32 research outputs found
Evaluation of the Levels of Evidence in Three Clinical Chapters in Five Editions of the Textbook Pathways of the Pulp
Introduction: The levels of evidence (LOE) of dental education texts is critical from the educational point of view. The present study aimed to evaluate the levels of evidence of references used in three clinical chapters in the textbook Pathways of the Pulp. Material & Method: The references of three clinical chapters in the text book Pathways of the Pulp were assessed in five of its editions. The levels of evidence were ranked according to study type and the Oxford scale from 0 to 5. The chi-square test was used to compare the level of evidence between different editions of the "Retreatment," "Trauma," and "Surgery" chapters. Results: A total of 3656 references were reviewed and analyzed from the "Trauma" (928 references), "Re-treatment" (1906 references), and "Surgery" (822 references) chapters in the 1998, 2002, 2006, 2011, and 2016 editions. The percentage of the LOE 0 (no evidence) was high (>60%) in all three chapters in all editions (P<0.001). The levels of evidence had the same distribution in all editions (P=0.871). The LOE of the "Re-treatment" (P=0.044) and "Surgery" (P<0.001) chapters changed in some editions. Conclusion: The majority of references in the three clinical chapters of the book are low-level evidence. Encouragement policies for researchers to conduct studies with high LOE are necessary
Source identification and ecological risk assessment of polycyclic aromatic hydrocarbons in surface sediments (Case study: Pars special economic energy zone)
Background and purpose: Polycyclic aromatic hydrocarbons (PAH) compounds are amongst the most hazardous environmental pollutants due to some features such as chemical stability, low degradation, bioaccumulation, and high toxicity for living organisms. Their resources are found in Persian Gulf beaches, so, this study aimed at investigating the concentration, source identification, and ecological risk of PAH compounds in coastal sediments in Pars Special Economic Energy Zone (PSEEZ), Iran. Materials and methods: In order to assess the concentration of PAHs, 16 stations along the coast were selected and in each station two samples were collected. After preparation and extraction of samples using Soxhlet, the concentrations of these compounds were determined by HPLC. The toxicity evaluation indicators and diagnostic ratios were used to assess the ecological risk and determining their origin. Results: Mean concentration of PAHs in sediment was 292.72±54.44 ng/g dry weight. The mean effects range-median quotient of the PAHs (M-ERM-Q, M-PEL-Q), toxic equivalence quotient (TEQ), and mutagenic equivalence quotient (MEQ) showed that current values were less than the permissible limit. Comparison of PAHs concentration with sediment quality standards (NOAA, SQGs, and EPA) showed that the values for all compounds were lower than the standard limits (PEC, TEC, PEL, TEL, ERM). However, among these compounds, the average concentration of Acl was higher than the ERL standard and the concentrations of Acl, Ace, and Phe were higher than the EPA toxicity threshold. Conclusion: In this study, moderate PHAs pollution was seen in the region. Both petrogenic and fuel sources were found to be involved in introduction of these compounds into coastal sediments depending on the location of the station and its sources of contamination. Also, in terms of ecological risk, these compounds have low risks for living organisms. © 2018, Mazandaran University of Medical Sciences. All rights reserved
Determination and Ecological Risk Assessment of Heavy Metals (Cd, Pb, Cu, Zn) in Surface Sediments of Coastal Regions of Bushehr Province
Background: Persian Gulf is one of the most important ecosystems in the world that in recent
decades has been exposed to various environmental pollutants such as heavy metals from human and
natural activities. Therefore, the aim of this study investigates the concentration of heavy metals
(cadmium, lead, copper and zinc) and ecological risk assessment of them in coastal sediments in of
Bushehr province in Persian Gulf.
Methods: In order to assess the concentration of metals, 54 stations along the coastal zones were
selected and in each station three samples of sediment and plant were taken. After preparation and
digestion of the samples, the concentrations of these metals were determined by using polarography.
Results: The average of total concentration of detected metals Zn, Cu, Pb and Cd in sediment 52.40
± 2. 62, 34.99±2.76, 11.53 ±2.01 and 2.41± 0.89 μg/g, respectively. Also, the results of comparison
of heavy metals concentration in coastal areas in Bushehr Province (Jam, Deir, Bushehr, Dashti,
Genaveh and Deilam) with ANOVA test showed there was a significant difference between the
concentrations of sediments in different coastal areas. The results showed that the Pollution Load
Index (PLI) and ecological risk represents less to moderately pollution in the region. Also, the
environmental risk of metals in the region was evaluated as (Cd>Cu> Pb> Zn).
Conclusion: According to the results, the pollution and ecological risk of metals in the region for Zn,
Cu and Pb is low but for Cd is moderateevaluated
The Effectiveness of Different Eyewitness Interview Tools in Memory Consolidation for Long-term Access
This study examines the effectiveness of different interviewing tools in consolidating eyewitness memory. This applied research used the post-test with control group design. The population includes all undergraduate students of the Faculty of Psychology and Educational Science of the University of Tehran, studying in the academic year 2019-20. Eighty participants (21 males and 59 females) were selected using cluster sampling and divided into four groups of equal size. First, participants watched a video recording showing a bank robbery. In the second session, they were interviewed using an eyewitness interview tool (no interview session for the control group). In the last session, all participants were examined using a free recall task. Data were analyzed using MANOVA in SPSS-23 software. The results indicated no significant differences between the CI and the self-administered interview groups (SAI) in either the interview session or the delayed recall task. Participants in the structured interview group recalled significantly fewer details in the first interview session than did the CI and SAI groups. However, this significant difference was only found between the CI and SI groups in the delayed recall session. Thus, the results suggest that early recall can help consolidate witnesses' memory and help them recall more information in later recall attempts
Suicide attempts, suicide and their association with socio-demographic variables in Iran: a retrospective, registry-based, cohort study (2016-2021)
INTRODUCTION: Suicide is recognized as one of the most significant concerns in healthcare and a serious psychological health issue in many countries throughout the world. Suicide attempts occur in all social sectors and demographics. It is important to know what are the causes for people to try to commit suicide for an effective prevention and control. The aim of this review was to find out the levels and predictors of suicide attempts.
MATERIAL AND METHODS: A cross-sectional descriptive-analytical research looked for suicide attempt reported cases at Dr. Moaven Hospital in Sahneh, Iran, during the 2016–2021 period. Data was collected via checklists completed by supervisors during referrals and subsequently analyzed using the SPSS Statistics software tool (version 24). Descriptive statistics and the Chi-square test were used. A significance threshold of 0.05 was used.
RESULTS: A total of 1,059 cases of suicide attempts were found. The highest prevalence rate was reported in the group ages 16–25. Males had higher rates of cases (57.4%), which were twice more prevalent in cities and more common in lower-socioeconomic-status families Furthermore, the most common method used (79.5%) was medication intake. There was also a significant association between marital status, job, and suicide-attempt rates (p < 0.05).
CONCLUSIONS: Suicide attempts are among the most important issues in terms of psychosocial healthcare in all countries and communities, and their prevalence rates may be determined by a variety of factors, such as mental health status, family and living conditions, financial problems and unemployment rate. Preventive control of these factors can contribute to reducing the prevalence of these acts
To which world regions does the valence–dominance model of social perception apply?
Over the past 10 years, Oosterhof and Todorov’s valence–dominance model has emerged as the most prominent account of how people evaluate faces on social dimensions. In this model, two dimensions (valence and dominance) underpin social judgements of faces. Because this model has primarily been developed and tested in Western regions, it is unclear whether these findings apply to other regions. We addressed this question by replicating Oosterhof and Todorov’s methodology across 11 world regions, 41 countries and 11,570 participants. When we used Oosterhof and Todorov’s original analysis strategy, the valence–dominance model generalized across regions. When we used an alternative methodology to allow for correlated dimensions, we observed much less generalization. Collectively, these results suggest that, while the valence–dominance model generalizes very well across regions when dimensions are forced to be orthogonal, regional differences are revealed when we use different extraction methods and correlate and rotate the dimension reduction solution
A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.
The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world
Control of Horizontal Axis Wind Turbine with Synchronous Generator to Capture Maximum Energy of Wind
Three types of generator named wound rotor synchronous generator (WRSG), permanent magnet synchronous generator (PMSG) and doubly fed induction generator (DFIG) are usually used in variable speed horizontal axis wind turbines. Synchronous generator with controlled excitation voltage is a proper solution for power production in rotational speed lower than the nominal. In this paper, excitation voltage controller is designed to capture maximum energy of wind and pitch angle controller is designed to regulate the rotational speed of rotor when wind speed is over the rated value. Simulation results are verified by means of HIL (Hardware In the Loop) test setup. In this case, the function of controllers are examined in a turbulent wind condition on a simulator and the performance is analyzed. Finally, it is concluded that MPPT (Maximum Power Point Tracking) algorithm can be performed by controlling the excitation voltage of a synchronous generator in a below rated condition
Finite Deformation of Scleral Tissue under Electrical Stimulation: An Arbitrary Lagrangian-Eulerian Finite Element Method
The sclera is considered as the principal load-bearing tissue within the eye. The sclera is negatively charged; thus, it exhibits mechanical response to electrical stimulation. We recently demonstrated the electroactive behavior of sclera by performing experimental measurements that captured the deformation of the tip of scleral strips subjected to electric voltage. We also numerically analyzed the electromechanical response of the tissue using a chemo-electro-mechanical model. In the pre-sent study, we extended our previous work by experimentally characterizing the deformation profile of scleral strips along their length under electrical stimulation. In addition, we improved our previous mathematical model such that it could numerically capture the large deformation of samples. For this purpose, we considered the transient variability of the fixed charge density and the coupling between mechanical and chemo-electrical phenomena. These improvements in-creased the accuracy of the computational model, resulting in a better numerical representation of experimentally measured bending angles
Effects of a digital guided peer feedback system on student learning and satisfaction
This study investigates the effects of a digital guided peer feedback on students’ learning and satisfaction. Participants were 203 students who were randomly assigned to groups of three. students were asked to explore various perspectives, and the 'pros and cons' on the topic of 'Genetically Modified Organisms (GMOs)'. The findings show that the digital module fosters students’ learning and satisfaction.</p