Search

The objective of this study is to examine the impact of corporate social responsibility (CSR) initiatives of a firm as one of the critical factors to improve the competitiveness of the firm in today’s aggressive market environment. The influence of corporate social responsibility on brand loyalty and brand image, which distinguishes the firm from other competitors, was evaluated in the study. Data from 364 consumers were collected through adapted and structured questionnaires for the period from August 2018 to December 2018. The respondents were selected through convenience sampling to generate the responses of individual online consumers who buy luxury goods online. The sample size of 364 was taken from a simple random table with a 5% margin of error and a 95% confidence level. SEM-based multivariate approaches such as structural equation modeling and confirmatory factor analysis were employed, and SmartPLS 3.0 software was used for the data evaluation. The results indicate that the firm’s CSR initiatives have a significant and positive impact on brand loyalty and brand image. The study undertaken has several theoretical and practical implications which could provide the basic foundations and conceptual framework for future studies, and it offers strategic directions for the senior managers of firms to plan CSR initiatives that can enhance the brand loyalty of their brands and also increase corporate reputation, all of which are beneficial to remain competitive in today’s business arena.

Background: This study aimed to evaluate the impact of photodynamic therapy (PDT) using two photosensitizers, methylene blue and indocyanine green, on the microtensile bond strength of a universal adhesive to caries-affected dentin. Methods: The occlusal enamel of 60 third molars was cut to expose the inner one-third of the dentin. Artificial caries were induced through a pH cycling process. The samples were divided into three groups: M (Methylene blue+ diode laser), I (Indocyanine green agents+ diode laser irradiation), and control. Each group was further divided into two subgroups according to the adhesive protocol (self-etch, total-etch). After restoring with Gradia composite resin, teeth were sectioned and exposed to 5000 thermal cycles. Microtensile bond strength was measured using a universal testing machine. The data were subjected to two- and one-way ANOVA and paired comparisons were performed by the Tamhane and Tukey tests. Results: The study found significant effects of the photosensitizer, etching pattern, and their interactions on the microtensile bond strength of composite resin to caries-affected dentin (P < 0.001). In the self-etching mode, PDT with indocyanine green exhibited significantly higher bond strength values compared to PDT with methylene blue (P = 0.001) and the control groups (P < 0.001). However, no significant differences were observed in the total-etch mode. (P = 0.54). Conclusions: The etching mode played a more significant role in the bond strength when using the universal adhesive alongside PDT with methylene blue and indocyanine green. Employing two photosensitizers in PDT during the self-etch mode significantly increased the bond strength values.

Interventricular septal dissection is a rare Complication of the interventricular septum. It may result from an aneurysm of the sinuses of Valsalva, bacterial endocarditis, trauma, cardiac surgery, Myocardial infarction, endomyocardial biopsy, or a congenital myocardial developmental anomaly. Postmyocardial infarction ventricular septal rupture (VSR) is a rare complication (1/1000), and ventricular septal dissection is an even less common complication with only five case reports previously described, But unruptured post Myocardial Infarction (MI) dissection is even rarer with only one reported study before. In this case report we describe an unruptured post-MI Interventricular septal dissection following anterior wall MI.

A specific type of mesopore extrudates gamma alumina was prepared; which is applied as the catalyst in the heavy oil hydrodesulfurization unit. Extrudates gamma alumina has been devised the boehmite powder; several samples have been utilized to investigate the concentration and the number of acetic acid treatment effects on the textural properties. Textural properties of catalyst support have been characterized by X-Ray Diffraction, N2-adsorption/desorption techniques, the best results were observed at 25% acetic acid after three times treatments. The active metals (3.71%Molybdenium &1.43%Nickle) have been impregnated on the catalyst support. The prepared catalyst determined by X-Ray Fluorescence, N2- adsorption/desorption, bench-scale reactor test, NH3-Temperature Programmed Desorption and Radial Strength techniques.

A particular type of mesopore extrudates gamma alumina was prepared; which is used as the catalyst in the heavy oil desulfurization unit. Extrudates gamma-alumina support has been made of the boehmite powder from Nephlinsinite mine ores (Surface Area (S.A.) >200 m2/g, Pore Volume (P.V.) =0.48 cm3/g, Average Pore Diameter (A.P.D.) = 8.10 nm); then, many samples of extrudate gamma-alumina (γ-Al2O3) have been created to carry out a research the thermal and ammonia treatments under various operating situations (thermal effect 25,40,60,80 and 100ºC and Consecutive treatments) so as to exhibit the effects of different operating conditions on the pore volume and diameter in the prepared γ-Al2O3 heavy oil catalyst support. Textural properties of catalyst support have been identified by X-Ray Diffraction (XRD), N2-adsorption/desorption, FT-IR, radial strength, and Loss of Ignition (L.O.I) methods. The best effect of the ammonia treatment on the extrudate γ-Al2O3 support was observed after three ammonia treatments at 80ºC; under those circumstances, the resulted catalyst support has the highest amount of resemblance along with the commercial sample (S.A.=215.75 m2/g, P.V.=0.83 cm3/g, A.P.D. =15.49nm).

Introduction: COVID-19 is a pandemic disease caused by a novel coronavirus, presenting a wide range of symptoms. Most of the reported symptoms are commonly related to the respiratory system; however, over time, the disease has shown new diverse signs and symptoms. Recent studies have suggested that COVID-19 may affect the auditory and vestibular systems. Besides, little is known about symptoms that persist after the recovery. This study aimed to investigate the general characteristics and especially auditory and vestibular symptoms in young COVID-19 patients over a 3-month follow-up. Materials and Methods: A total of 300 participants aged 25-45 years took part in this cohort study. They were diagnosed with COVID-19, according to radiographical abnormalities on CT scan and or PCR test, and were in good health based on medical history. Patients who had a history of hearing loss, vertigo, tinnitus, or any disease associated with auditory and vestibular disorders and who were hospitalized and received drugs were excluded. We collected patients’ demographics, some common symptoms, and their complaints (acute phase), and 1 month and 3 months later (follow-up phases) using a checklist of symptoms. The participants were asked to describe their chief complaints and, in particular, whether they had any complaints of hearing problems, tinnitus, rotatory vertigo, and aural fullness, or even changes in these symptoms over these periods. Results: Auditory and vestibular symptoms were observed in a small percentage of COVID-19 patients and were not their chief complaints. Overall, among 300 patients, only about 5% of patients (15 cases) expressed rotatory vertigo, 4% (12 cases) aural fullness, 2.66% (8 cases) tinnitus, and 2.66% (8 cases) hearing problem in the acute phase. However, these symptoms disappeared almost in all participants in the follow-up phases (0 to 3 cases). In addition, none of these symptoms were the patients’ chief complaints. Conclusion: Only a small percentage of COVID-19 patients complained of auditory and vestibular symptoms. It needs to be determined whether these complaints are due to the effects of the virus itself, medications, or stress. The persistence of some symptoms, such as fatigue even after 3 months, indicates the long-term impact of the COVID-19 virus, which necessitates further studies.

In a rational expectation utility optimization model, the consumption profile is smoothed over time and, under some simplifying assumptions, it equals a constant fraction of total lifetime income. For this result to hold, the consumer must be able to transfer income from one period to another. Otherwise, the consumer is under liquidity constraints. The liquidity constraint affects the allocation of durable and non-durable consumption. We focus on the relationship between the marginal utility of household durable good stock and the marginal utility of non-durable consumption. When capital markets are perfect, the marginal utility of these two variables always bears an equilibrium relationship. But if liquidity constraints are binding, the difference between the lagged value of these two variables can predict the current growth change in non-durable consumption. We estimate the long-run relationship between these two variables using an error correction model and a pseudo-panel data set based on Iranian Household Expenditure and Income Surveys (HEIS). In the error correction model, the faster the error of the long-run relationship corrects, the lower the liquidity constraint. This coefficient is estimated to be statistically significant and is in [-0.22, -0.30] range in different estimates, thus we can reject the permanent-income hypothesis and accept that capital markets are not perfect in Iran.

Objectives: Toothpastes and mouthwashes contain chemicals that may be harmful to oral tissues. This study assessed the cytotoxicity and antibacterial activity of toothpastes and compare the Iranian and foreign toothpastes and mouthwashes available in the Iranian market in this respect. Materials and Methods: Twenty samples (13 toothpastes and 4 mouthwashes) were selected. The cytotoxicity of 1, 10, and 50 mg/mL of toothpastes and 0.05, 2 and 10 µL of mouthwashes was measured after 1, 15 and 30 min of exposure to human gingival fibroblasts, each in triplicate. The methyl thiazolyl tetrazolium (MTT) assay was used for cytotoxicity testing. The serial dilution method was utilized to determine the minimum inhibitory concentration (MIC) of each sample against Lactobacillus acidophilus (L. acidophilus) and Streptococcus mutans (S. mutans). Two-way ANOVA and Tukey’s test were used for data analysis. Results: A significant difference in cytotoxicity was noted among different products (P=0.00). The difference in cytotoxicity of each sample was not significant at 1, 15 and 30 min (P=0.08). The obtained MIC for all toothpastes and mouthwashes was between 0.0039 mg/mL and 0.0156 mg/mL, except for Sensodyne toothpaste and Oral B mouthwash. Conclusion: Some brands of toothpastes have higher cytotoxicity due to their composition, and their cytotoxicity should not be overlooked. The antibacterial activity of the samples was almost equal when they were in contact with L. acidophilus and S. mutans except for the Irsha mouthwash, Sehat, Darugar and Bath toothpastes. The antibacterial effect of toothpastes and mouthwashes increased with an increase in exposure time.

A new derivative of Cyclotriphosphazene with xanthydrol as the oxygen-containing ligand was synthesized. Firstly Hexaclorocyclotriphosphazene was obtained Hexaclorocyclotriphosphazene from ammonium chloride and phosphorus pentachloride reaction and then the deprotonated xanthydrol was reacted with Hexaclorocyclotriphosphazene in the ratio of 6:1 in dry toluene as the solvent. All of the Cl atoms were substituted with hydroxyl groups of ligand to give a new product with (NP (C14H10O) 2)3 formula. This product was identified by a series of spectroscopic techniques including FTIR, 31P NMR, 13C NMR, 1H NMR and mass spectroscopy. Analyses were performed to confirm the formation of the designed product and structure.

In this study, we have been involved in the synthesis and characterization studies of a new cyclotriorganophosphazenes complex with protected phloroglusine ligand. Firstly,we synthesized hexachlorocyclotirphosphazene from ammonium chloride and phosphorus pentachloride reaction and then two hydroxyl groups of the phloroglusine ligand were protected with methyl iodide and tosyl chloride. Finally, the deprotonated and protected phloroglusine was reacted as an oxygen-containing ligand with hexachlorocyclotriphosphazene in the ratio of 6:1 in THF as a solvent, All of Cl atoms were substituted with hydroxyl groups of ligand to give a new product. This product identified by a series of spectroscopic techniques including FT-IR,31P NMR, 13C NMR, 1H NMR and mass spectrometry

Introduction: Hearing loss is one of the most common problems in elderly people. Functional side effects of hearing loss are various. Due to the fact that hearing loss is the common impairment in elderly people; the importance of its possible effects on auditory memory is undeniable. This study aims to focus on the hearing loss effects on auditory memory. Materials and Methods: Dichotic Auditory Memory Test (DVMT) was performed on 47 elderly people, aged 60 to 80; that were divided in two groups, the first group consisted of elderly people with hearing range of 24 normal and the second one consisted of 23 elderly people with bilateral symmetrical ranged from mild to moderate Sensorineural hearing loss in the high frequency due to aging in both genders. Results: Significant difference was observed in DVMT between elderly people with normal hearing and those with hearing loss (P