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Background: Bullying among adolescences is known as a public health abnormality and studying the prevalence of bullying behaviors using different methods of data gathering can help researchers in surveillance and planning preventions. Objectives: The objective of this study was to compare the prevalence of perpetration and victimization of bullying reported by self-report, peer-report, and principle-report. Methods: In this cross-sectional study that was conducted in 2017 - 2018, a total of 1,540 students from 42 schools throughout Mazandaran province completed self- and peer-report questionnaires and 42 principals of 42 schools completed a principal-report questionnaire. The chi-square test was used to compare the prevalence of victimization and perpetration of bullying with self-report, peer-report, and principal-report methods across gender, school types and grade levels. Results: The prevalence of bullies and victims in self-, peer-, and principal-report methods were different (20.2% as victim and 7.8% as a bully for self-report, 9.4% as victim and 8.9% as a bully for peer-report, and 4.3% as victim and 3.1% as a bully for principal-report). Conclusions: This study showed the discrepancy in the prevalence of perpetration and victimization of bullying reported in three measurement methods (self-, peer-, and principal-report) in Iranian schools and suggests the use of multiple assessment methods for bullying behaviors.

The aim of the current study was to examine the structural relationship between hopefulness and academic achievement with the mediating role of academic procrastination among students. The participants included 150 second grade middle school male students who were chosen through multistage cluster sampling method. Solomon and Rothblum’s academic procrastination scale and Snyder’s hope scale were administered. Structural equation modeling (SEM) and Bootstrap tests were conducted to explore direct and indirect pathways of the study model respectively. The results showed that hopefulness and academic achievement are antecedents and consequences of academic procrastination among students respectively. The results indicated that academic procrastination has a significant mediating role on the relationship between hopefulness and academic achievement. The findings of this study could help school counselors, education psychologist, and teachers to reduce students’ procrastination and academic problems.

Recycling and upgrading of low-grade materials plays a pivotal role in building a sustainable circular bioeconomy. The present study explored the potential of energy recovery from biorefinery landfills by means of in-situ thermal processing of municipal solid waste (MSW) with a techno-economic analysis and using RETScreen clean energy project analysis software. An environmental assessment was performed to validate the sustainability of the proposed process. The biorefinery landfill uses existing MSW landfill infrastructure to move from a disposal-only paradigm to a product-creation paradigm. This innovative concept can reduce the extra costs of ex-situ conventional power plants by avoiding waste transportation to a secondary site. A case study in Atlantic Canada was employed to optimize energy reclamation from MSW via two principal pathways: (1) Rankine cycle steam power plant and (2) gas turbine. A plant with a 30 t h−1 capacity and 2 MW power production was proposed as a base case. The results indicated that the gross reduction in annual greenhouse gas emissions was 1115 t CO2 greater for a gas turbine than a steam cycle. Further, for a steam power plant, the capital cost was approximately three-fold higher, and the operating and maintenance costs were nearly eight-fold higher than a gas turbine plant. Study results will encourage progress towards a sustainable biopower system and lay the foundation for comprehensive analysis of renewable resources like MSW. The key outcomes of this study target growth of the circular bioeconomy. Moreover, they can serve as the basis to draw recommendations on the techno-economic feasibility of implementing such biorefineries, specifically at high latitudes where energy costs are relatively high.

This study compared parental and school bonding in adolescents in Iran who are perpetrators of bullying, victims of bullying and not-involved in bullying. Secondary school students ( N = 240) were selected by cluster random sampling and screening, and categorized as perpetrators of bullying ( N = 80), victims of bullying ( N = 80) and non-involved ( N = 80) by teacher and vice-principal nominations. The Parental Bonding Instrument and the School Bonding Scales were completed by the students. With some exceptions (i.e., no between-group differences in maternal overprotectiveness and boys reported higher levels of school involvement than girls), results suggest similar patterns in Iran as in Western societies. With regard to parental bonding, perpetrators of bullying reported lower levels of maternal and paternal care than victims of bullying and non-involved students, higher levels of paternal overprotectiveness than non-involved students, higher levels of paternal authoritarianism (or lower levels of autonomy) than victims and non-involved students, and higher levels of maternal authoritarianism than victims. For school bonding, perpetrators of bullying reported lower levels of school and teacher attachment than the other two groups and victims reported lower levels of school and teacher attachment than non-involved students. Implications for school psychologists are discussed.

In this research, the effects of a solidification/stabilization (S/S) technique on the remediation of cresol-contaminated soil were investigated. The soil samples were collected from the Tehran Oil Refinery (TOR) in Ray District, Iran. Cresols are hazardous chemicals whose exposure at high dosage results in irreparable damage to animal and human health. S/S process progresses through physicochemical reactions, reducing the leachability of a waste as well as changing its physical properties in order to encapsulate the contaminants and form a solid material. The samples were spiked by certain concentrations of cresols including meta-, ortho-, and para-isomers. The treatment process was conducted using Portland cement as the binder and modified bentonite as a stabilizer. The efficiency of the S/S technique was assessed by the unconfined compressive strength (UCS) test and toxicity characteristic leaching procedure (TCLP) test. The results of the tests showed that adding 20% and 30% Portland cement in combina...

The unburned carbon (UC) content of fly ash impacts the performance (e.g., air entrainment, rheology) of concrete mixtures. The loss on ignition (LOI) test is commonly used to estimate the UC content; however, this may be inaccurate, as the weight change upon igniting fly ash is also due to calcination of carbonates, desorption of bound water, and oxidation of sulfur and iron minerals. In this study, a two-atmosphere thermogravimetric analysis (2A-TGA) coupled with mass spectrometry (MS) was performed to evaluate the chemical reactions that occur upon heating of fly ash and to measure the true UC content. 2A-TGA was performed under two distinct atmospheres: (i) in non-oxidizing helium gas, to measure weight loss due to decomposition of carbonates and loss of bound water and (ii) in oxidizing air, to measure weight loss due to conversion of UC to carbon dioxide (CO2). The method was applied to five class F fly ashes with LOI in the range 1.89 % to 7.66 %, a class C fly ash (LOI = 3.86 %), and a fluidized bed combustion (FBC) ash (LOI = 8.10 %). The results were also compared with the total carbon (TC) of each fly ash measured using infrared (IR) spectroscopy via a commercial Laboratory Equipment Corporation (LECO) carbon analyzer. The results show that there is no one-to-one relationship between the LOI and the TC or UC contents of fly ash. LOI overestimated TC by up to 2.5 times and overestimated UC by up to 6.4 times.