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Abrasive Water Jet Machining (AWJM) is one of the most environmentally friendly non-conventional machining processes, which can be employed to cut hard and thin materials without any thermal effects. In this study, the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) has been combined with the Entropy method and employed to find out the multi-criteria decision-making of process parameters. Experimental investigations have been conducted to evaluate the performance of the AWJM process in terms of surface roughness (Ra) and kerf angle (Ka). The selected process parameters are a stand-off distance (SOD), traverse speed (TS), and abrasive flow rate (AFL), whereas the AL-alloy 2024-T3 was selected as the work piece material. The image process technique has been utilized to measure the values of the Ka. The results demonstrate that the optimal solutions of the AWJM process, which give the smallest value of Ra and minimizes Ka, are 2mm, 20mm/min, and 100 g/min, for SOD, TS, and AFL respectively.

Most of wire drawing processes is performed at room temperature, causing rising up the heat due to the plastic deformation and the generated friction at the work piece-tool interface. In the poor lubrication conditions, there is a likelihood that both the die and the drawn wire will be damaged. This is because the drawing load is greatly influenced by tool geometry and lubrication conditions, The research work conducted in this paper focuses on drawing of 3 mm diameter Electrolytic tough pitch (ETP) cooper wire to perform 20% reduction in cross sectional area through a conical die. Various parameters have been tested to study the effect of them on the forming load during wire drawing including die angle (4°,6°,8°), bearing distance (1.2, 1.5, 1.8) mm, and lubricant types (Lithium-based greases, soap powder, oil HP). The first phase of this paper is conducted to estimate the coefficient of friction for each lubricant type, Utilizing the experimental values of drawing force in theoretical formals. Based on the estimated values obtained, the second phase was creating numerical model to extend the work to more parameters level as well as check the results validation. The results demonstrated that the drawing force increases with increasing of bearing distance and friction coefficient.

In many manufacturing fields such as the aeroplanes and automobiles industries, the control of the thinning variations in produced parts is a major point to investigate since good thickness distribution mean the reliability of these products. In this framework, several experimental and numerical modeling tests have been developed for the purpose of studying phenomenon of thinning during rubber pad forming process. The low carbon steel (AISI 1080) has been used as the blank material. Three forming block shapes had been used (flat, hemispherical and complex), rubber pad with three different hardness (50, 60 and 70 Shore A) also the rubber pad thickness have (40, 60 and 80 mm). The results have showed that improvement in thickness distribution occurred with decrease in rubber hardness and thickness distribution is various from one deformation style to other.

Muhanna M Alshaibani,1 Juriyati Jalil,2 Nik M Sidik,3 Ruangelie Edrada-Ebel,4 Noraziah M Zin1 1Programme of Biomedical Science, School of Diagnostic and Applied Health Sciences, Faculty of Health Sciences, 2Drug and Herbal Research Centre, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Kuala Lumpur, 3School of Bioscience and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia; 4Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland Background: Zingiber spectabile, commonly known as Beehive Ginger, is used as an ethnobotanical plant in many countries as an appetizer or to treat stomachache, toothache, muscle sprain, and as a cure for swelling, sores and cuts. This is the first report of isolation of Streptomyces strain from the root of this plant. Strain Universiti Kebangsaan 25 (SUK 25) has a very high activity to produce secondary metabolites against methicillin-resistant Staphylococcus aureus (MRSA), which is associated with high morbidity and mortality rates due to acquired multidrug resistance genes and causes medication failure in some clinical cases worldwide. Phylogenetic analysis based on the 16S ribosomal RNA gene sequence exhibited that the most closely related strain was Streptomyces omiyaensis NBRC 13449T (99.0% similarity). Aim: This study was conducted to carry out the extraction, identification, and biological evaluation of active metabolites isolated from SUK 25 against three MRSA strains, namely, MRSA ATCC 43300, MRSA ATCC 33591, and MRSA ATCC 49476. Materials and methods: The production of secondary metabolites by this strain was optimized through Thronton’s media. Isolation, purification, and identification of the bioactive compounds were carried out using reversed-phase high-performance liquid chromatography, high-resolution mass spectrometry, Fourier transform infrared, and one-dimensional and two-dimensional nuclear magnetic resonance. Results: During screening procedure, SUK 25 exhibited good antimicrobial potential against several strains of MRSA. The best biological activity was shown from fraction number VII and its subfractions F2 and F3 with minimum inhibitory concentration values at 16 µg/mL and 8 µg/mL, respectively. These two subfractions were identified as diketopiperazine cyclo-(tryptophanyl-prolyl) and chloramphenicol. Conclusion: On the basis of obtained results, SUK 25 isolated from Z. spectabile can be regarded as a new valuable source to produce secondary metabolites against bacteria, especially MRSA. Keywords: Zingiber spectabile, MRSA, SUK 25, cyclo-(tryptophanyl-prolyl), chloramphenicol, HR-MS, NMR

The work aim to study the effect of the blank holder slope angle on deep drawing parameters such as: punch force, strain state and thickness distribution along cup wall of drawn part. 3-D model of cylindrical cup of (40mm) outer diameter, and (0.5mm) thickness from mild steel (1008–AISI), has been developed. Due to the symmetry in the specimen geometry, only one fourth portion of the model needed to be analyzed. A commercially available finite element program code (ANSYS14.0), was used to perform the numerical simulation of the deep drawing operation. The numerical results of this model were compared with experimental results. Four types of blank holder and dies with slope angle (0o, 7.5 o, 15 o, 22.5 o) .the experimental and numerical results show that the required punch force decrease with increase in blank holder slope angle , The best thickness distribution over all zones in produced cup obtained when using blank holder with angle α= 15º.

In this study, we discuss the existence and impact of microplastics in different ecosystems, including water, soil, air, and the human body, as well as the absorption of pollutants into these microplastic particles. Airborne microplastics have been detected in the atmosphere as well as indoors and outdoors. Microplastics in the air, in addition to inherent toxicity, may cause more risks to human health and the environment than virgin microplastics through the absorption of pollutants and chemicals. Due to the widespread use of plastics around the world, the abundance of microplastics in aquatic environments has increased. Microplastics can be ingested by a wide range of marine organisms, so it is possible that contaminated microplastics cause mechanical damage to organisms and there is also the possibility of contamination being transmitted to marine organisms and the marine food web. Accumulation of microplastics in the soil can cause them to be absorbed by plants and transport these microplastic particles and pollutants absorbed by them along the food chain. Highly populated urban centers, industries or large-scale agriculture are the main causes of soil contamination by microplastics. Microplastics can find their way into the food we eat, the water we drink, and even the air we breathe. Researchers were able to find microplastic particles in all human tissues studied.

Background: Radon is a colorless and odorless radioactive gas that is considered a leading cause of lung cancer. Given this need, the main objective of this policy brief was to discuss the need to pay attention to the prevention and control of indoor radon (IRD) in Iran. Methods: To prepare this policy summary, which is similar to a narrative review, scientific reports and studies conducted in Iran over the past two decades were first obtained by searching reliable national and international databases. Then, based on the main results of the above studies, the general level of IRD concentration in the main regions of Iran was determined. Finally, by using the experiences and measures in other countries, necessary recommendations for the prevention and mitigation of IRD were made Results: By evaluating the findings of previous studies conducted in Iran, it was found that the level of IRD in residential and non-residential buildings evaluated in Iran, in most cases, was higher than the global average (40 bq/m3). In addition, in some cases, it was higher than the acceptable level by World Health Organization (100 bq/m3). Conclusion: Based on the findings, it can be concluded that it is very necessary to educate the public, engineers and health and municipal inspectors about the health risks of exposure to radon. In addition, it is necessary to take basic and preventive measures to mitigation radon in homes.

In this study, the sources of microplastics in the environment, the ways of human exposure to microplastics, how to deal with them, and the policies and laws of different countries in this regard are discussed. Most of the microplastic pollution comes from textiles, tires and urban dust, which make up more than 80% of the microplastics in the environment. The human body is exposed to microplastics through eating food containing microplastics, inhaling microplastics in the air, and skin contact with these particles in products, textiles, or in dust. The main route of human exposure to microplastic particles in human diet is food and drink. Microplastics can enter food during food processing, storage, transportation and packaging process. Airborne microplastics are an underestimated hazard, potentially reaching deep into human lungs because they can pass through the defensive respiratory system. Humans may also be exposed to microplastics through skin contact, following the atmospheric fallout, in this case hair follicles, sweat glands or damaged skin are all ways of entry. Some researchers have suggested burning plastics and recovering the resulting energy. Nevertheless, plastic recycling is considered a more efficient solution because this method reduces the amount of plastic waste produced as opposed to burning.

Abrasive water jet machining (AWJM) is one of the most environmentally friendly non-conventional machining processes, which can be employed to cut hard and thin materials without any thermal effects. In this study, the technique for order of preference by similarity to ideal solution (TOPSIS) has been combined with the Entropy method and employed to find out the multi-criteria decision-making of process parameters. Experimental investigations have been conducted to evaluate the performance of the AWJM process in terms of surface roughness (Ra) and kerf angle (Ka). The selected process parameters are a stand-off distance (SOD), traverse speed (TS), and abrasive flow rate (AFL), whereas the AL-alloy 2024-T3 was selected as the workpiece material. The image process technique has been utilized to measure the values of the Ka. The results demonstrate that the optimal solutions of the AWJM process, which give the smallest value of Ra and minimizes Ka, are 2 mm, 20 mm/min, and 100 g/min, for SOD, TS, and AFL respectively. [ABSTRACT FROM AUTHOR]

Most of wire drawing processes is performed at room temperature, causing rising up the heat due to the plastic deformation and the generated friction at the work piece-tool interface. In the poor lubrication conditions, there is a likelihood that both the die and the drawn wire will be damaged. This is because the drawing load is greatly influenced by tool geometry and lubrication conditions, The research work conducted in this paper focuses on drawing of 3 mm diameter Electrolytic tough pitch (ETP) cooper wire to perform 20% reduction in cross sectional area through a conical die. Various parameters have been tested to study the effect of them on the forming load during wire drawing including die angle (4°,6°,8°), bearing distance (1.2, 1.5, 1.8) mm, and lubricant types (Lithium-based greases, soap powder, oil HP). The first phase of this paper is conducted to estimate the coefficient of friction for each lubricant type, Utilizing the experimental values of drawing force in theoretical formals. Based on the estimated values obtained, the second phase was creating numerical model to extend the work to more parameters level as well as check the results validation. The results demonstrated that the drawing force increases with increasing of bearing distance and friction coefficient. [ABSTRACT FROM AUTHOR]

Abstract Forty-nine methanol extracts of 37 species of Malaysian medicinal plants were investigated for their inhibitory effects on platelet-activating factor (PAF) binding to rabbit platelets, using [.sup.3]H-PAF as a ligand. [...]

Paying attention to the issue of the death of authenticity and alienation of man is one of the most important issues that contemporary man is dealing with ignorning it causes that according to Heidegger; The desert is getting wider every day and the gap between self-being and alienation becomes uncontrollable. In order to understand and face this issue logically, in the present research, the meaning and why of alienation from the point of view of two prominent thinkers of the Islamic world and the West, Allameh MuhammadTaqi Ja’fari and Martin Heidegger, were discussed in a comparative manner. The research shows that for Allameh Ja’fari self-estrangement is divided into two types, positive and negative, and positive self-estrangement means placing the "self" in the path of its logical evolution, and negative self-estrangement means exclusive attention to the animal dimension and neglecting the origin and resurrection. they know and from Heidegger's point of view, losing one's understanding of one's existence and the meaning of one's world, being under the control of previous plans, becoming a passive existence, not trying and seeking to understand the meaning of existence, and also becoming a static being and passive; It takes a person out of the orbit of authenticity and true self-being and enters a space called "alienation from oneself".

This study aimed to investigate the effects of different levels of selenium nanoparticles (Se-NPs) and iron nanoparticles (Fe-NPs) on histopathology of the liver in the beluga juvenile, Huso huso. A total of 135 beluga juveniles (with initial weight of 276.4 ± 32.3 g and initial length of 40.0 ± 2.0 cm) were randomly distributed in 27 fiberglass tanks at 9 different treatments with three replicates. Treatments included T1 (control, no added NPs); T2 (1 mg/kg Se-NPs); T3 (2 mg/kg Se-NPs); T4 (100 mg/kg Fe-NPs); T5 (100 mg/kg Fe-NPs + 1 mg/kg Se-NPs); T6 (100 mg/kg Fe-NPs +2 mg/kg Se-NPs); T7 (200 mg/kg Fe-NPs); T8 (200 mg/kg Fe-NPs +1 mg/kg Se-NPs); T9 (200 mg/kg Fe-NPs +2 mg/kg Se-NPs). Before starting the experiment, the fish were adapted to the rearing conditions for one week. The amount of feeding during the rearing period was 2-3% based on the weight and water temperature, and the fish were fed three times a day (8:00, 15:00 and 21:00) for 8 weeks. In order to find the histopathological changes, the livers of six fish from each group (two fish of each replicate) were sampled at the end of the experiment. Samples were dehydrated by routine methods and embedded in paraffin wax. They were sectioned by microtome and stained with H & E. Vacuolar degeneration, necrosis, inflammation, irregular hepatocytes and hemorrhage were the tissue lesions observed in the liver. Given that, T5 (100 mg/kg Fe-NPs + 1 mg/kg Se-NPs) had the lowest liver tissue damage, using 1 mg selenium nanoparticles with 100 mg iron nanoparticles in the diet of farmed beluga is recommended.

Cheese is popular in Iran because of its high nutritional value; therefore, it is necessary to control this product regarding health risk factors, particularly aflatoxin M1 (AFM1). This research reviewed AFM1 in various varieties of cheese in Iran to assess the potential health risks associated with consuming these products for different age groups. In this regard, all accessible papers from different databases were screened between June 27, 2000 and October 10, 2022 b y systematic research and then considering the selection criteria of the studies; finally, 22 articles were selected for the current review. The amount and prevalence of AFM1 were calculated and separated based on the cheese variety, and the sampling location; health risk assessment (HRA), statistical, uncertainty, and sensitivity analysis for AFM1 of cheese for different age groups were performed. The study results for 2143 samples showed that the overall average AFM1 for cheese is 160 ± 175 ng/kg, below the European Commission (EC) regulation (250 ng/kg). AFM1 contaminated 72.42% of all cheese samples, and 13% of these contaminated samples had a higher AFM1 than the EC regulation. Cheese varieties were ranked based on average levels of AFM1 as white pasteurized > traditional > creamy > probiotic > Lighvan, and this ranking was obtained based on sampling locations as market > dairy factories > livestock farms. Based on the HRAs, from the perspective of the liver cancer risk (LCR), the margin of exposure (MOE), and the hazard index (HI) approach, it can be concluded that cheese produced in Iran, in terms of AFM1, particularly for children, poses serious health risks. Accordingly, it is imperative to carefully consider implementing suitable management methods to inhibit the growth of aflatoxin B1 (AFB1) in livestock fodder, and training in sanitary production and processing of dairy products according to world standards is suggested for industrial and traditional cheese producers across Iran.

Background and Objectives: Spiritual coping strategies of patients are influenced by their mood/anxiety symptoms and emotional schemas. Therefore, the present study aimed to develop a conceptual model of spiritual coping in patients with chronic back pain, considering the role of mood/anxiety symptoms and emotional schemas. Methods: The research method was descriptive correlational. The statistical population included all women and men 25 to 55 years old with chronic back pain referring to the orthopedic and neurology clinics of Torbat Heydarieh City, Iran, in 2021-2022, of whom 400 people were selected considering the inclusion criteria using the convenience method. The tools used were the mood and anxiety symptoms questionnaire (MASQ-D30), a brief version of the Leahy emotional schema scale II-(LESS II), and the religious coping scale. The data were analyzed by structural equation modeling by SPSS software, version 24 and LISREL software, version 8.8. Results: The fitted model showed a direct relationship between mood/anxiety symptoms and emotional schemas (β=0.740), an inverse relationship between mood/anxiety symptoms and spiritual coping (β=-0.480) at the significant level of 0.05, and an indirect relationship between mood/anxiety symptoms and spiritual coping through emotional schemas (β=-0.488), which was significant at the 0.05 level. Conclusion: The results of the study supported the mediating role of emotional schemas in the relationship between mood/anxiety symptoms and spiritual coping strategies of patients with chronic back pain. Therefore, developing therapeutic interventions to reduce emotional schemas and improve spiritual coping strategies along with medical treatments is useful in adapting and improving chronic pain sufferers

This study was conducted with the aim of environmental and behavioral pathology of religious education of children. The research method was descriptive and content analysis. Studies show that the foundation of religious education of children is closed in the family and children are the expression of parents' beliefs and behaviors and they are silent but effective teachers of children; Also, school and friends, as formal and informal spaces that complement their personality, are parallel to the phenomenon of cyberspace, environments whose characteristics have a significant impact on their inclination or non-inclination to religious issues; In the behavioral dimension, the findings indicate that harms such as: upbringing, humiliating behaviors, unjustified harshness and discrimination, etc. are among the incorrect methods that can be inflicted on children by those around them. Suggestions: Promoting media literacy of families, raising children's values, creating a bridge between family and school, paying serious attention to attracting committed people and taking care of the expansion without supervision of non-profit schools.