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The study's purpose was to investigate the mediating role of attachment to peers in the relationship between attachment to parents and the social maturity of student adolescents. The research descriptive method was the correlation. The statistical population consisted of 3553 male and female students at the age of 16-18 years old from zone one in Tehran city based on the Krejcie and Morgan' table and by random selection based on convenience method, 334 people selected as the sample, including the fall. The research data gathered using the revised inventory of attachment to parents and peers by Armsden & Greenberg (1987) and the Social Maturity Scale by Nalini Rao (1973). Data analyzed using the Pearson correlation coefficient, stepwise multivariate, and hierarchical regression tests. The results showed the relationship between parental attachment and social maturity was significant and conversely, the relationship between peer attachment and social maturity was not significant. The findings also showed that peer attachment had no mediating role between parental attachment and social maturity. Therefore, although peer attachment did not play a mediating role between social maturity and parental attachment, the findings of this study showed that attachment to parents was more crucial in determining adolescents' social maturity than attachment to peers.

The present study developed the revised version of the Parent-Adolescent Conflict Issues Checklist (PACIC) by completing the judgment stage of systemic content validity. In the first study, to examine the necessity and relevance of each item, 40 experts were selected through a purposeful method. After the judgment stage, 92 items were reduced to 47 items and 13 factors. In the second study, to assess the confirmatory factor analysis, adolescent girls and boys aged 12–18 years completed the checklist ( N = 1350, mean age 15.4 years, girls 50.1%); also, the Youth Self-Report Scale (YSR), Adolescents' Perceived Family Collective Efficacy Scale (EFCP/A), and the Conflict Behavior Questionnaire (CBQ) were applied to assess concurrent validity, and to establish convergent validity, respectively. The obtained results supported the reconstructed model, and the items went well with the specified factors. The study achieved concurrent and convergent validity. The Cronbach’s alpha coefficients between 0.78 and 0.86 showed that this instrument has excellent internal consistency; moreover, PACIC-R has measurement invariance across gender; thus, PACIC-R can be applied to assess the issues of parent-adolescent conflict and the challenges of families as well.

Background: Adolescence is defined as a period with multiple and intertwined physical, psychological, and social developments during which risky behaviors increases. Various factors affect the tendency and occurrence of risky behaviors. Time perspective (TP) is defined as the role of time and attitude toward time in affairs and behaviors. Executive functioning skills allow an individual to perceive stimuli from his or her environment, respond adaptively, flexibly change direction, anticipate future goals, consider consequences, and respond in an integrated or commonsense way. Objectives: This study aimed to predict risky behaviors based on TP in Iranian adolescents by emphasizing the mediating role of decision making and inhibitory response. Materials and Methods: Path analysis was used to evaluate the relationship between components of TP and risky behaviors with mediator variables, decision making, and inhibitory response among 804 high school adolescent students (including 470 males and 334 females) in Sanandaj, Iran. All participants were asked to complete the Iranian Adolescent Risk Scale and Time Perspective Scale and perform 2 computer tasks [i.e., Go/No-Go and Balloon Analogue Risk Task (BART)]. Statistical methods were descriptive statistics, correlation test, as well as path analysis. Also, the bootstrapping procedure was used. The output provided a 95% CI of the indirect effects. SPSS version 26 and AMOS version 24 were used to analyze direct and indirect relationships. Results: There was a significant relationship between the components of TP and the tendency to risky behaviors. Risky decision-making and inhibitory response had a significant effect on 3 aspects of TP in predicting adolescents’ risky behaviors. These effects were both direct and indirect, of which the former effect was created by mediating the decision-making and inhibitory response. Conclusions: The components of TP, decision-making, and inhibitory response predict risky behaviors in adolescents.

The effects of total ionizing dose on 3-D flash memories irradiated with gamma rays are investigated. The evolution and shape of threshold voltage distributions are studied versus dose for floating gate cell NAND arrays with vertical-channel architecture. The dependence of total dose effects on the logic level stored in the cells, the underlying mechanisms, and the raw bit errors induced by gamma-rays are discussed. The results are then compared with planar NAND and NOR flash technologies, in terms of threshold voltage shifts and bit error rates, showing improvements over previous generations due to the new cell structure.

Airborne pollen is considered one of the causative agents of hay fever, allergic rhinitis, conjunctivitis, and asthma. We aimed to investigate airborne pollens in the context of Shiraz located in the southwest of Iran and find their association with meteorological parameters. The survey was conducted from October 2017 to September 2018, using seven days of volumetric Burkard spore trap, located in the center of the city. A total of 5810 pollen grains/m3 belonging to 15 taxa were identified and recorded. Among them, 73.8% was the tree, while the grass, shrub, and weed constituted 13.56%, 3.5%, and 9.2% of total reported pollens, respectively. The major pollen types were Platanaceae (28.39%), Oleaceae (21.17%), Pinaceae (15.11%), Amaranthaceae (9.29%), and Brassicaceae (8.02%). A higher number of pollen counts and types were recorded in March, followed by September, while it was lower in May. Meteorological parameters were correlated with the monthly pollen counts. Wind speed was found to have a positive correlation with Platanaceae concentration. The significant correlation between pollen concentration and the temperature was positive for Poaceae, Amaranthaceae, and Plantaginaceae and negative for Rosaceae, Oleaceae, and Ulmaceae. Poaceae and Amaranthaceae were negatively correlated with humidity and positively with Rosaceae, Oleaceae, and Plantaginaceae. A negative correlation was found between rainfall and Poaceae and Amaranthaceae, while Plantaginaceae had a positive correlation with this parameter. The results of this study may be helpful for allergologists in the diagnosis and treatment of airborne allergic disorders due to pollen grains.

Studies have shown that the global climate has been dramatically changed during last decades. The results of the investigations have shown that enhancement of greenhouse gases due to human activities is one of the main factors of climate change in the present century. CO2 is one of the most important greenhouse gases, which has begun to increase rapidly since the mid-19th century. Studies have shown that carbon dioxide concentrations have risen by about 43% from 277-280 ppm since the late 1700s and now the concentration of this gas is close to 400 ppm (Samenow, 2013). According to scientists, carbon dioxide is responsible for 61% of the total global warming. In addition to the harmful effects of increasing the carbon dioxide concentration and global warming, this gas has a positive effect on agriculture, which increases its importance. The results of the research indicate that increasing CO2 concentration causes photosynthesis enhancement also by increasing the photosynthesis dry matter weight increase, and consequently the amount of production increases (Semenow et al., 2012‎). Rogers et al., (1994), indicated that doubling carbon dioxide concentration has led to an increase in plants’ yield approximately by 33%. In addition, environmental conditions such as light, temperature, water and available nutrients, moisture, etc., and the interaction between them, overwhelms the effect of plants on changes in carbon dioxide concentration.

The effects of heavy-ion irradiation on 3-D NAND flash memory cells are investigated. Threshold voltage distributions are studied before and after exposure, as a function of the linear energy transfer, fluence, and irradiation angle. Shifts are smaller in 3-D devices than those in planar ones, for the same equivalent bit density. The cell circular shape and the fact that the tunnel oxide and interpoly dielectric blocking layers are perpendicular to the semiconductor substrate make it possible to gain insight into the underlying upset mechanism, which cannot be obtained with planar devices. Evidence that energy deposition in the blocking oxide layer can contribute to charge loss from the floating gate is presented.

Broad-beam and microbeam single-event effect tests were performed on metal–insulator–metal capacitors with three different thicknesses of silicon nitride (Si3N4) dielectric insulator: 250, 500, and 750 nm. The broad-beam tests indicated that the devices with the thicker, 500- and 750-nm dielectric did not have a greater breakdown voltage. The surrounding structures of the capacitor were suspected to be a possible cause. Microbeam techniques made it possible to localize the failure location for the 500- and 750-nm devices. The failure occurs in the air bridge structure connected to the top capacitor plate, which can therefore be considered as an edge effect, while for the 250-nm devices, the failure occurs in the body of the capacitor.

Climatic phenomena play a significant role in development of the tourism industry. An appropriate climate may bring positive responses of tourists. The tourists plan their journeys considering the climatic and weather conditions of their destination. Chaharmahaland Bakhtiari Province is a mountainous region in west of Iran which enjoys various distribution of climatic elements especially rainfall and temperature due to topographic diversity. Statistical methods of factor analysis and cluster analysis were applied to obtain a precise recognition about the climatic zones of the province. 26 climatic variables were selected from six existing weather stations in the province. The results obtained from factor analysis showed that province climate is affected by four climatic factors which are listed here in order of significance: rainfall factor, serene sky factor, thermal factor and humidity factor. Then, four climatic regions were distinguished in the province by means of cluster analysis that was administrated on matrix of factor grades. At last, using PET index, evaluation and comparison were carried out for climate comfort at stations representing each climatic region during a year. The results revealed that May was the best month in terms of climate comfort conditions. Thermal stresss began from June and reached their peaks in July and August. Boroujen and Kouhrang stations entered the climate comfort range in September while same conditions happened for Shahr-e-kord and Lordegan in October.

Water and fertilizer are the most important inputs for producing agricultural crops. Simulation models that quantify effects of water and fertility on yield at the farm scale are valuable tools in water and irrigation management. The AquaCrop model, which has recently been developed by FAO, predicts crop productivity and water requirement under water and fertility stress conditions. In this research, capability of AquaCrop model in simulation of Corn yield response to different levels of water and fertility was studied in Karaj. A field experiment was carried out in 2008 and 2010 years. A factorial design based on randomized complete block design accomplished with four levels (60, 80, 100, and 120%) of the irrigation water requirement and four levels (0, 60, 80 and 100%) of the recommended fertilizer value. Sensitivity analysis showed that the model was sensitive to initial moisture content, time from sowing to start senescence, Reference harvest index (HIo), normalized water productivity (WP*) and maximum coefficient for transpiration (KcTr) more than other parameters. Results showed that the AquaCrop model was able to simulate the grain yield under water and fertility stress, in both years. The normalized maximum error (ME), normalized root mean square error (nRMSE) and coefficient of determination (R2) were calculated 24.77, 9.27 and 0.92 respectively, in validation year. The model was able to simulate the grain yield and crop evapotranspiration (ETC) in non-water stresses (ME, nRMSE an R2 were 9.9, 6.21 and 0.97, respectively) and non-fertility stresses (ME, nRMSE an R2 were 9.9, 6.21 and 0.97, respectively) satisfactory, but it was not satisfactory in simulating sever irrigation and fertility stress. Most deviations from observed data in severe water treatments (ME, nRMSE an R2 were 24.72, 16.61 and 0.66, respectively) occurred.