In Vitro Cornea Models in Contact Lens Based Ocular Drug Delivery

The development of suitable in vitro release and diffusion models for contact lens-based drug delivery may lead to the establishment of in vitro/in vivo correlations. It is evident that an in vitro model that can reproduce the in vivo results would prevent the disqualification of an otherwise effective drug delivery material or method due to poor release results obtained using unsuitable release models. Conversely, it would also aid in discarding materials with poor properties more efficiently. An overwhelming amount of research has shown that both drug-soaked silicone hydrogel and conventional hydrogel materials are unable to continuously release medication at therapeutic levels. For example, studies have shown that commercially available contact lenses can reach extended drug release for up to 24 hours in vivo while significantly shorter release of the same drug from similar contact lens materials have been observed when tested using current in vitro release models. The lack of appropriate in vitro release and diffusion models that are more representative of the physiological conditions in the eye has provided the impetus for this thesis. The guiding objective of this thesis was to investigate the several well-recognized passive/static in vitro ocular drug release models and to introduce novel dynamic in vitro drug release and diffusion experimental models which may help in explaining the discrepancies between in vitro and in vivo results. To effectively recreate the human eye environment in drug delivery studies, the model needs to consider the limited volume and replenishment of the tear as well as the incorporation of corneal cells. By comparing three in vitro models (i.e., fixed volume, dynamic, and cell), the results presented in this thesis aim to offer a robust, reliable and cost effective testing platform more suitable for assessing the drug releasing capabilities of hydrogel contact lenses. The release results prove the importance of a dynamic release platform for testing contact lens materials by identifying interactions between the drug and lens material that would otherwise be disregarded in the fixed volume model. While interactions between lens and material are important to consider during developement and testing in the experimental model, another important parameter to consider is drug interactions with cells. Prodrugs such as prostaglandins belong to a large group of ophthalmic drugs. These compounds are precursors to ophthalmic drugs that are specifically designed to improve the drug residence time in tear film and enhance the drug uptake by the cell membrane. Within corneal cells, these prodrugs can be metabolized through different pathways into the active form of the drug, before reaching the targeted tissue. By using an in vitro cornea model, it was demonstrated that the 24-hour release of prostaglandin prodrug from a pre-soaked silicone hydrogel was comparable to the daily dose of that ophthalmic drug delivered as an eye-drop. These results emphasized the importance of the presence of cells when characterizing the release of drug-delivery materials, and demonstrated how experimental in vitro models have a significant impact on the outcomes of testing ophthalmic drug delivery materials. It was also further hypothesized in this thesis that a cell-based in vitro cornea model combined with a tear replenishment method to study drug release from a contact lens is better suited for release studies from ophthalmic materials. Through modeling the microfluidics of in vivo tear replenishment and using a curved surface to grow cells, a tear replenishment cell culture system was developed as an in vitro testing platform for ocular drug delivery. Via continuous replenishment of a tear solution analogue over the surface of the cell culture model, results from this work demonstrated yet another important role that a dynamic release model will have in predicting the amount of drug loss from a contact lens into the tear film/lacrimal system. Recreating the geometry of the ocular surface as well as the microfluidics of tear replenishment combined with the incorporation of human corneal epithelial cells in this research proved the potential of drug eluting contact lenses when tested under more realistic conditions. The results and the new models developed in this research project may also help to explain or provide means to investigate the discrepancies between in vitro and in vivo studies

Extended Latanoprost Release from Commercial Contact Lenses: In Vitro Studies Using Corneal Models

Mohammadi, S., Jones, L., & Gorbet, M. (2014). Extended Latanoprost Release from Commercial Contact Lenses: In Vitro Studies Using Corneal Models. PLoS ONE, 9(9), e106653. https://doi.org/10.1371/journal.pone.0106653In this study, we compared, for the first time, the release of a 432 kDa prostaglandin analogue drug, Latanoprost, from commercially available contact lenses using in vitro models with corneal epithelial cells. Conventional polyHEMA-based and silicone hydrogel soft contact lenses were soaked in drug solution ( solution in phosphate buffered saline). The drug release from the contact lens material and its diffusion through three in vitro models was studied. The three in vitro models consisted of a polyethylene terephthalate (PET) membrane without corneal epithelial cells, a PET membrane with a monolayer of human corneal epithelial cells (HCEC), and a PET membrane with stratified HCEC. In the cell-based in vitro corneal epithelium models, a zero order release was obtained with the silicone hydrogel materials (linear for the duration of the experiment) whereby, after 48 hours, between 4 to 6 of latanoprost (an amount well within the range of the prescribed daily dose for glaucoma patients) was released. In the absence of cells, a significantly lower amount of drug, between 0.3 to 0.5 , was released, (). The difference observed in release from the hydrogel lens materials in the presence and absence of cells emphasizes the importance of using an in vitro corneal model that is more representative of the physiological conditions in the eye to more adequately characterize ophthalmic drug delivery materials. Our results demonstrate how in vitro models with corneal epithelial cells may allow better prediction of in vivo release. It also highlights the potential of drug-soaked silicone hydrogel contact lens materials for drug delivery purposes.The funding for this project was provided by a Collaborative Health Research Project grant (jointly funded by NSERC and CIHR)

Investigating Content of Statements’ Information Applies to Financial Performance Evaluation of companies (Evidence from Tehran Stock Exchange)

Purpose- This research aims to study the relationship and effect of economic value added (EVA), return on equity (ROE), retained earnings, return on assets (ROA), cash value added (CVA) and free cash flow (FCF) with stock returns. The population of the research consists of 94 companies accepted in Tehran stock exchange (TSE). Design/methodology/approach- The data were analyzed using Eviews software and at two levels of descriptive and inferential of Pearson correlation coefficient tests and multi-variable regression analysis through step by step method. All hypotheses were confirmed except the relationship between ROA and stock return at 95 percent of confidence level..  Findings- The results of regression analysis indicated that the variable of EVA with -0.231 standard coefficient have the most reverse effect on stock return, the residual profit with the coefficient of 0.172 stood at second rank and free cash flows and EVA respectively with standard beta coefficient of 0.129 and 0.114 were graded third and fourth with positive effect on stock return. Originality/value- The variable of ROA through step by step regression didn’t show meaningful effects on stock return. Then we conclude that the content of statements information significantly explain   financial companies performance. Keywords: Information content, Tehran Stock Exchange, Financial Performance.

Evaluation of factors Affecting the development of cloud-based accounting education and the academic performance of accounting students in Iran

Abstract This study aimed to investigate the factors affecting the development of cloud-based accounting education and the academic performance of students. The method of design is quantitative and the type is descriptive - survey. In order to carry out this research, a questionnaire designed by Omar Akbal Tofiq in 2022 was used to collect data. The validity of the questionnaire was confirmed by content validity using experts' opinions. The reliability of the constructs was assessed through three methods; Cronbach's alpha, composite reliability of each structure, and factor loadings of each item. The statistical population of this research is the students of accounting. For the distribution of the questionnaire according to the similarity of environmental conditions and facilities, universities of the west of Iran including Razi University of Kermanshah, Ilam, and Kurdistan were studied. 92 acceptable responses were received and analyzed from the questionnaire distributed by random sampling method. SMART PLS software has been used to analyze the data. The purpose of this study was to determine the extent of adoption of cloud computing methods in the education of accounting courses and its effectiveness in education programs by the students of universities of Iran by applying the influence of external variables, i.e., human factors, economic and technological factors, and cultural and social factors on the development of cloud accounting education and academic performance of students. The results indicate that human, economic, and cultural factors have a significant positive effect on the development of cloud-based accounting education and student's academic performance. Extended abstract Introduction Today, changes and evolution in information technology are constantly determining changes in the field of higher education worldwide. Effective integration of technology in higher education is increasing to provide qualitative education and preparation of students and teachers to face the 21st century and fully familiarity with evolving technologies (Suzianti & Paramadin, 2021; Yukefallah et al., 2021). This will reduce classroom constraints, and students have more opportunities to communicate with each other. E-learning can have an effective and significant impact on academic performance, achievement, and level of student satisfaction with traditional classroom education, which is one of the most appropriate strategies for optimal use of online (virtual) cloud computing education services. In 2020, the sudden outbreak of Covid-19 surprised people all over the world. During the Corona epidemic, 1.5 billion students in 188 countries had their schools closed. Many countries were forced to adopt online education to ensure continuity of learning when social distancing was unavoidable (McBurnie et al., 2020; Reimers & Scheicher, 2020). Hence, in this situation, virtual education is considered the main strategy for continuing the education of students and a way to prevent the spread of disease and the gap in education in universities and educational centers (Huang et al., 2020). The purpose of this study was to evaluate the factors affecting the education of cloud accounting and its reflection on the academic performance of accounting students in light of the COVID-19 pandemic. The importance of this research arises from the fact that it can identify the factors affecting the development of cloud accounting education that promotes successful usage of online learning systems during and after the COVID-19 pandemic. In addition, this research provides practical insights into the adoption and use of online learning systems in developing countries such as Iran. Theoretical Framework Since in recent years, the use of information and communication technologies has been widely used in organizations, departments, and universities and has presented a wide range of benefits for organizations, especially universities in the e-learning sector; identifying and prioritizing the factors affecting the creation and development of e-learning in universities is of great importance (Bahari & Moody, 2021). Several indices such as infrastructural factors (hardware, software), human, economic, and cultural factors are more effective in the creation, development, and application of this teaching method. Remote education is a new and successful educational method; in order to achieve its high goals, it is necessary to continue, time and improve access to computers and the internet in the whole of society, and also it is necessary that education with short-term planning strengthens the skills of teachers and students in using their programs and media that do not have problems such as unfamiliar with new software. Therefore, these skills improve students' educational performance. E-learning in comparison with traditional teaching has major advantages such as flexibility and elimination of unnecessary and costly movements to participate in training courses. E-learning is also independent of time and space variables (Sahbeigi & Nazari, 2012). The results of several studies (Devi, Ratnoo and Bajaj, 2022; Njugunna, 2021) show that the economic variables of students such as social class, place of residence, and occupation of parents affect their academic performance (Omer & Mohmood, 2018). Cultural and social factors are shared values, norms, and attitudes among people that constitute the beliefs of a society (Apsalone & Sumilo, 2015). Culture is one of the important factors that seem to influence the public acceptance of e-learning services in developing countries (Alajmi et al., 2017). According to Elizabeth brown and Hocutt (2017) cloud-based technologies and services such as Google Drive and Google Apps, which are used in the cloud-based collaborative environment, provide new opportunities for integration between shared platforms and student interaction, and students can interact with teachers and classmates (Huang et al., 2016). Research method This research is a descriptive type, and applicable in terms of purpose, and the type of data in this research for questions test is quantitative. In this research, an electronic questionnaire designed by Omar Akbal Tofiq in 2022 was used to collect data. To examine the theoretical model, a survey with two parts is used. The first part includes demographic questions about students, and the second part includes questions for measuring the structure of models. Each section of the structure is measured using a 5-point Likert scale. The statistical population of the study included all students of accounting. According to the establishment of similar conditions for access to students, understanding the research topic, and finally usable results of analysis, the information of universities of west part of the country including the Razi University of Kermanshah, Ilam, and Kurdistan, which are similar in terms of facilities and environmental conditions, were selected, and finally, after distributing the questionnaire (in person and internet) and using simple random sampling, 92 acceptable answers were collected and analyzed. Smart pls is used to analyze the data. Conclusion This study aimed to investigate the factors affecting the development of cloud-based accounting education and the academic performance of students in Iran. According to the results, human factors; economic and technological factors; and cultural and social factors have positive effects on students' educational performance and the development of cloud-based accounting education. The findings of the research showed that integration of cloud computing technology in the educational environment provides new opportunities that improve teaching and learning, and help the students' self-learning and motivate them to learn by providing flexibility, Students during the learning process will interact with each other, leading to the exchange of knowledge, increasing participation, and improving the educational results, which is consistent with the findings of Musyaffi et. al. (2022). Skill problems and teachers' lack of conformity with online education and lack of familiarity with the virtual environment and its structure, difficulty in evaluating the quality of learning of learners, teachers' resistance to enter the age of technology and change of traditional evaluation methods and finally, increasing the teachers' working hours at the beginning of covid-19 pandemic was observed; therefore, accounting professors and students acquire the necessary skills to use educational tools, devices and systems, hardware and software by passing of time and the movement of education from traditional to online education, which is, as a result, necessary to acquire the skills to use Cloud space and equipment needed for both professors and students to use online teaching, which is in agreement with the results of Atanda Balogun et. al. (2023); Wagiran et. al. (2022); and Khan Al-Badi (2022). In this regard, according to the results of the study, it is suggested that university professors have received training for the use of educational technology and virtual learning methods that can improve the quality of virtual education. This training can include applicable methods for virtual learning, how to use instructional and communication tools, and virtual class management. Also, the production and presentation of high and diverse educational resources and content can help students gain the best results in virtual education programs. The selection of educational resources is also important due to students' needs and variety of educational methods. In addition, using new technologies such as virtual reality, artificial intelligence, and gamification in virtual education programs can provide more attractive and useful methods for students

Investigating the Relationship between Social Responsibility and Earnings Management in Banks through Emphasis on the Moderating Role of CEO Power

Considering the impact of CEO Power on a bank’s performance, CEOs can play a role in social responsibility and earnings management. Given that earnings management in banks can have various effects on other industries and the overall economy, banks tend to practice earnings management more frequently than non-financial organizations. Furthermore, due to a lack of transparency and information asymmetry, banks are required to be more accountable to society than other industries. Therefore, this research aims to investigate the impact of CEO Power on the relationship between social responsibility and earnings management in banks. The research sample comprises 16 banks listed on the Tehran Stock Exchange Market and Iran OTC between 2016 and 2021. These banks were selected to test the research hypothesis. The findings of the study suggest that social responsibility has a significant negative impact on earnings management in banks. This implies that an increase in social responsibility may lead to a decrease in information asymmetry and lack of transparency, resulting in a decrease in earnings management. Furthermore, the findings of the study indicate that CEO power does not play a significant role in moderating the relationship between social responsibility and earnings management in banks.IntroductionIndeed, engaging banks in social responsibility practices is expected to be beneficial for their stakeholders. In this context, stakeholders are often attracted to banks with a good reputation for social responsibility. Therefore, executives may engage in social responsibility activities to gain support from stakeholders, defend themselves against stakeholder activism, manage their business reputation, or protect their own careers. However, executives may also engage in social responsibility activities to manipulate earnings management and hide their self-interest motivations, which leads to agency problems. These agency problems arise when executives take opportunistic actions such as earnings management to maximize their profits, increasing the bank's agency costs. Given the influence of powerful CEOs on a bank’s performance, powerful CEOs play a role in social responsibility and earnings manipulation. Therefore, CEO power is one of the most important determinants affecting managers’ decisions.the current research has several important aspects. First, it extends the literature on the effect of commitment to social responsibility activities on firm earnings management, with a specific focus on the banking sector. Second, the research fills a gap in the literature regarding the role of social responsibility in financial reporting. Previous studies have not provided a clear consensus on whether social responsibility commitment has a positive or negative impact on financial reporting quality. Given the diversity of findings reported by previous studies, more research is needed to focus on understanding how social responsibility commitment can affect financial reporting quality, as proxied by earnings management practices.Does social responsibility affect banks' earnings management? Does CEO power have a significant effect on the relationship between social responsibility and earnings management of banks and strengthen this relationship?Literature Review2.1. Corporate social responsibility and earnings managementTo understand the link between corporate social responsibility (SR) and earnings management (EM), previous studies have proposed two perspectives: the ethical perspective and the managerial opportunism perspective. The ethical perspective assumes that EM is negatively associated with SR, while the managerial opportunism perspective argues that EM and SR are positively related. This leads us to our first hypothesis:H1. There is a significant relationship between SR and EM.2.2. Corporate social responsibility, earnings management and CEO powerGiven the influence of powerful CEOs on bank’s performance, powerful CEOs play a significant role in both SR input and earnings manipulation. Therefore, CEO power is considered one of the crucial determinants affecting managerial decisions. Hence, CEO power may have a moderating effect on the relationship between SR and EM. Accordingly, we propose the following hypothesis:H2. Powerful CEOs moderate the SR–EM relationship. MethodologyThe statistical population of this research consists of banks enlisted in the Tehran Stock Exchange Market and Iran OTC. The data from 16 banks for the period between 2016 to 2021 have been analyzed to test the research hypotheses. The statistical method employed in this study is the regression model of mixed data using panel data approach with a random effects estimation.ResultsThe obtained results suggest that social responsibility has a negative and significant effect on bank’s earnings management. In other words, as social responsibility increases, earnings management in banks is expected to decrease. Furthermore, the results show that the significant relationship between social responsibility and earnings management is not maintained when the adjusting variable of the CEO's power is included. In other words, the CEO's power does not have a significant effect on the relationship between social responsibility and earnings management.Discussion and ConclusionWith an increase in activities related to social responsibility, banks experience a decrease in earnings management. This observation aligns with the ethical perspective and the signaling theory, which suggest that social responsibility can serve as a tool to reduce earnings management. Banks with higher levels of social responsibility not only exhibit greater transparency regarding their social responsibility initiatives and stronger engagement with stakeholders, but they also tend to engage in less earnings management. Additionally, the study found that CEO power does not moderate the relationship between social responsibility and bank earnings management. This finding contradicts the theoretical foundations and the research background, which propose that CEOs may use social responsibility to gain stakeholder support, manage their reputation, and defend against stakeholder activism. Therefore, it is evident that relying solely on CEO power and characteristics may not lead to accurate decision-making in this domain. Shareholders and other financial decision-makers should consider factors beyond CEO power when attempting to moderate the relationship between social responsibility and earnings management

Utilising artificial neural networks for assessing seismic demands of buckling restrained braces due to pulse-like motions

Buckling restrained brace frames (BRBFs) exhibit exceptional lateral stiffness, load-bearing capacity, and energy dissipation properties, rendering them a highly promising choice for regions susceptible to seismic activity. The precise and expeditious prediction of seismic demands on BRBFs is a crucial and challenging task. In this paper, the potential of artificial neural networks (ANNs) to predict the seismic demands of BRBFs is explored. The study presents the characteristics and modelling of prototype BRBFs with different numbers of stories and material properties, utilising the OpenSees software (Version 2.5.0) for numerical simulations. The seismic performance of the BRBFs is evaluated using 91 near-fault pulse-like ground motions, and the maximum inter-storey drift ratio (MIDR) and global drift ratio (GDR) are recorded as a measure of seismic demand. ANNs are then trained to predict the MIDR and GDR of the selected prototypes. The model’s performance is assessed by analysing the residuals and error metrics and then comparing the trend of the results with the real dataset. Feature selection is utilised to decrease the complexity of the problem, with spectral acceleration at the fundamental period (T) of the structure (Sa), peak ground acceleration (PGA), peak ground velocity (PGV), and T being the primary factors impacting seismic demand estimation. The findings demonstrate the effectiveness of the proposed ANN approach in accurately predicting the seismic demands of BRBFs.This work was partly financed by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/04029/2020, and under the Associate Laboratory Advanced Production and Intelligent Systems ARISE under reference LA/P/0112/2020

Cataract Surgical Coverage in Kurdistan, Iran

This is a Letter to the Editor and does not have an abstract. Please download the PDF or view the article HTML

Root Canal Anatomy and Morphology of Mandibular First Molars in a Selected Iranian Population: An In Vitro Study

Introduction: The aim of this study was to evaluate root canal anatomy of mandibular first molars (MFM) in a selected Iranian Population using clearing technique. Methods and Materials: A total of 150 extracted MFMs were cleared. The root canal morphology (including the root numbers and root length) and the anatomy of the root canal system (including is the number and type of canals based on Vertucci’s classification, canal curvature according to Schneider's method and the presence of isthmus) was evaluated using the buccolingual and mesiodistal parallel x-rays and stereomicroscope. The data were analyzed using the chi-square test. Results: Two and three roots were present in 96.7% and 33% of the teeth, respectively (P=0.0001). All the teeth (100%) had two canals in the mesial root, while 61.3% of the samples had one distal root canal (P=0.006). The root canal configuration in the mesial canal included type IV (55.3%) and type II (41.3%) (P=0.0001). In doubled-canalled distal roots, 68.8% and 24.3% were type II and type IV, respectively (P=0.0001). Isthmii were observed in 44.6% of mesial and 27.3% of distal roots (P=0.0001). Conclusion: The notable prevalence of type IV configuration in both roots of mandibular first molars, presence of isthmus and root curvature, necessitates the careful negotiation and cleaning of all accessible canal spaces.Keywords: Iranian Population; Mandibular First Molar; Root Canal Anatomy; Root Canal Morphology; Tooth Clearin

A Randomized Clinical Trial of Using Niosomal Zinc Sulfate Plus Cryotherapy in Comparison with Placebo Along with Cryotherapy in Treatment of Common Wart

Background: There are different treatment modalities for common warts and all of them have side effects. Niosomal drug delivery systems have increased efficacy by enhanced transport of therapeutic agents through stratum corneum with decreased side effects. In this study, we assessed the efficacy of combined 2% niosomal zinc sulfate cream plus cryotherapy compared with combination of placebo plus cryotherapy. Methods: Sixty patients with verruca vulgaris enrolled in this randomized clinical trial study. Patients were divided in 2 groups. Group A received 2% niosomal zinc sulfate cream and group B received placebo twice a day. Also, patients in both groups were treated with cryotherapy (liquid nitrogen) every other week. Treatment protocols continued for a maximum of 3 months or until total clearance of the lesions. Results: Mean number of the sessions for complete remission was 4.5±1.38 in group A and 5.36±0.88 in group B and the difference between the two groups was statistically significant. Complete remission was observed in 60% in group A compared with 43.3% in group B that was not statistically significant. Conclusion: Combination therapy with niosomal zinc plus cryotherapy can lead to faster and greater percentage clearance of the lesions without significant increase in adverse effects in comparison with cryotherapy plus placebo