dr. massoud sharifi

The purpose of the present study was to determine the relationship between circadian cycles and working memory of students.

The research was done using the correlation method. The statistical population consisted of the female students of the 11th grade in the central part of the Khodabandeh county,  from whom, 40 students were selected from two classes by random cluster sampling . They were tested for two weeks in two turns in the morning (at 8, 9.30, 11) and in the afternoon (at 13, 14.30, 16.15). The Horn and Stoberg (1976) questionnaire was used to assess the chronotype, and tests of equivalent forms of verbal memory assessment was used to measure the working memory. The mixed analysis of variance was used to analyze the data.

there was a significant difference between the efficiency of students' working memory at different hours of the day (f =2/82, p = 0/017) as well as the different days of the week (f =16/8, p < 0/0005). Differences in the efficiency of working memory were not significant among the chronotypes of morning, afternoon, and evening (f =0/301, p = 0/742). The efficiency of students' working memory was different according to the cronotype in different hours of the day (f =3/06, p = 0/001).

It is essential to pay attention to the circadian and weekly cycles in student education.

Human cognitive activities are affected by the time of doing homework, biologic rhythms and interaction among them.

this research accomplished to specify the fluctuation patterns of daily and weekly cycles of the students attention. The research method was correlation. The statistical population of this study were 45 female students in 11th grade from a high school in humanities branch from khodabandeh city in 2017- 2018 academic year, that have been selected through randomized cluster sampling method at two works in a rotational shiftwork at two times on mornings (8, 9/30, and 11 a. m) and afternoons( 13, 14/30 and 16/15 p. m). Horn and Ostberg questionnaire was used for evaluation of the chronotype of students and for the attention assessment the parallel forms of the d2 test administered. The mixed analysis of variance was used to analyze data.

there was a significant difference between efficiency of students' attention at different times of day and also difference in efficiency of students' attention in the morning, midday and evening chronotypes. Efficiency of students' attention was different in chronotypes at different hours of the day.

regarding the differences of efficiency of students' attention in circadian and weekly rhythms and also individual differences, it is necessary to consider them in teaching and learning process in educational environments.

The purpose of this study was to determine the effect of training of self-regulation strategies on students' mathematical and memory performance.
The research method was semi-experimental with the design of non-equivalent control groups. The statistical population of this study was all 167 female students of the 11th grade of human science major in high school of Khodabandeh in the academic year of 1396-1397, of which 40 students were random cluster selected as a sample and were divided into two groups: experimental and witness. The evaluation equivalent form tests of verbal and mathematical memory were used to evaluate the mathematical and memory performance. The experimental group was trained for 13 sessions by self-regulatory strategies, but the witness group did not receive any training on self-regulation strategies. Both groups respond to the examinations immediately before training, immediately after training and follow up stage of 4 months. The mixed variance was used to analyze the data.
The results showed that there was a significant difference between the experimental and witness groups in the post-test and follow-up stages in terms of math and memory tests. The experimental group had maintained its superiority in math and memory performance after 4 months.
Self-regulation strategies have learning and teaching capabilities and their effects are sustainable over time.

The purpose of this study was to determine the variations of the daily and weekly cycles of students' mathematical logic. The research was done in correlation method. The statistical population of the research was 11th grade of female students in human science in Khodabandeh city in 1396-1397. They were selected by random cluster sampling of 36 people in two classes. The test was performed for two weeks in two rounds of morning (8, 9.30, 11) and afternoon (13, 14.30, 16.15). The Horn and ostburg questionnaire (1976) was used to measure the chronotype, and the parallel forms tests of researched mathematical logic were used to measure the mathematical logic. The mixed analysis of variance was used to analyze the data. The results showed that there is a significant difference between the efficiency of students' mathematical logic at different hours of the day(f=4/215, p= ./0001), but the efficiency of mathematical logic was not significant in different days of the week. The efficiency difference of mathematical logic among the morning, afternoon, and evening was significant(f= 2/71, p= ./0004). The efficiency of students' mathematical logic differed significantly in terms of chronotype at different hours of the day(f= 3/028, p< ./0005). Regarding the differences in the efficiency of students' mathematical logic in terms of day and night rhythms as well as the individual differences in terms of chronotype, it is necessary that these results to be considered in the teaching and learning process in educational settings.

Chronopsychology researches claim that cognitive processes performance during learning in the educational environment in times of the day and days of the week fluctuate, and working memory is essential among these cognitive processes. The research aimed to study the rhythm of daily and weekly working memory performance of preschoolers based on their chronotype (morningness and eveningness) orientation. The research method is causal-comparative. The participants are 100 preschool children in Tehran that were selected based on purposive sampling. Their working memory was tested at different time intervals of (8, 11, 13, and 15) and weekly (Saturday, Sunday, Monday, Tuesday and Wednesday). Saturday also considered as the first day of the week. Data collection instrument were children morningness-eveningness preference (CMEP) in the form of questionnaire and working memory test. Data analysis based on a mixed analysis of variance. The results showed that preschoolers working memory performance during different days of the week and time of day was different (P < 0.01). There was a significant difference between children in different groups regarding memory at different hours of the day, but on different days of the week, there was no significant difference in memory performance (P < 0.01). According to the findings, teachers and clinicians are suggested to consider the importance of circadian rhythm parameters in assessing cognitive function in patients and healthy people. Awareness of individual differences of the morningness-eveningness type can be very effective in designing training programs and preventive health associated matters with each type.

The present study aimed at studying the morningness-eveningness chronotype (MEC) of daily and weekly biorhythm fluctuations in the aggression of preschool children. This was a causal-comparative study. The statistical population was preschool children in Tehran. One hundred children were selected through purposive sampling. They were examined at different times of day (08:00, 10:00, 13:00 and 15:00) and different days of the week (Saturday, Sunday, Monday, Tuesday and Wednesday). The data collection tool used was the MEC questionnaire for children, a behavioral questionnaire for preschool children and a self-report questionnaire about aggression. The data was analyzed using mixed ANOVA. The results showed that the aggressive behavior of pre-school children in the educational environment varies throughout the day and week. Also, the aggressive performance of preschool children in the morning differed from that of mid-session children or evening-type children in the educational environment during the week (P<0.01). The results of the behavioral questionnaire showed that the effect of the group on the level of aggression was not significant, but the effect of the day of the week and time of day was significant.

Most previous studies have shown that the language abilities of children with attention deficit hyperactivity disorder (ADHD) are weaker than normal children. But there is no study that examines the impact of ADHD on all areas of linguistic abilities at the same time. The purpose of this study was to investigate the lack of simultaneous and separately linguistic functions in children with ADHD.
For this purpose, 163 students from the fourth and fifth grades of primary school in the middle of the city were selected conveniently and randomly. Verbal memory, naming speed, verbal fluency, language ability, reading abilities, attention, attention deficit disorder with hyperactivity were assessed.
The results showed that the verbal memory, naming speed, verbal fluency, reading ability, attention at the same time in ADHD children are weaker than normal children (Wilk's λ= 0.153, F(19,143)=41.5, p The research showed that language abilities in children with ADHD are separately weaker than normal children and also language abilities in sum were significantly different between them.

Attention is a significant factor for the learning process, and it may affect the degree and efficiency of student’s learning and their teaching.
Therefore, the present paper aims to examine the effect of the fluctuations in daily and weekly rhythms, and chronotype (morningness-eveningness) on the attention performance of preschoolers. The research’s methodology is a causal-comparative one. The statistical population includes 100 preschoolers in Tehran who were selected by purposeful sampling. They were tested in different hours of day (8, 11, 13, and 15) and weekdays (Saturday, Sunday, Tuesday, and Wednesday).
Findings: The data were analyzed by mixed analysis of variance. The results show that preschoolers’ performance is different for different days of week and hours of day (p The practical implications of these findings for the planning of school schedules are benefit.

Investigations have suggested that people with an obsessive-compulsive disorder have an impaired processing of threatening information and attentional bias toward such stimuli. Meanwhile, according to the important role of disgusting stimuli in the persistence of obsessive-compulsive disorder, more research is needed to evaluate the visual attention of these people with regards to the disgusting stimuli. The choice of proper disgusting pictures for the assessment of visual attentional processes in obsessivecompulsive disorder is yet to be addressed. This research aimed to develop and validate a test serving the above purpose using disgusting and matched neutral pictures.
To this end, 113 paired disgusting pictures which were matched with neutral ones in terms of size, resolution, complexity and background, were selected through a thorough search in the web. Assessment of the external validity of the pictures was performed by five independent psychiatrists and clinical psychologists. As such, 73 neutral and 80 disgusting pictures which met the experts’ criteria were selected. To assess the internal validity, pictures were submitted to 20 subjects with obsessive-compulsive disorder (12 cases with washing rituals and 8 without). Subjects were then asked to evaluate the pictures based on the four dimensions including, valence, arousal, disgusting and threatening load from 1(lowest) to 9 (highest).
The results of discriminant validity evaluation and reliability of measures, indicated that the pictures which were selected in this study as disgusting-neutral pictures are sufficiently valid and reliable.
Pictures which were selected in this study as disgusting-neutral pictures could be suitable for the assessment of visual attention processes in patients with obsessive-compulsive disorder and washing rituals.

According to some international researches, infancy is a period of genesis and evolution for biological and psychological rhythms. While environmental factors play an important role in appearance, stability, and evolution of the rhythms, the family is the most essential factor that influences the regulation of children's biological and psychological rhythms.To test the mentioned research findings, we have conducted a fundamental and applied research, with experimental and control groups, to investigate the influence of Iranian parents on their children's biological rhythms. Our findings approved the above mentioned international research results.The study population was all 3 to 7 year old boys and girls of kindergartens and pre-primary schools in Tehran, among which 118 boys, 112 girls, and their 400 parents were selected by a cluster random sampling method to be studied. Half of the boys and their parents as well as half of the girls and their parents assigned randomly to the experimental group and the other half of the boys, girls, and parents assigned to the control group. In the first stage of research, the correct rhythms patterns were thought to the parents of experimental group and, then, by observing both groups of experimental and control groups of boys and girls on the basis of a researcher-made three-part questionnaire (with 13, 9, & 11 items) in the second stage, the data were collected.The results obtained from the research are the followings:1- The effect of biological rhythms of trained parents on biological rhythms of their children is positive and significant.2- There is a positive and significant correlation between the children's biological rhythms with their parent's biological rhythms.3- The correlation between the parents and children's biological rhythms was not significant when taking the sex factor into account.From the results obtained in this research, one may conclude that parent's behavior patterns affect the children's biological behavior and, therefore, the parents may positively influence their children by acting in a right manner.

The information about the microbiology of root canal treated teeth with persistent periapical lesion is very important, because the main cause of endodontic failure in such cases is persistent infection. The purpose of this study was to determine the occurrence of Enterococcus faecalis in teeth with failed endodontic treatment in an Iranian population. Methods & Materials: Twenty two asymptomatic root-filled teeth with chronic apical periodontitis were selected for retreatment. After removal of the root – filling material, the canal was sampled with paper points. All samples were grown under aerobic condition at 35 ˚c, then the bacterial growth was accurately analyzed. The finding indicated that bacteria were cultivated in 13 of the 22 (%59) teeth examined in the study. Enterococcus faecalis and staphylococcus aureus were the most commonly recovered bacteria. All cultivable bacteria were isolated in pure culture (monoinfection). It seems that some bacterial species (faculative anaerobes) with a special ecological resistance and high penetration ability have an important role in endodontic failures.