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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of School Administration
- نوع مقاله: Journal Article
- کلمات کلیدی: Performance,appraisal,evaluating the performance,evaluating
- چکیده: با توجه به نقش برجستۀ رهبری و مدیریت در عرصۀ دستیابی به اهدف سازمانها، به ویژه مدیران مدارس در نظام آموزش و پرورش، توجه به عملکرد آنان و ارزیابی این عملکردها اهمیت بسیاری دارد. از این رو پژوهش حاضر با هدف ارائۀ مدل مفهومی برای ارزیابی عملکرد مدیران مدارس انجام شد. روش پژوهش کیفی و از نوع فراترکیب بود. گردآوری دادهها به روش اسنادی و با بررسی تمامی منابع علمی مرتبط با موضوع ارزیابی عملکرد مدیران مدارس (1380-1398داخلی و 19990-2019 خارجی) انجام شد. بدین منظور، کلیدواژههای مربوط به دو دهۀ اخیر، از جمله: ارزشیابی و ارزیابی عملکرد مدیران، وظایف مدیران، استانداردهای عملکردی مدیران، ویژگیهای و شایستگیهای مدیران و صلاحیتهای حرفهای مدیران (مدارس) در پایگاههای داخلی نظیر پایگاه اطلاعات علمی؛ اس آی دی، و پایگاه دادههای خارجی همچون گوگل اسکولار، اسکوپوس، امرالد، الزویر، پروکوئست اشپینگر تیلور و فرانسیس بررسی شد. با بررسی کامل 47 منبع از 1123 منبع اولیه، 8 مؤلفۀ اصلی و 28 زیرمؤلفه به عنوان ملاکهای ارزیابی عملکرد مدیران مدارس، شناسایی و طبقهبندی شد. نتایج حاصل از این بررسی نشان داد که توجه به ابعاد شناسایی شده، میتواند به مدیران ارشد در تشخیص دقیق و همهجانبۀ عملکرد مدیران مدارس، کمک کند و زمینۀ تصمیمگیری بهینه، گزینش و انتخاب صحیح آنها را فراهم کند.
- چکیده انگلیسی:
Considering the prominent role of principals in achieving the goals of organizations, especially school principals, it is very important to pay attention to and evaluate their performance. Therefore, the present study aims to provide a conceptual model for evaluating the performance of school principals. The research method is qualitative and meta-combined. Data collection was done by documentary method and by reviewing all scientific sources related to the subject of evaluating the performance of school principals (domestic 1380-1398 and foreign 1990-2011). To this end, in the last two decades, the keywords of evaluating and evaluating the performance of principals, duties of principals, performance standards of principals, characteristics and competencies of principals and professional competencies of principals (schools) in internal databases such as scientific database; SIDs, and external databases such as Google Scholar, Scopus, Emerald, Elsevier, Proquest Spinger Taylor, and Francis were examined with a complete review of 47 sources from 1123 primary sources, 8 main components, and 28 subcomponents as criteria for evaluating school principals' performance. , Identified and classified. It is noteworthy that the findings of this study as a model after going through seven steps of meta-combination and screening of backgrounds and resources obtained, finally by examining 47 sources, the components of school principals' performance evaluation were obtained. Also, after analyzing the components into 28 components and 8 dimensions, which include "Educational Leadership", "Organizational Management", "Resource Management", "Communication Management", "Professional Management", "Ethical Management", "Students' Academic Achievement" And "Client Satisfaction" were categorized.
Educational Leadership < /em>: Educational leadership is an effective process of guiding the talents and energy of teachers, students and parents in achieving common educational goals, whose role is to support, strengthen and help, and ultimately cooperate with members of the organization to improve and develop education in schools. In this study, educational leadership refers to a set of core responsibilities of school principals, namely guidance and leadership, teaching learning, vision definition, professional development, motivation, support, cultural education and improving the school climate.
In the role of leadership, school principals direct the activities of staff or teachers and students in order to achieve the goals of the organization, and also teach and teach them, which is the most important task of school principals, to develop students and to develop the professional profession of teachers. . In order to achieve the goals of the organization, it draws a common vision that is clear to all members of the organization and creates a common understanding of it for teachers, staff and parents. In the motivating role, it recognizes and understands the needs, behavior and personality of students, teachers and staff and guides the behavior towards the desired behavior based on feelings of respect, value, positive self-concept, cognition, self-awareness, justice and understanding the talents and strengths of individuals. Also, in the role of support, it should be the source of solving the problem and opening the work knot of teachers, staff and students. In this sense, the principal is responsible for providing the necessary information, favorable contexts and opportunities to solve the problems of teachers and students, and in the role of educational and cultural affairs, the director cooperates with extracurricular activities that are outside the official programs related to educational and cultural issues. The principal works with a foster care teacher in the school with the aim of protecting the boundaries of belief and preserving the achievements and explaining the values of the country, as well as the development of students' social skills. The school atmosphere is a relatively stable quality of the school environment that is created through the relationship between principal and teachers, teachers and teachers, teachers and staff, teachers and students, or relationships between students, and is based on a collective perception of school behavior. Other schools are distinguished in terms of the effect that the school atmosphere has on the success and performance of the school should be given serious attention by school principals, and the principal in this role should seek to create a joker and effort and intimacy and camaraderie in the school.
Organizational management: Organizational management refers to the general duties of principals in schools. In this model, the set of functions of managers, namely planning, organizing, coordinating, monitoring and controlling, decision-making, evaluation, implementation, their organizational management is considered. Planning is very important in management. This importance arises from the fact that effective planning affects the behavior of management and the organization in practice and deeply, and enables effective control of organizational activities. In order to be organized in the school, the principal must identify the activities necessary to achieve the goals and implement the programs, as well as group the activities according to material and human resources. And in coordination to create unity and unity between the activities of different units of the organization so that the goals of the organization are effectively achieved. Every purposeful collective activity requires supervision and control, the realities of organizational life require precise control of their activities. Organizations are subject to constant change and therefore their activities are becoming more complex day by day, the employees of the organization are human beings and their behavior is not free from error and mistake, and delegating authority to facilitate the work is inevitable. All of this points to the supervision and control of school principals and highlights its importance. Decision making as one of the important functions of management is at the forefront of all tasks and is present and influential in all other functions without exception. If we think that decision-making means choosing one of the various ways to solve a problem, we can not do any planning, organizing, monitoring and controlling without making a decision. No management and organization can achieve its ideals and goals without reviewing the results of its work and performance. Evaluation is one of the basic tasks of management that measures the achievement of goals by reviewing and researching the performance of individuals and the organization and provides the grounds for removing obstacles, modifying methods, improving forces and finally going through other stages of movement and growth in the organization. Once all the processes of management functions, including planning, organizing, coordinating, and decision-making, have been identified, it is time to implement and implement these decisions. Implement the rules of the country's education system properly in schools.
Resource Management: Resource management means the management of human and financial affairs and material affairs. In human affairs, the principal deals with the administrative affairs of the students and school staff, and in financial affairs, he spends the school budget, allocates resources, saves expenses, etc., and in material affairs, he takes care of the school building and property. In the humanities, the principal is responsible for the admission, registration, grouping of students and maintenance of various statistics such as personal and academic records and information, as well as identifying the abilities and needs of students and teachers and their upbringing, as well as recruitment, employment, training and employment. Pays for their maintenance and so on. In the present study, the principal's finances mean the success rate of the principal in budgeting, resource allocation, cost savings, etc. in the school. And the purpose of material or physical affairs is to provide the necessary information in the field of educational materials and facilities, facilities, classroom equipment and forecasting future needs and facilities, etc.
Communication Management: Communication management means the set of communication skills of managers' cooperation and partnership with teachers, parents and success in communicating effectively with students and communicating with outside communities.
Professional management: Professional management means the ability of the principal in creativity and solving problems and problems of the school and providing appropriate solutions, receptive and demanding change and innovation in the school. Problem Solving In art management, finding ways to get from where you are to where you want to go is defined, although it is assumed that the manager does not already know how to get there. Creativity is one of the basic aspects in expanding the capabilities of knowledgeable human resources. Change in educational institutions always happens and creates opportunities for positive growth. In order for educational administrators to become real leaders, they must consider change and innovation as positive challenges for the improvement of their country's schools and educational districts, so according to this concept, one of the basic roles and responsibilities of administrators is change and innovation within the organization. In the technology component, a school principal must be able to apply new methods of information technology in performing professional and organizational tasks.
Ethical management: Ethical management means a set of behavioral characteristics that lead to the observance of the common rights of colleagues and stakeholders and is manifested in issues such as justice and fairness, judgment, accountability and responsibility, etc. Fairness from the root half means equal distribution of resources, but justice from the root of justice seeks to allocate resources in an efficient, effective and principled manner and with maximum satisfaction for the parties. In this regard, a fair manager seeks to halve everything among his employees, while a fair manager seeks to find a way to best allocate resources between the proportion of efficiency and performance with the availability of resources. Now these resources can be financial resources, such as salaries, wages, or based on material and non-material rewards, the amount of attention paid to staff or training facilities. Accountability is a commitment to responsibility and is one of the basic and important characteristics of managers. Responsibility is a sense of duty and commitment on the part of management to meet the needs or interests of stakeholders. In other words, the performance of the entrusted tasks is well defined by the management in order to maintain and promote the welfare of the stakeholders and the goals of the organization. The term accountability refers to the concept of "answering". In other words, accountability is defined as taking on the results and consequences of actions and actions, if the needs and interests are not met, as well as measures to improve the situation.
The rate of academic achievement and growth of students: In any education system, one of the important indicators for evaluating the performance of schools is the rate of academic achievement of students. In schools, the performance of school principals directly affects the performance of teachers and indirectly affects the academic achievement of students. Therefore, in any education system, one of the important indicators for evaluating the performance of schools is the academic achievement of students.
Client Satisfaction: Satisfaction is a positive feeling that is created in stakeholders after receiving services, and this will happen if the principal at the school meets the expectations of his clients.
The results showed that paying attention to the identified dimensions can help senior principals in accurately and comprehensively diagnosing the performance of school principals, and provide the basis for optimal decision-making, selection and correct selection.- انتشار مقاله: 09-05-1399
- نویسندگان: Fereshteh Ghaemi,Seyed Mohammad Mirkamali,Reza Rostami,Keyvan Salehi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of School Administration
- نوع مقاله: Journal Article
- کلمات کلیدی: Performance,appraisal,evaluating the performance,evaluating
- چکیده: با توجه به نقش برجستۀ رهبری و مدیریت در عرصۀ دستیابی به اهدف سازمانها، به ویژه مدیران مدارس در نظام آموزش و پرورش، توجه به عملکرد آنان و ارزیابی این عملکردها اهمیت بسیاری دارد. از این رو پژوهش حاضر با هدف ارائۀ مدل مفهومی برای ارزیابی عملکرد مدیران مدارس انجام شد. روش پژوهش کیفی و از نوع فراترکیب بود. گردآوری دادهها به روش اسنادی و با بررسی تمامی منابع علمی مرتبط با موضوع ارزیابی عملکرد مدیران مدارس (1380-1398داخلی و 19990-2019 خارجی) انجام شد. بدین منظور، کلیدواژههای مربوط به دو دهۀ اخیر، از جمله: ارزشیابی و ارزیابی عملکرد مدیران، وظایف مدیران، استانداردهای عملکردی مدیران، ویژگیهای و شایستگیهای مدیران و صلاحیتهای حرفهای مدیران (مدارس) در پایگاههای داخلی نظیر پایگاه اطلاعات علمی؛ اس آی دی، و پایگاه دادههای خارجی همچون گوگل اسکولار، اسکوپوس، امرالد، الزویر، پروکوئست اشپینگر تیلور و فرانسیس بررسی شد. با بررسی کامل 47 منبع از 1123 منبع اولیه، 8 مؤلفۀ اصلی و 28 زیرمؤلفه به عنوان ملاکهای ارزیابی عملکرد مدیران مدارس، شناسایی و طبقهبندی شد. نتایج حاصل از این بررسی نشان داد که توجه به ابعاد شناسایی شده، میتواند به مدیران ارشد در تشخیص دقیق و همهجانبۀ عملکرد مدیران مدارس، کمک کند و زمینۀ تصمیمگیری بهینه، گزینش و انتخاب صحیح آنها را فراهم کند.
- چکیده انگلیسی:
Considering the prominent role of principals in achieving the goals of organizations, especially school principals, it is very important to pay attention to and evaluate their performance. Therefore, the present study aims to provide a conceptual model for evaluating the performance of school principals. The research method is qualitative and meta-combined. Data collection was done by documentary method and by reviewing all scientific sources related to the subject of evaluating the performance of school principals (domestic 1380-1398 and foreign 1990-2011). To this end, in the last two decades, the keywords of evaluating and evaluating the performance of principals, duties of principals, performance standards of principals, characteristics and competencies of principals and professional competencies of principals (schools) in internal databases such as scientific database; SIDs, and external databases such as Google Scholar, Scopus, Emerald, Elsevier, Proquest Spinger Taylor, and Francis were examined with a complete review of 47 sources from 1123 primary sources, 8 main components, and 28 subcomponents as criteria for evaluating school principals' performance. , Identified and classified. It is noteworthy that the findings of this study as a model after going through seven steps of meta-combination and screening of backgrounds and resources obtained, finally by examining 47 sources, the components of school principals' performance evaluation were obtained. Also, after analyzing the components into 28 components and 8 dimensions, which include "Educational Leadership", "Organizational Management", "Resource Management", "Communication Management", "Professional Management", "Ethical Management", "Students' Academic Achievement" And "Client Satisfaction" were categorized.
Educational Leadership < /em>: Educational leadership is an effective process of guiding the talents and energy of teachers, students and parents in achieving common educational goals, whose role is to support, strengthen and help, and ultimately cooperate with members of the organization to improve and develop education in schools. In this study, educational leadership refers to a set of core responsibilities of school principals, namely guidance and leadership, teaching learning, vision definition, professional development, motivation, support, cultural education and improving the school climate.
In the role of leadership, school principals direct the activities of staff or teachers and students in order to achieve the goals of the organization, and also teach and teach them, which is the most important task of school principals, to develop students and to develop the professional profession of teachers. . In order to achieve the goals of the organization, it draws a common vision that is clear to all members of the organization and creates a common understanding of it for teachers, staff and parents. In the motivating role, it recognizes and understands the needs, behavior and personality of students, teachers and staff and guides the behavior towards the desired behavior based on feelings of respect, value, positive self-concept, cognition, self-awareness, justice and understanding the talents and strengths of individuals. Also, in the role of support, it should be the source of solving the problem and opening the work knot of teachers, staff and students. In this sense, the principal is responsible for providing the necessary information, favorable contexts and opportunities to solve the problems of teachers and students, and in the role of educational and cultural affairs, the director cooperates with extracurricular activities that are outside the official programs related to educational and cultural issues. The principal works with a foster care teacher in the school with the aim of protecting the boundaries of belief and preserving the achievements and explaining the values of the country, as well as the development of students' social skills. The school atmosphere is a relatively stable quality of the school environment that is created through the relationship between principal and teachers, teachers and teachers, teachers and staff, teachers and students, or relationships between students, and is based on a collective perception of school behavior. Other schools are distinguished in terms of the effect that the school atmosphere has on the success and performance of the school should be given serious attention by school principals, and the principal in this role should seek to create a joker and effort and intimacy and camaraderie in the school.
Organizational management: Organizational management refers to the general duties of principals in schools. In this model, the set of functions of managers, namely planning, organizing, coordinating, monitoring and controlling, decision-making, evaluation, implementation, their organizational management is considered. Planning is very important in management. This importance arises from the fact that effective planning affects the behavior of management and the organization in practice and deeply, and enables effective control of organizational activities. In order to be organized in the school, the principal must identify the activities necessary to achieve the goals and implement the programs, as well as group the activities according to material and human resources. And in coordination to create unity and unity between the activities of different units of the organization so that the goals of the organization are effectively achieved. Every purposeful collective activity requires supervision and control, the realities of organizational life require precise control of their activities. Organizations are subject to constant change and therefore their activities are becoming more complex day by day, the employees of the organization are human beings and their behavior is not free from error and mistake, and delegating authority to facilitate the work is inevitable. All of this points to the supervision and control of school principals and highlights its importance. Decision making as one of the important functions of management is at the forefront of all tasks and is present and influential in all other functions without exception. If we think that decision-making means choosing one of the various ways to solve a problem, we can not do any planning, organizing, monitoring and controlling without making a decision. No management and organization can achieve its ideals and goals without reviewing the results of its work and performance. Evaluation is one of the basic tasks of management that measures the achievement of goals by reviewing and researching the performance of individuals and the organization and provides the grounds for removing obstacles, modifying methods, improving forces and finally going through other stages of movement and growth in the organization. Once all the processes of management functions, including planning, organizing, coordinating, and decision-making, have been identified, it is time to implement and implement these decisions. Implement the rules of the country's education system properly in schools.
Resource Management: Resource management means the management of human and financial affairs and material affairs. In human affairs, the principal deals with the administrative affairs of the students and school staff, and in financial affairs, he spends the school budget, allocates resources, saves expenses, etc., and in material affairs, he takes care of the school building and property. In the humanities, the principal is responsible for the admission, registration, grouping of students and maintenance of various statistics such as personal and academic records and information, as well as identifying the abilities and needs of students and teachers and their upbringing, as well as recruitment, employment, training and employment. Pays for their maintenance and so on. In the present study, the principal's finances mean the success rate of the principal in budgeting, resource allocation, cost savings, etc. in the school. And the purpose of material or physical affairs is to provide the necessary information in the field of educational materials and facilities, facilities, classroom equipment and forecasting future needs and facilities, etc.
Communication Management: Communication management means the set of communication skills of managers' cooperation and partnership with teachers, parents and success in communicating effectively with students and communicating with outside communities.
Professional management: Professional management means the ability of the principal in creativity and solving problems and problems of the school and providing appropriate solutions, receptive and demanding change and innovation in the school. Problem Solving In art management, finding ways to get from where you are to where you want to go is defined, although it is assumed that the manager does not already know how to get there. Creativity is one of the basic aspects in expanding the capabilities of knowledgeable human resources. Change in educational institutions always happens and creates opportunities for positive growth. In order for educational administrators to become real leaders, they must consider change and innovation as positive challenges for the improvement of their country's schools and educational districts, so according to this concept, one of the basic roles and responsibilities of administrators is change and innovation within the organization. In the technology component, a school principal must be able to apply new methods of information technology in performing professional and organizational tasks.
Ethical management: Ethical management means a set of behavioral characteristics that lead to the observance of the common rights of colleagues and stakeholders and is manifested in issues such as justice and fairness, judgment, accountability and responsibility, etc. Fairness from the root half means equal distribution of resources, but justice from the root of justice seeks to allocate resources in an efficient, effective and principled manner and with maximum satisfaction for the parties. In this regard, a fair manager seeks to halve everything among his employees, while a fair manager seeks to find a way to best allocate resources between the proportion of efficiency and performance with the availability of resources. Now these resources can be financial resources, such as salaries, wages, or based on material and non-material rewards, the amount of attention paid to staff or training facilities. Accountability is a commitment to responsibility and is one of the basic and important characteristics of managers. Responsibility is a sense of duty and commitment on the part of management to meet the needs or interests of stakeholders. In other words, the performance of the entrusted tasks is well defined by the management in order to maintain and promote the welfare of the stakeholders and the goals of the organization. The term accountability refers to the concept of "answering". In other words, accountability is defined as taking on the results and consequences of actions and actions, if the needs and interests are not met, as well as measures to improve the situation.
The rate of academic achievement and growth of students: In any education system, one of the important indicators for evaluating the performance of schools is the rate of academic achievement of students. In schools, the performance of school principals directly affects the performance of teachers and indirectly affects the academic achievement of students. Therefore, in any education system, one of the important indicators for evaluating the performance of schools is the academic achievement of students.
Client Satisfaction: Satisfaction is a positive feeling that is created in stakeholders after receiving services, and this will happen if the principal at the school meets the expectations of his clients.
The results showed that paying attention to the identified dimensions can help senior principals in accurately and comprehensively diagnosing the performance of school principals, and provide the basis for optimal decision-making, selection and correct selection.- انتشار مقاله: 09-05-1399
- نویسندگان: Fereshteh Ghaemi,Seyed Mohammad Mirkamali,Reza Rostami,Keyvan Salehi
- مشاهده
- جایگاه : پژوهشی
- مجله: Pure Life
- نوع مقاله: Journal Article
- کلمات کلیدی: Cyberspace,Religious teachings,Media Management,Practical Solutions
- چکیده: در دنیای امروز که رسانه های ارتباط جمعی به شکل های مختلفی زندگی انسان را احاطه کرده و افکار او را جهت دهی می کنند، فضای جدیدی در مباحث مربوط به دین و ارتباط آن با رسانه به وجود آمده است که از یک طرف راه را برای تبلیغ معارف دینی و بالا بردن سطح آموزش های دینی هموارتر نموده و حرکت به سوی برنامه های نوین تبلیغی را نوید می دهد؛ اما از سوی دیگر، بستر فراگیری را در اختیار دشمنان دین و شبهه افکنان قرار می دهد.
در این میان و برای اینکه رسانه های مختلف- به ویژه اینترنت- بتوانند توان بالایی در این عرصه داشته باشند؛ نیاز به مدیریتی کارآمد در این عرصه خودنمایی می کند.
مدیریت رسانه بر دو پایه اساسی مدیریت مطلوب سازمان رسانه ای و مدیریت محتوای رسانه ای استوار است؛ فضای مجازی نیز به عنوان یک رسانه بسیار گسترده و در دسترس ظرفیت بالایی در تبلیغ و آموزش معارف دینی دارد، که برای تحقق هر چه بیشتر چنین ظرفیتی نیاز به راهکارهای عملی در بخش مدیریت رسانه است.
برای تولید یک بسته تبلیغی یا آموزشی و ارائه و کسب موفقیت در ارائه آن که جلب اعتماد مخاطب و تأثیرگذاری در افکار اوست، عوامل متعددی دخیل هستند؛ از جمله افراد، ابزارها و روشها که با هماهنگی و پویایی بیشتر هر کدام از این بخش ها می توان به یک رسانه جذاب، پرمخاطب و تأثیرگذار رسید.
بنابراین، بسته تهیه شده برای تبلیغ یا آموزش در فضای مجازی باید جذاب باشد؛ برای جذاب شدن آن نیز لازم است به مؤلفه هایی همچون نیاز مخاطب و سرگرمی و چگونگی طراحی توجه کرد؛ همچنین این بسته باید در تمام ابزارهای معمول دریافت کننده اینترنت قابل دسترسی باشد.
در این پژوهش سعی شده با استفاده از اصول مدیریت رسانه و چشم پوشی از برخی مباحث تئوری، راهکارهای عملی برای رسیدن به یک رسانه جذاب، پرمخاطب و تأثیرگذار ارائه شود.- چکیده انگلیسی: In today's world where the mass media surrounds human life in various ways and directs his thoughts, a new space has emerged in the discussion of religion and its relationship with the media, which on the one hand paves the way for propaganda. Religious education and raising the level of religious education will make it smoother and promise to move towards new propaganda programs; But on the other hand, it provides a pervasive platform for the enemies of religion and skeptics.
In the meantime, and so that various media - especially the Internet - can have high power in this area; The need for efficient management in this area is evident.
Media management is based on two basic foundations: optimal management of the media organization and media content management; Cyberspace, as a very wide and accessible medium, has a high capacity in propagating and teaching religious teachings, which requires practical solutions in the field of media management to realize such a capacity as much as possible.
There are several factors involved in producing a promotional or educational package and presenting and succeeding in presenting it, which is to gain the audience's trust and influence in his thoughts; Including people, tools and methods that with more coordination and dynamism of each of these sections can be achieved an attractive, popular and effective medium.
Therefore, the package prepared for advertising or training in cyberspace should be attractive; To make it attractive, it is necessary to pay attention to components such as the needs of the audience and entertainment and how to design; This package should also be available on all common Internet receiving devices.
In this research, using the principles of media management and ignoring some theoretical issues, practical solutions to achieve an attractive, popular and effective media are presented.- انتشار مقاله: 15-05-1396
- نویسندگان: Reza Rostami,Reza Rostami,Reza Rostami
- مشاهده
- جایگاه : پژوهشی
- مجله: Polyolefins Journal
- نوع مقاله: Journal Article
- کلمات کلیدی: Microstructure,Oil,Olefin,oligomerization,metallocene
- چکیده:
- چکیده انگلیسی: Herein a quenched-flow kinetic technique was applied to calculate the rate constants of 1-hexene and 1-octene oligomerization catalyzed by the Cp2ZrCl2 and Cp2HfCl2/MAO catalyst systems, and subsequently a mechanism for the higher α-olefin oligomerization reaction was proposed. The oligomerization results showed that Zr-based catalyst in the oligomerization of 1-octene had the highest activity of 17 in comparison to Hfbased one with an activity value of 15 g oligomer/(mmolCat.h)). According to the obtained results, increasing monomer length led to a shift in molecular weight and polydispersity index value (Mw/Mn) to lower values. Furthermore, the microstructure-viscosity relationship was followed by the calculation of branching ratio and short-chain branching percentage. The obtained results revealed that, the oligomers synthesized by the Cp2HfCl2 catalyst had lower short chain branching ratio value and short-chain branching percentages. According to the kinetic results, the initiation rate constant (ki) of Zr-based catalyst was higher than that of Hf-based catalyst, and the order of calculated propagation rate constants was Zr>Hf for both the 1-hexene and 1-octene-based oligomerizations.
- انتشار مقاله: 14-08-1399
- نویسندگان: Ahad Hanifpour,Mahdi Hashemzadeh Gargari,Mohammad Reza Rostami Darounkola,Zahra Kalantari,Naeimeh Bahri-Laleh
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Diazinon,Rana ridibunda,Liver tissue,hepatic enzymes
- چکیده:
- چکیده انگلیسی: The purpose of this study was to examine the acute and sub-acute effects of diazinon on
histopathological parameters of liver tissue and blood level of hepatic enzymes of male common
frog (Rana ridibunda). Frogs were assigned to 9 groups (n=8, meaning 8 frogs in each group):
control and treatment groups with 30, 60, 90 and 120 μg/L diazinon in water for one day or one
week. Hepatic enzymes containing alanine transaminase (ALT), aspartate aminotransferase
(AST), and alkaline phosphatase (ALP) were measured using biochemical kit. All ALP values
were significantly different between the control group and one-day and one-week diazinon
exposed groups. Hepatocyte changes were observed only for diazinon concentrations greater
than 60 μl after one week. The most important characteristics of the affected cells were
hyperplasia and chromatin formation. Results show that sub-lethal concentrations of diazinon
have an increasing effect on the blood level of hepatic enzymes, which probably indicated the
detoxification response of liver on the basis of diazinon sub-lethal effect model.- انتشار مقاله: 17-11-1392
- نویسندگان: Leila Ghasemzadeh,Hamidreza Mohajereani,Sima Nasri,Alireza Rostami
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Diazinon,Rana ridibunda,Liver tissue,hepatic enzymes
- چکیده:
- چکیده انگلیسی: The purpose of this study was to examine the acute and sub-acute effects of diazinon on
histopathological parameters of liver tissue and blood level of hepatic enzymes of male common
frog (Rana ridibunda). Frogs were assigned to 9 groups (n=8, meaning 8 frogs in each group):
control and treatment groups with 30, 60, 90 and 120 μg/L diazinon in water for one day or one
week. Hepatic enzymes containing alanine transaminase (ALT), aspartate aminotransferase
(AST), and alkaline phosphatase (ALP) were measured using biochemical kit. All ALP values
were significantly different between the control group and one-day and one-week diazinon
exposed groups. Hepatocyte changes were observed only for diazinon concentrations greater
than 60 μl after one week. The most important characteristics of the affected cells were
hyperplasia and chromatin formation. Results show that sub-lethal concentrations of diazinon
have an increasing effect on the blood level of hepatic enzymes, which probably indicated the
detoxification response of liver on the basis of diazinon sub-lethal effect model.- انتشار مقاله: 17-11-1392
- نویسندگان: Leila Ghasemzadeh,Hamidreza Mohajereani,Sima Nasri,Alireza Rostami
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Diazinon,Rana ridibunda,Liver tissue,hepatic enzymes
- چکیده:
- چکیده انگلیسی: The purpose of this study was to examine the acute and sub-acute effects of diazinon on
histopathological parameters of liver tissue and blood level of hepatic enzymes of male common
frog (Rana ridibunda). Frogs were assigned to 9 groups (n=8, meaning 8 frogs in each group):
control and treatment groups with 30, 60, 90 and 120 μg/L diazinon in water for one day or one
week. Hepatic enzymes containing alanine transaminase (ALT), aspartate aminotransferase
(AST), and alkaline phosphatase (ALP) were measured using biochemical kit. All ALP values
were significantly different between the control group and one-day and one-week diazinon
exposed groups. Hepatocyte changes were observed only for diazinon concentrations greater
than 60 μl after one week. The most important characteristics of the affected cells were
hyperplasia and chromatin formation. Results show that sub-lethal concentrations of diazinon
have an increasing effect on the blood level of hepatic enzymes, which probably indicated the
detoxification response of liver on the basis of diazinon sub-lethal effect model.- انتشار مقاله: 17-11-1392
- نویسندگان: Leila Ghasemzadeh,Hamidreza Mohajereani,Sima Nasri,Alireza Rostami
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Diazinon,Rana ridibunda,Liver tissue,hepatic enzymes
- چکیده:
- چکیده انگلیسی: The purpose of this study was to examine the acute and sub-acute effects of diazinon on
histopathological parameters of liver tissue and blood level of hepatic enzymes of male common
frog (Rana ridibunda). Frogs were assigned to 9 groups (n=8, meaning 8 frogs in each group):
control and treatment groups with 30, 60, 90 and 120 μg/L diazinon in water for one day or one
week. Hepatic enzymes containing alanine transaminase (ALT), aspartate aminotransferase
(AST), and alkaline phosphatase (ALP) were measured using biochemical kit. All ALP values
were significantly different between the control group and one-day and one-week diazinon
exposed groups. Hepatocyte changes were observed only for diazinon concentrations greater
than 60 μl after one week. The most important characteristics of the affected cells were
hyperplasia and chromatin formation. Results show that sub-lethal concentrations of diazinon
have an increasing effect on the blood level of hepatic enzymes, which probably indicated the
detoxification response of liver on the basis of diazinon sub-lethal effect model.- انتشار مقاله: 17-11-1392
- نویسندگان: Leila Ghasemzadeh,Hamidreza Mohajereani,Sima Nasri,Alireza Rostami
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Oral Health and Oral Epidemiology
- نوع مقاله: Journal Article
- کلمات کلیدی: Behavior control,Pediatric Dentistry,Parental Consent
- چکیده:
- چکیده انگلیسی: BACKGROUND AND AIM: Parents’ attitudes towards different aspects of dentistry especially the use of behavior management techniques (BMTs) can greatly effect a child’s cooperation in a dental office. The present quasi-experimental study was conducted with the aim to assess the effect of a verbal explanation on parents’ acceptance level of the most common BMTs used in pediatric dentistry.METHODS: A videotaped presentation showing the 6 most commonly used BMTs in Iran was presented to 60 parents recruited by a convenient sampling method. Using visual analogue scale (VAS), the acceptance level of each BMT was measured before and after an explanation on the reasons of each BMT. Paired t-test, repeated measures analysis of variance (ANOVA) and independent t-test were used for statistical analysis of data. Significance level was set as 0.050.RESULTS: Giving a verbal explanation on BMTs had a statistically significant effect on the acceptance of BMTs. Tell-show-do (TSD) and hand-over-mouth (HOM) techniques achieved the highest and lowest mean scores of parental acceptance, respectively. The acceptance of physical restraint (P = 0.013) and parental presence/absence (PPA) (P = 0.015) of parents was obtained higher among men compared to women using t-test.CONCLUSION: Giving an explanation to parents while performing a BMT is effective in raising parents' acceptance of the technique. Non-invasive methods such as TSD and PPA of parents are the more favorable methods to parents.
- انتشار مقاله: 07-01-1397
- نویسندگان: Fatemeh Jahanimoghadam,Naimeh Hasheminejad,Azadeh Horri,Mohammad Reza Rostamizadeh,Mohammad Reza Baneshi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Health Sciences and Surveillance System
- نوع مقاله: Journal Article
- کلمات کلیدی: Cortisol,Blood,Industry,noise,Steel
- چکیده:
- چکیده انگلیسی: Background: Noise is one of the most important hazardous physical factors in industrial environments. This study aimed to determine the effects of noise exposure on serum cortisol level and some blood parameters among male workers of a steel production company.Methods: This cross-sectional study was conducted on 50 male workers in a steel production company. In order to assess the changes in blood parameters, such as serum cortisol level, lipid profile, and blood sugar, blood samples were taken from the participants before and after the work shift. Besides, CEL 440 sound level meter was used to measure the equivalent sound pressure level (LAeq) and analyze the noise in octave band frequencies. Analyses of data were performed by SPSS software (version 16) using the Paired sample t-test.Results: The laboratory findings indicated an increase in serum cortisol at all exposure levels. However, the changes were not statistically significant. An increase was observed in blood sugar levels at all the three noise levels and the increment was statistically significant at 95 dB noise level.Conclusion: The present study showed that exposure to high sound levels leads to changes in biological parameters, although under the scenario explained in this study these changes did not reach statistical significant.
- انتشار مقاله: 13-11-1393
- نویسندگان: Zahra Zamanian,Reza Rostami,Kiana Nikeghbal
- مشاهده