213 research outputs found
Amplitude and Sign Adjustment for Peak-to-Average-Power Reduction
In this letter, we propose a method to reduce the peak-to-mean-envelope-power ratio (PMEPR) of multicarrier signals by modifying the constellation. For-ary phase-shift keying constellations, we minimize the maximum of the multicarrier signal over the sign and amplitude of each subcarrier. In order to find an efficient solution to the aforementioned nonconvex optimization problem, we present a suboptimal solution by first optimizing over the signs, and then optimizing over the amplitudes given the signs. We prove that the minimization of the maximum of a continuous multicarrier signal over the amplitude of each subcarrier can be written as a convex optimization problem with linear matrix inequality constraints. We also generalize the idea to other constellations such as 16-quadrature amplitude modulation. Simulation results show that by an average power increase of 0.21 dB, and not sending information over the sign of each subcarrier, PMEPR can be decreased by 5.1 dB for a system with 128 subcarriers
Peak to average power reduction using amplitude and sign adjustment
In this paper, we propose a method to reduce the peak to mean envelope power ratio (PMEPR) of multicarrier signals by modifying the constellation. For MPSK constellations,
we minimize the maximum of the multicarrier signal over the
sign and amplitude of each subcarrier. In order to find an efficient solution to the aforementioned non-convex optimization problem, we present a suboptimal solution by first optimizing over the signs using the result of [1], and then optimizing over the amplitudes given the signs. We prove that the minimization of the maximum of a multicarrier signal over the amplitude of each subcarrier can be written as a convex optimization problem with linear matrix inequality constraints. We also generalize the idea to other
constellations such as 16QAM. Simulation results show that by an average power increase of 0.21 db and not sending information over the sign of each subcarrier, PMEPR can be decreased by 5.1 db for a system with 128 subcarriers
Écriture-dévoilement ou la méthodologie historique au service de la littérature : Mes soixante ans de Constance de Salm
Cuando una obra literaria no pretende mezclar realidad y ficción, sino escribir lo real
con las operaciones cognitivas que esto implica, la literatura se convierte en una herramienta
para explicar y comprender el mundo. Mes Soixante ans de Constance de Salm es un texto
literario que, a pesar del discurso que ejemplifica, se asemeja a una obra histórica. Tras analizar la naturaleza híbrida de la obra con la ayuda de diferentes elementos del método histórico
–como la posición del “yo” del investigador, la movilización de referencias y evidencias, la
estructuración cronológica del documento– y del comparatismo, nos proponemos demostrar
la inteligibilidad científica del poema.La littérature devient un outil d’explication-compréhension du monde lorsqu’une œuvre littéraire ne vise pas à mélanger le factuel et la fiction mais à écrire le Réel avec les opérations cognitives que cela suppose. Mes soixante ansde Constance de Salm est un texte constitutivement littéraire qui pourtant, par le discours qu’il exemplifie, s’apparente à un ouvrage historique. Après avoir analysé le caractère hybride de l’œuvre, à l’aide de divers élé-ments de la méthodologie historique comme la position du « je » de chercheur, la mobilisa-tion des sources et des preuves, la structuration chronologique du document ainsi que le comparatisme, nous allons démontrer l’intelligibilité scientifique du poème.When a work of literature doesn’t aim to mix fact with fiction but aims to write the reality with the cognitive operations that it’s assumed, the literature becomes a tool of expla-nation and comprehension of the world. Mes soixante ansis a literary text which can present itself as a historical work by using the type of discourse that it illustrates. After analyzing the hybrid character of the work, the position of the “I” of the method, the movement of the sources and the evidence, the chronological structuring of the document as well as compara-tism, are the various elements of the historical methodology; with the help of which the his-torical intelligibility of the poem is then demonstrated
Cytotoxicity of Triple Antibiotic Paste and Calcium Hydroxide against Cultured Human Dental Pulp Fibroblasts
Objective: In necrotic immature teeth, intra canal medicaments such as triple antibiotic paste (TAP) and calcium hydroxide (CH) are used for root canal disinfection and regeneration treatment. However, the effect of these medicaments on dental pulp fibroblasts has yet to be known. This study aimed to assess the cytotoxicity of CH and TAP against cultured human dental pulp fibroblasts (HDPFs) obtained from third molars.Methods: In this in vitro study, fibroblasts were obtained from the dental pulp of two third molars. Fibroblasts were exposed to 0.1, 1 and 10 mg/mL concentrations of TAP and CH. Six samples were prepared of each medicament and fibroblast viability was evaluated after 72 hours. Data were analyzed using one-way and two-way ANOVA (p<0.001). The percentage of cell viability was calculated and the cytotoxicity of the medicament was categorized as severe (30%), moderate (30- 60%), mild (60-90%) and non-toxic (>90%).Results: In TAP samples, only the 10 mg/mL concentration had a significant difference with the control group in terms of the percentage of cell viability and showed moderate cytotoxicity. In CH samples, the 1 and 10 mg/mL concentrations showed significant differences with the control group and were severely cytotoxic.Conclusion: Reduction in cell viability of fibroblasts by increase in concentration was significantly greater in CH compared to TAP group. Thus, in regeneration treatments, these medicaments must be used in concentrations with adequate therapeutic and insignificant adverse effects on fibroblasts
Gender Differences in Treatment Seeking Gamblers with a Comorbid Eating Disorder
Abstract: Recent literature suggests that gambling and eating disorders may co-occur more frequently than once thought. However, no studies have directly examined whether gender differences exist in comorbid gambling and eating disorders. The present study investigated gender differences in current gambling behaviors, gambling severity, gambling-related cognitive distortions, and psychiatric comorbidities in dual-diagnosed participants. The sample consisted of 349 treatment-seeking gamblers at a university hospital in São Paulo, Brazil. Gambling disorder and other psychiatric comorbidities were assessed via comprehensive clinical interviews. Of the total sample, 43 participants met criteria for both a gambling and eating disorder, and subsequently completed a series of self-report measures to evaluate gambling behaviours, gambling severity, and cognitive distortions related to gambling. No gender differences were found in any gambling variables. In contrast, several gender differences were found in current psychiatric co-morbidities. Although women were more likely to have an eating disorder diagnosis (n = 28; 8.0%) than men (n = 15; 4.3%), men were more likely to report comorbid depression, alcohol use disorder, and compulsive sexual behaviors. The gender differences observed provide further evidence for the need to consider gender-specific patterns of presentation in treatment for eating and gambling disorders.
Implications: The greater psychopathology observed in male versus female gamblers with an eating disorder may call for clinicians to carefully consider and screen for other associated psychological problems in this population and to incorporate brief eating disorder screens such as the ‘SCOFF clinical prediction guide’ within gambling intervention programs
In vivo analgesic and anti-inflammatory effects of the essential oil from Tanacetum balsamita L.
Tanacetum balsamita locally called Shahesparam is an aromatic plant that grows widely in Azerbaijan Province, Iran. Due to the widespread use of T. balsamita as a pain killer and relief of inflammatory based disorders in Iranian folk medicine and considering the high content of essential oil in T. balsamita aerial parts, we were prompted to investigate the anti-nociceptive and anti-inflammatory properties of T. balsamita essential oil (TBEO) for the first time. The carrageenan-induced Paw Edema was used for inflammation evaluation in rat, and hot-plate method was used for pain assessment in mice. Different doses of TBEO were administered. Morphine and Mefenamic acid were used as the standard drugs in antinociceptive and anti-inflammatory evaluation tests, respectively. TBEO (100 mg/kg) showed significantly anti-nociceptive activity in hot-plate test. The anti-inflammatory activity of TBEO was found to be more than mefenamic acid. The studied oil was analyzed by GC and GC–MS. The major component of the oil was characterized as carvone (39.8%) which might be responsible for the observed activities. The results suggested that TBEO possessed biologically active constituents that had significant analgesic and anti-inflammatory effects which support the ethno-medicinal claims of the plant application in the management of pain and inflammation
The Effects of Simulation Training on Nursing Students’ Knowledge and Skill in Cardiopulmonary Resuscitation
Background & Objective: Providing a more realistic training environment can help learners to
better understand what they were taught. Nursing students can be prepared for real critical
scenarios such as cardiopulmonary resuscitation (CPR) by using simulation in training. This
study was aimed to evaluate the effect of simulation training on nursing students’ knowledge and
skill in CPR.
Methods: This was a quasi-experimental study with pre- and post-test on 30 participants. Data
was collected using a questionnaire before and after the training. The results were analyzed by
ANOVA and paired t-test using SPSS.
Results: In the pre-test, knowledge score was 10.50 ± 0.16 while in the post-test it was 17.60 ±
0.18. Also skill score in the pre-test and post-test was 11.50 ± 4.74 and 18.47 ± 2.17,
respectively. Comparing the means showed a significant difference between the results of preand
post-test (P = 0.030).
Conclusion: According to the results of this study, simulation method improved nursing students
knowledge and skills and should be considered in education planning by authorities.
Key Words: Simulation, Cardiopulmonary resuscitation (CPR), Nursing students, Awareness,
Skil
Application of Transtheoretical Model to Exercise in Office Staff
Abstract:Background: Transtheoretical model is identified as a comprehensive model for behavior exercise. The aim of this study was to check the situation of stage of change in exercise behavior of office personnel of Yazd city using transtheoretical model.Methods: In a cross-sectional study, 220 office personnel selected from administrative offices of Yazd through two-stage cluster-sampling method. The instrument for data collection was a questionnaire that included demographic variables and constructs of transtheoretical model. The reliability and validity of the instruments were examined and approved by experts. The data was analyzed using SPSS soft ware.Results: 152 males (69.1%) and 68 females (30.9%) with an average age of 34±8.68 years were selected. Sixty percent of the subjects were in precontemplation and contemplation stages and only 7.3% were in action stages. Significant differences were found between TTM constructs and stages of change (P=0.000). The results also showed significant differences between components of decisional balance and behavioral process and cognitive process with the stages of change. We found that behavioral process of change and self efficacy were the most important variables for improving levels of exercise.Conclusion: Most of the participants were in the precontemplation and contemplation stages and most problems were related to behavioral process and self efficacy. Therefore, strategies and programs are needed to be taken into account to improve exercise among the staff
Aprendices iraníes de inglés y la realización de la condolencia: Un estudio pragmático interlenguaje
This study was an attempt to examine Iranian EFL learners’ realization of the condolence speech act in English and to compare their realization with English native speakers’ (NSs) realization patterns. The study was further interested in investigating whether Iranian EFL learners’ realization of the condolence speech act is associated with their level of L2 proficiency. To this end, a Discourse Completion Test (DCT) was administered to 82 undergraduate Iranian EFL students in English. The participants were divided into three levels of language proficiency (elementary level, intermediate level, and advanced level) based on their scores on the Oxford Quick Placement Test (OQPT). For baseline comparisons, the EFL learners also received the translated version of the same DCT in Persian, and the English DCT was administered to 20 NSs of American English. The data were analyzed based on Elwood’s (2004) coding scheme. The results revealed that Iranian EFL learners had access to the same condolence strategies as English NSs, yet they differed in the semantic formulas, content, or forms they adopted to formulize their condolence expressions. In addition, level of L2 proficiency was found to be associated with Iranian EFL learners’ realization of the condolence speech act.Este estudio fue un intento de examinar la realización de los estudiantes iraníes del acto de discurso de condolencia en inglés y comparar su realización con los patrones de realización de los hablantes nativos de inglés. El estudio también se interesó en investigar si la realización por parte de los estudiantes iraníes de inglés de la ley del discurso de condolencia está asociada con su nivel de competencia en la segunda lengua. Con este fin, se aplicó una Prueba de Finalización del Discurso a 82 estudiantes universitarios iraníes en inglés. Los participantes fueron divididos en tres niveles de dominio del idioma (niveles elemental, intermedio y avanzado) basados en sus calificaciones en el Oxford Quick Placement Test (OQPT). Para las comparaciones de línea de base, los estudiantes de EFL también recibieron la versión traducida del mismo DCT en persa, y el DCT inglés se administró a 20 hablantes nativos de inglés americano. Los datos fueron analizados con base en el esquema de codificación de Elwood (2004). Los resultados revelaron que los estudiantes iraníes de inglés tenían acceso a las mismas estrategias de condolencia que los nativos ingleses, aunque diferían en las fórmulas semánticas, contenido o formas que adoptaron para formular sus expresiones de condolencia. Además, se encontró que el nivel de competencia en segunda lengua estaba asociado con la realización por parte de los estudiantes iraníes de la ley de discurso de condolencia
Indomethacin-Enhanced Anticancer Effect of Arsenic Trioxide in A549 Cell Line: Involvement of Apoptosis and Phospho-ERK and p38 MAPK Pathways
Background. Focusing on novel drug combinations that target different pathways especially apoptosis and MAPK could be a rationaleforcombinationtherapyinsuccessfultreatmentoflungcancer.Concurrentuseofcyclooxygenase(COX)inhibitorswith arsenictrioxide(ATO)mightbeapossibletreatmentoption.Methods.CytotoxicityofATO,dexamethasone(Dex),celecoxib(Cel), andIndomethacin(Indo)individuallyorincombinationwasdeterminedat24,48,and72hrsinA549lungcancercells.TheCOX-2 gene and protein expression, MAPK pathway proteins, and caspase-3 activity were studied for the most cytotoxic combinations. Results. The IC 50s of ATO and Indo were 68.
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