68 research outputs found
Social Networks Influence Analysis
Pew Research Center estimates that as of 2014, 74% of the Internet Users used social media, i.e., more than 2.4 billion users. With the growing popularity of social media where Internet users exchange their opinions on many things including their daily life encounters, it is not surprising that many organizations are interested in learning what users say about their products and services. To be able to play a proactive role in steering what userâs say, many organizations have engaged in efforts aiming at identifying efficient ways of marketing certain products and services, and making sure user reviews are somewhat favorable. Favorable reviews are typically achieved through identifying users on social networks who have a strong influence power over a large number of other users, i.e. influential users.
Twitter has emerged as one of the prominent social network services with 320 million monthly active users worldwide. Based on the literature, influential Twitter users have been typically analyzed using the following three models: topic-based model, topology-based model, and user characteristics-based model. The topology-based model is criticized for being static, i.e., it does not adapt to the social network changes such as userâs new posts, or new relationships. The user characteristics-based model was presented as an alternative approach; however, it was criticized for discounting the impact of interactions between users, and usersâ interests. Lastly, the topic-based model, while sensitive to usersâ interests, typically suffers from ignoring the inclusion of inter-user interactions.
This thesis research introduces a dynamic, comprehensive and topic-sensitive approach for identifying social network influencers leveraging the strengths of the aforementioned models. Three separate experiments were conducted to evaluate the new approach using the information diffusion measure. In these experiments, software was developed to capture usersâ tweets pertinent to a topic over a period of time, and store the tweetâs metadata in a relational database. A graph representing users was extracted from the database. The new approach was applied to the usersâ graph to compute an influence score for each user.
Results show that the new composite influence score is more accurate in comprehensively identifying true influential users, when compared to scores calculated using the characteristics-based, topic-based, and topology-based models. Also, this research shows that the new approach could leverage a variety of machine learning algorithms to accurately identify influencers.
Last, while the focus of this research was on Twitter, our approach may be applicable to other social networks and micro-blogging services
Engendering sustainable development competencies in higher education: The case of Egypt
© 2020 Elsevier Ltd Higher Education Institutions are a crucial player in achieving the international 2030 sustainable development agenda on the national levels. This study examines the role that Cairo University plays in promoting sustainable development competencies (a vital goal identified by the United Nations) through its formal and non-formal educational practices. This investigation represents the initial empirical effort that explores the promotion of sustainable development competencies in the Middle East. Specifically, it contributes to the literature by investigating factors that affect sustainable development competencies and by utilizing a Middle Eastern context. Finding reveals that there is a significant difference in the level of sustainable development competencies between students in different majors and colleges
Framing the role of higher education in sustainable development: a case study analysis
Purpose
Higher education institutions (HEIs) should play a fundamental role in achieving the international 2030 sustainable development (SD) agenda. Quality education is the fourth of the sustainable development goals (SDGs), and one of the targets related to this is to ensure that by 2030 all learners acquire the knowledge and skills needed to promote SD. Therefore, the SDGs provide a motive for HEIs to integrate SD concepts into their day-to-day practices. This study aims to introduce a framework for HEIsâ sustainable development assessment. Such a framework guides HEIs and educational leaders to support their countriesâ commitments to achieving the SDGs.
Design/methodology/approach
This paper presents the results of a case study analysis of the role and successful techniques of HEIs in achieving SD in three countries, namely, Germany, Japan and Egypt. Primary data was collected by semi-structured interviews with three Cairo University officials, while secondary data was collected by reviewing the universities\u27 official websites, reports, publications and related papers. This study introduces a novel framework for HEIs\u27 SD analysis and assessment, which guides HEIs and educational leaders to support SD to fulfill their countries\u27 commitments to achieving the SDGs. This framework is based on the following five categories: strategic direction and institutional working practices, supporting students, supporting university staff competencies, supporting society\u27s stakeholders and networking and sustainable campus. Consideration is given to the potential role of HEIs to support SD in each of these areas.
Findings
Cairo University could learn from the novel and pioneer practices of the Leuphana University of LĂŒneburg, and the University of Tokyo to fill in the gaps it has in different roles. It can also put more effort into adopting the suggested higher education programs of Egypt\u27s Vision 2030.
Research limitations/implications
This paper is limited to a case analysis comparing three countries, Germany, Japan and Egypt. Second, this study has not considered school education, which is equally essential in countries\u27 SD.
Practical implications
HEIs can use the framework and the findings in this paper to evaluate their current roles in supporting SD, identify the gaps and take actions accordingly to address their weaknesses.
Originality/value
The paper compares three universities, one in each of the case study countries. It draws conclusions that identify ways in which the paper\u27s framework and findings can guide SD practice in HEIs internationally, especially those in the developing world
A case oriented study: Whole genome sequencing (WGS) on a wild urease negative Proteus mirabilis isolated from deep surgical site infection (SSI) at El Hussein University Hospital, Al Azhar University Cairo, Egypt
Background: Proteus mirabilias ( P. mirabilis) strains are motile Gram negativerods that colonize the humangastrointestinal tract and could be a source of nosocomial infections especially in immune compromised cancer patients. Proteus mirabilis is identified by its urease production as a major bacterial virulence especially in urinary tract infections. Aim: This study aimed to characterize a case of a urease negative P. mirabilis isolated from a cancer patient suffering from deep surgical site infection. Methods: Conventional biochemical tests performed on swarming bacterial growth cultures were characteristic of P. mirabilis except for urease production. Identification was confirmed by Vitek-2 compact system and Vitek- MS. Dienes test proved the isolate is antigenically different from other urease positive P. mirabilis. Whole genome sequencing (WGS) identified this P. mirabilis strain with the seven encoding urease genes ureABCDEFG as well as their positive regulator gene UreR. Results: Mutations were found within amino acid sequences of UreB, UreE, UreF and UreG and UreR. Antibiotic sensitivity as well as WGS identified resistance genes to multiple classes of antibiotics. Conclusion: This is the first report of a wildly existed urease negative P. mirabilis due to mutations in the urease gene cluster (UreABC) as well as the regulator UreR. Questions are raised towards the urease enzyme as a key virulence factor to P. mirabilis. Other virulence factors that allow this species to cause other severe infections should be considered. The rate of isolation of urease negative P. mirabilis should be monitored and assessed in the future
Helicobacter pylori Western cagA genotype in Egyptian patients with upper gastrointestinal disease
Background: Infection with Helicobacter pylori (H. pylori) causes persistent gastritis that may progress to fatal gastric cancer. The cytotoxin-associated gene A protein (CagA), encoded by the cytotoxin-associated gene A (cagA) is the main virulence factor associated with more severe clinical outcomes. It is further divided into Western-type CagA and East Asian-type CagA. The East Asian-type CagA induces more cytoskeleton changes and is more likely to be associated with gastric cancer.Aim of the study: In the current study we aimed to identify the most prevalent H. pylori cagA genotype among Egyptian patients suffering from dyspepsia and to examine its possible correlation with the associated clinical condition.Patients and methods: Four biopsies were obtained from the antrum and angularis from each of 113 adult patients, who underwent upper endoscopy at the Endoscopy Unit, Theodor Bilharz Research Institute (TBRI) Hospital for the analysis of H. pylori by rapid urease test and detection of 16S rRNA. Nested PCR assay was used to determine cagA genotype.Results: Sixty (53.1%) dyspeptic patients were found infected with H. pylori. Although Egypt has a high prevalence of H. pylori infection, low prevalence of cagA was detected (26.5%). Western type cagA is the predominant type (62.5%) while East Asian type was not detected and others (37.5%) remain uncharacterized. Western-genotype cagA genotype was found in 80% of patients with peptic ulcer disease and 40% of patients with gastritis.Conclusion: Absence of the more virulent East Asian cagA genotype, which is the strongest risk factor for gastric carcinogenesis, may explain the very low gastric cancer rate among Egyptian population compared to other parts of the world. This finding demands further molecular studies using whole genome sequencing and more samples to determine the exact uncharacterized cagA genotype to identify the actual risk in developing gastroduodenal diseases in Egypt.Keywords: Helicobacter pylori, Endoscopic findings, Western type cagA, East-Asian cagA, Peptic ulcer, Gastriti
Effects of administration of 10 nm or 50 nm gold nanoparticles (AuNPs) on blood profile, liver and kidney functions in male albino rats
This work aimed to investigate the effect of acute and chronic administration of gold nanoparticles (GNPs) on liver and kidney functions, blood glucose concentration, lipid profile, and haematological parameters in male albino rats. Two experiments were conducted. In acute study: Fifty-four adult mature male rats were randomly assigned into three equal groups (18 per group). Group 1 (control group): in which rats were received intramuscular (i.m) injection of 1 ml normal saline 0.9%. Group 2 (50 nm GNPs group): rats were i.m. injected with a single dose of 75 ”g 50 nm GNPs/kg body weight (bwt). In Group 3 (10 nm GNPs group): rats were i.m. injected with a single dose of 75 ”g 10 nm GNPs/kg bwt. In chronic study: Eighteen adult male rats were randomly divided into three equal groups (6 per group). Group Р(control): rats were intramuscular (i.m) repeatedly injected with 1 ml normal saline 0.9% once/week 5 for weeks. Group 2 (50 nm GNPs): rats were i.m. injected with once/week with a dose of 75 ”g 50 nm GNPs/kg bwt) for 5 weeks. In Group 3 (10 nm GNPs): male rats were i.m. injected with once/week with a dose of 75 ”g 50 nm GNPs/kg bwt for 5 weeks, followed by 3 weeks washout period for all groups. Blood was collected at 3, 7, and 60 days in acute experiment, while, they were collected only before and after 2 months in chronic experiment. Acute and chronic administration of GNPs (10 or 50 nm size) in male albino rats induced no significant alterations for liver and kidney functions, lipid profile parameters and different haematological parameters at days 3 and 60 of the study. However, on day-7 post-treatment, GNPs-treated rats showed significantly (P <0.05) higher serum ALT, AST, ALP, urea, creatinine, glucose, and different lipid profile and decreased HDL level. Chronic administration of 10 nm or 50 nm GNPs significantly (P <0.05) decreased serum glucose levels. In conclusion acute or chronic administration of 10 nm or 50 nm GNPs could alter the liver, kidney functions and blood profile on day 7 post-treatment, however, these values returned to the normal levels on day 60 post- injection. Also, the chronic administration of GNPs induced a hypoglycemic effect in male albino rats
Development of insect resistant maize plants expressing a chitinase gene from the cotton leaf worm, Spodoptera littoralis
Due to the importance of chitinolytic enzymes for insect, nematode and fungal growth, they are receiving attention concerning their development as biopesticides or chemical defense proteins in transgenic plants and as microbial biocontrol agents. Targeting chitin associated with the extracellular matrices or cell wall by insect chitinases may be an effective approach for controlling pest insects and pathogenic fungi. The ability of chitinases to attack and digest chitin in the peritrophic matrix or exoskeleton raises the possibility to use them as insect control method. In this study, an insect chitinase cDNA from cotton leaf worm (Spodoptera littoralis) has been synthesized. Transgenic maize plant system was used to improve its tolerance against insects. Insect chitinase transcripts and proteins were expressed in transgenic maize plants. The functional integrity and expression of chitinase in progenies of the transgenic plants were confirmed by insect bioassays. The bioassays using transgenic corn plants against corn borer (Sesamia cretica) revealed that ~50% of the insects reared on transgenic corn plants died, suggesting that transgenic maize plants have enhanced resistance against S. cretica
Efficacy and Safety of Topical Tranexamic Acid Alone or in Combination with Either Fractional Carbon Dioxide Laser or Microneedling for the Treatment of Melasma
Introduction:Â Tranexamic acid (TXA) is a promising treatment modality for melasma. Microneedling (MN) and fractional carbon dioxide (CO2) laser were reported to enhance TXA transepidermal delivery.
Objectives:Â To compare efficacy and safety of topical TXA alone or in combination with either fractional CO2 laser or MN for treatment of melasma.
Methods:Â Thirty females with facial melasma were divided randomly into 3 equal groups after excluding pregnant and lactating women and those using oral contraceptives or other hormonal therapy. Patients of group A were treated with fractional CO2 laser and those of group B were treated with MN (4 sessions, 3 weeks apart for both) with immediate topical application of TXA 5% solution after sessions and daily application of 5% TXA cream for both groups. Patients of group C were treated by topical daily application of TXA 5% cream. Evaluation was done by modified melasma area and severity index scores (mMASI), patient satisfaction and dermoscopy.
Results: Statistically significant improvement of mMASI was reported in all studied groups with a significantly better improvement in patients of groups A and B than those of group C, meanwhile the difference between groups A and B was statistically insignificant.
Conclusions: Topical TXA is a safe and fairly effective treatment modality for facial melasma. Combining TXA with either fractional CO2 laser or MN yielded significantly better improvement than when used alone. Fractional CO2 laser carries the risk of post-inflammatory hyperpigmentation in patients with skin types III and IV and requires meticulous patient selection
Effect of Novel Quercetin Titanium Dioxide-Decorated Multi-Walled Carbon Nanotubes Nanocomposite on Bacillus subtilis Biofilm Development
The present work was targeted to design a surface against cell seeding and adhering of bacteria, Bacillus subtilis. A multi-walled carbon nanotube/titanium dioxide nano-power was produced via simple mixing of carbon nanotube and titanium dioxide nanoparticles during the sol-gel process followed by heat treatment. Successfully, quercetin was immobilized on the nanocomposite via physical adsorption to form a quercetin/multi-walled carbon nanotube/titanium dioxide nanocomposite. The adhesion of bacteria on the coated-slides was verified after 24 h using confocal laser-scanning microscopy. Results indicated that the quercetin/multi-walled carbon nanotube/titanium dioxide nanocomposite had more negativity and higher recovery by glass surfaces than its counterpart. Moreover, coating surfaces with the quercetin-modified nanocomposite lowered both hydrophilicity and surface-attached bacteria compared to surfaces coated with the multi-walled carbon nanotubes/titanium dioxide nanocomposite
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