79 research outputs found

    A review of the molecular epidemiology of Cryptosporidium spp. and Giardia duodenalis in the Middle East and North Africa (MENA) region

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    Cryptosporidium spp. and Giardia duodenalis are important protozoan parasites which are associated with diarrheal diseases in humans and animals worldwide. Relatively little is known about the molecular epidemiology of Cryptosporidium spp. and Giardia duodenalis in the Middle East Countries and North Africa (MENA region). Therefore, this review aimed to inspect published genotyping and subtyping studies on Cryptosporidium spp. and Giardia duodenalis in the MENA region. These studies indicate that both anthroponotic and zoonotic transmission of Cryptosporidium occurs with the predominance of zoonotic transmission in most countries. Seven Cryptosporidium species were identified in humans (C. parvum, C. hominis, Cryptosporidium meleagridis, C. felis, Cryptosporidium muris, C. canis and C. bovis), with C. parvum by far being the most prevalent species (reported in 95.4% of the retrieved studies). Among C. parvum gp60 subtype families, IIa and IId predominated, suggesting potential zoonotic transmission. However, in four MENA countries (Lebanon, Israel, Egypt and Tunisia), C. hominis was the predominant species with five subtype families reported including Ia, Ib, Id, If and Ie, all of which are usually anthroponotically transmitted between humans. In animals, the majority of studies were conducted mainly on livestock and poultry, 15 species were identified (C. parvum, C. hominis, C. muris, Cryptosporidium cuniculus, C. andersoni, C. bovis, C. meleagridis, C. baileyi, C. erinacei, C. ryanae, C. felis, C. suis, Cryptosporidium galli, C. xiaoi and C. ubiquitum) with C. parvum (IIa and IId subtypes) the dominant species in livestock and C. meleagridis and C. baileyi the dominant species in poultry. With G. duodenalis, five assemblages (A, B, C, E and F) were identified in humans and six (A, B, C, E, D and F) in animals in MENA countries with assemblages A and B commonly reported in humans, and assemblages A and E dominant in livestock. This review also identified a major knowledge gap in the lack of Cryptosporidium spp. and Giardia duodenalis typing studies in water and food sources in the MENA region. Of the few studies conducted on water sources (including drinking and tap water), ten Cryptosporidium species and four genotypes were identified, highlighting the potential role of water as the major route of Cryptosporidium spp. transmission in the region. In addition, three G. duodenalis assemblages (A, B and E) were detected in different water sources with AI, AII and BIV being the main sub-assemblages reported. More research is required in order to better understand the molecular diversity and transmission dynamics of Cryptsporidum spp. and Giardia duodenalis in humans, animals, water and food sources in MENA region

    A General Evaluation Framework for Text Based Conversational Agent

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    This paper details the development of a new evaluation framework for a text based Conversational Agent (CA). A CA is an intelligent system that handle spoken or/and text based conversations between machine and human. Generally, the lack of evaluation frameworks for CAs effects its development. The idea behind any system’s evaluation is to make sure about the system’s functionalities and to continue development on it. A specific CA has been chosen to test the proposed framework on it; namely ArabChat. The ArabChat is a rule based CA and uses pattern matching technique to handle user’s Arabic text based conversations. The proposed and developed evaluation framework in this paper is natural language independent. The proposed framework is based on the exchange of specific information between ArabChat and user called “Information Requirements”. This information are tagged for each rule in the applied domain and should be exist in a user’s utterance (conversation). A real experiment has been done in Applied Science University in Jordan as an information point advisor for their native Arabic students to evaluate the ArabChat and then evaluating the proposed evaluation framework

    The Enhanced Arabchat: An Arabic Conversational Agent

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    The Enhanced ArabChat is a complement of the previous version of ArabChat. This paper details an enhancements development of a novel and practical Conversational Agent for the Arabic language called the “Enhanced ArabChat”. A conversational Agent is a computer program that attempts to simulate conversations between machine and human. Some of lessons was learned by evaluating the previous work of ArabChat . These lessons revealed that two major issues affected the ArabChat’s performance negatively. Firstly, the need for a technique to distinguish between question and non-question utterances to reply with a more suitable response depending on the utterance’s type (question and non-question based utterances). Secondly, the need for a technique to handle an utterance targeting many topics that require firing many rules at the same time. Therefore, in this paper, the “Enhanced ArabChat” will cover these enhancements to improve the ArabChat’s performance. A real experiment has been done in Applied Science University in Jordan as an information point advisor for their native Arabic students to evaluate the Enhanced ArabChat
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