64 research outputs found
Assessment of mental workload air traffic controllers based on task load factors in air traffic control simulator
Background and aims: Air traffic control has known as a complex cognitive task, which requires controller to focus on task for long time. Mental workload plays an important role in the performance of controllers. The aim of this study was to assess the workload of air traffic controller on the basis of task load factors. Methods: The present descriptive-analytical study was conducted among fourteen air traffic controllers. First, air traffic control tasks were determined using hierarchical task analysis (HTA) technique and two low and high workload scenarios were designed based on the task load factors for controlling job. Next, the workloads of the controllers were assessed in these two scenarios by NASA-TLX inventory. Results: The results of HTA showed that air traffic control contains 49 main subtasks. The findings of the NASA-TLX showed that under high workload condition, mental demand with mean scores of 71/93 was the most overloaded task. Moreover, there were significant relationship between mental, physical, temporal demands, effort and frustration under high and low workload (p>0.05). Thus, it was not significant for performance variable under both low and high level conditions (p<0.05). Conclusion: The findings emphasize the importance of task load factors concerning air traffic controllers. Therefore, other evaluation methodologies is suggested with focused on the task load factors including Performance Assessment in all sectors of air traffic control center
Conventional and extended intramammary therapy of persistent subclinical mastitis using nafcillin-penicillin- dihydrostreptomycin in lactating dairy cattle
Summary The objective of the present study was to compare the efficacy of conventional and extended intramammary (IMM) therapy of persistent subclinical mastitis in lactating dairy cattle using nafcillinpenicillin-dihydrostreptomycin combination (NPD). Sixty-five dairy cows with 126 infected quarters were enrolled in the study. Infected cows were allocated randomly to 1 of 3 different treatment regimens: (1) conventional group: NPD administered IMM 3 times at 24-h intervals (20 infected cows, 43 intramammary infections [IMI]), (2) extended group: NPD administered IMM 6 times at 24-h intervals (23 cows, 43 IMI), and (3) untreated control group (22 cows, 40 IMI). The overall bacteriological cure (BC) rates for subclinical IMI were 86.04%, 100%, and 20% for the conventional, extended and the control groups, respectively; indicating a higher BC rate (P<0.0001) for the treated groups than the control group. Significant difference (P=0.029) concerning the BC rate was also observed between the extended and the conventional groups. Significant difference (P=0.0021) in somatic cell count (SCC) was detected between the extended and the control group. Fat percentage increased in the conventional (P=0.029) and in the extended (P<0.0001) groups, and protein percentage increased only in the extended group (P=0.0016). There was no significant difference in posttreatment milk production between the groups (P>0.05). Results of this study indicate that NPD therapy was effective in eliminating subclinical IMI in lactating dairy cows, and that extended therapy enhanced BC rate and reduced SCC
High-Affinity Naloxone Binding to Filamin A Prevents Mu Opioid Receptor–Gs Coupling Underlying Opioid Tolerance and Dependence
Ultra-low-dose opioid antagonists enhance opioid analgesia and reduce analgesic tolerance and dependence by preventing a G protein coupling switch (Gi/o to Gs) by the mu opioid receptor (MOR), although the binding site of such ultra-low-dose opioid antagonists was previously unknown. Here we show that with approximately 200-fold higher affinity than for the mu opioid receptor, naloxone binds a pentapeptide segment of the scaffolding protein filamin A, known to interact with the mu opioid receptor, to disrupt its chronic opioid-induced Gs coupling. Naloxone binding to filamin A is demonstrated by the absence of [3H]-and FITC-naloxone binding in the melanoma M2 cell line that does not contain filamin or MOR, contrasting with strong [3H]naloxone binding to its filamin A-transfected subclone A7 or to immunopurified filamin A. Naloxone binding to A7 cells was displaced by naltrexone but not by morphine, indicating a target distinct from opioid receptors and perhaps unique to naloxone and its analogs. The intracellular location of this binding site was confirmed by FITC-NLX binding in intact A7 cells. Overlapping peptide fragments from c-terminal filamin A revealed filamin A2561-2565 as the binding site, and an alanine scan of this pentapeptide revealed an essential mid-point lysine. Finally, in organotypic striatal slice cultures, peptide fragments containing filamin A2561-2565 abolished the prevention by 10 pM naloxone of both the chronic morphine-induced mu opioid receptor–Gs coupling and the downstream cAMP excitatory signal. These results establish filamin A as the target for ultra-low-dose opioid antagonists previously shown to enhance opioid analgesia and to prevent opioid tolerance and dependence
Primary antibody deficiency in a tertiary referral hospital: A 30-year experiment
Background: Primary antibody deficiency (PAD) is the most common group of primary immunodeficiency disorders (PID), with a broad spectrum of clinical features ranging from severe and recurrent infections to asymptomatic disease. Objectives: The current study was performed to evaluate and compare demographic and clinical data in the most common types of PAD. Materials and Methods: We performed a retrospective review of the medical records of all PAD patients with a confirmed diagnosis of common variable immunodeficiency (CVID), hyper IgM syndrome (HIgM), selective IgA deficiency (SIgAD), and X-linked agammaglobulinemia (XLA) who were diagnosed during the last 30 years at the Children�s Medical Center, Tehran, Iran. Results: A total number of 280 cases of PAD (125 CVID, 32 HIgM, 63 SIgAD, and 60 XLA) were enrolled in the study. The median (range) age at the onset of disease in CVID, HIgM, SIgAD, and XLA was 2 (0-46), 0.91 (0-9), 1 (0-26), and 1 (0-10) years, respectively. Gastrointestinal infections were more prevalent in CVID patients, as were central nervous system infections in XLA patients. Autoimmune complications were more prevalent in HIgM patients, malignancies in CVID patients, and allergies in SIgAD patients. The mortality rate for CVID, HIgM, and XLA was 27.2, 28.1, and 25, respectively. No deaths were reported in SIgAD patients. Conclusions: SIgAD patients had the best prognosis. While all PAD patients should be monitored for infectious complications, special attention should be paid to the finding of malignancy and autoimmune disorders in CVID and HIgM patients, respectively. © 2015 Esmon Publicidad
Primary immunodeficiency disorders in Iran: Update and new insights from the third report of the national registry
Background: Primary immunodeficiency disorders (PID) are a group of heterogeneous disorders mainly characterized by severe and recurrent infections and increased susceptibility to malignancies, lymphoproliferative and autoimmune conditions. National registries of PID disorders provide epidemiological data and increase the awareness of medical personnel as well as health care providers. Methods: This study presents the demographic data and clinical manifestations of Iranian PID patients who were diagnosed from March 2006 till the March of 2013 and were registered in Iranian PID Registry (IPIDR) after its second report of 2006. Results: A total number of 731 new PID patients (455 male and 276 female) from 14 medical centers were enrolled in the current study. Predominantly antibody deficiencies were the most common subcategory of PID (32.3 %) and were followed by combined immunodeficiencies (22.3 %), congenital defects of phagocyte number, function, or both (17.4 %), well-defined syndromes with immunodeficiency (17.2 %), autoinflammatory disorders (5.2 %), diseases of immune dysregulation (2.6 %), defects in innate immunity (1.6 %), and complement deficiencies (1.4 %). Severe combined immunodeficiency was the most common disorder (21.1 %). Other prevalent disorders were common variable immunodeficiency (14.9 %), hyper IgE syndrome (7.7 %), and selective IgA deficiency (7.5 %). Conclusions: Registration of Iranian PID patients increased the awareness of medical community of Iran and developed diagnostic and therapeutic techniques across more parts of the country. Further efforts must be taken by increasing the coverage of IPIDR via electronically registration and gradual referral system in order to provide better estimation of PID in Iran and reduce the number of undiagnosed cases. © 2014 Springer Science+Business Media
In vitro maturation of sheep oocytes in different concentrations of mare serum
The aim of the study was to determine the optimum concentration of the mare serum (MS) for sheep in vitro oocyte maturation. Sheep ovaries were collected from a local abattoir and transported within 1 h tothe laboratory in a warm saline solution (30 – 35oC), supplemented with 100 IU penicillin G and 100 g streptomycin sulfate/ml. Cumulus-oocyte complexes (COC’s) were obtained by slicing of follicles, washed in TCM-199 modification with NaHCO3 and supplemented with 50 g/ml gentamycin, and 0.25 mM sodium pyruvate without any serum supplementation. The COC’s were randomly divided into four groups. Group 1 (n = 105) COC’s were fresh control and cultured in TCM-199 medium without serum supplementation. Group 2 (n = 108) COC’s were washed five times and cultured in TCM-199 medium supplemented with 10% MS. Group 3 (n = 112) COC’s were washed five times and cultured in TCM-199medium supplemented with 15% MS. Group 4 (n = 114) COC’s were washed five times and cultured in TCM-199 medium supplemented with 20% MS. After 38 - 42 h of IVM, oocytes were denuded with the aidof 0.1% hyaluronidase and passing them through a fine pipette, fixed for 24 – 48 h in a mixture of acetic acid and alcohol (1:3) at room temperature, stained for 10 min with 1% (w/v) orcein in 45% acetic acid and examined for the evidence of different stages of maturation. Significantly higher (p < 0.05) maturation rates of oocytes (69 – 72%) were observed in all concentrations of mare serum compared tothose without serum supplementation. However, no significant difference was observed between the 10, 15 and 20% serum supplemented group
- …