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111.
Ali Khosrowbeygi Nosratollah Zarghami 《Indian journal of clinical biochemistry : IJCB》2008,23(1):49-52
There is growing evidence that damage to spermatozoa by reactive oxygen species play a key role in male infertility. The aim
of this study was to assess seminal plasma free 8-Isoprostane levels in men with asthenozoospermia, asthenoteratozoospermia
and oligoasthenoteratozoospermia compared to normozoospermic males and its correlation with seminal parameters. The case group
consisted of men with asthenozoospermia (n=15), asthenoteratozoospermia (n=16) and oligoasthenoteratozoospermia (n=15). The
control group consisted of 16 males with normozoospermia. After Purification of Free 8-Isoprostane by affinity column, its
concentration was measured by enzyme immunoassay method. Free 8-Isoprostane evaluation showed significantly greater values
in the total case group (n=46) versus control group (18.23±3.56 vs 2.6±0.38 ng/ml). In each case group free 8-Isoprostane
also showed a significant increasing compared to normozoospermic males. Free 8-Isoprostane showed an inversely significant
correlation with sperm motility and sperm morphology. Lipid peroxidation could have significant role in etiology of sperm
abnormalities. Measurement of 8-Isoprostane can be used as a specific biomarker for assessing lipid peoxidation in sperm. 相似文献
112.
Simsek Hasan Yildirim Ali 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2000,46(3-4):327-342
The data used in this paper were derived from a larger project which had the aim of critically evaluating the Turkish vocational education system on a number of different levels. This article examines the administrative and organisational practices in a selected group of secondary vocational schools in Turkey from the point of view of school administrators, teachers and industrial managers. The results indicate that the Turkish vocational education system is characterised by a centralised, top-down bureaucracy, which inhibits innovative capacity. The authors argue that a degree of decentralisation is necessary at various levels of the system. 相似文献
113.
Mahdi Dehghan Maryam Biabani Ahmad Ali Abin 《Information processing & management》2019,56(3):1067-1079
Cost optimization continues to be a critical concern for many human resources departments. The key is to balance between costs and business value. In particular, computer science organizations prefer to hire people who are expert in only one skill area and have a slight superficial knowledge in other areas that gives them the ability to collaborate across different aspects of project. Community Question Answering networks provide good platforms for people and organizations to share knowledge and find experts. An important issue in expert finding is that an expert has to constantly update his knowledge after being saturated in his field of expertise to still be identified as expert. A person who fails to preserve his expertise is likely to lose his expertise. This work justifies this question that does take the concept of time into account improve the quality of expertise retrieval. We propose a new method for T-shaped expert finding that is based on temporal expert profiling. The proposed method takes the temporal property of expertise into account to mine the shape of expertise for each candidate expert based on his profile. To this end, for each candidate expert, we take snapshots of his expertise trees at regular time intervals and learn the relation between temporal changes in different expertise trees and candidates’ profile. Finally, we use a filtering technique that is applied on top of the profiling method, to find shape of expertise for candidate experts. Experimental results on a large test collection show the superiority of the proposed method in terms of quality of results in comparison with state-of-the-art. 相似文献
114.
Seyed Amin Mirlohi Falavarjani Fattane Zarrinkalam Jelena Jovanovic Ebrahim Bagheri Ali A. Ghorbani 《Information processing & management》2019,56(6):102070
The ever increasing presence of online social networks in users’ daily lives has led to the interplay between users’ online and offline activities. There have already been several works that have studied the impact of users’ online activities on their offline behavior, e.g., the impact of interaction with friends on an exercise social network on the number of daily steps. In this paper, we consider the inverse to what has already been studied and report on our extensive study that explores the potential causal effects of users’ offline activities on their online social behavior. The objective of our work is to understand whether the activities that users are involved with in their real daily life, which place them within or away from social situations, have any direct causal impact on their behavior in online social networks. Our work is motivated by the theory of normative social influence, which argues that individuals may show behaviors or express opinions that conform to those of the community for the sake of being accepted or from fear of rejection or isolation. We have collected data from two online social networks, namely Twitter and Foursquare, and systematically aligned user content on both social networks. On this basis, we have performed a natural experiment that took the form of an interrupted time series with a comparison group design to study whether users’ socially situated offline activities exhibited through their Foursquare check-ins impact their online behavior captured through the content they share on Twitter. Our main findings can be summarised as follows (1) a change in users’ offline behavior that affects the level of users’ exposure to social situations, e.g., starting to go to the gym or discontinuing frequenting bars, can have a causal impact on users’ online topical interests and sentiment; and (2) the causal relations between users’ socially situated offline activities and their online social behavior can be used to build effective predictive models of users’ online topical interests and sentiments. 相似文献
115.
Zenun Kastrati Ali Shariq Imran Sule Yildirim Yayilgan 《Information processing & management》2019,56(5):1618-1632
This paper presents a semantically rich document representation model for automatically classifying financial documents into predefined categories utilizing deep learning. The model architecture consists of two main modules including document representation and document classification. In the first module, a document is enriched with semantics using background knowledge provided by an ontology and through the acquisition of its relevant terminology. Acquisition of terminology integrated to the ontology extends the capabilities of semantically rich document representations with an in depth-coverage of concepts, thereby capturing the whole conceptualization involved in documents. Semantically rich representations obtained from the first module will serve as input to the document classification module which aims at finding the most appropriate category for that document through deep learning. Three different deep learning networks each belonging to a different category of machine learning techniques for ontological document classification using a real-life ontology are used.Multiple simulations are carried out with various deep neural networks configurations, and our findings reveal that a three hidden layer feedforward network with 1024 neurons obtain the highest document classification performance on the INFUSE dataset. The performance in terms of F1 score is further increased by almost five percentage points to 78.10% for the same network configuration when the relevant terminology integrated to the ontology is applied to enrich document representation. Furthermore, we conducted a comparative performance evaluation using various state-of-the-art document representation approaches and classification techniques including shallow and conventional machine learning classifiers. 相似文献
116.
The literature has identified barriers with library staff as one of the important barriers affecting academic activities of students and also recognized the relationship of various academic and demographic characteristics of students with it. The emotions management skills of students may be one of the possible correlates of the barriers with library staff. This study was designed to investigate the levels of barriers with library staff and emotions management skills as well as their possible correlation using two standardized scales. The data were collected from the final year undergraduate agriculture students. The results confirmed the existence of barriers with library staff among the participants of both genders experiencing the same level of anxiety. The participants scored 3.75 (average) on the emotions management scale. The results also revealed significantly negative correlation between emotions management skills and barriers with library staff among these students. These results have many practical implications in the sphere of academic librarianship. 相似文献
117.
Sharon Farnel Ali Shiri Sandra Campbell Cathy Cockney Dinesh Rathi Robyn Stobbs 《Cataloging & classification quarterly》2017,55(5):289-306
This article describes the Digital Library North (DLN) project, a collaboration among researchers at the University of Alberta, staff at the Inuvialuit Cultural Resource Centre, and communities within the Inuvialuit Settlement Region (ISR) to develop a culturally appropriate metadata framework for a digital library of cultural resources. It will discuss gathering of data to inform the first iteration of the metadata framework and digital library prototype, as well as revisions made to both the framework and the digital library based on feedback obtained through community interaction with the prototype. 相似文献
118.
Iranian librarianship is developing rapidly. While there have been libraries in Iran for several millenia, it is only in the last two or three years that libraries have begun to move forward in modern fashion. Perhaps now that they are improving, an assessment of their status is appropriate, so this paper will attempt to describe the current pattern of Iranian library service and the directions it is likely to take. 相似文献
119.
Ait Si Mhamed Ali 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2019,65(5):833-837
International Review of Education - 相似文献
120.