Three essays on social media-based brand communities

The purpose of this thesis is to investigate the notion of brand communities that are established on social media platforms. Social media has changed marketing practices from information acquisition to post purchase behavior; therefore, it is necessary for marketing scholars and practitioners to update our marketing knowledge according to this new changes. This thesis suggests the brand community lens as a proper and legitimate perspective to study marketing and branding activities on social media platforms because the essence of social media is associated with collective and community building. The first paper of this manuscript not only supports the existential possibilities of brand communities on social media but also more importantly it explores the unique aspects of social media that could interact with brand community practices and argue why we should examine brand community in this new context of social media. The first paper conducts an in-depth qualitative study in two rich brand-generated communities on social media and analyzes their brand community elements and practices. The study shows the qualities of brand community elements, structural relationships (McAlexander, Schouten, & Koenig 2002) and value creation practices (Schau, Muniz, & Arnould 2009) within these communities and extract some unique characteristics of the social media based brand communities that differ from their traditional counterparts. The study concludes five unique dimensions that make social media based brand communities (SMBBCs) distinguished from other offline/online counterparts and argues that this is why brand community researchers should treat brand communities on social media differently and study this phenomena separately. We need to update our understanding of brand community to suit the unique aspects of social media. The second and third papers employ a quantitative approach to show how these communities can influence important marketing variables such as brand trust, brand relationship quality, and brand loyalty. These are marketing fundamental goals that are considered as a way to measure social media success in terms of increasing return on investment. These papers depict how different elements and building blocks of these communities on social media interact and influence trust and loyalty. The second paper shows the role of community engagement as a moderator while the third paper provides a big picture of consumer behavior in the context of brand communities that are established on social media. Several important measures such as value creation practices are developed in this paper

Three essays on social media-based brand communities

The purpose of this thesis is to investigate the notion of brand communities that are established on social media platforms. Social media has changed marketing practices from information acquisition to post purchase behavior; therefore, it is necessary for marketing scholars and practitioners to update our marketing knowledge according to this new changes. This thesis suggests the brand community lens as a proper and legitimate perspective to study marketing and branding activities on social media platforms because the essence of social media is associated with collective and community building. The first paper of this manuscript not only supports the existential possibilities of brand communities on social media but also more importantly it explores the unique aspects of social media that could interact with brand community practices and argue why we should examine brand community in this new context of social media. The first paper conducts an in-depth qualitative study in two rich brand-generated communities on social media and analyzes their brand community elements and practices. The study shows the qualities of brand community elements, structural relationships (McAlexander, Schouten, & Koenig 2002) and value creation practices (Schau, Muniz, & Arnould 2009) within these communities and extract some unique characteristics of the social media based brand communities that differ from their traditional counterparts. The study concludes five unique dimensions that make social media based brand communities (SMBBCs) distinguished from other offline/online counterparts and argues that this is why brand community researchers should treat brand communities on social media differently and study this phenomena separately. We need to update our understanding of brand community to suit the unique aspects of social media. The second and third papers employ a quantitative approach to show how these communities can influence important marketing variables such as brand trust, brand relationship quality, and brand loyalty. These are marketing fundamental goals that are considered as a way to measure social media success in terms of increasing return on investment. These papers depict how different elements and building blocks of these communities on social media interact and influence trust and loyalty. The second paper shows the role of community engagement as a moderator while the third paper provides a big picture of consumer behavior in the context of brand communities that are established on social media. Several important measures such as value creation practices are developed in this paper

Production of Bioactive Peptides in Milk Using Two Native Strains of Levilactobacillus brevis

Background and Objective: Milk proteins are precursors of several biologically active peptides. One of the methods of producing these peptides is fermentation using lactic acid bacteria. The aim of this study was to investigate production of antioxidant and angiotensin-I converting enzyme inhibitory bioactive peptides in cow milk fermented by two strains of Levilactobacillus brevis. Material and Methods: Two strains of Levilactobacillus brevis KX572376 (M2) and Levilactobacillus brevis KX572382 (M8) were used in fermentation of low-fat cow milk. Moreover, pH changes, proteolytic activity, water-soluble extract biological activity (antioxidant activity and angiotensin-I converting enzyme inhibition) of the samples and peptide fraction less than 3 kDa were investigated at 24 and 48 h of fermentation (30 °C). Peptide profile of the superior sample was analyzed as well. Statistical analysis was carried out using one-way of variance, Tukey test and SPSS software v.25. Results and Conclusion: The two strains decreased milk pH to a similar level in the first 24 h. Quantities of free amine groups in the samples treated with M2 and M8 strains within 24 and 48 h of fermentation were significantly different (p≤0.05), compared to the control sample. In the first 24 h of fermentation, no difference was observed in the quantity of free amines of M2 and M8 samples. In the second 24 h, further free amine groups were produced due to the activity of M8 strain in milk. Antioxidant activity of the water-soluble extracts of M2 and M8 samples was significantly (p≤0.05) higher than that of the control sample during fermentation. Antioxidant activity in fractions less than 3 kDa did not show significant differences in M2 and M8 samples at 24 and 48 h of fermentation. In the control sample, no antioxidant activity was observed in fractions less than 3 kDa. The highest ACE inhibitory activity in fractions less than 3 kDa of M8 was observed after 48 h. No angiotensin-I converting enzyme inhibition was seen in fractions less than 3 kDa of M2 and control sample. The RP-HPLC peptide patterns of the fraction less than 3 kDa of M8 and control sample were different, which was a justification for the biological activity in this sample. Conflict of interest: The authors declare no conflict of interest

The Effect of Adding Low-Dose Naloxone to Intrathecal Morphine on Postoperative Pain and Morphine Related Side Effects after Cesarean Section: A Double-Blind, Randomized, Clinical Trial

BACKGROUND: Nowadays, spinal anaesthesia is a suitable choice for most elective and emergency cesarean section (C-section) deliveries. AIM: This study aimed to determine the effect of adding low-dose naloxone to intrathecal morphine on postoperative pain and morphine related side effects after C-section. MATERIAL AND METHODS: In the present double-blind, randomised clinical trial, 70 women aged over 18 years, who were candidates for elective medical C-section under spinal anaesthesia were selected and randomly assigned to either the study group or the control group. For spinal anaesthesia, 10 mg of Bupivacaine plus 100 μg of morphine was administered for all patients. However, patients in the study group received 20 µg of naloxone intrathecally; but the patients in the control group only received normal saline as a placebo. After surgery, patient-controlled analgesia (PCA) pump with paracetamol (Apotel®) was connected to each patient. The intensity of postoperative pain in the patients was evaluated and recorded using Visual Acuity Screening (VAS) at 2, 4, 6 and 24 hours after the surgery. The patients were also examined for postoperative nausea and pruritus. RESULTS: Regardless of the groups to which the patients were assigned, a significant difference in pain intensity was observed during the study period (time effect; p < 0.001). Although the intensity of pain was lower in the study group, the difference was not statistically significant (group effect; p = 0.84). Also, there was no group time interaction between pain intensity and the times studied (p = 0.61). The incidence rates of postoperative nausea and pruritus were significantly lower in the study group compared to the control group (p < 0.001). CONCLUSION: According to the results of this study, adding low dose naloxone to intrathecal morphine did not significantly change postoperative pain intensity in the patients undergone elective C-section using spinal anaesthesia; however, significantly decreased the severity of postoperative nausea and pruritus

Estimation Strategies for the Condition Monitoring of a Battery Systemin a Hybrid Electric Vehicle

This paper discusses the application of condition monitoring to a battery system used in a hybrid electric vehicle (HEV). Battery condition management systems (BCMSs) are employed to ensure the safe, efficient, and reliable operation of a battery, ultimately to guarantee the availability of electric power. This is critical for the case of the HEV to ensure greater overall energy efficiency and the availability of reliable electrical supply. This paper considers the use of state and parameter estimation techniques for the condition monitoring of batteries. A comparative study is presented in which the Kalman and the extended Kalman filters (KF/EKF), the particle filter (PF), the quadrature Kalman filter (QKF), and the smooth variable structure filter (SVSF) are used for battery condition monitoring. These comparisons are made based on estimation error, robustness, sensitivity to noise, and computational time.Comment: 18 pages, 16 figures, ISRN Signal Processing, 201

Designing and validation a visual fatigue questionnaire for video display terminals operators

Background: Along with the rapid growth of technology its related tools such as computer, monitors and video display terminals (VDTs) grow as well. Based on the studies, the most common complaint reported is of the VDT users. Methods: This study attempts to design a proper tool to assess the visual fatigue of the VDT users. First draft of the questionnaire was prepared after a thorough study on the books, papers and similar questionnaires. The validity and reliability of the questionnaire was confirmed using the content validity index (CVI) beside that of the Cronbach's Coefficient Alpha. Then, a cross-sectional study was carried out on 248 of the VDT users in different professions. A theoretical model with four categories of symptoms of visual fatigue was derived from the previous studies and questionnaires. Having used the AMOS16 software, the construct validity of the questionnaire was evaluated using the confirmatory factor analysis. The correlation co-efficiency of the internal domains was calculated using the SPSS 11.5 software. To assess the quality check index and determining the visual fatigue levels, visual fatigue of the VDT users was measured by the questionnaire and visual fatigue meter (VFM) device. Cut-off points were identified by receiver operating characteristic curves. Results: CVI and reliability co-efficiency were both equal to 0.75. Model fit indices including root mean of squared error approximation, goodness of fit index and adjusted goodness of fit index were obtained 0.026, 0.96 and 0.92 respectfully. The correlation between the results measured with the questionnaire and VFM-90.1 device was-0.87. Cut-off points of the questionnaire were 0.65, 2.36 and 3.88. The confirmed questionnaire consists of four main areas: Eye strain (4 questions), visual impairment (5 questions) and the surface impairment of the eye (3 questions) and the out of eye problems (3 questions). Conclusions: The visual fatigue questionnaire contains 15 questions and has a very remarkable validity and reliability. Usingthis questionnaire and its findings, one will be able to identify, assess and finally prevent the effective factors of VDT users' visual fatigue

Antibiotic resistance, virulence and genetic diversity of Klebsiella pneumoniae in community- and hospital-acquired urinary tract infections in Iran

Klebsiella pneumoniae is among the most important causes of urinary tract infection (UTI). The aim of this study was to investigate the prevalence and correlation of antibiotic resistance with virulence characteristics and genetic diversity in K. pneumoniae isolated from UTIs in Iran. Phenotypic tests and antibiotic susceptibility were carried out on the isolates. Detection of the virulence and extended-spectrum β-lactamase (ESBL) genes was performed by polymerase chain reaction. Pulsed-field gel electrophoresis (PFGE) was used for exploring the genomic relatedness. Hemolysin, biofilm, and hypermucoviscosity formation were observed in 87.1%, 86.4%, and 12.1% of isolates, respectively. The antibiotic resistance rate of K. pneumoniae isolates ranged from 12.1% for meropenem to 100% for amoxicillin. The prevalence of virulence genes ranged from 1.4% for cnf-1 to 100% for mrkD, fimH, kpn, and entB genes. In this study, 91.7%, 33.3%, and 4.2% of phenotypically ESBL-producers were positive for blaCTX-M, blaTEM, and blaSHV genes, respectively. An association was observed between the presence of traT, fyuA, or cnf-1 genes with antibiotic resistance. Two clone types were obtained by PFGE that indicate different K. pneumoniae clones in community- and hospital-acquired UTIs. The findings of this study are valuable in development of treatment strategies against UTIs in Iran