2,314 research outputs found
Psychogenic non-epileptic seizures in Iran
AbstractPurposeWe investigated the demographic and clinical characteristics of psychogenic non-epileptic seizures (PNES) in patients in Iran.MethodsIn this prospective study, all patients with a clinical diagnosis of PNES (based on ictal recordings) were recruited at the outpatient epilepsy clinic at Shiraz University of Medical Sciences, from 2008 through 2013. The epileptologist interviewed all the patients. We investigated the demographic and clinical characteristics of PNES.ResultsTwo hundred and forty-nine patients were diagnosed as having PNES. Two hundred and eleven patients had video-EEG recordings available and included in the study. One hundred and forty-one (66.8%) were female and 70 (33.2%) were male. There were no significant differences between our patients and previous reports regarding the clinical and semiological characteristics of PNES.ConclusionPsychogenic non-epileptic seizures are relatively common at epilepsy clinics. It appears that an Islamic lifestyle (in Iran) has little influence on the clinical characteristics and manifestations of PNES, as we observed similar results as in most previous studies from other cultures
Opportunities for optics in integrated circuits applications
Optics potentially addresses two key problems in electronic chips and systems: interconnects and timing. Short optical pulses (e.g., picoseconds or shorter) offer particularly precise timing. Results are shown for optical and electrical four-phase clocking, with <1 ps rms jitter for the optical case
Export Growth and Factor Market Competition: Theory and Evidence
Empirical evidence suggests that sectoral export growth decreases exporters\' survival probability, whereas non{exporters are unaffected. Models with firm heterogeneity in total factor productivity predict the opposite. To solve this puzzle, we develop a two-factor framework where firms differ in factor shares. In this model, export growth increases competition for the factor used intensively by exporters, eliminating some of them, while non-exporters benefit. Our empirical analysis shows that the forces highlighted in the model drive the firm selection experienced by the Chilean manufacturing sector, suggesting that heterogeneity in factor shares is crucial to understand how firms react to trade liberalization.Firm Dynamics, Two-Factor Trade Model, Firm Heterogeneity in Factor Shares, Chile, Manufacturing Industry
Robust detection, isolation and accommodation for sensor failures
The objective is to extend the recent advances in robust control system design of multivariable systems to sensor failure detection, isolation, and accommodation (DIA), and estimator design. This effort provides analysis tools to quantify the trade-off between performance robustness and DIA sensitivity, which are to be used to achieve higher levels of performance robustness for given levels of DIA sensitivity. An innovations-based DIA scheme is used. Estimators, which depend upon a model of the process and process inputs and outputs, are used to generate these innovations. Thresholds used to determine failure detection are computed based on bounds on modeling errors, noise properties, and the class of failures. The applicability of the newly developed tools are demonstrated on a multivariable aircraft turbojet engine example. A new concept call the threshold selector was developed. It represents a significant and innovative tool for the analysis and synthesis of DiA algorithms. The estimators were made robust by introduction of an internal model and by frequency shaping. The internal mode provides asymptotically unbiased filter estimates.The incorporation of frequency shaping of the Linear Quadratic Gaussian cost functional modifies the estimator design to make it suitable for sensor failure DIA. The results are compared with previous studies which used thresholds that were selcted empirically. Comparison of these two techniques on a nonlinear dynamic engine simulation shows improved performance of the new method compared to previous technique
Confinement interaction in nonlinear generalizations of the Wick-Cutkosky model
We consider nonlinear-mediating-field generalizations of the Wick-Cutkosky
model. Using an iterative approach and eliminating the mediating field by means
of the covariant Green function we arrive at a Lagrangian density containing
many-point time-nonlocal interaction terms. In low-order approximations of
theory we obtain the usual two-current interaction as well as
a three-current interaction of a confining type. The same result is obtained
without approximation for a version of the dipole model. The transition to the
Hamiltonian formalism and subsequent canonical quantization is performed with
time non-locality taken into account approximately.
A relativistic three-particle wave equation is derived variationally by using
a three-particle Fock space trial state. The non-relativistic limit of this
equation is obtained and its properties are analyzed and discussed.Comment: 15 pages, 1 figure, LaTe
Computation of Zeros of Linear Multivariable Systems
Several algorithms have been proposed in the literature for the computation of the zeros of a linear system described by a state-space model {A, B, C, D}. In this paper we discuss the numerical properties of a new algorithm and compare it with some earlier techniques of computing zeros. The method is a modified version of Silverman's structure algorithm and is shown to be backward stable in a rigorous sense. The approach is shown to handle both nonsquare and/or degenerate systems. Several numerical examples are also provided
Safety and efficacy of PDpoetin for management of anemia in patients with end stage renal disease on maintenance hemodialysis: Results from a phase IV clinical trial
Recombinant human erythropoietin (rHuEPO) is available for correcting anemia. PDpoetin, a new brand of rHuEPO, has been certified by Food and Drug Department of Ministry of Health and Medical Education of Iran for clinical use in patients with chronic kidney disease. We conducted this post-marketing survey to further evaluate the safety and efficacy of PDpoetin for management of anemia in patients on maintenance hemodialysis. Patients from 4 centers in Iran were enrolled for this multicenter, open-label, uncontrolled phase IV clinical trial. Changes in blood chemistry, hemoglobin and hematocrit levels, renal function, and other characteristics of the patients were recorded for 4 months; 501 of the patients recruited, completed this study. Mean age of the patients was 50.9 (±16.2) years. 48.7 of patients were female. Mean of the hemoglobin value in all of the 4 centers was 9.29 (±1.43) g/dL at beginning of the study and reached 10.96 (±2.23) g/dL after 4 months and showed significant increase overall (P<0.001). PDpoetin dose was stable at 50-100 U/kg thrice weekly. Hemorheologic disturbancesand changes in blood electrolytes was not observed. No case of immunological reactions to PDpoetin was observed. Our study, therefore, showed that PDpoetin has significantly raised the level of hemoglobin in the hemodialysis patients (about 1.7±0.6 g/dL). Anemia were successfully corrected in 49 of patients under study. Use of this biosimilar was shown to be safe and effective for the maintenance of hemoglobin in patients on maintenance hemodialysis. © A.N. Javidan et al., 2014
Reduced cost photonic instantaneous frequency measurement system
A wideband photonic instantaneous frequency measurement system is proposed and practically demonstrated. This system employs only a low-frequency inexpensive photodetector and thus the system cost is reduced
Social Accountability in Nursing Education: A Necessary Yet Neglected Issue
Background: Evidence-Based Practice (EBP) is one of the nursing professional roles that can lead them to provide the best and more effective care. However, no studies are available on nursing students’ competencies in EBP.
Objectives: This study aimed to investigate the nursing students’ knowledge, attitude and intention to implement EBP and its related factors in two nursing and midwifery faculties in Tehran, Iran.
Materials and Methods: In this cross-sectional study, 170 undergraduate nursing students were selected from two faculties of nursing and midwifery in Tehran, Iran. A census sampling method was applied and they were all before graduation in 2013. The Rubin and Parrish questionnaire was used to assess the students’ knowledge, attitude and intention to implement EBP as well as factors affecting the implementation of EBP. Students completed the instrument through self-report. Descriptive statistics, Independent sample t-test and Pearson correlation coefficient were used to analyze the data.
Results: The students mean scores of knowledge, attitude and intention to implement EBP was 31.08 ± 5.77, 50.40 ± 9.58, 36.01 ± 4.64, respectively. The students’ age was inversely correlated with their scores of knowledge, attitude and intention to use EBP (P < 0.05). However, the students’ GPA was in direct association with their knowledge, attitude and intention to implement EBP (P < 0.05). No significant differences were observed between the males and females mean scores in the three subscales. However, significant differences were found between the students mean scores in the two subscales of knowledge and attitudes toward EBP in terms of familiarity with statistics and research methods (P < 0.05). Neither familiarity with research methods nor familiarity with EBP could significantly affect the students’ intention to implement EBP.
Conclusions: The present study showed that nursing students have not a high mean score in the three subscales of knowledge, attitude and intention to implement EBP. It is essential for faculties and nurse managers not only to focus on education of EBP, but also to support nurses and nursing students to implement it in the process patient care
- …