Edwards Curves and Gaussian Hypergeometric Series

Let $E$ be an elliptic curve described by either an Edwards model or a twisted Edwards model over $\mathbb{F}_p$, namely, $E$ is defined by one of the following equations $x^2+y^2=a^2(1+x^2y^2),\, a^5-a\not\equiv 0$ mod $p$, or, $ax^2+y^2=1+dx^2y^2,\,ad(a-d)\not\equiv0$ mod $p$, respectively. We express the number of rational points of $E$ over $\mathbb{F}_p$ using the Gaussian hypergeometric series $\displaystyle {_2F_1}\left(\begin{matrix} \phi&\phi {} & \epsilon \end{matrix}\Big| x\right)$ where $\epsilon$ and $\phi$ are the trivial and quadratic characters over $\mathbb{F}_p$ respectively. This enables us to evaluate $|E(\mathbb{F}_p)|$ for some elliptic curves $E$, and prove the existence of isogenies between $E$ and Legendre elliptic curves over $\mathbb{F}_p$

On large FF-Diophantine sets

Let $F\in\mathbb{Z}[x,y]$ and $m\ge2$ be an integer. A set $A\subset \mathbb{Z}$ is called an $(F,m)$-Diophantine set if $F(a,b)$ is a perfect $m$-power for any $a,b\in A$ where $a\ne b$. If $F$ is a bivariate polynomial for which there exist infinite $(F,m)$-Diophantine sets, then there is a complete qualitative characterization of all such polynomials $F$. Otherwise, various finiteness results are known. We prove that given a finite set of distinct integers $S$ of size $n$, there are infinitely many bivariate polynomials $F$ such that $S$ is an $(F,2)$-Diophantine set. In addition, we show that the degree of $F$ can be as small as $\displaystyle 4\lfloor n/3\rfloor$

Automatic Classification of Bright Retinal Lesions via Deep Network Features

The diabetic retinopathy is timely diagonalized through color eye fundus images by experienced ophthalmologists, in order to recognize potential retinal features and identify early-blindness cases. In this paper, it is proposed to extract deep features from the last fully-connected layer of, four different, pre-trained convolutional neural networks. These features are then feeded into a non-linear classifier to discriminate three-class diabetic cases, i.e., normal, exudates, and drusen. Averaged across 1113 color retinal images collected from six publicly available annotated datasets, the deep features approach perform better than the classical bag-of-words approach. The proposed approaches have an average accuracy between 91.23% and 92.00% with more than 13% improvement over the traditional state of art methods.Comment: Preprint submitted to Journal of Medical Imaging | SPIE (Tue, Jul 28, 2017

Frontoorbital advancement in coronal suture craniosynostosis: a quantitative preoperative assessment

Background Surgical therapy of coronal craniosynostosis in the modern era has evolved with the adoption of frontoorbital advancement and forehead reshaping to correct the supraorbital rim recession and the abnormal form of the cranium. The aim of this study was to evaluate the efficiency of quantitative preoperative planning for the degree of frontoorbital advancement in treatment of coronal craniosynostosis.Patients and methods Fourteen patients (eight bilateral and six unilateral cases) who presented with simple nonsyndromic coronal craniosynostosis were treated surgically at the Plastic Surgery Unit in Zagazig University Hospital. The degree of the needed frontoorbital advancement was determined preoperatively using longitudinal orbital projection. Standard surgical correction was performed in all cases including frontoorbital advancement and forehead reshaping. Follow-up was based on clinical examination, computed tomography, and longitudinal orbital projection.Results The preoperative and postoperative longitudinal orbital projection documented significant improvement in the relationship between the supraorbital rim and the cornea in all cases, with normalization of the relationship between the supraorbital rim and the cornea in eight patients (five patients were bilateral, and three patients were unilateral).Conclusion Frontoorbital advancement and forehead reshaping for treatment of bilateral and unilateral coronal craniosynostosis achieve excellent functional and aesthetic results. Quantitative preoperative planning to determine the degree of frontoorbital advancement is highly recommended to achieve significant improvement and normalization of the relationship between the supraorbital rim and the cornea.Keywords: coronal craniosynostosis, frontoorbital advancement, forehead reshapin

Causes of variation orders in the Egyptian construction industry: Classification, ranking, and mitigation

Variations or change orders are inevitable in any construction project. They are defined as any change that happens in the scope of the project whether this change is an additional scope of work, omission, or even alteration. This thesis presents the causes of variation orders in Egypt. The literature review divides the causes into four main categories: owner related, contractor related, consultant related, and other causes. All the identified events were surveyed in a questionnaire given to top executives in the construction field in Egypt. The survey was distributed equally on clients, consultants, and contractors. The top 10 most important causes are ranked among the opinion of each party. Another list of the least 10 important causes of variation orders is presented as well. It was found out that when adding up all the results, the most important cause of variations is that the client instructs additional work, followed by contractor using grey areas in the contract to request variations, and continuous changes in schedule. A comparison was done between Egypt, Palestine, Malaysia, and the United Kingdom. It was found it that problems related to design are mentioned directly or indirectly in every country, but there is no overall similarity when comparing all the countries against each other. Further to data analysis, a model was created using the collected data base. This model provides the user with a scale that predicts the effect of the events triggering variations on both project cost and time. The model was validated using a case study about a large retail shopping center that was recently completed and has proven to be helpful. Finally, the research also provides a list of mitigation techniques that can help reduce the events that give rise to variations. The list of recommendation was validated through a survey given to professionals in the industry to insure their authenticity for the thesis

Global mobility with universal identity (GMUI)

The emerging needs of operators to enhance the users\u27 mobility and to increase their productivity, have raised a need for an architecture that can facilitate the ability of mobile users to conduct business anywhere, anytime, from any device with the same amenities offered in their home networks. The escalation of cyber attacks enforces any technology underpinning mobility to span the spectrum of network services with integral security capabilities to protect both the mobile users and the enterprise network. This thesis proposes an architecture to securely enhance users\u27 mobility. The architecture extends the capabilities of standard mobile IP, solves its applicability problems, and links mobile users\u27 activities to unique universal identities. The universal identity is achieved by associating mobile user\u27s credentials as IP, hostname, and network equipment identifiers (ex. network cards or mobile sets) with his (U)SIM (Universal subscriber identity module). The global mobility concept proposed is achieved by adopting a new hierarchical mobile IP (MIP) architecture that enables subscribers to maintain the connections to their corporate and to the internet while moving across hybrid infrastructure without impacting their existing connections except with minimum handover time. The main advantages of the new mobile IP concept is its scalability inherited from its hierarchical distributed design making it suitable for small ISP as well as enterprise carrier crossing the countries boundaries while preserving the security policy of the various entities. The second advantage is the enhancement of the new MIP concept with a strong security mechanism that protects against identity spoofing. The third advantage is its independence of the access media or the used equipment to enhance the users\u27 mobility while avoiding loading equipments with complex applications. Finally, the architecture adopts a secure encrypted hierarchal method for message passing, route finding and addresses the security limitation of standard internet protocols. The architecture operation and advantages have been verified with fourteen experiments to test the interaction between its eight distributed services, the corresponding node\u27s communications with a mobile user roaming at different locations, and the users\u27 mobility features including the mobile user\u27s IP and network cards handover capabilities

Impact of ridge–furrow water harvesting system on faba bean (Vicia faba L.) production under rainfed conditions in Matrouh, Egypt

AbstractIn the North Western Coastal Zone (NWCZ) of Egypt, low rainfall results in poor crop production. Different techniques should be examined to enhance the crop yield productivity and increase the water use efficiency. The ridge–furrow water harvesting system (RFWHS) is examined under the rainfed conditions in the NWCZ of Egypt over the two growing seasons of 2012/2013 and 2013/2014. Two ridge:furrow ratios of 120:60 and 60:60cm ridge:furrow were used and compared to the conventional cultivation in a flat plot. The RFWHS was combined with different plant densities produced from three different row spacing (i.e., 20, 30, 60cm). The faba bean yield was highly influenced by the ridge:furrow ratio, the seed yield was increased by 47% and 128.2% when the 60:60cm ridge:furrow ratio was used as compared to the conventional cultivation in the first and second seasons, respectively. The row spacing of 30cm apart produced the highest seed yield of 491.1kg/ha in the first season and 261.3kg/ha in the second season as compared to 20cm and 60cm row spacing. The water use efficiency followed the same pattern as that of seed yield; it was the highest for the 60:60cm ridge:furrow ratio and the highest for the 30cm row spacing. It is concluded that the RFWHS can be used effectively in increasing faba bean production and maximizing water use efficiency in limited rainfall areas

Effect of Expressive Arts Therapy Interventions on Comfort of Children Undergoing Surgery

Context: Children undergoing surgery may experience pain and discomfort. Unfortunately, it is not always possible to completely prevent postoperative pain and discomfort with analgesics. Therefore, there is an increasing interest in non-pharmacological interventions through expressive arts therapy.Aim: This study aimed to evaluate the effect of expressive arts therapy interventions on the comfort of children undergoing surgery. Methods: A quasi-experimental design was utilized in this study. This study was conducted at the Pediatric Surgical Department in Children's Hospital affiliated to Ain Shams University, Cairo, Egypt, on a purposive sample of 84 children undergoing surgery. Children were randomly assigned to two equal groups (control group 42 and study group 42). A child's assessment record was used to gather data related to the characteristics of the studied children and surgery data. Pain assessment record to assess the child's physiological and physical parameters of pain. A Numeric Pain Rating Scale to assess a child's pain intensity. State-Trait-Anxiety Inventory for Children to measure anxiety levels. Besides, A Comfort Assessment Scale to assess children's numerical pain intensity and discomfort. Results: There are statistically significant differences in mean pain intensity scores were observed between the control and study groups on the second day after surgery and before discharge (p > 0.05). The mean anxiety scores were significantly lower in the study group compared to the control group on the day after surgery and before discharge (p < 0.05). Also, there were observed improvements in mean comfort scores between the study and the control group on the day after surgery scores and on the day of discharge with a statistically significant difference (p < 0.05). There were statistically significant differences at (p-value=0.000) between children in the control and study group regarding children's postoperative pain intensity, anxiety levels, and comfort scores. Conclusion: The application of expressive arts therapy interventions was positively improving comfort and reducing pain intensity and anxiety levels among children undergoing surgery in the study group compared to the controls, emphasizing the importance of using expressive arts therapy interventions for improving children's postoperative comfort

Resilience of a Palestinian University Instructor Surviving War: A Grounded Theory Study

This qualitative study addressed the devastating impacts of war on civilians by giving voice to a Palestinian university instructor who had a life-threatening experience during the Israeli aggressive war on the Gaza Strip in 2014. The data for the study were gathered from two different sources: (i) a narrative written by the instructor shortly after his recovery and (ii) a semi-structured interview conducted with him three years after this harrowing event. In order to explore and theorize the salient themes in the data, we adopted a three-phase grounded theory methodology. The initial coding phase yielded 30 important codes, which were compared and appraised in the focused coding phase, and three core categories could be identified: adversities, adaptive factors, and positive outcomes. Finally, the theoretical coding phase revealed resilience as the best fitting theoretical perspective to interpret the instructor’s lived experiences before, during, and after his miraculous survival. We concluded the study with a discussion of its limitations, significance, and implications