominant, that is, cost saving as well as improving quality of life, for individuals with the most severe and poorly controlled asthma. Based on our results, Airsonett TLA is a cost-effective addition to treatment options for stage 4/5 patients. For high-risk individuals with more severe and less well controlled asthma, the use of TLA therapy to reduce incidence of hospitalisation would be a cost saving to the NHS.
Tumour-like anomaly of copepods-an evaluation of the possible causes in Indian marine waters.
Jagadeesan, L; Jyothibabu, R
2016-04-01
Globally, tumour-like anomalies (TLA) in copepods and the critical assessment of their possible causes are rare. The exact causative factor and ecological consequences of TLA in copepods are still unclear and there is no quantitative data available so far to prove conclusively the mechanism involved in developing TLA in copepods. TLA in copepods are considered as a potential threat to the well-being of the aquatic food web, which prompted us to assess these abnormalities in Indian marine waters and assess the possible etiological agents. We carried out a focused study on copepods collected from 10 estuarine inlets and five coastal waters of India using a FlowCAM, advanced microscopes and laboratory-incubated observations. The analysis confirmed the presence of TLA in copepods with varying percentage of incidence in different environments. TLA was recorded in 24 species of copepods, which constituted ~1-15 % of the community in different environments. TLA was encountered more frequently in dominant copepods and exhibited diverse morphology; ~60 % was round, dark and granular, whereas ~20 % was round/oval, transparent and non-granular. TLA was mostly found in the dorsal and lateral regions of the prosome of copepods. The three suggested reasons/assumptions about the causes of TLA such as ecto-parasitism (Ellobiopsis infection), endo-parasitism (Blastodinium infection) and epibiont infections (Zoothamnium and Acineta) were assessed in the present study. We did find infections of endo-parasite Blastodinium, ecto-parasite Ellobiopsis and epibiont Zoothamnium and Acineta in copepods, but these infectious percentages were found <1.5 % to the total density and most of them are species specific. Detailed microscopical observations of the samples collected and the results of the incubation experiments of infected copepods revealed that ecto-parasitism, endo-parasitism and epibiont infections have less relevance to the formation of TLA in copepods. On the other hand, these studies corroborated the view that wounds on the exoskeleton caused by partial predation as the potential reason for the TLA of copepods in Indian waters.
Expression of mouse Tla region class I genes in tissues enriched for gamma delta cells.
Eghtesady, P; Brorson, K A; Cheroutre, H; Tigelaar, R E; Hood, L; Kronenberg, M
1992-01-01
The Tla region of the BALB/c mouse major histocompatibility complex contains at least 20 class I genes. The function of the products of these genes is unknown, but recent evidence demonstrates that some Tla region gene products could be involved in presentation of antigens to gamma delta T cells. We have generated a set of polymerase chain reaction (PCR) oligonucleotide primers and hybridization probes that permit us to specifically amplify and detect expression of 11 of the 20 BALB/c Tla region genes. cDNA prepared from 12 adult and fetal tissues and from seven cell lines was analyzed. In some cases, northern blot analysis or staining with monoclonal antibodies specific for the Tla-encoded thymus leukemia (TL) antigen were used to confirm the expression pattern of several of the genes as determined by PCR. Some Tla region genes, such as T24d and the members of the T10d/T22d gene pair, are expressed in a wide variety of tissues in a manner similar to the class I transplantation antigens. The members of the TL antigen encoding gene pair, T3d/T18d, are expressed in only a limited number of organs, including several sites enriched for gamma delta T cells. Other Tla region genes, including T1d, T2d, T16d, and T17d, are transcriptionally silent and transcripts from the T8d/T20d gene pair do not undergo proper splicing. In general, sites that contain gamma delta T lymphocytes have Tla region transcripts. The newly identified pattern of expression of the genes analyzed in sites containing gamma delta T cells further extends the list of potential candidates for antigen presentation to gamma delta T cells.
Brazier, Peter; Schauer, Uwe; Hamelmann, Eckard; Holmes, Steve; Pritchard, Clive; Warner, John O
2016-01-01
Introduction Chronic asthma is a significant burden for individual sufferers, adversely impacting their quality of working and social life, as well as being a major cost to the National Health Service (NHS). Temperature-controlled laminar airflow (TLA) therapy provides asthma patients at BTS/SIGN step 4/5 an add-on treatment option that is non-invasive and has been shown in clinical studies to improve quality of life for patients with poorly controlled allergic asthma. The objective of this study was to quantify the cost-effectiveness of TLA (Airsonett AB) technology as an add-on to standard asthma management drug therapy in the UK. Methods The main performance measure of interest is the incremental cost per quality-adjusted life year (QALY) for patients using TLA in addition to usual care versus usual care alone. The incremental cost of TLA use is based on an observational clinical study monitoring the incidence of exacerbations with treatment valued using NHS cost data. The clinical effectiveness, used to derive the incremental QALY data, is based on a randomised double-blind placebo-controlled clinical trial comprising participants with an equivalent asthma condition. Results For a clinical cohort of asthma patients as a whole, the incremental cost-effectiveness ratio (ICER) is £8998 per QALY gained, that is, within the £20 000/QALY cost-effectiveness benchmark used by the National Institute for Health and Care Excellence (NICE). Sensitivity analysis indicates that ICER values range from £18 883/QALY for the least severe patients through to TLA being dominant, that is, cost saving as well as improving quality of life, for individuals with the most severe and poorly controlled asthma. Conclusions Based on our results, Airsonett TLA is a cost-effective addition to treatment options for stage 4/5 patients. For high-risk individuals with more severe and less well controlled asthma, the use of TLA therapy to reduce incidence of hospitalisation would be a cost saving to the NHS. PMID:27026803
Validation of the GILLS score for tongue-lip adhesion in Robin sequence patients.
Abramowicz, Shelly; Bacic, Janine D; Mulliken, John B; Rogers, Gary F
2012-03-01
The GILLS score consists of gastroesophageal reflux disease, preoperative intubation, late surgical intervention, low birth weight, and syndromic diagnosis. The purpose of this study was to test the validity of the GILLS score in predicting success of tongue-lip adhesion (TLA) in managing Robin sequence. Infants with Robin sequence were included in the study if they had a TLA for airway compromise subsequent to formulation of the GILLS scoring system, that is, they were not included in the original GILLS analysis. The patients were prospectively considered based on the presence of the 5 factors that constitute the GILLS score. A score of ≤ 2 predicts success of TLA. Twenty patients met the inclusion criteria. Tongue-lip adhesion managed the compromised airway in 18 (90%) of 20 patients. Overall, the GILLS score had a sensitivity of 83%, specificity of 50%, positive predictive value of 94%, and negative predictive value of 25%. The GILLS score accurately predicts a successful outcome for TLA in infants with Robin sequence. For infants with a score of 2 or less, TLA is the procedure of choice. Infants with a GILLS score of 3 or greater were 5 times more likely to fail TLA than those with a score of 2 or less. In these patients, other methods of managing the airway should be considered.
Stoffels, I; Dissemond, J; Körber, A; Hillen, U; Poeppel, T; Schadendorf, D; Klode, J
2011-03-01
Sentinel lymph node excision (SLNE) for the detection of regional nodal metastases and staging of malignant melanoma has resulted in some controversies in international discussions, as it is a cost-intensive surgical intervention with potentially significant morbidity. The present retrospective study seeks to clarify the effectiveness and reliability of SLNE performed under tumescent local anaesthesia (TLA) and whether SLNE performed under TLA can reduce costs and morbidity. Therefore, our study is a comparison of SLNE performed under TLA and general anaesthesia (GA). We retrospectively analysed data from 300 patients with primary malignant melanoma with a Breslow index of ≥1.0 mm. Altogether, 211 (70.3%) patients underwent SLNE under TLA and 89 (29.7%) patients underwent SLNE under GA. A total of 637 sentinel lymph nodes (SLN) were removed. In the TLA group 1.98 SLN/patient and in the GA group 2.46 SLN/patient were removed (median value). Seventy patients (23.3%) had a positive SLN. No major complications occurred. The costs for SLNE were significantly less for the SLNE in a procedures room performed under TLA (mean € 30.64) compared with SLNE in an operating room under GA (mean € 326.14, P<0.0001). In conclusion, SLNE performed under TLA is safe, reliable, and cost-efficient and could become the new gold standard in sentinel lymph node diagnostic procedures. © 2010 The Authors. Journal of the European Academy of Dermatology and Venereology © 2010 European Academy of Dermatology and Venereology.
Ratti, Francesca; Catena, Marco; Di Palo, Saverio; Staudacher, Carlo; Aldrighetti, Luca
2016-11-01
Thanks to widespread diffusion of minimally invasive approach in the setting of both colorectal and hepatic surgeries, the interest in combined resections for colorectal cancer and synchronous liver metastases (SCLM) by totally laparoscopic approach (TLA) has increased. Aim of this study was to compare outcome of combined resections for SCLM performed by TLA or by open approach, in a propensity-score-based study. All 25 patients undergoing combined TLA for SCLM at San Raffaele Hospital in Milano were compared in a case-matched analysis with 25 out of 91 patients undergoing totally open approach (TOA group). Groups were matched with 1:2 ratio using propensity scores based on covariates representing disease severity. Main endpoints were postoperative morbidity and long-term outcome. The Modified Accordion Severity Grading System was used to quantify complications. The groups resulted comparable in terms of patients and disease characteristics. The TLA group, as compared to the TOA group, had lower blood loss (350 vs 600 mL), shorter postoperative stay (9 vs 12 days), lower postoperative morbidity index (0.14 vs 0.20) and severity score for complicated patients (0.60 vs 0.85). Colonic anastomosis leakage had the highest fractional complication burden in both groups. In spite of comparable long-term overall survival, the TLA group had better recurrence-free survival. TLA for combined resections is feasible, and its indications can be widened to encompass a larger population of patients, provided its benefits in terms of reduced overall risk and severity of complications, rapid functional recovery and favorable long-term outcomes.
Population pharmacokinetic model for tumescent lidocaine in women undergoing breast cancer surgery.
Riff, Camille; Bourgoin, Aurélie; Marsot, Amelie; Allanioux, Laurent; Leone, Marc; Blin, Olivier; Guilhaumou, Romain
2018-06-16
Tumescent lidocaine anesthesia (TLA) is an opportunity to perform mastectomy for breast cancer without general anesthesia in elderly women. Few reports are available on the pharmacokinetics of lidocaine in a context of TLA during a unilateral mastectomy. The aim of this study was to describe lidocaine pharmacokinetics in elderly women undergoing breast cancer surgery after TLA and to explore the risk of the toxicity of this technique. A prospective study was conducted to examine the pharmacokinetics of lidocaine in women undergoing TLA. TLA consists of an intradermal lidocaine instillation (20 mL, 1% [200 mg]) followed by a tumescent lidocaine infiltration (100 mL of 1% lidocaine [1000 mg] and 0.5 mg epinephrine to 1 L Ringer's lactate) via an infusion pump. A population pharmacokinetic (popPK) analysis was performed using the nonlinear mixed effects model (NONMEM). The analysis included 116 observations from 17 women with a median (range) age of 83.4 (60.5-90.0). The median tumescent lidocaine dose was 800 mg (range 375-1000 mg) infused over 48.0 ± 11.0 min. A one-compartment disposition model with first order absorption, two input compartments, and a central elimination best described the pharmacokinetics of lidocaine. The estimates (between subject variability; relative standard error, %) of apparent volume, apparent clearance, tumescent absorption rate, and instillation absorption rate were 195.0 (46.3; 14.5%) L, 24.7 (48.9; 13.3%) L h -1 , 0.28 (39.6; 13.8%) h -1 , and 2.56 (135.3; 44.9%) h -1 , respectively. This is the first popPK model developed to describe kinetic profiles of TLA. These findings confirm the slow diffusion of lidocaine from the tumescent deposit.
Klein, Sabrina; Nurjadi, Dennis; Horner, Susanne; Heeg, Klaus; Zimmermann, Stefan; Burckhardt, Irene
2018-04-13
While total laboratory automation (TLA) is well established in laboratory medicine, only a few microbiological laboratories are using TLA systems. Especially in terms of speed and accuracy, working with TLA is expected to be superior to conventional microbiology. We compared in total 35,564 microbiological urine cultures with and without incubation and processing with BD Kiestra TLA for a 6-month period each retrospectively. Sixteen thousand three hundred thirty-eight urine samples were analyzed in the pre-TLA period and 19,226 with TLA. Sixty-two percent (n = 10,101/16338) of the cultures processed without TLA and 68% (n = 13,102/19226) of the cultures processed with TLA showed growth. There were significantly more samples with two or more species per sample and with low numbers of colony forming units (CFU) after incubation with TLA. Regarding the type of bacteria, there were comparable amounts of Enterobacteriaceae in the samples, slightly less non-fermenting Gram-negative bacteria, but significantly more Gram-positive cocci, and Gram-positive rods. Especially Alloscardivia omnicolens, Gardnerella vaginalis, Actinomyces spp., and Actinotignum schaalii were significantly more abundant in the samples incubated and processed with TLA. The time to report was significantly lower in the TLA processed samples by 1.5 h. We provide the first report in Europe of a large number of urine samples processed with TLA. TLA showed enhanced growth of non-classical and rarely cultured bacteria from urine samples. Our findings suggest that previously underestimated bacteria may be relevant pathogens for urinary tract infections. Further studies are needed to confirm our findings.
TLA+: Whence, Wherefore, and Whither
NASA Technical Reports Server (NTRS)
Lamport, Leslie
2009-01-01
The evolution of my ideas on specification and verification, and how they led to the TLA+ specification language. What is good and bad about TLA+. A brief description of the next version of TLA+ and its tools. E.
Yang, M P; Goitsuka, R; Ono, K; Suzuki, N; Hasegawa, A
1990-08-01
The cytotoxic activities of feline spleen cells treated with Toxoplasma lysate antigen (TLA) were assayed against feline leukemia virus (FeLV)-producing lymphoma. FL74 cells, and xenogeneic target lymphoma, mouse YAC-1 cells. The TLA treatments were performed in vivo alone, in vitro alone, and in vivo plus in vitro, respectively. In vivo plus in vitro treatments with TLA induced a marked augmentation in cytotoxic activity of spleen cells to FL74 cells. The treatment with TLA in vivo alone showed an enhancement of cytotoxic activity but in vitro alone did not. The cytotoxic effects of TLA-treated spleen cells obtained from the cats which had been previously immunized with live FL74 cells were similar to those of spleen cells from non-immunized cats treated with TLA. However, no increase of cytotoxicity was shown in the response to mouse YAC-1 cells regardless of TLA treatments. These results indicated that the in vivo TLA treatment augmented the cytotoxicity of feline spleen cells against FeLV-producing lymphoma cell.
Kirst, Henning; Garcia-Cerdan, Jose Gines; Zurbriggen, Andreas; Ruehle, Thilo; Melis, Anastasios
2012-01-01
The truncated light-harvesting antenna size3 (tla3) DNA insertional transformant of Chlamydomonas reinhardtii is a chlorophyll-deficient mutant with a lighter green phenotype, a lower chlorophyll (Chl) per cell content, and higher Chl a/b ratio than corresponding wild-type strains. Functional analyses revealed a higher intensity for the saturation of photosynthesis and greater light-saturated photosynthetic activity in the tla3 mutant than in the wild type and a Chl antenna size of the photosystems that was only about 40% of that in the wild type. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western-blot analyses showed that the tla3 strain was deficient in the Chl a/b light-harvesting complex. Molecular and genetic analyses revealed a single plasmid insertion in chromosome 4 of the tla3 nuclear genome, causing deletion of predicted gene g5047 and plasmid insertion within the fourth intron of downstream-predicted gene g5046. Complementation studies defined that gene g5047 alone was necessary and sufficient to rescue the tla3 mutation. Gene g5047 encodes a C. reinhardtii homolog of the chloroplast-localized SRP43 signal recognition particle, whose occurrence and function in green microalgae has not hitherto been investigated. Biochemical analysis showed that the nucleus-encoded and chloroplast-localized CrCpSRP43 protein specifically operates in the assembly of the peripheral components of the Chl a/b light-harvesting antenna. This work demonstrates that cpsrp43 deletion in green microalgae can be employed to generate tla mutants with a substantially diminished Chl antenna size. The latter exhibit improved solar energy conversion efficiency and photosynthetic productivity under mass culture and bright sunlight conditions. PMID:23043081
Lymph node dissection for melanoma using tumescence local anaesthesia: an observational study.
Kofler, Lukas; Breuninger, Helmut; Häfner, Hans-Martin; Schweinzer, Katrin; Schnabl, Saskia M; Eigentler, Thomas K; Leiter, Ulrike
2018-04-01
The possibility that tumescence local anaesthesia (TLA) may lead to dissemination of tumour cells in lymph nodes is presently unclear. To evaluate whether infiltration by TLA influences metastatic spread and survival probability, compared to general anaesthesia (GA), based on lymph node dissection in melanoma patients. In total, 281 patients (GA: 162; TLA: 119) with cutaneous melanoma and clinically or histologically-confirmed metastases in regional lymph nodes were included. All patients underwent complete lymph node dissection. Median follow-up was 70 months. The rate of lymph node recurrence at the dissection site was 25.3% in the GA group and 17.6% in the TLA group (p = 0.082). No significant difference was found concerning 10-year melanoma-specific survival (GA: 56.2%, TLA: 67.4%; p = 0.09), disease-free survival (GA: 72.8 %, TLA: 81.1%; p = 0.095), or lymph node-free survival (GA: 72.8%, TLA: 81.1%; p = 0.095). Distant metastases-free survival appeared to be slightly reduced in the TLA group (GA: 49.9%, TLA: 64.0%; p = 0.025). No differences were identified between the GA and TLA groups regarding prognostic outcome for overall survival or disease-free survival.
Investigations in structural morphological and optical properties of Bi-Pb-S system thin films
NASA Astrophysics Data System (ADS)
Malika, Boukhalfa; Noureddine, Benramdane; Mourad, Medles; Abdelkader, Outzourhit; Attouya, Bouzidi; Hind, Tabet-derraz
Bi2S3, PbS and Bi-Pb-S system thin films were grown on glass substrates by the spray pyrolysis technique. The films growth was realized by the reaction of aqueous solutions of bismuth trichloride (BiCl3) and trihydrate Lead Acetate (TLA) (Pb(CH3COO)2.3H2O) with thiourea on heated substrates. The films study was performed as a function of the TLA volume ratio (TLA vol. ratio) in the solution obtained by the mixture of BiCl3 and thiourea used as precursor solution (PrS). X-ray diffraction (XRD), field emitting scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS) were used for structural and compositional analysis of the as deposited films. With the structural investigations, Bi2S3, PbS thin films and PbS-Bi2S3 composite thin films formation was confirmed. Optical properties of the deposited films were obtained using transmittance and reflectance measurements in the wavelength range [200-2500 nm]. The absorption edge shows a shift towards low energy with the increase of the TLA vol. ratio.The optical bandgaps for the films with various TLA vol. ratio are found to lie between those of the Bi2S3 and PbS ones. The optical parameters (extinction coefficient, refractive index, real and imaginary parts if the complex dielectric constant) of the thin films are also investigated. These are found to be dependent on the TLA vol. ratio.
Safety of liposuction using exclusively tumescent local anesthesia in 3,240 consecutive cases.
Habbema, Louis
2009-11-01
Many surgeons consider liposuction using tumescent local anesthesia (TLA) to be a safe technique, but when TLA has been combined with other techniques, such as general anesthesia or intravenous medication, or when the guidelines associated with TLA have been violated, serious complications and deaths have occurred. This has resulted in uncertainty concerning the safety of liposuction using TLA, which this article seeks to resolve. To investigate whether liposuction using TLA is a safe procedure. The same surgeon performed liposuction using exclusively TLA in 3,240 procedures. Detailed records were kept of the complications that occurred. In a series of 3,240 procedures, no deaths occurred, and no complications requiring hospitalization were experienced. In nine cases, complications developed that needed further action. Liposuction using exclusively TLA is a proven safe procedure provided that the existing guidelines are meticulously followed.
Preparing for LISA Data: The Testbed for LISA Analysis Project
NASA Astrophysics Data System (ADS)
Finn, Lee Samuel; Benacquista, Matthew J.; Larson, Shane L.; Rubbo, Louis J.
2006-11-01
The Testbed for LISA Analysis (TLA) Project aims to facilitate the development, validation, and comparison of different methods for LISA science data analysis by the broad LISA Science Community to meet the special challenges that LISA poses. It includes a well-defined Simulated LISA Data Product (SLDP), which provides a clean interface between the modeling of LISA, the preparation of LISA data, and the analysis of the LISA science data stream; a web-based clearinghouse (at
The Surgical Treatment of Robin Sequence.
Greathouse, Shawn Travis; Costa, Melinda; Ferrera, Alessandra; Tahiri, Youssef; Tholpady, Sunil S; Havlik, Robert J; Flores, Roberto L
2016-10-01
We present an outcomes analysis of the surgical treatment of Robin sequence including all infants and comorbid conditions treated by tongue-lip adhesion (TLA) or mandibular distraction osteogenesis (MDO). A 19-year single-institution, multisurgeon retrospective review of all syndromic and nonsyndromic neonates with Robin sequence treated with TLA (1994-2004) or MDO (2004-2013) was performed. Comorbid conditions were recorded in all patients. Outcomes include incidence of tracheostomy, improvement in obstructive breathing, and surgical complications. Need for repeat distraction and conversion from TLA to MDO were included as secondary end-points. Polysomnography data were recorded preoperatively at 1 month and 1 year as a measure of airway improvement. Seventy-four MDO patients and 15 TLA patients during the study period met inclusion criteria. There was no significant difference in mean age at intervention (32.1 ± 29.0 vs 35.5 ± 32.1 days), birth weight (2.9 ± 0.7 vs 3.2 ± 0.6 kg), prematurity (23.0 vs 35.7%), or intrauterine growth restriction (31.1 vs 15.4%). Central nervous system anomalies (24.3% vs 0.0%; P < 0.04) and gastrostomy tubes (66.2% vs 33.3%; P < 0.03) were present more frequently in MDO patients versus TLA patients. Rates of other organ system anomalies were similar between the groups. The success rate was significantly higher in the MDO group (90.5% vs 60.0%; P < 0.008). Postoperative tracheostomies occurred in 8.1% of the MDO group and 33.3% of the TLA group (P < 0.02). Preoperative apnea-hyponea index was similar between the two groups (38.3 vs 38.1). The apnea-hyponea index was significantly improved in the MDO group at 1 month (4.0 vs 21.7; P < 0.002) and 1 year (5.7 vs 20.5; P < 0.005). Surgical complications were statistically less in the MDO group (20.3 vs 53.3%; P < 0.02). In the heterogeneous population of Robin sequence, MDO demonstrates superior outcomes measures at 1 month and 1 year compared to TLA. Fewer complications occurred in the MDO group compared to the TLA.
Hsiao, HaoYuan; Knarr, Brian A; Pohlig, Ryan T; Higginson, Jill S; Binder-Macleod, Stuart A
2016-02-08
Current rehabilitation efforts for individuals poststroke focus on increasing walking speed because it is a predictor of community ambulation and participation. Greater propulsive force is required to increase walking speed. Previous studies have identified that trailing limb angle (TLA) and ankle moment are key factors to increases in propulsive force during gait. However, no studies have determined the relative contribution of these two factors to increase propulsive force following intervention. The purpose of this study was to quantify the relative contribution of ankle moment and TLA to increases in propulsive force following 12-weeks of gait training for individuals poststroke. Forty-five participants were assigned to 1 of 3 training groups: training at self-selected speeds (SS), at fastest comfortable speeds (Fast), and Fast with functional electrical stimulation (FastFES). For participants who gained paretic propulsive force following training, a biomechanical-based model previously developed for individuals poststroke was used to calculate the relative contributions of ankle moment and TLA. A two-way, mixed-model design, analysis of covariance adjusted for baseline walking speed was performed to analyze changes in TLA and ankle moment across groups. The model showed that TLA was the major contributor to increases in propulsive force following training. Although the paretic TLA increased from pre-training to post-training, no differences were observed between groups. In contrast, increases in paretic ankle moment were observed only in the FastFES group. Our findings suggested that specific targeting may be needed to increase ankle moment. Copyright © 2016 Elsevier Ltd. All rights reserved.
Hsiao, HaoYuan; Knarr, Brian A.; Pohlig, Ryan T.; Higginson, Jill S.; Binder-Macleod, Stuart A.
2016-01-01
Current rehabilitation efforts for individuals poststroke focus on increasing walking speed because it is a predictor of community ambulation and participation. Greater propulsive force is required to increase walking speed. Previous studies have identified that trailing limb angle (TLA) and ankle moment are key factors to increases in propulsive force during gait. However, no studies have determined the relative contribution of these two factors to increase propulsive force following intervention. The purpose of this study was to quantify the relative contribution of ankle moment and TLA to increases in propulsive force following 12-weeks of gait training for individuals poststroke. Forty-five participants were assigned to 1 of 3 training groups: training at self-selected speeds (SS), at fastest comfortable speeds (Fast), and Fast with functional electrical stimulation (FastFES). For participants who gained paretic propulsive force following training, a biomechanical-based model previously developed for individuals poststroke was used to calculate the relative contributions of ankle moment and TLA. A two-way, mixed-model design, analysis of covariance adjusted for baseline walking speed was performed to analyze changes in TLA and ankle moment across groups. The model showed that TLA was the major contributor to increases in propulsive force following training. Although the paretic TLA increased from pre-training to post-training, no differences were observed between groups. In contrast, increases in paretic ankle moment were observed only in the FastFES group. Our findings suggested that specific targeting may be needed to increase ankle moment. PMID:26776931
TLA-2, a novel Ambler class A expanded-spectrum beta-lactamase.
Girlich, Delphine; Poirel, Laurent; Schlüter, Andreas; Nordmann, Patrice
2005-11-01
Beta-lactamase TLA-2 is encoded by a 47-kb plasmid isolated from an unidentified bacterial strain from a wastewater treatment plant. TLA-2 is an Ambler class A beta-lactamase that shares 52% amino acid identity with CGA-1 from Chryseobacterium gleum and 51% with TLA-1 from Escherichia coli. The enzyme hydrolyzes mostly cephalosporins.
Kwee, Sandi A.; Lim, John; Watanabe, Alex; Kromer-Baker, Kathleen; Coel, Marc N.
2015-01-01
This study investigates the prognostic significance of metabolically active tumor volume (MATV) measurements applied to fluorine-18 fluorocholine (FC) PET/CT in castrate-resistant prostate cancer (CRPC). Methods FC PET/CT imaging was performed in 30 patients with CRPC. Metastatic disease was quantified on the basis of maximum standardized uptake value (SUVmax), MATV, and total lesion activity (TLA = MATV × mean SUV). Tumor burden indices derived from whole-body summation of PET tumor volume measurements (ie. net MATV and net TLA) were evaluated as variables in Cox regression and Kaplan-Meier survival analyses. Results Net MATV ranged from 0.12 cm3 to 1543.9 cm3 (median 52.6 cm3). Net TLA ranged from 0.40g to 6688.7g (median 225.1g). PSA level at the time of PET correlated significantly with net MATV (Pearson r = 0.65, p = 0.0001) and net TLA (r = 0.60, p = 0.0005) but not highest lesional SUVmax of each scan. Survivors were followed for a median 23 months (range 6 – 38 months). On Cox regression analyses, overall survival was significantly associated with net MATV (p = 0.0068), net TLA (p = 0.0072), and highest lesion SUVmax (p = 0.0173), and borderline associated with PSA level (p = 0.0458). Only net MATV and net TLA remained significant in univariate-adjusted survival analyses. Kaplan-Meier analysis demonstrated significant differences in survival between groups stratified by median net MATV (log-rank P = 0.0371), net TLA (log-rank P = 0.0371), and highest lesion SUVmax (log-rank P = 0.0223). Conclusions Metastatic prostate cancer detected by FC PET/CT can be quantified based on volumetric measurements of tumor metabolic activity. The prognostic value of FC PET/CT may stem from this capacity to assess whole-body tumor burden. With further clinical validation, FC PET-based indices of global disease activity and mortality risk could prove useful in patient-individualized treatment of CRPC. PMID:24676753
TLA-2, a Novel Ambler Class A Expanded-Spectrum β-Lactamase
Girlich, Delphine; Poirel, Laurent; Schlüter, Andreas; Nordmann, Patrice
2005-01-01
β-Lactamase TLA-2 is encoded by a 47-kb plasmid isolated from an unidentified bacterial strain from a wastewater treatment plant. TLA-2 is an Ambler class A β-lactamase that shares 52% amino acid identity with CGA-1 from Chryseobacterium gleum and 51% with TLA-1 from Escherichia coli. The enzyme hydrolyzes mostly cephalosporins. PMID:16251326
Vija Racaru, Lavinia; Sinigaglia, Mathieu; Kanoun, Salim; Ben Bouallègue, Fayçal; Tal, Ilan; Brillouet, Sévérine; Bauriaud-Mallet, Mathilde; Zerdoud, Slimane; Dierickx, Lawrence; Vallot, Delphine; Caselles, Olivier; Gabiache, Erwan; Pascal, Pierre; Courbon, Frederic
2018-05-21
This study aims to predict hematological toxicity induced by Ra therapy. We investigated the value of metabolically active bone tumor volume (MBTV) and total bone lesion activity (TLA) calculated on pretreatment fluorine-18-fluorocholine (F-FCH) PET/CT in castrate-resistant prostate cancer (CRPC) patients with bone metastases treated with Ra radionuclide therapy. F-FCH PET/CT imaging was performed in 15 patients with CRPC before treatment with Ra. Bone metastatic disease was quantified on the basis of the maximum standardized uptake value (SUV), total lesion activity (TLA=MBTV×SUVmean), or MBTV/height (MBTV/H) and TLA/H. F-FCH PET/CT bone tumor burden and activity were analyzed to identify which parameters could predict hematological toxicity [on hemoglobin (Hb), platelets (PLTs), and lymphocytes] while on Ra therapy. Pearson's correlation was used to identify the correlations between age, prostate-specific antigen, and F-FCH PET parameters. MBTV ranged from 75 to 1259 cm (median: 392 cm). TLA ranged from 342 to 7198 cm (median: 1853 cm). Patients benefited from two to six cycles of Ra (n=56 cycles in total). At the end of Ra therapy, five of the 15 (33%) patients presented grade 2/3 toxicity on Hb and lymphocytes, whereas three of the 15 (20%) patients presented grade 2/3 PLT toxicity.Age was correlated negatively with both MBTV (r=-0.612, P=0.015) and TLA (r=-0.596, P=0.018). TLA, TLA/H, and MBTV/H predicted hematological toxicity on Hb, whereas TLA/H and MBTV/H predicted toxicity on PLTs at the end of Ra cycles. Receiver operating characteristic curve analysis allowed to define the cutoffs for MBTV (915 cm) and TLA (4198 cm) predictive for PLT toxicity, with an accuracy of 0.92 and 0.99. Tumor bone burden calculation is feasible with F-FCH PET/CT with freely available open-source software. In this pilot study, baseline F-FCH PET/CT markers (TLA, MBTV) have shown abilities to predict Hb and PLT toxicity after Ra therapy and could be explored for patient selection and treatment optimization.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. http://creativecommons.org/licenses/by-nc-nd/4.0/.
Bayhan, Ilhan A; Beng, Kubilay; Yildirim, Timur; Akpinar, Evren; Ozcan, Cagri; Yagmurlu, Firat
2016-11-01
The aim of this study was to compare the midterm clinical and radiological outcomes of the Salter osteotomy (SO) and Tonnis lateral acetabuloplasty (TLA) with concomitant open reduction for the treatment of developmental dysplasia of the hip. Twenty-five hips of 20 patients who underwent SO with open reduction and 26 hips of 23 patients who underwent TLA with open reduction were evaluated retrospectively. The average age of the patients at the time of the operation was 35.6 months in the SO and 36.6 months in the TLA group, without a statistically significant difference (P=0.836). The average follow-up times in the SO and TLA groups were 59.9 and 54.8 months, respectively (P=0.397). Preoperative (40.6° in the SO vs. 42.2° in the TLA, P=0.451) and last follow-up acetabular index (12° in the SO vs. 14° in the TLA, P=0.227) and center-edge angle measurements (30° in the SO vs. 26° in the TLA, P=0.069) did not show a statistically significant difference between the SO and TLA groups; however, early postoperative acetabular index improvement was better in the TLA group than in the SO group (21.2° in the SO vs. 17.2° in the TLA, P=0.014). According to the Severin grading system, both groups showed a similar number of good outcomes without a statistically significant difference (P=0.936). Clinical assessment on the basis of McKay's criteria showed similar good and excellent outcomes (P=0.936). Both osteotomy techniques showed similar satisfactory outcomes for the treatment of DDH in patients older than 18 months of age.
Kagiyama, Nobuyuki; Hayashida, Akihiro; Toki, Misako; Fukuda, Shota; Ohara, Minako; Hirohata, Atsushi; Yamamoto, Keizo; Isobe, Mitsuaki; Yoshida, Kiyoshi
2017-03-01
The relationship between annular dilatation caused by atrial fibrillation (AF) and mitral regurgitation (MR) remains controversial. We hypothesized that the small ratio of total leaflet area/annulus area (TLA/AA), reflecting insufficient leaflet remodeling to annular dilatation, is a main component of MR in patients with AF. Three-dimensional transesophageal echocardiographic data of the mitral valve were analyzed in 28 AF patients with moderate or severe MR (MR group), age- and sex-matched 56 AF patients with mild or less MR (non-MR group), and 16 control subjects. AA was significantly greater in both the MR (645±126 mm 2 /m 2 , P <0.001) and non-MR groups (568±121 mm 2 /m 2 , P =0.001) compared with control subjects (444±108 mm 2 /m 2 ). However, TLA/AA was significantly smaller in the MR (1.29±0.10, P <0.001), but not in the non-MR group (1.65±0.24, P >0.99), compared with control subjects (1.70±0.29). In linear regression analysis, TLA/AA was inversely associated with the effective regurgitant orifice ( r =-0.73, P <0.001). The area under the receiver-operating-characteristics curve of TLA/AA was significantly greater than that of AA (0.95 versus 0.72, P <0.001). Multivariable analysis revealed that small TLA/AA ( P <0.001) was independently associated with significant MR, while AA was not ( P =0.26). In patients with AF, insufficient leaflet remodeling to annular dilatation, rather than crude annular dilatation, was strongly associated with the severity of MR. © 2017 American Heart Association, Inc.
Papoff, P; Guelfi, G; Cicchetti, R; Caresta, E; Cozzi, D A; Moretti, C; Midulla, F; Miano, S; Cerasaro, C; Cascone, P
2013-11-01
The objective was to review and compare outcomes after tongue-lip adhesion (TLA) and mandibular distraction osteogenesis (MDO) in infants with severe breathing difficulties related to Pierre Robin sequence (PRS). A single-centre retrospective (2002-2012) study was carried out; 18 infants with severe breathing difficulties related to PRS resistant to conservative treatment, who underwent TLA or MDO to correct airway obstruction, were enrolled. The primary outcome measures were successful weaning from respiratory support and resumption of full oral feeding. Nine underwent TLA and nine MDO. Eight of the nine infants who underwent MDO and all those treated with TLA were successfully weaned from respiratory support. After discharge, residual respiratory distress was diagnosed more commonly after TLA than after MDO (6/9 vs 1/9, P=0.050). Infants resumed oral feeding sooner after MDO than after TLA (mean days after surgery to full oral feeds 44±24 vs 217±134, P<0.003). The length of hospital stay was longer for infants treated with MDO than for those treated with TLA. The rate of complications was similar. Infants with severe airway obstruction related to PRS can benefit safely from either TLA or MDO. Although MDO lengthens the time to discharge, this option stabilizes airway patency of infants with PRS more efficiently and achieves full oral feeding more rapidly than TLA. Copyright © 2013 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Statistical analysis of the calibration procedure for personnel radiation measurement instruments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bush, W.J.; Bengston, S.J.; Kalbeitzer, F.L.
1980-11-01
Thermoluminescent analyzer (TLA) calibration procedures were used to estimate personnel radiation exposure levels at the Idaho National Engineering Laboratory (INEL). A statistical analysis is presented herein based on data collected over a six month period in 1979 on four TLA's located in the Department of Energy (DOE) Radiological and Environmental Sciences Laboratory at the INEL. The data were collected according to the day-to-day procedure in effect at that time. Both gamma and beta radiation models are developed. Observed TLA readings of thermoluminescent dosimeters are correlated with known radiation levels. This correlation is then used to predict unknown radiation doses frommore » future analyzer readings of personnel thermoluminescent dosimeters. The statistical techniques applied in this analysis include weighted linear regression, estimation of systematic and random error variances, prediction interval estimation using Scheffe's theory of calibration, the estimation of the ratio of the means of two normal bivariate distributed random variables and their corresponding confidence limits according to Kendall and Stuart, tests of normality, experimental design, a comparison between instruments, and quality control.« less
Robledo, J; Mejia, G I; Paniagua, L; Martin, A; Guzmán, A
2008-12-01
We evaluated thin-layer agar (TLA) for the detection of resistance of Mycobacterium tuberculosis to rifampicin (RMP) and isoniazid (INH) as a direct method in patients at risk of multidrug-resistant tuberculosis (MDR-TB). Quadrant TLA plates contain 7H10 Middlebrook growth control, para-nitrobenzoic acid, INH and RMP. Detection of RMP and INH resistance by TLA was compared to that in indirect conventional drug susceptibility testing (DST) and conventional culture media. Median time for growth was respectively 22, 10 and 7.6 days for Löwenstein-Jensen, TLA and the Mycobacterial Growth Indicator Tube. TLA sensitivity, specificity and predictive values for RMP and INH resistance were 100%. Time to resistance detection was respectively 11 and 11.5 days for RMP and INH. TLA showed a rapid turnaround time and performance comparable to conventional DST methods.
Sasaji, Tatsuro; Kawahara, Chikashi; Matsumoto, Fujio
2011-01-01
A case of ossification of transverse ligament of atlas (TLA) is reported. A 76-year-old female suffered from a transverse type myelopathy was successfully treated by posterior decompression. Dynamic lateral plain radiographs showed irreducible atlantoaxial subluxation (AAS). A computed tomogram revealed ossified mass compatible to ossification of TLA. Coalition of the atlantooccipital joints and osteoarthritis of the atlantoaxial joints with degenerated dens was also revealed. Magnetic resonance imaging showed compressed spinal cord at C1 level by the ossification of TLA and AAS. We suggest a mechanism of ossification of TLA as follows: hypertrophied dens and stress to the atlantoaxial joints caused by coalition of atlantooccipital joints could make forward shift of atlas leading to irreducible AAS, and continuous tension given to TLA from irreducible AAS would result in hypertrophied and ossification of TLA.
Afilalo, Jonathan; Grapsa, Julia; Nihoyannopoulos, Petros; Beaudoin, Jonathan; Gibbs, J. Simon R.; Channick, Richard N.; Langleben, David; Rudski, Lawrence G.; Hua, Lanqi; Handschumacher, Mark D.; Picard, Michael H.; Levine, Robert A.
2015-01-01
Background Tricuspid regurgitation (TR) is a risk factor for mortality in pulmonary hypertension (PH). TR severity varies among patients with comparable degrees of PH and right ventricular (RV) remodeling. The contribution of leaflet adaptation to the pathophysiology of TR has yet to be examined. We hypothesized that tricuspid leaflet area (TLA) is increased in PH, and that its size relative to RV remodeling determines TR severity. Methods and Results A prospective cohort of 255 patients with PH from pre- and post-capillary etiologies was assembled from two centers. Patients underwent a 3-D echocardiogram focused on the tricuspid apparatus. TLA was measured with the Omni custom software package. Compared with normal controls, PH patients had a twofold increase in RV volumes, 62% increase in annulus area, and 49% increase in TLA. Those with severe TR demonstrated inadequate increase in TLA relative to the closure area, such that the ratio of TLA-to-closure area <1.78 was highly predictive of severe TR (odds ratio 68.7; 95% CI 16.2, 292.7). The median vena contracta width was 8.5 mm in the group with small TLA and large closure area as opposed to 4.8 mm in the group with large TLA and large closure area. Conclusions TLA plays a significant role in determining which patients with PH develop severe functional TR. The ratio of TLA-to-closure area, reflecting the balance between leaflet adaptation vs. annular dilation and tethering forces, is an indicator of TR severity that may identify which patients stand to benefit from leaflet augmentation during tricuspid valve repair. PMID:25977303
Donmez, Turgut; Hut, Adnan; Avaroglu, Huseyin; Uzman, Sinan; Yildirim, Dogan; Ferahman, Sina; Cekic, Erdinc
2016-08-01
The 2-port laparoscopic appendectomy technique (TLA) is between the conventional 3-port and single-port laparoscopic appendectomy surgeries. We compared postoperative pain and cosmetic results after TLA with conventional laparoscopic appendectomy (CLA) by a 3-port device. Patients undergoing TLA were matched with patients undergoing CLA between February 2015 and November 2015 at the same institution. Thirty-two patients underwent TLA with a needle grasper. The appendix was secured by a percutaneous organ-holding device (needle grasper), then removed through a puncture at McBurney's point. Another 38 patients underwent CLA. Patient demographics, operative details, and postoperative outcomes were collected and evaluated. One patient in the TLA group developed a wound infection and 1 patient in the CLA group developed a postoperative intra-abdominal abscess and 3 wound infections. There was no significant difference between the groups when comparing the length of hospital stay, time until oral intake, and other complications. The pain score in the first 12 hours after surgery was significanly higher in CLA group than the TLA group (P < 0.001). Operative time was significantly shorter in the CLA group compared to the TLA group (P < 0.001). TLA using a needle grasper was associated with a significantly lower pain score 12 hours after surgery, better cosmetic results, and lower cost, than the CLA 3-port procedure because of the fewer number of ports.
Long-term results of 81 prevertebral subclavian artery angioplasties: a 26-year experience.
Berger, Ludovic; Bouziane, Zacharie; Felisaz, Aurélien; Coffin, Olivier; Dugue, Audrey; Maiza, Dominique
2011-11-01
Long-term results of transluminal angioplasty (TLA) of the prevertebral subclavian artery (PVSA) are not well known. The aim of this work was to present a retrospective analysis of a consecutive series of 81 TLAs of the PVSA, with a mean follow-up of approximately 7 years (82 months). From January 1984 to May 2007, 81 TLAs of PVSA were consecutively performed in 72 patients (64% men; median age = 56.7 years) to treat 71 tight stenoses and 10 occlusions. In 58 cases, TLA was carried out under local anesthesia (71.6%), 65 times by femoral approach, and 16 times by humeral approach. A percutaneous approach was used 72 times (89%). A stent was placed in 18 cases (22.2%). Immediate technical success rate was 93%. One transient monoplegia was noticed after TLA and four puncture complications were observed, which occurred significantly more frequently with percutaneous humeral approach (p = 0.024). A recurrent stenosis occurred 28 times (34.6%) and was symptomatic in three cases. With a mean 82-month follow-up (3-299 months), primary patency at 10 years was 85.2% and primary assisted patency was 92.6%. No restenosis occurred after the 25th month of the follow-up. No restenosis factor was statistically predictive. TLA of the PVSA is a mildly invasive and efficient treatment. Early restenoses are frequent but remain accessible to a new TLA with stable long-term results. Copyright © 2011 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.
Kwee, Sandi A; Lim, John; Watanabe, Alex; Kromer-Baker, Kathleen; Coel, Marc N
2014-06-01
This study investigated the prognostic significance of metabolically active tumor volume (MATV) measurements applied to (18)F-fluorocholine PET/CT in castration-resistant prostate cancer (CRPC). (18)F-fluorocholine PET/CT imaging was performed on 30 patients with CRPC. Metastatic disease was quantified on the basis of maximum standardized uptake value (SUV(max)), MATV, and total lesion activity (TLA = MATV × mean standardized uptake value). Tumor burden indices derived from whole-body summation of PET tumor volume measurements (i.e., net MATV and net TLA) were evaluated as variables in Cox regression and Kaplan-Meier survival analyses. Net MATV ranged from 0.12 cm(3) to 1,543.9 cm(3) (median, 52.6 cm(3)). Net TLA ranged from 0.40 to 6,688.7 g (median, 225.1 g). Prostate-specific antigen level at the time of PET correlated significantly with net MATV (Pearson r = 0.65, P = 0.0001) and net TLA (r = 0.60, P = 0.0005) but not highest lesional SUV(max) of each scan. Survivors were followed for a median 23 mo (range, 6-38 mo). On Cox regression analyses, overall survival had a significant association with net MATV (P = 0.0068), net TLA (P = 0.0072), and highest lesion SUV(max) (P = 0.0173) and a borderline association with prostate-specific antigen level (P = 0.0458). Only net MATV and net TLA remained significant in univariate-adjusted survival analyses. Kaplan-Meier analysis demonstrated significant differences in survival between groups stratified by median net MATV (log-rank P = 0.0371), net TLA (log-rank P = 0.0371), and highest lesion SUV(max) (log-rank P = 0.0223). Metastatic prostate cancer detected by (18)F-fluorocholine PET/CT can be quantified on the basis of volumetric measurements of tumor metabolic activity. The prognostic value of (18)F-fluorocholine PET/CT may stem from this capacity to assess whole-body tumor burden. With further clinical validation, (18)F-fluorocholine PET-based indices of global disease activity and mortality risk could prove useful in patient-individualized treatment of CRPC. © 2014 by the Society of Nuclear Medicine and Molecular Imaging, Inc.
Afilalo, Jonathan; Grapsa, Julia; Nihoyannopoulos, Petros; Beaudoin, Jonathan; Gibbs, J Simon R; Channick, Richard N; Langleben, David; Rudski, Lawrence G; Hua, Lanqi; Handschumacher, Mark D; Picard, Michael H; Levine, Robert A
2015-05-01
Tricuspid regurgitation (TR) is a risk factor for mortality in pulmonary hypertension (PH). TR severity varies among patients with comparable degrees of PH and right ventricular remodeling. The contribution of leaflet adaptation to the pathophysiology of TR has yet to be examined. We hypothesized that tricuspid leaflet area (TLA) is increased in PH, and that the adequacy of this increase relative to right ventricular remodeling determines TR severity. A prospective cohort of 255 patients with PH from pre and postcapillary pathogeneses was assembled from 2 centers. Patients underwent a 3-dimensional echocardiogram focused on the tricuspid apparatus. TLA was measured with the Omni 4D software package. Compared with normal controls, patients with PH had a 2-fold increase in right ventricular volumes, 62% increase in annular area, and 49% increase in TLA. Those with severe TR demonstrated inadequate increase in TLA relative to the closure area, such that the ratio of TLA:closure area <1.78 was highly predictive of severe TR (odds ratio, 68.7; 95% confidence interval, 16.2-292.7). The median vena contracta width was 8.5 mm in the group with small TLA and large closure area as opposed to 4.8 mm in the group with large TLA and large closure area. TLA plays a significant role in determining which patients with PH develop severe functional TR. The ratio of TLA:closure area, reflecting the balance between leaflet adaptation versus annular dilation and tethering forces, is an indicator of TR severity that may identify which patients stand to benefit from leaflet augmentation during tricuspid valve repair. © 2015 American Heart Association, Inc.
Pyo, Kyoung-Ho; Jung, Bong-Kwang; Xin, Chun-Feng; Lee, You-Won; Chai, Jong-Yil; Shin, Eun-Hee
2014-12-01
Toxoplasma gondii is an intracellular protozoan parasite that causes a Th1 cellular immunity. Our previous study showed that T. gondii lysate antigen (TLA) treatment in S180 tumor-bearing mice resulted in tumor reduction by suppressing CD31 expression, a marker of angiogenesis. In the present study, to investigate tumor suppressive effect of TLA under the absence of T lymphocytes, athymic nude mice were compared with euthymic mice in the anti-tumorigenic effect triggered by TLA in CT26 tumors. According to the results, intratumorally injected TLA reduced tumor growth and TIMP-1 level, a metastatic marker, in both euthymic and athymic mice. TLA treatment led to a sharp increase in IL-12 expression in serum cytokine profiling of athymic mice, and increased MyD88 signals in macrophages derived from the bone marrow, implying the activation of innate immunity. The selective induction of IL-12 by TLA treatment had an anti-tumorigenic effect.
Pyo, Kyoung-Ho; Jung, Bong-Kwang; Xin, Chun-Feng; Lee, You-Won; Chai, Jong-Yil
2014-01-01
Toxoplasma gondii is an intracellular protozoan parasite that causes a Th1 cellular immunity. Our previous study showed that T. gondii lysate antigen (TLA) treatment in S180 tumor-bearing mice resulted in tumor reduction by suppressing CD31 expression, a marker of angiogenesis. In the present study, to investigate tumor suppressive effect of TLA under the absence of T lymphocytes, athymic nude mice were compared with euthymic mice in the anti-tumorigenic effect triggered by TLA in CT26 tumors. According to the results, intratumorally injected TLA reduced tumor growth and TIMP-1 level, a metastatic marker, in both euthymic and athymic mice. TLA treatment led to a sharp increase in IL-12 expression in serum cytokine profiling of athymic mice, and increased MyD88 signals in macrophages derived from the bone marrow, implying the activation of innate immunity. The selective induction of IL-12 by TLA treatment had an anti-tumorigenic effect. PMID:25548411
A new Tla region antigen Qa-11, similar to Qa-2 and associated with B-type beta 2-microglobulin.
van de Meugheuvel, W; van Seventer, G; Demant, P
1985-04-01
A new antigen, Qa-11, is detected as a 40,000 dalton band in the SDS-PAGE of immunoprecipitates of radiolabeled lymphocyte membrane preparations. In C57BL H-2 congenic strains, its presence is controlled by a gene in the Tla region. In strains with genetic background other than C57BL it is not expressed. Tests with recombinant inbred strains and with H-3 congenic strains show that, in addition to the Tla region, a gene linked to or identical with the beta 2-microglobulin-b-allele is required for the expression of Qa-11 as well. The mobility of the Qa-11 antigen in SDS-PAGE and in isoelectrofocusing is the same as that of Qa-2 antigen. The Cleveland peptide maps of Qa-2 and Qa-11 are identical as well. This finding, that the Tla region controlled Qa-11 antigen is structurally very similar to the Qa-2 antigen, contrasts with the fact that Tla region products do not react with anti-Qa-2 sera. This paradox could be explained by a separate Qa-11 region between Qa-2 and Tla. Alternatively, it is possible that the Qa-11 antigen is the result of the action of a modifying gene in the Tla region upon a Qa-2 gene product, or that the structural gene for Qa-11 is located in the Qa-2 region and a Tla region gene controls its expression.
TLA — markers and nuclear scanning method for wear rate monitoring
NASA Astrophysics Data System (ADS)
Stan-Sion, C.; Plostinaru, D.; Ivan, A.; Ivanov, E.; Dudu, D.; Catana, M.; Roman, M.
1994-08-01
Two new extensions of the TLA-direct measuring method are presented: the TLA-markers for wear control and the nuclear scanning method for monitoring wear non-uniformity on large surfaces. Both methods were applied to measure the material loss on the surface of railway car brake disks.
Choice of threshold line angle for binary phase-only filters
NASA Astrophysics Data System (ADS)
Vijaya Kumar, Bhagavatula; Hendrix, Charles D.
1993-10-01
The choice of threshold line angle (TLA) is an important issue in designing Binary Phase-Only Filters (BPOFs). In this paper, we derive expressions that explicitly relate the TLA to correlation peak intensity. We also show some examples that illustrate the effect of choosing the wrong TLA.
Extraction of neptunium by trilaurylamine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Patil, S.K.; Swarup, R.; Ramaniah, M.V.
1972-07-01
Trilaurylamine (TLA) is considered as useful solvent for the final purification of plutonium and neptunium. As TLA is considered as an alternate possible extractant for the final purification of plutonium and neptunium at Tarapur Reprocessing Plant under construction, it was considered necessary to study the optimum conditions for the extraction of neptunium using TLA.
Terawaki, Hiroyuki; Nakayama, Masaaki; Seto, Kazuhiko; Yoshimura, Kazunobu; Hasegawa, Toshio
2004-08-01
We have established a new method of measuring translymphatic fluid absorption (TLA) using technetium-99m ((99m)Tc) human serum albumin diethylenetriamine pentaacetic acid ((99m)Tc-HSAD) that can be used commonly in clinical practice. This new method was applied in 13 continuous ambulatory peritoneal dialysis patients (11 males and two females) who had various peritoneal permeability and capacities for peritoneal transport of water. (99m)Tc-HSAD 740MBq was injected in 2 L of peritoneal dialysis fluid with 2.5% glucose, mixed well, and administered intraperitoneally. The fluid was drained extraperitoneally after 4 h and TLA was determined by the in vivo loss of (99m)Tc-HSAD. TLA was 1.41 +/- 1.11 mL/min (mean +/- SD; range, 0.27-3.69 mL/min). The estimated reduction rate by TLA in trans-peritoneally removed fluid ranged from 14.2 to 84.4%, indicating that TLA could have an extremely significant negative effect in some cases on total drainage volume. The present study, using new tracer (99m)Tc-HSAD, could confirm a large individual difference in TLA, indicating TLA as an important contributing factor for fluid-removal failure in continuous ambulatory peritoneal dialysis patients.
Neuropsychological and structural brain lesions in multiple sclerosis: a regional analysis.
Swirsky-Sacchetti, T; Mitchell, D R; Seward, J; Gonzales, C; Lublin, F; Knobler, R; Field, H L
1992-07-01
Quantified lesion scores derived from MRI correlate significantly with neuropsychological testing in patients with multiple sclerosis (MS). Variables used to reflect disease severity include total lesion area (TLA), ventricular-brain ratio, and size of the corpus callosum. We used these general measures of cerebral lesion involvement as well as specific ratings of lesion involvement by frontal, temporal, and parieto-occipital regions to quantify the topographic distribution of lesions and consequent effects upon cognitive function. Lesions were heavily distributed in the parieto-occipital regions bilaterally. Neuropsychological tests were highly related to all generalized measures of cerebral involvement, with TLA being the best predictor of neuropsychological deficit. Mean TLA for the cognitively impaired group was 28.30 cm2 versus 7.41 cm2 for the cognitively intact group (p less than 0.0001). Multiple regression analyses revealed that left frontal lobe involvement best predicted impaired abstract problem solving, memory, and word fluency. Left parieto-occipital lesion involvement best predicted deficits in verbal learning and complex visual-integrative skills. Analysis of regional cerebral lesion load may assist in understanding the particular pattern and course of cognitive deficits in MS.
Jin, Wanchun; Yamaguchi, Yoshihiro; Kimura, Kouji; Kumar, Anupriya; Yamada, Mototsugu; Morinaka, Akihiro; Sakamaki, Yoshiaki; Yonezawa, Minoru; Kurosaki, Hiromasa; Arakawa, Yoshichika
2017-01-01
ABSTRACT The development of effective inhibitors that block extended-spectrum β-lactamases (ESBLs) and restore the action of β-lactams represents an effective strategy against ESBL-producing Enterobacteriaceae. We evaluated the inhibitory effects of the diazabicyclooctanes avibactam and OP0595 against TLA-3, an ESBL that we identified previously. Avibactam and OP0595 inhibited TLA-3 with apparent inhibitor constants (Ki app) of 1.71 ± 0.10 and 1.49 ± 0.05 μM, respectively, and could restore susceptibility to cephalosporins in the TLA-3-producing Escherichia coli strain. The value of the second-order acylation rate constant (k2/K, where k2 is the acylation rate constant and K is the equilibrium constant) of avibactam [(3.25 ± 0.03) × 103 M−1 · s−1] was closer to that of class C and D β-lactamases (k2/K, <104 M−1 · s−1) than that of class A β-lactamases (k2/K, >104 M−1 · s−1). In addition, we determined the structure of TLA-3 and that of TLA-3 complexed with avibactam or OP0595 at resolutions of 1.6, 1.6, and 2.0 Å, respectively. TLA-3 contains an inverted Ω loop and an extended loop between the β5 and β6 strands (insertion after Ser237), which appear only in PER-type class A β-lactamases. These structures might favor the accommodation of cephalosporins harboring bulky R1 side chains. TLA-3 presented a high catalytic efficiency (kcat/Km) against cephalosporins, including cephalothin, cefuroxime, and cefotaxime. Avibactam and OP0595 bound covalently to TLA-3 via the Ser70 residue and made contacts with residues Ser130, Thr235, and Ser237, which are conserved in ESBLs. Additionally, the sulfate group of the inhibitors formed polar contacts with amino acid residues in a positively charged pocket of TLA-3. Our findings provide a structural template for designing improved diazabicyclooctane-based inhibitors that are effective against ESBL-producing Enterobacteriaceae. PMID:28739781
Jin, Wanchun; Wachino, Jun-Ichi; Yamaguchi, Yoshihiro; Kimura, Kouji; Kumar, Anupriya; Yamada, Mototsugu; Morinaka, Akihiro; Sakamaki, Yoshiaki; Yonezawa, Minoru; Kurosaki, Hiromasa; Arakawa, Yoshichika
2017-10-01
The development of effective inhibitors that block extended-spectrum β-lactamases (ESBLs) and restore the action of β-lactams represents an effective strategy against ESBL-producing Enterobacteriaceae We evaluated the inhibitory effects of the diazabicyclooctanes avibactam and OP0595 against TLA-3, an ESBL that we identified previously. Avibactam and OP0595 inhibited TLA-3 with apparent inhibitor constants ( K i app ) of 1.71 ± 0.10 and 1.49 ± 0.05 μM, respectively, and could restore susceptibility to cephalosporins in the TLA-3-producing Escherichia coli strain. The value of the second-order acylation rate constant ( k 2 / K , where k 2 is the acylation rate constant and K is the equilibrium constant) of avibactam [(3.25 ± 0.03) × 10 3 M -1 · s -1 ] was closer to that of class C and D β-lactamases ( k 2 / K , <10 4 M -1 · s -1 ) than that of class A β-lactamases ( k 2 / K , >10 4 M -1 · s -1 ). In addition, we determined the structure of TLA-3 and that of TLA-3 complexed with avibactam or OP0595 at resolutions of 1.6, 1.6, and 2.0 Å, respectively. TLA-3 contains an inverted Ω loop and an extended loop between the β5 and β6 strands (insertion after Ser237), which appear only in PER-type class A β-lactamases. These structures might favor the accommodation of cephalosporins harboring bulky R1 side chains. TLA-3 presented a high catalytic efficiency ( k cat / K m ) against cephalosporins, including cephalothin, cefuroxime, and cefotaxime. Avibactam and OP0595 bound covalently to TLA-3 via the Ser70 residue and made contacts with residues Ser130, Thr235, and Ser237, which are conserved in ESBLs. Additionally, the sulfate group of the inhibitors formed polar contacts with amino acid residues in a positively charged pocket of TLA-3. Our findings provide a structural template for designing improved diazabicyclooctane-based inhibitors that are effective against ESBL-producing Enterobacteriaceae . Copyright © 2017 American Society for Microbiology.
Stoffels, I; Dissemond, J; Schulz, A; Hillen, U; Schadendorf, D; Klode, J
2012-02-01
Complete lymph node dissection (CLND) in melanoma patients with a positive sentinel lymph node (SLN) is currently being debated, as it is a cost-intensive surgical intervention with potentially high morbidity. This clinical study seeks to clarify the effectiveness, reliability and cost-effectiveness of CLND performed under tumescent local anaesthesia (TLA) compared with procedures under general anaesthesia (GA). We retrospectively analysed the data from 60 patients with primary malignant melanoma American Joint Committee on Cancer stage III who underwent CLND. Altogether 26 (43.3%) patients underwent CLND under TLA and 34 (56.7%) patients underwent CLND under GA. Fifteen of 43 (34.9%) patients had a complication, such as development of seromas and/or wound infections. The rate of complications was 25.0% (3/12) in the axilla subgroup and 28.6% (4/14) in the groin subgroup of the TLA group. In the GA group, the complication rate was 31.3% (5/16) in the axilla subgroup and 44.4% (8/18) in the groin subgroup. The costs for CLND were significantly less for the CLND in a procedure room performed under TLA (mean €67.26) compared with CLND in an operating room under GA (mean €676.20, P < 0.0001). In conclusion, this study confirms that TLA is an excellent, safe, effective and cost-efficient alternative to GA for CLND in melanoma patients. © 2011 The Authors. Journal of the European Academy of Dermatology and Venereology © 2011 European Academy of Dermatology and Venereology.
Wagner, Angelika; Schabussova, Irma; Ruttkowski, Bärbel; Peschke, Roman; Kur, Józef; Kundi, Michael; Joachim, Anja; Wiedermann, Ursula
2015-01-01
Infection with the ubiquitous parasite Toxoplasma gondii is a threat for immunocompromised patients and pregnant women and effective immune-prophylaxis is still lacking. Here we tested a mixture of recombinant T. gondii antigens expressed in different developmental stages, i.e., SAG1, MAG1 and GRA7 (SMG), and a lysate derived from T. gondii tachyzoites (TLA) for prophylactic vaccination against cyst formation. Both vaccine formulations were applied systemically followed by an oral TLA-booster in BALB/c mice. Systemic priming with SMG and oral TLA-booster did not show significant induction of protective immune responses. In contrast, systemic priming and oral booster with TLA induced higher levels of Toxoplasma-specific IgG, IgG1 and IgG2a in sera as well as high levels of Toxoplasma-specific IgG1 in small intestines. Furthermore, high levels of Toxoplasma-specific Th1-, Th17- and Th2-associated cytokines were only detected in restimulated splenocytes of TLA-vaccinated mice. Importantly, in mice orally infected with T. gondii oocysts, only TLA-vaccination and booster reduced brain cysts. Furthermore, sera from these mice reduced tachyzoites invasion of Vero cells in vitro, indicating that antibodies may play a critical role for protection against Toxoplasma infection. Additionally, supernatants from splenocyte cultures of TLA-vaccinated mice containing high levels of IFN-γ lead to substantial production of nitric oxide (NO) after incubation with macrophages in vitro. Since NO is involved in the control of parasite growth, the high levels of IFN-γ induced by vaccination with TLA may contribute to the protection against T. gondii. In conclusion, our data indicate that prime-boost approach with TLA, but not with the mixture of recombinant antigens SMG, induces effective humoral and cellular Toxoplasma-specific responses and leads to significant reduction of cerebral cysts, thereby presenting a viable strategy for further vaccine development against T. gondii infection.
Teacher Language Awareness and the Professional Knowledge Base of the L2 Teacher
ERIC Educational Resources Information Center
Andrews, Stephen
2003-01-01
This paper provides an introduction to teacher language awareness (TLA) and a personal reconceptualisation of the relationship between TLA and other dimensions of teacher knowledge, revisiting issues discussed in Andrews (2001). In the first part of the paper, knowledge of subject matter is identified as the core of TLA. Given the increased…
Bilateral temporal lobe volume reduction parallels cognitive impairment in progressive aphasia.
Andersen, C; Dahl, C; Almkvist, O; Ostberg, P; Julin, P; Wahlund, L O
1997-10-01
Patients with isolated aphasia in the absence of other cognitive abnormalities have been the focus of several studies during the past decade. It has been called primary progressive aphasia (PPA), and the typical features of this syndrome are marked atrophy of the left temporal lobe according to the radiological examination and a language disorder as the initial symptom. In previous studies of PPA, the selection of the patients was based mainly on linguistic symptoms. Now, when computed tomography or magnetic resonance imaging scans are part of the routine investigation of cognitive impairment and suspected dementia, the patients with lobar atrophy will be found at an earlier stage. In the present study, we used a new approach and defined the study group by selecting patients with obvious left temporal lobe atrophy, assessed by MRI, and we referred to them as patients with temporal lobe atrophy (TLA). To identify the features that distinguish TLA from other primary neurodegenerative disorders. Six patients with TLA were compared with patients with Alzheimer disease (AD), patients with frontal lobe dementia (FLD), and healthy control subjects. The investigations included magnetic resonance imaging volumetry, single photon emission computed tomography, and neuropsychologic and linguistic evaluations. In the TLA group, the mean volume of the left temporal lobe was 35% smaller than the right, while in the AD and FLD groups, the atrophy was symmetrical and bilateral. In the TLA group, the absolute volumes of the temporal lobes were significantly smaller on the left side compared with the AD and FLD groups, whereas there was no difference on the right side. The cerebral blood flow pattern in TLA was asymmetric and differed from that in the other study groups. All patients with TLA had a history of progressive Wernicke-type aphasia, ranging from 2 to 6 years. They showed primary verbal memory impairment but had preserved visuospatial functions. The clinical condition of all patients with TLA deteriorated during the study period; severe aphasia developed, and the patients exhibited signs of frontal lobe dysfunction. Serial volumetric measurements in 4 of 6 patients showed an annual 8% to 9% decrease of both left and right temporal lobes. The initial marked asymmetry in cognitive function found in patients with TLA contrasts with the general decline found in patients with AD. The bilateral degenerative process evident in patients with TLA paralleled the clinical deterioration, indicating TLA to be a non-AD lobar atrophy that develops into generalized cognitive dysfunction and dementia.
Jabeen, Nazish; Malik, Sajid
2015-01-01
Objective: Traumatic limb amputations (TLA) are structural defects that cause mild-to-severe disabilities and have significant impact on the quality of life of subjects. A recent epidemiological study in Bhimber District, AJK, Pakistan, revealed that TLA had a very high incidence among the young/adult females. The present study aimed at determining the prevalence, pattern, causes and risk factors associated with TLA in that female sample. Methods: In a prospective door-to-door survey, 1731 females were randomly enrolled, and clinico-etiological investigations on 19 subjects with TLA were carried out in a follow-up study. Affected subjects were physically examined and phenotypic detail and restriction to normal function were documented. Results: There were 19 subjects with TLA, hence the prevalence was estimated to be 10.98/1,000 (0.011%; CI=0.0061-0.0159). TLA mostly involved the upper limbs and right hand. Transphalangeal amputations were most frequent, followed by involvements of middle/upper arm and leg segments. These analyses further revealed that agriculture tools were the leading cause of trauma. TLA were witnessed to be higher in subjects originating from Samahni tehsil (OR:2.71), rural areas (OR:3.33), those who were illiterate (OR:2.65), married, spoke Pahari language (OR:1.73), those who fall in higher age category (OR:16.74), and had certain professions. Conclusion: Limb amputations had heavy bearings on the lives of subjects. Curiously, majority of these traumas could be avoided by adopting certain safety measures. Prevalence and risk estimate of TLA across various socio-demographic variables of Bhimber population would be useful in guiding further studies and the public health policy to mitigate the impact of these anomalies. PMID:25878614
Jabeen, Nazish; Malik, Sajid
2015-01-01
Traumatic limb amputations (TLA) are structural defects that cause mild-to-severe disabilities and have significant impact on the quality of life of subjects. A recent epidemiological study in Bhimber District, AJK, Pakistan, revealed that TLA had a very high incidence among the young/adult females. The present study aimed at determining the prevalence, pattern, causes and risk factors associated with TLA in that female sample. In a prospective door-to-door survey, 1731 females were randomly enrolled, and clinico-etiological investigations on 19 subjects with TLA were carried out in a follow-up study. Affected subjects were physically examined and phenotypic detail and restriction to normal function were documented. There were 19 subjects with TLA, hence the prevalence was estimated to be 10.98/1,000 (0.011%; CI=0.0061-0.0159). TLA mostly involved the upper limbs and right hand. Transphalangeal amputations were most frequent, followed by involvements of middle/upper arm and leg segments. These analyses further revealed that agriculture tools were the leading cause of trauma. TLA were witnessed to be higher in subjects originating from Samahni tehsil (OR:2.71), rural areas (OR:3.33), those who were illiterate (OR:2.65), married, spoke Pahari language (OR:1.73), those who fall in higher age category (OR:16.74), and had certain professions. Limb amputations had heavy bearings on the lives of subjects. Curiously, majority of these traumas could be avoided by adopting certain safety measures. Prevalence and risk estimate of TLA across various socio-demographic variables of Bhimber population would be useful in guiding further studies and the public health policy to mitigate the impact of these anomalies.
Miler, Marijana; Nikolac Gabaj, Nora; Dukic, Lora; Simundic, Ana-Maria
2017-12-27
The aim of the study was to estimate improvement of work efficiency in the laboratory after implementation of total laboratory automation (TLA) by Abbott Accelerator a3600 in the laboratory with measuring different key performance indicators (KPIs) before and after TLA implementation. The objective was also to recommend steps for defining KPIs in other laboratories. For evaluation of improvement 10 organizational and/or technical KPIs were defined for all phases of laboratory work and measured before (November 2013) and after (from 2015 to 2017) TLA implementation. Out of 10 defined KPIs, 9 were successfully measured and significantly improved. Waiting time for registration of samples in the LIS was significantly reduced from 16 (9-28) to 9 (6-16) minutes after TLA (P < 0.001). After TLA all tests were performed at core biochemistry analyzers which significantly reduced walking distance for sample management (for more than 800 m per worker) and number of tube touches (for almost 50%). Analyzers downtime and engagement time for analyzers maintenance was reduced for 50 h and 28 h per month, respectively. TLA eliminated manual dilution of samples with extreme results with sigma values increment from 3.4 to >6 after TLA. Although median turnaround time TAT for potassium and troponin was higher (for approximately 20 min), number of outliers with TAT >60 min expressed as sigma values were satisfying (>3). Implementation of the TLA improved the most of the processes in our laboratory with 9 out of 10 properly defined and measured KPIs. With proper planning and defining of KPIs, every laboratory could measure changes in daily workflow.
Anti-colorectal cancer effects of tripolinolate A from Tripolium vulgare.
Chen, Lu; Wang, Wen-Ling; Song, Teng-Fei; Xie, Xin; Ye, Xue-Wei; Liang, Ying; Huang, Hao-Cai; Yan, Shi-Lun; Lian, Xiao-Yuan; Zhang, Zhi-Zhen
2017-08-01
Tripolinolate A (TLA) is recently identified as a new compound from a halophyte plant Tripolium vulgare and has been shown to have significant in vitro activity against the proliferation of colorectal cancer and glioma cells. This study was designed to further investigate the effects of TLA on the proliferation of human normal cells, and the apoptosis and cell cycle in colorectal cancer cells, and the growth of tumors in the colorectal cancer-bearing animals. The data obtained from this study demonstrated that: 1) TLA had much less cytotoxicity in the human normal cells than the colorectal cancer cells; 2) TLA remarkably induced apoptosis in the human colorectal cancer cells and blocked cell cycle at G 2 /M phase, and 3) TLA had significant anti-colorectal cancer activity in the tumor-bearing animals. Copyright © 2017 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.
Clinical and quantitative analysis of patients with crowned dens syndrome.
Takahashi, Teruyuki; Tamura, Masato; Takasu, Toshiaki; Kamei, Satoshi
2017-05-15
Crowned dens syndrome (CDS) is a radioclinical entity defined by calcium deposition on the transverse ligament of atlas (TLA). In this study, the novel semi-quantitative diagnostic criteria for CDS to evaluate the degree of calcification on TLA by cervical CT are proposed. From January 2010 to September 2014, 35 patients who were diagnosed with CDS by cervical CT were adopted as subjects in this study. Based on novel criteria, calcium deposition on TLA was classified into "Stage" and "Grade", to make a score, which was evaluated semi-quantitatively. The correlation between calcification score and CRP level or pain score, and the effects of treatments, such as NSAIDs and corticosteroids, were statistically analyzed. The total calcification score from added "Stage" and "Grade" scores demonstrated a significantly strong and linear correlation with CRP level (R 2 =0.823, **p<0.01). In the multiple comparison test for the treatment effects, significant improvement of the CRP level and pain score were demonstrated after corticosteroid therapy (**p<0.01) compared with NSAIDs. In the conditional logistic regression analysis, the rapid end of corticosteroid therapy was an independent risk factor for relapse of cervico-occipital pain [OR=50.761, *p=0.0419]. The degree of calcification on TLA evaluated by the novel semi-quantitative criteria significantly correlated with CRP level. In the treatment of CDS, it is recommended that a low dosage (15-30mg) of corticosteroids be used as first-line drugs rather than conventional NSAID therapy. Additionally, it is also recommended to gradually decrease the dosage of corticosteroids. Copyright © 2017 Elsevier B.V. All rights reserved.
Sociocultural Perspectives on Teacher Language Awareness in Form-Focused EFL Classroom Instruction
ERIC Educational Resources Information Center
Luk, Jasmine C. M.; Wong, Ruth M. H.
2010-01-01
A teacher's language awareness (TLA) is generally believed to have a significant impact on grammar or form-focused (FonF) instruction. TLA has traditionally been assumed to be a cognitive construct. A more recent view on TLA argues for its sociocultural significance in second language learning. This paper builds on this recent view and attempts to…
Electrochemotherapy under tumescent local anesthesia for the treatment of cutaneous metastases.
Kendler, Michael; Micheluzzi, Martin; Wetzig, Tino; Simon, Jan C
2013-07-01
The surgical management of cutaneous metastasis (CM) is challenging, particularly in elderly patients, in whom general anesthesia can be difficult because of comorbidity. To test the effectiveness of tumescent local anesthesia (TLA) to achieve adequate anesthesia during the treatment of extensive CM with electrochemotherapy (ECT), previously only performed under general anesthesia. We conducted five ECT treatments of CM with intralesional bleomycin under TLA. We examined pain scores before, during, and after treatment; analgesic use; and side effects. The intention of the treatment was palliative in all cases. We treated four patients (ages 75-88) with CM with a mean area of 126 cm(2) (range 12-198 cm(2) ) with 356 mL of TLA per treatment (range 180-450 mL). The ECT treatment under TLA demonstrated that anesthesia was adequate, with moderate pain during and slight pain after the procedure as measured on a visual analog scale (VAS). In this proof-of-principle study, we demonstrated that ECT can be performed under TLA; TLA might be a useful new anesthesia option for patients treated with ECT. © 2013 by the American Society for Dermatologic Surgery, Inc. Published by Wiley Periodicals, Inc.
Robledo, J A; Mejía, G I; Morcillo, N; Chacón, L; Camacho, M; Luna, J; Zurita, J; Bodon, A; Velasco, M; Palomino, J C; Martin, A; Portaels, F
2006-06-01
Tuberculosis (TB) diagnostic laboratories in Latin America. Evaluation of thin-layer agar (TLA) compared to Löwenstein-Jensen (LJ) culture for the diagnosis of TB. Phase II prospective study in six laboratories. Samples included sputum and extra-pulmonary specimens from patients with a clinical diagnosis of TB. Respiratory samples were decontaminated using NaOH/ NALC; all samples were centrifuged, stained with Ziehl-Neelsen for acid-fast bacilli (AFB), cultured on LJ and TLA and identified according to recommended procedures. Sensitivity and likelihood ratios (LR), growth detection time and contamination rate were calculated for both media. A total of 1118 clinical specimens were studied. Cultures detected Mycobacterium tuberculosis in all AFB-positive samples, whereas for AFB-negative specimens LJ detected 3.2% and TLA 4.4%. Sensitivity was 92.6% (95%CI 87.9-95.9) and 84.7% (95%CI 78.8-89.0) for TLA and LJ, respectively. Positive and negative LRs were similar. Contamination was 5.1% for TLA and 3.0% for LJ. Median time to detection of a positive culture was 11.5 days (95%CI 9.3-15.0) for TLA and 30.5 days (95%CI 26.9-39.0) for LJ (P < 0.0001). Difference in the characteristics of the participating laboratories, the disease prevalence and the number and type of specimens processed did not affect the overall performance of TLA as compared to LJ, supporting the robustness of the method and its feasibility in different laboratory settings.
Wagner, Angelika; Schabussova, Irma; Ruttkowski, Bärbel; Peschke, Roman; Kur, Józef; Kundi, Michael; Joachim, Anja; Wiedermann, Ursula
2015-01-01
Introduction Infection with the ubiquitous parasite Toxoplasma gondii is a threat for immunocompromised patients and pregnant women and effective immune-prophylaxis is still lacking. Methods Here we tested a mixture of recombinant T. gondii antigens expressed in different developmental stages, i.e., SAG1, MAG1 and GRA7 (SMG), and a lysate derived from T. gondii tachyzoites (TLA) for prophylactic vaccination against cyst formation. Both vaccine formulations were applied systemically followed by an oral TLA-booster in BALB/c mice. Results Systemic priming with SMG and oral TLA-booster did not show significant induction of protective immune responses. In contrast, systemic priming and oral booster with TLA induced higher levels of Toxoplasma-specific IgG, IgG1 and IgG2a in sera as well as high levels of Toxoplasma-specific IgG1 in small intestines. Furthermore, high levels of Toxoplasma-specific Th1-, Th17- and Th2-associated cytokines were only detected in restimulated splenocytes of TLA-vaccinated mice. Importantly, in mice orally infected with T. gondii oocysts, only TLA-vaccination and booster reduced brain cysts. Furthermore, sera from these mice reduced tachyzoites invasion of Vero cells in vitro, indicating that antibodies may play a critical role for protection against Toxoplasma infection. Additionally, supernatants from splenocyte cultures of TLA-vaccinated mice containing high levels of IFN-γ lead to substantial production of nitric oxide (NO) after incubation with macrophages in vitro. Since NO is involved in the control of parasite growth, the high levels of IFN-γ induced by vaccination with TLA may contribute to the protection against T. gondii. Conclusion In conclusion, our data indicate that prime-boost approach with TLA, but not with the mixture of recombinant antigens SMG, induces effective humoral and cellular Toxoplasma-specific responses and leads to significant reduction of cerebral cysts, thereby presenting a viable strategy for further vaccine development against T. gondii infection. PMID:26010355
NASA Astrophysics Data System (ADS)
Chowdhury, D. P.; Guin, R.; Saha, S. K.; Sudersanan, M.
2003-11-01
Experimental cross sections of a number of reaction channels of 16O ion induced reactions on natural copper target have been determined at different energies in the range of 50-110 MeV of 16O projectile by stacked foil activation technique. The cross sections have been compared with theoretical calculations using the computer code ALICE-91. The experimental values compared reasonably well with the corresponding theoretical estimates. The results indicate no significant role of incomplete fusion process in the 16O induced reactions on natural copper in the energy range of ⩽7 MeV/nucleon. As heavy ion beam produces an extremely narrow layer of activities in the surface of a material, these reactions could be useful for thin layer activation (TLA) study. The purpose of this work is to apply heavy ion activation in TLA technique for the study of surface wear with increased sensitivity.
A nuclear method to measure spallation by thermal cycling of protective surface layers
NASA Astrophysics Data System (ADS)
Stroosnijder, M. F.; Macchi, G.
1995-05-01
After a general introduction on spallation by thermal cycling, the principle of Thin Layer Activation (TLA) is outlined. A practical setup to measure spallation of protective surface layers by thermal cycling using TLA is discussed. Its use is illustrated with the study of the spallation behaviour of an advanced thermal barrier coating. It is shown that among the various benefits, TLA has a direct relation to material loss and shows a significant increase in sensitivity over other test methods. Due to its intrinsic properties, TLA can contribute to a greater scientific understanding of material degradation by thermal cycling and it can provide a more reliable assessment of the service lives of technical components.
NASA Astrophysics Data System (ADS)
Chowdhury, D. P.; Pal, Sujit; Parthasarathy, R.; Mathur, P. K.; Kohli, A. K.; Limaye, P. K.
1998-09-01
Thin layer activation (TLA) technique has been developed in Zr based alloy materials, e.g., zircaloy II, using 40 MeV α-particles from Variable Energy Cyclotron Centre at Calcutta. A brief description of the methodology of TLA technique is presented to determine the surface wear. The sensitivity of the measurement of surface wear in zircaloy material is found to be 0.22±0.05 μm. The surface wear is determined by TLA technique in zircaloy material which is used in pressurised heavy water reactor and the values have been compared with that obtained by conventional technique for the analytical validation of the TLA technique.
Minion, Jessica; Leung, Erika; Menzies, Dick; Pai, Madhukar
2010-10-01
Simple, rapid, and affordable tests are needed to detect drug resistance in Mycobacterium tuberculosis. We did a systematic review and meta-analysis to investigate the accuracy of microscopic-observation drug susceptibility (MODS) and thin layer agar (TLA) assays for rapid screening of patients at risk of drug-resistant tuberculosis. In accordance with protocols and methods recommended by the Cochrane Diagnostic Test Accuracy Working Group, we systematically searched PubMed, Embase, and Biosis for reports published between January, 1990, and February, 2009. We included studies investigating detection of drug resistance in M tuberculosis with the MODS or TLA assay, and in which an accepted reference standard was used. Data extracted from the studies were combined by use of bivariate random-effects regression models and hierarchical summary receiver operating characteristic curves to estimate sensitivity and specificity for detection of resistance to specific drugs. We identified 12 studies, of which nine investigated the MODS assay and three investigated the TLA assay. For the MODS assay of rifampicin resistance, pooled estimates were 98·0% (95% CI 94·5-99·3) for sensitivity and 99·4% (95·7-99·9) for specificity. For the MODS assay of isoniazid resistance with a 0·1 μg/mL cutoff, pooled sensitivity was 97·7% (94·4-99·1) and pooled specificity was 95·8% (88·1-98·6), but with a 0·4 μg/mL cutoff, sensitivity decreased to 90·0% (84·5-93·7) and specificity increased to 98·6% (96·9-99·4). All assessments of rifampicin and isoniazid resistance with the TLA assay yielded 100% accuracy. Mean turnaround time was 9·9 days (95% CI 4·1-15·8) for the MODS assay and 11·1 days (10·1-12·0) for the TLA assay. MODS and TLA assays are inexpensive, rapid alternatives to conventional methods for drug susceptibility testing of M tuberculosis. Our data and expert opinion informed WHO's recommendation for use of selected non-commercial drug susceptibility tests, including MODS, as an interim solution until capacity for genotypic or automated liquid culture drug susceptibility testing is developed. Stop TB Department of WHO. Copyright © 2010 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dennis Schmitt; Daniel Olsen
2005-09-30
Three methods were utilized to analyze key components of slow-speed, large-bore, natural gas integral engines. These three methods included the application of computational fluid dynamics (CFD), dynamic modal analysis using finite element analysis (FEA), and a stress analysis method also using FEA. The CFD analysis focuses primarily on the fuel mixing in the combustion chamber of a TLA engine. Results indicate a significant increase in the homogeneity of the air and fuel using high-pressure fuel injection (HPFI) instead of standard low-pressure mechanical gas admission valve (MGAV). A modal analysis of three engine crankshafts (TLA-6, HBA-6, and GMV-10) is developed andmore » presented. Results indicate that each crankshaft has a natural frequency and corresponding speed that is well away from the typical engine operating speed. A frame stress analysis method is also developed and presented. Two different crankcases are examined. A TLA-6 crankcase is modeled and a stress analysis is performed. The method of dynamic load determination, model setup, and the results from the stress analysis are discussed. Preliminary results indicate a 10%-15% maximum increase in frame stress due to a 20% increase in HP. However, the high stress regions were localized. A new hydraulically actuated mechanical fuel valve is also developed and presented. This valve provides equivalent high-energy (supersonic) fuel injection comparable to a HPFI system, at 1/5th of the natural gas fuel pressure. This valve was developed in cooperation with the Dresser-Rand Corporation.« less
Mundorf, Thomas K; Ogawa, Takahiro; Inui, Noritsugu; Naka, Hiroaki; Novack, Gary D; Crockett, R Stephens
2005-03-01
A new formulation of timolol with sorbic acid, timolol-LA (TLA) (Istaloldagger), has been developed which increases its ocular bioavailability. In the present study, we desired to evaluate the ocular comfort and systemic bioavailability of TLA in healthy volunteers in comparison to standard timolol maleate ophthalmic solution (TIM). This study was a randomized, double-masked, active-controlled, crossover evaluation of 0.5% TLA and 0.5% TIM, bid, in 12 normal healthy volunteers. Visits were at Days 0, 1, 2, 4 and 8 in each period, and there was a minimum 7 day interperiod washout. At all three post-dosing evaluation times (Day 1: Peak, Day 8: Trough, and Day 8: Peak), the 95% confidence interval for the difference between TLA and TIM was not more than 0.37 ng/mL. After administration of TLA, there was a greater incidence of burning/stinging and tearing, but not foreign body sensation, relative to TIM. In general, most symptoms were mild in intensity, and no subject discontinued treatment due to ocular discomfort. Both treatments decreased IOP to a similar level. TLA was relatively comfortable, with a safety profile consistent with further clinical development, and, with bid dosing (exaggerated [2X] that anticipated for clinical use), had a systemic bioavailability similar to that of TIM 0.5%, bid. The incidence of burning and stinging was higher with TLA than with TIM, although reports were mild in severity and did not result in any patient discontin uations. Although the results are of interest, further evaluation in a larger trial may be warranted.
Schauer, Uwe; Bergmann, Karl-Christian; Gerstlauer, Michael; Lehmann, Sylvia; Gappa, Monika; Brenneken, Amelie; Schulz, Christian; Ahrens, Peter; Schreiber, Jens; Wittmann, Michael; Hamelmann, Eckard
2015-01-01
Introduction Continuous or episodic allergen exposure is a major risk factor of frequent symptoms and exacerbations for patients with allergic asthma. It has been shown that temperature-controlled laminar airflow (TLA) significantly reduced allergen exposure and airway inflammation and improved quality of life of patients with poorly controlled allergic asthma. Objective The objective was to evaluate the effects of nighttime TLA when used during real-life conditions for 12 consecutive months in addition to the patients’ regular medication. Methods This multicenter, pre- and postretrospective observational study included patients with inadequately controlled moderate-to-severe allergic asthma who received add-on treatment with TLA for 12 consecutive months. Data on medication use, asthma control, asthma symptoms, lung function, use of hospital resources, and exacerbations were collected after 4 and 12 months and compared with corresponding data collected retrospectively from medical records during the year prior to inclusion in the study. Results Data from 30 patients (mean age 28; range 8–70) completing 4 months and 27 patients completing 12 months of TLA use are presented. The mean number of exacerbations was reduced from 3.6 to 1.3 (p<0.0001), and the ratio of asthma-related emergency room visits or hospitalizations diminished from 72.4 to 23.3% (p=0.001) or from 44.8 to 20.0% (p<0.05), respectively, after 12 months of TLA use. The Asthma Control Test index increased from 14.1 to 18.5 (p<0.0001). After 4 months of TLA use, clear improvements can be shown for most variables in line with the data collected after 12 months. Conclusions The addition of TLA to the patients’ regular medication significantly reduced exacerbations, asthma symptoms, and the utilization of hospital resources. The data support that TLA may be an important new non-pharmacological approach in the management of poorly controlled allergic asthma. PMID:26557252
Schauer, Uwe; Bergmann, Karl-Christian; Gerstlauer, Michael; Lehmann, Sylvia; Gappa, Monika; Brenneken, Amelie; Schulz, Christian; Ahrens, Peter; Schreiber, Jens; Wittmann, Michael; Hamelmann, Eckard
2015-01-01
Continuous or episodic allergen exposure is a major risk factor of frequent symptoms and exacerbations for patients with allergic asthma. It has been shown that temperature-controlled laminar airflow (TLA) significantly reduced allergen exposure and airway inflammation and improved quality of life of patients with poorly controlled allergic asthma. The objective was to evaluate the effects of nighttime TLA when used during real-life conditions for 12 consecutive months in addition to the patients' regular medication. This multicenter, pre- and postretrospective observational study included patients with inadequately controlled moderate-to-severe allergic asthma who received add-on treatment with TLA for 12 consecutive months. Data on medication use, asthma control, asthma symptoms, lung function, use of hospital resources, and exacerbations were collected after 4 and 12 months and compared with corresponding data collected retrospectively from medical records during the year prior to inclusion in the study. Data from 30 patients (mean age 28; range 8-70) completing 4 months and 27 patients completing 12 months of TLA use are presented. The mean number of exacerbations was reduced from 3.6 to 1.3 (p<0.0001), and the ratio of asthma-related emergency room visits or hospitalizations diminished from 72.4 to 23.3% (p=0.001) or from 44.8 to 20.0% (p<0.05), respectively, after 12 months of TLA use. The Asthma Control Test index increased from 14.1 to 18.5 (p<0.0001). After 4 months of TLA use, clear improvements can be shown for most variables in line with the data collected after 12 months. The addition of TLA to the patients' regular medication significantly reduced exacerbations, asthma symptoms, and the utilization of hospital resources. The data support that TLA may be an important new non-pharmacological approach in the management of poorly controlled allergic asthma.
Validity of the two-level approximation in the interaction of few-cycle light pulses with atoms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cheng Jing; Zhou Jianying
2003-04-01
The validity of the two-level approximation (TLA) in the interaction of atoms with few-cycle light pulses is studied by investigating a simple (V)-type three-level atom model. Even the transition frequency between the ground state and the third level is far away from the spectrum of the pulse; this additional transition can make the TLA inaccuracy. For a sufficiently large transition frequency or a weak coupling between the ground state and the third level, the TLA is a reasonable approximation and can be used safely. When decreasing the pulse width or increasing the pulse area, the TLA will give rise tomore » non-negligible errors compared with the precise results.« less
Validity of the two-level approximation in the interaction of few-cycle light pulses with atoms
NASA Astrophysics Data System (ADS)
Cheng, Jing; Zhou, Jianying
2003-04-01
The validity of the two-level approximation (TLA) in the interaction of atoms with few-cycle light pulses is studied by investigating a simple
Ion beam activation for materials analysis: Methods and application
DOE Office of Scientific and Technical Information (OSTI.GOV)
Conlon, T.W.
1981-04-01
A number of ion beam methods for materials analysis have been developed using Harwell's high voltage accelerators and these are currently being exploited for applications 'in house' and in industry. Ion beam activation is a relatively new area which has exhibited exceptional growth over the last few years. Activation by ion beams to produce a single dominant radioisotope as a surface label (thin layer activation or TLA) is becoming a mature technology offering ever increasing sensitivity for surface loss measurement (currently better than 0.1 ..mu..m or 10/sup -7/ cm/sup 3/ depending on the method of measurement) and remote monitoring ofmore » inaccessible components during studies of wear/erosion/ corrosion/sputtering and the like. With the increasingly established credibility of the method has come the realisation that: (i) more complex and even multiple activation profiles can be used to extract more information on the characteristics of the surface loss process, (ii) that an analogous method can be used even on radiation sensitive materials through the newly established indirect recoil implantation process. (iii) that there is scope for treatment of truly immovable objects through the implantation of fission fragments, (iv) there is vast potential in the area of activation analysis. The current state of development of these methods which greatly extend the scope of conventional TLA will be briefly reviewed. Current applications of these and TLA in industry are discussed.« less
Iftikhar, Irim; Irfan, Seema; Farooqi, Joveria; Azizullah, Zahida; Hasan, Rumina
2017-01-01
With the rise in multidrug-resistant tuberculosis, there is a search for newer techniques that will rapidly detect drug-resistant Mycobacterium tuberculosis. Although molecular techniques can detect resistance, culture is still considered gold standard, especially in resource-limited settings where quick, cheap, and easy techniques are needed. The aim of the study was to evaluate microcolony method thin layer agar (TLA) for quick detection of resistance against the first- and second-line antituberculous drugs in clinical isolates. This was a cross-sectional study performed at Aga Khan University Hospital. A total of 87 Z-N stain smear-positive pulmonary samples were received and indirect drug susceptibility test (ID-DST) was performed using Lowenstein-Jensen and mycobacteria growth indicator tube. Direct DST was performed using TLA on 7H10 agar. TLA was observed twice weekly under microscope for 4 weeks. Sensitivity, specificity, and accuracy were calculated for TLA using indirect susceptibility method as the gold standard. Level of agreement was calculated using Kappa score. TLA showed sensitivity of 89% and 95.2% for isoniazid and rifampicin, while for ethionamide, ofloxacin, and injectable aminoglycosides, it was 96.6%, 92.1%, and 100%, respectively. Specificity for the first-line drugs was >95% while second-line drugs ranged from 70% to 100%. Mean time to positivity was 10.2 days by TLA as compared to 43.1 days by ID-DST. TLA is a quick and reliable method in identifying resistance, especially in resource-limited settings. However, additional liquid culture can be set up as backup, especially in patients on therapy to avoid false negative results.
Rubinstein, Mauricio; Gill, Inderbir S; Aron, Monish; Kilciler, Mete; Meraney, Anoop M; Finelli, Antonio; Moinzadeh, Ali; Ukimura, Osamu; Desai, Mihir M; Kaouk, Jihad; Bravo, Emmanuel
2005-08-01
We report a prospective, randomized comparison of transperitoneal laparoscopic adrenalectomy (TLA) vs retroperitoneal laparoscopic adrenalectomy (RLA) for adrenal lesions with long-term followup. Between December 1997 and November 1999, 57 consecutive eligible patients with surgical adrenal disease were prospectively randomized to undergo TLA (25) or RLA (32). Study exclusion criteria were patient age greater than 80 years, body mass index greater than 40, bilateral adrenalectomy and significant prior abdominal surgery in the quadrant of interest. Mean followup was 5.96 years in the 2 groups. The groups were matched in regard to patient age (p = 0.84), body mass index (p = 0.43), American Society of Anesthesiologists class (p = 0.81) and laterality (p = 0.12). Median adrenal mass size was 2.7 cm (range 1 to 9) in the TLA group and 2.6 cm (range 0.5 to 6) in the RLA group (p = 0.83). TLA was comparable to RLA in terms of operative time (130 vs 126.5 minutes, p = 0.64), estimated blood loss (p = 0.92), specimen weight (p = 0.81), analgesic requirements (p = 0.25), hospital stay (p = 0.56) and the complication rate (p = 0.58). One case per group was electively converted to open surgery. Pathology data on the intact extracted specimens were similar between the groups. Averaged convalescence was 4.7 weeks in the TLA group and 2.3 weeks in the RLA group (p = 0.02). During a mean followup of 6 years 2 patients in the TLA group had a late complication (port site hernia). Mortality occurred in 5 patients, including 1 with TLA and 4 with RLA, during the 6-year followup. For most benign adrenal lesions requiring surgery laparoscopic adrenalectomy can be performed safely and effectively by the transperitoneal or the retroperitoneal approach.
Total Leishmania antigens with Poly(I:C) induce Th1 protective response.
Sanchez, M V; Eliçabe, R J; Di Genaro, M S; Germanó, M J; Gea, S; García Bustos, M F; Salomón, M C; Scodeller, E A; Cargnelutti, D E
2017-11-01
Our proposal was to develop a vaccine based on total Leishmania antigens (TLA) adjuvanted with polyinosinic-polycytidylic acid [Poly(I:C)] able to induce a Th1 response which can provide protection against Leishmania infection. Mice were vaccinated with two doses of TLA-Poly(I:C) administered by subcutaneous route at 3-week interval. Humoral and cellular immune responses induced by the immunization were measured. The protective efficacy of the vaccine was evaluated by challenging mice with infective promastigotes of Leishmania (Leishmania) amazonensis into the footpad. Mice vaccinated with TLA-Poly(I:C) showed a high anti-Leishmania IgG titre, as well as increased IgG1 and IgG2a subclass titres compared with mice vaccinated with the TLA alone. The high IgG2a indicated a Th1 bias response induced by the TLA-Poly(I:C) immunization. Accordingly, the cellular immune response elicited by the formulation was characterized by an increased production of IFN-γ and no significant production of IL-4. The TLA-Poly(I:C) immunization elicited good protection, which was associated with decreased footpad swelling, a lower parasite load and a reduced histopathological alteration in the footpad. Our findings demonstrate a promising vaccine against cutaneous leishmaniasis that is relatively economic and easy to develop and which should be taken into account for preventing leishmaniasis in developing countries. © 2017 John Wiley & Sons Ltd.
[Seven Cases of Surgery for Breast Cancer under Tumescent Local Anesthesia].
Hosoya, Tokuko; Nakagawa, Tsuyoshi; Oda, Goshi; Uetake, Hiroyuki
2015-11-01
Surgical procedures for breast cancer are usually performed under general anesthesia. However, general anesthesia needs to be avoided in some cases due to patient-related factors such as the presence of comorbid diseases. In these cases, we perform surgery under tumescent local anesthesia(TLA)in our department. Seven patients who were diagnosed with breast cancer underwent surgery under TLA instead of general anesthesia due to their comorbidities. The planned surgical procedures were successfully completed under TLA. A shift to general anesthesia could be avoided in all cases. The operative procedures for the breasts included modified radical mastectomy (Bt) in 3 cases and wide excision (Bp) in 4 cases. In addition, axillary lymph node dissection was performed in 2 cases; sampling, in 1 case; sentinel lymph node biopsy, in 2 cases; and no procedure for the axilla, in 2 cases. In terms of anesthesia, 2 cases were managed under TLA alone and 5 cases were managed under TLA combined with epidural anesthesia. Lidocaine was used for local anesthesia and did not reach the maximal permissive dose in all cases. No postoperative complication was observed. No local recurrence or new metastasis was observed during the observation period, which ranged from 1 to 67 months after the surgery. These findings demonstrate that surgery for breast cancer under TLA is safe and offers high curability for patients at high risk for complications of general anesthesia.
Habbema, Louis
2010-06-01
Lidocaine toxicity is a potential complication related to using tumescent local anesthesia (TLA) as the exclusive form of pain management in surgical procedures. We sought to determine the minimum concentration of lidocaine in the tumescent solution required to provide adequate anesthesia in patients undergoing liposuction using TLA exclusively. Liposuction using TLA exclusively was performed in 3430 procedures by the same surgeon. The initial concentration of 1000 mg/L lidocaine in the tumescent solution was gradually reduced to find the minimum required for adequate anesthesia. Adequate anesthesia was achieved using a lidocaine concentration of 500 mg/L saline in all areas treated and 400 mg/L saline for most of the areas treated. Data are based on the specific TLA technique used by the same surgeon. Lidocaine serum levels were not analyzed. For patients undergoing liposuction using TLA exclusively, the concentration of lidocaine in the normal saline solution required for adequate anesthesia is 400 mg/L for most body areas and 500 mg/L for some sensitive areas. Copyright 2009 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.
Kirst, Henning; Melis, Anastasios
2014-01-01
The concept of the Truncated Light-harvesting chlorophyll Antenna (TLA) size, as a tool by which to maximize sunlight utilization and photosynthetic productivity in microalgal mass cultures or high-density plant canopies, is discussed. TLA technology is known to improve sunlight-to-product energy conversion efficiencies and is hereby exemplified by photosynthetic productivity estimates of wild type and a TLA strain under simulated mass culture conditions. Recent advances in the generation of TLA-type mutants by targeting genes of the chloroplast signal-recognition particle (CpSRP) pathway, affecting the thylakoid membrane assembly of light-harvesting proteins, are also summarized. Two distinct CpSRP assembly pathways are recognized, one entailing post-translational, the other a co-translational mechanism. Differences between the post-translational and co-translational integration mechanisms are outlined, as these pertain to the CpSRP-mediated assembly of thylakoid membrane protein complexes in higher plants and green microalgae. The applicability of the CpSRP pathway genes in efforts to generate TLA-type strains with enhanced solar energy conversion efficiency in photosynthesis is evaluated. © 2013.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lopez-Menchero, E.; Centeno, J.; Magni, G.
1962-03-01
The extraction of traces of Ru, Zr, Nb, Ce, and U at low concentrations (5 mg/l in aqueous solution) from nitric acid solutions using trilauryl amine (TLA) has been experimentally studied. TLA will eventually be used for final purification of plutonium. Room-temperature data on plutonium contaminant distribution between aqueous solutions of varying nitric acid concentrations and a Shellsol-T solution containing l0% TlA and 5% octyl alcohol are presented. Within the temperature and nitric acid concentration ranges tested, the extractability of uranium increased with increased acid concentrations, although acid concentration in the aqueous phase had no effect on the decontamination factorsmore » for the main fission products. (H.G.G.)« less
Martin, Anandi; Munga Waweru, Peter; Babu Okatch, Fred; Amondi Ouma, Naureen; Bonte, Laurence; Varaine, Francis; Portaels, Françoise
2009-01-01
The objective of this study was to evaluate the performance of a low-cost method, the thin layer agar (TLA) method, for the diagnosis of smear-negative patients. This prospective study was performed in Homa Bay District Hospital in Kenya. Out of 1,584 smear-negative sputum samples, 212 (13.5%) were positive by culture in Löwenstein-Jensen medium (LJ) and 220 (14%) were positive by the TLA method. The sensitivities of LJ and TLA were 71% and 74%, respectively. TLA could become an affordable method for the diagnosis of smear-negative tuberculosis in resource-limited settings, with results available within 2 weeks. PMID:19494065
W. K. Smith; A. W. Schoettle; M. Cui
1991-01-01
Net CO(2) uptake in full sunlight, total leaf area (TLA), projected leaf area of detached leaves (PLA), and the silhouette area of attached leaves in their natural orientation to the sun at midday on June 1 (SLA) were measured for sun shoots of six conifer species. Among species, TLA/SLA ranged between 5.2 and 10.0 (x bar = 7.3), TLA/PLA ranged between 2.5 and 2.9 (x...
Thin layer activation techniques at the U-120 cyclotron of Bucharest
NASA Astrophysics Data System (ADS)
Constantinescu, B.; Ivanov, E. A.; Pascovici, G.; Popa-Simil, L.; Racolta, P. M.
1994-05-01
The Thin Layer Activation (TLA) technique is a nuclear method especially used for different types of wear (or corrosion) investigations. Experimental results for selection criteria of nuclear reactions for various tribological studies, using the IPNE U-120 classical variable energy Cyclotron are presented. Measuring methods for the main types of wear phenomena and home made instrumentations dedicated for TLA industrial applications are also reported. Some typical TLA tribological applications, a nuclear scanning method to obtain wear profile of piston-rings are presented as well.
Abimussi, Caio J X; Menegheti, Thais M; Wagatsuma, Juliana T; Floriano, Beatriz P; Arruda, André M M; dos Santos, Paulo S P; Oliva, Valéria N L S
2014-09-01
To compare two concentrations of ropivacaine administered for tumescent local anesthesia (TLA) in dogs undergoing mastectomy. Prospective randomized clinical study. Seventeen bitches of various breeds, aged 12 ± 2 years and weighing 10 ± 6.5 kg requiring total unilateral or bilateral mastectomy. Dogs were premedicated with acepromazine (0.04 mg kg(-1) ) and morphine (0.4 mg kg(-1) ) intramuscularly. Anesthesia was induced with propofol (2.5 mg kg(-1) ) and midazolam (0.2 mg kg(-1) ) intravenously, followed by intubation and maintenance with isoflurane and TLA. Dogs were randomly allocated to receive TLA either with 0.1% ropivacaine (group G1) or with 0.05% ropivacaine (group G05). TLA was performed by insertion of a multihole needle under the skin and infusion of ropivacaine and lactated Ringer's solution at a fixed volume of 15 mL kg(-1) . Ropivacaine concentrations in arterial blood were measured by high-performance liquid chromatography. Post-operative pain was assessed using two scales (University of Melbourne pain scale and a modified composite measure pain scale) and von Frey filaments, 4 hours after TLA and at 1 hour intervals until sensitivity was regained. A score above 30% of the maximum possible score was considered a positive indicator of pain. Peak plasma concentrations of ropivacaine were measured 240 minutes after TLA in G1. Low concentrations were measured in G05 for 60 minutes, with subsequent increase. Analgesic rescue and return of sensitivity occurred at 7 ± 2.3 and 7 ± 1.9 hours (mean ± SD) after TLA for G1 and G05, respectively. Tumescent local anesthesia with ropivacaine provided satisfactory post-operative analgesia that lasted for several hours, with no difference in duration between the concentrations. No serious side effects were attributed to TLA. Results indicated that 0.05% ropivacaine provided adequate analgesia for mastectomy, however, more studies are required to support this conclusion. © 2014 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.
Chadha, Neil K; Lam, Gilbert O A; Ludemann, Jeffrey P; Kozak, Frederick K
2013-12-01
To our knowledge, the present study is the first double-blind, randomized, placebo-controlled trial in children to compare nasal preparation sprays administered before flexible nasendoscopy with placebo. To compare the degree of pain experienced by children undergoing flexible nasendoscopy after 1 of 3 intranasal sprays: placebo, decongestant with topical local anesthetic (TLA), or decongestant without TLA. A randomized placebo-controlled trial with blinding of participants, caregivers, observers, and otolaryngologists was conducted in a tertiary pediatric otolaryngology ambulatory clinic. Participants included a consecutive sample of children aged 3 to 12 years requiring flexible nasendoscopy. Exclusion criteria included concomitant respiratory tract infection, known allergy to a trial agent, or previous flexible nasendoscopy. One hundred fifty-one children were assessed for eligibility; 24 eligible children refused participation and 69 were included and block-randomized. All completed the study, and there were no adverse events. Nasal spray administration of placebo (normal saline); xylometazoline hydrochloride, 0.05% (decongestant); or lidocaine hydrochloride, 1%, with xylometazoline hydrochloride, 0.05% (TLA with decongestant) was performed 10 minutes before flexible nasendoscopy. Primary outcome measure was the child-reported Wong-Baker Faces Pain (WBFP) scale. Secondary outcomes included the caregiver-proxy WBFP scale; the Face, Legs, Activity, Cry, and Consolability (FLACC) scale; and the physician-reported Difficulty of Procedure Visual Analog Scale (DPVAS). Twenty-three children were recruited in each of the intervention arms. Baseline characteristics were comparable between groups. The mean child-rated WBFP scale scores were 2.4, 1.8, and 2.2 for the placebo, decongestant, and TLA with decongestant groups, respectively (P = .45). Although the finding was statistically nonsignificant, decongestant had the lowest mean caregiver-proxy WBFP scale score, lowest observer-rated FLACC scale score, and highest physician-rated DPVAS score. Subgroup analysis did not demonstrate any correlation between the outcomes and age or sex. This study revealed no statistically significant difference in the discomfort experienced by children undergoing flexible nasendoscopy after placebo, decongestant, or TLA with decongestant. Decongestant was associated with the least discomfort (on child, caregiver, and observer-rated pain scale scores) and the lowest rating for difficulty of procedure. With these findings, the study suggests that there is no significant benefit of topical decongestant with or without TLA compared with placebo in reducing pain associated with pediatric flexible nasendoscopy. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01351298.
NASA Technical Reports Server (NTRS)
Suderman, M. T.; McCarthy, M.; Mossell, E.; Watts, D. M.; Peters, C. J.; Shope, R.; Goodwin, T. J.
2006-01-01
A three-dimensional (3-D) tissue-like assembly (TLA) of human bronchial-tracheal mesenchymal (HBTC) cells with an overlay of human bronchial epithelial (BEAS-2B) cells was constructed using a NASA Bioreactor to survey the infectivity of SARS-CoV. This TLA was inoculated with a low passage number Urbani strain of SARS-CoV. At selected intervals over a 10-day period, media and cell aliquots of the 3-D TLA were harvested for viral titer assay and for light and electron microscopy examination. All viral titer assays were negative in both BEAS-2B two-dimensional monolayer and TLA. Light microscopy immunohistochemistry demonstrated antigen-antibody reactivity with anti-SARS-CoV polyclonal antibody to spike and nuclear proteins on cell membranes and cytoplasm. Coronavirus Group 2 cross-reactivity was demonstrated by positive reaction to anti-FIPV 1 and anti-FIPV 1 and 2 antibodies. TLA examination by transmission electron microscopy indicated increasing cytoplasmic vacuolation with numerous electron-dense bodies measuring 45 to 270 nm from days 4 through 10. There was no evidence of membrane blebbing, membrane duplication, or fragmentation of organelles in the TLAs. However, progressive disruption of endoplasmic reticulum was observed throughout the cells. Antibody response to SARS-CoV specific spike and nucleocapsid glycoproteins, cross-reactivity with FIPV antibodies, and the cytoplasmic pathology suggests this HBTE TLA model is permissive to SARS-CoV infection.
Potential of used frying oil in paving material: solution to environmental pollution problem.
Singh-Ackbarali, Dimple; Maharaj, Rean; Mohamed, Nazim; Ramjattan-Harry, Vitra
2017-05-01
The improper disposal of used frying oil (UFO) presents numerous ecological, environmental and municipal problems. Of great concern is the resultant blockage of municipal drainage systems and water treatment facilities, harm to wildlife when they become coated in it and detriment to aquatic life and ecosystems due to the depletion of the oxygen content in water bodies such as rivers and lakes that have become contaminated. Statistics show that in Trinidad and Tobago, in excess of one million liters of used cooking oil is collected annually from various restaurant chains. This paper investigated the potential of using UFO as a performance enhancing additive for road paving applications utilizing Trinidad Lake Asphalt (TLA) and Trinidad Petroleum Bitumen (TPB) as a mitigation strategy for improper UFO disposal. Modified blends containing various additions of UFO (2-10% wt) were prepared for the TLA and TPB asphaltic binders. Results demonstrated in terms of stiffness, increasing the dosage of UFO in TLA and TPB base binders resulted in a gradual decrease in stiffness (G* value decreased). In terms of elasticity, increasing the dosage of the UFO additive in TLA resulted in a general decrease in the elasticity of the blends indicated by an increase in phase angle or phase lag (δ). Increasing dosages of the UFO additive in TPB resulted in a significant decrease in δ where the most elastic blend was at the 6% UFO level. TLA and UFO-TLA modified blends exhibited significantly lower values of δ and higher values of G* confirming the superiority of the TLA material. Incorporation of the UFO in the blends led to a decrease in the rutting resistance and increase in the fatigue cracking resistance (decrease in G*/sinδ and G*sinδ, respectively). This study highlighted the potential for the reuse of UFO as an asphalt modifier capable of producing customized UFO modified asphaltic blends for special applications and confirms its feasibility as an environmentally attractive means of reusing the waste/hazardous UFO material locally.
Battaglioli, T; Rintiswati, N; Martin, A; Palupi, K R; Bernaerts, G; Dwihardiani, B; Ahmad, R A; Matthys, F; Mahendradhata, Y; Van der Stuyft, P
2013-11-01
Sputum smear microscopy for the diagnosis of tuberculosis (TB) is cheap and simple but its sensitivity is low. Culture on Löwenstein-Jensen (LJ) is more sensitive but it takes a long time to yield results. Thin-Layer Agar (TLA) culture was suggested as an equally sensitive and faster alternative. We evaluated the performance of TLA for diagnosing TB in Jogjakarta, Indonesia. People with suspected TB presenting from July 2010 to July 2011 to two chest clinics of the National TB Control Programme network of Jogjakarta were eligible for inclusion. A sputum sample was sent to the Gadjah Mada University microbiology laboratory for concentration, smearing, Ziehl-Neelsen staining and culture on LJ and TLA. Sensitivity of cultures was evaluated against a composite reference standard (any positive culture). Time to detection of Mycobacteria was recorded. Out of 1414 samples, 164 (12%) were smear positive, 99 (7%) were scanty and 1151 (81%) were negative. On TLA and LJ respectively, 168 (12%) and 149 (11%) samples were positive, 72 (5%) and 32 (2%) were contaminated (κ = 0.64; 95% CI 0.59-0.69, p <0.01). Using the reference standard, 196 (14%) TB cases were identified. The sensitivity of TLA was 0.86 (95% CI 0.80-0.90), significantly higher (p 0.03) than for LJ (0.76; 95% CI 0.69-0.81). The median time to detection in days was significantly shorter (p <0.01) for TLA (12; 95% CI 11-13) than for LJ (44; 95% CI 43-45). TLA is a rapid and sensitive method for the diagnosis of TB. Implementation studies to evaluate the cost-effectiveness and impact of its introduction into programmatic settings are urgently needed. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.
Multiferroicity in the generic easy-plane triangular lattice antiferromagnet RbFe(MoO4)2
NASA Astrophysics Data System (ADS)
White, J. S.; Niedermayer, Ch.; Gasparovic, G.; Broholm, C.; Park, J. M. S.; Shapiro, A. Ya.; Demianets, L. A.; Kenzelmann, M.
2013-08-01
RbFe(MoO4)2 is a quasi-two-dimensional (quasi-2D) triangular lattice antiferromagnet (TLA) that displays a zero-field magnetically driven multiferroic phase with a chiral spin structure. By inelastic neutron scattering, we determine quantitatively the spin Hamiltonian. We show that the easy-plane anisotropy is nearly 1/3 of the dominant spin exchange, making RbFe(MoO4)2 an excellent system for studying the physics of the model 2D easy-plane TLA. Our measurements demonstrate magnetic-field-induced fluctuations in this material to stabilize the generic finite-field phases of the 2D XY TLA. We further explain how Dzyaloshinskii-Moriya interactions can generate ferroelectricity only in the zero-field phase. Our conclusion is that multiferroicity in RbFe(MoO4)2, and its absence at high fields, results from the generic properties of the 2D XY TLA.
Conteduca, V; Scarpi, E; Caroli, P; Salvi, S; Lolli, C; Burgio, S L; Menna, C; Schepisi, G; Testoni, S; Gurioli, G; Paganelli, G; Casadio, V; Matteucci, F; De Giorgi, U
2017-11-14
The association between choline uptake and androgen receptor (AR) expression is suggested by the upregulation of choline kinase-alpha in prostate cancer. Recently, detection of AR aberration in cell-free DNA as well as early 18F-fluorocholine positron emission tomography/computed tomography (FCH-PET/CT) were associated with outcome in metastatic castration-resistant prostate cancer (mCRPC) patients treated with abiraterone and enzalutamide. We aimed to make a direct comparison between circulating AR copy number (CN) and choline uptake at FCH-PET/CT. We analysed 80 mCRPC patients progressing after docetaxel treated with abiraterone (n = 47) or enzalutamide (n = 33). We analysed AR CN from plasma samples using digital PCR and Taqman CN assays and total lesion activity (TLA) and metabolic tumor volume (MTV) on FCH-PET/CT at baseline. A meaningful correlation was showed among AR gain and TLA/MTV compared to AR non-gained cases (P = 0.001 and P = 0.004, respectively), independently from type of treatment. Multivariate analysis revealed that AR CN and only TLA were associated with both shorter PFS (P < 0.0009 and P = 0.026, respectively) and OS (P < 0.031 and P = 0.039, respectively). AR gain appeared significantly correlated with choline uptake represented mainly by TLA. Further prospective studies are warranted to better address this pathway of AR-signalling and to identify multiplex biomarker strategies including plasma AR and FCH-PET/CT in mCRPC patients.
Regional variations in the presentation and surgical management of Pierre Robin sequence.
Scott, Andrew R; Mader, Nicholas S
2014-12-01
To estimate the current birth prevalence of isolated and syndromic Pierre Robin sequence (iPRS and sPRS), including demographic variations. To assess for regional variations in surgical airway interventions for PRS, and to determine the mean length of stay (LOS), cost of admission, complication rate, and rate of associated procedures related to tongue-lip adhesion (TLA), neonatal mandibular distraction osteogenesis (MDO), and tracheotomy. Retrospective cross-sectional study. The 2006 and 2009 Kids Inpatient Databases were used to identify newborns and infants with PRS; analysis using cross tabulations and linear regression modeling was performed. In 2006 and 2009, the estimated birth prevalence of iPRS was 1.8:10,000 live births and sPRS 1.4:10,000 live births. The highest rate was in whites and the lowest in non-Hispanic blacks. There were 145 TLAs (36%), 176 MDOs (43%), and 85 tracheotomies (21%). The Northeast favored a TLA strategy; the Midwest favored MDO. The mean LOS for TLA was 24.5 days, MDO 36.7 days, tracheotomy (iPRS) 44.9 days, and tracheotomy (sPRS) 53.0 days. The birth prevalence of PRS may be higher than previously described, especially in whites. Surgical management strategies vary between regions. The overall cost of a TLA admission is lower than an MDO or tracheotomy admission, owing primarily to shorter LOS. This study was limited by not taking into account outpatient expenses (nursing care, monitoring) or need for further airway/feeding intervention over subsequent admissions. 2c. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.
Resnick, Cory M; Dentino, Kelley; Katz, Eliot; Mulliken, John B; Padwa, Bonnie L
2016-09-01
Tongue-lip adhesion (TLA) is commonly used to relieve obstructive sleep apnea (OSA) in infants with Robin sequence (RS), but few studies have evaluated its efficacy with objective measures. The purpose of this study was to measure TLA outcomes using polysomnography. Our hypothesis was that TLA relieves OSA in most infants. This is a retrospective study of infants with RS who underwent TLA from 2011 to 2014 and had at least a postoperative polysomnogram. Predictor variables included demographic and birth characteristics, surgeon, syndromic diagnosis, GILLS score, preoperative OSA severity, and clinical course. A successful outcome was defined as minimal OSA (apnea-hypopnea index score < 5) on postoperative polysomnogram and no need for additional airway intervention. Descriptive, bivariate, and regression statistics were computed, and statistical significance was set at P < .05. Eighteen subjects who had TLA at a mean age of 28 ± 4.7 days were included. Thirteen (72.2%) had a confirmed or suspected syndrome, and the mean GILLS score was 3 ± 0.3. All parameters trended toward improvement from the preoperative to postoperative polysomnograms, and improvement in OSA severity, oxygen saturation nadir, and arousals per hour was statistically significant (P < .02). This effect was significant across categories of surgeon, syndrome, and GILLS score. Nine subjects (50%) met the criteria for a successful outcome. Bivariate and regression analyses did not demonstrate a significant relationship between success and any predictor variable. TLA improved airway obstruction in all infants with RS but resolved OSA in only nine patients, and success was unpredictable.
Nonaka, Kouichi; Ohata, Ken; Matsuhashi, Nobuyuki; Shimizu, Michio; Arai, Shin; Hiejima, Yoshimitsu; Kita, Hiroto
2014-05-01
Endoscopic diagnosis of stomach mucosa-associated lymphoid tissue (MALT) lymphoma is often difficult because few specific findings are indicated. Even when MALT lymphoma is suspected by endoscopy, it is still difficult to make a definitive diagnosis by biopsy because lymphoma cells sometimes distribute unevenly. We previously reported that a tree-like appearance (TLA) is a characteristic finding of MALT lymphoma by narrow-band imaging (NBI) magnifying endoscopy and it is valuable in the selection of an optimal biopsy site in MALT lymphoma. Here, we study the frequency of TLA and evaluate the relationship between the response to eradication therapy and TLA in MALT lymphoma. We retrospectively examined the clinical background, endoscopic findings, response to eradication therapy, and Helicobacter pylori infection status of 16 patients diagnosed with MALT lymphoma who were referred to our hospital from April 2007 to August 2012. The regimen for eradicationtherapy consisted of rabeprazole, with amoxicillin and clarithromycin, all given for 7 days. TLA was found in 75% (12/16) and H. pylori infection in 75% (12/16) of patients diagnosed with MALT lymphoma by NBI magnifying endoscopy. In all complete regression (CR) patients after eradication treatment, the TLA finding had disappeared (100%); however, in the non-CR patients, TLA remained the same as before the eradication therapy (P=0.002). These results suggest that NBI magnifying endoscopy may be useful not only in the diagnosis but also in the evaluation of the response to eradication therapy of MALT lymphoma of the stomach. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.
Photosynthetic antenna engineering to improve crop yields.
Kirst, Henning; Gabilly, Stéphane T; Niyogi, Krishna K; Lemaux, Peggy G; Melis, Anastasios
2017-05-01
Evidence shows that decreasing the light-harvesting antenna size of the photosystems in tobacco helps to increase the photosynthetic productivity and plant canopy biomass accumulation under high-density cultivation conditions. Decreasing, or truncating, the chlorophyll antenna size of the photosystems can theoretically improve photosynthetic solar energy conversion efficiency and productivity in mass cultures of algae or plants by up to threefold. A Truncated Light-harvesting chlorophyll Antenna size (TLA), in all classes of photosynthetic organisms, would help to alleviate excess absorption of sunlight and the ensuing wasteful non-photochemical dissipation of excitation energy. Thus, solar-to-biomass energy conversion efficiency and photosynthetic productivity in high-density cultures can be increased. Applicability of the TLA concept was previously shown in green microalgae and cyanobacteria, but it has not yet been demonstrated in crop plants. In this work, the TLA concept was applied in high-density tobacco canopies. The work showed a 25% improvement in stem and leaf biomass accumulation for the TLA tobacco canopies over that measured with their wild-type counterparts grown under the same ambient conditions. Distinct canopy appearance differences are described between the TLA and wild type tobacco plants. Findings are discussed in terms of concept application to crop plants, leading to significant improvements in agronomy, agricultural productivity, and application of photosynthesis for the generation of commodity products in crop leaves.
Huang, Chiung-Chun; Chou, Dylan; Yeh, Che-Ming; Hsu, Kuei-Sen
2016-02-01
Fear memory-encoding thalamic input synapses to the lateral amygdala (T-LA) exhibit dynamic efficacy changes that are tightly correlated with fear memory strength. Previous studies have shown that auditory fear conditioning involves strengthening of synaptic strength, and conversely, fear extinction training leads to T-LA synaptic weakening and occlusion of long-term depression (LTD) induction. These findings suggest that the mechanisms governing LTD at T-LA synapses may determine the behavioral outcomes of extinction training. Here, we explored this hypothesis by implementing food deprivation (FD) stress in mice to determine its effects on fear extinction and LTD induction at T-LA synapses. We found that FD increased plasma acylated ghrelin levels and enhanced fear extinction and its retention. Augmentation of fear extinction by FD was blocked by pretreatment with growth hormone secretagogue receptor type-1a antagonist D-Lys(3)-GHRP-6, suggesting an involvement of ghrelin signaling. Confirming previous findings, two distinct forms of LTD coexist at thalamic inputs to LA pyramidal neurons that can be induced by low-frequency stimulation (LFS) or paired-pulse LFS (PP-LFS) paired with postsynaptic depolarization, respectively. Unexpectedly, we found that FD impaired the induction of PP-LFS- and group I metabotropic glutamate receptor agonist (S)-3,5-dihydroxyphenylglycine (DHPG)-induced LTD, but not LFS-induced LTD. Ghrelin mimicked the effects of FD to impair the induction of PP-LFS- and DHPG-induced LTD at T-LA synapses, which were blocked by co-application of D-Lys(3)-GHRP-6. The sensitivity of synaptic transmission to 1-naphthyl acetyl spermine was not altered by either FD or ghrelin treatment. These results highlight distinct features of fear extinction and LTD at T-LA synapses. Copyright © 2015 Elsevier Ltd. All rights reserved.
TLA-1: a New Plasmid-Mediated Extended-Spectrum β-Lactamase from Escherichia coli
Silva, J.; Aguilar, C.; Ayala, G.; Estrada, M. A.; Garza-Ramos, U.; Lara-Lemus, R.; Ledezma, L.
2000-01-01
Escherichia coli R170, isolated from the urine of an infected patient, was resistant to expanded-spectrum cephalosporins, aztreonam, ciprofloxacin, and ofloxacin but was susceptible to amikacin, cefotetan, and imipenem. This particular strain contained three different plasmids that encoded two β-lactamases with pIs of 7.0 and 9.0. Resistance to cefotaxime, ceftazidime, aztreonam, trimethoprim, and sulfamethoxazole was transferred by conjugation from E. coli R170 to E. coli J53-2. The transferred plasmid, RZA92, which encoded a single β-lactamase, was 150 kb in length. The cefotaxime resistance gene that encodes the TLA-1 β-lactamase (pI 9.0) was cloned from the transconjugant by transformation to E. coli DH5α. Sequencing of the blaTLA-1 gene revealed an open reading frame of 906 bp, which corresponded to 301 amino acid residues, including motifs common to class A β-lactamases: 70SXXK, 130SDN, and 234KTG. The amino acid sequence of TLA-1 shared 50% identity with the CME-1 chromosomal class A β-lactamase from Chryseobacterium (Flavobacterium) meningosepticum; 48.8% identity with the VEB-1 class A β-lactamase from E. coli; 40 to 42% identity with CblA of Bacteroides uniformis, PER-1 of Pseudomonas aeruginosa, and PER-2 of Salmonella typhimurium; and 39% identity with CepA of Bacteroides fragilis. The partially purified TLA-1 β-lactamase had a molecular mass of 31.4 kDa and a pI of 9.0 and preferentially hydrolyzed cephaloridine, cefotaxime, cephalothin, benzylpenicillin, and ceftazidime. The enzyme was markedly inhibited by sulbactam, tazobactam, and clavulanic acid. TLA-1 is a new extended-spectrum β-lactamase of Ambler class A. PMID:10722503
Comparison of two methods of standard setting: the performance of the three-level Angoff method.
Jalili, Mohammad; Hejri, Sara M; Norcini, John J
2011-12-01
Cut-scores, reliability and validity vary among standard-setting methods. The modified Angoff method (MA) is a well-known standard-setting procedure, but the three-level Angoff approach (TLA), a recent modification, has not been extensively evaluated. This study aimed to compare standards and pass rates in an objective structured clinical examination (OSCE) obtained using two methods of standard setting with discussion and reality checking, and to assess the reliability and validity of each method. A sample of 105 medical students participated in a 14-station OSCE. Fourteen and 10 faculty members took part in the MA and TLA procedures, respectively. In the MA, judges estimated the probability that a borderline student would pass each station. In the TLA, judges estimated whether a borderline examinee would perform the task correctly or not. Having given individual ratings, judges discussed their decisions. One week after the examination, the procedure was repeated using normative data. The mean score for the total test was 54.11% (standard deviation: 8.80%). The MA cut-scores for the total test were 49.66% and 51.52% after discussion and reality checking, respectively (the consequent percentages of passing students were 65.7% and 58.1%, respectively). The TLA yielded mean pass scores of 53.92% and 63.09% after discussion and reality checking, respectively (rates of passing candidates were 44.8% and 12.4%, respectively). Compared with the TLA, the MA showed higher agreement between judges (0.94 versus 0.81) and a narrower 95% confidence interval in standards (3.22 versus 11.29). The MA seems a more credible and reliable procedure with which to set standards for an OSCE than does the TLA, especially when a reality check is applied. © Blackwell Publishing Ltd 2011.
Morizane, Kazuki; Takahashi, Toshiaki; Konishi, Fumihiko; Yamamoto, Haruyasu
2011-12-01
A new radiographic method using the anterior and posterior femoral condyles as a landmark to determine the rotational alignment of the femoral component in TKA had been developed. The new radiograph presents an axial view of the distal femur. The patients were asked to lie in the supine position and flex the knee approximately 120° to 130°. Radiographs were applied at an inclination angle of 20° to 30°. The condylar twist angle (CTA), the external rotational angle between the posterior condylar (PC) line and the clinical transepicondylar axis (TEA), and the trochlear line angle (TLA), and the internal rotational angle between the anterior trochlear line and the clinical TEA were measured. Images were taken of 129 knees in 87 patients with osteoarthritis of the knee. The measurement values obtained using our method with those obtained using 3D reconstructed images from a 3-dimensional helical CT system (n = 35) were compared. The average CTA was 5.7° ± 2.8° and the average TLA was -5.6° ± 3.2°. The CTA was negatively correlated with the tibiofemoral angle (TFA). The average TLA was positively correlated with the TFA. The average difference between the TLA values obtained with this view and those obtained using the 3D-CT was 0.5° ± 1.6°. The relationship between the radiograph and 3D-CT in TLA was higher than that in CTA. This radiographic technique allows easy and simultaneous measurement of the CTA and TLA and may provide an alternative method for assessing the TEA of the femur during preoperative planning for TKA.
TLA-1: a new plasmid-mediated extended-spectrum beta-lactamase from Escherichia coli.
Silva, J; Aguilar, C; Ayala, G; Estrada, M A; Garza-Ramos, U; Lara-Lemus, R; Ledezma, L
2000-04-01
Escherichia coli R170, isolated from the urine of an infected patient, was resistant to expanded-spectrum cephalosporins, aztreonam, ciprofloxacin, and ofloxacin but was susceptible to amikacin, cefotetan, and imipenem. This particular strain contained three different plasmids that encoded two beta-lactamases with pIs of 7.0 and 9.0. Resistance to cefotaxime, ceftazidime, aztreonam, trimethoprim, and sulfamethoxazole was transferred by conjugation from E. coli R170 to E. coli J53-2. The transferred plasmid, RZA92, which encoded a single beta-lactamase, was 150 kb in length. The cefotaxime resistance gene that encodes the TLA-1 beta-lactamase (pI 9.0) was cloned from the transconjugant by transformation to E. coli DH5alpha. Sequencing of the bla(TLA-1) gene revealed an open reading frame of 906 bp, which corresponded to 301 amino acid residues, including motifs common to class A beta-lactamases: (70)SXXK, (130)SDN, and (234)KTG. The amino acid sequence of TLA-1 shared 50% identity with the CME-1 chromosomal class A beta-lactamase from Chryseobacterium (Flavobacterium) meningosepticum; 48.8% identity with the VEB-1 class A beta-lactamase from E. coli; 40 to 42% identity with CblA of Bacteroides uniformis, PER-1 of Pseudomonas aeruginosa, and PER-2 of Salmonella typhimurium; and 39% identity with CepA of Bacteroides fragilis. The partially purified TLA-1 beta-lactamase had a molecular mass of 31.4 kDa and a pI of 9.0 and preferentially hydrolyzed cephaloridine, cefotaxime, cephalothin, benzylpenicillin, and ceftazidime. The enzyme was markedly inhibited by sulbactam, tazobactam, and clavulanic acid. TLA-1 is a new extended-spectrum beta-lactamase of Ambler class A.
Schmittner, M D; Faulhaber, J; Kemler, B; Koenen, W; Thumfart, J O; Weiss, C; Neumaier, M; Beck, G C
2010-12-01
Tumescent local anaesthesia (TLA) with high prilocaine doses leads to formation of methemoglobin (MHb) which is known to be a potent activator of pro-inflammatory endothelial cell response in vitro. As TLA is widely used for large dermatological resections, the aim of this study was to investigate the effects of high prilocaine doses on the systemic inflammatory response in vivo and its clinical relevance. This prospective study examines the influence of MHb on serum interleukin (IL)-6, IL-8 and tumour necrosis tumour necrosis (TNF)-α levels up to 72 h after application of TLA with prilocaine in doses higher than 600 mg. A total of 30 patients received prilocaine in a median dose of 1500 mg (range: 880-4160 mg) for large resections. Peak prilocaine serum concentration was reached 4 h (0.72 ± 0.07 μg/mL), the maximum concentration of MHb (7.43 ± 0.87%) and IL-6 (28.4 ± 4.1 U/L) 12 h after TLA application. TNF-α and IL-8 release were not found significantly increased. Three patients developed MHb concentrations >15%. This clinical study shows for the first time that a high prilocaine serum concentration leads in vivo to elevated systemic levels of IL-6 but not of IL-8 and TNF-α because of initial high MHb levels. Because of possible and unpredictable high MHb concentrations, TLA should only be performed with prilocaine in doses of 2.5 mg/kg. In general, new solutions of TLA are necessary to achieve adequate anaesthesia for large dermatological resections to decrease the risk of methemoglobinaemia. © 2010 The Authors. Journal compilation © 2010 European Academy of Dermatology and Venereology.
Indirect radioimmunoassay for thymus leukemia (TL) antigens. [Mice, /sup 125/I tracer technique
DOE Office of Scientific and Technical Information (OSTI.GOV)
Esmon, N.L.; Little, J.R.
1976-09-01
An indirect radioimmunoassay for thymus leukemia TL antigens has been developed and its specificity documented. The assay makes use of anti-TL antibodies produced in congenic mice (A-Tla/sup b/) and radioiodinated purified rabbit anti-mouse IgG. Using this assay, differences can be detected in the amounts of antigen expressed on thymocytes of the three known phenotypes (TL.1,2,3; TL.2; TL/sup -/) of inbred mouse strains. Significant differences are also detected in comparison of the thymocytes from homozygous TL.1,2,3 mice (A-Tla/sup a/) and heterozygotes from Tla/sup a/ and Tla/sup b/ parents. Optimum conditions for the assay have been established. Its ability to detect antigensmore » on glutaraldehyde-fixed cells and the binding of noncytolytic antibodies on both viable and fixed cells are documented. The assay has also been used to quantitate the changes in TL antigen expression on cells incubated in anti-TL antisera under conditions of antigenic modulation.« less
Boyle, Robert J; Pedroletti, Christophe; Wickman, Magnus; Bjermer, Leif; Valovirta, Erkka; Dahl, Ronald; Von Berg, Andrea; Zetterström, Olof
2011-01-01
Objective To determine whether environmental control using nocturnal temperature controlled laminar airflow (TLA) treatment could improve the quality of life of patients with persistent atopic asthma. Design Randomised, double-blind, placebo-controlled, parallel-group trial. Setting Nineteen European asthma clinics. Participants 312 patients aged 7–70 with inadequately controlled persistent atopic asthma. Main outcome measure Proportion of patients with an increase of ≥0.5 points in asthma quality of life score after 1 year of treatment. Results TLA devices were successfully installed in the bedrooms of 282 (90%) patients included in the primary efficacy analysis. There was a difference in treatment response rate between active (143 of 189, 76%) and placebo (56 of 92, 61%) groups, difference 14.8% (95% CI 3.1 to 26.5, p=0.02).3 In patients aged ≥12, on whom the study was powered, the difference in response rate was similar-active 106 of 143 (74%), placebo 42 of 70 (60%), difference 14.1% (0.6 to 27.7, p=0.059). There was a difference between groups in fractional exhaled nitric oxide change of −7.1 ppb (−13.6 to −0.7, p=0.03). Active treatment was associated with less increase in cat-specific IgE than placebo. There was no difference in adverse event rates between treatment groups. Conclusion Inhalant exposure reduction with TLA improves quality of life, airway inflammation and systemic allergy in patients with persistent atopic asthma. TLA may be a treatment option for patients with inadequately controlled persistent atopic asthma. Trial registration number Clinical Trials NCT00986323. PMID:22131290
H-T Magnetic Phase Diagram of a Frustrated Triangular Lattice Antiferromagnet CuFeO 2
NASA Astrophysics Data System (ADS)
Mitsuda, Setsuo; Mase, Motoshi; Uno, Takahiro; Kitazawa, Hideaki; Katori, Hiroko
2000-01-01
By magnetization and specific heat measurements in an applied magnetic field up to 12 T, we obtained the magnetic field (H) versus temperature (T) phase diagram of a frustrated triangular lattice antiferromagnet (TLA), CuFeO2, where a partially disordered phase typical to Ising TLA exists as a thermally induced state for the 4-sublattice ground state as well as for the first-field-induced 5-sublattice-like state. The experimentally obtained H-T magnetic phase diagram is compared with that from Monte-Carlo simulation of a 2D Ising TLA model with competing exchange interactions up to 3rd neighbors.
Teacher Leadership Academy: Achieving Systemic School Improvement.
ERIC Educational Resources Information Center
Davidson, Lynn; Garton, Susan; Manges, Charles D.
This study investigated professional development as provided through the Teacher Leadership Academy (TLA) model used in rural Illinois area school districts and district consortia. Surveys were distributed to TLA participants that sought their perceptions of the desirability, involvement, and feasibility of school reform in general and the…
Integration of Diagnostic Microbiology in a Model of Total Laboratory Automation.
Da Rin, Giorgio; Zoppelletto, Maira; Lippi, Giuseppe
2016-02-01
Although automation has become widely utilized in certain areas of diagnostic testing, its adoption in diagnostic microbiology has proceeded much more slowly. To describe our real-world experience of integrating an automated instrument for diagnostic microbiology (Walk-Away Specimen Processor, WASPLab) within a model of total laboratory automation (TLA). The implementation process was divided into 2 phases. The former period, lasting approximately 6 weeks, entailed the installation of the WASPLab processor to operate as a stand-alone instrumentation, whereas the latter, lasting approximately 2 weeks, involved physical connection of the WASPLab with the automation. Using the WASPLab instrument in conjunction with the TLA model, we obtained a time savings equivalent to the work of 1.2 full-time laboratory technicians for diagnostic microbiology. The connection of WASPLab to TLA allowed its management by a generalist or clinical chemistry technician, with no need for microbiology skills on the part of either worker. Hence, diagnostic microbiology could be performed by the staff that is already using the TLA, extending their activities to include processing urgent clinical chemistry and hematology specimens. The time to result was also substantially improved. According to our experience, using the WASPLab instrument as part of a TLA in diagnostic microbiology holds great promise for optimizing laboratory workflow and improving the quality of testing. © American Society for Clinical Pathology, 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Ardizzoni, E; Mulders, W; Sanchez-Padilla, E; Varaine, F; de Jong, B C; Rigouts, L
2014-08-01
Long transportation times of samples to culture laboratories can lead to higher contamination rates and significant loss of viability, resulting in lower culture positivity rates. Thin-layer agar (TLA) is a sensitive culture method for the isolation of Mycobacterium tuberculosis that has been optimised with N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH) decontaminated samples. The combination of the TLA culture method and other decontamination procedures has not been extensively validated. Among 390 smear-positive samples, we compared the culture positivity of samples decontaminated using the Petroff method vs. NALC-NaOH neutralised with phosphate buffer (PBS), applied to samples preserved with cetylpyridinium chloride (CPC) or CPC-free, and then of CPC-preserved samples decontaminated with NALC-NaOH neutralised using Difco neutralising buffer. The sediments were inoculated on TLA, and then on MGIT 960 or Löwenstein-Jensen (LJ) as gold standards. Decontamination with NALC-NaOH yielded higher culture positivity in TLA than in the Petroff method, which was further enhanced by neutralising CPC with the Difco buffer. Surprisingly, culture positivity on LJ also increased after using Difco buffer, suggesting that CPC may not be completely neutralised in egg-based medium. After transportation in CPC, decontamination using NALC-NaOH followed by neutralisation using Difco buffer resulted in the best recovery rates for samples inoculated on TLA and on LJ.
Ardizzoni, E; Mulders, W; Kotrikadze, T; Aspindzelashvili, R; Goginashvili, L; Pangtey, H; Varaine, F; Bastard, M; Rigouts, L; de Jong, B C
2015-12-01
Molecular techniques rapidly detect resistance to rifampicin (RMP) and isoniazid (INH), but do not eliminate the need for culture-based drug susceptibility testing (DST) against other drugs. The thin-layer agar (TLA) test, a non-commercial direct DST method, has demonstrated good performance for INH and RMP; however, evidence is still limited, and its applicability for DST of ofloxacin (OFX) and kanamycin (KM) is unknown. We compared 279 TLA DST results with those of MGIT for INH and RMP, and 280 results for OFX and KM with those of the 7H11 agar proportion method, obtained from 320 smear-positive samples from 165 Georgian TB patients. Discrepancies were solved by comparison with a composite reference standard. The prevalence of multidrug-resistant tuberculosis (TB) was 30 of 164 patients (18.3%), 2 (6.7%) of whom had extensively drug-resistant TB. TLA showed 94.7%, 98.2%, 100% and 78.9% sensitivity, respectively, for INH, RMP, OFX and KM, with 100% specificity. Average time to results was 7 days in TLA, 23 in MGIT and 49 for 7H11 agar. In low-resource settings, TLA can be applied for the rapid detection of resistance to INH, RMP and fluoroquinolones. Further studies are necessary to improve sensitivity to KM and further assess its performance for OFX and other drugs and its applicability in field conditions.
[Effect of the thyroid status on the proteinases/inhibitors system under stress].
Gorodetskaya, I V; Gusakova, E A
2015-01-01
Тhe alarm-stage of stress reaction (аn hour after the stress of swimming of rats in a cage during an hour) is characterized by the stimulation of trypsinе-like activity (TLA) in the liver, and especially in the blood. At the resistance stage (48 hours after the stress) there is normalization of TLA in the blood and limitation of its growth in the liver. At the stage of exhaustion (an hour of stress during 10 days) the most significant increase of TLA in the liver and blood develops. Experimental hypothyroidism (25 mg/kg merkazolil within 20 days) per se causes a reduction of TLA, defines more pronounced stimulation of proteolysis in the alarm-stage, prevents its normalization at the resistance-stage, and promotes its excessive activation at the stage of exhaustion. Introduction of small doses of L-thyroxine (1.5-3.0 g/kg during 28 days) does not affect the system of proteolysis, limitis the increase of TLA at the alarm- and exhaustion stages, prevents its stimulation at the resistance-stage. The dependence of the changes in the proteases/inhibitors system under stress from the level of iodine-containing thyroid hormones in the blood is due to their influence on the activity of endogenous proteinase inhibitors (a1-antitrypsin and a2-macroglobulin) and on the permeability of lysosomes membranes.
Kampichler, Christian; Angeler, David G; Holmes, Richard T; Leito, Aivar; Svensson, Sören; van der Jeugd, Henk P; Wesołowski, Tomasz
2014-08-01
Numerous anthropogenic activities threaten the biodiversity found on earth. Because all ecological communities constantly experience temporal turnover due to natural processes, it is important to distinguish between change due to anthropogenic impact and the underlying natural rate of change. In this study, we used data sets on breeding bird communities that covered at least 20 consecutive years, from a variety of terrestrial ecosystems, to address two main questions. (1) How fast does the composition of bird communities change over time, and can we identify a baseline of natural change that distinguishes primeval systems from systems experiencing varying degrees of human impact? (2) How do patterns of temporal variation in composition vary among bird communities in ecosystems with different anthropogenic impacts? Time lag analysis (TLA) showed a pattern of increasing rate of temporal compositional change from large-scale primeval systems to disturbed and protected systems to distinctly successional systems. TLA slopes of <0.04 were typical for breeding bird communities with natural turnover, while communities subjected to anthropogenic impact were characterised by TLA slopes of >0.04. Most of the temporal variability of breeding bird communities was explained by slow changes occurring over decades, regardless of the intensity of human impact. In most of the time series, medium- and short-wave periodicity was not detected, with the exception of breeding bird communities subjected to periodic pulses (e.g. caterpillar outbreaks causing food resource peaks).
Melis, Anastasios; Mitra, Mautusi
2010-06-29
The invention provides method and compositions to minimize the chlorophyll antenna size of photosynthesis by decreasing TLA1 gene expression, thereby improving solar conversion efficiencies and photosynthetic productivity in plants, e.g., green microalgae, under bright sunlight conditions.
Teacher Language Awareness in Supervisory Feedback Cycles
ERIC Educational Resources Information Center
Lindahl, Kristen; Baecher, Laura
2016-01-01
This study investigates pre- and post-observation feedback provided to TESOL teacher candidates who are preparing to work in content-based instruction/content and language integrated learning contexts, extending the conceptualization of teacher language awareness (TLA) to candidate supervision. It examines the extent to which TLA is manifested by…
Stable CdS QDs with intense broadband photoluminescence and high quantum yields
NASA Astrophysics Data System (ADS)
Mandal, Abhijit; Saha, Jony; De, Goutam
2011-11-01
Aqueous synthesis of CdS quantum dots (QDs) using thiolactic acid (TLA) as a capping agent was reported. These QDs exhibited excellent colloidal and photostability over a span of 2 years and showed intense broadband and almost white photoluminescence suitable for solid state lighting devices. The photoluminescence (PL) property of the aqueous CdS QDs is optimized by adjusting various processing parameters. The highest quantum yield (QY) achieved for TLA capped CdS QDs of average size 3.5 nm was ˜50%. Luminescence lifetime measurements of CdS-TLA QDs indicated longer lifetimes and a larger contribution of the surface-related emission, indicating removal of quenching defects.
The Evolution of Teachers' Language Awareness
ERIC Educational Resources Information Center
Andrews, Stephen
2006-01-01
The paper focuses on the development of teacher thinking, specifically L2 teachers' subject-matter cognitions, i.e. their Teacher Language Awareness (TLA) (see e.g. Andrews 2001, 2003). The study examines the evolving TLA, as it relates to grammar, of three teachers, each a graduate with more than 10 years' experience of teaching English in Hong…
Teaching and Learning About Aging. Evaluation Report.
ERIC Educational Resources Information Center
Peters, Eileen
This evaluation study determined the extent to which teachers and students involved with the Teaching and Learning About Aging (TLA) project experienced cognitive growth and attitudinal change. The major purpose of the TLA project was to help students understand aging and related issues and to foster more positive attitudes toward aging and older…
Yahata, Yoshio; Masuda, Yoshiko; Komabayashi, Takashi
2017-12-01
The aim of this study was to compare the apical centring ability of incisal-shifted access (ISA) with that of traditional lingual access (TLA). Fifteen three-dimensional printed resin models were prepared from the computed tomography data for a human maxillary central incisor and divided into ISA (n = 7), TLA (n = 7) and control (n = 1) groups. After access preparation, these models were shaped to the working length using K-files up to #40, followed by step-back procedures. An apical portion of the model was removed at 0.5 mm coronal to the working length. Microscopic images of each cutting surface were taken to measure the preparation area and the distance of transportation. TLA created a larger preparation area than ISA (P < 0.05). The distance of transportation (mean ± standard deviation) was 0.4 ± 0.1 mm for ISA and 0.7 ± 0.1 mm for TLA (P < 0.05). Access cavity preparation has a significant effect on apical centring ability. ISA is beneficial to maintaining apical configuration. © 2017 Australian Society of Endodontology Inc.
Using Mobile TLA as a Logic for Dynamic I/O Automata
NASA Astrophysics Data System (ADS)
Kapus, Tatjana
Input/Output (I/O) automata and the Temporal Logic of Actions (TLA) are two well-known techniques for the specification and verification of concurrent systems. Over the past few years, they have been extended to the so-called dynamic I/O automata and, respectively, Mobile TLA (MTLA) in order to be more appropriate for mobile agent systems. Dynamic I/O automata is just a mathematical model, whereas MTLA is a logic with a formally defined language. In this paper, therefore, we investigate how MTLA could be used as a formal language for the specification of dynamic I/O automata. We do this by writing an MTLA specification of a travel agent system which has been specified semi-formally in the literature on that model. In this specification, we deal with always existing agents as well as with an initially unknown number of dynamically created agents, with mobile and non-mobile agents, with I/O-automata-style communication, and with the changing communication capabilities of mobile agents. We have previously written a TLA specification of this system. This paper shows that an MTLA specification of such a system can be more elegant and faithful to the dynamic I/O automata definition because the agent existence and location can be expressed directly by using agent and location names instead of special variables as in TLA. It also shows how the reuse of names for dynamically created and destroyed agents within the dynamic I/O automata framework can be specified in MTLA.
A multifractal approach to space-filling recovery for PET quantification.
Willaime, Julien M Y; Aboagye, Eric O; Tsoumpas, Charalampos; Turkheimer, Federico E
2014-11-01
A new image-based methodology is developed for estimating the apparent space-filling properties of an object of interest in PET imaging without need for a robust segmentation step and used to recover accurate estimates of total lesion activity (TLA). A multifractal approach and the fractal dimension are proposed to recover the apparent space-filling index of a lesion (tumor volume, TV) embedded in nonzero background. A practical implementation is proposed, and the index is subsequently used with mean standardized uptake value (SUV mean) to correct TLA estimates obtained from approximate lesion contours. The methodology is illustrated on fractal and synthetic objects contaminated by partial volume effects (PVEs), validated on realistic (18)F-fluorodeoxyglucose PET simulations and tested for its robustness using a clinical (18)F-fluorothymidine PET test-retest dataset. TLA estimates were stable for a range of resolutions typical in PET oncology (4-6 mm). By contrast, the space-filling index and intensity estimates were resolution dependent. TLA was generally recovered within 15% of ground truth on postfiltered PET images affected by PVEs. Volumes were recovered within 15% variability in the repeatability study. Results indicated that TLA is a more robust index than other traditional metrics such as SUV mean or TV measurements across imaging protocols. The fractal procedure reported here is proposed as a simple and effective computational alternative to existing methodologies which require the incorporation of image preprocessing steps (i.e., partial volume correction and automatic segmentation) prior to quantification.
[Surgical treatment of varicose vein using the tumescent technique of local anesthesia].
Bjelanović, Zoran; Leković, Ivan; Drasković, Miroljub; Misović, Sidor; Veljović, Milić
2011-02-01
Tumescent local anesthesia (TLA) is a technique for local and regional anesthesia of the skin and the subcutaneous tissue, using infiltration of large amounts of a diluted solution of local anesthetic. This technique is applied in plastic surgery, liposuction as well as in dermatology for the entire series of dermatocosmetic procedures. The purpose of this study was to determine efficiency of surgical treatment of varicose vein using TLA as an alternative method to a conventional treatment for varicose vein. Seventy-two patients with varicose vein were enrolled in the study. All of them were operated on applying TLA, from April 2008 to November 2009. TLA solution consisted of local anesthetics was used. TLA solutions used were: 1% prilocaine-chloride with adrenaline supplement, and 2% lidocaine-chloride and adrenaline in concentration of 0.1%-0.4%. Out of 72 patients, we stripped great saphenous vein from 60 patient and did varicectomy as well as ligation of insufficiently perforating veins. In 12 patients we did partial varicectomy and ligation of perforating veins. There were not any patients with the need for continued surgery, as well as bringing patient to the general anesthesia due to pain during the surgery. One patient came for postoperative opening wound in the groin, one for infection of the wound and one for the formation of seroma in the groin. There were not any allergic reactions or systemic complications in the operations as well as postoperative period. Postoperatively, all the patients were treated with compressive elastic bandage during the period of 6 weeks as well as anticoagulation prophylaxis in the duration of 5 days. Surgery of varicose veins with implementation of TLA is easy and safe method with very low percentage of complications and unwanted effects. It is a good alternative method to classic surgery of varicose veins. The economic aspect is a very important component because the cost of this method is significantly lower than that of a classical surgical treatment of varicose veins.
Identification of Behavior Based Safety by Using Traffic Light Analysis to Reduce Accidents
NASA Astrophysics Data System (ADS)
Mansur, A.; Nasution, M. I.
2016-01-01
This work present the safety assessment of a case study and describes an important area within the field production in oil and gas industry, namely behavior based safety (BBS). The company set a rigorous BBS and its intervention program that implemented and deployed continually. In this case, observers requested to have discussion and spread a number of determined questions related with work behavior to the workers during observation. Appraisal of Traffic Light Analysis (TLA) as one tools of risk assessment used to determine the estimated score of BBS questionnaire. Standardization of TLA appraisal in this study are based on Regulation of Minister of Labor and Occupational Safety and Health No:PER.05/MEN/1996. The result shown that there are some points under 84%, which categorized in yellow category and should corrected immediately by company to prevent existing bad behavior of workers. The application of BBS expected to increase the safety performance at work time-by-time and effective in reducing accidents.
MHD modelling of the heliospheric interface
NASA Astrophysics Data System (ADS)
Ratkiewicz, R.
The thin layer approximation (TLA) is used to ascertain the effect of the IMF on the heliospheric interface. The TLA approach can be used in considering properties of the solar wind termination shock, since by definition both curves are close to each other. Good agreement is obtained with previous predictions of the solar wind termination shock's shape and distance.
Rueda, Zulma Vanessa; López, Lucelly; Marín, Diana; Vélez, Lázaro A; Arbeláez, María Patricia
2015-04-01
To evaluate the concordance and safety of induced sputum (IS) and spontaneous sputum (SS), and estimate concordance and time to detection of M. tuberculosis between Lowenstein-Jensen (LJ), thin-layer agar (TLA), and the Mycobacteria Growth Indicator Tube system (MGIT). This was a cohort study. Prisoners with pulmonary tuberculosis (PTB) were followed for 2 years. At baseline and every follow-up visit, three sputum samples were taken on consecutive days (one IS and two SS) and adverse events occurring before, during, and 30 min after IS were registered. All sputum samples were stained with auramine and cultured in LJ, TLA (to test resistance), and MGIT. Five hundred eighty-six IS and 532 SS were performed on 64 PTB patients. Breathlessness (1.6%), cough (1.2%), hemoptysis (0.3%), and cyanosis (0.2%) were the only complications. Concordance between IS and SS was 0.78 (95% confidence interval 0.69-0.87); 11 positive cultures from IS samples were negative in SS, and 11 positive cultures from SS samples were negative in IS. One hundred seventy-eight cultures were positive by any technique: MGIT 95%, LJ 73%, and TLA 57%. Time to detection of M. tuberculosis in LJ, TLA, and MGIT was 31, 18, and 11 days, respectively. The IS procedure is safe in prisons. The MGIT system is better and faster than LJ and TLA in the diagnosis of M. tuberculosis. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
The Outcome of Primary Subglandular Breast Augmentation Using Tumescent Local Anesthesia.
Rusciani, Antonio; Pietramaggiori, Giorgio; Troccola, Antonietta; Santoprete, Stefano; Rotondo, Antonio; Curinga, Giuseppe
2016-01-01
Tumescent local anesthesia (TLA) technique to obtain regional anesthesia and vasoconstriction of the skin and subcutaneous tissues is routinely adopted for several plastic surgery procedures. Here, we describe the use of TLA in primary subglandular breast augmentation. This series evaluates advantages and disadvantages of TLA in elective augmentation breast surgery as well as patients' response to this procedure. Between December 2008 and November 2011, 150 patients underwent bilateral primary subglandular breast augmentation under TLA and conscious sedation in the presence of a board-certified anesthesiologist. Midazolam 0.05 mg/kg IV and ranitidine 100 mg IV were given as premedication. Tumescent local anesthesia was composed of 25 mL of lidocaine 2%, 8 mEq of sodium bicarbonate, and 1 mL of epinephrine (1 mg/1 mL) in 1000 mL of 0.9% NS. The solution was delivered between the pectoral fascia and the mammary gland via a spinal needle. After infiltration, 45 minutes were allowed before surgery for local anesthetic effects to take place. The mean age of the patients was 34.3 years. The average amount of tumescent solution infiltrated was 1150 mL, with a maximal dose of 17 mg/kg of lidocaine used. Operating time was 45 minutes and recovery room time averaged 125 minutes. Minor complications were found in a total of 9 (5.3%) patients, with no main surgery-related complications such as hematoma or seroma formation. Breast augmentation under TLA and conscious sedation proved to be safe in the presence of a board-certified anesthesiologist and when performed with meticulous surgical technique.
Routes for virtually guided endoscopic liver resection of subdiaphragmatic liver tumors.
Aoki, Takeshi; Murakami, Masahiko; Fujimori, Akira; Koizumi, Tomotake; Enami, Yuta; Kusano, Tomokazu; Matsuda, Kazuhiro; Yamada, Kosuke; Nogaki, Koji; Wada, Yusuke; Hakozaki, Tomoki; Goto, Satoru; Watanabe, Makoto; Otsuka, Koji
2016-03-01
Laparoscopic and thoracoscopic/laparoscopic hepatectomy is a safe procedure that has potential advantages over open surgery. However, deeply positioned liver tumors require expert laparoscopic and thoracoscopic/laparoscopic hepatectomy techniques. Using simulated preoperative three-dimensional virtual endoscopy (P3DVE) guidance, we demonstrate herein that a thoracoscopic approach (TA), thoracoscopic-laparoscopic approach (TLA), and laparoscopic approach (LA) are all feasible and safe routes for performing pure laparoscopic and thoracoscopic/laparoscopic resection of liver tumors located in the 4a, 7, and 8 liver subdiaphragmatic areas. Thirty-eight patients underwent laparoscopic and thoracoscopic/laparoscopic partial liver resection (TA 13 cases, TLA two cases, and LA 23 cases) of the subdiaphragmatic area at Showa University Hospital. All surgical approaches were preoperatively determined based on preoperative 3D virtual endoscopic simulation (P3DVES) visualization and findings using the image processing software SYNAPSE VINCENT(®). Laparoscopic and thoracoscopic/laparoscopic liver resection was successfully performed for all cases under P3DVE instruction. The mean operative times using TA, TLA, and LA approaches were 193, 185, and 190 min, respectively. Mean blood loss during TA, TLA, and LA was 179, 138, and 73 g, respectively. No patients required conversion to open surgery, and there were no deaths, although there were three cases of Clavien-Dindo grade I in TA along with three cases of grade I and one case of grade II in LA. TA, TLA, and LA routes performed under P3DVE instruction are feasible and safe to perform for pure laparoscopic and thoracoscopic/laparoscopic liver resection in selected patients with lesions located in the hepatic subdiaphragmatic area.
A multifractal approach to space-filling recovery for PET quantification
DOE Office of Scientific and Technical Information (OSTI.GOV)
Willaime, Julien M. Y., E-mail: julien.willaime@siemens.com; Aboagye, Eric O.; Tsoumpas, Charalampos
2014-11-01
Purpose: A new image-based methodology is developed for estimating the apparent space-filling properties of an object of interest in PET imaging without need for a robust segmentation step and used to recover accurate estimates of total lesion activity (TLA). Methods: A multifractal approach and the fractal dimension are proposed to recover the apparent space-filling index of a lesion (tumor volume, TV) embedded in nonzero background. A practical implementation is proposed, and the index is subsequently used with mean standardized uptake value (SUV {sub mean}) to correct TLA estimates obtained from approximate lesion contours. The methodology is illustrated on fractal andmore » synthetic objects contaminated by partial volume effects (PVEs), validated on realistic {sup 18}F-fluorodeoxyglucose PET simulations and tested for its robustness using a clinical {sup 18}F-fluorothymidine PET test–retest dataset. Results: TLA estimates were stable for a range of resolutions typical in PET oncology (4–6 mm). By contrast, the space-filling index and intensity estimates were resolution dependent. TLA was generally recovered within 15% of ground truth on postfiltered PET images affected by PVEs. Volumes were recovered within 15% variability in the repeatability study. Results indicated that TLA is a more robust index than other traditional metrics such as SUV {sub mean} or TV measurements across imaging protocols. Conclusions: The fractal procedure reported here is proposed as a simple and effective computational alternative to existing methodologies which require the incorporation of image preprocessing steps (i.e., partial volume correction and automatic segmentation) prior to quantification.« less
A Case Study of Developing Student-Teachers' Language Awareness through Online Discussion Forums
ERIC Educational Resources Information Center
Mok, Jane
2013-01-01
A major challenge for language teacher educators working in the area of teacher language awareness (TLA) is to develop pedagogical approaches that will go beyond merely enhancing L2 teachers' knowledge about language by enabling them to make the bridge between the declarative and procedural dimensions of TLA. This paper sets out to investigate the…
Wear measurement of the cutting edge of superhard turning tools using TLA technique
NASA Astrophysics Data System (ADS)
Vasváry, L.; Ditrói, F.; Takács, S.; Szabó, Z.; Szűcs, J.; Kundrák, J.; Mahunka, I.
1994-03-01
Wear measurement on superhard boron nitride and artificial diamond turning tools was performed using thin layer activation (TLA) technique. The samples were irradiated in two different geometries to improve the sensitivity of the method and change the region of wear to be investigated. The most proper irradiation parameters and nuclear reactions were investigated for both kind of tools.
Chiang, Po Hui; Yu, Cheng Jen; Lee, Wei Ching; Wang, Hung Jen; Hsu, Wu Chi
2015-01-01
There is a lack of data regarding the appropriateness of transperitoneal and retroperitoneal approaches for right-sided laparoscopic adrenalectomy. The aim of this study was to determine whether there is any difference between right-sided transperitoneal laparoscopic adrenalectomy (TLA) and retroperitoneal laparoscopic adrenalectomy (RLA). Our surgery database was reviewed to identify patients who underwent right-sided laparoscopic adrenalectomy with a retroperitoneal or transperitoneal approach since 2000. Fifty-five patients were enrolled (31 RLA and 24 TLA). Patient characteristics, as well as operative and perioperative details, were compared between the two groups. There was no difference in patient characteristics between the groups. There was a statistically significant difference (p=0.02) in blood loss (31.7±16.4 vs. 56.9±65.5 ml) between RLA and TLA when the patient's BMI was >26. There was no significant difference in operative time, conversion to open surgery, length of hospitalization, or time to oral intake between the groups. Right-sided laparoscopic adrenalectomy can be performed safely and effectively via either RLA or TLA. Surgeons can adopt either approach with confidence depending on their preference if they are familiar with that approach. © 2015 S. Karger AG, Basel.
Zhuo, Xunhui; Sun, Hongchao; Zhang, Zhi; Luo, Jiaqing; Shan, Ying; Du, Aifang
2017-06-01
Serologic tests are widely accepted and applied as means to detect anti- Toxoplasma gondii immunoglobulin G antibodies. In this study, recombinant matrix antigen (rMAG1) was induced by isopropyl-β-d-thiogalactoside and purified by nickel-nitrilotriacetic acid purification system. We then developed and optimized an indirect enzyme-linked immunosorbent assay (ELISA) through checkerboard assays using serial dilutions of antigens and sera to assess the potential use of rMAG1 in serologic detection of T. gondii infection in dogs. Serum samples from 93 domestic dogs were analyzed by western blot and rMAG1-ELISA. The results were compared with those obtained from an ELISA with the soluble Toxoplasma lysate antigens (TLA). We found that although yielding an excellent agreement (96.7%) with western blot data (κ = 0.9659), rMAG1-ELISA produced higher sensitivity (93.9% vs. 87.8%) and specificity (98.3% vs. 96.7%) than TLA-ELISA. In addition, receiver operating characteristic analysis also revealed that rMAG1-ELISA is in more agreement with western blot (area under the curve [AUC] = 0.985) relative to TLA-ELISA (AUC = 0.955). These results indicated that the rMAG1-ELISA established in this study provides a promising and reliable tool for serologic detection of T. gondii infection in dogs.
Gore, C; Gore, R B; Fontanella, S; Haider, S; Custovic, A
2018-05-01
Children with severe, persistent atopic eczema (AE) have limited treatment options, often requiring systemic immunosuppression. To evaluate the effect of the temperature-controlled laminar airflow (TLA) treatment in children/adolescents with severe AE. We recruited 15 children aged 2-16 years with long-standing, severe AE and sensitization to ≥1 perennial inhalant allergen. Run-in period of 6-10 weeks (3 visits) was followed by 12-month treatment with overnight TLA (Airsonett ® , Sweden). The primary outcome was eczema severity (SCORAD-Index and Investigator Global Assessment-IGA). Secondary outcomes included child/family dermatology quality of life and family impact questionnaires (CDQLI, FDQLI, DFI), patient-oriented eczema measure (POEM), medication requirements and healthcare contacts. The study is registered as ISRCTN65865773. There was a significant reduction in AE severity ascertained by SCORAD and IGA during the 12-month intervention period (P < .001). SCORAD was reduced from a median of 34.9 [interquartile range 28.75-45.15] at Baseline to 17.2 [12.95-32.3] at the final visit, and IGA improved significantly from 4 [3-4] to 2 [1-3]. We observed a significant improvement in FDQLI (16.0 [12.25-19.0] to 12 [8-18], P = .023) and DFI (P = .011), but not CDQLI or POEM. Compared to 6-month period prior to enrolment, there was a significant reduction at six months after the start of the intervention in potent topical corticosteroids (P = .033). The exploratory cluster analysis revealed two strongly divergent patterns of response, with 9 patients classified as responders, and 6 as non-responders. Addition of TLA device to standard pharmacological treatment may be an effective add-on to the management of difficult-to-control AE. © 2018 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Asami, Koji
2010-12-01
There are a few concerns in dielectric modeling of biological cells by the finite-element method (FEM) to simulate their dielectric spectra. Cells possess thin plasma membranes and membrane-bound intracellular organelles, requiring extra fine meshes and considerable computational tasks in the simulation. To solve the problems, the “thin-layer” approximation (TLA) and the “effective medium” approximation (EMA) were adopted. TLA deals with the membrane as an interface of the specific membrane impedance, and therefore it is not necessary to divide the membrane region. EMA regards the composite cytoplasm as an effective homogeneous phase whose dielectric properties are calculated separately. It was proved that TLA and EMA were both useful for greatly reducing computational tasks while accurately coinciding with analytical solutions.
Nursing workload in the acute-care setting: A concept analysis of nursing workload.
Swiger, Pauline A; Vance, David E; Patrician, Patricia A
2016-01-01
A pressing need in the field of nursing is the identification of optimal staffing levels to ensure patient safety. Effective staffing requires comprehensive measurement of nursing workload to determine staffing needs. Issues surrounding nursing workload are complex, and the volume of workload is growing; however, many workload systems do not consider the numerous workload factors that impact nursing today. The purpose of this concept analysis was to better understand and define nursing workload as it relates to the acute-care setting. Rogers' evolutionary method was used for this literature-based concept analysis. Nursing workload is influenced by more than patient care. The proposed definition of nursing workload may help leaders identify workload that is unnoticed and unmeasured. These findings could help leaders consider and identify workload that is unnecessary, redundant, or more appropriate for assignment to other members of the health care team. Published by Elsevier Inc.
ERIC Educational Resources Information Center
Moor, Helen; Lamont, Emily; Lord, Pippa; Gulliver, Caroline
2006-01-01
This research sets out key findings from an evaluation of Phases 1 and 2 of the pilot Teacher Learning Academy (TLA). The pilot TLA was established by the General Teaching Council for England (GTC) to provide professional and public recognition for teacher learning and development work. The Academy offers the opportunity for the learning that…
ERIC Educational Resources Information Center
Ashwin, Paul
2008-01-01
This paper examines research into teaching, learning and assessment (TLA) in higher education in terms of structure and agency. It argues that although issues of structure and agency are seen as crucial in social theory, they are very little discussed in research into TLA in higher education and that a consideration of structure and agency raises…
Chung, Hee-Jung; Song, Yoon Kyung; Hwang, Sang-Hyun; Lee, Do Hoon; Sugiura, Tetsuro
2018-02-25
Use of total laboratory automation (TLA) system has expanded to microbiology and hemostasis and upgraded to second and third generations. We herein report the first successful upgrades and fusion of different versions of the TLA system, thus improving laboratory turnaround time (TAT). A 21-day schedule was planned from the time of pre-meeting to installation and clinical sample application. We analyzed the monthly TAT in each menu, distribution of the "out of range for acceptable TAT" samples, and "prolonged time out of acceptable TAT," before and after the upgrade and fusion. We installed and customized hardware, middleware, and software. The one-way CliniLog 2.0 version track, 50.0-m long, was changed to a 23.2-m long one-way 2.0 version and an 18.7-m long two-way 4.0 version. The monthly TAT in the outpatient samples, before and after upgrading the TLA system, were uniformly satisfactory in the chemistry and viral marker menus. However, in the tumor marker menu, the target TAT (98.0% of samples ≤60 minutes) was not satisfied during the familiarization period. There was no significant difference in the proportion of "out of acceptable TAT" samples, before and after the TLA system upgrades (7.4‰ and 8.5‰). However, the mean "prolonged time out of acceptable TAT" in the chemistry samples was significantly shortened to 17.4 (±24.0) minutes after the fusion, from 34.5 (±43.4) minutes. Despite experimental challenges, a fusion of the TLA system shortened the "prolonged time out of acceptable TAT," indicating a distribution change in overall TAT. © 2018 Wiley Periodicals, Inc.
Lairmore, Terry C; Folek, Jessica; Govednik, Cara M; Snyder, Samuel K
2016-07-01
Minimally invasive adrenalectomy is commonly performed by either a transperitoneal laparoscopic (TLA) or posterior retroperitoneoscopic (PRA) approach. Our group described the technique for robot-assisted PRA (RAPRA) in 2010. Few studies are available that directly compare outcomes between the available operative approaches. We reviewed our results for minimally invasive adrenalectomy using the three different approaches over a 10-year period. Between January 2005 and April 2015, 160 minimally invasive adrenalectomies were performed. Clinicopathologic data were prospectively collected and retrospectively analyzed. The primary endpoints evaluated were operative time, blood loss, length of stay (LOS), and morbidity. The study included 67 TLA, 76 PRA, and 17 RAPRA procedures. Tumor size for PRA/RAPRA was smaller than for patients undergoing TLA (2.38 vs 3.6 cm, p ≤ 0.0001). Procedure time was shorter for PRA versus TLA (133.3 vs 152.8 min, p = 0.0381), as was LOS (1.85 vs 2.82 days, p = 0.0145). Procedure time was longer in RAPRA versus TLA/PRA (177 vs 153/133 min, p = 0.008), but LOS was significantly decreased (1.53 vs 2.82/1.85 days, p = 0.004). Minimally invasive adrenalectomy is associated with expected excellent outcomes regardless of approach. In our series, the posterior approach is associated with decreased operative time and LOS. Robotic technology provides potential advantages for the surgeon at the expense of more complex setup requirements and costs. Further study is required to demonstrate clear benefit of one surgical approach. Utilization of the entire spectrum of available operative techniques can allow for selection of the optimal approach based on individual patient factors.
de Gois Macêdo, Bruna; Peixoto, Rephany Fonseca; Maciel, Bruna Leal Lima; de Assis Silva Gomes, Juliana; de Lourdes Assunção Araújo de Azevedo, Fátima; Veras, Robson Cavalcanti; de Medeiros, Isac Almeida; de Lima Grisi, Teresa Cristina Soares; de Araújo, Demétrius Antônio Machado; Amaral, Ian Porto Gurgel do; de Souza Lima, Tatjana Keesen
2018-04-27
Although the semi-invariant natural killer T cells (iNKT) are a small subpopulation of cells in the peripheral blood, they are presumed to play a role in early stages of infection against various pathogens, including protozoa. This work investigates the activation status and cytokine profile of iNKT cells during human Leishmania infantum and Leishmania braziliensis infection. We studied iNKT cells in symptomatic active visceral patients (AVL) (n=8), symptomatic active cutaneous patients (ACL) (n=13), negative endemic controls (NEC) (n=6) and non-endemic controls (NonEC) (n=6), with and without Total Leishmania antigen stimulus (TLA). The number of iNKT cells in the peripheral blood of ACL and AVL patients unaltered in relation to control groups. Moreover, the iNKT cells from ACL showed a hyperactivation profile compared to AVL patients. Additionally, TLA induced IFN-gamma production in iNKT cells from ACL patients, while in iNKT of AVL patients, TLA induced a decrease of this cytokine. Higher IL-17 and IL-10 production by iNKT cells from ACL patients were also observed compared to all other groups. There were no changes in IL-10 iNKT producing cells in AVL after TLA stimulation. However, TLA induced increase of IL-10 in iNKT cells in ACL patients. These findings suggest that although iNKT cells showed distinct profiles in ACL and AVL patients, they play a dual role in immune modulation in both Leishmania infections. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Defidio, Lorenzo; De Dominicis, Mauro; Di Gianfrancesco, Luca; Fuchs, Gerhard; Patel, Anup
2011-09-01
Thulium laser ablation (TLA) outcomes with blinded performance evaluation after retrograde intra-renal surgical (RIRS) treatment of upper urinary tract transitional cell carcinomas (UUT-TCC). A UUT-TCC patient cohort undergoing RIRS-TLA by an international endoscopic surgical collaboration in a European center (April 2005-July 2009), underwent outcomes evaluation. All 4 surgeons were blinded and independently scored both TLA and Holmium:YAG laser ablation performance aspects annually using a Likert scoring system (0-10). All patients (n = 59, median age 66 years, 9 with solitary kidney) had complete UUT inspection. Presenting lesion(s) were intra-renal (n = 30, 51%), ureteral (n = 13, 22%), and combined (n = 16, 27%). Single-stage TLA sufficed in 81.4% (tumors < 1.5 cm). Significant recurrence free survival differences occurred according to primary tumor size >/< 1.5 cm and multi-focality, but location made no difference. Median Likert scores were i) fiber-tip stability --5.5/8.75, p = 0.016; ii) reduced bleeding--5/8.5, p = 0.004; iii)fiber-tip precision--5.5/8.5, p = 0.003; iv) mucosal perforation reduction--3.5/7.5, p = 0.001; v) ablation efficiency tumors < 1.5 cm--6/9, p = 0.017; tumors > 1.5 cm--6.75/6.75, p = 1, and vi) overall efficiency--6/7.5, p = 0.09, for Holmium:YAG and TLA, respectively. The Thulium laser delivered non-inferior recurrence free survival to RIRS-UUT-TCC Holmium:YAG laser ablation, but better median parameter performance scores in fiber-tip stability, precision, reduced bleeding and mucosal perforation reduction in expert ratings. Despite improved photothermal coagulation, and endo-visualization for tumors < 1.5 cm, both ablation and overall efficiency remained challenging for larger tumors with both existing laser technologies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Timmins, T.H.; Mason, E.A.
1963-04-01
An investigation of the solvent extraction characteristics of nitric acid and the nitrato complexes of nitrosylruthenium was conducted, using alkyl amines as extractants. The alkyl amines used were a primary amine Primene JMT, a tertiary amine trilaurylamine (TLA), and a quaternary amine Aliquat 336. The organic phase concentrations of HNO/sub 3/ resulting during extraction by alkyl amines were found to correlate well on the basis of the undissociated aqueous HNO/ sub 3/ activity for both salted (NaNO/sub 3/) and unsalted aqueous phases. The distribution ratios for Ru extraction showed better correlation on this basis than on the basis of aqueousmore » phase nitrate and nitric acid. The order of decreasing Ru extraction at low HNO/sub 3/ concentration (2N) was found to be Aliquat 336, TLA, and Primene JMT. At high HNO/sub 3/ concentration (9N). Primene JMT had the highest Ru extractability. Hapid dilution experiments were utilized to determine the number and aqueous phase concentrations of the extractable species of Ru, and the amine partition coefficients for the species. It was found that two Ru species are extractable, and the more extractable species is present in the aqueous phase at lower concentration than the less extractable species. The mole fractions of both species were found to increase with increasing HNO/sub 3/ concentration. The TLA partition coefficients for the extractable species were found to decrease with increasing HNO/sub 3/ concentration. The quaternary amine, Aliquat 336, was found to have partition coefficients an order of magnitude greater than the tertiary amine, TLA. Equations for the mole fractions and TLA partition coefficients in the region of HNO/sub 3/ concentration investigated were developed. (auth)« less
Controlling resonant photonic transport along optical waveguides by two-level atoms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yan Conghua; College of Physics and Electronic Engineering, Sichuan Normal University, Chengdu 610068; Wei Lianfu
2011-10-15
Recent works [Shen et al., Phys. Rev. Lett. 95, 213001 (2005); Zhou et al., Phys. Rev. Lett. 101, 100501 (2008)] showed that the incident photons cannot transmit along an optical waveguide containing a resonant two-level atom (TLA). Here we propose an approach to overcome such a difficulty by using asymmetric couplings between the photons and a TLA. Our numerical results show that the transmission spectrum of the photon depends on both the frequency of the incident photons and the photon-TLA couplings. Consequently, this system can serve as a controllable photon attenuator, by which the transmission probability of the resonantly incidentmore » photons can be changed from 0% to 100%. A possible application to explain the recent experimental observations [Astafiev et al., Science 327, 840 (2010)] is also discussed.« less
ERIC Educational Resources Information Center
Mathieson, Susan
2012-01-01
There is a growing awareness of the need to move beyond generic approaches to teaching, learning and assessment (TLA) to consider the importance of context in shaping TLA practices. However, efforts to engage with context have focused primarily on disciplinary epistemologies and in particular the differences between hard, soft, pure and applied…
Rutting and Fatigue Cracking Resistance of Waste Cooking Oil Modified Trinidad Asphaltic Materials.
Maharaj, Rean; Ramjattan-Harry, Vitra; Mohamed, Nazim
2015-01-01
The influence of waste cooking oil (WCO) on the performance characteristics of asphaltic materials indigenous to Trinidad, namely, Trinidad Lake Asphalt (TLA), Trinidad Petroleum Bitumen (TPB), and TLA : TPB (50 : 50) blend, was investigated to deduce the applicability of the WCO as a performance enhancer for the base asphalt. The rheological properties of complex modulus (G (∗) ) and phase angle (δ) were measured for modified base asphalt blends containing up to 10% WCO. The results of rheology studies demonstrated that the incremental addition of WCO to the three parent binders resulted in incremental decreases in the rutting resistance (decrease in G (∗) /sinδ values) and increases in the fatigue cracking resistance (decrease in G (∗) sinδ value). The fatigue cracking resistance and rutting resistance for the TLA : TPB (50 : 50) blends were between those of the blends containing pure TLA and TPB. As operating temperature increased, an increase in the resistance to fatigue cracking and a decrease in the rutting resistance were observed for all of the WCO modified asphaltic blends. This study demonstrated the capability to create customized asphalt-WCO blends to suit special applications and highlights the potential for WCO to be used as an environmentally attractive option for improving the use of Trinidad asphaltic materials.
Caroli, Paola; De Giorgi, Ugo; Scarpi, Emanuela; Fantini, Lorenzo; Moretti, Andrea; Galassi, Riccardo; Celli, Monica; Conteduca, Vincenza; Rossi, Lorena; Bianchi, Emanuela; Paganelli, Giovanni; Matteucci, Federica
2018-03-01
The role of 18F-choline positron emission tomography/computed tomography (FCH-PET/CT) in patients with metastatic castration-resistant prostate cancer (mCRPC) has been firmly established in recent years. We analyzed the prognostic value of functional parameters such as mean standardized uptake volume (SUVmean), maximum standardized uptake volume (SUVmax), metabolic total volume (MTV; the volume of interest consisting of all spatially connected voxels within a fixed threshold of 40% of the SUVmax), and total lesion activity (TLA: the product of MTV and mean standardized uptake value) estimated with FCH-PET/CT in mCRPC patients in progression after docetaxel and treated with new antiandrogen receptor therapies, abiraterone or enzalutamide. We retrospectively studied 94 mCRPC patients, mean age 74 years (range 42-90), previously treated with docetaxel who were treated with either abiraterone (n = 52) or enzalutamide (n = 42). An FCH-PET/CT was performed at baseline, and patients were evaluated on a monthly basis for serological PSA response and every 3 months for radiological response. We measured MTV, SUVmean, SUVmax and TLA for each lesion and analyzed the sum of MTV (SMTV), SUVmean (SSUVmean), SUVmax (SSUVmax) and TLA (STLA) values for a maximum of 20 lesions. Univariate analysis was used to correlate these data with PFS and OS. We observed a median SMTV of 130 cm 3 , median SSUVmax of 106.5 and a median STLA of 495,070. All of these parameters were significant for PFS and OS in univariate analysis, while only STLA was significant for PFS and OS in multivariate analysis after adjusting for lesion and age (p < 0.0001 and p = 0.001, respectively). Baseline PSA values maintained a certain reliability for OS (p = 0.034). Semiquantitative parameters of FCH-PET/CT play a prognostic role in mCRCP patients treated with abiraterone or enzalutamide.
Temporal analysis of remotely sensed turbidity in a coastal archipelago
NASA Astrophysics Data System (ADS)
Suominen, Tapio; Tolvanen, Harri
2016-07-01
A topographically fragmental archipelago with dynamic waters set the preconditions for assessing coherent remotely sensed information. We generated a turbidity dataset for an archipelago coast in the Baltic Sea from MERIS data (FSG L1b), using CoastColour L1P, L2R and L2W processors. We excluded land and mixed pixels by masking the imagery with accurate (1:10 000) shoreline data. Using temporal linear averaging (TLA), we produced satellite-imagery datasets applicable to temporal composites for the summer seasons of three years. The turbidity assessments and temporally averaged data were compared to in situ observations obtained with coastal monitoring programs. The ability of TLA to estimate missing pixel values was further assessed by cross-validation with the leave-one-out method. The correspondence between L2W turbidity and in situ observations was good (r = 0.89), and even after applying TLA the correspondence remained acceptable (r = 0.78). The datasets revealed spatially divergent temporal water characteristics, which may be relevant to the management, design of monitoring and habitat models. Monitoring observations may be spatially biased if the temporal succession of water properties is not taken into account in coastal areas with anisotropic dispersion of waters and asynchronous annual cycles. Accordingly, areas of varying turbidity may offer a different habitat for aquatic biota than areas of static turbidity, even though they may appear similar if water properties are measured for short annual periods.
Pilot Workload and Speech Analysis: A Preliminary Investigation
NASA Technical Reports Server (NTRS)
Bittner, Rachel M.; Begault, Durand R.; Christopher, Bonny R.
2013-01-01
Prior research has questioned the effectiveness of speech analysis to measure the stress, workload, truthfulness, or emotional state of a talker. The question remains regarding the utility of speech analysis for restricted vocabularies such as those used in aviation communications. A part-task experiment was conducted in which participants performed Air Traffic Control read-backs in different workload environments. Participant's subjective workload and the speech qualities of fundamental frequency (F0) and articulation rate were evaluated. A significant increase in subjective workload rating was found for high workload segments. F0 was found to be significantly higher during high workload while articulation rates were found to be significantly slower. No correlation was found to exist between subjective workload and F0 or articulation rate.
The workload analysis in welding workshop
NASA Astrophysics Data System (ADS)
Wahyuni, D.; Budiman, I.; Tryana Sembiring, M.; Sitorus, E.; Nasution, H.
2018-03-01
This research was conducted in welding workshop which produces doors, fences, canopies, etc., according to customer’s order. The symptoms of excessive workload were seen from the fact of employees complaint, requisition for additional employees, the lateness of completion time (there were 11 times of lateness from 28 orders, and 7 customers gave complaints). The top management of the workshop assumes that employees’ workload was still a tolerable limit. Therefore, it was required workload analysis to determine the number of employees required. The Workload was measured by using a physiological method and workload analysis. The result of this research can be utilized by the workshop for a better workload management.
AMINE EXTRACTION OF PLUTONIUM FROM NITRIC ACID SOLUTIONS LOADING AND STRIPPING EXPERIMENTS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilson, A.S.
1961-01-19
Information is presented on a suitable amine processing system for plutonium nitrate. Experiments with concentrated plutonium nitrate solutions show that trilaurylamine (TLA) - xylene solvent systems did not form a second organic phase. Experiments are also reported with tri-noctylamine (TnOA)-xylene and TLA-Amsco - octyl alcohol. Two organic phases appear in both these systems at high plutonium nitrate concentrations. Data are tabulated from loading and stripping experiments. (J.R.D.)
Case report : tuberculosis liver abscess in male alcoholism patient
NASA Astrophysics Data System (ADS)
Siahaan, W. P.; Ginting, F.
2018-03-01
A liver abscess often occurs in low-middle income countries such as Indonesia. Two most common liver abscesses are amoebic and pyogenic liver abscess. Data that reported tuberculosis liver abscess (TLA) is extremely rare. A diagnostic criterion for tuberculosis liver abscess is rare and remains unclear. A 52-year-old man developed a TLA which was not associated with any pulmonary or gastrointestinal tract foci of tuberculosis. An ultrasonogram and abdominal scan showed an abscess in the right lobe. We performed paracentesis, and the pus from the lesion was positive tubercular bacilli on acid-fast bacilli staining. The patient was started on systemic antitubercular therapy to which he responded favorably. This report emphasizes the fact that, although a TLA is a very rare entity, it should be included in the differential diagnosis of liver abscess especially in Indonesia where the prevalence of tuberculosis is extremely high.
The optimization of total laboratory automation by simulation of a pull-strategy.
Yang, Taho; Wang, Teng-Kuan; Li, Vincent C; Su, Chia-Lo
2015-01-01
Laboratory results are essential for physicians to diagnose medical conditions. Because of the critical role of medical laboratories, an increasing number of hospitals use total laboratory automation (TLA) to improve laboratory performance. Although the benefits of TLA are well documented, systems occasionally become congested, particularly when hospitals face peak demand. This study optimizes TLA operations. Firstly, value stream mapping (VSM) is used to identify the non-value-added time. Subsequently, batch processing control and parallel scheduling rules are devised and a pull mechanism that comprises a constant work-in-process (CONWIP) is proposed. Simulation optimization is then used to optimize the design parameters and to ensure a small inventory and a shorter average cycle time (CT). For empirical illustration, this approach is applied to a real case. The proposed methodology significantly improves the efficiency of laboratory work and leads to a reduction in patient waiting times and increased service level.
Controlling resonant photonic transport along optical waveguides by two-level atoms
NASA Astrophysics Data System (ADS)
Yan, Cong-Hua; Wei, Lian-Fu; Jia, Wen-Zhi; Shen, Jung-Tsung
2011-10-01
Recent works [Shen , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.95.213001 95, 213001 (2005); Zhou , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.101.100501 101, 100501 (2008)] showed that the incident photons cannot transmit along an optical waveguide containing a resonant two-level atom (TLA). Here we propose an approach to overcome such a difficulty by using asymmetric couplings between the photons and a TLA. Our numerical results show that the transmission spectrum of the photon depends on both the frequency of the incident photons and the photon-TLA couplings. Consequently, this system can serve as a controllable photon attenuator, by which the transmission probability of the resonantly incident photons can be changed from 0% to 100%. A possible application to explain the recent experimental observations [Astafiev , ScienceSCIEAS0036-807510.1126/science.1181918 327, 840 (2010)] is also discussed.
ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE-EVENT SIMULATION
2016-03-24
ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION...in the United States. AFIT-ENV-MS-16-M-166 ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION...UNLIMITED. AFIT-ENV-MS-16-M-166 ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION Erich W
The PlusCal Algorithm Language
NASA Astrophysics Data System (ADS)
Lamport, Leslie
Algorithms are different from programs and should not be described with programming languages. The only simple alternative to programming languages has been pseudo-code. PlusCal is an algorithm language that can be used right now to replace pseudo-code, for both sequential and concurrent algorithms. It is based on the TLA + specification language, and a PlusCal algorithm is automatically translated to a TLA + specification that can be checked with the TLC model checker and reasoned about formally.
Fractional conversion of microalgae from water blooms.
Zhou, Yingdong; Li, Linling; Zhang, Rui; Hu, Changwei
2017-09-21
Fractional conversion of natural algae cyanobacteria from Taihu Lake was conducted. The raw Taihu Lake algae (TLA) and pretreated samples were pyrolyzed at 290 °C and 450 °C according to the TGA results. Extraction of lipids or saccharides from the TLA was performed as a pretreatment to obtain lipid extracted algae (LEA) or saccharide extracted algae (SEA). The total yields of bio-oil from fractional pyrolysis were 40.9 wt% from TLA, 42.3 wt% from LEA, and 48.5 wt% from SEA. From TLA, the major components of the bio-oil were fatty acids, amides and hydrocarbons (heptadecane) at 290 °C whereas those at 450 °C were phenols and C 10 -C 15 hydrocarbons. Following the lipid extraction, acids, amides and indoles accounted for a large proportion at 290 °C, while the main products obtained at 450 °C were phenols, indoles and pyrroles. It is worth mentioning that the yield of bio-oil from the LEA had increased, and the composition of the bio-oil was simplified. Moreover, the average molecular weight of the bio-oil obtained from LEA had decreased. Interestingly, the extraction of saccharides inhibited pyrolysis of the lipids, so the distribution of the bio-oil from SEA changed only a little. Fractional pyrolysis of pretreated microalgae not only increased the bio-oil yield but also improved the quality of the bio-oil.
Drinić, Mirjana; Wagner, Angelika; Sarate, Priya; Zwicker, Christian; Korb, Elke; Loupal, Gerhard; Peschke, Roman; Joachim, Anja; Wiedermann, Ursula; Schabussova, Irma
2017-11-09
Epidemiological and experimental studies have shown an inverse relationship between infections with certain parasites and a reduced incidence of allergic diseases. We and others have shown that infection with Toxoplasma gondii prevents the development of allergy in mice. To establish whether this beneficial effect could be recapitulated by soluble products of this parasite, we tested an extract derived from T. gondii tachyzoites. Immunization of BALB/c mice with tachyzoites lysate antigen (TLA) elicited mixed Th1/Th2 responses. When TLA was applied together with the sensitizing ovalbumin (OVA), the development of allergic airway inflammation was reduced, with decreased airway hyperresponsiveness associated with reduced peribronchial and perivascular cellular infiltration, reduced production of OVA-specific Th2 cytokines in lungs and spleens and reduced levels of serum OVA-specific IgG1 as well as IgE-dependent basophil degranulation. Of note, TLA retained its immunomodulatory properties, inducing high levels of IL-6, TNFα, IL-10 and IL-12p70 in bone marrow-derived dendritic cells after heat-inactivation or proteinase K-treatment for disruption of proteins, but not after sodium metaperiodate-treatment that degrades carbohydrate structures, suggesting that carbohydrates may play a role in immunomodulatory properties of TLA. Here we show that extracts derived from parasites may replicate the benefits of parasitic infection, offering new therapies for immune-mediated disorders.
Kumar, K; Sharma, D
2018-04-01
Multiple landmarks including the transepicondylar axis (TEA), posterior condylar axis (PCA) and anterior trochlear line (TL) have been used to set up the femoral component rotation, but each is faced with its own practical obstacle that limits its usage. Also a common practice is to set the femoral component rotation at 3° external rotation to PCA and valgus resection angle at 5°-7° to anatomical axis of femur. For the reason that the anatomy of each knee is different, it may not be justified to practice such a set protocol in all cases. The aim of the study was to compare the anatomical landmarks used to set up the femoral component rotation and to study the variability in the different anatomical relationships relevant to total knee replacement. The study had 52 patients (94 knees) with grade IV osteoarthritis. Full-length lower limb scanogram and 1 mm cross-sectional cuts of distal femur were taken. aTEA, sTEA, PCL, TL, CTA, PCA, TLA and valgus angles were taken for all knees. aTEA is identifiable in all cases but sTEA in only 59 knees (62.77%). Correspondingly, CTA is calculable in all knees and PCA in 62.77% cases. Mean CTA and mean PCA were 5.4° ± 1.88° SD and 0.71° ± 1.95° SD, respectively. Mean angle between aTEA and sTEA was 4.88. TL is a line difficult to draw because of high incidence of anterior osteophytes, making CTA a more reliable parameter than TLA. Mean TLA was 10.31° ± 3.52° SD. Mean valgus resection angle was 4.86° ± 2.53° SD. Gender- or side-based differences in any of these values were not statistically different. Using aTEA or sTEA can make a big difference in femoral component rotation; therefore, whether aTEA or sTEA should be used needs to be further investigated. CTA, PCA and valgus resection angle need to be individually calculated for each knee. Use of TLA is not recommended.
ISOANTIGENS OF THE H-2 AND Tla LOCI OF THE MOUSE
Boyse, Edward A.; Stockert, Elisabeth; Old, Lloyd J.
1968-01-01
H-2 and TL isoantigens of the mouse are specified by the closely linked genetic loci H-2 and Tla. A. study of their representation on thymocytes was performed in order to reveal any interactions between the determinant genes or their products affecting the synthesis or disposition of these components of the thymocyte surface. The method employed was quantitative absorption of cytotoxic antibody by viable thymocytes. The phenotypic expression of TL antigens was found to reduce the demonstrable amount of certain H-2 antigens to as little as 34% of the quantity demonstrable on TL- thymocytes. A reduction was observed in all three H-2 types tested, (H-2b, H-2a, and H-2k). As antigenic modulation (change of TL phenotype from TL+ to TL-, produced by TL antibody) is known to entail a compensatory increase in H-2(D) antigen, it is concluded that the TL phenotype, rather than the Tla genotype, influences the surface representation of H-2 antigens. The two known TL+ phenotypes of thymocytes (TL.2 and TL.1,2,3) depress H-2 equally. The H-2 specificities affected are those determined by the D end of the E-2 locus, which is adjacent to Tla; antigens of the K end, which is distal to Tla, are not depressed. The reduction of demonstrable H-2 antigen on the thymocytes of TL+ x TL- progeny is half that of thymocytes of TL+ x TL+ progeny and the reduction affects equally the products of both H-2 alleles (cis and trans in relation to Tla), indicating that the mechanism of H-2 reduction by TL is extrachromosomal. Whether it involves diminished synthesis of H-2 or steric masking by TL at the cell membrane is unknown, but in either case the reciprocal relation of TL and H-2(D) antigens implies that they probably occupy adjacent positions on thymocytes and that the gene order, H-2(K): H-2(D):Tla is reflected in cell surface structure. Extrachromosomal interaction, apparently involving control of synthesis, occurs also within the TL system of antigens. Thymocytes of TL.2 x TL.1,2,3 progeny express the full homozygous quantity of antigens TL.1 and TL.3 (but not of TL.2), in contrast to the half-quantity present in thymocytes of TL- x TL.1,2,3 progeny. Another example of interaction is implicit in the finding that thymocytes of TL-1,2,3 x TL.1,2,3 progeny have more TL.2 antigen than thymocytes of TL.2 x TL.2 progeny, but in this instance there is nothing to indicate whether the mechanism is chromosomal or extrachromosomal. Thus the quantitative surface representation of at least some H-2 and TL antigens is influenced by the cellular complement of H-2:Tla genes as a whole. Comparison of H-2 heterozygous thymocytes with H-2 homozygous thymocytes in quantitative absorption tests shows (a) more than the expected 50% of each parental-type H-2 antigen on heterozygous cells, and (b) a greater suppression of H-2 by TL in H-2 heterozygotes in comparison with H-2 homozygotes. Both results may be explained on the basis of differences in the density of H-2 antigenic sites and consequent differences in the efficiency of absorption of H-2 antibody. These considerations may be useful in other contexts, e.g. in estimating the representation of Rh antigens on the red cells of human subjects homozygous and heterozygous for Rh components. PMID:5662018
Spilak, Michal P.; Sigsgaard, Torben; Takai, Hisamitsu; Zhang, Guoqiang
2016-01-01
People spend approximately one third of their life sleeping. Exposure to pollutants in the sleep environment often leads to a variety of adverse health effects, such as development and exacerbation of asthma. Avoiding exposure to these pollutants by providing a sufficient air quality in the sleep environment might be a feasible method to alleviate these health symptoms. We performed full-scale laboratory measurements using a thermal manikin positioned on an experimental bed. Three ventilation settings were tested: with no filtration system operated, use of portable air cleaner and use of a temperature-controlled laminar airflow (TLA) device. The first part of the experiment investigated the air-flow characteristics in the breathing zone. In the second part, particle removal efficiency was estimated. Measured in the breathing zone, the room air cleaner demonstrated high turbulence intensity, high velocity and turbulence diffusivity level, with a particle reduction rate of 52% compared to baseline after 30 minutes. The TLA device delivered a laminar airflow to the breathing zone with a reduction rate of 99.5%. During a periodical duvet lifting mimicking a subject’s movement in bed, the particle concentration was significantly lower with the TLA device compared to the room air cleaner. The TLA device provided a barrier which significantly reduced the introduction of airborne particles into the breathing zone. Further studies should be conducted for the understanding of the transport of resuspended particles between the duvet and the laying body. PMID:27898693
Spilak, Michal P; Sigsgaard, Torben; Takai, Hisamitsu; Zhang, Guoqiang
2016-01-01
People spend approximately one third of their life sleeping. Exposure to pollutants in the sleep environment often leads to a variety of adverse health effects, such as development and exacerbation of asthma. Avoiding exposure to these pollutants by providing a sufficient air quality in the sleep environment might be a feasible method to alleviate these health symptoms. We performed full-scale laboratory measurements using a thermal manikin positioned on an experimental bed. Three ventilation settings were tested: with no filtration system operated, use of portable air cleaner and use of a temperature-controlled laminar airflow (TLA) device. The first part of the experiment investigated the air-flow characteristics in the breathing zone. In the second part, particle removal efficiency was estimated. Measured in the breathing zone, the room air cleaner demonstrated high turbulence intensity, high velocity and turbulence diffusivity level, with a particle reduction rate of 52% compared to baseline after 30 minutes. The TLA device delivered a laminar airflow to the breathing zone with a reduction rate of 99.5%. During a periodical duvet lifting mimicking a subject's movement in bed, the particle concentration was significantly lower with the TLA device compared to the room air cleaner. The TLA device provided a barrier which significantly reduced the introduction of airborne particles into the breathing zone. Further studies should be conducted for the understanding of the transport of resuspended particles between the duvet and the laying body.
Can the Risks of Cerebrospinal Fluid Leak After Vestibular Schwannoma Surgery Be Predicted?
Russel, Adrien; Hoffmann, Charles P; Nguyen, Duc T; Beurton, Renaud; Parietti-Winkler, Cécile
2017-02-01
Identifying predictive factors of cerebrospinal fluid (CSF) leak after translabyrinthine approach (TLA) for vestibular schwannoma. Retrospective study. Tertiary care center. All patients (n = 275) operated for a vestibular schwannoma by TLA between 2004 and 2013 were included. Vestibular schwannoma surgery by TLA. The rate of postoperative CSF leak considering the age, sex, body mass index (BMI), tumor staging, and duration of surgical procedure. A logistic regression model was used to identify the predictors and compute a biometric predictive model of CSF leak. Thirty-three patients (12.0%) developed a CSF leak after surgery. In a multivariable model, an increased risk of CSF leak was found for younger patients (OR 0.95, 95% CI 0.92-0.98), longer duration of surgery (OR 1.85, 95% CI 1.12-3.05), and the male sex (0 = male; 1 = female; OR 0.22, 95% CI 0.09-0.54), while also adjusting for BMI. The probability of developing a CSF leak after vestibular schwannoma surgery was calculated using a statistical prediction model, with a percentage of false negative of 7.0% and an overall correct prediction of 88.4%. The predictors of CSF leak after TLA for vestibular schwannoma are young age, male sex, longer duration of surgery, which adjusting for BMI. In this regard, the surgical team should adapt its management during pre- and postoperative period to decrease the likelihood of a leak.
Long-Term Clinical Outcome After Titanium Lunate Arthroplasty for Kienböck Disease.
Viljakka, Timo; Tallroth, Kaj; Vastamäki, Martti
2018-04-09
Titanium lunate arthroplasty (TLA) for Kienböck disease was introduced in 1984 to address the silicone-wear particle problem common to silicone lunate implants. We sought to study the outcome of TLA. We identified 11 patients from our hospital database who had undergone TLA between 2001 and 2010. We evaluated pain, range of motion (ROM), function, and radiological outcome at a mean 11 years after surgery. We compared preoperative ROM and radiological findings with final follow-up in the ipsilateral wrist and also made comparisons with the contralateral wrists. No implants were removed, and no wrist joints were fused. Pain on the visual analog scale averaged 0.5 at rest, 0.3 at night, and 2.7 during heavy exertion. Seven patients had no pain at rest and 9 had no pain at night. Range of motion reached 70% of that of the contralateral wrist, and strength reached 81%. The Disabilities of the Arm, Shoulder, and Hand (DASH) score averaged 9.6, optional DASH 9.7, and Mayo wrist score 67.7. Radiologically, only Ståhl and arthrosis indexes differed significantly between affected and unaffected wrists. Two patients had a dorsally dislocated implant, meaning that around 20% of our cases probably meet the criteria for failure. The longer-term results of TLA for stage III Kienböck disease are promising. Therapeutic IV. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.
Development of a Methodology for Assessing Aircrew Workloads.
1981-11-01
Workload Feasibility Study. .. ...... 52 Subjects. .. .............. ........ 53 Equipment .. ............... ....... 53 Date Analysis ... analysis ; simulation; standard time systems; switching synthetic time systems; task activities; task interference; time study; tracking; workload; work sampl...standard data systems, information content analysis , work sampling and job evaluation. Con- ventional methods were found to be deficient in accounting
Characterization of a new chimeric marker vaccine candidate with a mutated antigenic E2-epitope.
Reimann, Ilona; Depner, Klaus; Utke, Katrin; Leifer, Immanuel; Lange, Elke; Beer, Martin
2010-04-21
A new chimeric pestivirus "CP7_E1E2alf_TLA", based on the infectious cDNA of bovine viral diarrhea virus (BVDV) strain CP7, was constructed. The substitution of BVDV E1 and E2 with the respective proteins of classical swine fever (CSF) strain Alfort 187 allows an optimal heterodimerization of E1 and E2 in the chimeric virus, which is beneficial for efficient and authentic virus assembly and growth. In addition, for implementation of E2-based marker diagnostics, the previously described antigenic CSFV-specific TAVSPTTLR epitope was exchanged with the corresponding E2-epitope of BVDV strain CP7. Recombinant virus CP7_E1E2alf_TLA displayed a growth defect, and was not reacting with monoclonal antibodies used in commercial E2 antibody blocking ELISAs. Therefore, efficacy as well as marker properties of CP7_E1E2alf_TLA were investigated in an animal experiment with both a high dose and a low dose vaccine preparation. All CP7_E1E2alf_TLA-vaccinated animals seroconverted until day 28 post-vaccination with neutralizing antibodies. Furthermore, at the day of challenge infection CP7_E1E2alf_TLA-immunized animals showed distinct lower ELISA values in a commercial CSFV E2 antibody test in comparison to the C-strain vaccinated controls. However, E2-ELISA reactivity as well as neutralizing titers were directly connected to the dosage used for vaccination, and only the low dose group had E2-ELISA values below threshold until challenge infection. Following challenge infection with highly virulent CSFV strain Koslov, all vaccinees were protected, however, short-term fever episodes and very limited CSFV genome detection with very low copy numbers could be observed. In conclusion, manipulation of the TAVSPTTLR-epitope within the tested chimeric virus resulted in an slightly reduced efficacy, but the E2 marker properties unexpectedly did not allow a clear differentiation of infected from vaccinated animals in some cases. Copyright 2009 Elsevier B.V. All rights reserved.
Armbruster, David A; Overcash, David R; Reyes, Jaime
2014-01-01
The era of automation arrived with the introduction of the AutoAnalyzer using continuous flow analysis and the Robot Chemist that automated the traditional manual analytical steps. Successive generations of stand-alone analysers increased analytical speed, offered the ability to test high volumes of patient specimens, and provided large assay menus. A dichotomy developed, with a group of analysers devoted to performing routine clinical chemistry tests and another group dedicated to performing immunoassays using a variety of methodologies. Development of integrated systems greatly improved the analytical phase of clinical laboratory testing and further automation was developed for pre-analytical procedures, such as sample identification, sorting, and centrifugation, and post-analytical procedures, such as specimen storage and archiving. All phases of testing were ultimately combined in total laboratory automation (TLA) through which all modules involved are physically linked by some kind of track system, moving samples through the process from beginning-to-end. A newer and very powerful, analytical methodology is liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). LC-MS/MS has been automated but a future automation challenge will be to incorporate LC-MS/MS into TLA configurations. Another important facet of automation is informatics, including middleware, which interfaces the analyser software to a laboratory information systems (LIS) and/or hospital information systems (HIS). This software includes control of the overall operation of a TLA configuration and combines analytical results with patient demographic information to provide additional clinically useful information. This review describes automation relevant to clinical chemistry, but it must be recognised that automation applies to other specialties in the laboratory, e.g. haematology, urinalysis, microbiology. It is a given that automation will continue to evolve in the clinical laboratory, limited only by the imagination and ingenuity of laboratory scientists. PMID:25336760
Armbruster, David A; Overcash, David R; Reyes, Jaime
2014-08-01
The era of automation arrived with the introduction of the AutoAnalyzer using continuous flow analysis and the Robot Chemist that automated the traditional manual analytical steps. Successive generations of stand-alone analysers increased analytical speed, offered the ability to test high volumes of patient specimens, and provided large assay menus. A dichotomy developed, with a group of analysers devoted to performing routine clinical chemistry tests and another group dedicated to performing immunoassays using a variety of methodologies. Development of integrated systems greatly improved the analytical phase of clinical laboratory testing and further automation was developed for pre-analytical procedures, such as sample identification, sorting, and centrifugation, and post-analytical procedures, such as specimen storage and archiving. All phases of testing were ultimately combined in total laboratory automation (TLA) through which all modules involved are physically linked by some kind of track system, moving samples through the process from beginning-to-end. A newer and very powerful, analytical methodology is liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). LC-MS/MS has been automated but a future automation challenge will be to incorporate LC-MS/MS into TLA configurations. Another important facet of automation is informatics, including middleware, which interfaces the analyser software to a laboratory information systems (LIS) and/or hospital information systems (HIS). This software includes control of the overall operation of a TLA configuration and combines analytical results with patient demographic information to provide additional clinically useful information. This review describes automation relevant to clinical chemistry, but it must be recognised that automation applies to other specialties in the laboratory, e.g. haematology, urinalysis, microbiology. It is a given that automation will continue to evolve in the clinical laboratory, limited only by the imagination and ingenuity of laboratory scientists.
Viezel-Mathieu, Alex; Safran, Tyler; Gilardino, Mirko S
2016-09-01
Tongue-lip adhesion (TLA) involves surgically tethering the tongue forward to the lower lip and is a technique to relieve airway obstruction caused by glossoptosis and retrognathia. The purpose of the present study was to evaluate the effectiveness of TLA for the treatment of airway compromise in patients with Pierre Robin sequence (PRS). A comprehensive literature review was performed. Inclusion criteria consisted of patients having undergone isolated tongue lip adhesion and results that included airway outcome. Selected manuscripts were analyzed with regards to patient demographics, principle diagnosis, pre and postintervention airway status, and complications. Thirteen manuscripts met inclusion criteria, yielding 268 patients with PRS who underwent TLA. The mean age at the time of procedure was 30.5 days. Tongue lip adhesion proved to be successful in relieving airway obstruction caused by PRS in 81.3% (n = 218) of patients. Nonsyndromic patients benefited from a higher success rate as compared with the syndromic cohort (91.5% and 79.8% respectively, P = 0.0361). Eight patients who were initially successfully managed with TLA required a repeat procedure due to dehiscence. Tongue-lip adhesion is a safe and effective technique and is associated with lower morbidity and mortality as compared with mandibular distraction osteogenesis and tracheostomy and should be considered in patients with PRS who fail conservative management. The greater success and lower complication rates in nonsyndromic patients reinforce the importance of proper patient selection and consideration of other techniques such as mandibular distraction osteogenesis should be given in patients with associated syndromic diagnoses.
Genomic constitution of an H-2:Tla variant leukemia.
Shen, F W; Chaganti, R S; Doucette, L A; Litman, G W; Steinmetz, M; Hood, L; Boyse, E A
1984-10-01
A TL+ leukemia of a (B6 X A)F1 hybrid mouse (H-2b/H-2a) was previously subjected to immunoselection against H-2a by passage in (B6 X A.SW)F1 mice (H-2b/H-2s). A variant leukemia line was obtained that serologically lacked not only the H-2a phenotype but also the TL phenotype determined by the linked cis Tlaa allele of strain A. The H-2b phenotype and the TL phenotype of the Tlab allele of the B6 strain, which is expressed only by leukemia cells, were retained by the variant. Southern blotting with an H-2 cDNA probe that identifies restriction fragment polymorphisms distinguishing alleles of the H-2 and Tla regions of the B6 and A strains indicates that both the H-2a and Tlaa alleles are missing from the genome of this H-2a:Tlaa negative variant. Since the variant has two apparently unaltered chromosomes 17, where the H-2:Tla complex is situated, and since the intensity of bands in Southern blotting is suggestive of H-2b homozygosity, it is considered that loss of the H-2a:Tlaa haplotype by the variant was accompanied by duplication of the H-2b:Tlab haplotype. The implied change from heterozygosity to homozygosity that the variant has undergone with respect to H-2:Tla was not paralleled by a similar change at the three other loci tested, since the variant retained heterozygosity for Pep-3 (chromosome 1), Gpi-1 (chromosome 7), and Es-1 (chromosome 8).
Hodiamont, Caspar J.; de Jong, Menno D.; Overmeijer, Hendri P. J.; van den Boogaard, Mandy; Visser, Caroline E.
2014-01-01
Background Microbiological laboratories seek technologically innovative solutions to cope with large numbers of samples and limited personnel and financial resources. One platform that has recently become available is the Kiestra Total Laboratory Automation (TLA) system (BD Kiestra B.V., the Netherlands). This fully automated sample processing system, equipped with digital imaging technology, allows superior detection of microbial growth. Combining this approach with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MS) (Bruker Daltonik, Germany) is expected to enable more rapid identification of pathogens. Methods Early growth detection by digital imaging using Kiestra TLA combined with MS was compared to conventional methods (CM) of detection. Accuracy and time taken for microbial identification were evaluated for the two methods in 219 clinical blood culture isolates. The possible clinical impact of earlier microbial identification was assessed according to antibiotic treatment prescription. Results Pathogen identification using Kiestra TLA combined with MS resulted in a 30.6 hr time gain per isolate compared to CM. Pathogens were successfully identified in 98.4% (249/253) of all tested isolates. Early microbial identification without susceptibility testing led to an adjustment of antibiotic regimen in 12% (24/200) of patients. Conclusions The requisite 24 hr incubation time for microbial pathogens to reach sufficient growth for susceptibility testing and identification would be shortened by the implementation of Kiestra TLA in combination with MS, compared to the use of CM. Not only can this method optimize workflow and reduce costs, but it can allow potentially life-saving switches in antibiotic regimen to be initiated sooner. PMID:24624346
Patient Safety Incidents and Nursing Workload 1
Carlesi, Katya Cuadros; Padilha, Kátia Grillo; Toffoletto, Maria Cecília; Henriquez-Roldán, Carlos; Juan, Monica Andrea Canales
2017-01-01
ABSTRACT Objective: to identify the relationship between the workload of the nursing team and the occurrence of patient safety incidents linked to nursing care in a public hospital in Chile. Method: quantitative, analytical, cross-sectional research through review of medical records. The estimation of workload in Intensive Care Units (ICUs) was performed using the Therapeutic Interventions Scoring System (TISS-28) and for the other services, we used the nurse/patient and nursing assistant/patient ratios. Descriptive univariate and multivariate analysis were performed. For the multivariate analysis we used principal component analysis and Pearson correlation. Results: 879 post-discharge clinical records and the workload of 85 nurses and 157 nursing assistants were analyzed. The overall incident rate was 71.1%. It was found a high positive correlation between variables workload (r = 0.9611 to r = 0.9919) and rate of falls (r = 0.8770). The medication error rates, mechanical containment incidents and self-removal of invasive devices were not correlated with the workload. Conclusions: the workload was high in all units except the intermediate care unit. Only the rate of falls was associated with the workload. PMID:28403334
Spears, Bryan M; Lürling, Miquel; Yasseri, Said; Castro-Castellon, Ana T; Gibbs, Max; Meis, Sebastian; McDonald, Claire; McIntosh, John; Sleep, Darren; Van Oosterhout, Frank
2013-10-01
Phoslock(®) is a lanthanum (La) modified bentonite clay that is being increasingly used as a geo-engineering tool for the control of legacy phosphorus (P) release from lake bed sediments to overlying waters. This study investigates the potential for negative ecological impacts from elevated La concentrations associated with the use of Phoslock(®) across 16 case study lakes. Impact-recovery trajectories associated with total lanthanum (TLa) and filterable La (FLa) concentrations in surface and bottom waters were quantified over a period of up to 60 months following Phoslock(®) application. Both surface and bottom water TLa and FLa concentrations were <0.001 mg L(-1) in all lakes prior to the application of Phoslock(®). The effects of Phoslock(®) application were evident in the post-application maximum TLa and FLa concentrations reported for surface waters between 0.026 mg L(-1)-2.30 mg L(-1) and 0.002 mg L(-1) to 0.14 mg L(-1), respectively. Results of generalised additive modelling indicated that recovery trajectories for TLa and FLa in surface and bottom waters in lakes were represented by 2nd order decay relationships, with time, and that recovery reached an end-point between 3 and 12 months post-application. Recovery in bottom water was slower (11-12 months) than surface waters (3-8 months), most probably as a result of variation in physicochemical conditions of the receiving waters and associated effects on product settling rates and processes relating to the disturbance of bed sediments. CHEAQS PRO modelling was also undertaken on 11 of the treated lakes in order to predict concentrations of La(3+) ions and the potential for negative ecological impacts. This modelling indicated that the concentrations of La(3+) ions will be very low (<0.0004 mg L(-1)) in lakes of moderately low to high alkalinity (>0.8 mEq L(-1)), but higher (up to 0.12 mg L(-1)) in lakes characterised by very low alkalinity. The effects of elevated La(3+) concentrations following Phoslock(®) applications in lakes of very low alkalinity requires further evaluation. The implications for the use of Phoslock(®) in eutrophication management are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.
Aduse-Opoku, J; Slaney, J M; Rangarajan, M; Muir, J; Young, K A; Curtis, M A
1997-08-01
The prpR1 gene of Porphyromonas gingivalis W50 encodes the polyprotein precursor (PrpRI) of an extracellular arginine-specific protease. PrpRI is organized into four distinct domains (pro, alpha, beta, and gamma) and is processed to a heterodimeric protease (RI) which comprises the alpha and beta components in a noncovalent association. The alpha component contains the protease active site, whereas the beta component appears to have a role in adherence and hemagglutination processes. DNA sequences homologous to the coding region for the RI beta component are present at multiple loci on the P. gingivalis chromosome and may represent a family of related genes. In this report, we describe the cloning, sequence analysis, and characterization of one of these homologous loci isolated in plasmid pJM7. The 6,041-bp P. gingivalis DNA fragment in pJM7 contains a major open reading frame of 3,291 bp with coding potential for a protein with an Mr 118,700. An internal region of the deduced sequence (V304 to N768) shows 98% identity to the beta domain of PrpRI, and the recombinant product of pJM7 is immunoreactive with an antibody specific to the RI beta component. The N terminus of the deduced sequence has regional similarity to TonB-linked receptors which are frequently involved in periplasmic translocation of hemin, iron, colicins, or vitamin B12 in other bacteria. We have therefore designated this gene tla (TonB-linked adhesin). In contrast to the parent strain, an isogenic mutant of P. gingivalis W50 in which the tla was insertionally inactivated was unable to grow in medium containing low concentrations of hemin (<2.5 mg liter(-1)), and hemin-depleted cells of this mutant failed to respond to hemin in an agar diffusion plate assay. These data suggest a role for this gene product in hemin acquisition and utilization. Furthermore, the mutant produced significantly less arginine- and lysine-specific protease activities than the parent strain, indicating that there may be a regulatory relationship between tla and other members of this gene family.
Aduse-Opoku, J; Slaney, J M; Rangarajan, M; Muir, J; Young, K A; Curtis, M A
1997-01-01
The prpR1 gene of Porphyromonas gingivalis W50 encodes the polyprotein precursor (PrpRI) of an extracellular arginine-specific protease. PrpRI is organized into four distinct domains (pro, alpha, beta, and gamma) and is processed to a heterodimeric protease (RI) which comprises the alpha and beta components in a noncovalent association. The alpha component contains the protease active site, whereas the beta component appears to have a role in adherence and hemagglutination processes. DNA sequences homologous to the coding region for the RI beta component are present at multiple loci on the P. gingivalis chromosome and may represent a family of related genes. In this report, we describe the cloning, sequence analysis, and characterization of one of these homologous loci isolated in plasmid pJM7. The 6,041-bp P. gingivalis DNA fragment in pJM7 contains a major open reading frame of 3,291 bp with coding potential for a protein with an Mr 118,700. An internal region of the deduced sequence (V304 to N768) shows 98% identity to the beta domain of PrpRI, and the recombinant product of pJM7 is immunoreactive with an antibody specific to the RI beta component. The N terminus of the deduced sequence has regional similarity to TonB-linked receptors which are frequently involved in periplasmic translocation of hemin, iron, colicins, or vitamin B12 in other bacteria. We have therefore designated this gene tla (TonB-linked adhesin). In contrast to the parent strain, an isogenic mutant of P. gingivalis W50 in which the tla was insertionally inactivated was unable to grow in medium containing low concentrations of hemin (<2.5 mg liter(-1)), and hemin-depleted cells of this mutant failed to respond to hemin in an agar diffusion plate assay. These data suggest a role for this gene product in hemin acquisition and utilization. Furthermore, the mutant produced significantly less arginine- and lysine-specific protease activities than the parent strain, indicating that there may be a regulatory relationship between tla and other members of this gene family. PMID:9244265
The workload book: Assessment of operator workload to engineering systems
NASA Technical Reports Server (NTRS)
Gopher, D.
1983-01-01
The structure and initial work performed toward the creation of a handbook for workload analysis directed at the operational community of engineers and human factors psychologists are described. The goal, when complete, will be to make accessible to such individuals the results of theoretically-based research that are of practical interest and utility in the analysis and prediction of operator workload in advanced and existing systems. In addition, the results of laboratory study focused on the development of a subjective rating technique for workload that is based on psychophysical scaling techniques are described.
NASA Astrophysics Data System (ADS)
Hu, Qingmei; Zou, Bingsuo; Zhang, Yongyou
2018-03-01
Transmission and correlation properties of a two-photon pulse are studied in a one-dimensional waveguide (1DW) in the presence of three types of quantum emitters: two-level atom (TLA), side optical cavity (SOC), and Jaynes-Cummings model (JCM). Since there are many plane-wave components for a two-photon pulse, a nonlinear waveguide dispersion is used instead of the linearized one. The two-photon transmission spectra become flatter with decreasing the pulse width. With respect to the δ coupling between the 1DW and quantum emitter the transmission dips show a blueshift for the non-δ one and the blueshift first increases and then decreases with increasing the width of the coupling. The TLA and JCM can induce an effective photon-photon interaction that depends on the distance between the two photons, while the SOC cannot. We show that the 1DW coupled with the TLA or JCM is able to evaluate the overlap of the two photons and that the non-δ coupling has potential for controlling the two-photon correlation.
Effect of heating rate on kinetic parameters of β-irradiated Li2B4O7:Cu,Ag,P in TSL measurements
NASA Astrophysics Data System (ADS)
Türkler Ege, A.; Ekdal, E.; Karali, T.; Can, N.; Prokic, M.
2007-03-01
The effect of heating rate on the thermally stimulated luminescence (TSL) emission due to the temperature lag (TLA) between the TSL material and the heating element has been investigated using Li2B4O7:Cu,Ag,P dosimetric materials. The TLA becomes significant when the material is heated at high heating rates. TSL glow curves of Li2B4O7:Cu,Ag,P material showed two main peaks after β-irradiation. The kinetic parameters, namely activation energy (E) and frequency factor (s) associated with the high temperature main peak of Li2B4O7:Cu,Ag,P were determined using the method of various heating rates (VHR), in which heating rates from 1 to 40 K s-1 were used. It is assumed that non-ideal heat transfer between the heater and the material may cause significant inconsistency of kinetic parameter values obtained with different methods. The effect of TLA on kinetic parameters of the dosimeter was examined.
Qin, D L; Jin, X N; Wang, S J; Wang, J J; Mamat, N; Wang, F J; Wang, Y; Shen, Z A; Sheng, L G; Forsman, M; Yang, L Y; Wang, S; Zhang, Z B; He, L H
2018-06-18
To form a new assessment method to evaluate postural workload comprehensively analyzing the dynamic and static postural workload for workers during their work process to analyze the reliability and validity, and to study the relation between workers' postural workload and work-related musculoskeletal disorders (WMSDs). In the study, 844 workers from electronic and railway vehicle manufacturing factories were selected as subjects investigated by using the China Musculoskeletal Questionnaire (CMQ) to form the postural workload comprehensive assessment method. The Cronbach's α, cluster analysis and factor analysis were used to assess the reliability and validity of the new assessment method. Non-conditional Logistic regression was used to analyze the relation between workers' postural workload and WMSDs. Reliability of the assessment method for postural workload: internal consistency analysis results showed that Cronbach's α was 0.934 and the results of split-half reliability indicated that Spearman-Brown coefficient was 0.881 and the correlation coefficient between the first part and the second was 0.787. Validity of the assessment method for postural workload: the results of cluster analysis indicated that square Euclidean distance between dynamic and static postural workload assessment in the same part or work posture was the shortest. The results of factor analysis showed that 2 components were extracted and the cumulative percentage of variance achieved 65.604%. The postural workload score of the different occupational workers showed significant difference (P<0.05) by covariance analysis. The results of nonconditional Logistic regression indicated that alcohol intake (OR=2.141, 95%CI 1.337-3.428) and obesity (OR=3.408, 95%CI 1.629-7.130) were risk factors for WMSDs. The risk for WMSDs would rise as workers' postural workload rose (OR=1.035, 95%CI 1.022-1.048). There was significant different risk for WMSDs in the different groups of workers distinguished by work type, gender and age. Female workers exhibited a higher prevalence for WMSDs (OR=2.626, 95%CI 1.414-4.879) and workers between 30-40 years of age (OR=1.909, 95%CI 1.237-2.946) as compared with those under 30. This method for comprehensively assessing postural workload is reliable and effective when used in assembling workers, and there is certain relation between the postural workload and WMSDs.
Boyse, E A; Stockert, E; Old, L J
1968-07-01
H-2 and TL isoantigens of the mouse are specified by the closely linked genetic loci H-2 and Tla. A. study of their representation on thymocytes was performed in order to reveal any interactions between the determinant genes or their products affecting the synthesis or disposition of these components of the thymocyte surface. The method employed was quantitative absorption of cytotoxic antibody by viable thymocytes. The phenotypic expression of TL antigens was found to reduce the demonstrable amount of certain H-2 antigens to as little as 34% of the quantity demonstrable on TL- thymocytes. A reduction was observed in all three H-2 types tested, (H-2(b), H-2(a), and H-2(k)). As antigenic modulation (change of TL phenotype from TL+ to TL-, produced by TL antibody) is known to entail a compensatory increase in H-2(D) antigen, it is concluded that the TL phenotype, rather than the Tla genotype, influences the surface representation of H-2 antigens. The two known TL+ phenotypes of thymocytes (TL.2 and TL.1,2,3) depress H-2 equally. The H-2 specificities affected are those determined by the D end of the E-2 locus, which is adjacent to Tla; antigens of the K end, which is distal to Tla, are not depressed. The reduction of demonstrable H-2 antigen on the thymocytes of TL+ x TL- progeny is half that of thymocytes of TL+ x TL+ progeny and the reduction affects equally the products of both H-2 alleles (cis and trans in relation to Tla), indicating that the mechanism of H-2 reduction by TL is extrachromosomal. Whether it involves diminished synthesis of H-2 or steric masking by TL at the cell membrane is unknown, but in either case the reciprocal relation of TL and H-2(D) antigens implies that they probably occupy adjacent positions on thymocytes and that the gene order, H-2(K): H-2(D):Tla is reflected in cell surface structure. Extrachromosomal interaction, apparently involving control of synthesis, occurs also within the TL system of antigens. Thymocytes of TL.2 x TL.1,2,3 progeny express the full homozygous quantity of antigens TL.1 and TL.3 (but not of TL.2), in contrast to the half-quantity present in thymocytes of TL- x TL.1,2,3 progeny. Another example of interaction is implicit in the finding that thymocytes of TL-1,2,3 x TL.1,2,3 progeny have more TL.2 antigen than thymocytes of TL.2 x TL.2 progeny, but in this instance there is nothing to indicate whether the mechanism is chromosomal or extrachromosomal. Thus the quantitative surface representation of at least some H-2 and TL antigens is influenced by the cellular complement of H-2:Tla genes as a whole. Comparison of H-2 heterozygous thymocytes with H-2 homozygous thymocytes in quantitative absorption tests shows (a) more than the expected 50% of each parental-type H-2 antigen on heterozygous cells, and (b) a greater suppression of H-2 by TL in H-2 heterozygotes in comparison with H-2 homozygotes. Both results may be explained on the basis of differences in the density of H-2 antigenic sites and consequent differences in the efficiency of absorption of H-2 antibody. These considerations may be useful in other contexts, e.g. in estimating the representation of Rh antigens on the red cells of human subjects homozygous and heterozygous for Rh components.
Erosion measurement techniques for plasma-driven railgun barrels
NASA Astrophysics Data System (ADS)
Jamison, K. A.; Niiler, Andrus
1987-04-01
Plasma-driven railguns are now in operation at several locations throughout the world. All share common problems in barrel erosion arising from the fact that the bore surface must contain a high temperature plasma armature which transmits the acceleration force to a projectile. The plasma temperature at the core of the armature is estimated to be 30 000 K or higher. Such conditions are erosive to most materials even when the exposure time is 100 μs or less. We have adapted two accelerator based techniques to aid in the study of this erosion. The first technique involves the collection and analysis of material ablated and left behind by the plasma. This analysis is based on the unfolding of the Rutherford backscattered (RBS) spectra of 1 MeV deuterons incident on residue collected from a railgun bore. The second technique is an erosion measurement involving thin layer activation (TLA) of surfaces. In this process, the copper rail surface is activated by 2.4 MeV protons creating a relatively thin (3 m) layer sparsely seeded with a long lived zinc isotope. Monitoring the decay of the activated sample before and after a firing can detect surface wear of about 0. 1 m. Results from the RBS and TLA experiments on the BRL plasma driven railgun are described.
Predicting operator workload during system design
NASA Technical Reports Server (NTRS)
Aldrich, Theodore B.; Szabo, Sandra M.
1988-01-01
A workload prediction methodology was developed in response to the need to measure workloads associated with operation of advanced aircraft. The application of the methodology will involve: (1) conducting mission/task analyses of critical mission segments and assigning estimates of workload for the sensory, cognitive, and psychomotor workload components of each task identified; (2) developing computer-based workload prediction models using the task analysis data; and (3) exercising the computer models to produce predictions of crew workload under varying automation and/or crew configurations. Critical issues include reliability and validity of workload predictors and selection of appropriate criterion measures.
NASA Technical Reports Server (NTRS)
Horst, Richard L.; Mahaffey, David L.; Munson, Robert C.
1989-01-01
The present Phase 2 small business innovation research study was designed to address issues related to scalp-recorded event-related potential (ERP) indices of mental workload and to transition this technology from the laboratory to cockpit simulator environments for use as a systems engineering tool. The project involved five main tasks: (1) Two laboratory studies confirmed the generality of the ERP indices of workload obtained in the Phase 1 study and revealed two additional ERP components related to workload. (2) A task analysis' of flight scenarios and pilot tasks in the Advanced Concepts Flight Simulator (ACFS) defined cockpit events (i.e., displays, messages, alarms) that would be expected to elicit ERPs related to workload. (3) Software was developed to support ERP data analysis. An existing ARD-proprietary package of ERP data analysis routines was upgraded, new graphics routines were developed to enhance interactive data analysis, and routines were developed to compare alternative single-trial analysis techniques using simulated ERP data. (4) Working in conjunction with NASA Langley research scientists and simulator engineers, preparations were made for an ACFS validation study of ERP measures of workload. (5) A design specification was developed for a general purpose, computerized, workload assessment system that can function in simulators such as the ACFS.
Sabapathy, Kalpana; Mubekapi-Musadaidzwa, Constance; Mulubwa, Chama; Schaap, Ab; Hoddinott, Graeme; Stangl, Anne; Floyd, Sian; Ayles, Helen; Fidler, Sarah; Hayes, Richard
2017-12-01
HPTN 071 (PopART) is a three-arm community randomized trial in Zambia and South Africa evaluating the impact of a combination HIV prevention package, including universal test and treat (UTT), on HIV incidence. This nested study examined factors associated with timely linkage-to-care and ART initiation (TLA) (i.e. within six-months of referral) in the context of UTT within the intervention communities of the HPTN 071 (PopART) trial. Of the 7572 individuals identified as persons living with HIV (PLWH) (and not on antiretroviral treatment (ART)) during the first year of the PopART intervention provided by Community HIV-care Providers (CHiPs) through door-to-door household visits, individuals who achieved TLA (controls) and those who did not (cases), stratified by gender and community, were randomly selected to be re-contacted for interview. Standardized questionnaires were administered to explore factors potentially associated with TLA, including demographic and behavioural characteristics, and participants' opinions on HIV and related services. Odds ratios comparing cases and controls were estimated using a multi-variable logistic regression. Data from 705 participants (333 cases/372 controls) were analysed. There were negligible differences between cases and controls by demographic characteristics including age, marital or socio-economic position. Prior familiarity with the CHiPs encouraged TLA (aOR of being a case: 0.58, 95% CI: 0.39 to 0.86, p = 0.006). Participants who found clinics overcrowded (aOR: 1.51, 95% CI: 1.08 to 2.12, p = 0.006) or opening hours inconvenient (aOR: 1.63, 95% CI: 1.06 to 2.51, p = 0.02) were less likely to achieve TLA, as were those expressing stronger feelings of shame about having HIV (p trend = 0.007). Expressing "not feeling ready" (aOR: 2.75, 95% CI: 1.89 to 4.01, p < 0.001) and preferring to wait until they felt sick (aOR: 2.00, 95% CI: 1.27 to 3.14, p = 0.02) were similarly indicative of being a case. Worrying about being seen in the clinic or about how staff treated patients was not associated with TLA. While the association was not strong, we found that the greater the number of self-reported lifetime sexual partners the more likely participants were to achieve TLA (p trend = 0.06). There was some evidence that participants with HIV-positive partners on ART were less likely to be cases (aOR: 0.75, 95% CI: 0.53 to 1.06, p = 0.07). The lack of socio-demographic differences between cases and controls is encouraging for a "universal" intervention that seeks to ensure high coverage across whole communities. Making clinics more "patient-friendly" could enhance treatment uptake further. The finding that those with higher risk behaviour are more actively engaging with UTT holds promise for treatment-as-prevention. © 2017 The Authors. Journal of the International AIDS Society published by John Wiley & sons Ltd on behalf of the International AIDS Society.
Cargnelutti, Diego Esteban; Salomón, María Cristina; Celedon, Verónica; García Bustos, María Fernanda; Morea, Gastón; Cuello-Carrión, Fernando Darío; Scodeller, Eduardo Alberto
2016-02-01
A proper adjuvant has a relevant role in vaccine formulations to generate an effective immune response. In this study, total Leishmania antigen (TLA) formulated with Montanide ISA 763 or R848 as adjuvants were evaluated as a first generation Leishmania vaccine in a murine model. Immunization protocols were tested in BALB/c mice with a subcutaneous prime/boost regimen with an interval of 3 weeks. Mice immunized with unadjuvanted TLA and phosphate-buffered saline (PBS) served as control groups. On Day 21 and Day 36 of the protocol, we evaluated the humoral immune response induced by each formulation. Fifteen days after the boost, the immunized mice were challenged with 1 × 10(5) promastigotes of Leishmania (Leishmania) amazonensis in the right footpad (RFP). The progress of the infection was followed for 10 weeks; at the end of this period, histopathological studies were performed in the RFP. Vaccines formulated with Montanide ISA 763 generated an increase in the production of immunoglobulin G (IgG; p < 0.05) compared with the control group. There were no statistically significant differences in IgG1 production between the study groups. However, immunization with TLA-Montanide ISA 763 resulted in an increase in IgG2a compared to the unadjuvanted control (p < 0.001). Also noteworthy was the fact that a significant reduction in swelling and histopathological damage of the RFP was recorded with the Montanide ISA 763 formulation. We conclude that the immunization of BALB/c mice with a vaccine formulated with TLA and Montanide ISA 763 generated a protective immune response against L. (L.) amazonensis, characterized by an intense production of IgG2a. Copyright © 2014. Published by Elsevier B.V.
Genomic constitution of an H-2:Tla variant leukemia.
Shen, F W; Chaganti, R S; Doucette, L A; Litman, G W; Steinmetz, M; Hood, L; Boyse, E A
1984-01-01
A TL+ leukemia of a (B6 X A)F1 hybrid mouse (H-2b/H-2a) was previously subjected to immunoselection against H-2a by passage in (B6 X A.SW)F1 mice (H-2b/H-2s). A variant leukemia line was obtained that serologically lacked not only the H-2a phenotype but also the TL phenotype determined by the linked cis Tlaa allele of strain A. The H-2b phenotype and the TL phenotype of the Tlab allele of the B6 strain, which is expressed only by leukemia cells, were retained by the variant. Southern blotting with an H-2 cDNA probe that identifies restriction fragment polymorphisms distinguishing alleles of the H-2 and Tla regions of the B6 and A strains indicates that both the H-2a and Tlaa alleles are missing from the genome of this H-2a:Tlaa negative variant. Since the variant has two apparently unaltered chromosomes 17, where the H-2:Tla complex is situated, and since the intensity of bands in Southern blotting is suggestive of H-2b homozygosity, it is considered that loss of the H-2a:Tlaa haplotype by the variant was accompanied by duplication of the H-2b:Tlab haplotype. The implied change from heterozygosity to homozygosity that the variant has undergone with respect to H-2:Tla was not paralleled by a similar change at the three other loci tested, since the variant retained heterozygosity for Pep-3 (chromosome 1), Gpi-1 (chromosome 7), and Es-1 (chromosome 8). Images PMID:6593710
Proton-induced Nuclear Reactions Using Compact High-Contrast High-Intensity Laser
NASA Astrophysics Data System (ADS)
Ogura, Koichi; Shizuma, Toshiyuki; Hayakawa, Takehito; Yogo, Akifumi; Nishiuchi, Mamiko; Orimo, Satoshi; Sagisaka, Akito; Pirozhkov, Alexander; Mori, Michiaki; Kiriyama, Hiromitsu; Kanazawa, Shuhei; Kondo, Shunji; Nakai, Yoshiki; Shimoura, Takuya; Tanoue, Manabu; Akutsu, Atsushi; Motomura, Tomohiro; Okada, Hajime; Kimura, Toyoaki; Oishi, Yuji; Nayuki, Takuya; Fujii, Takashi; Nemoto, Koshichi; Daido, Hiroyuki
2009-06-01
A multi-MeV proton beam driven by a compact laser with an intensity of ˜1020 W/cm2 is used to induce the nuclear reaction 11B(p,n)11C. The total activity of 11C produced after 60 shots of laser irradiation is found to be 11.1+/-0.4 Bq. The possibility of thin layer activation (TLA) analysis using a high-intensity ultrashort-pulse laser is discussed.
Field analysis & eddy current losses calculation in five-phase tubular actuator
NASA Astrophysics Data System (ADS)
Waindok, Andrzej; Tomczuk, Bronislaw
2017-12-01
Field analysis including eddy currents in the magnetic core of five-phase permanent magnet tubular linear actuator (TLA) has been carried out. The eddy currents induced in the magnetic core cause the losses which have been calculated. The results from 2D finite element (FE) analysis have been compared with those from 3D calculations. The losses in the mover of the five-phase actuator are much lower than the losses in its stator. That is why the former ones can be neglected in the computer aided designing. The calculation results have been verified experimentally
Sanders, Gabriel J; Roll, Brad; Peacock, Corey A; Kollock, Roger O
2018-05-02
Sanders, GJ, Roll, B, Peacock, CA, and Kollock, RO. Maximum movement workloads and high-intensity workload demands by position in NCAA division I collegiate football. J Strength Cond Res XX(X): 000-000, 2018-The purpose of the study was to quantify the average and maximum (i.e., peak) movement workloads, and the percent of those workloads performed at high intensity by NCAA division I football athletes during competitive games. Using global positioning system devices (Catapult Sports), low, moderate, and high and total multidirectional movement workloads were quantified by each position. Strategically achieving maximal workloads may improve both conditioning and rehabilitation protocols for athletes as they prepare for competition or return to play after an injury. A total of 40 football athletes were included in the analysis. For the data to be included, athletes were required to participate in ≥75% of the offensive or defensive snaps for any given game. There was a total of 286 data downloads from 13 different games for 8 different football positions. Data were calculated and compared by offensive and defensive position to establish the mean, SD, and maximum workloads during competitive games. The percent high-intensity workload profile was established to assess the total number and percent of high-intensity movement workloads by position. The profile was calculated by dividing a position's maximal high-intensity movement workload by the total (e.g., sum of maximal low, moderate, and high-intensity movements) movement workload. One-way analysis of variances revealed that there was a main effect of football position for total movement workloads and the percent of workloads performed at high intensities (p ≤ 0.025 for all). Maximal high-intensity workloads were 1.6-4.3 times greater than average high-intensity workloads, and the percent of total workloads performed at high intensities varied greatly by position. Strategically training for and using maximal movement workloads can help ensure that athletes are achieving workloads that are similar to the greatest demands of a competitive game.
Fast-axial turbulent flow CO2 laser output characteristics and scaling parameters
NASA Astrophysics Data System (ADS)
Dembovetsky, V. V.; Zavalova, Valentina Y.; Zavalov, Yuri N.
1996-04-01
The paper presents the experimental results of evaluating the output characteristics of TLA- 600 carbon-dioxide laser with axial turbulent gas flow, as well as the results of numerical modeling. The output characteristic and spatial distribution of laser beam were measured with regard to specific energy input, working mixture pressure, active media length and output mirror reflection. The paper presents the results of experimental and theoretical study and design decisions on a succession of similar type industrial carbon-dioxide lasers with fast-axial gas-flow and dc discharge excitation of active medium developed at NICTL RAN. As an illustration, characteristics of the TLA-600 laser are cited.
Linking Simulation with Formal Verification and Modeling of Wireless Sensor Network in TLA+
NASA Astrophysics Data System (ADS)
Martyna, Jerzy
In this paper, we present the results of the simulation of a wireless sensor network based on the flooding technique and SPIN protocols. The wireless sensor network was specified and verified by means of the TLA+ specification language [1]. For a model of wireless sensor network built this way simulation was carried with the help of specially constructed software tools. The obtained results allow us to predict the behaviour of the wireless sensor network in various topologies and spatial densities. Visualization of the output data enable precise examination of some phenomenas in wireless sensor networks, such as a hidden terminal, etc.
Magnetoelectric control of spin-chiral ferroelectric domains in a triangular lattice antiferromagnet
NASA Astrophysics Data System (ADS)
Kimura, Kenta; Nakamura, Hiroyuki; Ohgushi, Kenya; Kimura, Tsuyoshi
2008-10-01
We have grown single crystals of a triangular lattice antiferromagnet (TLA), CuCrO2 , and investigated the correlation between magnetic and dielectric properties. Two magnetic phase transitions are observed at TN2≈24.2K and TN1≈23.6K . It was found that ferroelectric polarization along the triangular lattice plane develops at TN1 , suggesting that the system undergoes a transition into an out-of-plane 120° spin-chiral phase at TN1 . The TLA provides an opportunity for unique magnetoelectric control of spin-chiral ferroelectric domain structures by means of electric and/or magnetic fields.
NASA Astrophysics Data System (ADS)
Gonzales, Melissa
To evaluate those factors which influence the assignment of ozone ( O3) exposures in an epidemiologic context a field study was conducted in the South Coast Air Basin (SoCAB) during the summer of 19% in which time, location, activity (TLA) information and direct measurements of personal O3 exposure were concurrently collected on a group of college students. Current and past O3 exposures were modeled and evaluated as a function of ambient O 3, activity and mobility patterns, indoor ventilation, and recalled TLA information collected one year later. The effect of these factors on the within- and between-subject exposure variability assigned by ecologic (EC) and microenvironment (MEV) models were examined by two-hour intervals, on weekends and weekdays, and by monitoring week compared to personal exposures measured with a passive sampling device (PSD). The students reported spending 85% of their time inside, 7% outside and 8% in- transit. More time was spent outdoors on weekends than on weekdays. Ambient O3 levels were also higher on weekends. In the study area, where a dense O3 monitoring network and the appropriate topography exist fixed-site O3 accurately assigned ambient O3 levels within a 10 mile radius. The variation in the ecologic exposure assignments was low compared to the estimated variation among PSD-measured and MEV-modeled estimates due to the low spatial variation of ambient O3 levels across the SoCAB areas visited by the students. MEV and PSD exposure estimates better captured the variability of personal exposure in any given ambient spatial regimen compared to ecologic exposure assignments. MEV exposure estimates based on recalled TLA patterns, were similar to the MEV estimates based on diary-recorded TLA patterns. For this study population, PSD-measured O3 exposures were estimated to average 32% lower than ``true'' exposure levels due to indoor/outdoor differences in the PSD collection rate. The level of detail obtained from the TLA diary is not necessary for the assignment of current of past O3 exposures in epidemiologic studies. It may be more adventitious to characterize the locations visited, and indoor and outdoor time with the greatest accuracy possible and to use these data to estimate exposure from nearest-monitor ambient O 3 measurements and sets of indoor/outdoor O3 ratios validated to reflect personal exposure within indoor microenvironments.
Cervellione, F; McGurk, C; Berger Eriksen, T; Van den Broeck, W
2017-11-01
Under normal farming conditions, shrimp can experience starvation periods attributable to disease outbreaks or adverse environmental conditions. Starvation leads to significant morphological changes in the hepatopancreas (HP), being the main organ for absorption and storage of nutrients. In the literature, limited research has described the effect on the HP of periods of starvation followed by refeeding and none in whiteleg shrimp (Penaeus vannamei) using computer-assisted image analysis (CAIA). This study describes the effect of starvation and starvation followed by refeeding on the HP of whiteleg shrimp using CAIA. Visiopharm ® software was used to quantify the following morphological parameters, measured as ratio to the total tissue area (TLA): total lumen area (TLA:TTA), haemocytic infiltration area in the intertubular spaces (HIA:TTA), B-cell vacuole area (VBA:TTA), lipid droplet area within R cells (LDA:TTA) and F-cell area (FCA:TTA). Significant changes were measured for HIA:TTA and LDA:TTA during starvation (increase in HIA:TTA associated with decrease in LDA:TTA) and starvation followed by refeeding (decrease in HIA:TTA associated with increase in LDA:TTA). In the future, HIA:TTA and LDA:TTA have the potential to be used in a pre-emptive manner to monitor the health of the HP, facilitate early diagnosis of diseases and study the pathophysiology of the organ. © 2017 John Wiley & Sons Ltd.
Strayer, David L; Cooper, Joel M; Turrill, Jonna; Coleman, James R; Hopman, Rachel J
2017-06-01
The goal of this research was to examine the impact of voice-based interactions using 3 different intelligent personal assistants (Apple's Siri , Google's Google Now for Android phones, and Microsoft's Cortana ) on the cognitive workload of the driver. In 2 experiments using an instrumented vehicle on suburban roadways, we measured the cognitive workload of drivers when they used the voice-based features of each smartphone to place a call, select music, or send text messages. Cognitive workload was derived from primary task performance through video analysis, secondary-task performance using the Detection Response Task (DRT), and subjective mental workload. We found that workload was significantly higher than that measured in the single-task drive. There were also systematic differences between the smartphones: The Google system placed lower cognitive demands on the driver than the Apple and Microsoft systems, which did not differ. Video analysis revealed that the difference in mental workload between the smartphones was associated with the number of system errors, the time to complete an action, and the complexity and intuitiveness of the devices. Finally, surprisingly high levels of cognitive workload were observed when drivers were interacting with the devices: "on-task" workload measures did not systematically differ from that associated with a mentally demanding Operation Span (OSPAN) task. The analysis also found residual costs associated using each of the smartphones that took a significant time to dissipate. The data suggest that caution is warranted in the use of smartphone voice-based technology in the vehicle because of the high levels of cognitive workload associated with these interactions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
NASA Astrophysics Data System (ADS)
Lourenço, A. V. S.; Kodaira, C. A.; Souza, E. R.; Felinto, M. C. F. C.; Malta, O. L.; Brito, H. F.
2011-08-01
In the present work, the surface of the Eu-BTC = [Eu(EMA)(H 2O) 2], [Eu(TLA)(H 2O) 4] and [Eu(TMA)(H 2O) 6] complexes (EMA = 1,2,3-benzenetricarboxylate, TLA = 1,2,4-benzenetricarboxylate and TMA = 1,3,5-benzenetricarboxylate) was modified using 3-aminopropyltriethoxysilane (APTES) by a new microwave assisted method that proved to be simple and efficient. According to our observations, the most efficient luminescence is the material based on APTES incorporating [Eu(TMA)(H 2O) 6] complexes, denoted as Eu-TMA-Si, shows the highest emission efficiency. Therefore, it is proposed as a promising material for molecular conjugation in clinical diagnosis.
NASA Astrophysics Data System (ADS)
Ditrói, F.; Takács, S.; Tárkányi, F.; Fenyvesi, A.; Bergman, J.; Heselius, S.-J.; Solin, O.
1995-12-01
Boron of natural composition was investigated in the form of NiBSi metallic-glass foil to determine the cross-section functions of the natB(p,x) 7Be and the natB(d,x) 7Be nuclear reactions. These reactions are very important from the point of view of Thin Layer Activation (TLA) technique to monitor the wear of boron-containing superhard materials (e.g. BN), because the 7Be with its half-life of 53 d and gamma-energy of 447 keV is very suitable for wear measurements. The possibility of recoil-implantation of the radioactive nuclei was also studied.
Novel use of residue from direct coal liquefaction process
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jianli Yang; Zhaixia Wang; Zhenyu Liu
2009-09-15
Direct coal liquefaction residue (DCLR) is, commonly, designed to be used as a feed stock for gasification or combustion. Use of DCLR as a value added product is very important for improving overall economy of direct coal liquefaction processes. This study shows that the DCLR may be used as a pavement asphalt modifier. The modification ability is similar to that of Trinidad Lake Asphalt (TLA), a superior commercial modifier. Asphalts modified by two DCLRs meet the specifications of ASTM D5710 and BSI BS-3690 designated for the TLA-modified asphalts. The required addition amount for the DCLRs tested is less than thatmore » for TLA due possibly to the high content of asphaltene in DCLRs. Different compatibility was observed for the asphalts with the same penetration grade but from the different origin. Different components in the DCLR play different roles in the modification. Positive synergetic effects among the fractions were observed, which may due to the formation of the stable colloid structure. Unlike polymer-type modifier, the structure of asphalt-type modifier has a similarity with petroleum asphalts which favors the formation of a stable dispersed polar fluid (DPF) colloid structure and improves the performance of pavement asphalt. 12 refs., 1 fig., 6 tabs.« less
Adachi, Koko; Kameyama, Eri; Yamada, Masahiro; Nakamura, Tadaho; Uchida, Kentaroh; Hayasaka, Tomoko
2011-10-01
This paper discusses the efficacy and difficulty of the management of monitored anesthesia care (MAC) for inguinal hernia repairs using tumescent local anesthesia(TLA). Eighty patients were retrospectively divided into four groups (all n = 20) according to the drugs used; group P (propofol), group PF (propofol and fentanyl), group PFM (propofol, fentanyl and midazolam), group PR (propofol and remifentanyl). The four groups were analyzed in terms of the applied dose, airway use, wake-up test to determine whether hernia was repaired, postoperative pain and nausea. More propofol was administered in group P than in group PFM and PR. Although, airway was used for nine patients, there was no difference between the four groups. Postoperative pain and nausea also do not differ between the groups. One patient in group P showed unsuccessful repair with wake-up test. MAC shows a beneficial effect on inguinal hernia repairs under TLA. The rate of airway use was as high as eleven percent, and maintenance of the patients' airway requires attention. In terms of wake-up test, propofol combined with opioid administration may be more effective than propofol administration alone. There was no significant difference between the groups in pain and nausea, regardless at the use of fentanyl or remifentanil.
Driver distraction : eye glance analysis and conversation workload.
DOT National Transportation Integrated Search
2015-11-01
The objective of this project was to assess the risk of performing a secondary task while driving a commercial : motor vehicle (CMV). The risk of conversation workload while driving a CMV was also assessed. Conversation : workload is a proxy for cogn...
Initial Technology Assessment for the Environmental Sentinel Biomonitor (ESB) System
2006-08-01
McFarlane-Abdulla E, Andersson M, Barile FA, et al. 1996. MEIC evaluation of acute systemic toxicity Part II. In vitro results from 68 toxicity assays used...to test the first 30 reference chemicals and a comparative cytotoxicity analysis. A TLA 24:273-311. Clemedson C, Andersson M, Aoki Y, Barile FA, et al...Clemedson C, McFarlane-Abdulla E, Andersson M, Barile FA, et al. 1996. MEIC evaluation of acute systemic toxicity Part I. Methodology of 68 in vitro
ERIC Educational Resources Information Center
Botha, P. A.; Swanepoel, S.
2015-01-01
This article reports on the results of a statistical analysis of the weekly working hours of academics in a Faculty of Human and Social Sciences at a South African university. The aim was to quantify, analyse and compare the workload of academic staff. Seventy-five academics self-reported on their workload by completing the workload measuring…
Lou, Amy H; Elnenaei, Manal O; Sadek, Irene; Thompson, Shauna; Crocker, Bryan D; Nassar, Bassam A
2017-10-01
Core laboratory (CL), as a new business model, facilitates consolidation and integration of laboratory services to enhance efficiency and reduce costs. This study evaluates the impact of total laboratory automation system (TLA), electric track vehicle (ETV) system and auto-verification (AV) of results on overall turnaround time (TAT) (phlebotomy to reporting TAT: PR-TAT) within a CL setting. Mean, median and percentage of outlier (OP) for PR-TAT were compared for pre- and post-CL eras using five representative tests based on different request priorities. Comparison studies were also carried out on the intra-laboratory TAT (in-lab to reporting TAT: IR-TAT) and the delivery TAT (phlebotomy to in-lab TAT: PI-TAT) to reflect the efficiency of the TLA (both before and after introducing result AV) and ETV systems respectively. Median PR-TATs for the urgent samples were reduced on average by 16% across all representative analytes. Median PR-TATs for the routine samples were curtailed by 51%, 50%, 49%, 34% and 22% for urea, potassium, thyroid stimulating hormone (TSH), complete blood count (CBC) and prothrombin time (PT) respectively. The shorter PR-TAT was attributed to a significant reduction of IR-TAT through the TLA. However, the median PI-TAT was delayed when the ETV was used. Application of various AV rules shortened the median IR-TATs for potassium and urea. However, the OP of PR-TAT for the STAT requests exceeding 60min were all higher than those from the pre-CL era. TLA and auto-verification rules help to efficiently manage substantial volumes of urgent and routine samples. However, the ETV application as it stands shows a negative impact on the PR-TAT. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.
Kirst, Henning; Shen, Yanxin; Vamvaka, Evangelia; Betterle, Nico; Xu, Dongmei; Warek, Ujwala; Strickland, James A; Melis, Anastasios
2018-04-06
Downregulation in the expression of the signal recognition particle 43 (SRP43) gene in tobacco conferred a truncated photosynthetic light-harvesting antenna (TLA property), and resulted in plants with a greater leaf-to-stem ratio, improved photosynthetic productivity and canopy biomass accumulation under high-density cultivation conditions. Evolution of sizable arrays of light-harvesting antennae in all photosynthetic systems confers a survival advantage for the organism in the wild, where sunlight is often the growth-limiting factor. In crop monocultures, however, this property is strongly counterproductive, when growth takes place under direct and excess sunlight. The large arrays of light-harvesting antennae in crop plants cause the surface of the canopies to over-absorb solar irradiance, far in excess of what is needed to saturate photosynthesis and forcing them to engage in wasteful dissipation of the excess energy. Evidence in this work showed that downregulation by RNA-interference approaches of the Nicotiana tabacum signal recognition particle 43 (SRP43), a nuclear gene encoding a chloroplast-localized component of the photosynthetic light-harvesting assembly pathway, caused a decrease in the light-harvesting antenna size of the photosystems, a corresponding increase in the photosynthetic productivity of chlorophyll in the leaves, and improved tobacco plant canopy biomass accumulation under high-density cultivation conditions. Importantly, the resulting TLA transgenic plants had a substantially greater leaf-to-stem biomass ratio, compared to those of the wild type, grown under identical agronomic conditions. The results are discussed in terms of the potential benefit that could accrue to agriculture upon application of the TLA-technology to crop plants, entailing higher density planting with plants having a greater biomass and leaf-to-stem ratio, translating into greater crop yields per plant with canopies in a novel agronomic configuration.
Meng, Fengqun; Zhang, Guangfu; Li, Xincheng; Niklas, Karl J; Sun, Shucun
2015-06-01
During the development of woody twigs, the growth in leaf may or may not be proportional to the growth in stem. The presence or absence of a synchronicity between these two phenologies may reflect differences in life history adaptive strategies concerning carbon gain. We hypothesized that sun-adapted species are more likely to be less synchronous between growths in total leaf area (TLA) and stem length compared with shade-adapted species, with a bias in growth in stem length, and that shade-adapted species are more likely to be more synchronous between increases in individual leaf area (ILA) (leaf size) and leaf number (LN) during twig development compared with sun-adapted species, giving priority to growth of leaf size. We tested these two hypotheses by recording the phenologies of leaf emergence, leaf expansion and stem elongation during twig development for 19 evergreen woody species (including five shade-adapted understory species, six sun-adapted understory species and eight sun-adapted canopy species) in a subtropical evergreen broad-leaved forest in eastern China. We constructed indices to characterize the synchronicity between TLA and stem length (αLS) and between leaf size and leaf number (αSN) and we derived the α values from logistic functions taking the general form of A = A(max)/[1 + exp(β - αB)] (where A is the TLA or average ILA, B is the corresponding stem length or LN at a specific time, and A(max) is the maximum TLA or the maximum ILA of a twig; the higher the numerical value of α, the less synchronous the corresponding phenologies). Consistent with our hypotheses, sun-adapted species were higher both in α(LS) and α(SN), showing less synchronous patterns in the growths of TLA vs stem length and leaf size vs LN during twig development. Moreover, α(LS) and α(SN) were significantly positively correlated with relative growth rates of LN and leaf size across species, as indicated by both analyses of ordinary regression and phylogenetic generalized least squares. The across-species synchronies during twig development show that the temporal dynamics of the leaf size-twig size spectrum is of adaptive significance in plants. We suggest that temporal dynamics of plant functional traits should be extensively studied to characterize plant life history. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Comparing capacity coefficient and dual task assessment of visual multitasking workload
DOE Office of Scientific and Technical Information (OSTI.GOV)
Blaha, Leslie M.
Capacity coefficient analysis could offer a theoretically grounded alternative approach to subjective measures and dual task assessment of cognitive workload. Workload capacity or workload efficiency is a human information processing modeling construct defined as the amount of information that can be processed by the visual cognitive system given a specified of amount of time. In this paper, I explore the relationship between capacity coefficient analysis of workload efficiency and dual task response time measures. To capture multitasking performance, I examine how the relatively simple assumptions underlying the capacity construct generalize beyond the single visual decision making tasks. The fundamental toolsmore » for measuring workload efficiency are the integrated hazard and reverse hazard functions of response times, which are defined by log transforms of the response time distribution. These functions are used in the capacity coefficient analysis to provide a functional assessment of the amount of work completed by the cognitive system over the entire range of response times. For the study of visual multitasking, capacity coefficient analysis enables a comparison of visual information throughput as the number of tasks increases from one to two to any number of simultaneous tasks. I illustrate the use of capacity coefficients for visual multitasking on sample data from dynamic multitasking in the modified Multi-attribute Task Battery.« less
Partially Disordered Phase in Frustrated Triangular Lattice Antiferromagnet CuFeO 2
NASA Astrophysics Data System (ADS)
Mitsuda, Setsuo; Kasahara, Noriaki; Uno, Takahiro; Mase, Motoshi
1998-12-01
We reinvestigated successive magnetic phase transitions (T N1˜14.0 K, T N2˜10.5 K) in a frustrated triangular lattice antiferromagnet (TLA) CuFeO2 by neutron diffraction measurements using single crystals. The magnetic structure of the intermediate-temperature phase between T N1 and T N2 is found to be a quasi-long range ordered sinusoidally amplitude-modulated structure with a temperature dependent propagation wave vector (q q 0). These features of successive phase transitions are well explained by reinvestigated Monte-Carlo simulation of a 2D Ising TLA with competing exchange interactions up to 3rd neighbors, in spite of the Heisenberg spin character of orbital singlet Fe3+ magnetic ions.
NASA Astrophysics Data System (ADS)
Mitsuda, Setsuo; Mase, Motoshi; Prokes, K.; Kitazawa, Hideaki; Katori, H.
2000-11-01
Neutron diffraction studies on a frustrated triangular lattice antiferromagnet (TLA) CuFeO2 have been performed under an applied magnetic field up to 14.5 T. The first-field-induced state was found to be not the commensurate 5-sublattice (↑↑↑↓↓) magnetic state but rather an incommensurate complex helical state reflecting the Heisenberg spin character of orbital singlet Fe3+ magnetic ions. In contrast, the second-field-induced state was found to be the 5-sublattice (↑↑↑↓↓) magnetic state predicted by the two-dimensional (2D) Ising spin TLA model with competing exchange interactions up to the 3rd neighbors.
Acid extraction by supported liquid membranes containing basic carriers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Danesi, P.R.; Cianetti, C.; Horwitz, E.P.
1983-01-01
The extraction of HNO/sub 3/ (nitric acid) from aqueous solutions by permeation through a number of supported liquid membranes containing basic carriers dissolved in diethylbenzene has been studied. The results have shown that the best permeations are obtained with long chain aliphatic amines (TLA, Primene JM-T) followed by TOPO (trioctylphosphine oxide) and then by other monofunctional and bifunctional organophosphorous basic carriers. The influence of an aliphatic diluent on the permeability of HNO/sub 3/ through a supported liquid membrane containing TLA as carrier was also investigated. In this case the permeability to HNO/sub 3/ decreases as a result of the lowermore » diffusion coefficient of the acid-carrier complex in the more vicous aliphatic solvent. 4 figures.« less
Voice measures of workload in the advanced flight deck: Additional studies
NASA Technical Reports Server (NTRS)
Schneider, Sid J.; Alpert, Murray
1989-01-01
These studies investigated acoustical analysis of the voice as a measure of workload in individual operators. In the first study, voice samples were recorded from a single operator during high, medium, and low workload conditions. Mean amplitude, frequency, syllable duration, and emphasis all tended to increase as workload increased. In the second study, NASA test pilots performed a laboratory task, and used a flight simulator under differing work conditions. For two of the pilots, high workload in the simulator brought about greater amplitude, peak duration, and stress. In both the laboratory and simulator tasks, high workload tended to be associated with more statistically significant drop-offs in the acoustical measures than were lower workload levels. There was a great deal of intra-subject variability in the acoustical measures. The results suggested that in individual operators, increased workload might be revealed by high initial amplitude and frequency, followed by rapid drop-offs over time.
A self-analysis of the NASA-TLX workload measure.
Noyes, Jan M; Bruneau, Daniel P J
2007-04-01
Computer use and, more specifically, the administration of tests and materials online continue to proliferate. A number of subjective, self-report workload measures exist, but the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) is probably the most well known and used. The aim of this paper is to consider the workload costs associated with the computer-based and paper versions of the NASA-TLX measure. It was found that there is a significant difference between the workload scores for the two media, with the computer version of the NASA-TLX incurring more workload. This has implications for the practical use of the NASA-TLX as well as for other computer-based workload measures.
A Project Team Analysis Using Tuckman's Model of Small-Group Development.
Natvig, Deborah; Stark, Nancy L
2016-12-01
Concerns about equitable workloads for nursing faculty have been well documented, yet a standardized system for workload management does not exist. A project team was challenged to establish an academic workload management system when two dissimilar universities were consolidated. Tuckman's model of small-group development was used as the framework for the analysis of processes and effectiveness of a workload project team. Agendas, notes, and meeting minutes were used as the primary sources of information. Analysis revealed the challenges the team encountered. Utilization of a team charter was an effective tool in guiding the team to become a highly productive group. Lessons learned from the analysis are discussed. Guiding a diverse group into a highly productive team is complex. The use of Tuckman's model of small-group development provided a systematic mechanism to review and understand group processes and tasks. [J Nurs Educ. 2016;55(12):675-681.]. Copyright 2016, SLACK Incorporated.
Pilot workload and fatigue: A critical survey of concepts and assessment techniques
NASA Technical Reports Server (NTRS)
Gartner, W. B.; Murphy, M. R.
1976-01-01
The principal unresolved issues in conceptualizing and measuring pilot workload and fatigue are discussed. These issues are seen as limiting the development of more useful working concepts and techniques and their application to systems engineering and management activities. A conceptual analysis of pilot workload and fatigue, an overview and critique of approaches to the assessment of these phenomena, and a discussion of current trends in the management of unwanted workload and fatigue effects are presented. Refinements and innovations in assessment methods are recommended for enhancing the practical significance of workload and fatigue studies.
Adaptation of time line analysis program to single pilot instrument flight research
NASA Technical Reports Server (NTRS)
Hinton, D. A.; Shaughnessy, J. D.
1978-01-01
A data base was developed for SPIFR operation and the program was run. The outputs indicated that further work was necessary on the workload models. In particular, the workload model for the cognitive channel should be modified as the output workload appears to be too small. Included in the needed refinements are models to show the workload when in turbulence, when overshooting a radial or glideslope, and when copying air traffic control clearances.
Analysis of the workload of bank tellers of a Brazilian public institution.
Serikawa, Simoni S; Albieri, Ana Carolina S; Bonugli, Gustavo P; Greghi, Marina F
2012-01-01
During the last decades there have been many changes in the banking sector organization. It has been also observed the mutual growing of musculoskeletal and mental disorders. This study investigated the workload of bank tellers at a Brazilian public institution. It was performed the Ergonomic Work Analysis (EWA). Three employees participated in this study. During the analysis process, three research instruments were applied: Inventory of Work and Risk of Illness, Yoshitake Fatigue Questionnaire and Nordic Musculoskeletal Questionnaire, beyond the realization of footage recordings and the self-confrontation. The results indicated the existence of an excess of workload on the evaluated workstations, mainly in relation to mental order constraints, that overlaps the physical aspects. Thereby it was found that the employees tend to adopt strategies trying to reduce the impacts of the excess of workload, in order to regulate it.
Scaling Deep Learning Workloads: NVIDIA DGX-1/Pascal and Intel Knights Landing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gawande, Nitin A.; Landwehr, Joshua B.; Daily, Jeffrey A.
Deep Learning (DL) algorithms have become ubiquitous in data analytics. As a result, major computing vendors --- including NVIDIA, Intel, AMD and IBM --- have architectural road-maps influenced by DL workloads. Furthermore, several vendors have recently advertised new computing products as accelerating DL workloads. Unfortunately, it is difficult for data scientists to quantify the potential of these different products. This paper provides a performance and power analysis of important DL workloads on two major parallel architectures: NVIDIA DGX-1 (eight Pascal P100 GPUs interconnected with NVLink) and Intel Knights Landing (KNL) CPUs interconnected with Intel Omni-Path. Our evaluation consists of amore » cross section of convolutional neural net workloads: CifarNet, CaffeNet, AlexNet and GoogleNet topologies using the Cifar10 and ImageNet datasets. The workloads are vendor optimized for each architecture. GPUs provide the highest overall raw performance. Our analysis indicates that although GPUs provide the highest overall performance, the gap can close for some convolutional networks; and KNL can be competitive when considering performance/watt. Furthermore, NVLink is critical to GPU scaling.« less
An analysis of scatter decomposition
NASA Technical Reports Server (NTRS)
Nicol, David M.; Saltz, Joel H.
1990-01-01
A formal analysis of a powerful mapping technique known as scatter decomposition is presented. Scatter decomposition divides an irregular computational domain into a large number of equal sized pieces, and distributes them modularly among processors. A probabilistic model of workload in one dimension is used to formally explain why, and when scatter decomposition works. The first result is that if correlation in workload is a convex function of distance, then scattering a more finely decomposed domain yields a lower average processor workload variance. The second result shows that if the workload process is stationary Gaussian and the correlation function decreases linearly in distance until becoming zero and then remains zero, scattering a more finely decomposed domain yields a lower expected maximum processor workload. Finally it is shown that if the correlation function decreases linearly across the entire domain, then among all mappings that assign an equal number of domain pieces to each processor, scatter decomposition minimizes the average processor workload variance. The dependence of these results on the assumption of decreasing correlation is illustrated with situations where a coarser granularity actually achieves better load balance.
Critical anisotropies of a geometrically frustrated triangular-lattice antiferromagnet
NASA Astrophysics Data System (ADS)
Swanson, M.; Haraldsen, J. T.; Fishman, R. S.
2009-05-01
This work examines the critical anisotropy required for the local stability of the collinear ground states of a geometrically frustrated triangular-lattice antiferromagnet (TLA). Using a Holstein-Primakoff expansion, we calculate the spin-wave frequencies for the one-, two-, three-, four-, and eight-sublattice (SL) ground states of a TLA with up to third neighbor interactions. Local stability requires that all spin-wave frequencies are real and positive. The two-, four-, and eight-SL phases break up into several regions where the critical anisotropy is a different function of the exchange parameters. We find that the critical anisotropy is a continuous function everywhere except across the two-SL/three-SL and three-SL/four-SL phase boundaries, where the three-SL phase has the higher critical anisotropy.
Critical Anisotropies of a Geometrically-Frustrated Triangular-Lattice
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swanson, Mason R; Haraldsen, Jason T; Fishman, Randy Scott
2009-01-01
This work examines the critical anisotropy required for the local stability of the collinear ground states of a geometrically-frustrated triangular-lattice antiferromagnet (TLA). Using a Holstein-Primakoff expansion, we calculate the spin-wave frequencies for the 1, 2, 3, 4, and 8-sublattice (SL) ground states of a TLA with up to third neighbor interactions. Local stability requires that all spin-wave frequencies are real and positive. The 2, 4, and 8-SL phases break up into several regions where the critical anisotropy is a different function of the exchange parameters. We find that the critical anisotropy is a continuous function everywhere except across the 2-SL/3-SLmore » and 3-SL/4-SL phase boundaries, where the 3-SL phase has the higher critical anisotropy.« less
Flight Crew Workload Evaluation Based on the Workload Function Distribution Method.
Zheng, Yiyuan; Lu, Yanyu; Jie, Yuwen; Fu, Shan
2017-05-01
The minimum flight crew on the flight deck should be established according to the workload for individual crewmembers. Typical workload measures consist of three types: subjective rating scale, task performance, and psychophysiological measures. However, all these measures have their own limitations. To reflect flight crew workload more specifically and comprehensively within the flight environment, and more directly comply with airworthiness regulations, the Workload Function Distribution Method, which combined the basic six workload functions, was proposed. The analysis was based on the different conditions of workload function numbers. Each condition was analyzed from two aspects, which were overall proportion and effective proportion. Three types of approach tasks were used in this study and the NASA-TLX scale was implemented for comparison. Neither the one-function condition nor the two-function condition had the same results with NASA-TLX. However, both the three-function and the four- to six- function conditions were identical with NASA-TLX. Further, the significant differences were different on four to six conditions. The overall proportion was insignificant, while the effective proportions were significant. The results show that the conditions with one function and two functions seemed to have no influence on workload, while executing three functions and four to six functions had an impact on workload. Besides, effective proportions of workload functions were more precisely compared with the overall proportions to indicate workload, especially in the conditions with multiple functions.Zheng Y, Lu Y, Jie Y, Fu S. Flight crew workload evaluation based on the workload function distribution method. Aerosp Med Hum Perform. 2017; 88(5):481-486.
MEASURING WORKLOAD OF ICU NURSES WITH A QUESTIONNAIRE SURVEY: THE NASA TASK LOAD INDEX (TLX).
Hoonakker, Peter; Carayon, Pascale; Gurses, Ayse; Brown, Roger; McGuire, Kerry; Khunlertkit, Adjhaporn; Walker, James M
2011-01-01
High workload of nurses in Intensive Care Units (ICUs) has been identified as a major patient safety and worker stress problem. However, relative little attention has been dedicated to the measurement of workload in healthcare. The objectives of this study are to describe and examine several methods to measure workload of ICU nurses. We then focus on the measurement of ICU nurses' workload using a subjective rating instrument: the NASA TLX.We conducted secondary data analysis on data from two, multi-side, cross-sectional questionnaire studies to examine several instruments to measure ICU nurses' workload. The combined database contains the data from 757 ICU nurses in 8 hospitals and 21 ICUs.Results show that the different methods to measure workload of ICU nurses, such as patient-based and operator-based workload, are only moderately correlated, or not correlated at all. Results show further that among the operator-based instruments, the NASA TLX is the most reliable and valid questionnaire to measure workload and that NASA TLX can be used in a healthcare setting. Managers of hospitals and ICUs can benefit from the results of this research as it provides benchmark data on workload experienced by nurses in a variety of ICUs.
MEASURING WORKLOAD OF ICU NURSES WITH A QUESTIONNAIRE SURVEY: THE NASA TASK LOAD INDEX (TLX)
Hoonakker, Peter; Carayon, Pascale; Gurses, Ayse; Brown, Roger; McGuire, Kerry; Khunlertkit, Adjhaporn; Walker, James M.
2012-01-01
High workload of nurses in Intensive Care Units (ICUs) has been identified as a major patient safety and worker stress problem. However, relative little attention has been dedicated to the measurement of workload in healthcare. The objectives of this study are to describe and examine several methods to measure workload of ICU nurses. We then focus on the measurement of ICU nurses’ workload using a subjective rating instrument: the NASA TLX. We conducted secondary data analysis on data from two, multi-side, cross-sectional questionnaire studies to examine several instruments to measure ICU nurses’ workload. The combined database contains the data from 757 ICU nurses in 8 hospitals and 21 ICUs. Results show that the different methods to measure workload of ICU nurses, such as patient-based and operator-based workload, are only moderately correlated, or not correlated at all. Results show further that among the operator-based instruments, the NASA TLX is the most reliable and valid questionnaire to measure workload and that NASA TLX can be used in a healthcare setting. Managers of hospitals and ICUs can benefit from the results of this research as it provides benchmark data on workload experienced by nurses in a variety of ICUs. PMID:22773941
A computerized multidimensional measurement of mental workload via handwriting analysis.
Luria, Gil; Rosenblum, Sara
2012-06-01
The goal of this study was to test the effect of mental workload on handwriting behavior and to identify characteristics of low versus high mental workload in handwriting. We hypothesized differences between handwriting under three different load conditions and tried to establish a profile that integrated these indicators. Fifty-six participants wrote three numerical progressions of varying difficulty on a digitizer attached to a computer so that we could evaluate their handwriting behavior. Differences were found in temporal, spatial, and angular velocity handwriting measures, but no significant differences were found for pressure measures. Using data reduction, we identified three clusters of handwriting, two of which differentiated well according to the three mental workload conditions. We concluded that handwriting behavior is affected by mental workload and that each measure provides distinct information, so that they present a comprehensive indicator of mental workload.
Strategic workload management and decision biases in aviation
NASA Technical Reports Server (NTRS)
Raby, Mireille; Wickens, Christopher D.
1994-01-01
Thirty pilots flew three simulated landing approaches under conditions of low, medium, and high workload. Workload conditions were created by varying time pressure and external communications requirements. Our interest was in how the pilots strategically managed or adapted to the increasing workload. We independently assessed the pilot's ranking of the priority of different discrete tasks during the approach and landing. Pilots were found to sacrifice some aspects of primary flight control as workload increased. For discrete tasks, increasing workload increased the amount of time in performing the high priority tasks, decreased the time in performing those of lowest priority, and did not affect duration of performance episodes or optimality of scheduling of tasks of any priority level. Individual differences analysis revealed that high-performing subjects scheduled discrete tasks earlier in the flight and shifted more often between different activities.
Structural characteristics of Tla products
1985-01-01
Biochemical study of thymus leukemia antigen (TL) from thymocytes of various Tla genotypes and from leukemia cells revealed features that, given present evidence, are peculiar to TL among class I products of the H-2:Qa:Tla region of chromosome 17. Sodium dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE) of TL from thymocytes of all TL+ mouse strains, precipitated by anti-TL antiserum or monoclonal antibodies, showed two closely migrating bands of equal intensity in the heavy (H) chain position (45-50,000 mol wt). Comparison of these two bands by two-dimensional isoelectric focusing (2D IEF)-SDS-PAGE and 2D chymotryptic peptide mapping showed no differences indicative of protein dissimilarity. Thus, the two components of the H chain doublet may differ only in a feature of glycosylation that does not affect charge. The two leukemias studied gave only a single band in the H chain position. On 2D peptide mapping and 2D IEF-SDS-PAGE, the patterns for TL of Tlaa and Tlae thymocytes, which are closely related serologically, were broadly similar, but clearly different from the pattern typical of Tlac and Tlad thymocytes. 2D peptide maps of TL from Tlaa thymocytes and Tlaa leukemia cells did not differ. Leukemia cells of Tlab origin (thymocytes TL-) gave 2D peptide and 2D IEF-SDS-PAGE patterns of a third type. With the exception of Tlaa, thymocytes of TL+ mice yielded additional TL products of higher molecular weight than the TL H chain. PMID:3875681
Twentieth Annual Conference on Manual Control, Volume 2
NASA Technical Reports Server (NTRS)
Hart, S. G. (Compiler); Hartzell, E. J. (Compiler)
1984-01-01
Volume II contains thirty two complete manuscripts and five abstracts. The topics covered include the application of event-related brain potential analysis to operational problems, the subjective evaluation of workload, mental models, training, crew interaction analysis, multiple task performance, and the measurement of workload and performance in simulation.
Ion beam methods applied to interior ballistic studies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Niler, A.
1981-04-01
High temperature, pressure and velocity gases produced during the interior ballistic cycle of a gun firing are responsible for considerable damage to the steel surfaces of a gun bore. This damage is studied by exposing steel samples to the erosive flows of burning propellant gases in a modified 37mm gun chamber where pressures of 200 MPa and flame temperatures of 3000/sup 0/K are typical. Ion beam methods are used to characterize the composition of the steel surfaces by combined nuclear reaction (NR) and elastic backscattering (EBS) analysis and thin layer activation (TLA) is used to measure surface wear rates. Combinedmore » fits to the EBS and NR distributions yield concentrations and depth profiles of carbon, nitrogen and oxygen as well as iron and other heavier elements. Hydrogen concentrations have also been measured on some of the samples. The results of these experiments show the presence of two different erosion mechanisms. In one, the surface is softened by thermo-chemical processes prior to removal by the shear forces of the gas flow while in the other surface layer melting occurs prior to removal. TLA using the /sup 56/Fe(p,n)/sup 56/Co reaction has been used to measure wear from a 20 mm barrel and is being instrumented for larger barrels. EBS is being used to characterize the interfaces between steel substrates and coatings designed to reduce erosion.« less
Holden, Richard J.; Scanlon, Matthew C.; Patel, Neal R.; Kaushal, Rainu; Escoto, Kamisha Hamilton; Brown, Roger L.; Alper, Samuel J.; Arnold, Judi M.; Shalaby, Theresa M.; Murkowski, Kathleen; Karsh, Ben-Tzion
2010-01-01
Backgrounds Nursing workload is increasingly thought to contribute to both nurses’ quality of working life and quality/safety of care. Prior studies lack a coherent model for conceptualizing and measuring the effects of workload in health care. In contrast, we conceptualized a human factors model for workload specifying workload at three distinct levels of analysis and having multiple nurse and patient outcomes. Methods To test this model, we analyzed results from a cross-sectional survey of a volunteer sample of nurses in six units of two academic tertiary care pediatric hospitals. Results Workload measures were generally correlated with outcomes of interest. A multivariate structural model revealed that: the unit-level measure of staffing adequacy was significantly related to job dissatisfaction (path loading = .31) and burnout (path loading = .45); the task-level measure of mental workload related to interruptions, divided attention, and being rushed was associated with burnout (path loading = .25) and medication error likelihood (path loading = 1.04). Job-level workload was not uniquely and significantly associated with any outcomes. Discussion The human factors engineering model of nursing workload was supported by data from two pediatric hospitals. The findings provided a novel insight into specific ways that different types of workload could affect nurse and patient outcomes. These findings suggest further research and yield a number of human factors design suggestions. PMID:21228071
Holden, Richard J; Scanlon, Matthew C; Patel, Neal R; Kaushal, Rainu; Escoto, Kamisha Hamilton; Brown, Roger L; Alper, Samuel J; Arnold, Judi M; Shalaby, Theresa M; Murkowski, Kathleen; Karsh, Ben-Tzion
2011-01-01
Nursing workload is increasingly thought to contribute to both nurses' quality of working life and quality/safety of care. Prior studies lack a coherent model for conceptualising and measuring the effects of workload in healthcare. In contrast, we conceptualised a human factors model for workload specifying workload at three distinct levels of analysis and having multiple nurse and patient outcomes. To test this model, we analysed results from a cross-sectional survey of a volunteer sample of nurses in six units of two academic tertiary care paediatric hospitals. Workload measures were generally correlated with outcomes of interest. A multivariate structural model revealed that: the unit-level measure of staffing adequacy was significantly related to job dissatisfaction (path loading=0.31) and burnout (path loading=0.45); the task-level measure of mental workload related to interruptions, divided attention, and being rushed was associated with burnout (path loading=0.25) and medication error likelihood (path loading=1.04). Job-level workload was not uniquely and significantly associated with any outcomes. The human factors engineering model of nursing workload was supported by data from two paediatric hospitals. The findings provided a novel insight into specific ways that different types of workload could affect nurse and patient outcomes. These findings suggest further research and yield a number of human factors design suggestions.
Measurement, Modeling, and Analysis of a Large-scale Blog Sever Workload
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeon, Myeongjae; Hwang, Jeaho; Kim, Youngjae
2010-01-01
Despite the growing popularity of Online Social Networks (OSNs), the workload characteristics of OSN servers, such as those hosting blog services, are not well understood. Understanding workload characteristics is important for opti- mizing and improving the performance of current systems and software based on observed trends. Thus, in this paper, we characterize the system workload of the largest blog hosting servers in South Korea, Tistory1. In addition to understanding the system workload of the blog hosting server, we have developed synthesized workloads and obtained the following major findings: (i) the transfer size of non-multimedia files and blog articles can bemore » modeled by a truncated Pareto distribution and a log-normal distribution respectively, and (ii) users accesses to blog articles do not show temporal locality, but they are strongly biased toward those posted along with images or audio.« less
Using Psychophysiological Sensors to Assess Mental Workload During Web Browsing.
Jimenez-Molina, Angel; Retamal, Cristian; Lira, Hernan
2018-02-03
Knowledge of the mental workload induced by a Web page is essential for improving users' browsing experience. However, continuously assessing the mental workload during a browsing task is challenging. To address this issue, this paper leverages the correlation between stimuli and physiological responses, which are measured with high-frequency, non-invasive psychophysiological sensors during very short span windows. An experiment was conducted to identify levels of mental workload through the analysis of pupil dilation measured by an eye-tracking sensor. In addition, a method was developed to classify mental workload by appropriately combining different signals (electrodermal activity (EDA), electrocardiogram, photoplethysmo-graphy (PPG), electroencephalogram (EEG), temperature and pupil dilation) obtained with non-invasive psychophysiological sensors. The results show that the Web browsing task involves four levels of mental workload. Also, by combining all the sensors, the efficiency of the classification reaches 93.7%.
Using Psychophysiological Sensors to Assess Mental Workload During Web Browsing
Jimenez-Molina, Angel; Retamal, Cristian; Lira, Hernan
2018-01-01
Knowledge of the mental workload induced by a Web page is essential for improving users’ browsing experience. However, continuously assessing the mental workload during a browsing task is challenging. To address this issue, this paper leverages the correlation between stimuli and physiological responses, which are measured with high-frequency, non-invasive psychophysiological sensors during very short span windows. An experiment was conducted to identify levels of mental workload through the analysis of pupil dilation measured by an eye-tracking sensor. In addition, a method was developed to classify mental workload by appropriately combining different signals (electrodermal activity (EDA), electrocardiogram, photoplethysmo-graphy (PPG), electroencephalogram (EEG), temperature and pupil dilation) obtained with non-invasive psychophysiological sensors. The results show that the Web browsing task involves four levels of mental workload. Also, by combining all the sensors, the efficiency of the classification reaches 93.7%. PMID:29401688
Effect of Dynamic Sector Boundary Changes on Air Traffic Controllers
NASA Technical Reports Server (NTRS)
Jung, Jaewoo; Lee, Paul; Kessell, Angela; Homola, Jeff; Zelinski, Shannon
2010-01-01
The effect of dynamic sector boundary changes on air traffic controller workload was investigated with data from a human-in-the-loop simulation. Multiple boundary changes were made during simulated operations, and controller rating of workload was recorded. Analysis of these data showed an increase of 16.9% in controller workload due to boundary changes. This increased workload was correlated with the number of aircraft handoffs and change in sector volume. There was also a 12.7% increase in average workload due to the changed sector design after boundary changes. This increase was correlated to traffic flow crossing points getting closer to sector boundaries and an increase in the number of flights with short dwell time in a sector. This study has identified some of the factors that affect controller workload when sector boundaries are changed, but more research is needed to better understand their relationships.
Analysis of Different Cost Functions in the Geosect Airspace Partitioning Tool
NASA Technical Reports Server (NTRS)
Wong, Gregory L.
2010-01-01
A new cost function representing air traffic controller workload is implemented in the Geosect airspace partitioning tool. Geosect currently uses a combination of aircraft count and dwell time to select optimal airspace partitions that balance controller workload. This is referred to as the aircraft count/dwell time hybrid cost function. The new cost function is based on Simplified Dynamic Density, a measure of different aspects of air traffic controller workload. Three sectorizations are compared. These are the current sectorization, Geosect's sectorization based on the aircraft count/dwell time hybrid cost function, and Geosect s sectorization based on the Simplified Dynamic Density cost function. Each sectorization is evaluated for maximum and average workload along with workload balance using the Simplified Dynamic Density as the workload measure. In addition, the Airspace Concept Evaluation System, a nationwide air traffic simulator, is used to determine the capacity and delay incurred by each sectorization. The sectorization resulting from the Simplified Dynamic Density cost function had a lower maximum workload measure than the other sectorizations, and the sectorization based on the combination of aircraft count and dwell time did a better job of balancing workload and balancing capacity. However, the current sectorization had the lowest average workload, highest sector capacity, and the least system delay.
Activity-based differentiation of pathologists' workload in surgical pathology.
Meijer, G A; Oudejans, J J; Koevoets, J J M; Meijer, C J L M
2009-06-01
Adequate budget control in pathology practice requires accurate allocation of resources. Any changes in types and numbers of specimens handled or protocols used will directly affect the pathologists' workload and consequently the allocation of resources. The aim of the present study was to develop a model for measuring the pathologists' workload that can take into account the changes mentioned above. The diagnostic process was analyzed and broken up into separate activities. The time needed to perform these activities was measured. Based on linear regression analysis, for each activity, the time needed was calculated as a function of the number of slides or blocks involved. The total pathologists' time required for a range of specimens was calculated based on standard protocols and validated by comparing to actually measured workload. Cutting up, microscopic procedures and dictating turned out to be highly correlated to number of blocks and/or slides per specimen. Calculated workload per type of specimen was significantly correlated to the actually measured workload. Modeling pathologists' workload based on formulas that calculate workload per type of specimen as a function of the number of blocks and slides provides a basis for a comprehensive, yet flexible, activity-based costing system for pathology.
Application and Validation of Workload Assessment Techniques
1993-03-01
tech ical report documents the process and outcome of meeting this objective. Procedure: A series of eight separate studies was conducted using three...development process . The task analysis and simulation technique was shown to have the capability to track empirical workload ratings. More research is...operator workload during the systems acquisi- tion process , and (b) a pamphlet for the managers of Army systems that describes the need and some procedures
Voice-stress measure of mental workload
NASA Technical Reports Server (NTRS)
Alpert, Murray; Schneider, Sid J.
1988-01-01
In a planned experiment, male subjects between the age of 18 and 50 will be required to produce speech while performing various tasks. Analysis of the speech produced should reveal which aspects of voice prosody are associated with increased workloads. Preliminary results with two female subjects suggest a possible trend for voice frequency and amplitude to be higher and the variance of the voice frequency to be lower in the high workload condition.
Scaling deep learning workloads: NVIDIA DGX-1/Pascal and Intel Knights Landing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gawande, Nitin A.; Landwehr, Joshua B.; Daily, Jeffrey A.
Deep Learning (DL) algorithms have become ubiquitous in data analytics. As a result, major computing vendors --- including NVIDIA, Intel, AMD, and IBM --- have architectural road-maps influenced by DL workloads. Furthermore, several vendors have recently advertised new computing products as accelerating large DL workloads. Unfortunately, it is difficult for data scientists to quantify the potential of these different products. This paper provides a performance and power analysis of important DL workloads on two major parallel architectures: NVIDIA DGX-1 (eight Pascal P100 GPUs interconnected with NVLink) and Intel Knights Landing (KNL) CPUs interconnected with Intel Omni-Path or Cray Aries. Ourmore » evaluation consists of a cross section of convolutional neural net workloads: CifarNet, AlexNet, GoogLeNet, and ResNet50 topologies using the Cifar10 and ImageNet datasets. The workloads are vendor-optimized for each architecture. Our analysis indicates that although GPUs provide the highest overall performance, the gap can close for some convolutional networks; and the KNL can be competitive in performance/watt. We find that NVLink facilitates scaling efficiency on GPUs. However, its importance is heavily dependent on neural network architecture. Furthermore, for weak-scaling --- sometimes encouraged by restricted GPU memory --- NVLink is less important.« less
Alvarez, Ana Graziela; Sasso, Grace; Iyengar, Sriram
2015-11-06
The inclusion of new technologies in education has motivated the development of studies on mental workload. These technologies are now being used in the teaching and learning process. The analysis enables identification of factors intervening in this workload as well as planning of overload prevention for educational activities using these technologies. To analyze the mental workload of an educational intervention with the Mobile Virtual Learning Object for the Assessment of Acute Pain in adults and newborns, according to the NASA Task Load Index criteria. A methodological study with data collected from 5 nurses and 75 students, from November of 2013 to February of 2014. The highest students' and specialists' means were in the dimensions of "Mental demand" (57.20 ± 22.27; 51 ± 29.45) and "Performance" (58.47 ± 24.19; 73 ± 28.85). The specialists' mental workload index was higher (50.20 ± 7.28) when compared with students' (47.87 ± 16.85) on a scale from 0 to 100 (P=.557). The instrument allowed for the assessment of mental workload after an online educational intervention with a mobile learning virtual object. An excessive overload was not identified among participants. Assessing mental workload from the use of educational technologies at the end of a task is a key to their applicability, with the aim of providing a more effective, stimulating, and long-lasting experience of the learning process.
NASA Astrophysics Data System (ADS)
Hermanne, A.; Sonck, M.; Takács, S.; Szelecsényi, F.; Tárkányi, F.
1999-05-01
Excitation functions for the reactions induced by alpha particles on natTi foils and leading to the formation of 44m,44g,46,47,48Sc; 48,51Cr and 48V were determined using the stacked foil technique for energies from the respective reaction thresholds up to 42 MeV. The new experimental values are compared to earlier literature values and generally good accordance is found. It appears that the natTi(α,x) 51Cr reaction is particularly useful for monitoring α-beams in the 10-20 MeV region while for energies above 20 MeV the natTi(α,x) 47Sc reaction or the natTi(α,x) 48V reaction are more suited. The excitation functions established can be used to determine calibration curves for thin layer activation (TLA) as well.
NASA Astrophysics Data System (ADS)
Ren, Y.; Ye, F.; Huang, Q.; Fernandez-Baca, J. A.; Dai, Pengcheng; Lynn, J. W.; Kimura, T.
2006-03-01
We use high resolution synchrotron X-ray and neutron diffraction to study the geometrically frustrated triangular lattice antiferromagnet (TLA) CuFeO2. We show that the occurrence of the two magnetic transitions, at 14 K and 11 K, respectively is accompanied simultaneously by a second-and first- order structural phase transitions from a hexagonal structure to a monoclinic form. This is the first observation of two successive spin-driven structural transitions directly coupled with incommensurate and commensurate magnetic orderings in frustrated TLA systems. This work is supported by the U. S. NSF DMR-0453804 and DOE Nos. DE-FG02-05ER46202 and DE-AC05-00OR22725 with UT/Battelle LLC. Use of the Advanced Photon Source was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. W-31-109-Eng-38.
Crew procedures for microwave landing system operations
NASA Technical Reports Server (NTRS)
Summers, Leland G.
1987-01-01
The objective of this study was to identify crew procedures involved in Microwave Landing System (MLS) operations and to obtain a preliminary assessment of crew workload. The crew procedures were identified for three different complements of airborne equipment coupled to an autopilot. Using these three equipment complements, crew tasks were identified for MLS approaches and precision departures and compared to an ILS approach and a normal departure. Workload comparisons between the approaches and departures were made by using a task-timeline analysis program that obtained workload indexes, i.e., the radio of time required to complete the tasks to the time available. The results showed an increase in workload for the MLS scenario for one of the equipment complements. However, even this workload was within the capacity of two crew members.
Driver distraction : eye glance analysis and conversation workload : [research brief].
DOT National Transportation Integrated Search
2015-11-01
The objective of this project was to: : Assess the risk of performing a secondary task : while driving a commercial motor vehicle (CMV). : Better understand the relationship of conversation : workload and visual distraction during mobile : ph...
Warner, John O
2017-04-01
Avoidance of allergens in the treatment of asthma has hitherto not achieved significant benefit despite the strong evidence that allergy both increases severity and contributes to exacerbations of asthma. House dust mite, cat and dog allergens are the most common perennial allergic triggers and most avoidance strategies have focused on reducing exposures in bedrooms. Cochrane reviews have suggested that they neither significantly reduce allergen levels nor improve asthma. While the lack of efficacy may be assumed to be a consequence of exposures occurring outside the bedroom, prolonged sleep is associated with increased susceptibility to bronchospasm and airway inflammation. Thus, if efficient reductions in allergen exposure could be achieved during sleep, it might be expected that this would result in significant improvements in control of asthma. The temperature-controlled laminar airflow (TLA) is a system which can be employed over beds in a domestic environment and results in massive reductions in particulate exposure of recumbent subjects, including highly respirable allergens such as Fel. D1 from cats. Trials of TLA have demonstrated highly significant improvements in asthma quality of life and reductions on airway inflammation as monitored by exhaled nitric oxide levels. Furthermore, in patients with the worst disease, severe exacerbation frequency was significantly reduced. Based on UK health-service costs, the use of TLA falls well below the National Institute for Health and Care Excellence (NICE) threshold for the incremental cost effectiveness ratio (ICER) per quality adjusted life year (QALY). Indeed, for those with frequent exacerbations, it is cost saving and should be prescribed for such allergic asthmatic patients.
Injections of Local Anesthetics into the Pharyngeal Region Reduce Trapezius Muscle Tenderness.
Weinschenk, Stefan; Hollmann, Markus W; Göllner, Richard; Picardi, Susanne; Strowitzki, Thomas; Diehl, Leon; Hotz, Lorenz; Meuser, Thomas
2016-01-01
Neck pain is a frequent reason for seeking medical advice. Neuroanatomical findings suggest a close connection between the pharynx and the trapezius region. Irritation of the pharynx may induce tenderness of this area. Specific tender points, called neck reflex points (NRPs), can be identified here with high reproducibility. We hypothesized that therapeutic local anesthesia (TLA; or neural therapy, NT) in the pharyngeal region can reduce tenderness in patients with therapy-resistant neck pain. 17 consecutive female patients with chronic cervical pain and positive trapezius NRPs received bilateral injections of 0.5 ml 1% procaine into the palatine velum. The NRPs were assessed using a 3-level pain index (PI = 0, 1, or 2) before and 3-5 min after each injection. We found a significant reduction in tenderness of the NRP of the trapezius region (NRP C7) immediately after TLA/NT. 30 positive NRPs were found before therapy and only 13 after therapy (p < 0.01). The average PI of the NRP C7 was 1.24 ± 0.77 before and 0.35 ± 0.59 after therapy (right side), and 1.34 ± 0.59 before and 0.59 ± 0.69 after therapy (left side). The pre- and post-therapy PI values were significantly different on both the right and left sides of the trapezius region (p < 0.01). No adverse effects were observed. Pharyngeal irritation may induce and maintain therapy-resistant cervical pain in patients with chronic pharyngeal disease. These patients could benefit from remote TLA/NT injections in the pharyngeal region. © 2016 S. Karger GmbH, Freiburg.
Smith, Nicholas G; Hoeppner, Susanne S; Dukes, Jeffrey S
2018-01-01
Abstract Predicting the effects of climate change on tree species and communities is critical for understanding the future state of our forested ecosystems. We used a fully factorial precipitation (three levels; ambient, −50 % ambient, +50 % ambient) by warming (four levels; up to +4 °C) experiment in an old-field ecosystem in the northeastern USA to study the climatic sensitivity of seedlings of six native tree species. We measured whole plant-level responses: survival, total leaf area (TLA), seedling insect herbivory damage, as well as leaf-level responses: specific leaf area (SLA), leaf-level water content (LWC), foliar nitrogen (N) concentration, foliar carbon (C) concentration and C:N ratio of each of these deciduous species in each treatment across a single growing season. We found that canopy warming dramatically increased the sensitivity of plant growth (measured as TLA) to rainfall across all species. Warm, dry conditions consistently reduced TLA and also reduced leaf C:N in four species (Acer rubrum, Betula lenta, Prunus serotina, Ulmus americana), primarily as a result of reduced foliar C, not increased foliar N. Interestingly, these conditions also harmed the other two species in different ways, increasing either mortality (Populus grandidentata) or herbivory (Quercus rubra). Specific leaf area and LWC varied across species, but did not show strong treatment responses. Our results indicate that, in the northeastern USA, dry years in a future warmer environment could have damaging effects on the growth capacity of these early secondary successional forests, through species-specific effects on leaf production (total leaves and leaf C), herbivory and mortality. PMID:29484151
NASA Astrophysics Data System (ADS)
Singh, Narayani P.; Zimmerman, Carol J.; Lewis, Laura L.; Wrenn, McDonald E.
1984-06-01
Solvent extraction and alpha-spectrometry have been emplyed in the quantitative simultaneous determination of uranium. thorium and plutonium. The bone specimens, spiked with 232U, 229Th and 242Pu tracers, are wet ashed with HNO 3 followed by alternate additions of a new drops of HNO 3 and H 2O 2. Uranium is reduced to the tetravalent state with 200 mg SnCl 2 and 25 ml HI. Uranium, thorium and plutonium are then coprecipitated with calcium as oxalate, heated to 550°C, dissolved in 50 ml HCl, and the acidity adjusted to 10 M. Uranium and plutonium are extracted into a 20% tri-lauryl amine (TLA) solution in xylene, leaving thorium in the aqueous phase. Plutonium is first back-extracted from the TLA phase by shaking with a 1:1.5 volume of 0.05 M NH 4I in 8 M HCl, which reduces Pu(IV) to Pu(III). Uranium is then back-extracted with an equal volume of 0.1 M HCl. Thorium, which was left in the aqueous phase, is evaporated to dryness, dissolved in 4 M HNO 3, and the acidity adjusted to 4 M. Thorium is then extracted into 20% TLA solution in xylene pre-equilibrated with 4 M HNO 3, and back-extracted with 10 M HCl. Uranium, thorium, and plutonium are then electrodeposited separately onto platinum discs and counted by an alpha-spectrometer with a multi-channel analyzer and surface barrier silicon diodes. The mean recoveries of uranium, thorium, and plutonium in bovine, dog, and human bones were over 70%.
Warner, John O.
2017-01-01
Avoidance of allergens in the treatment of asthma has hitherto not achieved significant benefit despite the strong evidence that allergy both increases severity and contributes to exacerbations of asthma. House dust mite, cat and dog allergens are the most common perennial allergic triggers and most avoidance strategies have focused on reducing exposures in bedrooms. Cochrane reviews have suggested that they neither significantly reduce allergen levels nor improve asthma. While the lack of efficacy may be assumed to be a consequence of exposures occurring outside the bedroom, prolonged sleep is associated with increased susceptibility to bronchospasm and airway inflammation. Thus, if efficient reductions in allergen exposure could be achieved during sleep, it might be expected that this would result in significant improvements in control of asthma. The temperature-controlled laminar airflow (TLA) is a system which can be employed over beds in a domestic environment and results in massive reductions in particulate exposure of recumbent subjects, including highly respirable allergens such as Fel. D1 from cats. Trials of TLA have demonstrated highly significant improvements in asthma quality of life and reductions on airway inflammation as monitored by exhaled nitric oxide levels. Furthermore, in patients with the worst disease, severe exacerbation frequency was significantly reduced. Based on UK health-service costs, the use of TLA falls well below the National Institute for Health and Care Excellence (NICE) threshold for the incremental cost effectiveness ratio (ICER) per quality adjusted life year (QALY). Indeed, for those with frequent exacerbations, it is cost saving and should be prescribed for such allergic asthmatic patients. PMID:28391760
Quantitative EEG patterns of differential in-flight workload
NASA Technical Reports Server (NTRS)
Sterman, M. B.; Mann, C. A.; Kaiser, D. A.
1993-01-01
Four test pilots were instrumented for in-flight EEG recordings using a custom portable recording system. Each flew six, two minute tracking tasks in the Calspan NT-33 experimental trainer at Edwards AFB. With the canopy blacked out, pilots used a HUD display to chase a simulated aircraft through a random flight course. Three configurations of flight controls altered the flight characteristics to achieve low, moderate, and high workload, as determined by normative Cooper-Harper ratings. The test protocol was administered by a command pilot in the back seat. Corresponding EEG and tracking data were compared off-line. Tracking performance was measured as deviation from the target aircraft and combined with control difficulty to achieve an estimate of 'cognitive workload'. Trended patterns of parietal EEG activity at 8-12 Hz were sorted according to this classification. In all cases, high workload produced a significantly greater suppression of 8-12 Hz activity than low workload. Further, a clear differentiation of EEG trend patterns was obtained in 80 percent of the cases. High workload produced a sustained suppression of 8-12 Hz activity, while moderate workload resulted in an initial suppression followed by a gradual increment. Low workload was associated with a modulated pattern lacking any periods of marked or sustained suppression. These findings suggest that quantitative analysis of appropriate EEG measures may provide an objective and reliable in-flight index of cognitive effort that could facilitate workload assessment.
NASA Technical Reports Server (NTRS)
Waller, M. C.
1976-01-01
An electro-optical device called an oculometer which tracks a subject's lookpoint as a time function has been used to collect data in a real-time simulation study of instrument landing system (ILS) approaches. The data describing the scanning behavior of a pilot during the instrument approaches have been analyzed by use of a stepwise regression analysis technique. A statistically significant correlation between pilot workload, as indicated by pilot ratings, and scanning behavior has been established. In addition, it was demonstrated that parameters derived from the scanning behavior data can be combined in a mathematical equation to provide a good representation of pilot workload.
Voice measures of workload in the advanced flight deck
NASA Technical Reports Server (NTRS)
Schneider, Sid J.; Alpert, Murray; Odonnell, Richard
1989-01-01
Voice samples were obtained from 14 male subjects under high and low workload conditions. Acoustical analysis of the voice suggested that high workload conditions can be revealed by their effects on the voice over time. Aircrews in the advanced flight deck will be voicing short, imperative sentences repeatedly. A drop in the energy of the voice, as reflected by reductions in amplitude and frequency over time, and the failure to achieve old amplitude and frequency levels after rest periods, can signal that the workload demands of the situation are straining the speaker. This kind of measurement would be relatively unaffected by individual differences in acoustical measures.
Ferra, Bartłomiej; Holec-Gąsior, Lucyna; Kur, Józef
2015-10-01
Toxoplasma gondii infects all warm-blooded animals including humans, causing serious public health problems and great economic loss in the animal husbandry. Commonly used serological tests for diagnosis of toxoplasmosis involve preparation of whole Toxoplasma lysate antigen (TLA) from tachyzoites. The production of this antigen is associated with high costs and lengthy preparation and the possibility of staff infection. There are also some difficulties in the standardization of such tests. One approach in order to improve the diagnosis of T. gondii infection is to use recombinant chimeric antigens in place of the TLA, which was confirmed by studies in the serodiagnosis of toxoplasmosis in humans. In this paper, we assess, for the first time, the diagnostic utility of five T. gondii recombinant chimeric antigens (MIC1-MAG1-SAG1S, SAG1L-MIC1-MAG1, SAG2-GRA1-ROP1S, SAG2-GRA1-ROP1L, and GRA1-GRA2-GRA6) in immunoglobulin G (IgG) enzyme-linked immunosorbent assays (IgG ELISAs) with sera from three different groups of livestock animals (horses, pigs, and sheep). The reactivity of individual chimeric antigens was analyzed in relation to the results obtained in IgG ELISAs based on a mixture of three antigens (M1: rSAG1+rMIC1+rMAG1, M2: rSAG2+rGRA1+rROP1, and M3: rGRA1+rGRA2+rGRA6) and referenced to TLA. All chimeric antigens were characterized by high specificity (100%), and the sensitivity of the IgG ELISAs based on chimeric antigens was variable (between 28.4% and 100%) and mainly dependent on the animal species. The chimeric antigens were generally more reactive than mixtures of three antigens. The most effective for the diagnosis of toxoplasmosis was SAG2-GRA1-ROP1L, which can detect specific anti-T. gondii antibodies in 100%, 93.8%, and 100% of positive serum samples from horses, pigs, and sheep, respectively. The present study shows that recombinant chimeric antigens can be successfully used to diagnose T. gondii infection in farm animals, and can replace the commonly used TLA. Copyright © 2015. Published by Elsevier Ireland Ltd.
New descriptors of homogeneity of the propagation of ventricular repolarization.
Batchvarov, V; Dilaveris, P; Färbom, P; Ghuran, A; Acar, B; Hnatkova, K; Camm, A J; Malik, M
2000-11-01
Available descriptors of irregularities of ventricular repolarization are of limited clinical value. We studied the effect of autonomic variations on several new descriptors of the three-dimensional T loop. Twelve-lead digital ECGs were recorded continuously in 40 healthy subjects at baseline in the supine position, during postural changes (supine-->sitting-->standing-->supine-->standing), and during Valsalva maneuver performed three times in the supine and three times in the standing positions. A minimum dimensional space was constructed from the 12-lead ECG, using singular value decomposition, on the basis of median ECG beats constructed from 10-second consecutive ECG recordings. Temporal variations (TLA and PL, which measure the T loop area, and LD, the interlead relationship during repolarization) and wavefront direction descriptors (TCRT, the deviation between the QRS and T vectors) were calculated and expressed as normalized values. Values of TLA, PL, and TCRT were significantly lower in the sitting than in the supine position (-38,139 +/- 9099 vs 47,133 +/- 7511, -0.017 +/- 0.005 vs 0.033 +/- 0.005 and -0.032 +/- 0.019 vs 0.071 +/- 0.015, respectively, P < 0.001 for all) and decreased further in the standing position (-88,288 +/- 14,468, -0.067 +/- 0.013, -0.198 +/- 0.025, respectively, P < 0.001 for all). LD increased from supine to sitting (98.7 +/- 29.4 vs -87.5 +/- 15.2, P < 0.001) and increased further, though nonsignificantly in the standing position (118.3 +/- 35.2). TLA, PL, and TCRT decreased from baseline during Valsalva in the supine (-34,118 +/- 11,424 vs 62,234 +/- 12,215, -0.038 +/- 0.014 vs 0.065 +/- 0.010, -0.08 +/- 0.03 vs 0.10 +/- 0.02, respectively, P < 0.001 for all) and standing positions (-108,263 +/- 21,051 vs -68,909 +/- 10,271, -0.109 +/- 0.014 vs -0.048 +/- 0.009, -0.30 +/- 0.035 vs -015 +/- 0.016, respectively, P < 0.05 for all). LD was significantly increased by Valsalva in the supine position (13 +/- 46 vs -153 +/- 30, P < 0.001) and nonsignificantly in the standing position (99 +/- 50 vs 86 +/- 30, P = NS). There were significant correlations among TLA, PL, and LD, and no significant correlation between TCRT and any of the temporal variation descriptors. These new temporal and wavefront direction descriptors are sensitive and rapid detectors of autonomic effects on ventricular repolarization.
Academic context and perceived mental workload of psychology students.
Rubio-Valdehita, Susana; López-Higes, Ramón; Díaz-Ramiro, Eva
2014-01-01
The excessive workload of university students is an academic stressor. Consequently, it is necessary to evaluate and control the workload in education. This research applies the NASA-TLX scale, as a measure of the workload. The objectives of this study were: (a) to measure the workload levels of a sample of 367 psychology students, (b) to group students according to their positive or negative perception of academic context (AC) and c) to analyze the effects of AC on workload. To assess the perceived AC, we used an ad hoc questionnaire designed according to Demand-Control-Social Support and Effort-Reward Imbalance models. Using cluster analysis, participants were classified into two groups (positive versus negative context). The differences between groups show that a positive AC improves performance (p < .01) and reduces feelings of overload (p < .02), temporal demand (p < .02), and nervousness and frustration (p < .001). Social relationships with peers and teachers, student autonomy and result satisfaction were relevant dimensions of the AC (p < .001 in all cases).
Heavy vehicle driver workload assessment. Task 3, task analysis data collection
DOT National Transportation Integrated Search
This technical report consists of a collection of task analytic data to support heavy vehicle driver workload assessment and protocol development. Data were collected from professional drivers to provide insights into the following issues: the meanin...
Estimating cognitive workload using wavelet entropy-based features during an arithmetic task.
Zarjam, Pega; Epps, Julien; Chen, Fang; Lovell, Nigel H
2013-12-01
Electroencephalography (EEG) has shown promise as an indicator of cognitive workload; however, precise workload estimation is an ongoing research challenge. In this investigation, seven levels of workload were induced using an arithmetic task, and the entropy of wavelet coefficients extracted from EEG signals is shown to distinguish all seven levels. For a subject-independent multi-channel classification scheme, the entropy features achieved high accuracy, up to 98% for channels from the frontal lobes, in the delta frequency band. This suggests that a smaller number of EEG channels in only one frequency band can be deployed for an effective EEG-based workload classification system. Together with analysis based on phase locking between channels, these results consistently suggest increased synchronization of neural responses for higher load levels. Copyright © 2013 Elsevier Ltd. All rights reserved.
Shuggi, Isabelle M; Oh, Hyuk; Shewokis, Patricia A; Gentili, Rodolphe J
2017-09-30
The assessment of mental workload can inform attentional resource allocation during task performance that is essential for understanding the underlying principles of human cognitive-motor behavior. While many studies have focused on mental workload in relation to human performance, a modest body of work has examined it in a motor practice/learning context without considering individual variability. Thus, this work aimed to examine mental workload by employing the NASA TLX as well as the changes in motor performance resulting from the practice of a novel reaching task. Two groups of participants practiced a reaching task at a high and low nominal difficulty during which a group-level analysis assessed the mental workload, motor performance and motor improvement dynamics. A secondary cluster analysis was also conducted to identify specific individual patterns of cognitive-motor responses. Overall, both group- and cluster-level analyses revealed that: (i) all participants improved their performance throughout motor practice, and (ii) an increase in mental workload was associated with a reduction of the quality of motor performance along with a slower rate of motor improvement. The results are discussed in the context of the optimal challenge point framework and in particular it is proposed that under the experimental conditions employed here, functional task difficulty: (i) would possibly depend on an individuals' information processing capabilities, and (ii) could be indexed by the level of mental workload which, when excessively heightened can decrease the quality of performance and more generally result in delayed motor improvements. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.
2015-01-01
Background The inclusion of new technologies in education has motivated the development of studies on mental workload. These technologies are now being used in the teaching and learning process. The analysis enables identification of factors intervening in this workload as well as planning of overload prevention for educational activities using these technologies. Objective To analyze the mental workload of an educational intervention with the Mobile Virtual Learning Object for the Assessment of Acute Pain in adults and newborns, according to the NASA Task Load Index criteria. Methods A methodological study with data collected from 5 nurses and 75 students, from November of 2013 to February of 2014. Results The highest students’ and specialists’ means were in the dimensions of “Mental demand” (57.20 ± 22.27; 51 ± 29.45) and “Performance” (58.47 ± 24.19; 73 ± 28.85). The specialists’ mental workload index was higher (50.20 ± 7.28) when compared with students’ (47.87 ± 16.85) on a scale from 0 to 100 (P=.557). Conclusions The instrument allowed for the assessment of mental workload after an online educational intervention with a mobile learning virtual object. An excessive overload was not identified among participants. Assessing mental workload from the use of educational technologies at the end of a task is a key to their applicability, with the aim of providing a more effective, stimulating, and long-lasting experience of the learning process. PMID:27731849
Scaling Deep Learning workloads: NVIDIA DGX-1/Pascal and Intel Knights Landing
Gawande, Nitin A.; Daily, Jeff A.; Siegel, Charles; ...
2018-05-05
Deep Learning (DL) algorithms have become ubiquitous in data analytics. As a result, major computing vendors—including NVIDIA, Intel, AMD, and IBM—have architectural road maps influenced by DL workloads. Furthermore, several vendors have recently advertised new computing products as accelerating large DL workloads. Unfortunately, it is difficult for data scientists to quantify the potential of these different products. Here, this article provides a performance and power analysis of important DL workloads on two major parallel architectures: NVIDIA DGX-1 (eight Pascal P100 GPUs interconnected with NVLink) and Intel Knights Landing (KNL) CPUs interconnected with Intel Omni-Path or Cray Aries. Our evaluation consistsmore » of a cross section of convolutional neural net workloads: CifarNet, AlexNet, GoogLeNet, and ResNet50 topologies using the Cifar10 and ImageNet datasets. The workloads are vendor-optimized for each architecture. We use sequentially equivalent implementations to maintain iso-accuracy between parallel and sequential DL models. Our analysis indicates that although GPUs provide the highest overall performance, the gap can close for some convolutional networks; and the KNL can be competitive in performance/watt. We find that NVLink facilitates scaling efficiency on GPUs. However, its importance is heavily dependent on neural network architecture. Furthermore, for weak-scaling—sometimes encouraged by restricted GPU memory—NVLink is less important.« less
Scaling Deep Learning workloads: NVIDIA DGX-1/Pascal and Intel Knights Landing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gawande, Nitin A.; Daily, Jeff A.; Siegel, Charles
Deep Learning (DL) algorithms have become ubiquitous in data analytics. As a result, major computing vendors—including NVIDIA, Intel, AMD, and IBM—have architectural road maps influenced by DL workloads. Furthermore, several vendors have recently advertised new computing products as accelerating large DL workloads. Unfortunately, it is difficult for data scientists to quantify the potential of these different products. Here, this article provides a performance and power analysis of important DL workloads on two major parallel architectures: NVIDIA DGX-1 (eight Pascal P100 GPUs interconnected with NVLink) and Intel Knights Landing (KNL) CPUs interconnected with Intel Omni-Path or Cray Aries. Our evaluation consistsmore » of a cross section of convolutional neural net workloads: CifarNet, AlexNet, GoogLeNet, and ResNet50 topologies using the Cifar10 and ImageNet datasets. The workloads are vendor-optimized for each architecture. We use sequentially equivalent implementations to maintain iso-accuracy between parallel and sequential DL models. Our analysis indicates that although GPUs provide the highest overall performance, the gap can close for some convolutional networks; and the KNL can be competitive in performance/watt. We find that NVLink facilitates scaling efficiency on GPUs. However, its importance is heavily dependent on neural network architecture. Furthermore, for weak-scaling—sometimes encouraged by restricted GPU memory—NVLink is less important.« less
Domestic chores workload and depressive symptoms among children affected by HIV/AIDS in China.
Yu, Yun; Li, Xiaoming; Zhang, Liying; Zhao, Junfeng; Zhao, Guoxiang; Zheng, Yu; Stanton, Bonita
2013-01-01
Limited data are available regarding the effects of domestic chores workload on psychological problems among children affected by HIV/AIDS in China. The current study aims to examine association between children's depressive symptoms and the domestic chores workload (i.e., the frequency and the amount of time doing domestic chores). Data were derived from the baseline survey of a longitudinal study which investigated the impact of parental HIV/AIDS on psychological problems of children. A total of 1449 children in family-based care were included in the analysis: 579 orphaned children who lost one or both parents due to AIDS, 466 vulnerable children living with one or both parents being infected with HIV, and 404 comparison children who did not have HIV/AIDS-infected family members in their families. Results showed differences on domestic chores workload between children affected by HIV/AIDS (orphans and vulnerable children) and the comparison children. Children affected by HIV/AIDS worked more frequently and worked longer time on domestic chores than the comparison children. Multivariate linear regression analysis showed that domestic chores workload was positively associated with depressive symptoms. The data suggest that children affected by HIV/AIDS may face increasing burden of domestic chores and it is necessary to reduce the excessive workload of domestic chores among children affected by HIV/AIDS through increasing community-based social support for children in the families affected by HIV/AIDS.
Mental workload during n-back task-quantified in the prefrontal cortex using fNIRS.
Herff, Christian; Heger, Dominic; Fortmann, Ole; Hennrich, Johannes; Putze, Felix; Schultz, Tanja
2013-01-01
When interacting with technical systems, users experience mental workload. Particularly in multitasking scenarios (e.g., interacting with the car navigation system while driving) it is desired to not distract the users from their primary task. For such purposes, human-machine interfaces (HCIs) are desirable which continuously monitor the users' workload and dynamically adapt the behavior of the interface to the measured workload. While memory tasks have been shown to elicit hemodynamic responses in the brain when averaging over multiple trials, a robust single trial classification is a crucial prerequisite for the purpose of dynamically adapting HCIs to the workload of its user. The prefrontal cortex (PFC) plays an important role in the processing of memory and the associated workload. In this study of 10 subjects, we used functional Near-Infrared Spectroscopy (fNIRS), a non-invasive imaging modality, to sample workload activity in the PFC. The results show up to 78% accuracy for single-trial discrimination of three levels of workload from each other. We use an n-back task (n ∈ {1, 2, 3}) to induce different levels of workload, forcing subjects to continuously remember the last one, two, or three of rapidly changing items. Our experimental results show that measuring hemodynamic responses in the PFC with fNIRS, can be used to robustly quantify and classify mental workload. Single trial analysis is still a young field that suffers from a general lack of standards. To increase comparability of fNIRS methods and results, the data corpus for this study is made available online.
Mental workload during n-back task—quantified in the prefrontal cortex using fNIRS
Herff, Christian; Heger, Dominic; Fortmann, Ole; Hennrich, Johannes; Putze, Felix; Schultz, Tanja
2014-01-01
When interacting with technical systems, users experience mental workload. Particularly in multitasking scenarios (e.g., interacting with the car navigation system while driving) it is desired to not distract the users from their primary task. For such purposes, human-machine interfaces (HCIs) are desirable which continuously monitor the users' workload and dynamically adapt the behavior of the interface to the measured workload. While memory tasks have been shown to elicit hemodynamic responses in the brain when averaging over multiple trials, a robust single trial classification is a crucial prerequisite for the purpose of dynamically adapting HCIs to the workload of its user. The prefrontal cortex (PFC) plays an important role in the processing of memory and the associated workload. In this study of 10 subjects, we used functional Near-Infrared Spectroscopy (fNIRS), a non-invasive imaging modality, to sample workload activity in the PFC. The results show up to 78% accuracy for single-trial discrimination of three levels of workload from each other. We use an n-back task (n ∈ {1, 2, 3}) to induce different levels of workload, forcing subjects to continuously remember the last one, two, or three of rapidly changing items. Our experimental results show that measuring hemodynamic responses in the PFC with fNIRS, can be used to robustly quantify and classify mental workload. Single trial analysis is still a young field that suffers from a general lack of standards. To increase comparability of fNIRS methods and results, the data corpus for this study is made available online. PMID:24474913
Heavy vehicle driver workload assessment. Task 1, task analysis data and protocols review
DOT National Transportation Integrated Search
This report contains a review of available task analytic data and protocols pertinent to heavy vehicle operation and determination of the availability and relevance of such data to heavy vehicle driver workload assessment. Additionally, a preliminary...
A comprehensive prediction and evaluation method of pilot workload
Feng, Chuanyan; Wanyan, Xiaoru; Yang, Kun; Zhuang, Damin; Wu, Xu
2018-01-01
BACKGROUND: The prediction and evaluation of pilot workload is a key problem in human factor airworthiness of cockpit. OBJECTIVE: A pilot traffic pattern task was designed in a flight simulation environment in order to carry out the pilot workload prediction and improve the evaluation method. METHODS: The prediction of typical flight subtasks and dynamic workloads (cruise, approach, and landing) were built up based on multiple resource theory, and a favorable validity was achieved by the correlation analysis verification between sensitive physiological data and the predicted value. RESULTS: Statistical analysis indicated that eye movement indices (fixation frequency, mean fixation time, saccade frequency, mean saccade time, and mean pupil diameter), Electrocardiogram indices (mean normal-to-normal interval and the ratio between low frequency and sum of low frequency and high frequency), and Electrodermal Activity indices (mean tonic and mean phasic) were all sensitive to typical workloads of subjects. CONCLUSION: A multinominal logistic regression model based on combination of physiological indices (fixation frequency, mean normal-to-normal interval, the ratio between low frequency and sum of low frequency and high frequency, and mean tonic) was constructed, and the discriminate accuracy was comparatively ideal with a rate of 84.85%. PMID:29710742
A comprehensive prediction and evaluation method of pilot workload.
Feng, Chuanyan; Wanyan, Xiaoru; Yang, Kun; Zhuang, Damin; Wu, Xu
2018-01-01
The prediction and evaluation of pilot workload is a key problem in human factor airworthiness of cockpit. A pilot traffic pattern task was designed in a flight simulation environment in order to carry out the pilot workload prediction and improve the evaluation method. The prediction of typical flight subtasks and dynamic workloads (cruise, approach, and landing) were built up based on multiple resource theory, and a favorable validity was achieved by the correlation analysis verification between sensitive physiological data and the predicted value. Statistical analysis indicated that eye movement indices (fixation frequency, mean fixation time, saccade frequency, mean saccade time, and mean pupil diameter), Electrocardiogram indices (mean normal-to-normal interval and the ratio between low frequency and sum of low frequency and high frequency), and Electrodermal Activity indices (mean tonic and mean phasic) were all sensitive to typical workloads of subjects. A multinominal logistic regression model based on combination of physiological indices (fixation frequency, mean normal-to-normal interval, the ratio between low frequency and sum of low frequency and high frequency, and mean tonic) was constructed, and the discriminate accuracy was comparatively ideal with a rate of 84.85%.
Zero-field random-field effect in diluted triangular lattice antiferromagnet CuFe1-xAlxO2
NASA Astrophysics Data System (ADS)
Nakajima, T.; Mitsuda, S.; Kitagawa, K.; Terada, N.; Komiya, T.; Noda, Y.
2007-04-01
We performed neutron scattering experiments on a diluted triangular lattice antiferromagnet (TLA), CuFe1-xAlxO2 with x = 0.10. The detailed analysis of the scattering profiles revealed that the scattering function of magnetic reflection is described as the sum of a Lorentzian term and a Lorentzian-squared term with anisotropic width. The Lorentzian-squared term dominating at low temperature is indicative of the domain state in the prototypical random-field Ising model. Taking account of the sinusoidally amplitude-modulated magnetic structure with incommensurate wavenumber in CuFe1-xAlxO2 with x = 0.10, we conclude that the effective random field arises even at zero field, owing to the combination of site-random magnetic vacancies and the sinusoidal structure that is regarded as a partially disordered (PD) structure in a wide sense, as reported in the typical three-sublattice PD phase of a diluted Ising TLA, CsCo0.83Mg0.17Br3 (van Duijn et al 2004 Phys. Rev. Lett. 92 077202). While the previous study revealed the existence of a domain state in CsCo0.83Mg0.17Br3 by detecting magnetic reflections specific to the spin configuration near the domain walls, our present study revealed the existence of a domain state in CuFe1-xAlxO2 (x = 0.10) by determination of the functional form of the scattering function.
Tubbs-Cooley, Heather L; Mara, Constance A; Carle, Adam C; Gurses, Ayse P
2018-02-12
The NASA Task Load Index (NASA-TLX) is a subjective workload assessment scale developed for use in aviation and increasingly applied to healthcare. The scale purports to measure overall workload as a single variable calculated by summing responses to six items. Since no data address the validity of this scoring approach in health care, we evaluated the single factor structure of the NASA-TLX as a measure of overall workload among intenisive care nurses. Confirmatory factor analysis of data from two studies of nurse workload in neonatal, paediatric, and adult intensive care units. Study 1 data were obtained from 136 nurses in one neonatal intensive care unit. Study 2 data were collected from 300 nurses in 17 adult, paediatric and neonatal units. Nurses rated their workload using the NASA-TLX's paper version. A single factor model testing whether all six items measured a single overall workload variable fit least well (RMSEA = 0.14; CFI = 0.91; TLI = 0.85). A second model that specified two items as outcomes of overall workload had acceptable fit (RMSEA = 0.08; CFI = 0.97; TLI = 0.95) while a third model of four items fit best (RMSEA = 0.06; CFI > 0.99; TLI = 0.99). A summed score from four of six NASA-TLX items appears to most reliably measure a single overall workload variable among intensive care nurses. Copyright © 2018 Elsevier Ltd. All rights reserved.
The psychometrics of mental workload: multiple measures are sensitive but divergent.
Matthews, Gerald; Reinerman-Jones, Lauren E; Barber, Daniel J; Abich, Julian
2015-02-01
A study was run to test the sensitivity of multiple workload indices to the differing cognitive demands of four military monitoring task scenarios and to investigate relationships between indices. Various psychophysiological indices of mental workload exhibit sensitivity to task factors. However, the psychometric properties of multiple indices, including the extent to which they intercorrelate, have not been adequately investigated. One hundred fifty participants performed in four task scenarios based on a simulation of unmanned ground vehicle operation. Scenarios required threat detection and/or change detection. Both single- and dual-task scenarios were used. Workload metrics for each scenario were derived from the electroencephalogram (EEG), electrocardiogram, transcranial Doppler sonography, functional near infrared, and eye tracking. Subjective workload was also assessed. Several metrics showed sensitivity to the differing demands of the four scenarios. Eye fixation duration and the Task Load Index metric derived from EEG were diagnostic of single-versus dual-task performance. Several other metrics differentiated the two single tasks but were less effective in differentiating single- from dual-task performance. Psychometric analyses confirmed the reliability of individual metrics but failed to identify any general workload factor. An analysis of difference scores between low- and high-workload conditions suggested an effort factor defined by heart rate variability and frontal cortex oxygenation. General workload is not well defined psychometrically, although various individual metrics may satisfy conventional criteria for workload assessment. Practitioners should exercise caution in using multiple metrics that may not correspond well, especially at the level of the individual operator.
Hu, Jiangbi; Wang, Ronghua
2018-02-17
Guaranteeing a safe and comfortable driving workload can contribute to reducing traffic injuries. In order to provide safe and comfortable threshold values, this study attempted to classify driving workload from the aspects of human factors mainly affected by highway geometric conditions and to determine the thresholds of different workload classifications. This article stated a hypothesis that the values of driver workload change within a certain range. Driving workload scales were stated based on a comprehensive literature review. Through comparative analysis of different psychophysiological measures, heart rate variability (HRV) was chosen as the representative measure for quantifying driving workload by field experiments. Seventy-two participants (36 car drivers and 36 large truck drivers) and 6 highways with different geometric designs were selected to conduct field experiments. A wearable wireless dynamic multiparameter physiological detector (KF-2) was employed to detect physiological data that were simultaneously correlated to the speed changes recorded by a Global Positioning System (GPS) (testing time, driving speeds, running track, and distance). Through performing statistical analyses, including the distribution of HRV during the flat, straight segments and P-P plots of modified HRV, a driving workload calculation model was proposed. Integrating driving workload scales with values, the threshold of each scale of driving workload was determined by classification and regression tree (CART) algorithms. The driving workload calculation model was suitable for driving speeds in the range of 40 to 120 km/h. The experimental data of 72 participants revealed that driving workload had a significant effect on modified HRV, revealing a change in driving speed. When the driving speed was between 100 and 120 km/h, drivers showed an apparent increase in the corresponding modified HRV. The threshold value of the normal driving workload K was between -0.0011 and 0.056 for a car driver and between -0.00086 and 0.067 for a truck driver. Heart rate variability was a direct and effective index for measuring driving workload despite being affected by multiple highway alignment elements. The driving workload model and the thresholds of driving workload classifications can be used to evaluate the quality of highway geometric design. A higher quality of highway geometric design could keep driving workload within a safer and more comfortable range. This study provided insight into reducing traffic injuries from the perspective of disciplinary integration of highway engineering and human factor engineering.
Development of the CarMen-Q Questionnaire for mental workload assessment.
Rubio-Valdehita, Susana; López-Núñez, María I; López-Higes, Ramón; Díaz-Ramiro, Eva M
2017-11-01
Mental workload has emerged as one of the most important occupational risk factors present in most psychological and physical diseases caused by work. In view of the lack of specific tools to assess mental workload, the objective of this research was to assess the construct validity and reliability of a new questionnaire for mental workload assessment (CarMen-Q). The sample was composed of 884 workers from several professional sectors, between 18 and 65 years old, 53.4% men and 46.6% women. To evaluate the validity based on relationships with other measures, the NASA-TLX scale was also administered. Confirmatory factor analysis showed an internal structure made up of four dimensions: cognitive, temporal and emotional demands and performance requirement. The results show satisfactory evidence of validity based on relationships with NASA-TLX and good reliability. The questionnaire has good psychometric properties and can be an easy, brief, useful tool for mental workload diagnosis and prevention.
Predictors of nursing workload in elderly patients admitted to intensive care units.
Sousa, Cleber Ricardo de; Gonçalves, Leilane Andrade; Toffoleto, Maria Cecília; Leão, Karine; Padilha, Kátia Grillo
2008-01-01
The age of patients is a controversial issue in admission to intensive care unit (ICU). The aim of this study was to compare severity and nursing workload of elderly patients with 60-69, 70-79, and e"80 years of age and to identify predictors of nursing workload in elderly patients. A cross sectional study was performed with a sample of 71 elderly patients admitted to three ICU in the city of Sao Paulo, Brazil from October to November 2004. Data were prospectively collected using Nursing Activities Score (NAS) and Simplified Acute Physiology Score II (SAPS II). There was no significant difference in nursing workload among the elderly patients age subgroups (p=0.84). Multiple regression analysis indicated that the independent risk factors of high nursing workload were severity, age e"70 years, and to be a surgical ICU patient. Age as an isolated factor should not be discriminative for elderly patients admission to ICU.
Eye Tracking Metrics for Workload Estimation in Flight Deck Operation
NASA Technical Reports Server (NTRS)
Ellis, Kyle; Schnell, Thomas
2010-01-01
Flight decks of the future are being enhanced through improved avionics that adapt to both aircraft and operator state. Eye tracking allows for non-invasive analysis of pilot eye movements, from which a set of metrics can be derived to effectively and reliably characterize workload. This research identifies eye tracking metrics that correlate to aircraft automation conditions, and identifies the correlation of pilot workload to the same automation conditions. Saccade length was used as an indirect index of pilot workload: Pilots in the fully automated condition were observed to have on average, larger saccadic movements in contrast to the guidance and manual flight conditions. The data set itself also provides a general model of human eye movement behavior and so ostensibly visual attention distribution in the cockpit for approach to land tasks with various levels of automation, by means of the same metrics used for workload algorithm development.
Barbosa, Joselina; Silva, Álvaro; Ferreira, Maria Amélia; Severo, Milton
2018-04-16
One of the most important factors that makes the transition from secondary school to medical school challenging is the inability to put in the study time that a medical school curriculum demands. The implementation of regulated learning is essential for students to cope with medical course environment and succeed. This study aimed to investigate the reciprocal relationships between self-regulated learning skills (SRLS) and academic workload (AW) across secondary school to medical school transition. Freshmen enrolled in medical school (N = 102) completed questionnaires at the beginning and at the end of their academic year, assessing AW (measured as study time hours and perceived workload), SRLS (planning and strategies for learning assessment, motivation and action to learning and self-directedness) and academic achievement. An exploratory factor analysis (EFA) and a longitudinal path analysis were performed. According to the EFA, study time and perceived workload revealed two factors of AW: students who had a high perceived workload also demonstrated increased study time (tandem AW); and those who had a low perceived workload also demonstrated increased study time (inverse AW). Only a longitudinal relationship between SRLS and AW was found in the path analysis: prior self-directedness was related to later tandem AW. Moreover, success during the first year of medical school is dependent on exposure to motivation, self-directedness and high study time without overload during secondary school and medical school, and prior academic achievement. By better understanding these relationships, teachers can create conditions that support academic success during the first year medical school.
Unsupervised classification of operator workload from brain signals.
Schultze-Kraft, Matthias; Dähne, Sven; Gugler, Manfred; Curio, Gabriel; Blankertz, Benjamin
2016-06-01
In this study we aimed for the classification of operator workload as it is expected in many real-life workplace environments. We explored brain-signal based workload predictors that differ with respect to the level of label information required for training, including entirely unsupervised approaches. Subjects executed a task on a touch screen that required continuous effort of visual and motor processing with alternating difficulty. We first employed classical approaches for workload state classification that operate on the sensor space of EEG and compared those to the performance of three state-of-the-art spatial filtering methods: common spatial patterns (CSPs) analysis, which requires binary label information; source power co-modulation (SPoC) analysis, which uses the subjects' error rate as a target function; and canonical SPoC (cSPoC) analysis, which solely makes use of cross-frequency power correlations induced by different states of workload and thus represents an unsupervised approach. Finally, we investigated the effects of fusing brain signals and peripheral physiological measures (PPMs) and examined the added value for improving classification performance. Mean classification accuracies of 94%, 92% and 82% were achieved with CSP, SPoC, cSPoC, respectively. These methods outperformed the approaches that did not use spatial filtering and they extracted physiologically plausible components. The performance of the unsupervised cSPoC is significantly increased by augmenting it with PPM features. Our analyses ensured that the signal sources used for classification were of cortical origin and not contaminated with artifacts. Our findings show that workload states can be successfully differentiated from brain signals, even when less and less information from the experimental paradigm is used, thus paving the way for real-world applications in which label information may be noisy or entirely unavailable.
Mazur, Lukasz M; Mosaly, Prithima R; Moore, Carlton; Comitz, Elizabeth; Yu, Fei; Falchook, Aaron D; Eblan, Michael J; Hoyle, Lesley M; Tracton, Gregg; Chera, Bhishamjit S; Marks, Lawrence B
2016-11-01
To assess the relationship between (1) task demands and workload, (2) task demands and performance, and (3) workload and performance, all during physician-computer interactions in a simulated environment. Two experiments were performed in 2 different electronic medical record (EMR) environments: WebCIS (n = 12) and Epic (n = 17). Each participant was instructed to complete a set of prespecified tasks on 3 routine clinical EMR-based scenarios: urinary tract infection (UTI), pneumonia (PN), and heart failure (HF). Task demands were quantified using behavioral responses (click and time analysis). At the end of each scenario, subjective workload was measured using the NASA-Task-Load Index (NASA-TLX). Physiological workload was measured using pupillary dilation and electroencephalography (EEG) data collected throughout the scenarios. Performance was quantified based on the maximum severity of omission errors. Data analysis indicated that the PN and HF scenarios were significantly more demanding than the UTI scenario for participants using WebCIS (P < .01), and that the PN scenario was significantly more demanding than the UTI and HF scenarios for participants using Epic (P < .01). In both experiments, the regression analysis indicated a significant relationship only between task demands and performance (P < .01). Results suggest that task demands as experienced by participants are related to participants' performance. Future work may support the notion that task demands could be used as a quality metric that is likely representative of performance, and perhaps patient outcomes. The present study is a reasonable next step in a systematic assessment of how task demands and workload are related to performance in EMR-evolving environments. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Unsupervised classification of operator workload from brain signals
NASA Astrophysics Data System (ADS)
Schultze-Kraft, Matthias; Dähne, Sven; Gugler, Manfred; Curio, Gabriel; Blankertz, Benjamin
2016-06-01
Objective. In this study we aimed for the classification of operator workload as it is expected in many real-life workplace environments. We explored brain-signal based workload predictors that differ with respect to the level of label information required for training, including entirely unsupervised approaches. Approach. Subjects executed a task on a touch screen that required continuous effort of visual and motor processing with alternating difficulty. We first employed classical approaches for workload state classification that operate on the sensor space of EEG and compared those to the performance of three state-of-the-art spatial filtering methods: common spatial patterns (CSPs) analysis, which requires binary label information; source power co-modulation (SPoC) analysis, which uses the subjects’ error rate as a target function; and canonical SPoC (cSPoC) analysis, which solely makes use of cross-frequency power correlations induced by different states of workload and thus represents an unsupervised approach. Finally, we investigated the effects of fusing brain signals and peripheral physiological measures (PPMs) and examined the added value for improving classification performance. Main results. Mean classification accuracies of 94%, 92% and 82% were achieved with CSP, SPoC, cSPoC, respectively. These methods outperformed the approaches that did not use spatial filtering and they extracted physiologically plausible components. The performance of the unsupervised cSPoC is significantly increased by augmenting it with PPM features. Significance. Our analyses ensured that the signal sources used for classification were of cortical origin and not contaminated with artifacts. Our findings show that workload states can be successfully differentiated from brain signals, even when less and less information from the experimental paradigm is used, thus paving the way for real-world applications in which label information may be noisy or entirely unavailable.
The Relationship between Social Capital in Hospitals and Physician Job Satisfaction
Ommen, Oliver; Driller, Elke; Köhler, Thorsten; Kowalski, Christoph; Ernstmann, Nicole; Neumann, Melanie; Steffen, Petra; Pfaff, Holger
2009-01-01
Background Job satisfaction in the hospital is an important predictor for many significant management ratios. Acceptance in professional life or high workload are known as important predictors for job satisfaction. The influence of social capital in hospitals on job satisfaction within the health care system, however, remains to be determined. Thus, this article aimed at analysing the relationship between overall job satisfaction of physicians and social capital in hospitals. Methods The results of this study are based upon questionnaires sent by mail to 454 physicians working in the field of patient care in 4 different German hospitals in 2002. 277 clinicians responded to the poll, for a response rate of 61%. Analysis was performed using three linear regression models with physician overall job satisfaction as the dependent variable and age, gender, professional experience, workload, and social capital as independent variables. Results The first regression model explained nearly 9% of the variance of job satisfaction. Whereas job satisfaction increased slightly with age, gender and professional experience were not identified as significant factors to explain the variance. Setting up a second model with the addition of subjectively-perceived workload to the analysis, the explained variance increased to 18% and job satisfaction decreased significantly with increasing workload. The third model including social capital in hospital explained 36% of the variance with social capital, professional experience and workload as significant factors. Conclusion This analysis demonstrated that the social capital of an organisation, in addition to professional experience and workload, represents a significant predictor of overall job satisfaction of physicians working in the field of patient care. Trust, mutual understanding, shared aims, and ethical values are qualities of social capital that unify members of social networks and communities and enable them to act cooperatively. PMID:19445692
Temporal Learning Analytics for Adaptive Assessment
ERIC Educational Resources Information Center
Papamitsiou, Zacharoula; Economides, Anastasios A.
2014-01-01
Accurate and early predictions of student performance could significantly affect interventions during teaching and assessment, which gradually could lead to improved learning outcomes. In our research, we seek to identify and formalize temporal parameters as predictors of performance ("temporal learning analytics" or TLA) and examine…
NASA Astrophysics Data System (ADS)
Chowdhury, D. P.; Chaudhuri, Jayanta; Raju, V. S.; Das, S. K.; Bhattacharjee, B. B.; Gangadharan, S.
1989-07-01
The wear analysis of a compression ring and cylinder housing of an Internal Combustion Engine by thin layer activation (TLA) with 40 MeV α-particles from the Variable Energy Cyclotron at Calcutta is reported. The calibration curves have been obtained for Fe and Ni using stacked foil activation technique for determining the absolute wear in these machine parts. It has been possible to determine the pattern of wear on the points along the surface of machine components. The minimum detectable depth in this wear study has been estimated at 0.11 ± 0.04 μm.
Holec-Gąsior, Lucyna; Ferra, Bartłomiej; Drapała, Dorota; Lautenbach, Dariusz
2012-01-01
This study presents an evaluation of the MIC1 (microneme protein 1)-MAG1 (matrix antigen 1) Toxoplasma gondii recombinant chimeric antigen for the serodiagnosis of human toxoplasmosis for the first time. The recombinant MIC1-MAG1 antigen was obtained as a fusion protein containing His tags at the N- and C-terminal ends using an Escherichia coli expression system. After purification by metal affinity chromatography, the chimeric protein was tested for usefulness in an enzyme-linked immunosorbent assay (ELISA) for the detection of anti-T. gondii immunoglobulin G (IgG). One hundred ten sera from patients at different stages of infection and 40 sera from seronegative patients were examined. The results obtained for the MIC1-MAG1 chimeric antigen were compared with those of IgG ELISAs using a Toxoplasma lysate antigen (TLA), a combination of recombinant antigens (rMIC1ex2-rMAG1) and single recombinant proteins (rMIC1ex2 and rMAG1). The sensitivity of the IgG ELISA calculated from all of the positive serum samples was similar for the MIC1-MAG1 chimeric antigen (90.8%) and the TLA (91.8%), whereas the sensitivities of the other antigenic samples used were definitely lower, at 69.1% for the mixture of antigens, 75.5% for the rMIC1ex2, and 60% for rMAG1. This study demonstrates that the MIC1-MAG1 recombinant chimeric antigen can be used instead of the TLA in the serodiagnosis of human toxoplasmosis. PMID:22116686
Cadmium removal from water using thiolactic acid-modified titanium dioxide nanoparticles.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Skubal, L. R.; Meshkov, N. K.; Rajh, T.
2002-05-31
This study investigated the use of titanium dioxide (TiO{sub 2}) nanoparticles to remove aqueous cadmium from simulated wastewaters. Nanosized (45 A) colloids of anatase TiO{sub 2} were synthesized through the controlled hydrolysis of TiCl4 and their surfaces modified with the bidental chelating agent thiolactic acid (TLA). Colloids were introduced into 65 ppm cadmium-laden waters, and the suspensions were purged aerobically, anoxically with an inert gas, or by a sequential aerobic/anoxic purge. Suspensions were illuminated with 253.7 nm light. In each experiment, samples were taken from the reactor, filtered, and the filtrates analyzed by atomic absorption spectroscopy for residual cadmium. Resultsmore » from the aerobic experiments exhibited minimal (approximately 10%) removal of the cadmium from solution and no reduction of the metal on either the modified or the unmodified colloid. Anoxic results were more promising, showing no cadmium reduction on the unmodified colloid but a 40% adsorption and reduction (from a +2 valence state to elemental cadmium as determined by methyl viologen tests) of cadmium on TLA-modified colloid in the presence of light. Results from the mixed atmospheric conditions fared the best and demonstrated that in the absence of light, approximately 20% of aqueous cadmium was sorbed to the modified colloid via a Freundlich adsorption isotherm. Upon illumination, greater than 90% of cadmium was removed by both adsorption and reduction processes onto the TLA-modified TiO{sub 2}. These removal and reduction processes were catalytic in nature. Results from this study are significant because to date, no other research in the literature has been able to accomplish cadmium removal and reduction using TiO{sub 2}.« less
Le Garlantezec, C; Vidal, V Franco; Guerin, J; Bébéar, J P; Liguoro, D; Darrouzet, V
2005-01-01
To review and study the management of CPA meningiomas through the experience of an otoneurosurgical team. Fourty-two patients (44 meningiomas) were considered. Seventy-seven per cent of tumors (34 cases) were operated on; 6 tumors (14.6%) were exclusively irradiated using fractionated radiation therapy (FRT) and four only surveyed (9,8%). transpetrosal approaches were exclusively used. These were translabyrinthine (TLA) in 47%, widened retrolabyrinthine (WRLA) in 41% of cases, transcochlear approach (TCA) in three cases and a middle fossa in one. A transtentorial approach was combined in 35% of cases (8 TLA, 4 WRLA). Surgical removal was incomplete in 11,8% of cases; in 3 cases growing tumor was treated by FRT included one case of anaplasic tumor Postoperative complications were: 1 meningitis, 1 wound abscess, 2 hydrocephalus (6%) and 4 CSF fistulas (12%). No complications have been observed during the last 7 years (21 cases). House and Brackmann Grade 1 or 2 facial function was obtained in 59% of cases (but 10 patients had a preoperative facial nerve paresis). A normal or subnormal AAO-HNS Class A-B Hearing could be preserved in 57% of WRLA. Radiation therapy allowed tumor shrinkage in all cases. In 3 cases this regression was of more than 50%. Surgery is the gold standard in treating CPA meningiomas. Transpetrosal approaches and particularly WRLA pure or combined to a transtentorial approach are for us the best way to remove these tumors in preserving hearing and facial nerve function. When hearing is poor or when tumor extension to the clivus or the premeatal area is consistent a TLA is either planned preoperatively or obtained from a WRLA.
Brexanolone as adjunctive therapy in super‐refractory status epilepticus
Claassen, Jan; Wainwright, Mark S.; Husain, Aatif M.; Vaitkevicius, Henrikas; Raines, Shane; Hoffmann, Ethan; Colquhoun, Helen; Doherty, James J.; Kanes, Stephen J.
2017-01-01
Objective Super‐refractory status epilepticus (SRSE) is a life‐threatening form of status epilepticus that continues or recurs despite 24 hours or more of anesthetic treatment. We conducted a multicenter, phase 1/2 study in SRSE patients to evaluate the safety and tolerability of brexanolone (USAN; formerly SAGE‐547 Injection), a proprietary, aqueous formulation of the neuroactive steroid, allopregnanolone. Secondary objectives included pharmacokinetic assessment and open‐label evaluation of brexanolone response during and after anesthetic third‐line agent (TLA) weaning. Methods Patients receiving TLAs for SRSE control were eligible for open‐label, 1‐hour brexanolone loading infusions, followed by maintenance infusion. After 48 hours of brexanolone infusion, TLAs were weaned during brexanolone maintenance. After 4 days, the brexanolone dose was tapered. Safety and functional status were assessed over 3 weeks of follow‐up. Results Twenty‐five patients received open‐label study drug. No serious adverse events (SAEs) were attributable to study drug, as determined by the Safety Review Committee. Sixteen patients (64%) experienced ≥1 SAE. Six patient deaths occurred, all deemed related to underlying medical conditions. Twenty‐two patients underwent ≥1 TLA wean attempt. Seventeen (77%) met the response endpoint of weaning successfully off TLAs before tapering brexanolone. Sixteen (73%) were successfully weaned off TLAs within 5 days of initiating brexanolone infusion without anesthetic agent reinstatement in the following 24 hours. Interpretation In an open‐label cohort of limited size, brexanolone demonstrated tolerability among SRSE patients of heterogeneous etiologies and was associated with a high rate of successful TLA weaning. The results suggest the possible development of brexanolone as an adjunctive therapy for SRSE requiring pharmacological coma for seizure control. Ann Neurol 2017;82:342–352 PMID:28779545
Data-linked pilot reply time on controller workload and communication in a simulated terminal option
DOT National Transportation Integrated Search
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...
Improved lower extremity pedaling mechanics in individuals with stroke under maximal workloads.
Linder, Susan M; Rosenfeldt, Anson B; Bazyk, Andrew S; Koop, Mandy Miller; Ozinga, Sarah; Alberts, Jay L
2018-05-01
Background Individuals with stroke present with motor control deficits resulting in the abnormal activation and timing of agonist and antagonist muscles and inefficient movement patterns. The analysis of pedaling biomechanics provides a window into understanding motor control deficits, which vary as a function of workload. Understanding the relationship between workload and motor control is critical when considering exercise prescription during stroke rehabilitation. Objectives To characterize pedaling kinematics and motor control processes under conditions in which workload was systematically increased to an eventual patient-specific maximum. Methods A cohort study was conducted in which 18 individuals with chronic stroke underwent a maximal exertion cardiopulmonary exercise test on a stationary cycle ergometer, during which pedaling torque was continuously recorded. Measures of force production, pedaling symmetry, and pedaling smoothness were obtained. Results Mean Torque increased significantly (p < 0.05) for both legs from initial to terminal workloads. Mean torque Symmetry Index, calculated for down and upstroke portions of the pedaling action, improved from 0.37(0.29) to 0.29(0.35) during downstroke (p = 0.007), and worsened during the upstroke: -0.37(0.38) to -0.62(0.46) (p < 0.001) from initial to terminal workloads. Low Torque Duration improved from initial to terminal workloads, decreasing from 121.1(52.9) to 58.1(39.6) degrees (p < 0.001), respectively. Smoothness of pedaling improved significantly from initial to terminal workloads (p < 0.001). Conclusions Improved pedaling kinematics at terminal workloads indicate that individuals with stroke demonstrate improved motor control with respect to the timing, sequencing, and activation of hemiparetic lower extremity musculature compared to lower workloads. Therapeutic prescription involving higher resistance may be necessary to sufficiently engage and activate the paretic lower extremity.
Fault and Error Latency Under Real Workload: an Experimental Study. Ph.D. Thesis
NASA Technical Reports Server (NTRS)
Chillarege, Ram
1986-01-01
A practical methodology for the study of fault and error latency is demonstrated under a real workload. This is the first study that measures and quantifies the latency under real workload and fills a major gap in the current understanding of workload-failure relationships. The methodology is based on low level data gathered on a VAX 11/780 during the normal workload conditions of the installation. Fault occurrence is simulated on the data, and the error generation and discovery process is reconstructed to determine latency. The analysis proceeds to combine the low level activity data with high level machine performance data to yield a better understanding of the phenomena. A strong relationship exists between latency and workload and that relationship is quantified. The sampling and reconstruction techniques used are also validated. Error latency in the memory where the operating system resides was studied using data on the physical memory access. Fault latency in the paged section of memory was determined using data from physical memory scans. Error latency in the microcontrol store was studied using data on the microcode access and usage.
Designing workload analysis questionnaire to evaluate needs of employees
NASA Astrophysics Data System (ADS)
Astuti, Rahmaniyah Dwi; Navi, Muhammad Abdu Haq
2018-02-01
Incompatibility between workload with work capacity is one of main problem to make optimal result. In case at the office, there are constraints to determine workload because of non-repetitive works. Employees do work based on the targets set in a working period. At the end of the period is usually performed an evaluation of employees performance to evaluate needs of employees. The aims of this study to design a workload questionnaire tools to evaluate the efficiency level of position as indicator to determine needs of employees based on the Indonesian State Employment Agency Regulation on workload analysis. This research is applied to State-Owned Enterprise PT. X by determining 3 positions as a pilot project. Position A is held by 2 employees, position B is held by 7 employees, and position C is held by 6 employees. From the calculation result, position A has an efficiency level of 1,33 or "very good", position B has an efficiency level of 1.71 or "enough", and position C has an efficiency level of 1.03 or "very good". The application of this tools giving suggestion the needs of employees of position A is 3 people, position B is 5 people, and position C is 6 people. The difference between the number of employees and the calculation result is then analyzed by interviewing the employees to get more data about personal perception. It can be concluded that this workload evaluation tools can be used as an alternative solution to evaluate needs of employees in office.
Domestic chores workload and depressive symptoms among children affected by HIV/AIDS in China
Yu, Yun; Li, Xiaoming; Zhang, Liying; Zhao, Junfeng; Zhao, Guoxiang; Zheng, Yu; Stanton, Bonita
2012-01-01
Limited data are available regarding the effects of domestic chores workload on psychological problems among children affected by HIV/AIDS in China. The current study aims to examine association between children’s depressive symptoms and the domestic chores workload (i.e., the frequency and the amount of time doing domestic chores). Data were derived from the baseline survey of a longitudinal study which investigated the impact of parental HIV/AIDS on psychological problems of children. A total of 1,449 children in family-based care were included in the analysis: 579 orphaned children who lost one or both parents due to AIDS, 466 vulnerable children living with one or both parents being infected with HIV, and 404 comparison children who did not have HIV/AIDS infected family members in their families. Results showed differences on domestic chores workload between children affected by HIV/AIDS (orphans and vulnerable children) and the comparison children. Children affected by HIV/AIDS worked more frequently and worked longer time on domestic chores than the comparison children. Multivariate linear regression analysis showed that domestic chores workload was positively associated with depressive symptoms. The data suggest that children affected by HIV/AIDS may face increasing burden of domestic chores and it is necessary to reduce the excessive workload of domestic chores among children affected by HIV/AIDS through increasing community-based social support for children in the families affected by HIV/AIDS. PMID:22970996
NASA Astrophysics Data System (ADS)
Michioka, Chishiro; Suzuki, Kazuya; Mibu, Ko
2002-10-01
We applied 57Fe Mössbauer spectroscopy for investigating the Ising spin triangular lattice antiferromagnet (TLA) (CeS)1.16[Fe0.33(NbS2)2] between 2 and 300 K. The spectra revealed that the relaxation time of the hyperfine field markedly changes in the intermediate phase between TN1=22 K and TN2=15 K due to strong spin fluctuation. The relaxation of the hyperfine field is not sufficiently fast as a paramagnet even at 77 K, which is much higher than TN1, and the inverse susceptibility of (LaS)1.14[Fe0.33(NbS2)2] deviates from the Curie-Weiss law below 100 K. These results indicate that an unusual short-range order exists above TN1. The temperature dependence of the Mössbauer spectra can be explained by phase transition of the three-dimensional TLA model with weak interlayer exchange interactions.
NASA Astrophysics Data System (ADS)
Aoyama, Takuya; Miyake, Atsushi; Kagayama, Tomoko; Shimizu, Katsuya; Kimura, Tsuyoshi
2013-03-01
Effects of high pressure exceeding 10 GPa on spin-driven ferroelectricity were investigated for a multiferroic, triangular-lattice antiferromagnet (TLA), CuCrO2. For this purpose, we developed a system which enables us to measure ferroelectric polarization under a pressure of 10 GPa by using a diamond anvil cell. We found that the magnetic transition temperature accompanying the ferroelectric one in CuCrO2 was remarkably enhanced by applying pressure. The result is simply explained by considering the pressure-induced enhancement of inter- and/or intralayer magnetic interaction due to the compression of the lattice. In addition, the coercive electric field for the polarization reversal was also increased with increasing pressure, while the amplitude of the ferroelectric polarization was steeply suppressed at around 8 GPa. A possible origin of the observed pressure effects on the ferroelectric property in the multiferroic TLA is discussed in terms of a ferroelectric-antiferroelectric transition and structural domain rearrangement by uniaxial stress.
Phase-noise influence on coherent transients and hole burning
NASA Astrophysics Data System (ADS)
Shakhmuratov, R. N.; Szabo, Alex
1998-10-01
Resonant excitation of an inhomogeneously broadened ensemble of two-level atoms (TLA) by a stochastic field with phase noise is theoretically investigated. Free-induction decay (FID), hole burning (HB), and transient nutation (TN) are studied. We consider two kinds of driving fields, one with a free walking phase and another with the phase locked in a limited domain. It is shown that the resonant excitation behavior depends strongly on the noise property. Noise induced by a walking phase gives a simple contribution to the dephasing time, T2, of two-level atoms whereas phase locking qualitatively changes the laser-atom interaction. In the latter case, it is shown that even when the central part of the driving field spectrum is narrower than homogeneous absorption line of the TLA, the wide, low intensity wings of the spectrum (sidebands produced by the locked phase noise), have a strong effect on the FID, TN, and HB induced by the central, narrow part of the spectrum. The influence of sidebands on photon echoes is also discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tsai, C.H.; Hsu, K.Y.; Kai, J.J.
1992-12-31
The surface layers of copper alloy specimens were made radioactive by bombarding with 5 MeV protons from a van de Graaff accelerator which converted Cu-65 into Zn-65 through (p,n) reaction. The amount of surface material loss could then be monitored by measuring the total remaining {gamma}-ray activity generated from Zn-65 decay. This technique, termed thin layer activation (TLA), has the advantage of in situ monitoring the rate of surface removal due to corrosion, erosion-corrosion, wearing, etc. In this work, the erosion-corrosion tests on aluminum brass and 90Cu-10Ni were conducted in circulating sea water and the erosion-corrosion rates measured using TLAmore » and conventional methods such as linear polarization resistance (LPR) method and weight loss coupons were compared. A vibrational cavitation-erosion test was also performed on aluminum bronze, in which the measurements by TLA were compared with those of weight loss measurements.« less
Associations between attending physician workload, teaching effectiveness, and patient safety.
Wingo, Majken T; Halvorsen, Andrew J; Beckman, Thomas J; Johnson, Matthew G; Reed, Darcy A
2016-03-01
Prior studies suggest that high workload among attending physicians may be associated with reduced teaching effectiveness and poor patient outcomes, but these relationships have not been investigated using objective measures of workload and safety. To examine associations between attending workload, teaching effectiveness, and patient safety, hypothesizing that higher workload would be associated with lower teaching effectiveness and negative patient outcomes. We conducted a retrospective study of 69,386 teaching evaluation items submitted by 543 internal medicine residents for 107 attending physicians who supervised inpatient teaching services from July 2, 2005 to July 1, 2011. Attending workload measures included hospital service census, patient length of stay, daily admissions, daily discharges, and concurrent outpatient duties. Teaching effectiveness was measured using residents' evaluations of attendings. Patient outcomes considered were applicable patient safety indicators (PSIs), intensive care unit transfers, cardiopulmonary resuscitation/rapid response team calls, and patient deaths. Mixed linear models and generalized linear regression models were used for statistical analysis. Workload measures of midnight census and daily discharges were associated with lower teaching evaluation scores (both β = -0.026, P < 0.0001). The number of daily admissions was associated with higher teaching scores (β = 0.021, P = 0.001) and increased PSIs (odds ratio = 1.81, P = 0.0001). Several measures of attending physician workload were associated with slightly lower teaching effectiveness, and patient safety may be compromised when teams are managing new admissions. Ongoing efforts by residency programs to optimize the learning environment should include strategies to manage the workload of supervising attendings. © 2016 Society of Hospital Medicine.
Performance Analysis of the NAS Y-MP Workload
NASA Technical Reports Server (NTRS)
Bergeron, Robert J.; Kutler, Paul (Technical Monitor)
1997-01-01
This paper describes the performance characteristics of the computational workloads on the NAS Cray Y-MP machines, a Y-MP 832 and later a Y-MP 8128. Hardware measurements indicated that the Y-MP workload performance matured over time, ultimately sustaining an average throughput of 0.8 GFLOPS and a vector operation fraction of 87%. The measurements also revealed an operation rate exceeding 1 per clock period, a well-balanced architecture featuring a strong utilization of vector functional units, and an efficient memory organization. Introduction of the larger memory 8128 increased throughput by allowing a more efficient utilization of CPUs. Throughput also depended on the metering of the batch queues; low-idle Saturday workloads required a buffer of small jobs to prevent memory starvation of the CPU. UNICOS required about 7% of total CPU time to service the 832 workloads; this overhead decreased to 5% for the 8128 workloads. While most of the system time went to service I/O requests, efficient scheduling prevented excessive idle due to I/O wait. System measurements disclosed no obvious bottlenecks in the response of the machine and UNICOS to the workloads. In most cases, Cray-provided software tools were- quite sufficient for measuring the performance of both the machine and operating, system.
Quantitative assessment of workload and stressors in clinical radiation oncology.
Mazur, Lukasz M; Mosaly, Prithima R; Jackson, Marianne; Chang, Sha X; Burkhardt, Katharin Deschesne; Adams, Robert D; Jones, Ellen L; Hoyle, Lesley; Xu, Jing; Rockwell, John; Marks, Lawrence B
2012-08-01
Workload level and sources of stressors have been implicated as sources of error in multiple settings. We assessed workload levels and sources of stressors among radiation oncology professionals. Furthermore, we explored the potential association between workload and the frequency of reported radiotherapy incidents by the World Health Organization (WHO). Data collection was aimed at various tasks performed by 21 study participants from different radiation oncology professional subgroups (simulation therapists, radiation therapists, physicists, dosimetrists, and physicians). Workload was assessed using National Aeronautics and Space Administration Task-Load Index (NASA TLX). Sources of stressors were quantified using observational methods and segregated using a standard taxonomy. Comparisons between professional subgroups and tasks were made using analysis of variance ANOVA, multivariate ANOVA, and Duncan test. An association between workload levels (NASA TLX) and the frequency of radiotherapy incidents (WHO incidents) was explored (Pearson correlation test). A total of 173 workload assessments were obtained. Overall, simulation therapists had relatively low workloads (NASA TLX range, 30-36), and physicists had relatively high workloads (NASA TLX range, 51-63). NASA TLX scores for physicians, radiation therapists, and dosimetrists ranged from 40-52. There was marked intertask/professional subgroup variation (P<.0001). Mental demand (P<.001), physical demand (P=.001), and effort (P=.006) significantly differed among professional subgroups. Typically, there were 3-5 stressors per cycle of analyzed tasks with the following distribution: interruptions (41.4%), time factors (17%), technical factors (13.6%), teamwork issues (11.6%), patient factors (9.0%), and environmental factors (7.4%). A positive association between workload and frequency of reported radiotherapy incidents by the WHO was found (r = 0.87, P value=.045). Workload level and sources of stressors vary among professional subgroups. Understanding the factors that influence these findings can guide adjustments to the workflow procedures, physical layout, and/or communication protocols to enhance safety. Additional evaluations are needed in order to better understand if these findings are systemic. Copyright © 2012 Elsevier Inc. All rights reserved.
Quantitative Assessment of Workload and Stressors in Clinical Radiation Oncology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mazur, Lukasz M., E-mail: lukasz_mazur@ncsu.edu; Industrial Extension Service, North Carolina State University, Raleigh, North Carolina; Biomedical Engineering, North Carolina State University, Raleigh, North Carolina
2012-08-01
Purpose: Workload level and sources of stressors have been implicated as sources of error in multiple settings. We assessed workload levels and sources of stressors among radiation oncology professionals. Furthermore, we explored the potential association between workload and the frequency of reported radiotherapy incidents by the World Health Organization (WHO). Methods and Materials: Data collection was aimed at various tasks performed by 21 study participants from different radiation oncology professional subgroups (simulation therapists, radiation therapists, physicists, dosimetrists, and physicians). Workload was assessed using National Aeronautics and Space Administration Task-Load Index (NASA TLX). Sources of stressors were quantified using observational methodsmore » and segregated using a standard taxonomy. Comparisons between professional subgroups and tasks were made using analysis of variance ANOVA, multivariate ANOVA, and Duncan test. An association between workload levels (NASA TLX) and the frequency of radiotherapy incidents (WHO incidents) was explored (Pearson correlation test). Results: A total of 173 workload assessments were obtained. Overall, simulation therapists had relatively low workloads (NASA TLX range, 30-36), and physicists had relatively high workloads (NASA TLX range, 51-63). NASA TLX scores for physicians, radiation therapists, and dosimetrists ranged from 40-52. There was marked intertask/professional subgroup variation (P<.0001). Mental demand (P<.001), physical demand (P=.001), and effort (P=.006) significantly differed among professional subgroups. Typically, there were 3-5 stressors per cycle of analyzed tasks with the following distribution: interruptions (41.4%), time factors (17%), technical factors (13.6%), teamwork issues (11.6%), patient factors (9.0%), and environmental factors (7.4%). A positive association between workload and frequency of reported radiotherapy incidents by the WHO was found (r = 0.87, P value=.045). Conclusions: Workload level and sources of stressors vary among professional subgroups. Understanding the factors that influence these findings can guide adjustments to the workflow procedures, physical layout, and/or communication protocols to enhance safety. Additional evaluations are needed in order to better understand if these findings are systemic.« less
Comparison of nurse staffing based on changes in unit-level workload associated with patient churn.
Hughes, Ronda G; Bobay, Kathleen L; Jolly, Nicholas A; Suby, Chrysmarie
2015-04-01
This analysis compares the staffing implications of three measures of nurse staffing requirements: midnight census, turnover adjustment based on length of stay, and volume of admissions, discharges and transfers. Midnight census is commonly used to determine registered nurse staffing. Unit-level workload increases with patient churn, the movement of patients in and out of the nursing unit. Failure to account for patient churn in staffing allocation impacts nurse workload and may result in adverse patient outcomes. Secondary data analysis of unit-level data from 32 hospitals, where nursing units are grouped into three unit-type categories: intensive care, intermediate care, and medical surgical. Midnight census alone did not account adequately for registered nurse workload intensity associated with patient churn. On average, units were staffed with a mixture of registered nurses and other nursing staff not always to budgeted levels. Adjusting for patient churn increases nurse staffing across all units and shifts. Use of the discharges and transfers adjustment to midnight census may be useful in adjusting RN staffing on a shift basis to account for patient churn. Nurse managers should understand the implications to nurse workload of various methods of calculating registered nurse staff requirements. © 2013 John Wiley & Sons Ltd.
Shengqian Zhang; Yuan Zhang; Yu Sun; Thakor, Nitish; Bezerianos, Anastasios
2017-07-01
The research field of mental workload has attracted abundant researchers as mental workload plays a crucial role in real-life performance and safety. While previous studies have examined the neural correlates of mental workload in 2D scenarios (i.e., presenting stimuli on a computer screen (CS) environment using univariate methods (e.g., EEG channel power), it is still unclear of the findings of one that uses multivariate approach using graphical theory and the effects of a 3D environment (i.e., presenting stimuli on a Virtual Reality (VR)). In this study, twenty subjects undergo flight simulation in both CS and VR environment with three stages each. After preprocessing, the Electroencephalogram (EEG) signals were a connectivity matrix based on Phase Lag Index (PLI) will be constructed. Graph theory analysis then will be applied based on their global efficiency, local efficiency and nodal efficiency on both alpha and theta band. For global efficiency and local efficiency, VR values are generally lower than CS in both bands. For nodal efficiency, the regions that show at least marginally significant decreases are very different for CS and VR. These findings suggest that 3D simulation effects a higher mental workload than 2D simulation and that they each involved a different brain region.
Nursing workload in intensive care unit trauma patients: analysis of associated factors.
Nogueira, Lilia de Souza; Domingues, Cristiane de Alencar; Poggetti, Renato Sérgio; de Sousa, Regina Marcia Cardoso
2014-01-01
From the perspective of nurses, trauma patients in the Intensive Care Unit (ICU) demand a high degree of nursing workload due to hemodynamic instability and the severity of trauma injuries. This study aims to identify the factors related to the high nursing workload required for trauma victims admitted to the ICU. This is a prospective, cross-sectional study using descriptive and correlation analyses, conducted with 200 trauma patients admitted to an ICU in the city of São Paulo, Brazil. The nursing workload was measured using the Nursing Activities Score (NAS). The distribution of the NAS values into tertiles led to the identification of two research groups: medium/low workload and high workload. The Chi-square, Fisher's exact, Mann-Whitney and multiple logistic regression tests were utilized for the analyses. The majority of patients were male (82.0%) and suffered blunt trauma (94.5%), with traffic accidents (57.5%) and falls (31.0%) being prevalent. The mean age was 40.7 years (± 18.6) and the mean NAS was 71.3% (± 16.9). Patient gender, the presence of pulmonary failure, the number of injured body regions and the risk of death according to the Simplified Acute Physiology Score II were factors associated with a high degree of nursing workload in the first 24 hours following admission to the ICU. Workload demand was higher in male patients with physiological instability and multiple severe trauma injuries who developed pulmonary failure.
Short-Term International Experiences and Teacher Language Awareness
ERIC Educational Resources Information Center
Harbon, Lesley
2007-01-01
This research study had as its focus the impact of a short-term international experience on teacher language awareness (TLA). In-country intensive immersion experiences were considered beneficial for language teacher professional development. This project examined the Australian teachers' perceptions of their teaching and home-stay experiences…
Basic statistics of PM2.5 and PM10 in the atmosphere of Mexico City.
Vega, E; Reyes, E; Sánchez, G; Ortiz, E; Ruiz, M; Chow, J; Watson, J; Edgerton, S
2002-03-27
The high levels of fine particulate matter in Mexico City are of concern since they may induce severe public health effects as well as the attenuation of visible light. Sequential filter samplers were used at six different sites from 23 February to 22 March 1997. The sampling campaign was carried out as part of the project 'Investigación sobre Materia Particulada y Deterioro Atmosferico-Aerosol and Visibility Evaluation Research'. This research was a cooperative project sponsored by PEMEX and by the US Department of Energy. Sampling sites represent the different land uses along the city, the northwest station, Tlalnepantla, is located in a mixed medium income residential and industrial area. The northeast station, Xalostoc, is located in a highly industrialized area, Netzahualcoyotl is located in a mixed land use area, mainly commercial and residential. Station La Merced is located in the commercial and administrative district downtown. The southwest station is located in the Pedregal de San Angel, in a high-income neighborhood, and the southeast station located in Cerro de la Estrella is a mixed medium income residential and commercial area. Samples were collected four times a day in Cerro de la Estrella (CES), La Merced (MER) and Xalostoc (XAL) with sampling periods of 6 h. In Pedregal (PED), Tlalnepantla (TLA) and Netzahualcoyot1 (NEZ) sampling periods were every 24 h. In this paper the basic statistics of PM2.5 and PM10 mass concentrations are presented. The average results showed that 49, 61, 46, 57, 51 and 44% of the PM10 consisted of PM2.5 for CES, MER, XAL, PED, TLA and NEZ, respectively. The 24-h average highest concentrations of PM25 and PM10 were registered at NEZ (184 and 267 microg/m3) and the lowest at PED (22 and 39 microg/m3). The highest PM10 correlations were between XAL-CES (0.79), PED-TLA (0.80). In contrast, the highest PM2.5 correlations were between CES-PED (0.74), MER-CES (0.73) and TLA-PED (0.72), showing a lower correlation than the PM10 one. The results of the PM10 from 12.00 to 18.00 h at CES and MER presented the highest variability and also the highest median concentrations, meanwhile XAL showed them from 06.00 to 12.00 h. The highest variability and median concentrations of PM2.5 were from 06.00 to 12.00 h for the three stations.
Holec-Gąsior, Lucyna; Ferra, Bartłomiej; Hiszczyńska-Sawicka, Elżbieta; Kur, Józef
2014-12-15
Toxoplasmosis, caused by Toxoplasma gondii, is the major parasitic disease affecting sheep. Infection not only results in significant reproductive losses in these animals, but has public health implications since consumption of infected meat can facilitate zoonotic transmission. Although several serological tests are currently used for diagnosis of ovine toxoplasmosis, production of reliable reagents is a constraint and therefore there is a need to develop new diagnostic tools. In this paper, we assess for the first time, the preliminary diagnostic utility of 19 T. gondii recombinant antigens (GRA1, GRA2ex2, GRA4, GRA5, GRA6, GRA9, SAG1, SAG4, BSR4, P22, ROP1, P36, MIC1ex2, MIC1ex34, MIC3, MAG1, BAG1, LDH1, and LDH2) in immunoglobulin G (IgG) enzyme-linked immunosorbent assays (IgG ELISAs). Following an initial evaluation, eight recombinant antigens (GRA1, GRA9, SAG1, SAG4, P22, MIC1ex2, MIC3, ROP1) were chosen for subsequent testing and comparison against the native Toxoplasma lysate antigen (TLA) in IgG ELISAs using 88 sera from naturally infected sheep and 20 sera from healthy animals. The reactivity of these antigens was variable with the best results for GRA1, P22, ROP1 and TLA. High sensitivity and specificity (100%) was noted for GRA1, ROP1 and TLA; P22 showed a slightly lower sensitivity (98.9%) but the same high specificity (100%). Four different combinations of these antigens (M1: GRA1+ROP1; M2: GRA1+P22; M3: P22+ROP1; M4: GRA1+P22+ROP1) were tested against the same pool of ovine sera; all IgG-positive serum samples were detected by all of the mixtures. However, the most effective for diagnosis of toxoplasmosis in sheep, based on the highest absorbance values, was the mixture M4 containing three proteins. High sensitivity and specificity (100%) was observed from tests containing either M4 or TLA antigens with a new pool of sera (93 seropositive and 35 seronegative). Thus, the present study shows that a cocktail of GRA1+P22+ROP1 recombinant proteins can be used to diagnose T. gondii infection in sheep, and consequently will assist in epidemiological studies. Copyright © 2014 Elsevier B.V. All rights reserved.
Mazur, Lukasz M; Mosaly, Prithima R; Hoyle, Lesley M; Jones, Ellen L; Marks, Lawrence B
2013-01-01
To quantify, and compare, workload for several common physician-based treatment planning tasks using objective and subjective measures of workload. To assess the relationship between workload and performance to define workload levels where performance could be expected to decline. Nine physicians performed the same 3 tasks on each of 2 cases ("easy" vs "hard"). Workload was assessed objectively throughout the tasks (via monitoring of pupil size and blink rate), and subjectively at the end of each case (via National Aeronautics and Space Administration Task Load Index; NASA-TLX). NASA-TLX assesses the 6 dimensions (mental, physical, and temporal demands, frustration, effort, and performance); scores > or ≈ 50 are associated with reduced performance in other industries. Performance was measured using participants' stated willingness to approve the treatment plan. Differences in subjective and objective workload between cases, tasks, and experience were assessed using analysis of variance (ANOVA). The correlation between subjective and objective workload measures were assessed via the Pearson correlation test. The relationships between workload and performance measures were assessed using the t test. Eighteen case-wise and 54 task-wise assessments were obtained. Subjective NASA-TLX scores (P < .001), but not time-weighted averages of objective scores (P > .1), were significantly lower for the easy vs hard case. Most correlations between the subjective and objective measures were not significant, except between average blink rate and NASA-TLX scores (r = -0.34, P = .02), for task-wise assessments. Performance appeared to decline at NASA-TLX scores of ≥55. The NASA-TLX may provide a reasonable method to quantify subjective workload for broad activities, and objective physiologic eye-based measures may be useful to monitor workload for more granular tasks within activities. The subjective and objective measures, as herein quantified, do not necessarily track each other, and more work is needed to assess their utilities. From a series of controlled experiments, we found that performance appears to decline at subjective workload levels ≥55 (as measured via NASA-TLX), which is consistent with findings from other industries. Copyright © 2013 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.
Needs Analysis of Employee in Riau Main Island: A Reflection from Universitas Lancang Kuning Context
NASA Astrophysics Data System (ADS)
Hasnati; Chintia Utami, Bunga; Saputra, Trio
2018-05-01
Performance of employees is a major concern for all organization. It’s depend on workload. The availability of staff in Lancang Kuning University which established in Riau Main island is not adjusted to the changing needs of the Organizational Structure and the workload of the employees. One preparation to Achieve the Strategic HR Planning Is that ripe with a set amount of human resources that is ideal to get UNILAK UNGGUL 2030. But, it will not happen if the distribution of employees have not Referred to the real needs of the organization. The distribution has not been based on the workload of the organization. Stacking employees in one unit without clear work and lack of staff in other units is a fact of the underlying problem at Lancang Kuning University. So in order to Achieve the performance of employees, we must to to be done structuring. In the implementation, Lancang Kuning University conducted an analysis of positions that include positions produce information Position Information Analysis. The purpose of this study is to projection of the Needed Employees with qualitative method. The research informants were selected from three institutions / units in the University of Lancang Kuning. The results of the workload analysis of staff at the University of Lancang Kuning can be done if there is clarity of guidelines or work instructions, a good understanding of the work guidelines to everyone, the suitability between work guidelines and knowledge of educational personnel. Based on job information and workloads, it is found that only two institutions are LPPM and BPM roomates is suitable of needs but in other side there are excess and lack, library excess 1 employee.
Predicting the Consequences of Workload Management Strategies with Human Performance Modeling
NASA Technical Reports Server (NTRS)
Mitchell, Diane Kuhl; Samma, Charneta
2011-01-01
Human performance modelers at the US Army Research Laboratory have developed an approach for establishing Soldier high workload that can be used for analyses of proposed system designs. Their technique includes three key components. To implement the approach in an experiment, the researcher would create two experimental conditions: a baseline and a design alternative. Next they would identify a scenario in which the test participants perform all their representative concurrent interactions with the system. This scenario should include any events that would trigger a different set of goals for the human operators. They would collect workload values during both the control and alternative design condition to see if the alternative increased workload and decreased performance. They have successfully implemented this approach for military vehicle. designs using the human performance modeling tool, IMPRINT. Although ARL researches use IMPRINT to implement their approach, it can be applied to any workload analysis. Researchers using other modeling and simulations tools or conducting experiments or field tests can use the same approach.
NASA Technical Reports Server (NTRS)
Eckel, J. S.; Crabtree, M. S.
1984-01-01
Analytical and subjective techniques that are sensitive to the information transmission and processing requirements of individual communications-related tasks are used to assess workload imposed on the aircrew by A-10 communications requirements for civilian transport category aircraft. Communications-related tasks are defined to consist of the verbal exchanges between crews and controllers. Three workload estimating techniques are proposed. The first, an information theoretic analysis, is used to calculate bit values for perceptual, manual, and verbal demands in each communication task. The second, a paired-comparisons technique, obtains subjective estimates of the information processing and memory requirements for specific messages. By combining the results of the first two techniques, a hybrid analytical scale is created. The third, a subjective rank ordering of sequences of communications tasks, provides an overall scaling of communications workload. Recommendations for future research include an examination of communications-induced workload among the air crew and the development of simulation scenarios.
NASA Astrophysics Data System (ADS)
Yokoi, Toshiyuki; Itoh, Michimasa; Oguri, Koji
Most of the traffic accidents have been caused by inappropriate driver's mental state. Therefore, driver monitoring is one of the most important challenges to prevent traffic accidents. Some studies for evaluating the driver's mental state while driving have been reported; however driver's mental state should be estimated in real-time in the future. This paper proposes a way to estimate quantitatively driver's mental workload using heart rate variability. It is assumed that the tolerance to driver's mental workload is different depending on the individual. Therefore, we classify people based on their individual tolerance to mental workload. Our estimation method is multiple linear regression analysis, and we compare it to NASA-TLX which is used as the evaluation method of subjective mental workload. As a result, the coefficient of correlation improved from 0.83 to 0.91, and the standard deviation of error also improved. Therefore, our proposed method demonstrated the possibility to estimate mental workload.
Jørgensen, Marie Birk; Nabe-Nielsen, Kirsten; Clausen, Thomas; Holtermann, Andreas
2013-03-15
Prospective cohort study. To investigate the independent effect of physical workload and childhood socioeconomic status (CSES) on low back pain (LBP) and LBP-related sickness absence among female health care workers. The role of physical workload on LBP independently from CSES is still subject to controversy. We used questionnaire data from 1661 female social and health care workers responding to a questionnaire in 2004, 2005, and 2006. We collected information on CSES (parental occupation), physical workload, and LBP-prevalence (no LBP, subchronic LBP, and frequent LBP), and LBP-related sickness absence. The participants were categorized into 5 groups according to CSES (I = highest, V = lowest). Data were analyzed using logistic regression analysis. Irrespective of CSES, high physical workload increased the odds ratio (OR) of future subchronic LBP (OR = 2.03; 95% confidence interval [CI], 1.61-2.57) and frequent LBP (OR = 2.20; 95% CI, 1.65-3.00), but not LBP-related sickness absence. The odds of subchronic LBP were lower in CSES groups II (OR = 0.62; 95% CI, 0.42-0.93) and III (OR = 0.58; 95% CI, 0.39-0.86) referencing CSES group I, irrespective of physical workload. The odds of short-term LBP-related sickness absence were higher in CSES groups III (OR = 2.78; 95% CI, 1.41-5.47) and IV (OR = 2.18; 95% CI, 1.11-4.27) referencing CSES group I, irrespective of physical workload. We found no interaction between physical workload and CSES. Physical workload and CSES are independently associated with future LBP within a group with similar occupational status. N/A.
NASA Technical Reports Server (NTRS)
Acton, W. H.; Crabtree, M. S.; Simons, J. C.; Gomer, F. E.; Eckel, J. S.
1983-01-01
Information theoretic analysis and subjective paired-comparison and task ranking techniques were employed in order to scale the workload of 20 communications-related tasks frequently performed by the captain and first officer of transport category aircraft. Tasks were drawn from taped conversations between aircraft and air traffic controllers (ATC). Twenty crewmembers performed subjective message comparisons and task rankings on the basis of workload. Information theoretic results indicated a broad range of task difficulty levels, and substantial differences between captain and first officer workload levels. Preliminary subjective data tended to corroborate these results. A hybrid scale reflecting the results of both the analytical and the subjective techniques is currently being developed. The findings will be used to select representative sets of communications for use in high fidelity simulation.
Measurement and analysis of workload effects on fault latency in real-time systems
NASA Technical Reports Server (NTRS)
Woodbury, Michael H.; Shin, Kang G.
1990-01-01
The authors demonstrate the need to address fault latency in highly reliable real-time control computer systems. It is noted that the effectiveness of all known recovery mechanisms is greatly reduced in the presence of multiple latent faults. The presence of multiple latent faults increases the possibility of multiple errors, which could result in coverage failure. The authors present experimental evidence indicating that the duration of fault latency is dependent on workload. A synthetic workload generator is used to vary the workload, and a hardware fault injector is applied to inject transient faults of varying durations. This method makes it possible to derive the distribution of fault latency duration. Experimental results obtained from the fault-tolerant multiprocessor at the NASA Airlab are presented and discussed.
Creating a Culture of Language Awareness in Content-Based Contexts
ERIC Educational Resources Information Center
Lindahl, Kristen; Watkins, Naomi M.
2015-01-01
A "toolkit" approach to professional development is frequently used to assist teachers of English language learners (ELLs), wherein teachers are provided a grab bag of activities and strategies to implement in their classrooms. However, today's heightened language demands call for teachers to develop teacher language awareness (TLA), a…
Language Learning Strategies of Multilingual Adults Learning Additional Languages
ERIC Educational Resources Information Center
Dmitrenko, Violetta
2017-01-01
The main goal consisted in identifying and bringing together strategies of multilinguals as a particular learner group. Therefore, research was placed in the intersection of the three fields: language learning strategies (LLS), third language acquisition (TLA), and the didactics of plurilingualism. First, the paper synthesises the major findings…
Entrepreneurship. Technology Learning Activity. Teacher Edition. Technology Education Series.
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This packet of technology learning activity (TLA) materials on entrepreneurship for students in grades 6-10 consists of a technology education overview, information on use, and instructor's and student's sections. The overview discusses the technology education program and materials. Components of the instructor's and student's sections are…
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This packet of technology learning activity (TLA) materials on introduction to animation for students in grades 6-10 consists of a technology education overview, information on use, and the instructor's and student's sections. The overview discusses the technology education program and materials. Section components are described next. The…
Audiovisual Programming. Technology Learning Activity. Teacher Edition. Technology Education Series.
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This packet of technology learning activity (TLA) materials on audiovisual programming for students in grades 6-10 consists of a technology education overview, information on use, and the instructor's and student's sections. The overview discusses the technology education program and materials. Components of the instructor's and student's sections…
Health Occupations. Technology Learning Activity. Teacher Edition. Technology Education Series.
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This packet of technology learning activity (TLA) materials on health occupations for students in grades 6-10 consists of a technology education overview, information on use, and instructor's and student's sections. The overview discusses the technology education program and materials. Components of the instructor's and student's sections are…
Electronic Publishing. Technology Learning Activity. Teacher Edition. Technology Education Series.
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This packet of technology learning activity (TLA) materials on electronic publishing for students in grades 6-10 consists of a technology education overview, information on use, and the instructor's and student's sections. The overview discusses the technology education program and materials. Components of the instructor and student sections are…
A nuclear scanning method for estimating wear level nonuniformities
NASA Astrophysics Data System (ADS)
Ivanov, E. A.; Pascovici, G.; Racolta, P. M.
1993-09-01
The residual radioactivity measuring method has been upgraded to estimate wear level nonuniformities in the circumference of a piston ring after a certain working time in the combustion engine testing bench. The piston ring was irradiated by the thin layer activation (TLA) technique and its radioactivity was continuously monitored.
L3 Acquisition of German Adjectival Inflection: A Generative Account
ERIC Educational Resources Information Center
Jaensch, Carol
2011-01-01
Studies testing the knowledge of syntactic properties have resulted in two potentially contrasting proposals in relation to third language acquisition (TLA); the Cumulative Enhancement Model (Flynn et al., 2004), which proposes that previously learned languages will positively affect the acquisition of a third language (L3); and the "second…
Career Search. Technology Learning Activity. Teacher Edition. Technology Education Series.
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This packet of technology learning activity (TLA) materials on career search for students in grades 6-10 consists of a technology education overview, information on use, and the instructor's and student's sections. The overview discusses the technology education program and materials. Components of the instructor's and student's sections are…
2014-01-01
Background Toxoplasmosis, caused by the obligate intracellular parasite Toxoplasma gondii, is an important zoonotic disease worldwide. The precise detection of T. gondii infection in dogs has important public health significance. In this study, recombinant granule antigen proteins GRA1 and GRA7 were evaluated as potential diagnostic markers for T. gondii infection in dogs by an indirect enzyme-linked immunosorbent assay (ELISA). Results GRA1 and GRA7 were cloned and expressed in Escherichia coli, and the recombinant GRA1, GRA7- and Toxoplasma lysate antigen (TLA)-based ELISAs were developed and evaluated using the canine positive and negative serum samples for anti-T. gondii antibodies determined by modified agglutination test (MAT) and indirect fluorescent antibody test (IFAT), showing a seroprevalence of 15.1% by TLA- and GRA1-ELISA, and 15.8% by GRA7-ELISA, and no significant difference was observed (P > 0.05). When compared with the two reference assays, MAT and IFAT, the GRA7-ELISA showed the highest co-positivity and co-negativity rates. Receiver operating characteristic (ROC) analysis revealed a largest area under curve (AUC) of 0.973 (95% CI, 0.955 to 0.991), and a highest relative sensitivity (93.2%) and specificity (94.0%) for a cut-off value of 0.809 in GRA7-ELISA. Conclusions The results of the present study showed that GRA7-ELISA is highly sensitive and specific, and GRA7 is a potential serodiagnostic marker for the detection of T. gondii infection in dogs. PMID:25016474
Statistical Abstracts, Fall 1990: Instructional Workload, Faculty, and I&DR Costs.
ERIC Educational Resources Information Center
State Univ. of New York, Albany. Central Staff Office of Institutional Research.
This publication provides summary analytical reports and graphic displays from the official Course and Section Analysis (CASA) system concerning the instructional workload and the financial resources of academic departments offering courses during the fall 1990 semester within the State University of New York system. Included are six reports. The…
Does daily nurse staffing match ward workload variability? Three hospitals' experiences.
Gabbay, Uri; Bukchin, Michael
2009-01-01
Nurse shortage and rising healthcare resource burdens mean that appropriate workforce use is imperative. This paper aims to evaluate whether daily nursing staffing meets ward workload needs. Nurse attendance and daily nurses' workload capacity in three hospitals were evaluated. Statistical process control was used to evaluate intra-ward nurse workload capacity and day-to-day variations. Statistical process control is a statistics-based method for process monitoring that uses charts with predefined target measure and control limits. Standardization was performed for inter-ward analysis by converting ward-specific crude measures to ward-specific relative measures by dividing observed/expected. Two charts: acceptable and tolerable daily nurse workload intensity, were defined. Appropriate staffing indicators were defined as those exceeding predefined rates within acceptable and tolerable limits (50 percent and 80 percent respectively). A total of 42 percent of the overall days fell within acceptable control limits and 71 percent within tolerable control limits. Appropriate staffing indicators were met in only 33 percent of wards regarding acceptable nurse workload intensity and in only 45 percent of wards regarding tolerable workloads. The study work did not differentiate crude nurse attendance and it did not take into account patient severity since crude bed occupancy was used. Double statistical process control charts and certain staffing indicators were used, which is open to debate. Wards that met appropriate staffing indicators prove the method's feasibility. Wards that did not meet appropriate staffing indicators prove the importance and the need for process evaluations and monitoring. Methods presented for monitoring daily staffing appropriateness are simple to implement either for intra-ward day-to-day variation by using nurse workload capacity statistical process control charts or for inter-ward evaluation using standardized measure of nurse workload intensity. The real challenge will be to develop planning systems and implement corrective interventions such as dynamic and flexible daily staffing, which will face difficulties and barriers. The paper fulfils the need for workforce utilization evaluation. A simple method using available data for daily staffing appropriateness evaluation, which is easy to implement and operate, is presented. The statistical process control method enables intra-ward evaluation, while standardization by converting crude into relative measures enables inter-ward analysis. The staffing indicator definitions enable performance evaluation. This original study uses statistical process control to develop simple standardization methods and applies straightforward statistical tools. This method is not limited to crude measures, rather it uses weighted workload measures such as nursing acuity or weighted nurse level (i.e. grade/band).
Liu, Y; Wickens, C D
1994-11-01
The evaluation of mental workload is becoming increasingly important in system design and analysis. The present study examined the structure and assessment of mental workload in performing decision and monitoring tasks by focusing on two mental workload measurements: subjective assessment and time estimation. The task required the assignment of a series of incoming customers to the shortest of three parallel service lines displayed on a computer monitor. The subject was either in charge of the customer assignment (manual mode) or was monitoring an automated system performing the same task (automatic mode). In both cases, the subjects were required to detect the non-optimal assignments that they or the computer had made. Time pressure was manipulated by the experimenter to create fast and slow conditions. The results revealed a multi-dimensional structure of mental workload and a multi-step process of subjective workload assessment. The results also indicated that subjective workload was more influenced by the subject's participatory mode than by the factor of task speed. The time estimation intervals produced while performing the decision and monitoring tasks had significantly greater length and larger variability than those produced while either performing no other tasks or performing a well practised customer assignment task. This result seemed to indicate that time estimation was sensitive to the presence of perceptual/cognitive demands, but not to response related activities to which behavioural automaticity has developed.
Measurement of Workload: Physics, Psychophysics, and Metaphysics
NASA Technical Reports Server (NTRS)
Gopher, D.
1984-01-01
The present paper reviews the results of two experiments in which workload analysis was conducted based upon performance measures, brain evoked potentials and magnitude estimations of subjective load. The three types of measures were jointly applied to the description of the behavior of subjects in a wide battery of experimental tasks. Data analysis shows both instances of association and dissociation between types of measures. A general conceptual framework and methodological guidelines are proposed to account for these findings.
2014-01-01
Background There is growing interest in integration of HIV and sexual and reproductive health (SRH) services as a way to improve the efficiency of human resources (HR) for health in low- and middle-income countries. Although this is supported by a wealth of evidence on the acceptability and clinical effectiveness of service integration, there is little evidence on whether staff in general health services can easily absorb HIV services. Methods We conducted a descriptive analysis of HR integration through task shifting/sharing and staff workload in the context of the Integra Initiative - a large-scale five-year evaluation of HIV/SRH integration. We describe the level, characteristics and changes in HR integration in the context of wider efforts to integrate HIV/SRH, and explore the impact of HR integration on staff workload. Results Improvements in the range of services provided by staff (HR integration) were more likely to be achieved in facilities which also improved other elements of integration. While there was no overall relationship between integration and workload at the facility level, HIV/SRH integration may be most influential on staff workload for provider-initiated HIV testing and counselling (PITC) and postnatal care (PNC) services, particularly where HIV care and treatment services are being supported with extra SRH/HIV staffing. Our findings therefore suggest that there may be potential for further efficiency gains through integration, but overall the pace of improvement is slow. Conclusions This descriptive analysis explores the effect of HIV/SRH integration on staff workload through economies of scale and scope in high- and medium-HIV prevalence settings. We find some evidence to suggest that there is potential to improve productivity through integration, but, at the same time, significant challenges are being faced, with the pace of productivity gain slow. We recommend that efforts to implement integration are assessed in the broader context of HR planning to ensure that neither staff nor patients are negatively impacted by integration policy. PMID:25103923
Sweeney, Sedona; Obure, Carol Dayo; Terris-Prestholt, Fern; Darsamo, Vanessa; Michaels-Igbokwe, Christine; Muketo, Esther; Nhlabatsi, Zelda; Warren, Charlotte; Mayhew, Susannah; Watts, Charlotte; Vassall, Anna
2014-08-07
There is growing interest in integration of HIV and sexual and reproductive health (SRH) services as a way to improve the efficiency of human resources (HR) for health in low- and middle-income countries. Although this is supported by a wealth of evidence on the acceptability and clinical effectiveness of service integration, there is little evidence on whether staff in general health services can easily absorb HIV services. We conducted a descriptive analysis of HR integration through task shifting/sharing and staff workload in the context of the Integra Initiative - a large-scale five-year evaluation of HIV/SRH integration. We describe the level, characteristics and changes in HR integration in the context of wider efforts to integrate HIV/SRH, and explore the impact of HR integration on staff workload. Improvements in the range of services provided by staff (HR integration) were more likely to be achieved in facilities which also improved other elements of integration. While there was no overall relationship between integration and workload at the facility level, HIV/SRH integration may be most influential on staff workload for provider-initiated HIV testing and counselling (PITC) and postnatal care (PNC) services, particularly where HIV care and treatment services are being supported with extra SRH/HIV staffing. Our findings therefore suggest that there may be potential for further efficiency gains through integration, but overall the pace of improvement is slow. This descriptive analysis explores the effect of HIV/SRH integration on staff workload through economies of scale and scope in high- and medium-HIV prevalence settings. We find some evidence to suggest that there is potential to improve productivity through integration, but, at the same time, significant challenges are being faced, with the pace of productivity gain slow. We recommend that efforts to implement integration are assessed in the broader context of HR planning to ensure that neither staff nor patients are negatively impacted by integration policy.
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.
Internal consistency and validity of a new physical workload questionnaire
Bot, S; Terwee, C; van der Windt, D A W M; Feleus, A; Bierma-Zeinstra, S; Knol, D; Bouter, L; Dekker, J
2004-01-01
Aims: To examine the dimensionality, internal consistency, and construct validity of a new physical workload questionnaire in employees with musculoskeletal complaints. Methods: Factor analysis was applied to the responses in three study populations with musculoskeletal disorders (n = 406, 300, and 557) on 26 items related to physical workload. The internal consistency of the resulting subscales was examined. It was hypothesised that physical workload would vary among different occupational groups. The occupations of all subjects were classified into four groups on the basis of expected workload (heavy physical load; long lasting postures and repetitive movements; both; no physical load). Construct validity of the subscales created was tested by comparing the subscale scores among these occupational groups. Results: The pattern of the factor loadings of items was almost identical for the three study populations. Two interpretable factors were found: items related to heavy physical workload loaded highly on the first factor, and items related to static postures or repetitive work loaded highly on the second factor. The first constructed subscale "heavy physical work" had a Cronbach's α of 0.92 to 0.93 and the second subscale "long lasting postures and repetitive movements", of 0.86 to 0.87. Six of eight hypotheses regarding the construct validity of the subscales were confirmed. Conclusions: The results support the internal structure, internal consistency, and validity of the new physical workload questionnaire. Testing this questionnaire in non-symptomatic employees and comparing its performance with objective assessments of physical workload are important next steps in the validation process. PMID:15550603
Lasers. Technology Learning Activity. Teacher Edition. Technology Education Series.
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This document contains the materials required for presenting an 8-day competency-based technology learning activity (TLA) designed to introduce students in grades 6-10 to advances and career opportunities in the field of laser technology. The guide uses a series of hands-on exploratory experiences into which activities to help students develop…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-06
... System Web site at https://edis.usitc.gov . Failure to comply with the requirements of this chapter and... Electronic Document Information System (EDIS) already accepts electronic filing of certain documents, and..., regardless of whether the electronic docketing system is operational. The ITC TLA makes a similar comment...
Aerospace and Flight. Technology Learning Activity. Teacher Edition. Technology Education Series.
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This packet of technology learning activity (TLA) materials on aerospace and flight for students in grades 6-10 consists of a technology education overview, information on use, and instructor's and student's sections. The overview discusses the technology education program and materials. Components of the instructor's and student's sections are…
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This document contains the materials required for presenting an 8-day competency-based technology learning activity (TLA) designed to introduce students in grades 6-10 to advances and career opportunities in the field of robotics-control technology. The guide uses hands-on exploratory experiences into which activities to help students develop…
Drafting. Technology Learning Activity. Teacher Edition. Technology Education Series.
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This packet of technology learning activity (TLA) materials for drafting for students in grades 6-10 consists of an instructor's section and student materials. The instructor's section contains background information, suggested activities, and a list of suggested resources. A lesson plan for the 8-day module includes assignments; equipment, tools,…
Agriculture Education SimFarm(TM). Technology Learning Activity. Teacher Edition.
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This Technology Learning Activity (TLA) for agriculture education in grades 6-10 is designed to help students learn the basic terminology of a farm system while they experience the responsibility of keeping a profitable farm in operation through use of the interactive SimFarm software. Introductory materials provide an overview of technology…
Control Robotics Programming Technology. Technology Learning Activity. Teacher Edition.
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This Technology Learning Activity (TLA) for control robotics programming technology in grades 6-10 is designed to teach students to construct and program computer-controlled devices using a LEGO DACTA set and computer interface and to help them understand how control technology and robotics affect them and their lifestyle. The suggested time for…
atlant: Advanced Three Level Approximation for Numerical Treatment of Cosmological Recombination
NASA Astrophysics Data System (ADS)
Kholupenko, E. E.; Ivanchik, A. V.; Balashev, S. A.; Varshalovich, D. A.
2011-10-01
atlant is a public numerical code for fast calculations of cosmological recombination of primordial hydrogen-helium plasma is presented. This code is based on the three-level approximation (TLA) model of recombination and allows us to take into account some "fine" physical effects of cosmological recombination simultaneously with using fudge factors.
Communication via Chalkboard and on Paper. TLA-100.00 (F.U.F.).
ERIC Educational Resources Information Center
Hardison, Margaret J.
The purpose of this cluster of learning modules is to increase the teacher intern's understanding and skills with regard to his role as a communicator. The cluster contains three modules: (a) objectives for teaching handwriting, (b) methodology of manuscript writing, and (c) practice teaching of manuscript handwriting. Each module contains a…
Effective Grammar Teaching: Lessons from Confident Grammar Teachers
ERIC Educational Resources Information Center
Petraki, Eleni; Hill, Deborah
2011-01-01
Learning the grammar of a language is an integral part of learning a second or foreign language. Studies on teacher beliefs, teacher language awareness (TLA) and grammar teaching have reported that the majority of English language teachers recognise the importance of teaching grammar (Borg, 2001; Borg & Burns, 2008). At the same time, many…
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This packet of technology learning activity (TLA) materials for residential construction for students in grades 6-10 consists of an instructor's section and student materials. The instructor's section contains background information, suggested activities, and a list of suggested resources. A lesson plan for the 10-day module includes assignments;…
Submegabase Clusters of Unstable Tandem Repeats Unique to the Tla Region of Mouse T Haplotypes
Uehara, H.; Ebersole, T.; Bennett, D.; Artzt, K.
1990-01-01
We describe here the identification and genomic organization of mouse t haplotype-specific elements (TSEs) 7.8 and 5.8 kb in length. The TSEs exist as submegabase-long clusters of tandem repeats localized in the Tla region of the major histocompatibility complex of all t haplotype chromosomes examined. In contrast, no such clusters were detected among 12 inbred strains of Mus musculus and other Mus species; thus, clusters of TSEs represent the first absolutely qualitative difference between t haplotypes and wild-type chromosomes. Pulsed field gel electrophoresis shows that the number of clusters, and the number of repeats in each cluster are extremely variable. Dramatic quantitative differences of TSEs uniquely distinguish every independent t haplotype from any other. The complete nucleotide sequence of one 7.8-kb TSE reveals significant homology to the ETn (a major transcript in the early embryo of the mouse), and some homologies to intracisternal A-particles and the mammary tumor virus env gene. Apart from the diagnostic relevance to t haplotypes, evolutionary and functional significances are discussed with respect to chromosome structure and genetic recombination. PMID:2076812
Spin-polarized density-matrix functional theory of the single-impurity Anderson model
NASA Astrophysics Data System (ADS)
Töws, W.; Pastor, G. M.
2012-12-01
Lattice density functional theory (LDFT) is used to investigate spin excitations in the single-impurity Anderson model. In this method, the single-particle density matrix γijσ with respect to the lattice sites replaces the wave function as the basic variable of the many-body problem. A recently developed two-level approximation (TLA) to the interaction-energy functional W[γ] is extended to systems having spin-polarized density distributions and bond orders. This allows us to investigate the effect of external magnetic fields and, in particular, the important singlet-triplet gap ΔE, which determines the Kondo temperature. Applications to finite Anderson rings and square lattices show that the gap ΔE as well as other ground-state and excited-state properties are very accurately reproduced. One concludes that the spin-polarized TLA is reliable in all interaction regimes, from weak to strong correlations, for different hybridization strengths and for all considered impurity valence states. In this way the efficiency of LDFT to account for challenging electron-correlation effects is demonstrated.
Spin chirality and polarised neutron scattering
NASA Astrophysics Data System (ADS)
Plakhty, V. P.; Maleyev, S. V.; Kulda, J.; Visser, E. D.; Wosnitza, J.; Moskvin, E. V.; Brückel, Th.; Kremer, R. K.
2001-03-01
Possibilities of polarised neutrons in studies of chiral criticality are discussed. The critical exponents β C of the average chirality below TN, as well as φ C=β C+γ C and, therefore, γ C of the chiral susceptibility above TN are determined for a XY triangular lattice antiferromagnet (TLA) CsMnBr3: β C=0.44(2) , γ C=0.84(7) . The critical behaviour of the chirality that orders at TN with a relative precision of 5×10 -4 proves that the phase transition belongs to a new chiral universality class. For the TLA CsNiCl 3 ( S=1) we found in the XY region ( B=3 T) φ C=1.24(7) in agreement with the Monte-Carlo value φ C=1.22(6) for the chiral universality class. In the easy-axis region at B=1 T, φ C=0.54(4) , and the Haldane excitations are observed in the polarisation-dependent inelastic cross section above TN. The helimagnet holmium exhibits a different chiral criticality with φ C=1.56(5) , essentially higher than for TLAs.
Cyclotron accelerated beams applied in wear and corrosion studies
NASA Astrophysics Data System (ADS)
Racolta, P. M.; Popa-Simil, L.; Ivanov, E. A.; Alexandreanu, B.
1996-05-01
Wear and corrosion processes are characterized by a loss of material that is, for machine parts and components, usually in a micrometer's range. That is why, in the last two decades, many direct applications in machine construction, petrochemical and metallurgical industries based on the Thin Layer Activation (TLA) technique have been developed. In this paper general working patterns together with a few examples of TLA applications carried out using our laboratory's U-120 Cyclotron are presented. The relation between the counting rate of the radiation originating from the component's irradiated zone and the loss of the worn material can be determined mainly by two methods: the oil circulation method and the remnant radioactivity measuring method. The first method is illustrated with some typical examples such as the optimization of the running-in program of a diesel engine and anti-wear features certifying of lubricant oils. There is also presented an example where the second method mentioned above has been applied to corrosion rate determinations for different kinds of unoxidable steels used in inert gas generator construction.
Shakouri, Mahmoud; Ikuma, Laura H; Aghazadeh, Fereydoun; Punniaraj, Karthy; Ishak, Sherif
2014-10-01
This paper investigates the effect of changing work zone configurations and traffic density on performance variables and subjective workload. Data regarding travel time, average speed, maximum percent braking force and location of lane changes were collected by using a full size driving simulator. The NASA-TLX was used to measure self-reported workload ratings during the driving task. Conventional lane merge (CLM) and joint lane merge (JLM) were modeled in a driving simulator, and thirty participants (seven female and 23 male), navigated through the two configurations with two levels of traffic density. The mean maximum braking forces was 34% lower in the JLM configuration, and drivers going through the JLM configuration remained in the closed lane longer. However, no significant differences in speed were found between the two merge configurations. The analysis of self-reported workload ratings show that participants reported 15.3% lower total workload when driving through the JLM. In conclusion, the implemented changes in the JLM make it a more favorable merge configuration in both high and low traffic densities in terms of optimizing traffic flow by increasing the time and distance cars use both lanes, and in terms of improving safety due to lower braking forces and lower reported workload. Copyright © 2014 Elsevier Ltd. All rights reserved.
Counting the cost of social disadvantage in primary care: retrospective analysis of patient data.
Worrall, A; Rea, J N; Ben-Shlomo, Y
1997-01-04
To cost the relation between socioeconomic status and various measures of primary care workload and assess the adequacy of current "deprivation" payments in relation to actual costings for patients living in qualifying areas. Retrospective data on primary care were collected over a 4.5 year period from both computerised and manually filed records. Standardised data on socioeconomic status were obtained by postal questionnaire. Inner city group practice with a socioeconomically diverse population. 382 male and female subjects of all ages, with a total of 1296 person years of observation. Primary care costs resulting from consultations with a general practitioner or a practice nurse and both new and repeat prescriptions. Morbidity, workload, and costs of drug treatment increased with decreasing socioeconomic status. The difference in cost for patients in social classes IV and V combined compared with those in I and II combined was about 150 Pounds per person year at risk (47 Pounds for workload and 103 Pounds for drugs). Deprivation payments met only half the extra workload cost for patients from qualifying wards. The greater workload caused by social disadvantage has been previously underestimated by simple consultation rates. The absolute difference in costs for socially disadvantaged patients increase as more detailed measures of workload and drug treatment are included. Current deprivation payments only partially offset the increased expenditure on workload. This shortfall will have to be addressed to attract general practitioners to, or retain them in, deprived areas.
Task sharing in Zambia: HIV service scale-up compounds the human resource crisis.
Walsh, Aisling; Ndubani, Phillimon; Simbaya, Joseph; Dicker, Patrick; Brugha, Ruairí
2010-09-17
Considerable attention has been given by policy makers and researchers to the human resources for health crisis in Africa. However, little attention has been paid to quantifying health facility-level trends in health worker numbers, distribution and workload, despite growing demands on health workers due to the availability of new funds for HIV/AIDS control scale-up. This study analyses and reports trends in HIV and non-HIV ambulatory service workloads on clinical staff in urban and rural district level facilities. Structured surveys of health facility managers, and health services covering 2005-07 were conducted in three districts of Zambia in 2008 (two urban and one rural), to fill this evidence gap. Intra-facility analyses were conducted, comparing trends in HIV and non-HIV service utilisation with staff trends. Clinical staff (doctors, nurses and nurse-midwives, and clinical officers) numbers and staff population densities fell slightly, with lower ratios of staff to population in the rural district. The ratios of antenatal care and family planning registrants to nurses/nurse-midwives were highest at baseline and increased further at the rural facilities over the three years, while daily outpatient department (OPD) workload in urban facilities fell below that in rural facilities. HIV workload, as measured by numbers of clients receiving antiretroviral treatment (ART) and prevention of mother to child transmission (PMTCT) per facility staff member, was highest in the capital city, but increased rapidly in all three districts. The analysis suggests evidence of task sharing, in that staff designated by managers as ART and PMTCT workers made up a higher proportion of frontline service providers by 2007. This analysis of workforce patterns across 30 facilities in three districts of Zambia illustrates that the remarkable achievements in scaling-up HIV/AIDS service delivery has been on the back of sustained non-HIV workload levels, increasing HIV workload and stagnant health worker numbers. The findings are based on an analysis of routine data that are available to district and national managers. Mixed methods research is needed, combining quantitative analyses of routine health information with follow-up qualitative interviews, to explore and explain workload changes, and to identify and measure where problems are most acute, so that decision makers can respond appropriately. This study provides quantitative evidence of a human resource crisis in health facilities in Zambia, which may be more acute in rural areas.
Use of a CCD camera for the thermographic study of a transient liquid phase bonding process in steel
NASA Astrophysics Data System (ADS)
Castro, Eduardo H.; Epelbaum, Carlos; Carnero, Angel; Arcondo, Bibiana
2001-03-01
The bonding of steel pieces and the development of novel soldering methods, appropriate to the extended variety of applications of steels nowadays, bring the sensing of temperature an outstanding role in any metallurgical process. Transient liquid phase bonding (TLPB) processes have been successfully employed to join metals, among them steels. A thin layer of metal A, with a liquids temperature TLA, is located between two pieces of metal B, with a liquids temperature TLB higher than TLA. The joining zone is heated up to a temperature T(TLA
T-wave loop area from a pre-implant 12-lead ECG is associated with appropriate ICD shocks
Hnatkova, Katerina; Friede, Tim; Malik, Marek; Zabel, Markus
2017-01-01
Aims In implantable cardioverter-defibrillator (ICD) patients, predictors of ICD shocks and mortality are needed to improve patient selection. Electrocardiographic (ECG) markers are simple to obtain and have been demonstrated to predict mortality. We aimed to assess the association of T-wave loop area and circularity with ICD shocks. Methods The study investigated patients with ICDs implanted between 1998 and 2010 for whom digital 12-lead ECGs (Schiller CS200 ECG-Network) of sufficient quality were obtained within 1 month prior to the implantation. T-wave loop area and circularity were calculated. Follow-up data of appropriate shocks were obtained during ICD clinic visits that included reviews of device stored electrograms. Results A total of 605 patients (82% males) were included; 68% had ischemic cardiomyopathy and 72% were treated for primary prevention. Over 3.8±1.4 years of follow-up, 114 patients (19%) experienced appropriate shock(s). Those with smaller T-wave loop area received fewer shocks (TLA, hazard ratio, HR, per increase of 1 technical unit, 0.71; [95% confidence interval, 0.53–0.94]; P = 0.02) and those with larger T-wave loop circularity (TLC) representing rounder T wave loop received more shocks (HR per 1% TLC increase 2.96; [0.85–10.36]; P = 0.09). When the quartile containing the largest TLA and TLC values, respectively, were compared to the remaining cases, TLA remained significantly associated with fewer and TLC with more frequent shocks also after multivariate adjustment for clinical variables (HR, 0.59 [0.35–0.99], P = 0.044; and 1.64 [1.08–2.49], P = 0.021, respectively). Conclusions The size and shape of the T-wave loop calculated from pre-implantation 12-lead ECGs are associated with appropriate ICD shocks. PMID:28291831
Jin, Wanchun; Wachino, Jun-Ichi; Kimura, Kouji; Yamada, Keiko; Arakawa, Yoshichika
2015-05-01
Enterobacteriaceae clinical isolates showing amikacin resistance (MIC 64 to >256 mg/L) in the absence of 16S rRNA methyltransferase (MTase) genes were found. The aim of this study was to clarify the molecular mechanisms underlying amikacin resistance in Enterobacteriaceae clinical isolates that do not produce 16S rRNA MTases. PCR was performed to detect already-known amikacin resistance determinants. Cloning experiments and sequence analyses were performed to characterize unknown amikacin resistance determinants. Transfer of amikacin resistance determinants was performed by conjugation and transformation. The complete nucleotide sequence of the plasmids was determined by next-generation sequencing technology. Amikacin resistance enzymes were purified with a column chromatography system. The enzymatic function of the purified protein was investigated by thin-layer chromatography (TLC) and HPLC. Among the 14 isolates, 9 were found to carry already-known amikacin resistance determinants such as aac(6')-Ia and aac(6')-Ib. Genetic analyses revealed the presence of a new amikacin acetyltransferase gene, named aac(6')-Ian, located on a 169 829 bp transferable plasmid (p11663) of the Serratia marcescens strain NUBL-11663, one of the five strains negative for known aac(6') genes by PCR. Plasmid p11663 also carried a novel ESBL gene, named blaTLA-3. HPLC and TLC analyses demonstrated that AAC(6')-Ian catalysed the transfer of an acetyl group from acetyl coenzyme A onto an amine at the 6'-position of various aminoglycosides. We identified aac(6')-Ian as a novel amikacin resistance determinant together with a new ESBL gene, blaTLA-3, on a transferable plasmid of a S. marcescens clinical isolate. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Robroek, Suzan J W; Järvholm, Bengt; van der Beek, Allard J; Proper, Karin I; Wahlström, Jens; Burdorf, Alex
2017-09-01
The objectives of this study are to investigate the relation between obesity and labour force exit via diagnosis-specific disability benefits, and whether physical workload modifies this association. A longitudinal analysis was performed among 3 28 743 Swedish construction workers in the age of 15-65 years. Body weight and height were measured at a health examination and enriched with register information on disability benefits up to 37 years later. Diagnoses of disability benefits were categorised into cardiovascular diseases (CVDs), musculoskeletal diseases (MSDs), mental disorders and others. A job exposure matrix, based on self-reported lifting of heavy loads and working in bent forward or twisted position, was applied as a measure of physical workload. Cox proportional hazards regression analyses were performed, and the relative excess risk due to interaction (RERI) between obesity and physical workload was calculated. Obese construction workers were at increased risk of receiving disability benefits (HR 1.70, 95% CI 1.65 to 2.76), mainly through CVD (HR 2.30) and MSD (HR 1.71). Construction workers with a high physical workload were also more likely to receive a disability benefit (HR 2.28, 95% CI 2.21 to 2.34), particularly via MSD (HR 3.02). Obesity in combination with a higher physical workload increased the risk of disability benefits (RERI 0.28) more than the sum of the risks of obesity and higher physical workload, particularly for MSD (RERI 0.44). Obesity and a high physical workload are risk factors for disability benefit. Furthermore, these factors are synergistic risk factors for labour force exit via disability benefit through MSD. Comprehensive programmes that target health promotion to prevent obesity and ergonomic interventions to reduce physical workload are important to facilitate sustained employment. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Crew Integration & Automation Testbed and Robotic Follower Programs
2001-05-30
Evolving Technologies for Reduced Crew Operation” Vehicle Tech Demo #1 (VTT) Vehicle Tech Demo #2 ( CAT ATD) Two Man Transition Future Combat...Simulation Advanced Electronic Architecture Concept Vehicle Shown with Onboard Safety Driver Advanced Interfaces CAT ATD Exit Criteria...Provide 1000 Hz control loop for critical real-time tasks CAT Workload IPT Process and Product Schedule Crew Task List Task Timelines Workload Analysis
ERIC Educational Resources Information Center
Lindahl, Kristen Marie
2013-01-01
This study investigates the construct of Teacher Language Awareness (TLA) in a group of preservice mainstream K-12 teachers who are developing skills to work with English Language Learners (ELLs) in United States (US) public school contexts. Specifically, the study seeks to explore how preservice teachers' participation in directed university…
Small Shifts, Big Changes: Changing the Story for Students with Sensory Processing Sensitivity (SPS)
ERIC Educational Resources Information Center
Cater, Kaaryn
2016-01-01
It is my privilege to work as a tertiary learning advisor (TLA). Through my role I have had the opportunity to form unique relationships with students during individual consultations. This has enabled me to observe student behaviour, and the metacognitive strategies students use to negotiate the myriad challenges of tertiary study. I noticed…
Cross-Linguistic Influence in Third Language Perception: L2 and L3 Perception of Japanese Contrasts
ERIC Educational Resources Information Center
Onishi, Hiromi
2013-01-01
This dissertation examines the possible influence of language learners' second language (L2) on their perception of phonological contrasts in their third language (L3). Previous studies on Third Language Acquisition (TLA) suggest various factors as possible sources of cross-linguistic influence in the acquisition of an L3. This dissertation…
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This Technology Learning Activity (TLA) on exploring diagnostic care careers for Grade 9 is designed for use in eight class periods. It gives students experience in using standard health care equipment to perform basic diagnostic procedures. This teacher's edition begins with an overview of technology education. The second section describes…
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This Technology Learning Activity (TLA) for exploring therapeutic care careers is designed for use in eight class periods. It exposes students to the different types of therapeutic care and helps them understand how they can be used to treat and heal. This teacher's edition begins with an overview of technology education. The second section…
NASA Astrophysics Data System (ADS)
Rolland, J.-F.; Filali, M.; Bodeveixm, J.-P.; Chemouil, D.; Thomas, D.; Rossignol, A.
2008-08-01
In this paper we study the mode concept in AADL. First we present briefly this language and we define the subset that we use. Then, we propose an abstract TLA+ specification of the mode transition. Then, we discuss how the mode concepts proposed AADL could be related to this abstraction. We also present different issues related to the mode transition.
Teaching, Learning and Assessing HRD: Findings from a BMAF/UFHRD Research Project
ERIC Educational Resources Information Center
Sambrook, Sally; Stewart, Jim
2010-01-01
Purpose: This paper seeks to analyse and explore the results of a research project, which aimed to identify recent and current research on TLA within HRD programmes. From that base the project also intended to identify areas for future research and a basis for establishing a Special Interest Group. Design/methodology/approach: A comprehensive…
Radüntz, Thea
2017-01-01
One goal of advanced information and communication technology is to simplify work. However, there is growing consensus regarding the negative consequences of inappropriate workload on employee's health and the safety of persons. In order to develop a method for continuous mental workload monitoring, we implemented a task battery consisting of cognitive tasks with diverse levels of complexity and difficulty. We conducted experiments and registered the electroencephalogram (EEG), performance data, and the NASA-TLX questionnaire from 54 people. Analysis of the EEG spectra demonstrates an increase of the frontal theta band power and a decrease of the parietal alpha band power, both under increasing task difficulty level. Based on these findings we implemented a new method for monitoring mental workload, the so-called Dual Frequency Head Maps (DFHM) that are classified by support vectors machines (SVMs) in three different workload levels. The results are in accordance with the expected difficulty levels arising from the requirements of the tasks on the executive functions. Furthermore, this article includes an empirical validation of the new method on a secondary subset with new subjects and one additional new task without any adjustment of the classifiers. Hence, the main advantage of the proposed method compared with the existing solutions is that it provides an automatic, continuous classification of the mental workload state without any need for retraining the classifier—neither for new subjects nor for new tasks. The continuous workload monitoring can help ensure good working conditions, maintain a good level of performance, and simultaneously preserve a good state of health. PMID:29276490
[Variability in nursing workload within Swiss Diagnosis Related Groups].
Baumberger, Dieter; Bürgin, Reto; Bartholomeyczik, Sabine
2014-04-01
Nursing care inputs represent one of the major cost components in the Swiss Diagnosis Related Group (DRG) structure. High and low nursing workloads in individual cases are supposed to balance out via the DRG group. Research results indicating possible problems in this area cannot be reliably extrapolated to SwissDRG. An analysis of nursing workload figures with DRG indicators was carried out in order to decide whether there is a need to develop SwissDRG classification criteria that are specific to nursing care. The case groups were determined with SwissDRG 0.1, and nursing workload with LEP Nursing 2. Robust statistical methods were used. The evaluation of classification accuracy was carried out with R2 as the measurement of variance reduction and the coefficient of homogeneity (CH). To ensure reliable conclusions, statistical tests with bootstrapping methods were performed. The sample included 213 groups with a total of 73930 cases from ten hospitals. The DRG classification was seen to have limited explanatory power for variability in nursing workload inputs, both for all cases (R2 = 0.16) and for inliers (R2 = 0.32). Nursing workload homogeneity was statistically significant unsatisfactory (CH < 0.67) in 123 groups, including 24 groups in which it was significant defective (CH < 0.60). Therefore, there is a high risk of high and low nursing workloads not balancing out in these groups, and, as a result, of financial resources being wrongly allocated. The development of nursing-care-specific SwissDRG classification criteria for improved homogeneity and variance reduction is therefore indicated.
The Effects of Workload Transitions in a Multitasking Environment
2016-09-13
completed the NASA Task Load Index to assess subjective workload, and the shortened Dundee Stress State Questionnaire to measure subjective task-related...and the analysis of both the NASA Task Load Index and of the shortened Dundee State Questionnaire did not reveal any significant differences related...Electroencepholography (EEG), NASA Task Load Index ( NASA TLX), Dundee Stress State Questionnaire (DSSQ), Hysteresis 16. SECURITY CLASSIFICATION OF
Practical guidelines for workload assessment
NASA Technical Reports Server (NTRS)
Tattersall, Andrew J.
1994-01-01
The practical problems that might be encountered in carrying out workload evaluations in work settings have been outlined. Different approaches have been distinguished that may determine the type of research design used and provide assistance in the difficult choice between workload assessment techniques. One approach to workload assessment is to examine the short-term consequences of combining various tasks. Theoretical models of attention allocation will underpin specific studies of interference and the consequences of task demand and task conflict for performance. A further approach with a different temporal orientation may lead us to a better understanding of the relationships between work demands and strain through the analysis of individual differences in cognitive control processes. The application of these processes may depend on individual differences in long term styles and short term strategies, but may be used to prevent decrements in work performance under difficult conditions. However, control may attract costs as well as benefits in terms of changes in effective state and physiological activity. Thus, strain associated with work demands may only be measurable in the form of tradeoffs between performance and other domains of individual activity. The methodological implications are to identify patterns of adjustment to workload variations using repeated measures and longitudinal sampling of performance as well as subjective and physiological measures. Possible enhancements to workplace design must take into account these human factors considerations of workload in order to avoid potential decrements in individual performance and associated organizational problems.
Lilje, Stina C; Skillgate, Eva; Anderberg, Peter; Berglund, Johan
2015-07-01
Pain is one of the most frequent reasons for seeking health care, and is thus a public health problem. Although there is a progressive increase in pain and impaired physical function with age, few studies are performed on older adults. The aim of this study was to investigate if there are associations between musculoskeletal pain interfering with normal life in older adults and physical and psychosocial workloads through life. The association of heavy physical workload and negative psychosocial workload and musculoskeletal pain interfering with normal life (SF 12) was analyzed by multiple logistic regression. The model was adjusted for eight background covariates: age, gender, growing-up environment, educational level, if living alone or not, obesity, smoking, and leisure physical activity. Negative psychosocial and heavy physical workloads were independently associated with musculoskeletal pain interfering with normal life (adjusted OR: 4.44, 95% CI: 2.84-6.92), and (adjusted OR: 1.88, 95% CI: 1.20-2.93), respectively. The background covariates female gender and higher education were also associated with musculoskeletal pain interfering with normal life, and physical leisure activity was inversely associated. The findings suggest that negative psychosocial and heavy physical workloads are strongly associated with musculoskeletal pain interfering with normal life in older adults. © 2015 the Nordic Societies of Public Health.
Analysis of Mental Workload in Online Shopping: Are Augmented and Virtual Reality Consistent?
Zhao, Xiaojun; Shi, Changxiu; You, Xuqun; Zong, Chenming
2017-01-01
A market research company (Nielsen) reported that consumers in the Asia-Pacific region have become the most active group in online shopping. Focusing on augmented reality (AR), which is one of three major techniques used to change the method of shopping in the future, this study used a mixed design to discuss the influences of the method of online shopping, user gender, cognitive style, product value, and sensory channel on mental workload in virtual reality (VR) and AR situations. The results showed that males' mental workloads were significantly higher than females'. For males, high-value products' mental workload was significantly higher than that of low-value products. In the VR situation, the visual mental workload of field-independent and field-dependent consumers showed a significant difference, but the difference was reduced under audio-visual conditions. In the AR situation, the visual mental workload of field-independent and field-dependent consumers showed a significant difference, but the difference increased under audio-visual conditions. This study provided a psychological study of online shopping with AR and VR technology with applications in the future. Based on the perspective of embodied cognition, AR online shopping may be potential focus of research and market application. For the future design of online shopping platforms and the updating of user experience, this study provides a reference.
Analysis of Mental Workload in Online Shopping: Are Augmented and Virtual Reality Consistent?
Zhao, Xiaojun; Shi, Changxiu; You, Xuqun; Zong, Chenming
2017-01-01
A market research company (Nielsen) reported that consumers in the Asia-Pacific region have become the most active group in online shopping. Focusing on augmented reality (AR), which is one of three major techniques used to change the method of shopping in the future, this study used a mixed design to discuss the influences of the method of online shopping, user gender, cognitive style, product value, and sensory channel on mental workload in virtual reality (VR) and AR situations. The results showed that males’ mental workloads were significantly higher than females’. For males, high-value products’ mental workload was significantly higher than that of low-value products. In the VR situation, the visual mental workload of field-independent and field-dependent consumers showed a significant difference, but the difference was reduced under audio–visual conditions. In the AR situation, the visual mental workload of field-independent and field-dependent consumers showed a significant difference, but the difference increased under audio–visual conditions. This study provided a psychological study of online shopping with AR and VR technology with applications in the future. Based on the perspective of embodied cognition, AR online shopping may be potential focus of research and market application. For the future design of online shopping platforms and the updating of user experience, this study provides a reference. PMID:28184207
Development of techniques for measuring pilot workload
NASA Technical Reports Server (NTRS)
Spyker, D. A.; Stackhouse, S. P.; Khalafalla, A. S.; Mclane, R. C.
1971-01-01
An objective method of assessing information workload based on physiological measurements was developed. Information workload, or reserve capacity, was measured using a visual discrimination secondary task and subjective rating of task difficulty. The primary task was two axis (pitch and roll) tracking, and the independent variables in this study were aircraft pitch dynamics and wind gust disturbances. The study was structured to provide: (1) a sensitive, nonloading measure of reserve capacity, and (2) an unencumbering reliable measurement of the psychophysiological state. From these, a measured workload index (MWI) and physiological workload index (PWI) were extracted. An important measure of the success of this study was the degree to which the MWI and PWI agreed across the 243 randomly-presented, four-minute trials (9 subjects X 9 tasks X 3 replications). The electrophysiological data collected included vectorcardiogaram, respiration, electromyogram, skin impedance, and electroencephalogram. Special computer programs were created for the analysis of each physiological variable. The digital data base then consisted of 82 physiological features for each of the 243 trials. A prediction of workload based on physiological observations was formulated as a simultaneous least-squares prediction problem. A best subset of 10 features was chosen to predict the three measures of reserve capacity. The cannonical correlation coefficient was .754 with a chi squared value of 91.3 which allows rejection of the null hypothesis with p of .995.
Hannula, Manne; Huttunen, Kerttu; Koskelo, Jukka; Laitinen, Tomi; Leino, Tuomo
2008-01-01
In this study, the performances of artificial neural network (ANN) analysis and multilinear regression (MLR) model-based estimation of heart rate were compared in an evaluation of individual cognitive workload. The data comprised electrocardiography (ECG) measurements and an evaluation of cognitive load that induces psychophysiological stress (PPS), collected from 14 interceptor fighter pilots during complex simulated F/A-18 Hornet air battles. In our data, the mean absolute error of the ANN estimate was 11.4 as a visual analog scale score, being 13-23% better than the mean absolute error of the MLR model in the estimation of cognitive workload.
Mental workload while driving: effects on visual search, discrimination, and decision making.
Recarte, Miguel A; Nunes, Luis M
2003-06-01
The effects of mental workload on visual search and decision making were studied in real traffic conditions with 12 participants who drove an instrumented car. Mental workload was manipulated by having participants perform several mental tasks while driving. A simultaneous visual-detection and discrimination test was used as performance criteria. Mental tasks produced spatial gaze concentration and visual-detection impairment, although no tunnel vision occurred. According to ocular behavior analysis, this impairment was due to late detection and poor identification more than to response selection. Verbal acquisition tasks were innocuous compared with production tasks, and complex conversations, whether by phone or with a passenger, are dangerous for road safety.
Contribution of mental workload to job stress in industrial workers.
González-Muñoz, Elvia Luz; Gutiérrez-Martínez, Rodolfo E
2007-01-01
This study's central objective is to determine how several individual, organizational and ergonomic factors influence the relationship between job stress and mental workload for workers in an electronics company. A cross-sectional study was made as a test of hypotheses regarding that relationship. The sample is composed of 95 workers, of both sexes, from the electronics industry in the metropolitan zone of Guadalajara, Jalisco, Mexico. Ergonomic conditions were evaluated with the Ergonomic Evaluation List, stress was evaluated by administering the SWS-Survey to groups of subjects, and mental workload was evaluated with the NASA-TLX Workload Index. Using Cochran's and Mantel-Haenzsel statistics, the odds ratio for each of the independent variables was {e}stimated as a risk factor for job stress, and analysis was later conducted by means of logistic regression for those risks found to be significant. Of the 95 worker participants, 26.3% presented a high level of job stress and 17.9% of the workers were found to present high levels of mental workload. The results show that working hours, mental demand, temporal demand, and frustration when faced with a given task may be considered risk factors for job stress.
Filter bank common spatial patterns in mental workload estimation.
Arvaneh, Mahnaz; Umilta, Alberto; Robertson, Ian H
2015-01-01
EEG-based workload estimation technology provides a real time means of assessing mental workload. Such technology can effectively enhance the performance of the human-machine interaction and the learning process. When designing workload estimation algorithms, a crucial signal processing component is the feature extraction step. Despite several studies on this field, the spatial properties of the EEG signals were mostly neglected. Since EEG inherently has a poor spacial resolution, features extracted individually from each EEG channel may not be sufficiently efficient. This problem becomes more pronounced when we use low-cost but convenient EEG sensors with limited stability which is the case in practical scenarios. To address this issue, in this paper, we introduce a filter bank common spatial patterns algorithm combined with a feature selection method to extract spatio-spectral features discriminating different mental workload levels. To evaluate the proposed algorithm, we carry out a comparative analysis between two representative types of working memory tasks using data recorded from an Emotiv EPOC headset which is a mobile low-cost EEG recording device. The experimental results showed that the proposed spatial filtering algorithm outperformed the state-of-the algorithms in terms of the classification accuracy.
ERIC Educational Resources Information Center
Kanbayashi, Toshiyuki
2016-01-01
In recent years, teachers' increased workloads have become an issue for policy, and have been multiply pointed out, deriving as they do from peripheral duties such as paperwork, in academic research as well. However, these mentions have not been based on sufficiently solid proof. Here, this paper compares teacher working hours surveys extant from…
Evolution of the ATLAS PanDA workload management system for exascale computational science
NASA Astrophysics Data System (ADS)
Maeno, T.; De, K.; Klimentov, A.; Nilsson, P.; Oleynik, D.; Panitkin, S.; Petrosyan, A.; Schovancova, J.; Vaniachine, A.; Wenaus, T.; Yu, D.; Atlas Collaboration
2014-06-01
An important foundation underlying the impressive success of data processing and analysis in the ATLAS experiment [1] at the LHC [2] is the Production and Distributed Analysis (PanDA) workload management system [3]. PanDA was designed specifically for ATLAS and proved to be highly successful in meeting all the distributed computing needs of the experiment. However, the core design of PanDA is not experiment specific. The PanDA workload management system is capable of meeting the needs of other data intensive scientific applications. Alpha-Magnetic Spectrometer [4], an astro-particle experiment on the International Space Station, and the Compact Muon Solenoid [5], an LHC experiment, have successfully evaluated PanDA and are pursuing its adoption. In this paper, a description of the new program of work to develop a generic version of PanDA will be given, as well as the progress in extending PanDA's capabilities to support supercomputers and clouds and to leverage intelligent networking. PanDA has demonstrated at a very large scale the value of automated dynamic brokering of diverse workloads across distributed computing resources. The next generation of PanDA will allow other data-intensive sciences and a wider exascale community employing a variety of computing platforms to benefit from ATLAS' experience and proven tools.
NASA Astrophysics Data System (ADS)
Ruliati, L. P.; Adiputra, N.; Sutjana, I. D. P.; Sutajaya, I. M.
2017-11-01
Rice mill is one of the businesses in informal sector. From the rice milling process, ergonomic problems arise when employees work with bent position that done repeatedly to lift grain sacks to be transferred to peeler machine. This situation will affect the comfort of work, thus increasing the workload, muscle tension, and fatigue. The consequence will certainly affect the health and productivity of workers. In this study introduces ergo Tri Hita Karana (ergo THK) as an ergonomics intervention model which solves ergonomics problems of the cultural aspects of THK. The study aim is to determine the modification of working conditions based Ergo THK to reduce workload, muscle tension and fatigue. This research uses Randomized Pretest and Posttest Control Group Design experimental design. The subjects were 30 male rice mill workers with an age range of 16 until 56 years, and then divided into 15 subjects in the control group and 15 subjects in the treatment group. The results showed that the average posttest workloads in the control group are 136.950 more less 0.297 and in the treatment group are 107.60 more less 0.396. Significance analysis showed that after the two groups done their activities, the average workload significantly different p less than 0.005. The amount of reduction in the workload between the two groups was 21.43 percent. In muscle tension posttest showed that the mean score of the muscle tension in the control group was 62.67 more less 7.31 and the treatment group was 20.96 more less 2.96. Significance analysis showed that both groups mean muscle-tension results were significantly different p less than 0.005. The amount of reduction in tension between the control group and the treatment group while working was 66.55 percent. At fatigue posttest showed that the mean score of fatigue in the control group was 76.40 more less 13.51 and the treatment group was 55.53 more less 9.51. Significant analysis showed that the mean fatigue of both groups significantly different p less than 0.005. The amount of reduction in fatigue between the control group and the treatment group while working was 27.31 percent. From this study it can be concluded that the modification of the working conditions based on Ergo THK can reduce the workload by 21.43 percent, muscle tension by 66.55 percent and fatigue by 27.31 percent.
Hobbs, F D Richard; Bankhead, Clare; Mukhtar, Toqir; Stevens, Sarah; Perera-Salazar, Rafael; Holt, Tim; Salisbury, Chris
2016-06-04
Primary care is the main source of health care in many health systems, including the UK National Health Service (NHS), but few objective data exist for the volume and nature of primary care activity. With rising concerns that NHS primary care workload has increased substantially, we aimed to assess the direct clinical workload of general practitioners (GPs) and practice nurses in primary care in the UK. We did a retrospective analysis of GP and nurse consultations of non-temporary patients registered at 398 English general practices between April, 2007, and March, 2014. We used data from electronic health records routinely entered in the Clinical Practice Research Datalink, and linked CPRD data to national datasets. Trends in age-standardised and sex-standardised consultation rates were modelled with joinpoint regression analysis. The dataset comprised 101,818,352 consultations and 20,626,297 person-years of observation. The crude annual consultation rate per person increased by 10·51%, from 4·67 in 2007-08, to 5·16 in 2013-14. Consultation rates were highest in infants (age 0-4 years) and elderly people (≥85 years), and were higher for female patients than for male patients of all ages. The greatest increases in age-standardised and sex-standardised rates were in GPs, with a rise of 12·36% per 10,000 person-years, compared with 0·9% for practice nurses. GP telephone consultation rates doubled, compared with a 5·20% rise in surgery consultations, which accounted for 90% of all consultations. The mean duration of GP surgery consultations increased by 6·7%, from 8·65 min (95% CI 8·64-8·65) to 9·22 min (9·22-9·23), and overall workload increased by 16%. Our findings show a substantial increase in practice consultation rates, average consultation duration, and total patient-facing clinical workload in English general practice. These results suggest that English primary care as currently delivered could be reaching saturation point. Notably, our data only explore direct clinical workload and not indirect activities and professional duties, which have probably also increased. This and additional research questions, including the outcomes of workload changes on other sectors of health care, need urgent answers for primary care provision internationally. Department of Health Policy Research Programme. Copyright © 2016 Hobbs et al. Open Access article distributed under the terms of CC BY. Published by Elsevier Ltd.. All rights reserved.
Autotasked Performance in the NAS Workload: A Statistical Analysis
NASA Technical Reports Server (NTRS)
Carter, R. L.; Stockdale, I. E.; Kutler, Paul (Technical Monitor)
1998-01-01
A statistical analysis of the workload performance of a production quality FORTRAN code for five different Cray Y-MP hardware and system software configurations is performed. The analysis was based on an experimental procedure that was designed to minimize correlations between the number of requested CPUs and the time of day the runs were initiated. Observed autotasking over heads were significantly larger for the set of jobs that requested the maximum number of CPUs. Speedups for UNICOS 6 releases show consistent wall clock speedups in the workload of around 2. which is quite good. The observed speed ups were very similar for the set of jobs that requested 8 CPUs and the set that requested 4 CPUs. The original NAS algorithm for determining charges to the user discourages autotasking in the workload. A new charging algorithm to be applied to jobs run in the NQS multitasking queues also discourages NAS users from using auto tasking. The new algorithm favors jobs requesting 8 CPUs over those that request less, although the jobs requesting 8 CPUs experienced significantly higher over head and presumably degraded system throughput. A charging algorithm is presented that has the following desirable characteristics when applied to the data: higher overhead jobs requesting 8 CPUs are penalized when compared to moderate overhead jobs requesting 4 CPUs, thereby providing a charging incentive to NAS users to use autotasking in a manner that provides them with significantly improved turnaround while also maintaining system throughput.
Influence of patient and provider factors on the workload of on-call physicians
Hsu, Nin-Chieh; Huang, Chun-Che; Jerng, Jih-Shuin; Hsu, Chia-Hao; Yang, Ming-Chin; Chang, Ray-E; Ko, Wen-Je; Yu, Chong-Jen
2016-01-01
Abstract Factors associated with the physician workload are scarcely reported. The study aims to investigate the associated factors of on-call physician workload based on a published conceptual framework. The study was conducted in a general internal medicine unit of National Taiwan University Hospital. On-call physician workloads were recorded on a shift basis from 1198 hospitalized patients between May 2010 and April 2011. The proxy of on-call workloads included night calls, bedside evaluation/management (E/M), and performing clinical procedures in a shift. Multivariable logistic and negative binomial regression models were used to determine the factors associated with the workloads of on-call physicians. During the study period, 378 (31.6%) of patients had night calls with related workloads. Multivariate analysis showed that the number of patients with unstable conditions in a shift (odds ratio [OR] 1.89 and 1.66, respectively) and the intensive care unit (ICU) training of the nurse leader (OR 2.87 and 3.08, respectively) resulted in higher likelihood of night calls to and bedside E/M visits by the on-call physician. However, ICU training of nurses (OR = 0.37, 95% confidence interval: 0.16–0.86) decreased the demand of performing clinical procedures by the on-call physician. Moreover, number of patients with unstable conditions (risk ratio [RR] 1.52 and 1.55, respectively) had significantly increased the number of night calls and bedside E/M by on-call physicians by around 50%. Nurses with N1 level (RR 2.16 and 2.71, respectively) were more likely to place night calls and facilitate bedside E/M by the on-call physician compared to nurses with N0 level. In addition, the nurse leaders with ICU training (RR 1.72 and 3.07, respectively) had significant increases in night calls and bedside E/M by the on-call physician compared to those without ICU training. On-call physician workload is associated with patient factors and the training of nurses. Number of unstable patients in a shift may be considered in predicting workload. The training of nurses may improve patient safety and decrease demand for clinical procedure. PMID:27583910
Hsu, Nin-Chieh; Huang, Chun-Che; Jerng, Jih-Shuin; Hsu, Chia-Hao; Yang, Ming-Chin; Chang, Ray-E; Ko, Wen-Je; Yu, Chong-Jen
2016-08-01
Factors associated with the physician workload are scarcely reported. The study aims to investigate the associated factors of on-call physician workload based on a published conceptual framework.The study was conducted in a general internal medicine unit of National Taiwan University Hospital. On-call physician workloads were recorded on a shift basis from 1198 hospitalized patients between May 2010 and April 2011. The proxy of on-call workloads included night calls, bedside evaluation/management (E/M), and performing clinical procedures in a shift. Multivariable logistic and negative binomial regression models were used to determine the factors associated with the workloads of on-call physicians.During the study period, 378 (31.6%) of patients had night calls with related workloads. Multivariate analysis showed that the number of patients with unstable conditions in a shift (odds ratio [OR] 1.89 and 1.66, respectively) and the intensive care unit (ICU) training of the nurse leader (OR 2.87 and 3.08, respectively) resulted in higher likelihood of night calls to and bedside E/M visits by the on-call physician. However, ICU training of nurses (OR = 0.37, 95% confidence interval: 0.16-0.86) decreased the demand of performing clinical procedures by the on-call physician. Moreover, number of patients with unstable conditions (risk ratio [RR] 1.52 and 1.55, respectively) had significantly increased the number of night calls and bedside E/M by on-call physicians by around 50%. Nurses with N1 level (RR 2.16 and 2.71, respectively) were more likely to place night calls and facilitate bedside E/M by the on-call physician compared to nurses with N0 level. In addition, the nurse leaders with ICU training (RR 1.72 and 3.07, respectively) had significant increases in night calls and bedside E/M by the on-call physician compared to those without ICU training.On-call physician workload is associated with patient factors and the training of nurses. Number of unstable patients in a shift may be considered in predicting workload. The training of nurses may improve patient safety and decrease demand for clinical procedure.
NASA Technical Reports Server (NTRS)
Hemingway, J. C.
1984-01-01
The objective was to determine whether the Sternberg item-recognition task, employed as a secondary task measure of spare mental capacity for flight handling qualities (FHQ) simulation research, could help to differentiate between different flight-control conditions. FHQ evaluations were conducted on the Vertical Motion Simulator at Ames Research Center to investigate different primary flight-control configurations, and selected stability and control augmentation levels for helicopters engaged in low-level flight regimes. The Sternberg task was superimposed upon the primary flight-control task in a balanced experimental design. The results of parametric statistical analysis of Sternberg secondary task data failed to support the continued use of this task as a measure of pilot workload. In addition to the secondary task, subjects provided Cooper-Harper pilot ratings (CHPR) and responded to workload questionnaire. The CHPR data also failed to provide reliable statistical discrimination between FHQ treatment conditions; some insight into the behavior of the secondary task was gained from the workload questionnaire data.
Heavy physician workloads: impact on physician attitudes and outcomes.
Williams, Eric S; Rondeau, Kent V; Xiao, Qian; Francescutti, Louis H
2007-11-01
The intensity of physician workload has been increasing with the well-documented changes in the financing, organization and delivery of care. It is possible that these stressors have reached a point where they pose a serious policy issue for the entire healthcare system through their diminution of physician's ability to effectively interact with patients as they are burned out, stressed and dissatisfied. This policy question is framed in a conceptual model linking workloads with five key outcomes (patient care quality, individual performance, absenteeism, turnover and organizational performance) mediated by physician stress and satisfaction. This model showed a good fit to the data in a structural equation analysis. Ten of the 12 hypothesized pathways between variables were significant and supported the mediating role of stress and satisfaction. These results suggest that workloads, stress and satisfaction have significant and material impacts on patient care quality, individual performance, absenteeism, turnover and organizational performance. Implications of these results and directions for future research are discussed.
Driver behaviour with adaptive cruise control.
Stanton, Neville A; Young, Mark S
2005-08-15
This paper reports on the evaluation of adaptive cruise control (ACC) from a psychological perspective. It was anticipated that ACC would have an effect upon the psychology of driving, i.e. make the driver feel like they have less control, reduce the level of trust in the vehicle, make drivers less situationally aware, but workload might be reduced and driving might be less stressful. Drivers were asked to drive in a driving simulator under manual and ACC conditions. Analysis of variance techniques were used to determine the effects of workload (i.e. amount of traffic) and feedback (i.e. degree of information from the ACC system) on the psychological variables measured (i.e. locus of control, trust, workload, stress, mental models and situation awareness). The results showed that: locus of control and trust were unaffected by ACC, whereas situation awareness, workload and stress were reduced by ACC. Ways of improving situation awareness could include cues to help the driver predict vehicle trajectory and identify conflicts.
The Sternberg Task as a Workload Metric in Flight Handling Qualities Research
NASA Technical Reports Server (NTRS)
Hemingway, J. C.
1984-01-01
The objective of this research was to determine whether the Sternberg item-recognition task, employed as a secondary task measure of spare mental capacity for flight handling qualities (FHQ) simulation research, could help to differentiate between different flight-control conditions. FHQ evaluations were conducted on the Vertical Motion Simulator at Ames Research Center to investigate different primary flight-control configurations, and selected stability and control augmentation levels for helicopers engaged in low-level flight regimes. The Sternberg task was superimposed upon the primary flight-control task in a balanced experimental design. The results of parametric statistical analysis of Sternberg secondary task data failed to support the continued use of this task as a measure of pilot workload. In addition to the secondary task, subjects provided Cooper-Harper pilot ratings (CHPR) and responded to a workload questionnaire. The CHPR data also failed to provide reliable statistical discrimination between FHQ treatment conditions; some insight into the behavior of the secondary task was gained from the workload questionnaire data.
Assessment of Automated Analyses of Cell Migration on Flat and Nanostructured Surfaces
Grădinaru, Cristian; Łopacińska, Joanna M.; Huth, Johannes; Kestler, Hans A.; Flyvbjerg, Henrik; Mølhave, Kristian
2012-01-01
Motility studies of cells often rely on computer software that analyzes time-lapse recorded movies and establishes cell trajectories fully automatically. This raises the question of reproducibility of results, since different programs could yield significantly different results of such automated analysis. The fact that the segmentation routines of such programs are often challenged by nanostructured surfaces makes the question more pertinent. Here we illustrate how it is possible to track cells on bright field microscopy images with image analysis routines implemented in an open-source cell tracking program, PACT (Program for Automated Cell Tracking). We compare the automated motility analysis of three cell tracking programs, PACT, Autozell, and TLA, using the same movies as input for all three programs. We find that different programs track overlapping, but different subsets of cells due to different segmentation methods. Unfortunately, population averages based on such different cell populations, differ significantly in some cases. Thus, results obtained with one software package are not necessarily reproducible by other software. PMID:24688640
The Cyprus Game: Crossing the Boundaries in a Divided Island
ERIC Educational Resources Information Center
Shaw, Matthew
2014-01-01
In this article I consider the place of a school in Cyprus that admits students from both sides of the Green Line and the role sport is meant to play in bringing students from diverse backgrounds together. One of the island's elite schools, The Lefkos Academy (TLA), is one of the few places where Greek Cypriots and Turkish Cypriots gather together…
2007-11-16
Experiment currents and analyzed the mean and eddy kinetic energies of (AC) together with the NATO) Undersea Research Centre the Adriatic using a...1141. .,uppoted by tte Office of Nav al Research as part of thc research prograttis Orlic, M.. NI. 6a6i, atid P.i F. tLa Violette (1992). The eurreitts
Deictics and the Construction of Mathematics and Science Knowledge in the Secondary School Classroom
ERIC Educational Resources Information Center
Hansen-Thomas, Holly; Langman, Juliet
2017-01-01
Taking a Teacher Language Awareness (TLA) perspective, this paper examines how the concept of deixis is employed in oral discourse in two secondary science and mathematics classes in the southwestern part of the US. Drawing on audio and videotaped data from two classrooms, we examine how verbal deixis, or words and phrases that cannot be fully…
ERIC Educational Resources Information Center
Kujalowicz, Agnieszka; Zajdler, Ewa
2009-01-01
Many offline studies on third language acquisition suggest strong connections between speakers' L3 and L2 rather than between their L3 and L1, especially if the foreign languages are typologically related (Cenoz, Hufeisen, & Jessner, 2001; Singleton, 2001). However, a recent online study investigating trilingual processing did not provide evidence…
Metrology conditions for thin layer activation in wear and corrosion studies
NASA Astrophysics Data System (ADS)
Lacroix, O.; Sauvage, T.; Blondiaux, G.; Racolta, P. M.; Popa-Simil, L.; Alexandreanu, B.
1996-02-01
Thin Layer Activation (TLA) is an ion beam technique. This method consists of an accelerated ion bombardment of the surface of interest of a machine part subjected to wear. Radioactive tracers are created by nuclear reactions in a well defined volume of material. Loss of material owing to wear, corrosion or abrasion phenomena is characterized by monitoring the resulting changes in radioactivity. For the industrial application of this method, special attention has been paid during irradiation to the range of activated thickness, yields and activation homogeneity and to on-line radioactivity measurements. There are two basic methods for measuring the material loss by TLA technique. One of them is based on remanant radioactivity measurements using a previously obtained calibration curve. The second is based on measuring the increasing radioactivity in the lubricant due to suspended wear particles. In this paper, we have chosen to present some calibration curves for both proton and deuteron irradiation of Fe, Cr, Cu, Ti and Ni samples. Thickness ranges are indicated and intrinsic error checking and calculational procedures are also presented. The article ends with a review of some typical experiments involving running-in programme optimization and lubricants certifying procedures.
Alcantar-Curiel, Dolores; Tinoco, Juan Carlos; Gayosso, Catalina; Carlos, Angeles; Daza, Carlos; Perez-Prado, Maria C; Salcido, Lorena; Santos, Jose I; Alpuche-Aranda, Celia M
2004-04-15
We describe the prevalence and molecular characteristics of extended-spectrum beta -lactamase (ESBL)-producing Klebsiella pneumoniae causing nosocomial bacteremia and urinary tract infections in a Mexican general hospital. We analyzed 82 episodes of bacteremia (approximately 60% of episodes) and urinary tract infection (approximately 40% of episodes) due to K. pneumoniae during a 23-month surveillance period. The neonatal intensive care unit accounted for 49% of all episodes. All strains were imipenem susceptible; 62.2% of the strains were resistant to ceftazidime, cefotaxime, and aztreonam; 69.5% were resistant to amikacin; 58.5% were resistant to gentamicin; and 7.3% were resistant to ciprofloxacin. All strains were associated with 28 pulsed-field gel electrophoresis patterns, and dissemination of 2 ceftazidime-resistant clones produced 44% of the cases. The ESBL phenotype in these clones was transferred by identical or highly related megaplasmids. The ESBL activity corresponded to SHV-5 and TLA-1. Cross-transmission of 2 ceftazidime-resistant clones and the horizontal spread of identical or highly related megaplasmids explain the high prevalence of ESBL phenotype in these infections.
Corrosion monitoring on a large steel pressure vessel by thin-layer activation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wallace, G.; Boulton, L.H.; Hodder, D.
1989-12-01
Thin-layer activation (TLA) is a technique in which a surface is irradiated by a nuclear accelerator and thereby labeled with an accurate depth profile of low-level radioactivity. By monitoring this activity it is possible to calculate how much of that surface has been removed by corrosion. As the radioactivity is marked by the emission of penetrating gamma rays, it is possible to monitor this corrosion remotely through several centimeters of steel. This technique has been used to monitor erosion-corrosion occurring on the inner carbon steel wall of a continuous Kraft pulp digester at a paper mill. Representative coupons of themore » same steel as the digester wall were irradiated and fixed to the walls in the liquor extraction zone during a maintenance shutdown. The loss of metal over the six months was measured by external monitoring of gamma radiation through the vessel wall, and converted to a corrosion rate. Subsequent weight-loss measurements and comparison with ultrasonic thickness measurements established that the corrosion rate measured gave accurate results over a much shorter time scale. TLA thus enables current, rather than historical corrosion rates to be measured in a large steel pressure vessel.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meshkov, N. K.
1998-08-27
Titanium dioxide (TiO{sub 2}) colloidal particles ({approximately}45{angstrom}) whose surfaces were modified with chelating agents for photocatalytic removal of heavy-metal ions and their subsequent reduction to metallic form were investigated. Experiments were performed on nanoparticle TiO{sub 2} colloids derivatized with bidentate and tridentate ligands (thiolactic acid [TLA], cysteine, and alanine [ALA]) in batch mode in a photoreactor with 254nm light. We used catalysts designed and synthesized for selective and efficient removal of Pb and Cu with and without added hole scavenger (methanol). Parallel experiments also have been carried out in the dark to study metal ion adsorption properties. Solutions have beenmore » filtered to remove TiO{sub 2}, and metal particulates. Both the native solution and the metal deposited on the nanocrystalline TiO{sub 2} particles were analyzed. Results demonstrate that for the case of lead, the most effective TiO{sub 2} surface modifier was TLA (>99% Pb(II) removed from solution). Experiments performed to study Cn removal using TiO{sub 2} colloids modified with alanine showed that copper ions were effectively removed and reduced to metallic form in the presence of methanol.« less
Saxena, R C; Biswal, Jayashree; Pant, H J; Samantray, J S; Sharma, S C; Gupta, A K; Ray, S S
2018-05-01
Acidic crude oil transportation and processing in petroleum refining and petrochemical operations cause corrosion in the pipelines and associated components. Corrosion monitoring is invariably required to test and prove operational reliability. Thin Layer Activation (TLA) technique is a nuclear technique used for measurement of corrosion and erosion of materials. The technique involves irradiation of material with high energy ion beam from an accelerator and measurement of loss of radioactivity after the material is subjected to corrosive environment. In the present study, TLA technique has been used to monitor corrosion of carbon steel (CS) in crude oil environment at high temperature. Different CS coupons were irradiated with a 13 MeV proton beam to produce Cobalt-56 radioisotope on the surface of the coupons. The corrosion studies were carried out by subjecting the irradiated coupons to a corrosive environment, i.e, uninhibited straight run gas oil (SRGO) containing known amount of naphthenic acid (NA) at high temperature. The effects of different parameters, such as, concentration of NA, temperature and fluid velocity (rpm) on corrosion behaviour of CS were studied. Copyright © 2018 Elsevier Ltd. All rights reserved.
Automated clustering-based workload characterization
NASA Technical Reports Server (NTRS)
Pentakalos, Odysseas I.; Menasce, Daniel A.; Yesha, Yelena
1996-01-01
The demands placed on the mass storage systems at various federal agencies and national laboratories are continuously increasing in intensity. This forces system managers to constantly monitor the system, evaluate the demand placed on it, and tune it appropriately using either heuristics based on experience or analytic models. Performance models require an accurate workload characterization. This can be a laborious and time consuming process. It became evident from our experience that a tool is necessary to automate the workload characterization process. This paper presents the design and discusses the implementation of a tool for workload characterization of mass storage systems. The main features of the tool discussed here are: (1)Automatic support for peak-period determination. Histograms of system activity are generated and presented to the user for peak-period determination; (2) Automatic clustering analysis. The data collected from the mass storage system logs is clustered using clustering algorithms and tightness measures to limit the number of generated clusters; (3) Reporting of varied file statistics. The tool computes several statistics on file sizes such as average, standard deviation, minimum, maximum, frequency, as well as average transfer time. These statistics are given on a per cluster basis; (4) Portability. The tool can easily be used to characterize the workload in mass storage systems of different vendors. The user needs to specify through a simple log description language how the a specific log should be interpreted. The rest of this paper is organized as follows. Section two presents basic concepts in workload characterization as they apply to mass storage systems. Section three describes clustering algorithms and tightness measures. The following section presents the architecture of the tool. Section five presents some results of workload characterization using the tool.Finally, section six presents some concluding remarks.
Ackermann, O; Heigel, U; Lazic, D; Vogel, T; Schofer, M D; Rülander, C
2012-04-01
For the clinical planning of mass events the emergency departments are of critical importance, but there are still no data available for the workload in these cases. As this is essential for an effective medical preparation, we calculated the workload based on the ICD codes of the vicitims at the Loveparade 2010 in Duisburg. Based on the patient data of the Loveparade 2010 we used a filter diagnosis to estimate the number of shock room patients, regular admittances, surgical wound treatments, applications of casts or splints, and diagnosis of drug abuse. In addition every patient was classified to a Manchester Triage System category. This resulted in a chronological and quantitative work-load profile of the emergency department, which was evaluated by the clinical experiences of the departmental medical staff. The workload profile as a whole displayed a realistic image of the real true situation on July 24, 2010. While only the number, diagnosis and chronology of medical surgical patients was realistic, the MTS classification was not. The emergency department had a maximum of 6 emergency room admittances, 6 regular admittances, 4-5 surgical wound treatments, 3 casts and 2 drug abuse patients per hour. The calculation of workload from the ICD data is a reasonable tool for retrospective estimation of the workload of an emergency department, the data can be used for future planning. The retrospective MTS grouping is at present not suitable for a realistic calculation. Retrospective measures in the MTS groups are at present not sufficiently suitable for valid data publication. © Georg Thieme Verlag KG Stuttgart · New York.
Huang, Chiung Shing; Cher, Tsang-Lie; Lin, Chun-Pin; Wu, Kai-Ming
2013-09-01
Planning of the dental workforce, especially the number of dentists, requires the data of actual dental workloads. This study attempts to make projections of the dental workforce from 2011 to 2020, based on a survey of the actual workload of 6762 dentists in 2010. In 2010, a database of 11,449 current dentists was retrieved from the file of Department of Health, Executive Yuan, Taipei, Taiwan. Questionnaires with the information of each dentist and 10 questions regarding the actual workload were sent to each dentist with a return envelope. The actual workload of the dentists who returned the questionnaires was analyzed. A projection of dental workforce from 2011 to 2020 was calculated, based on the actual workload. An analysis of the actual dental workload was conducted on 6762 (59.1%) returned questionnaires. The dentist-to-population ratio (defined as the number of dentists per 10,000 people) was 5.0 in 2010. The supply of 400 dentists per year remained constant from 2006 to 2010, and is expected to be sustained for the next 10 years. Because the population of Taiwan will begin to decrease within the next 10 years, we estimate that the dentist-to-population ratio will increase to 6.0 by the year 2020 or earlier. After adjusting for working hours, working days, and gender differences, surplus dentists will number approximately 1069 in 2020. An oversupply of dentists and a decrease in population will result in a surplus of dentists. To make better projections of the dental workforce, surplus dentists can be arranged to care for the aged, disabled people, and underserved people. Copyright © 2013. Published by Elsevier B.V.
Closed-loop, pilot/vehicle analysis of the approach and landing task
NASA Technical Reports Server (NTRS)
Schmidt, D. K.; Anderson, M. R.
1985-01-01
Optimal-control-theoretic modeling and frequency-domain analysis is the methodology proposed to evaluate analytically the handling qualities of higher-order manually controlled dynamic systems. Fundamental to the methodology is evaluating the interplay between pilot workload and closed-loop pilot/vehicle performance and stability robustness. The model-based metric for pilot workload is the required pilot phase compensation. Pilot/vehicle performance and loop stability is then evaluated using frequency-domain techniques. When these techniques were applied to the flight-test data for thirty-two highly-augmented fighter configurations, strong correlation was obtained between the analytical and experimental results.
Job and Workload Analysis System for Civil Servants in North Sulawesi Province, Indonesia
NASA Astrophysics Data System (ADS)
Krisnanda, M.; Mewengkang, A.; Rompas, P. T. D.; Togas, P. V.
2018-02-01
This study aims to create automation system to assist sub division of job analysis and workload of North Sulawesi, Indonesia in completing its annual tasks to record all civil servants. The method used in this research is prototyping where a system will be developed according to the revision supplied by the user. The result of this research is a system used to generate reports and calculations based on user filled forms. The result gathered from the interviews, users can make reports faster and easier. Users can also optimise reports on time using the built system.
A comparison of policies on nurse faculty workload in the United States.
Ellis, Peggy A
2013-01-01
This article describes nurse faculty workload policies from across the nation in order to assess current practice. There is a well-documented shortage of nursing faculty leading to an increase in workload demands. Increases in faculty workload results in difficulties with work-life balance and dissatisfaction threatening to make nursing education less attractive to young faculty. In order to begin an examination of faculty workload in nursing, existing workloads must be known. Faculty workload data were solicited from nursing programs nationwide and analyzed to determine the current workloads. The most common faculty teaching workload reported overall for nursing is 12 credit hours per semester; however, some variations exist. Consideration should be given to the multiple components of the faculty workload. Research is needed to address the most effective and efficient workload allocation for nursing faculty.
Understanding Cognitive Performance During Robot-Assisted Surgery.
Guru, Khurshid A; Shafiei, Somayeh B; Khan, Atif; Hussein, Ahmed A; Sharif, Mohamed; Esfahani, Ehsan T
2015-10-01
To understand cognitive function of an expert surgeon in various surgical scenarios while performing robot-assisted surgery. In an Internal Review Board approved study, National Aeronautics and Space Administration-Task Load Index (NASA-TLX) questionnaire with surgical field notes were simultaneously completed. A wireless electroencephalography (EEG) headset was used to monitor brain activity during all procedures. Three key portions were evaluated: lysis of adhesions, extended lymph node dissection, and urethro-vesical anastomosis (UVA). Cognitive metrics extracted were distraction, mental workload, and mental state. In evaluating lysis of adhesions, mental state (EEG) was associated with better performance (NASA-TLX). Utilizing more mental resources resulted in better performance as self-reported. Outcomes of lysis were highly dependent on cognitive function and decision-making skills. In evaluating extended lymph node dissection, there was a negative correlation between distraction level (EEG) and mental demand, physical demand and effort (NASA-TLX). Similar to lysis of adhesion, utilizing more mental resources resulted in better performance (NASA-TLX). Lastly, with UVA, workload (EEG) negatively correlated with mental and temporal demand and was associated with better performance (NASA-TLX). The EEG recorded workload as seen here was a combination of both cognitive performance (finding solution) and motor workload (execution). Majority of workload was contributed by motor workload of an expert surgeon. During UVA, muscle memory and motor skills of expert are keys to completing the UVA. Cognitive analysis shows that expert surgeons utilized different mental resources based on their need. Copyright © 2015 Elsevier Inc. All rights reserved.
Inflight workload assessment: comparison of subjective and physiological measurements.
Lee, Yung-Hui; Liu, Bor-Shong
2003-10-01
Assessment of pilot workload during flight is an important aviation safety consideration. The aim of this study was to assess inflight pilot workload using both physiological and multidimensional subjective-ratings measurements (heart rate and NASA Task Load Index, respectively), comparing relative sensitivity during the four phases of flight: take-off, cruise, approach, and landing. Ten male pilots volunteered to participate in the trials, which took place in a Boeing 747-400 flight simulator. Electrocardiography was performed throughout the test using the portable Cardiovis ECG system. Mean heart rate (HR) and incremental heart rate (delta HR) were considered indices of physiological workload. Peak HR was observed during take-off (83.2 bpm) and landing (88.6 bpm); moreover, delta HR was also greatest (14.2 bpm and 18.8 bpm). The Task Load Index (TLX) scale revealed that mental and performance demands were essential components of workload during flight. In addition, temporal demand was an important component of workload during take-off and physical demand was significant during cruise. Analysis of correlation revealed that the delta HR is significantly related to TLX scores (r = 0.81, n = 40). Management of the individual sources of stress, which tend to become predominant during different flight phases, should be emphasized in periodic recurrent training. For example, a pilot must be trained to cope with the increased temporal stresses associated with take-off. In addition, the recommendations will be concerned with maintaining vigilance, task allocation between pilots, and inflight rest during long-haul cruise.
Deeny, Sean; Chicoine, Caitlin; Hargrove, Levi; Parrish, Todd; Jayaraman, Arun
2014-01-01
Common goals in the development of human-machine interface (HMI) technology are to reduce cognitive workload and increase function. However, objective and quantitative outcome measures assessing cognitive workload have not been standardized for HMI research. The present study examines the efficacy of a simple event-related potential (ERP) measure of cortical effort during myoelectric control of a virtual limb for use as an outcome tool. Participants trained and tested on two methods of control, direct control (DC) and pattern recognition control (PRC), while electroencephalographic (EEG) activity was recorded. Eighteen healthy participants with intact limbs were tested using DC and PRC under three conditions: passive viewing, easy, and hard. Novel auditory probes were presented at random intervals during testing, and significant task-difficulty effects were observed in the P200, P300, and a late positive potential (LPP), supporting the efficacy of ERPs as a cognitive workload measure in HMI tasks. LPP amplitude distinguished DC from PRC in the hard condition with higher amplitude in PRC, consistent with lower cognitive workload in PRC relative to DC for complex movements. Participants completed trials faster in the easy condition using DC relative to PRC, but completed trials more slowly using DC relative to PRC in the hard condition. The results provide promising support for ERPs as an outcome measure for cognitive workload in HMI research such as prosthetics, exoskeletons, and other assistive devices, and can be used to evaluate and guide new technologies for more intuitive HMI control.
Effect of system workload on operating system reliability - A study on IBM 3081
NASA Technical Reports Server (NTRS)
Iyer, R. K.; Rossetti, D. J.
1985-01-01
This paper presents an analysis of operating system failures on an IBM 3081 running VM/SP. Three broad categories of software failures are found: error handling, program control or logic, and hardware related; it is found that more than 25 percent of software failures occur in the hardware/software interface. Measurements show that results on software reliability cannot be considered representative unless the system workload is taken into account. The overall CPU execution rate, although measured to be close to 100 percent most of the time, is not found to correlate strongly with the occurrence of failures. Possible reasons for the observed workload failure dependency, based on detailed investigations of the failure data, are discussed.
Distributed information system (water fact sheet)
Harbaugh, A.W.
1986-01-01
During 1982-85, the Water Resources Division (WRD) of the U.S. Geological Survey (USGS) installed over 70 large minicomputers in offices across the country to support its mission in the science of hydrology. These computers are connected by a communications network that allows information to be shared among computers in each office. The computers and network together are known as the Distributed Information System (DIS). The computers are accessed through the use of more than 1500 terminals and minicomputers. The WRD has three fundamentally different needs for computing: data management; hydrologic analysis; and administration. Data management accounts for 50% of the computational workload of WRD because hydrologic data are collected in all 50 states, Puerto Rico, and the Pacific trust territories. Hydrologic analysis consists of 40% of the computational workload of WRD. Cost accounting, payroll, personnel records, and planning for WRD programs occupies an estimated 10% of the computer workload. The DIS communications network is shown on a map. (Lantz-PTT)
A Process Analysis of the Uniform Chart of Accounts Personnel Utilization System
2002-04-23
business practices is evolving rapidly. The ever- changing health care environment requires all providers to be familiar with the costs of each...advised the standardization of the data used to develop them as well as the formulas for calculating them. These changes mostly related to workload...can also be used to determine site-specific capabilities and to identify potential areas for inter - service support of workload through sharing of
1991-01-01
and other higher order cognitive processe elevant to the design and use of the system. Characterization of human abilities and limitations in terms of...pilot’s workload and cognitive resources at any given moment. Before flight, the pilot can tailor the mode, type and quantity of information provided...it needs to incorporate models of human cognitive processes and resource limitations into the resource model. As mentioned earlier, characterization of
Workload and Stress in New Zealand Universities.
ERIC Educational Resources Information Center
Boyd, Sally; Wylie, Cathy
This study examined the workloads of academic, general, support, library, and technical staff of New Zealand universities. It focused on current levels of workload, changes in workload levels and content, connections between workload and stress, and staff attitudes towards the effects of workload changes and educational reforms on the quality of…
The effects of workload on respiratory variables in simulated flight: a preliminary study.
Karavidas, Maria Katsamanis; Lehrer, Paul M; Lu, Shou-En; Vaschillo, Evgeny; Vaschillo, Bronya; Cheng, Andrew
2010-04-01
In this pilot study, we investigated respiratory activity and end-tidal carbon dioxide (P(et)CO(2)) during exposure to varying levels of work load in a simulated flight environment. Seven pilots (age: 34-60) participated in a one-session test on the Boeing 737-800 simulator. Physiological data were collected while pilots wore an ambulatory multi-channel recording device. Respiratory variables, including inductance plethysmography (respiratory pattern) and pressure of end-tidal carbon dioxide (P(et)CO(2)), were collected demonstrating change in CO(2) levels proportional to changes in flight task workload. Pilots performed a set of simulation flight tasks. Pilot performance was rated for each task by a test pilot; and self-report of workload was taken using the NASA-TLX scale. Mixed model analysis revealed that respiration rate and minute ventilation are significantly associated with workload levels and evaluator scores controlling for "vanilla baseline" condition. Hypocapnia exclusively occurred in tasks where pilots performed more poorly. This study was designed as a preliminary investigation in order to develop a psychophysiological assessment methodology, rather than to offer conclusive findings. The results show that the respiratory system is very reactive to high workload conditions in aviation and suggest that hypocapnia may pose a flight safety risk under some circumstances. Copyright © 2010 Elsevier B.V. All rights reserved.
Relation Between Physicians' Work Lives and Happiness.
Eckleberry-Hunt, Jodie; Kirkpatrick, Heather; Taku, Kanako; Hunt, Ronald; Vasappa, Rashmi
2016-04-01
Although we know much about work-related physician burnout and the subsequent negative effects, we do not fully understand work-related physician wellness. Likewise, the relation of wellness and burnout to physician happiness is unclear. The purpose of this study was to examine how physician burnout and wellness contribute to happiness. We sampled 2000 full-time physician members of the American Academy of Family Physicians. Respondents completed a demographics questionnaire, questions about workload, the Physician Wellness Inventory, the Maslach Burnout Inventory, and the Subjective Happiness Scale. We performed a hierarchical regression analysis with the burnout and wellness subscales as predictor variables and physician happiness as the outcome variable. Our response rate was 22%. Career purpose, personal accomplishment, and perception of workload manageability had significant positive correlations with physician happiness. Distress had a significant negative correlation with physician happiness. A sense of career meaning and accomplishment, along with a lack of distress, are important factors in determining physician happiness. The number of hours a physician works is not related to happiness, but the perceived ability to manage workload was significantly related to happiness. Wellness-promotion efforts could focus on assisting physicians with skills to manage the workload by eliminating unnecessary tasks or sharing workload among team members, improving feelings of work accomplishment, improving career satisfaction and meaning, and managing distress related to patient care.
NASA Technical Reports Server (NTRS)
Hase, Chris
2010-01-01
In August 2003, the Secretary of Defense (SECDEF) established the Adaptive Planning (AP) initiative [1] with an objective of reducing the time necessary to develop and revise Combatant Commander (COCOM) contingency plans and increase SECDEF plan visibility. In addition to reducing the traditional plan development timeline from twenty-four months to less than twelve months (with a goal of six months)[2], AP increased plan visibility to Department of Defense (DoD) leadership through In-Progress Reviews (IPRs). The IPR process, as well as the increased number of campaign and contingency plans COCOMs had to develop, increased the workload while the number of planners remained fixed. Several efforts from collaborative planning tools to streamlined processes were initiated to compensate for the increased workload enabling COCOMS to better meet shorter planning timelines. This paper examines the Joint Strategic Capabilities Plan (JSCP) directed contingency planning and staffing requirements assigned to a combatant commander staff through the lens of modeling and simulation. The dynamics of developing a COCOM plan are captured with an ExtendSim [3] simulation. The resulting analysis provides a quantifiable means by which to measure a combatant commander staffs workload associated with development and staffing JSCP [4] directed contingency plans with COCOM capability/capacity. Modeling and simulation bring significant opportunities in measuring the sensitivity of key variables in the assessment of workload to capability/capacity analysis. Gaining an understanding of the relationship between plan complexity, number of plans, planning processes, and number of planners with time required for plan development provides valuable information to DoD leadership. Through modeling and simulation AP leadership can gain greater insight in making key decisions on knowing where to best allocate scarce resources in an effort to meet DoD planning objectives.
Fallahi, Majid; Motamedzade, Majid; Heidarimoghadam, Rashid; Soltanian, Ali Reza; Miyake, Shinji
2016-01-01
Background: The present study aimed to evaluate the operators’ mental workload (MW) of cement, city traffic control and power plant control centers using subjective and objective measures during system vital parameters monitoring. Methods: This cross-sectional study was conducted from June 2014 to February 2015 at the cement, city traffic control and power plant control centers. Electrocardiography and electroencephalography data were recorded from forty males during performing their daily working in resting, low mental workload (LMW), high mental workload (HMW) and recovery conditions (each block 5 minutes). The NASA-Task Load Index (TLX) was used to evaluate the subjective workload of the operators. Results: The results showed that increasing MW had a significant effect on the operators subjective responses in two conditions ([1,53] = 216.303, P < 0.001, η2 = 0.803). Also,the Task-MW interaction effect on operators subjective responses was significant (F [3, 53] = 12.628,P < 0.001, η2 = 0.417). Analysis of repeated measures analysis of variance (ANOVA) indicated that increasing mental demands had a significant effect on heart rate, low frequency/high frequency ratio, theta and alpha band activity. Conclusion: The results suggested that when operators’ mental demands especially in traffic control and power plant tasks increased, their mental fatigue and stress level increased and their mental health deteriorated. Therefore, it may be necessary to implement an ergonomic program or administrative control to manage mental probably health in these control centers. Furthermore, by evaluating MW, the control center director can organize the human resources for each MW condition to sustain the appropriate performance as well as improve system functions. PMID:27386425
Fallahi, Majid; Motamedzade, Majid; Heidarimoghadam, Rashid; Soltanian, Ali Reza; Miyake, Shinji
2016-01-01
The present study aimed to evaluate the operators' mental workload (MW) of cement, city traffic control and power plant control centers using subjective and objective measures during system vital parameters monitoring. This cross-sectional study was conducted from June 2014 to February 2015 at the cement, city traffic control and power plant control centers. Electrocardiography and electroencephalography data were recorded from forty males during performing their daily working in resting, low mental workload (LMW), high mental workload (HMW) and recovery conditions (each block 5 minutes). The NASA-Task Load Index (TLX) was used to evaluate the subjective workload of the operators. The results showed that increasing MW had a significant effect on the operators subjective responses in two conditions ([1,53] = 216.303, P < 0.001, η2 = 0.803). Also,the Task-MW interaction effect on operators subjective responses was significant (F [3, 53] = 12.628,P < 0.001, η2 = 0.417). Analysis of repeated measures analysis of variance (ANOVA) indicated that increasing mental demands had a significant effect on heart rate, low frequency/high frequency ratio, theta and alpha band activity. The results suggested that when operators' mental demands especially in traffic control and power plant tasks increased, their mental fatigue and stress level increased and their mental health deteriorated. Therefore, it may be necessary to implement an ergonomic program or administrative control to manage mental probably health in these control centers. Furthermore, by evaluating MW, the control center director can organize the human resources for each MW condition to sustain the appropriate performance as well as improve system functions.
Module Cluster: TLA-004.00 (GSC) Teaching Language Arts in the Elementary School.
ERIC Educational Resources Information Center
Mignogna, William D.
The purpose of this module cluster is to enable students to a) identify the areas that the language arts focus on in the elementary school; b) analyze and synthesize expressive and receptive skills as they relate to the language arts program; c) demonstrate a knowledge of and skill in the use of a variety of techniques and materials for teaching…
Sub-poissonian photon statistics in the coherent state Jaynes-Cummings model in non-resonance
NASA Astrophysics Data System (ADS)
Zhang, Jia-tai; Fan, An-fu
1992-03-01
We study a model with a two-level atom (TLA) non-resonance interacting with a single-mode quantized cavity field (QCF). The photon number probability function, the mean photon number and Mandel's fluctuation parameter are calculated. The sub-Poissonian distributions of the photon statistics are obtained in non-resonance interaction. This statistical properties are strongly dependent on the detuning parameters.
On the influence of anharmonicity on the isotope effect
NASA Astrophysics Data System (ADS)
Galbaatar, T.; Drechsler, S. L.; Plakida, N. M.; Vujicic, G. M.
1991-12-01
The effect of double-well type lattice anharmonicity on the superconducting temperature and its isotope effect is investigated beyond the two-level approximation (TLA) within the Eliashberg theory. It is shown that anharmonicity can greatly modify the isotope effect; In particular anomalously large as well as negative values of the isotope effect exponent α are obtained in the strong and weak coupling limits, respectively.
Schneid, Stephen D; Armour, Chris; Park, Yoon Soo; Yudkowsky, Rachel; Bordage, Georges
2014-10-01
Despite significant evidence supporting the use of three-option multiple-choice questions (MCQs), these are rarely used in written examinations for health professions students. The purpose of this study was to examine the effects of reducing four- and five-option MCQs to three-option MCQs on response times, psychometric characteristics, and absolute standard setting judgements in a pharmacology examination administered to health professions students. We administered two versions of a computerised examination containing 98 MCQs to 38 Year 2 medical students and 39 Year 3 pharmacy students. Four- and five-option MCQs were converted into three-option MCQs to create two versions of the examination. Differences in response time, item difficulty and discrimination, and reliability were evaluated. Medical and pharmacy faculty judges provided three-level Angoff (TLA) ratings for all MCQs for both versions of the examination to allow the assessment of differences in cut scores. Students answered three-option MCQs an average of 5 seconds faster than they answered four- and five-option MCQs (36 seconds versus 41 seconds; p = 0.008). There were no significant differences in item difficulty and discrimination, or test reliability. Overall, the cut scores generated for three-option MCQs using the TLA ratings were 8 percentage points higher (p = 0.04). The use of three-option MCQs in a health professions examination resulted in a time saving equivalent to the completion of 16% more MCQs per 1-hour testing period, which may increase content validity and test score reliability, and minimise construct under-representation. The higher cut scores may result in higher failure rates if an absolute standard setting method, such as the TLA method, is used. The results from this study provide a cautious indication to health professions educators that using three-option MCQs does not threaten validity and may strengthen it by allowing additional MCQs to be tested in a fixed amount of testing time with no deleterious effect on the reliability of the test scores. © 2014 John Wiley & Sons Ltd.
2003-03-01
benefit to showing the line community, DoD, Congress and others how the work performed is related to, enhances, or adds value to the readiness mission...Describing the Type of Work Seen in Same Day Surgery (SDS) ..54 5. Relationship Between Inpatient Dispositions and SDS Cases .......57 E. CONCLUSION...Outpatient Ratio of Work per Surgical Specialty .....................115 Figure 26. Ratio of Workload to the Number of Emergency Medicine Doctors
Effects of Automation on Aircrew Workload and Situation Awareness in Tactical Airlift Missions
2015-12-24
autopilot (Hall, 1996; FAA). The inability of the crew to manually override the autopilot and mode confusion was causal to the Exxon Valdez oil spill...malfunctioned. In the case of a loss in propeller hydraulic fluid (“Prop Low Oil ” light), a warning light illuminates on the engine instrument stack...2013). Analysis of workload of tank crew under the conditions of informatization . Beijing: China North Vehicle Research Institute. Martin, G
2005-12-01
60 x THIS PAGE INTENTIONALLY LEFT BLANK xi LIST OF TABLES Table 1...anywhere from one minute to several hours, depending on the needs of the analyst. The models generated for this thesis were set to run for 60 ...of a workload threshold goes back to the original LHX analysis from McCracken and Aldrich (1984). The IMPRINT 59 workload value of 60 has been
Spikes in acute workload are associated with increased injury risk in elite cricket fast bowlers.
Hulin, Billy T; Gabbett, Tim J; Blanch, Peter; Chapman, Paul; Bailey, David; Orchard, John W
2014-04-01
To determine if the comparison of acute and chronic workload is associated with increased injury risk in elite cricket fast bowlers. Data were collected from 28 fast bowlers who completed a total of 43 individual seasons over a 6-year period. Workloads were estimated by summarising the total number of balls bowled per week (external workload), and by multiplying the session rating of perceived exertion by the session duration (internal workload). One-week data (acute workload), together with 4-week rolling average data (chronic workload), were calculated for external and internal workloads. The size of the acute workload in relation to the chronic workload provided either a negative or positive training-stress balance. A negative training-stress balance was associated with an increased risk of injury in the week after exposure, for internal workload (relative risk (RR)=2.2 (CI 1.91 to 2.53), p=0.009), and external workload (RR=2.1 (CI 1.81 to 2.44), p=0.01). Fast bowlers with an internal workload training-stress balance of greater than 200% had a RR of injury of 4.5 (CI 3.43 to 5.90, p=0.009) compared with those with a training-stress balance between 50% and 99%. Fast bowlers with an external workload training-stress balance of more than 200% had a RR of injury of 3.3 (CI 1.50 to 7.25, p=0.033) in comparison to fast bowlers with an external workload training-stress balance between 50% and 99%. These findings demonstrate that large increases in acute workload are associated with increased injury risk in elite cricket fast bowlers.
NASA Technical Reports Server (NTRS)
James, Jeffrey M.; Sanderson, Penelope M.; Seidler, Karen S.
1990-01-01
As modern transport environments become increasingly complex, issues such as crew communication, interaction with automation, and workload management have become crucial. Much research is being focused on holistic aspects of social and cognitive behavior, such as the strategies used to handle workload, the flow of information, the scheduling of tasks, the verbal and non-verbal interactions between crew members. Traditional laboratory performance measures no longer sufficiently meet the needs of researchers addressing these issues. However observational techniques are better equipped to capture the type of data needed and to build models of the requisite level of sophistication. Presented here is SHAPA, an interactive software tool for performing both verbal and non-verbal protocol analysis. It has been developed with the idea of affording the researchers the closest possible degree of engagement with protocol data. The researcher can configure SHAPA to encode protocols using any theoretical framework or encoding vocabulary that is desired. SHAPA allows protocol analysis to be performed at any level of analysis, and it supplies a wide variety of tools for data aggregation, manipulation. The output generated by SHAPA can be used alone or in combination with other performance variables to get a rich picture of the influences on sequences of verbal or nonverbal behavior.
Physician activity during outpatient visits and subjective workload.
Calvitti, Alan; Hochheiser, Harry; Ashfaq, Shazia; Bell, Kristin; Chen, Yunan; El Kareh, Robert; Gabuzda, Mark T; Liu, Lin; Mortensen, Sara; Pandey, Braj; Rick, Steven; Street, Richard L; Weibel, Nadir; Weir, Charlene; Agha, Zia
2017-05-01
We describe methods for capturing and analyzing EHR use and clinical workflow of physicians during outpatient encounters and relating activity to physicians' self-reported workload. We collected temporally-resolved activity data including audio, video, EHR activity, and eye-gaze along with post-visit assessments of workload. These data are then analyzed through a combination of manual content analysis and computational techniques to temporally align streams, providing a range of process measures of EHR usage, clinical workflow, and physician-patient communication. Data was collected from primary care and specialty clinics at the Veterans Administration San Diego Healthcare System and UCSD Health, who use Electronic Health Record (EHR) platforms, CPRS and Epic, respectively. Grouping visit activity by physician, site, specialty, and patient status enables rank-ordering activity factors by their correlation to physicians' subjective work-load as captured by NASA Task Load Index survey. We developed a coding scheme that enabled us to compare timing studies between CPRS and Epic and extract patient and visit complexity profiles. We identified similar patterns of EHR use and navigation at the 2 sites despite differences in functions, user interfaces and consequent coded representations. Both sites displayed similar proportions of EHR function use and navigation, and distribution of visit length, proportion of time physicians attended to EHRs (gaze), and subjective work-load as measured by the task load survey. We found that visit activity was highly variable across individual physicians, and the observed activity metrics ranged widely as correlates to subjective workload. We discuss implications of our study for methodology, clinical workflow and EHR redesign. Copyright © 2017 Elsevier Inc. All rights reserved.
Neupane, Subas; Pensola, Tiina; Haukka, Eija; Ojajärvi, Anneli; Leino-Arjas, Päivi
2016-07-01
Previously, among food industry workers, multisite pain predicted sickness absence (SA) only in those with low biomechanical workload. Here we studied among a wide range of occupations whether the relationship of pain with SA was modified by the level of physical or psychosocial workload. A nationally representative sample (Health 2000 Survey) comprised 3420 occupationally active Finns aged 30-55 years. Baseline data on musculoskeletal pain during the preceding month, strenuous work history, current physical workload, job demands, job control, support at work, lifestyle, and chronic diseases were obtained in 2000/2001 by questionnaire, interview, and clinical examination. Musculoskeletal pain in 18 body locations was combined into four sites (neck, upper limbs, low back, and lower limbs) and classified as no pain, single-site pain, and multisite pain (2-4 sites). The data were linked with information from national registers on annual SA periods lasting ≥10 workdays for 2002-2008. Negative binomial regression analysis was used. At baseline, one-third of the study sample reported single-site and one-third multisite pain. Allowing for gender and age, the employees with multisite pain in strata with high physical workload and high job demands tended to have the highest risk of SA, but no statistically significant interactive effects between work factors and pain were observed. Further adjustment for health-related lifestyle and chronic diseases decreased the risk estimates in all strata. We did not find evidence for significant modification by physical or psychosocial workload of the relationship between musculoskeletal pain and SA periods lasting ≥10 workdays.
Korshøj, Mette; Lidegaard, Mark; Krustrup, Peter; Jørgensen, Marie Birk; Søgaard, Karen; Holtermann, Andreas
2016-01-01
Objectives Occupational groups exposed to high occupational physical activity have an increased risk for cardiovascular disease (CVD). This may be explained by the high relative aerobic workload. Enhanced cardiorespiratory fitness reduces the relative aerobic workload. Thus, the aim was to evaluate the 12-months effects of worksite aerobic exercise on risk factors for CVD among cleaners. Methods One hundred and sixteen cleaners aged 18–65 years were randomized to a group performing aerobic exercise and a reference group receiving lectures. Outcomes were collected at baseline and after 12-months. A repeated measures 2×2 multi-adjusted mixed-model design was applied to compare the between-group differences using intention-to-treat analysis. Results Between-group differences (p<0.05) were found favouring the aerobic exercise group: cardiorespiratory fitness 2.15 (SE 1.03) mlO2/min/kg, aerobic workload -2.15 (SE 1.06) %HRR, resting HR -5.31 (SE 1.61) beats/min, high sensitive C-reactive protein -0.65 (SE 0.24) μg/ml. The blood pressure was unaltered. Stratified analyses on relative aerobic workload at baseline revealed that those with relative aerobic workloads ≥30% of HRR seems to impose a notable adverse effect on resting and ambulatory blood pressure. Conclusion This long-term worksite aerobic exercise intervention among cleaners led to several beneficial effects, but also potential adverse effects among those with high relative aerobic workloads. Trial Registration Controlled-Trials.com ISRCTN86682076 PMID:27513932
Gallienne, Jacqueline; Gregg, Caroline; LeBlanc, Evan; Yaakob, Norazlin; Wu, Di; Davies, Kate; Rawlings, Norman; Pierson, Roger; Deardon, Rob; Bartlewski, Pawel
2012-05-01
Associations between physical characteristics and functionality of corpora lutea (CL) have previously been reported in monovulatory species, albeit several studies in cattle and humans have refuted the existence of temporal relationships between CL size, echotexture and serum progesterone (P(4)) concentrations. The main objective of the present study was to examine whether or not there were correlations between ultrasonographic image attributes of CL and systemic concentrations of P(4) during the discrete stages of the luteal phase in two breeds of sheep differing in ovulation rates (non-prolific Western White Face [WWF] ewes and prolific Finn [F] sheep). Transrectal ovarian ultrasonography utilized a 7.5-MHz linear-array transducer connected to a portable scanner (Aloka SSD-500) and the images were analyzed using commercially available image analytical software (Image ProPlus(®)) validated for the present application in sheep. The correlations were assessed using the Pearson's Product Moment (PPM) analysis and also, to increase the accuracy of statistical tests, the analysis of covariance (ANCOVA), with the number of CL as a co-factor. In WWF ewes, serum concentrations of P(4) correlated significantly with the total luteal area (TLA) during the CL growth phase (days 3-6; day 0 = ovulation) and functional luteolysis (days 12-15), and with numerical pixel values (NPVs--pixel intensity) during luteolysis; the results obtained by using two different statistical methods were generally similar. In prolific F ewes, serum P(4) concentrations were directly correlated with TLA during CL growth (days 3-6; ANCOVA), functional luteolysis (days 13-14; PPM), and structural CL regression (days 11-14; PPM and ANCOVA), and with NPVs during functional luteolysis (PPM and ANCOVA). We concluded that systemic P(4) concentrations could only be accurately predicted from the changes in luteal area during CL growth and regression, and from NPVs during luteolysis, in both prolific and non-prolific ewes, but the changes in size and echotexture of the luteal glands at mid-cycle were not indicative of serum P(4) concentrations in sheep.
Da Silva, David; Han, Liqi; Faivre, Robert; Costes, Evelyne
2014-01-01
Background and Aims The impact of a fruit tree's architecture on its performance is still under debate, especially with regard to the definition of varietal ideotypes and the selection of architectural traits in breeding programmes. This study aimed at providing proof that a modelling approach can contribute to this debate, by using in silico exploration of different combinations of traits and their consequences on light interception, here considered as one of the key parameters to optimize fruit tree production. Methods The variability of organ geometrical traits, previously described in a bi-parental population, was used to simulate 1- to 5-year-old apple trees (Malus × domestica). Branching sequences along trunks observed during the first year of growth of the same hybrid trees were used to initiate the simulations, and hidden semi-Markov chains previously parameterized were used in subsequent years. Tree total leaf area (TLA) and silhouette to total area ratio (STAR) values were estimated, and a sensitivity analysis was performed, based on a metamodelling approach and a generalized additive model (GAM), to analyse the relative impact of organ geometry and lateral shoot types on STAR. Key Results A larger increase over years in TLA mean and variance was generated by varying branching along trunks than by varying organ geometry, whereas the inverse was observed for STAR, where mean values stabilized from year 3 to year 5. The internode length and leaf area had the highest impact on STAR, whereas long sylleptic shoots had a more significant effect than proleptic shoots. Although the GAM did not account for interactions, the additive effects of the geometrical factors explained >90% of STAR variation, but much less in the case of branching factors. Conclusions This study demonstrates that the proposed modelling approach could contribute to screening architectural traits and their relative impact on tree performance, here viewed through light interception. Even though trait combinations and antagonism will need further investigation, the approach opens up new perspectives for breeding and genetic selection to be assisted by varietal ideotype definition. PMID:24723446
Evaluation of the Display of Cognitive State Feedback to Drive Adaptive Task Sharing
Dorneich, Michael C.; Passinger, Břetislav; Hamblin, Christopher; Keinrath, Claudia; Vašek, Jiři; Whitlow, Stephen D.; Beekhuyzen, Martijn
2017-01-01
This paper presents an adaptive system intended to address workload imbalances between pilots in future flight decks. Team performance can be maximized when task demands are balanced within crew capabilities and resources. Good communication skills enable teams to adapt to changes in workload, and include the balancing of workload between team members This work addresses human factors priorities in the aviation domain with the goal to develop concepts that balance operator workload, support future operator roles and responsibilities, and support new task requirements, while allowing operators to focus on the most safety critical tasks. A traditional closed-loop adaptive system includes the decision logic to turn automated adaptations on and off. This work takes a novel approach of replacing the decision logic, normally performed by the automation, with human decisions. The Crew Workload Manager (CWLM) was developed to objectively display the workload between pilots and recommend task sharing; it is then the pilots who “close the loop” by deciding how to best mitigate unbalanced workload. The workload was manipulated by the Shared Aviation Task Battery (SAT-B), which was developed to provide opportunities for pilots to mitigate imbalances in workload between crew members. Participants were put in situations of high and low workload (i.e., workload was manipulated as opposed to being measured), the workload was then displayed to pilots, and pilots were allowed to decide how to mitigate the situation. An evaluation was performed that utilized the SAT-B to manipulate workload and create workload imbalances. Overall, the CWLM reduced the time spent in unbalanced workload and improved the crew coordination in task sharing while not negatively impacting concurrent task performance. Balancing workload has the potential to improve crew resource management and task performance over time, and reduce errors and fatigue. Paired with a real-time workload measurement system, the CWLM could help teams manage their own task load distribution. PMID:28400716
Evaluation of the Display of Cognitive State Feedback to Drive Adaptive Task Sharing.
Dorneich, Michael C; Passinger, Břetislav; Hamblin, Christopher; Keinrath, Claudia; Vašek, Jiři; Whitlow, Stephen D; Beekhuyzen, Martijn
2017-01-01
This paper presents an adaptive system intended to address workload imbalances between pilots in future flight decks. Team performance can be maximized when task demands are balanced within crew capabilities and resources. Good communication skills enable teams to adapt to changes in workload, and include the balancing of workload between team members This work addresses human factors priorities in the aviation domain with the goal to develop concepts that balance operator workload, support future operator roles and responsibilities, and support new task requirements, while allowing operators to focus on the most safety critical tasks. A traditional closed-loop adaptive system includes the decision logic to turn automated adaptations on and off. This work takes a novel approach of replacing the decision logic, normally performed by the automation, with human decisions. The Crew Workload Manager (CWLM) was developed to objectively display the workload between pilots and recommend task sharing; it is then the pilots who "close the loop" by deciding how to best mitigate unbalanced workload. The workload was manipulated by the Shared Aviation Task Battery (SAT-B), which was developed to provide opportunities for pilots to mitigate imbalances in workload between crew members. Participants were put in situations of high and low workload (i.e., workload was manipulated as opposed to being measured), the workload was then displayed to pilots, and pilots were allowed to decide how to mitigate the situation. An evaluation was performed that utilized the SAT-B to manipulate workload and create workload imbalances. Overall, the CWLM reduced the time spent in unbalanced workload and improved the crew coordination in task sharing while not negatively impacting concurrent task performance. Balancing workload has the potential to improve crew resource management and task performance over time, and reduce errors and fatigue. Paired with a real-time workload measurement system, the CWLM could help teams manage their own task load distribution.
U.S. Coast Guard SARSAT Final Evaluation Report. Volume II. Appendices.
DOT National Transportation Integrated Search
1987-03-01
Contents: Controlled Tests; Controlled Test Error Analysis, Processing of Westwind Data; Exercises and Homing Tests; Further Analysis of Controlled Tests; Sar Case Analysis Tables; Narratives of Real Distress Cases; RCC Response Scenarios; Workload A...
[Effects of mental workload on work ability in primary and secondary school teachers].
Xiao, Yuanmei; Li, Weijuan; Ren, Qingfeng; Ren, Xiaohui; Wang, Zhiming; Wang, Mianzhen; Lan, Yajia
2015-02-01
To investigate the change pattern of primary and secondary school teachers' work ability with the changes in their mental workload. A total of 901 primary and secondary school teachers were selected by random cluster sampling, and then their mental workload and work ability were assessed by National Aeronautics and Space Administration-Task Load Index (NASA-TLX) and Work Ability Index (WAI) questionnaires, whose reliability and validity had been tested. The effects of their mental workload on the work ability were analyzed. Primary and secondary school teachers' work ability reached the highest level at a certain level of mental workload (55.73< mental workload ≤ 64.10). When their mental workload was lower than the level, their work ability had a positive correlation with the mental workload. Their work ability increased or maintained stable with the increasing mental workload. Moreover, the percentage of teachers with good work ability increased, while that of teachers with moderate work ability decreased. But when their mental workload was higher than the level, their work ability had a negative correlation with the mental workload. Their work ability significantly decreased with the increasing mental workload (P < 0.01). Furthermore, the percentage of teachers with good work ability decreased, while that of teachers with moderate work ability increased (P < 0.001). Too high or low mental workload will result in the decline of primary and secondary school teachers' work ability. Moderate mental workload (55.73∼64.10) will benefit the maintaining and stabilization of their work ability.
Workflow Management Systems for Molecular Dynamics on Leadership Computers
NASA Astrophysics Data System (ADS)
Wells, Jack; Panitkin, Sergey; Oleynik, Danila; Jha, Shantenu
Molecular Dynamics (MD) simulations play an important role in a range of disciplines from Material Science to Biophysical systems and account for a large fraction of cycles consumed on computing resources. Increasingly science problems require the successful execution of ''many'' MD simulations as opposed to a single MD simulation. There is a need to provide scalable and flexible approaches to the execution of the workload. We present preliminary results on the Titan computer at the Oak Ridge Leadership Computing Facility that demonstrate a general capability to manage workload execution agnostic of a specific MD simulation kernel or execution pattern, and in a manner that integrates disparate grid-based and supercomputing resources. Our results build upon our extensive experience of distributed workload management in the high-energy physics ATLAS project using PanDA (Production and Distributed Analysis System), coupled with recent conceptual advances in our understanding of workload management on heterogeneous resources. We will discuss how we will generalize these initial capabilities towards a more production level service on DOE leadership resources. This research is sponsored by US DOE/ASCR and used resources of the OLCF computing facility.
Implementation of a model of emergency care in an Australian hospital.
Millichamp, Tracey; Bakon, Shannon; Christensen, Martin; Stock, Kate; Howarth, Sarah
2017-11-10
Emergency departments are characterised by a fast-paced, quick turnover and high acuity workload, therefore appropriate staffing is vital to ensure positive patient outcomes. Models of care are frameworks in which safe and effective patient-to-nurse ratios can be ensured. The aim of this study was to implement a supportive and transparent model of emergency nursing care that provides structure - regardless of nursing staff profile, business or other demands; improvement to nursing workloads; and promotes individual responsibility and accountability for patient care. A convergent parallel mixed-method approach was used. Quantitative data were analysed using descriptive statistics and the qualitative data used a thematic analysis to identify recurrent themes. Data post-implementation of the model of emergency nursing care indicate improved staff satisfaction in relation to workload, patient care and support structures. The development and implementation of a model of care in an emergency department improved staff workload and staff's perception of their ability to provide care. ©2017 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.
Heavy vehicle driver workload assessment. Task 4, review of workload and related research
DOT National Transportation Integrated Search
This report reviews literature on workload measures and related research. It depicts the preliminary development of a theoretical basis for relating driving workload to highway safety and a selective review of driver performance evaluation, workload ...
Transport pilot workload - A comparison of two subjective techniques
NASA Technical Reports Server (NTRS)
Battiste, Vernol; Bortolussi, Michael
1988-01-01
Although SWAT and NASA-TLX workload scales have been compared on numerous occasions, they have not been compared in the context of transport operations. Transport pilot workload has traditionally been classified as long periods of low workload with occasional spikes of high workload. Thus, the relative sensitivity of the scales to variations in workload at the low end of the scale were evaluated. This study was a part of a larger study which investigated workload measures for aircraft certification, conducted in a Phase II certified Link/Boeing 727 simulator. No significant main effects were found for any performance-based measures of workload. However, both SWAT and NASA-TLX were sensitive to differences between high and low workload flights and to differences among flight segments. NASA-TLX (but not SWAT) was sensitive to the increase in workload during the cruise segment of the high workload flight. Between-subject variability was high for SWAT. NASA-TLX was found to be stable when compared in the test/retest paradigm. A test/retest by segment interaction suggested that this was not the case for SWAT ratings.
Reconsidering the conceptualization of nursing workload: literature review.
Morris, Roisin; MacNeela, Padraig; Scott, Anne; Treacy, Pearl; Hyde, Abbey
2007-03-01
This paper reports a literature review that aimed to analyse the way in which nursing intensity and patient dependency have been considered to be conceptually similar to nursing workload, and to propose a model to show how these concepts actually differ in both theoretical and practical terms. The literature on nursing workload considers the concepts of patient 'dependency' and nursing 'intensity' in the realm of nursing workload. These concepts differ by definition but are used to measure the same phenomenon, i.e. nursing workload. The literature search was undertaken in 2004 using electronic databases, reference lists and other available literature. Papers were sourced from the Medline, Psychlit, CINAHL and Cochrane databases and through the general search engine Google. The keywords focussed on nursing workload, nursing intensity and patient dependency. Nursing work and workload concepts and labels are defined and measured in different and often contradictory ways. It is vitally important to understand these differences when using such conceptualizations to measure nursing workload. A preliminary model is put forward to clarify the relationships between nursing workload concepts. In presenting a preliminary model of nursing workload, it is hoped that nursing workload might be better understood so that it becomes more visible and recognizable. Increasing the visibility of nursing workload should have a positive impact on nursing workload management and on the provision of patient care.
NASA Technical Reports Server (NTRS)
Damos, D. L.
1984-01-01
Human factors practitioners often are concerned with mental workload in multiple-task situations. Investigations of these situations have demonstrated repeatedly that individuals differ in their subjective estimates of workload. These differences may be attributed in part to individual differences in definitions of workload. However, after allowing for differences in the definition of workload, there are still unexplained individual differences in workload ratings. The relation between individual differences in multiple-task performance, subjective estimates of workload, information processing abilities, and the Type A personality trait were examined.
2014-12-01
research, several boundaries have been imposed to focus this thesis. 1. Scope This thesis is not a wholesale analysis of workload studies in...focus of this thesis. 2. Limitations Multiple factors, including mental and physical fatigue, influence crew endurance. More sleep of higher...support crew endurance are physical fitness, diet and nutrition, use of technology to reduce workload, reasonable living conditions, adequate manning
Workload Analysis of the Crew of the Abrams V2 SEP: Phase I Baseline IMPRINT Model
2009-09-01
PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Army Research Laboratory ATTN: RDRL- HRM -B Aberdeen Proving Ground, MD 21005-5425 8...running a stop sign or a deer darting across the road, the high workload demands of driving become more apparent. The frequency of automobile accidents...OF COPIES ORGANIZATION COPIES ORGANIZATION 29 1 ARMY RSCH LABORATORY – HRED RDRL HRM A J MARTIN MYER CENTER BLDG 2700 RM 2D311
Interactive Query Processing in Big Data Systems: A Cross Industry Study of MapReduce Workloads
2012-04-02
invite cluster operators and the broader data management commu- nity to share additional knowledge about their MapReduce workloads. 9. ACKNOWLEDGMENTS...against real- life production MapReduce workloads. Knowledge of such workloads is currently limited to a handful of technology companies [19, 8, 48, 41...database management insights would benefit from checking workload assumptions against empirical measurements. The broad spectrum of workloads analyzed allows
Lee, Gyusung I; Lee, Mija R; Clanton, Tameka; Clanton, Tamera; Sutton, Erica; Park, Adrian E; Marohn, Michael R
2014-02-01
We conducted this study to investigate how physical and cognitive ergonomic workloads would differ between robotic and laparoscopic surgeries and whether any ergonomic differences would be related to surgeons' robotic surgery skill level. Our hypothesis is that the unique features in robotic surgery will demonstrate skill-related results both in substantially less physical and cognitive workload and uncompromised task performance. Thirteen MIS surgeons were recruited for this institutional review board-approved study and divided into three groups based on their robotic surgery experiences: laparoscopy experts with no robotic experience, novices with no or little robotic experience, and robotic experts. Each participant performed six surgical training tasks using traditional laparoscopy and robotic surgery. Physical workload was assessed by using surface electromyography from eight muscles (biceps, triceps, deltoid, trapezius, flexor carpi ulnaris, extensor digitorum, thenar compartment, and erector spinae). Mental workload assessment was conducted using the NASA-TLX. The cumulative muscular workload (CMW) from the biceps and the flexor carpi ulnaris with robotic surgery was significantly lower than with laparoscopy (p < 0.05). Interestingly, the CMW from the trapezius was significantly higher with robotic surgery than with laparoscopy (p < 0.05), but this difference was only observed in laparoscopic experts (LEs) and robotic surgery novices. NASA-TLX analysis showed that both robotic surgery novices and experts expressed lower global workloads with robotic surgery than with laparoscopy, whereas LEs showed higher global workload with robotic surgery (p > 0.05). Robotic surgery experts and novices had significantly higher performance scores with robotic surgery than with laparoscopy (p < 0.05). This study demonstrated that the physical and cognitive ergonomics with robotic surgery were significantly less challenging. Additionally, several ergonomic components were skill-related. Robotic experts could benefit the most from the ergonomic advantages in robotic surgery. These results emphasize the need for well-structured training and well-defined ergonomics guidelines to maximize the benefits utilizing the robotic surgery.
Dagher, Rada K; McGovern, Patricia M; Dowd, Bryan E; Lundberg, Ulf
2011-10-01
To investigate the effects of total workload and other work-related factors on postpartum depression in the first 6 months after childbirth, utilizing a hybrid model of health and workforce participation. We utilized data from the Maternal Postpartum Health Study collected in 2001 from a prospective cohort of 817 employed women who delivered in three community hospitals in Minnesota. Interviewers collected data at enrollment and 5 weeks, 11 weeks, and 6 months after childbirth. The Edinburgh Postnatal Depression Scale measured postpartum depression. Independent variables included total workload (paid and unpaid work), job flexibility, supervisor and coworker support, available social support, job satisfaction, infant sleep problems, infant irritable temperament, and breastfeeding. Total average daily workload increased from 14.4 h (6.8 h of paid work; 7.1% working at 5 weeks postpartum) to 15.0 h (7.9 h of paid work; 87% working at 6 months postpartum) over the 6 months. Fixed effects regression analyses showed worse depression scores were associated with higher total workload, lower job flexibility, lower social support, an infant with sleep problems, and breastfeeding. Working mothers of reproductive years may find the study results valuable as they consider merging their work and parenting roles after childbirth. Future studies should examine the specific mechanisms through which total workload affects postpartum depressive symptoms.
Supporting Academic Workloads in Online Learning
ERIC Educational Resources Information Center
Haggerty, Carmel E.
2015-01-01
Academic workloads in online learning are influenced by many variables, the complexity of which makes it difficult to measure academic workloads in isolation. While researching issues associated with academic workloads, professional development stood out as having a substantive impact on academic workloads. Many academics in applied health degrees…
Optically powered and interrogated rotary position sensor for aircraft engine control applications
NASA Astrophysics Data System (ADS)
Spillman, W. B.; Crowne, D. H.; Woodward, D. W.
A throttle level angle (TLA) sensing system is described that utilizes a capacitance based rotary position transducer that is powered and interrogated via light from a single multimode optical fiber. The system incorporates a unique GaAs device that serves as both a power converter and optical data transmitter. Design considerations are discussed, and the fabrication and performance of the sensor system are detailed.
Influence of atomic densities on propagation property for ultrashort pulses in a two-level medium
NASA Astrophysics Data System (ADS)
Liu, Bingxin; Gong, Shangqing; Song, Xiaohong; Jin, Shiqi
2005-05-01
The influence of atomic densities on the propagation property for ultrashort pulses in a two-level atom (TLA) medium is investigated. With higher atomic densities, the self-induced transparency (SIT) cannot be recovered even for 2? ultrashort pulses. New features such as pulse splitting, red-shift and blue-shift of the corresponding spectra arise, and the component of central frequency gradually disappears.
Spectral Effects for an Ultrashort Pulse Train Propagating in a Two-Level Atom Medium
NASA Astrophysics Data System (ADS)
Liu, Bing-Xin; Gong, Shang-Qing; Song, Xiao-Hong; Li, Ru-Xin; Xu, Zhi-Zhan
2005-06-01
We investigate the spectra of a femtosecond pulse train propagating in a resonant two-level atom (TLA) medium. It is found that higher spectral components can be produced even for a 2π femtosecond pulse train. Furthermore, the spectral effects depend crucially on both the relative shift Φ and the delay time τ between the successive pulses of the femtosecond pulse train.
Marchand, Lilian; Lamy, Pierre; Bert, Valerie; Quintela-Sabaris, Celestino; Mench, Michel
2016-02-01
Foliar ionome, photosystem II activity, and leaf growth parameters of Ranunculus acris L., a potential biomonitor of trace element (TE) contamination and phytoavailability, were assessed using two riverbank soil series. R. acris was cultivated on two potted soil series obtained by mixing a TE (Cd, Cu, Pb, and Zn)-contaminated technosol with either an uncontaminated sandy riverbank soil (A) or a silty clay one slightly contaminated by TE (B). Trace elements concentrations in the soil-pore water and the leaves, leaf dry weight (DW) yield, total leaf area (TLA), specific leaf area (SLA), and photosystem II activity were measured for both soil series after a 50-day growth period. As soil contamination increased, changes in soluble TE concentrations depended on soil texture. Increase in total soil TE did not affect the leaf DW yield, the TLA, the SLA, and the photosystem II activity of R. acris over the 50-day exposure. The foliar ionome did not reflect the total and soluble TE concentrations in both soil series. Foliar ionome of R. acris was only effective to biomonitor total and soluble soil Na concentrations in both soil series and total and soluble soil Mo concentrations in the soil series B.
Cain-Hom, Carol; Splinter, Erik; van Min, Max; Simonis, Marieke; van de Heijning, Monique; Martinez, Maria; Asghari, Vida
2017-01-01
Abstract Cre/LoxP technology is widely used in the field of mouse genetics for spatial and/or temporal regulation of gene function. For Cre lines generated via pronuclear microinjection of a Cre transgene construct, the integration site is random and in most cases not known. Integration of a transgene can disrupt an endogenous gene, potentially interfering with interpretation of the phenotype. In addition, knowledge of where the transgene is integrated is important for planning of crosses between animals carrying a conditional allele and a given Cre allele in case the alleles are on the same chromosome. We have used targeted locus amplification (TLA) to efficiently map the transgene location in seven previously published Cre and CreERT2 transgenic lines. In all lines, transgene insertion was associated with structural changes of variable complexity, illustrating the importance of testing for rearrangements around the integration site. In all seven lines the exact integration site and breakpoint sequences were identified. Our methods, data and genotyping assays can be used as a resource for the mouse community and our results illustrate the power of the TLA method to not only efficiently map the integration site of any transgene, but also provide additional information regarding the transgene integration events. PMID:28053125
Rutting and Fatigue Cracking Resistance of Waste Cooking Oil Modified Trinidad Asphaltic Materials
Maharaj, Rean; Ramjattan-Harry, Vitra; Mohamed, Nazim
2015-01-01
The influence of waste cooking oil (WCO) on the performance characteristics of asphaltic materials indigenous to Trinidad, namely, Trinidad Lake Asphalt (TLA), Trinidad Petroleum Bitumen (TPB), and TLA : TPB (50 : 50) blend, was investigated to deduce the applicability of the WCO as a performance enhancer for the base asphalt. The rheological properties of complex modulus (G ∗) and phase angle (δ) were measured for modified base asphalt blends containing up to 10% WCO. The results of rheology studies demonstrated that the incremental addition of WCO to the three parent binders resulted in incremental decreases in the rutting resistance (decrease in G ∗/sinδ values) and increases in the fatigue cracking resistance (decrease in G ∗sinδ value). The fatigue cracking resistance and rutting resistance for the TLA : TPB (50 : 50) blends were between those of the blends containing pure TLA and TPB. As operating temperature increased, an increase in the resistance to fatigue cracking and a decrease in the rutting resistance were observed for all of the WCO modified asphaltic blends. This study demonstrated the capability to create customized asphalt-WCO blends to suit special applications and highlights the potential for WCO to be used as an environmentally attractive option for improving the use of Trinidad asphaltic materials. PMID:26336652
Generating Shifting Workloads to Benchmark Adaptability in Relational Database Systems
NASA Astrophysics Data System (ADS)
Rabl, Tilmann; Lang, Andreas; Hackl, Thomas; Sick, Bernhard; Kosch, Harald
A large body of research concerns the adaptability of database systems. Many commercial systems already contain autonomic processes that adapt configurations as well as data structures and data organization. Yet there is virtually no possibility for a just measurement of the quality of such optimizations. While standard benchmarks have been developed that simulate real-world database applications very precisely, none of them considers variations in workloads produced by human factors. Today’s benchmarks test the performance of database systems by measuring peak performance on homogeneous request streams. Nevertheless, in systems with user interaction access patterns are constantly shifting. We present a benchmark that simulates a web information system with interaction of large user groups. It is based on the analysis of a real online eLearning management system with 15,000 users. The benchmark considers the temporal dependency of user interaction. Main focus is to measure the adaptability of a database management system according to shifting workloads. We will give details on our design approach that uses sophisticated pattern analysis and data mining techniques.
Workload - An examination of the concept
NASA Technical Reports Server (NTRS)
Gopher, Daniel; Donchin, Emanuel
1986-01-01
The relations between task difficulty and workload and workload and performance are examined. The architecture and limitations of the central processor are discussed. Various procedures for measuring workload are described and evaluated. Consideration is given to normative and descriptive approaches; subjective, performance, and arousal measures; performance operating characteristics; and psychophysiological measures of workload.
Carayon, Pascale; Gürses, Ayşe P
2005-10-01
In this paper, we review the literature on nursing workload in intensive care units (ICUs) and its impact on patient safety and quality of working life of nurses. We then propose a conceptual framework of ICU nursing workload that defines causes, consequences and outcomes of workload. We identified four levels of nursing workload (ICU/unit level, job level, patient level, and situation level), and discuss measures associated with each of the four levels. A micro-level approach to ICU nursing workload at the situation level is proposed and recommended in order to reduce workload and mitigate its negative impact. Performance obstacles are conceptualized as causes of ICU nursing workload at the situation level.
The Workload Curve: Subjective Mental Workload.
Estes, Steven
2015-11-01
In this paper I begin looking for evidence of a subjective workload curve. Results from subjective mental workload assessments are often interpreted linearly. However, I hypothesized that ratings of subjective mental workload increase nonlinearly with unitary increases in working memory load. Two studies were conducted. In the first, the participant provided ratings of the mental difficulty of a series of digit span recall tasks. In the second study, participants provided ratings of mental difficulty associated with recall of visual patterns. The results of the second study were then examined using a mathematical model of working memory. An S curve, predicted a priori, was found in the results of both the digit span and visual pattern studies. A mathematical model showed a tight fit between workload ratings and levels of working memory activation. This effort provides good initial evidence for the existence of a workload curve. The results support further study in applied settings and other facets of workload (e.g., temporal workload). Measures of subjective workload are used across a wide variety of domains and applications. These results bear on their interpretation, particularly as they relate to workload thresholds. © 2015, Human Factors and Ergonomics Society.
Chiorri, Carlo; Garbarino, Sergio; Bracco, Fabrizio; Magnavita, Nicola
2015-01-01
Previous research has suggested that personality traits of the Five Factor Model play a role in worker's response to workload. The aim of this study was to investigate the association of personality traits of first responders with their perceived workload in real-life tasks. A flying column of 269 police officers completed a measure of subjective workload (NASA-Task Load Index) after intervention tasks in a major public event. Officers' scores on a measure of Five Factor Model personality traits were obtained from archival data. Linear Mixed Modeling was used to test the direct and interaction effects of personality traits on workload scores once controlling for background variables, task type and workload source (mental, temporal and physical demand of the task, perceived effort, dissatisfaction for the performance and frustration due to the task). All personality traits except extraversion significantly interacted at least with one workload source. Perceived workload in flying column police officers appears to be the result of their personality characteristics interacting with the workload source. The implications of these results for the development of support measures aimed at reducing the impact of workload in this category of workers are discussed. PMID:26640456
Assessing Continuous Operator Workload With a Hybrid Scaffolded Neuroergonomic Modeling Approach.
Borghetti, Brett J; Giametta, Joseph J; Rusnock, Christina F
2017-02-01
We aimed to predict operator workload from neurological data using statistical learning methods to fit neurological-to-state-assessment models. Adaptive systems require real-time mental workload assessment to perform dynamic task allocations or operator augmentation as workload issues arise. Neuroergonomic measures have great potential for informing adaptive systems, and we combine these measures with models of task demand as well as information about critical events and performance to clarify the inherent ambiguity of interpretation. We use machine learning algorithms on electroencephalogram (EEG) input to infer operator workload based upon Improved Performance Research Integration Tool workload model estimates. Cross-participant models predict workload of other participants, statistically distinguishing between 62% of the workload changes. Machine learning models trained from Monte Carlo resampled workload profiles can be used in place of deterministic workload profiles for cross-participant modeling without incurring a significant decrease in machine learning model performance, suggesting that stochastic models can be used when limited training data are available. We employed a novel temporary scaffold of simulation-generated workload profile truth data during the model-fitting process. A continuous workload profile serves as the target to train our statistical machine learning models. Once trained, the workload profile scaffolding is removed and the trained model is used directly on neurophysiological data in future operator state assessments. These modeling techniques demonstrate how to use neuroergonomic methods to develop operator state assessments, which can be employed in adaptive systems.
Yurko, Yuliya Y; Scerbo, Mark W; Prabhu, Ajita S; Acker, Christina E; Stefanidis, Dimitrios
2010-10-01
Increased workload during task performance may increase fatigue and facilitate errors. The National Aeronautics and Space Administration-Task Load Index (NASA-TLX) is a previously validated tool for workload self-assessment. We assessed the relationship of workload and performance during simulator training on a complex laparoscopic task. NASA-TLX workload data from three separate trials were analyzed. All participants were novices (n = 28), followed the same curriculum on the fundamentals of laparoscopic surgery suturing model, and were tested in the animal operating room (OR) on a Nissen fundoplication model after training. Performance and workload scores were recorded at baseline, after proficiency achievement, and during the test. Performance, NASA-TLX scores, and inadvertent injuries during the test were analyzed and compared. Workload scores declined during training and mirrored performance changes. NASA-TLX scores correlated significantly with performance scores (r = -0.5, P < 0.001). Participants with higher workload scores caused more inadvertent injuries to adjacent structures in the OR (r = 0.38, P < 0.05). Increased mental and physical workload scores at baseline correlated with higher workload scores in the OR (r = 0.52-0.82; P < 0.05) and more inadvertent injuries (r = 0.52, P < 0.01). Increased workload is associated with inferior task performance and higher likelihood of errors. The NASA-TLX questionnaire accurately reflects workload changes during simulator training and may identify individuals more likely to experience high workload and more prone to errors during skill transfer to the clinical environment.
Nuclear physics for materials technology
NASA Astrophysics Data System (ADS)
Conlon, T. W.
1987-04-01
Although particle accelerators have traditionally been used to further our knowledge of nuclear physics, the last decade or so has seen a rapid growth of their involvement in materials technology — both to modify materials and to provide analytical information at the atomic level that cannot be obtained in other ways. The deployment of ion beams in these areas has occurred in three phases: first the exploitation of keV ion beams (in ion implantation and SIMS) then MeV light ion beams (using RBS, NRA, PIXE analysis and TLA) and currently MeV heavy ion beams, together with the associated fast recoil atoms and nuclei that they produce in interactions with materials. This trend has been accompanied by the gradual assimilation of methods such as energy analysis, microbeam focussing, particle identification, time of flight and coincidence techniques, etc., which were first developed for experimental nuclear physics use. Current examples of developments in the MeV range relevant to phases 2 and 3 are given.
Xiao, Yuanmei; Li, Weijuan; Ren, Qingfeng; Ren, Xiaohui; Wang, Zhiming; Wang, Mianzhen; Lan, Yajia
2015-01-01
To investigate the distribution and main influential factors of mental workload of middle school teachers in Nanchang City. A total of 504 middle school teachers were sampled by random cluster sampling from middle schools in Nanchang City, and the mental workload level was assessed with National Aeronautics and Space Administration-Task Load Index (NASA-TLX) which was verified in reliability and validity. The mental workload scores of middle school teachers in Nanchang was approximately normal distribution. The mental workload level of middle school teachers aged 31 -35 years old was the highest. For those no more than 35 years old, there was positive correlation between mental workload and age (r = 0.146, P < 0.05). For those more than 35 years old, the levels of their mental workload had no statistically significant difference. There was a negative correlation between mental workload and educational level(r = -0.172, P < 0.05). The middle school teachers with lower educational level seemed to have a higher mental workload (P < 0.01). The longer a middle school teacher worked per day, the higher the mental workload was. Working hours per day was the most influential factor on mental workload in all influential factors (P < 0.001). Mental workload of middle school teachers was closely related to age, educational level and work hours per day. Working hours per day was the important risk factor of mental workload. Reducing working hours per day, especially reducing it to be no more than 8 hours per day, may be a significant and useful approach alleviating mental workload of middle school teachers in Nanchang City.
Injury risk-workload associations in NCAA American college football.
Sampson, J A; Murray, A; Williams, S; Halseth, T; Hanisch, J; Golden, G; Fullagar, H H K
2018-05-22
To determine injury risk-workload associations in collegiate American Football. Retrospective analysis. Workload and injury data was recorded from 52 players during a full NCAA football season. Acute, chronic, and a range of acute:chronic workload ratios (ACWR: 7:14, 7:21 and 7:28 day) calculated using rolling and exponentially weighted moving averages (EWMA) were plotted against non-contact injuries (regardless of time lost or not) sustained within 3- and 7-days. Injury risks were also determined relative to position and experience. 105 non-contact injuries (18 game- and 87 training-related) were observed with almost 40% sustained during the pre-season. 7-21 day EWMA ACWR's with a 3-day injury lag were most closely associated with injury (R 2 =0.54). Relative injury risks were >3× greater with high compared to moderate and low ratios and magnified when combined with low 21-day chronic workloads (injury probability=92.1%). Injury risks were similar across positions. 'Juniors' presented likely and possibly increased overall injury risk compared to 'Freshman' (RR: 1.94, CI 1.07-3.52) and 'Seniors' (RR: 1.7, CI 0.92-3.14), yet no specific ACWR - experience or - position interactions were identified. High injury rates during college football pre-season training may be associated with high acute loads. In-season injury risks were greatest with high ACWR and evident even when including (more common and less serious) non-time loss injuries. Substantially increased injury risks when low 21-day chronic workloads and concurrently high EWMA ACWR highlights the importance of load management for individuals with chronic game- (non-involved on game day) and or training (following injury) absences. Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Ligda, Sarah V.; Dao, Arik-Quang V.; Vu, Kim-Phuong; Strybel, Thomas Z.; Battiste, Vernol; Johnson, Walter W.
2010-01-01
Pilot workload was examined during simulated flights requiring flight deck-based merging and spacing while avoiding weather. Pilots used flight deck tools to avoid convective weather and space behind a lead aircraft during an arrival into Louisville International airport. Three conflict avoidance management concepts were studied: pilot, controller or automation primarily responsible. A modified Air Traffic Workload Input Technique (ATWIT) metric showed highest workload during the approach phase of flight and lowest during the en-route phase of flight (before deviating for weather). In general, the modified ATWIT was shown to be a valid and reliable workload measure, providing more detailed information than post-run subjective workload metrics. The trend across multiple workload metrics revealed lowest workload when pilots had both conflict alerting and responsibility of the three concepts, while all objective and subjective measures showed highest workload when pilots had no conflict alerting or responsibility. This suggests that pilot workload was not tied primarily to responsibility for resolving conflicts, but to gaining and/or maintaining situation awareness when conflict alerting is unavailable.
Liu, Zhian; Zhang, Ming; Xu, Gongcheng; Huo, Congcong; Tan, Qitao; Li, Zengyong; Yuan, Quan
2017-01-01
Driving a vehicle is a complex activity that requires high-level brain functions. This study aimed to assess the change in effective connectivity (EC) between the prefrontal cortex (PFC), motor-related areas (MA) and vision-related areas (VA) in the brain network among the resting, simple-driving and car-following states. Twelve young male right-handed adults were recruited to participate in an actual driving experiment. The brain delta [HbO2] signals were continuously recorded using functional near infrared spectroscopy (fNIRS) instruments. The conditional Granger causality (GC) analysis, which is a data-driven method that can explore the causal interactions among different brain areas, was performed to evaluate the EC. The results demonstrated that the hemodynamic activity level of the brain increased with an increase in the cognitive workload. The connection strength among PFC, MA and VA increased from the resting state to the simple-driving state, whereas the connection strength relatively decreased during the car-following task. The PFC in EC appeared as the causal target, while the MA and VA appeared as the causal sources. However, l-MA turned into causal targets with the subtask of car-following. These findings indicate that the hemodynamic activity level of the cerebral cortex increases linearly with increasing cognitive workload. The EC of the brain network can be strengthened by a cognitive workload, but also can be weakened by a superfluous cognitive workload such as driving with subtasks. PMID:29163083
Sense of coherence modifies the effect of overtime work on mental health.
Ohta, Masanori; Higuchi, Yoshiyuki; Yamato, Hiroshi; Kumashiro, Masaharu; Sugimura, Hisamichi
2015-01-01
In the occupational health field, it is important to know how workload influences mental health. Overtime work and job strain appear to affect the mental health status of workers. Sense of coherence (SOC) may mediate the relationship between work stress and mental health. Since SOC represents a personal ability to manage psychological stressors, we hypothesized that a strong SOC would modify the adverse effect of an objective measure of overtime work on mental health. A total of 1,558 Japanese workers employed in an information technology company were asked to complete a 3-item SOC Questionnaire and 28-item General Health Questionnaire (GHQ) to assess mental health status. Workload was assessed by the actual amount of overtime work hours recorded by the company. Multiple regression analysis revealed a main effect of overtime work (β=0.08, p=0.0003) and SOC scores (β=0.41, p <0.0001) on GHQ scores. There was a tendency toward interaction between overtime work and SOC scores (β=0.05, p=0.051). Simple slope analysis supported this association (-1 SD below the mean, simple slope=0.04, SE=0.01, p < 0.0001; +1 SD above the mean, simple slope=0.01, SE=0.01, p=0.188). These results suggest that SOC buffers the mental health impacts of workload as measured by an objective index of overtime work, and should be considered when assessing the effects of workload on mental health.
Relationship between workload and mind-wandering in simulated driving
2017-01-01
Mental workload and mind-wandering are highly related to driving safety. This study investigated the relationship between mental workload and mind-wandering while driving. Participants (N = 40) were asked to perform a car following task in driving simulator, and report whether they had experienced mind-wandering upon hearing a tone. After driving, participants reported their workload using the NASA-Task Load Index (TLX). Results revealed an interaction between workload and mind-wandering in two different perspectives. First, there was a negative correlation between workload and mind-wandering (r = -0.459, p < 0.01) for different individuals. Second, from temporal perspective workload and mind-wandering frequency increased significantly over task time and were positively correlated. Together, these findings contribute to understanding the roles of workload and mind-wandering in driving. PMID:28467513
Defining the subjective experience of workload
NASA Technical Reports Server (NTRS)
Hart, S. G.; Childress, M. E.; Bortolussi, M.
1981-01-01
Flight scenarios that represent different types and levels of pilot workload are needed in order to conduct research about, and develop measures of, pilot workload. In order to be useful, however, the workload associated with such scenarios and the component tasks must be determined independently. An initial study designed to provide such information was conducted by asking a panel of general aviation pilots to evaluate flight-related tasks for the overall, perceptual, physical, and cognitive workload they impose. These ratings will provide the nucleus for a data base of flight-related primary tasks that have been independently rated for workload to use in workload assessment research.
Effects of workload preview on task scheduling during simulated instrument flight.
Andre, A D; Heers, S T; Cashion, P A
1995-01-01
Our study examined pilot scheduling behavior in the context of simulated instrument flight. Over the course of the flight, pilots flew along specified routes while scheduling and performing several flight-related secondary tasks. The first phase of flight was flown under low-workload conditions, whereas the second phase of flight was flown under high-workload conditions in the form of increased turbulence and a disorganized instrument layout. Six pilots were randomly assigned to each of three workload preview groups. Subjects in the no-preview group were not given preview of the increased-workload conditions. Subjects in the declarative preview group were verbally informed of the nature of the flight workload manipulation but did not receive any practice under the high-workload conditions. Subjects in the procedural preview group received the same instructions as the declarative preview group but also flew half of the practice flight under the high-workload conditions. The results show that workload preview fostered efficient scheduling strategies. Specifically, those pilots with either declarative or procedural preview of future workload demands adopted an efficient strategy of scheduling more of the difficult secondary tasks during the low-workload phase of flight. However, those pilots given a procedural preview showed the greatest benefits in overall flight performance.
Workload of Team Leaders and Team Members During a Simulated Sepsis Scenario.
Tofil, Nancy M; Lin, Yiqun; Zhong, John; Peterson, Dawn Taylor; White, Marjorie Lee; Grant, Vincent; Grant, David J; Gottesman, Ronald; Sudikoff, Stephanie N; Adler, Mark; Marohn, Kimberly; Davidson, Jennifer; Cheng, Adam
2017-09-01
Crisis resource management principles dictate appropriate distribution of mental and/or physical workload so as not to overwhelm any one team member. Workload during pediatric emergencies is not well studied. The National Aeronautics and Space Administration-Task Load Index is a multidimensional tool designed to assess workload validated in multiple settings. Low workload is defined as less than 40, moderate 40-60, and greater than 60 signify high workloads. Our hypothesis is that workload among both team leaders and team members is moderate to high during a simulated pediatric sepsis scenario and that team leaders would have a higher workload than team members. Multicenter observational study. Nine pediatric simulation centers (five United States, three Canada, and one United Kingdom). Team leaders and team members during a 12-minute pediatric sepsis scenario. National Aeronautics and Space Administration-Task Load Index. One hundred twenty-seven teams were recruited from nine sites. One hundred twenty-seven team leaders and 253 team members completed the National Aeronautics and Space Administration-Task Load Index. Team leader had significantly higher overall workload than team member (51 ± 11 vs 44 ± 13; p < 0.01). Team leader had higher workloads in all subcategories except in performance where the values were equal and in physical demand where team members were higher than team leaders (29 ± 22 vs 18 ± 16; p < 0.01). The highest category for each group was mental 73 ± 13 for team leader and 60 ± 20 for team member. For team leader, two categories, mental (73 ± 17) and effort (66 ± 16), were high workload, most domains for team member were moderate workload levels. Team leader and team member are under moderate workloads during a pediatric sepsis scenario with team leader under high workloads (> 60) in the mental demand and effort subscales. Team leader average significantly higher workloads. Consideration of decreasing team leader responsibilities may improve team workload distribution.
Mental workload measurement in operator control room using NASA-TLX
NASA Astrophysics Data System (ADS)
Sugarindra, M.; Suryoputro, M. R.; Permana, A. I.
2017-12-01
The workload, encountered a combination of physical workload and mental workload, is a consequence of the activities for workers. Central control room is one department in the oil processing company, employees tasked with monitoring the processing unit for 24 hours nonstop with a combination of 3 shifts in 8 hours. NASA-TLX (NASA Task Load Index) is one of the subjective mental workload measurement using six factors, namely the Mental demand (MD), Physical demand (PD), Temporal demand (TD), Performance (OP), Effort (EF), frustration levels (FR). Measurement of a subjective mental workload most widely used because it has a high degree of validity. Based on the calculation of the mental workload, there at 5 units (DTU, NPU, HTU, DIST and OPS) at the control chamber (94; 83.33; 94.67; 81, 33 and 94.67 respectively) that categorize as very high mental workload. The high level of mental workload on the operator in the Central Control Room is a requirement to have high accuracy, alertness and can make decisions quickly
Preliminary study of the pilot's workload during emergency procedures in helicopters air operations.
Bezerra, Flávio G V; Ribeiro, Selma L O
2012-01-01
Military air operations and law enforcement operations in helicopters are examples of activities that require high performance of the operator. This article aimed at presenting a preliminary analysis of data obtained in the initial study in order to validate the instruments and the research protocol that focuses on the analysis of the workload imposed on helicopter pilots in emergency situations. The research was conducted in an environment of real flight training and used the NASA-TLX Scale to assess the workload and an interview guide to obtain reports on the main tasks performed. Preliminary data obtained is related to the participation of 10 (ten) volunteer pilots with experience in different types of helicopters. Four scenarios involving helicopter emergency procedures of HB-350 "Squirrel" were outlined. For this article, the analysis used only the data regarding the Physical and Mental Demands of the NASA-TLX Scale. Preliminarily, the results indicate that the "time pressure" as a factor contributing to increase mental requirement in emergency situations in flight, and that this increase was reflected in the request of mental processes such as: identification of the breakdown, attention and monitoring parameters. Future steps include extending the sample and adding physiological tools to better understand the effects of these types of emergencies on pilot performance and flight safety.
[Study on mental workload of teachers in primary schools].
Xiao, Yuan-mei; Wang, Zhi-ming; Wang, Mian-zhen; Lan, Ya-jia; Fan, Guang-qin; Feng, Chang
2011-12-01
To investigate the distribution characteristics and influencing factors of mental workload of teachers in primary schools. National Aeronautics and Space Administration-Task Load Index (NASA-TLX) was used to assess the mental workload levels for 397 teachers of primary schools in a city. The mental workload (64.34+10.56) of female teachers was significantly higher than that (61.73+ 9.77) of male teachers (P<0.05). The mental workload (65.66+10.42) of "-35" years old group was the highest. When age of teachers was younger than 35 years old, there was a positive correlation between the mental workload and age (r=0.146, P<0.05). When age of teachers was older than 35 years old, there was a negative correlation between the mental workload and age (r=-0.190, P<0.05). The teachers with higher education level felt higher mental workload (unstandardized coefficients B=1.524, standardized coefficients /=0.111, P<0.05). There was a positive correlation between the mental workload and working hours per day (unstandardized coefficients B =4.659, standardized coefficients/3 =0.223, P<0.001). Mental workload of the teachers in primary schools is closely related to age, educational level and work hours per day. Work hours per day is an important risk factor for mental workload. Reducing work hours per day (8 hours) is an effective measure of alleviating the mental workload of teachers in primary schools.
Using the NASA Task Load Index to Assess Workload in Electronic Medical Records.
Hudson, Darren; Kushniruk, Andre W; Borycki, Elizabeth M
2015-01-01
Electronic medical records (EMRs) has been expected to decrease health professional workload. The NASA Task Load Index has become an important tool for assessing workload in many domains. However, its application in assessing the impact of an EMR on nurse's workload has remained to be explored. In this paper we report the results of a study of workload and we explore the utility of applying the NASA Task Load Index to assess impact of an EMR at the end of its lifecycle on nurses' workload. It was found that mental and temporal demands were the most responsible for the workload. Further work along these lines is recommended.
Mental workload prediction based on attentional resource allocation and information processing.
Xiao, Xu; Wanyan, Xiaoru; Zhuang, Damin
2015-01-01
Mental workload is an important component in complex human-machine systems. The limited applicability of empirical workload measures produces the need for workload modeling and prediction methods. In the present study, a mental workload prediction model is built on the basis of attentional resource allocation and information processing to ensure pilots' accuracy and speed in understanding large amounts of flight information on the cockpit display interface. Validation with an empirical study of an abnormal attitude recovery task showed that this model's prediction of mental workload highly correlated with experimental results. This mental workload prediction model provides a new tool for optimizing human factors interface design and reducing human errors.
Measuring workload in collaborative contexts: trait versus state perspectives.
Helton, William S; Funke, Gregory J; Knott, Benjamin A
2014-03-01
In the present study, we explored the state versus trait aspects of measures of task and team workload in a disaster simulation. There is often a need to assess workload in both individual and collaborative settings. Researchers in this field often use the NASATask Load Index (NASA-TLX) as a global measure of workload by aggregating the NASA-TLX's component items. Using this practice, one may overlook the distinction between traits and states. Fifteen dyadic teams (11 inexperienced, 4 experienced) completed five sessions of a tsunami disaster simulator. After every session, individuals completed a modified version of the NASA-TLX that included team workload measures.We then examined the workload items by using a between-subjects and within-subjects perspective. Between-subjects and within-subjects correlations among the items indicated the workload items are more independent within subjects (as states) than between subjects (as traits). Correlations between the workload items and simulation performance were also different at the trait and state levels. Workload may behave differently at trait (between-subjects) and state (within-subjects) levels. Researchers interested in workload measurement as a state should take a within-subjects perspective in their analyses.
Novel method of measuring the mental workload of anaesthetists during clinical practice.
Byrne, A J; Oliver, M; Bodger, O; Barnett, W A; Williams, D; Jones, H; Murphy, A
2010-12-01
Cognitive overload has been recognized as a significant cause of error in industries such as aviation and measuring mental workload has become a key method of improving safety. The aim of this study was to pilot the use of a new method of measuring mental workload in the operating theatre using a previously published methodology. The mental workload of the anaesthetists was assessed by measuring their response times to a wireless vibrotactile device and the NASA TLX subjective workload score during routine surgical procedures. Primary task workload was inferred from the phase of anaesthesia. Significantly increased response time was associated with the induction phase of anaesthesia compared with maintenance/emergence, non-consultant grade, and during more complex cases. Increased response was also associated with self-reported mental load, physical load, and frustration. These findings are consistent with periods of increased mental workload and with the findings of other studies using similar techniques. These findings confirm the importance of mental workload to the performance of anaesthetists and suggest that increased mental workload is likely to be a common problem in clinical practice. Although further studies are required, the method described may be useful for the measurement of the mental workload of anaesthetists.
Assessment of mental workload and academic motivation in medical students.
Atalay, Kumru Didem; Can, Gulin Feryal; Erdem, Saban Remzi; Muderrisoglu, Ibrahim Haldun
2016-05-01
To investigate the level of correlation and direction of linearity between academic motivation and subjective workload. The study was conducted at Baskent University School of Medicine, Ankara, Turkey, from December 2013 to February 2014, and comprised Phase 5 Phase 6 medical students. Subjective workload level was determined by using National Aeronautics and Space Administration Task Load Index scale that was adapted to Turkish. Academic motivation values were obtained with the help of Academic Motivation Scale university form. SPSS 17 was used for statistical analysis. Of the total 105 subjects, 65(62%) students were in Phase 5 and 40(38%) were in Phase 6. Of the Phase 5 students, 18(27.7%) were boys and 47(72.3%) were girls, while of the Phase 6 students, 16(40%) were boys and 24(60%) were girls. There were significant differences in Phase 5 and Phase 6 students for mental effort (p=0.00) and physical effort (p=0.00). The highest correlation in Phase 5 was between mental effort and intrinsic motivation (r=0.343). For Phase 6, highest correlation was between effort and amotivation (r= -0.375). Subjective workload affected academic motivation in medical students.
Resources–tasks imbalance: Experiences of nurses from factors influencing workload to increase
Khademi, Mojgan; Mohammadi, Easa; Vanaki, Zohreh
2015-01-01
Background: While nursing workload is a worldwide challenge, less attention has been given to the determining factors. Understanding these factors is important and could help nursing managers to provide suitable working environment and to manage the adverse outcomes of nursing workload. The aim of this study was to discover nurses’ experiences of determinant factors of their workload. Materials and Methods: In this qualitative study, the participants included 15 nurses working in two hospitals in Tehran, Iran. The data were collected through 26 unstructured interviews and were analyzed using conventional content analysis. The rigor has been guaranteed with prolonged engagement, maximum variance sampling, member check, and audit trail. Results: Resource–task imbalance was the main theme of nurses’ experiences. It means that there was an imbalance between necessary elements to meet patients’ needs in comparison with expectation and responsibility. Resource–task imbalance included lack of resource, assignment without preparation, assigning non-care tasks, and patients’ and families’ needs/expectations. Conclusions: A deep and comprehensive imbalance between recourses and tasks and expectations has been perceived by the participants to be the main source of work overload. Paying more attention to resource allocation, education of quality workforce, and job description by managers is necessary. PMID:26257804
Brain Interaction during Cooperation: Evaluating Local Properties of Multiple-Brain Network.
Sciaraffa, Nicolina; Borghini, Gianluca; Aricò, Pietro; Di Flumeri, Gianluca; Colosimo, Alfredo; Bezerianos, Anastasios; Thakor, Nitish V; Babiloni, Fabio
2017-07-21
Subjects' interaction is the core of most human activities. This is the reason why a lack of coordination is often the cause of missing goals, more than individual failure. While there are different subjective and objective measures to assess the level of mental effort required by subjects while facing a situation that is getting harder, that is, mental workload, to define an objective measure based on how and if team members are interacting is not so straightforward. In this study, behavioral, subjective and synchronized electroencephalographic data were collected from couples involved in a cooperative task to describe the relationship between task difficulty and team coordination, in the sense of interaction aimed at cooperatively performing the assignment. Multiple-brain connectivity analysis provided information about the whole interacting system. The results showed that averaged local properties of a brain network were affected by task difficulty. In particular, strength changed significantly with task difficulty and clustering coefficients strongly correlated with the workload itself. In particular, a higher workload corresponded to lower clustering values over the central and parietal brain areas. Such results has been interpreted as less efficient organization of the network when the subjects' activities, due to high workload tendencies, were less coordinated.
Measurement-based analysis of error latency. [in computer operating system
NASA Technical Reports Server (NTRS)
Chillarege, Ram; Iyer, Ravishankar K.
1987-01-01
This paper demonstrates a practical methodology for the study of error latency under a real workload. The method is illustrated with sampled data on the physical memory activity, gathered by hardware instrumentation on a VAX 11/780 during the normal workload cycle of the installation. These data are used to simulate fault occurrence and to reconstruct the error discovery process in the system. The technique provides a means to study the system under different workloads and for multiple days. An approach to determine the percentage of undiscovered errors is also developed and a verification of the entire methodology is performed. This study finds that the mean error latency, in the memory containing the operating system, varies by a factor of 10 to 1 (in hours) between the low and high workloads. It is found that of all errors occurring within a day, 70 percent are detected in the same day, 82 percent within the following day, and 91 percent within the third day. The increase in failure rate due to latency is not so much a function of remaining errors but is dependent on whether or not there is a latent error.
Workload and non-contact injury incidence in elite football players competing in European leagues.
Delecroix, Barthelemy; McCall, Alan; Dawson, Brian; Berthoin, Serge; Dupont, Gregory
2018-06-02
The aim of this study was to analyse the relationship between absolute and acute:chronic workload ratios and non-contact injury incidence in professional football players and to assess their predictive ability. Elite football players (n = 130) from five teams competing in European domestic and confederation level competitions were followed during one full competitive season. Non-contact injuries were recorded and using session rate of perceived exertion (s-RPE) internal absolute workload and acute:chronic (A:C) workload ratios (4-weeks, 3-weeks, 2-weeks and week-to-week) were calculated using a rolling days method. The relative risk (RR) of non-contact injury was increased (RR = 1.59, CI95%: 1.18-2.15) when a cumulative 4-week absolute workload was greater than 10629 arbitrary units (AU) in comparison with a workload between 3745 and 10628 AU. When the 3-week absolute workload was more than 8319 AU versus between 2822 and 8318 AU injury risk was also increased (RR= 1.46, CI95% 1.08-1.98). Injury incidence was higher when the 4-week A:C ratio was <0.85 versus >0.85 (RR = 1.31, CI95%: 1.02-1.70) and with a 3-week A:C ratio >1.30 versus <1.30 (RR = 1.37, CI95%: 1.05-1.77). Importantly, none of the A:C workload combinations showed high sensitivity or specificity. In elite European footballers, using internal workload (sRPE) revealed that cumulative workloads over 3 and 4 weeks were associated with injury incidence. Additionally, A:C workloads, using combinations of 2, 3 and 4 weeks as the C workloads were also associated with increased injury risk. No A:C workload combination was appropriate to predict injury.
Closed-loop, pilot/vehicle analysis of the approach and landing task
NASA Technical Reports Server (NTRS)
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.
Combining Quick-Turnaround and Batch Workloads at Scale
NASA Technical Reports Server (NTRS)
Matthews, Gregory A.
2012-01-01
NAS uses PBS Professional to schedule and manage the workload on Pleiades, an 11,000+ node 1B cluster. At this scale the user experience for quick-turnaround jobs can degrade, which led NAS initially to set up two separate PBS servers, each dedicated to a particular workload. Recently we have employed PBS hooks and scheduler modifications to merge these workloads together under one PBS server, delivering sub-1-minute start times for the quick-turnaround workload, and enabling dynamic management of the resources set aside for that workload.
Common mental disorders among civil aviation pilots.
Feijó, Denise; Luiz, Ronir Raggio; Camara, Volney Magalhães
2012-05-01
The purpose of this study was to estimate the prevalence of suspected cases of common mental disorders (CMD) on Brazilian civil aviation pilots and to investigate associations between CMD, demographics, and labor variables. A quantitative cross-sectional study was conducted on 807 working pilots between October 2009 and October 2010 using a self-administered questionnaire to obtain sociodemographic data and information about workload. CMD prevalence was estimated with the Self-Reporting Questionnaire-20 items (SRQ-20). Multiple logistic regression was used in statistical data analyses. The overall prevalence of CMD was 6.7% with the cutoff point of 8 used in this study, i.e., scores greater than or equal to 8 in SRQ-20 define positive cases. Using alternative cutoffs, the prevalence was 9.2% (cut off point 7) or 12% (cutoff point 6). Among the individuals who did not exercise, 10.2% presented suspected CMD. Among those with a heavy workload, 23.7% presented scores indicating suspected CMD. Only variables relating to workload and the practice of physical activity were significantly correlated with the estimate of CMD after multivariate analysis. Regular physical exercise afforded a possible protective effect against suspected cases of CMD, while there was a higher prevalence of suspected cases among subjects with heavy workloads. The inclusion of the topic of mental health among the targets and priorities of civil aviation in Brazil is imperative. Addressing issues such as the regular practice of physical activity and workload can contribute to achieving a better balance between flight safety and productivity.
Preliminary Investigation of Workload on Intrastate Bus Traffic Controllers
NASA Astrophysics Data System (ADS)
Yen Bin, Teo; Azlis-Sani, Jalil; Nur Annuar Mohd Yunos, Muhammad; Ismail, S. M. Sabri S. M.; Tajedi, Noor Aqilah Ahmad
2016-11-01
The daily routine of bus traffic controller which involves high mental processes would have a direct impact on the level of workload. To date, the level of workload on the bus traffic controllers in Malaysia is relatively unknown. Excessive workload on bus traffic controllers would affect the control and efficiency of the system. This paper served to study the workload on bus traffic controllers and justify the needs to conduct further detailed research on this field. The objectives of this research are to identify the level of workload on the intrastate bus traffic controllers. Based on the results, recommendations will be proposed for improvements and future studies. The level of workload for the bus traffic controllers is quantified using questionnaire adapted from NASA TLX. Interview sessions were conducted for validation of workload. Sixteen respondents were involved and it was found that the average level of workload based on NASA TLX was 6.91. It was found that workload is not affected by gender and marital status. This study also showed that the level of workload and working experience of bus traffic controllers has a strong positive linear relationship. This study would serve as a guidance and reference related to this field. Since this study is a preliminary investigation, further detailed studies could be conducted to obtain a better comprehension regarding the bus traffic controllers.
Mission control of multiple unmanned aerial vehicles: a workload analysis.
Dixon, Stephen R; Wickens, Christopher D; Chang, Dervon
2005-01-01
With unmanned aerial vehicles (UAVs), 36 licensed pilots flew both single-UAV and dual-UAV simulated military missions. Pilots were required to navigate each UAV through a series of mission legs in one of the following three conditions: a baseline condition, an auditory autoalert condition, and an autopilot condition. Pilots were responsible for (a) mission completion, (b) target search, and (c) systems monitoring. Results revealed that both the autoalert and the autopilot automation improved overall performance by reducing task interference and alleviating workload. The autoalert system benefited performance both in the automated task and mission completion task, whereas the autopilot system benefited performance in the automated task, the mission completion task, and the target search task. Practical implications for the study include the suggestion that reliable automation can help alleviate task interference and reduce workload, thereby allowing pilots to better handle concurrent tasks during single- and multiple-UAV flight control.
Monitoring and Managing Fatigue in Basketball
Edwards, Toby; Spiteri, Tania; Piggott, Benjamin; Bonhotal, Joshua; Joyce, Christopher
2018-01-01
The sport of basketball exposes athletes to frequent high intensity movements including sprinting, jumping, accelerations, decelerations and changes of direction during training and competition which can lead to acute and accumulated chronic fatigue. Fatigue may affect the ability of the athlete to perform over the course of a lengthy season. The ability of practitioners to quantify the workload and subsequent fatigue in basketball athletes in order to monitor and manage fatigue levels may be beneficial in maintaining high levels of performance and preventing unfavorable physical and physiological training adaptations. There is currently limited research quantifying training or competition workload outside of time motion analysis in basketball. In addition, systematic research investigating methods to monitor and manage athlete fatigue in basketball throughout a season is scarce. To effectively optimize and maintain peak training and playing performance throughout a basketball season, potential workload and fatigue monitoring strategies need to be discussed. PMID:29910323
POPCORN: a Supervisory Control Simulation for Workload and Performance Research
NASA Technical Reports Server (NTRS)
Hart, S. G.; Battiste, V.; Lester, P. T.
1984-01-01
A multi-task simulation of a semi-automatic supervisory control system was developed to provide an environment in which training, operator strategy development, failure detection and resolution, levels of automation, and operator workload can be investigated. The goal was to develop a well-defined, but realistically complex, task that would lend itself to model-based analysis. The name of the task (POPCORN) reflects the visual display that depicts different task elements milling around waiting to be released and pop out to be performed. The operator's task was to complete each of 100 task elements that ere represented by different symbols, by selecting a target task and entering the desired a command. The simulated automatic system then completed the selected function automatically. Highly significant differences in performance, strategy, and rated workload were found as a function of all experimental manipulations (except reward/penalty).
FMP study of pilot workload. Qualification of workload via instrument scan
NASA Technical Reports Server (NTRS)
Tolel, J. R.; Vivaudou, M.; Harris, R. L., Sr.; Ephrath, A.
1982-01-01
Various methods of measuring a pilot's mental workload are discussed. Scanning the various flight instruments with good scan pattern and other verbal tasks during instrument landings is given special attention for measuring pilot workload.
Mental workload measurement: Event-related potentials and ratings of workload and fatigue
NASA Technical Reports Server (NTRS)
Biferno, M. A.
1985-01-01
Event-related potentials were elicited when a digitized word representing a pilot's call-sign was presented. This auditory probe was presented during 27 workload conditions in a 3x3x3 design where the following variables were manipulated: short-term load, tracking task difficulty, and time-on-task. Ratings of workload and fatigue were obtained between each trial of a 2.5-hour test. The data of each subject were analyzed individually to determine whether significant correlations existed between subjective ratings and ERP component measures. Results indicated that a significant number of subjects had positive correlations between: (1) ratings of workload and P300 amplitude, (2) ratings of workload and N400 amplitude, and (3) ratings of fatigue and P300 amplitude. These data are the first to show correlations between ratings of workload or fatigue and ERP components thereby reinforcing their validity as measures of mental workload and fatigue.
NASA Technical Reports Server (NTRS)
Hancock, P. A.; Robinson, M. A.
1989-01-01
The present experiment examined the influence of several task-related factors on tracking performance and concomitant workload. The manipulated factors included tracking order, the presence or absence of knowledge of performance, and the control device. Summed root mean square error (rmse) and perceived workload were measured at the termination of each trial. Perceived workload was measured using the NASA Task Load Index (TLX) and the Subjective Workload Assessment Technique (SWAT). Results indicated a large and expected effect for track order on both performance and the perception of load. In general, trackball input was more accurate and judged for lower load than input using a mouse. The presence or absence of knowledge of performance had little effect on either performance or workload. There were a number of interactions between factors shown in performance that were mirrored by perceived workload scores. Results from each workload scale were equivalent in terms of sensitivity to task manipulations. The pattern of results affirm the utility of these workload measures in assessing the imposed load of multiple task-related variables.
A workload model and measures for computer performance evaluation
NASA Technical Reports Server (NTRS)
Kerner, H.; Kuemmerle, K.
1972-01-01
A generalized workload definition is presented which constructs measurable workloads of unit size from workload elements, called elementary processes. An elementary process makes almost exclusive use of one of the processors, CPU, I/O processor, etc., and is measured by the cost of its execution. Various kinds of user programs can be simulated by quantitative composition of elementary processes into a type. The character of the type is defined by the weights of its elementary processes and its structure by the amount and sequence of transitions between its elementary processes. A set of types is batched to a mix. Mixes of identical cost are considered as equivalent amounts of workload. These formalized descriptions of workloads allow investigators to compare the results of different studies quantitatively. Since workloads of different composition are assigned a unit of cost, these descriptions enable determination of cost effectiveness of different workloads on a machine. Subsequently performance parameters such as throughput rate, gain factor, internal and external delay factors are defined and used to demonstrate the effects of various workload attributes on the performance of a selected large scale computer system.
Yoon, Sang-Young; Ko, Jeonghan; Jung, Myung-Chul
2016-07-01
The aim of study is to suggest a job rotation schedule by developing a mathematical model in order to reduce cumulative workload from the successive use of the same body region. Workload assessment using rapid entire body assessment (REBA) was performed for the model in three automotive assembly lines of chassis, trim, and finishing to identify which body part exposed to relatively high workloads at workstations. The workloads were incorporated to the model to develop a job rotation schedule. The proposed schedules prevent the exposure to high workloads successively on the same body region and minimized between-worker variance in cumulative daily workload. Whereas some of workers were successively assigned to high workload workstation under no job rotation and serial job rotation. This model would help to reduce the potential for work-related musculoskeletal disorders (WMSDs) without additional cost for engineering work, although it may need more computational time and relative complex job rotation sequences. Copyright © 2016 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Structured analysis and modeling of complex systems
NASA Technical Reports Server (NTRS)
Strome, David R.; Dalrymple, Mathieu A.
1992-01-01
The Aircrew Evaluation Sustained Operations Performance (AESOP) facility at Brooks AFB, Texas, combines the realism of an operational environment with the control of a research laboratory. In recent studies we collected extensive data from the Airborne Warning and Control Systems (AWACS) Weapons Directors subjected to high and low workload Defensive Counter Air Scenarios. A critical and complex task in this environment involves committing a friendly fighter against a hostile fighter. Structured Analysis and Design techniques and computer modeling systems were applied to this task as tools for analyzing subject performance and workload. This technology is being transferred to the Man-Systems Division of NASA Johnson Space Center for application to complex mission related tasks, such as manipulating the Shuttle grappler arm.
Heavy vehicle driver workload assessment. Task 5, workload assessment protocol
DOT National Transportation Integrated Search
This report presents a description of a prescriptive workload assessment protocol for use in evaluating in-cab devices in heavy vehicles. The primary objective of this heavy vehicle driver workload assessment protocol is to identify the components an...
Timesharing performance as an indicator of pilot mental workload
NASA Technical Reports Server (NTRS)
Casper, Patricia A.; Kantowitz, Barry H.; Sorkin, Robert D.
1988-01-01
Attentional deficits (workloads) were evaluated in a timesharing task. The results from this and other experiments were incorporated into an expert system designed to provide workload metric selection advice to non-experts in the field interested in operator workload.
A user-oriented synthetic workload generator
NASA Technical Reports Server (NTRS)
Kao, Wei-Lun
1991-01-01
A user oriented synthetic workload generator that simulates users' file access behavior based on real workload characterization is described. The model for this workload generator is user oriented and job specific, represents file I/O operations at the system call level, allows general distributions for the usage measures, and assumes independence in the file I/O operation stream. The workload generator consists of three parts which handle specification of distributions, creation of an initial file system, and selection and execution of file I/O operations. Experiments on SUN NFS are shown to demonstrate the usage of the workload generator.
Crew workload-management strategies - A critical factor in system performance
NASA Technical Reports Server (NTRS)
Hart, Sandra G.
1989-01-01
This paper reviews the philosophy and goals of the NASA/USAF Strategic Behavior/Workload Management Program. The philosophical foundation of the program is based on the assumption that an improved understanding of pilot strategies will clarify the complex and inconsistent relationships observed among objective task demands and measures of system performance and pilot workload. The goals are to: (1) develop operationally relevant figures of merit for performance, (2) quantify the effects of strategic behaviors on system performance and pilot workload, (3) identify evaluation criteria for workload measures, and (4) develop methods of improving pilots' abilities to manage workload extremes.
Saito, Taiichi; Tamura, Manabu; Muragaki, Yoshihiro; Maruyama, Takashi; Kubota, Yuichi; Fukuchi, Satoko; Nitta, Masayuki; Chernov, Mikhail; Okamoto, Saori; Sugiyama, Kazuhiko; Kurisu, Kaoru; Sakai, Kuniyoshi L; Okada, Yoshikazu; Iseki, Hiroshi
2014-10-01
The objective in the present study was to evaluate the usefulness of cortico-cortical evoked potentials (CCEP) monitoring for the intraoperative assessment of speech function during resection of brain tumors. Intraoperative monitoring of CCEP was applied in 13 patients (mean age 34 ± 14 years) during the removal of neoplasms located within or close to language-related structures in the dominant cerebral hemisphere. For this purpose strip electrodes were positioned above the frontal language area (FLA) and temporal language area (TLA), which were identified with direct cortical stimulation and/or preliminary mapping with the use of implanted chronic subdural grid electrodes. The CCEP response was defined as the highest observed negative peak in either direction of stimulation. In 12 cases the tumor was resected during awake craniotomy. An intraoperative CCEP response was not obtained in one case because of technical problems. In the other patients it was identified from the FLA during stimulation of the TLA (7 cases) and from the TLA during stimulation of the FLA (5 cases), with a mean peak latency of 83 ± 15 msec. During tumor resection the CCEP response was unchanged in 5 cases, decreased in 4, and disappeared in 3. Postoperatively, all 7 patients with a decreased or absent CCEP response after lesion removal experienced deterioration in speech function. In contrast, in 5 cases with an unchanged intraoperative CCEP response, speaking abilities after surgery were preserved at the preoperative level, except in one patient who experienced not dysphasia, but dysarthria due to pyramidal tract injury. This difference was statistically significant (p < 0.01). The time required to recover speech function was also significantly associated with the type of intraoperative change in CCEP recordings (p < 0.01) and was, on average, 1.8 ± 1.0, 5.5 ± 1.0, and 11.0 ± 3.6 months, respectively, if the response was unchanged, was decreased, or had disappeared. Monitoring CCEP is feasible during the resection of brain tumors affecting language-related cerebral structures. In the intraoperative evaluation of speech function, it can be a helpful adjunct or can be used in its direct assessment with cortical and subcortical mapping during awake craniotomy. It can also be used to predict the prognosis of language disorders after surgery and decide on the optimal resection of a neoplasm.
3-Helium in Obscure H II Regions
NASA Astrophysics Data System (ADS)
Bania, T. M.; Rood, R. T.; Balser, D. S.
1999-05-01
The light isotope of helium, (3) He, can serve as a probe of cosmology, the evolution of low mass stars, and the chemical evolution of the Galaxy. Its abundance can be determined via measurements of the 3.46 cm hyperfine transition of (3) He(+) . Potentially observable sources of ionized gas include H ii regions and planetary nebulae. The selection of (3) He targets is counter-intuitive because the (3) He(+) hyperfine line strength is proportional to the source density, while one usually thinks of H ii regions in terms of radio continuum or recombination line strength both of which depend on the square of the density. The (3) He(+) line strength depends on the (3) He(+) abundance ratio and a number of other factors: $ TL(A}({) (3) He(+)) ~ frac {N((3) He(+)}{N() H(+)}) frac {({TC(A}}D)({1/2)) Te(1/4) (theta_obs (2) - theta_beam (2})({3/4}}{Delta {v}({)) (3) He(+)) [ln(5.717 x 10(-3}Te({3/2})]^{1/2)) theta_obs } where T_L^A and Delta v are the antenna temperature and FWHM of the ^3He^+ line, D is the nebular distance, T_C^A and theta_obs are the antenna temperature and observed FWHM angular size of the continuum emission, theta_beam is the telescope's FWHM beam, and Te is the nebular electron temperature. For H {sc ii} regions much larger than the telescope beam we can select targets using the criterion: TLA(^3He^+)\\sim\\sqrt{TCA D\\theta_obs}. This is the case since we can neglect the weak dependence on T_e and because we do not know either ^3He^{+}/H^+ or Delta v. Thus big, distant H ii regions could be potential ^3He^+ targets even if their continuum emission is weak. Armed with this knowledge we included H ii regions like S209 in our early observing list along with more famous sources like W43. Still we did not have the temerity to push this reasoning to the limit. We have now found, however, that this selection criterion is valid for even the wimpiest known H ii regions. Here we report on the detection of ^3He^+$ emission in 8 distant, low density H ii regions.
An evaluation of voice stress analysis techniques in a simulated AWACS environment
NASA Astrophysics Data System (ADS)
Jones, William A., Jr.
1990-08-01
The purpose was to determine if voice analysis algorithms are an effective measure of stress resulting from high workload. Fundamental frequency, frequency jitter, and amplitude shimmer algorithms were employed to measure the effects of stress in crewmember communications data in simulated AWACS mission scenarios. Two independent workload measures were used to identify levels of stress: a predictor model developed by the simulation author based upon scenario generated stimulus events; and the duration of communication for each weapons director, representative of the individual's response to the induced stress. Between eight and eleven speech samples were analyzed for each of the sixteen Air Force officers who participated in the study. Results identified fundamental frequency and frequency jitter as statistically significant vocal indicators of stress, while amplitude shimmer showed no signs of any significant relationship with workload or stress. Consistent with previous research, the frequency algorithm was identified as the most reliable measure. However, the results did not reveal a sensitive discrimination measure between levels of stress, but rather, did distinguish between the presence or absence of stress. The results illustrate a significant relationship between fundamental frequency and the effects of stress and also a significant inverse relationship with jitter, though less dramatic.