An Analysis of SCTP in Best-Effort Network With Competing Flows

This study focuses on Stream Control Transmission Protocol (SCTP), which is defined by IETF in RFC 4960 as a new transport protocol. SCTP features such as multi-homing and multi-streaming, has attracted multimedia applications to use it as their transport protocol instead of UDP and TCP. However, the challenge faced by SCTP is in a best-effort network, where the network does not provide any Quality of Service for the upper layer. In this study, a comprehensive performance evaluation of SCTP in the best-effort network in the presence of other traffic flows will be carried out. The objectives of this research are to measure the performance of both TCP and SCTP over a Wired Network in terms of delay, jitter, and throughput in a network environment that has STCP with UDP traffic, and then compare SCTP and TCP performance results in terms of these performance metrics. All experiments conducted in this research were obtained through network simulation tools, i.e. NS 2. It is expected that the results obtained will become useful for future researchers in improving SCTP

Suitability of Egyptian Deserts for Sustainable Urban Development

Egypt has limited cultivable land, its water resources are limited and its population is growing, which in turn is destroying the cultivable land. If these issues are not dealt effectively, Egypt will have a large scale food crisis in its hands. This study aims to identify the resources provided by the uninhabited Egyptian deserts, their potential and how they can be utilized. Most of the research has been undertaken online, including in-depth study of the characteristics of Egyptian soil and how their composition changes over time. The country will require undergoing massive amounts of change, especially when it comes to conserving water, as this will be the main source of development. Underwater aquifers need to be found and dug up, and recycling and modern irrigation techniques will need to be adapted.  A number of developmental projects have been put forward and some were initiated as well, however, due to mismanagement, these projects either failed or were not initiated. The government must learn from its previous mistakes and undertake the development of the Egyptian desert in stages, with proper quality assurance criteria. Keywords: Urban Development, Egyptian Deserts, Urban Planning, Sustainable Development

Motivations and attitudes of undergraduate students toward ESP classes in an Egyptian university

In the last few decades, English for Specific Purposes (ESP) has become one of the most needed sub-fields of English for Speakers of Other Languages (ESOL). In Egypt, ESP courses are widely taught in both public and private universities. Also, motivation and attitude play an essential role in how well a learner understands the suggested material in an educational environment. They are considered important factors which may have an effect on the ESP educational process in Egypt. Many studies have addressed the area of motivation and attitudes in the EFL context. However, after a thorough review of the literature available on this subject, there appears to be a scarcity in the research on ESP students\u27 motivations and attitudes in the Egyptian context. Based on the researcher\u27s 10 years of experience teaching ESP classes in addition to conducting a pilot study, there is a need for a study concerning ESP learners\u27 motivation and attitudes in Egypt. This study focuses on the motivations and attitudes of students in ESP classes in various academic years at a public university, Mansoura University. The study was guided by three research questions. The first investigated the types of motivation the students have when taking ESP classes and how much they are motivated toward them. The second explored the attitudes of undergraduate students toward ESP courses at Mansoura University. The third investigated whether students\u27 academic disciplines affect their motivation and attitudes toward ESP courses. The study adopted a mixed-methods exploratory applied design. The research involved 517 participants of non-English majors who were registered in undergraduate ESP courses in the 2014 spring semester at Mansoura University. Both quantitative and qualitative data were collected through their responses to a 4-point Likert scale questionnaire, multiple-choice format scales, open-ended questions, and a semi-structured interview. The results of the study showed that students are motivated both intrinsically and extrinsically in addition to having high motivational intensity and a deep interest toward ESP classes. The study also revealed that the students have a relatively positive attitude toward their ESP courses. However, there are several factors that affect the students\u27 attitudes such as unrelated course materials, inconvenient course schedules, lack of incorporation of educational technology into classroom instructions, poor teaching methods of the professors and instructors, or the learning environment that affect the students\u27 attitudes negatively. In addition, the results showed that the academic discipline is not considered an important factor that affects students\u27 motivation toward their ESP classes. However, a slight positive trend in the attitude of ESP students was shown in the present study which may arise from different conditions regarding the students\u27 goals and the conditions of different classes at different academic disciplines. The implications of this study may help the universities develop ESP courses in order to increase ESP students\u27 motivation and attitudes toward their ESP classes

A Novel Method for Compact Listing of All Particular Solutions of a System of Boolean Equations

Any system of ‘big’ Boolean equations can be reduced to a single Boolean equation . We propose a novel method for producing a general parametric solution for such a Boolean equation without attempting to minimize the number of parameters used, but instead using independent parameters belonging to the two-valued Boolean algebra B2 for each asserted atom that appears in the discriminants of the function . We sacrifice minimality of parameters and algebraic expressions for ease, compactness and efficiency in listing all particular solutions. These solutions are given by additive formulas expressing a weighted sum of the asserted atoms of , with the weight of every atom (called its contribution) having a number of alternative possible values equal to the number of appearances of the atom in the discriminants of . This allows listing a huge number of particular solutions within a very small space and the possibility of constructing solutions of desirable features. The new method is demonstrated via three examples over the ‘big’ Boolean algebras, , , and , respectively. The examples demonstrate a variety of pertinent issues such as complementation, algebra collapse, incremental solution, and handling of equations separately or jointly

The Issue of Urban Character in the Suez Canal Region: A Proposed Matrix for Developing the Area’s Urban Character in Light of the Egyptian State’s Development Plans

Because of its environmental, social and humanitarian dimensions, the problem of urban character and absence of identity and authenticity is one of the issues of greatest concern in urban planning. There are thus several justifications for this research, including the importance of urban character for Suez Canal cities and the significance of place-identity and local character in Arab cities at large. This paper aims to observe and report on actual urban conditions in some of the districts in the Suez Canal governorates and to propose recommendations to support the process of development and urban conservation in an effort to ensure the continuity of the distinctive urban character of built-up areas of value. The methodology adopted in the first section of this paper to observe and assess existing urban conditions involves making use of earlier research and field studies dealing with the cities of Port Said, Ismailia and Suez where built-up areas developed in a natural, planned manner according to the needs and limitations of the cities. The Suez Canal Company traversed the Suez Canal water barrier and built the district of Port Fouad on the east bank of the Canal, thus dividing the city’s built-up area into two districts or quarters: the eastern quarter (Al Sharq) and the western quarter (Al Gharb). (1)This paper also sheds light on the stages of growth and development of urban masses at different periods and examines the three growth axes in the cities concerned as well as the different types of land use. (2)The type of urban fabric, the characteristic attributes and the visual aspects of cities in the Suez Canal region are explored towards the end of the paper. Mixed residential land use is widespread while touristic, commercial and touristic / residential uses are concentrated mainly along the Mediterranean coast and (mixed with commercial land uses) eastward along the banks of the Suez Canal. Land use along the main streets of the cities is primarily residential / commercial – an attribute that has a visual and functional impact on city planning and that must therefore be taken into consideration by development plans and by all the parties involved in the planning process. (3) Keywords: Suez Canal Region – Urban Character – Port Said – Suez – Ismailia – Al Arab Quarter – Western Quarter – Architectural Characte

The association between Mitochondrial NADH Dehydrogenase (MTND3, MTND4L, MTND4) polymorphisms and male infertility

Male infertility has been related to many factors and about 15 - 30% of the cases are related to genetic predisposition. The purpose of the present study was to determine the relationship between infertility and the polymorphism of mitochondrial NADH dehydrogenase subunit 3, 4L, and 4 (MT-ND3, MT-ND4L, and MT-ND4) genes. Direct sequencing of the target genes in the mitochondrial DNA was carried out on semen samples of 68 subfertile and 44 fertile men. Forty single nucleotide polymorphisms in the MT-ND3, MT-ND4L, and MT-ND4 genes were identified and genotyped as follows: eight SNPs in MTND3 rs2853826, rs28435660, rs193302927, rs28358278, rs41467651, rs3899188, rs28358277 and rs28673954, seven SNPs in MTND4L rs28358280, rs28358281, rs28358279, rs2853487, rs2853488, rs193302933 and rs28532881, and twenty five SNPs in MTND4 in the cases and controls: rs2853495, rs2857284, rs2853496, rs2853497, rs3087901, rs2853493, rs2853490, rs3088053, rs2853491, rs2857285, rs28358282, rs28594904, rs28669780, rs28415973, rs28471078, rs55714831, rs28358283, rs75214962, rs28529320, rs2853494, rs28609979, rs28358286, rs28359168, rs28384199, and rs869096886. The genotypes frequencies of the study population showed that rs2853495 G>A (Gly320Gly) in the MT-ND4 gene was statistically associated with male infertility (P = 0.0351). In the allele frequency test, the results showed that rs2853495 G>A (Gly320Gly) and rs869096886 A>G (Leu164Leu) in MT-ND4 were significantly associated with male infertility (adjusted OR = 2.616, 95% CI = 1.374 - 4.983, P = 0.0028; adjusted OR = 2.237, 95% CI = 1.245 - 4.017, P = 0.0073, respectively). On the other hand, no statistically significant association difference was reported between the asthenozoospermia, oligozoospermia, teratozoospermia, asthenoteratozoospermia, oligoasthenoteratozoospermia, oligoteratozoospermia subgroups of subfertile males and the fertile ones. In conclusion, our findings suggested that male infertility was correlated to rs2853495 and rs869096886 SNPs in the MTND4 gene. More studies on the subfertile males in different populations are required to develop a clear understanding of the role of these SNPs in male infertility. In addition, functional studies will be very helpful to elucidate the molecular role of these SNPs in the function of these genes

3,4-Dichlorobenzoic acid biodegradation by the Edwardsiella tarda: Effect of Some Growth Conditions

The biodegradation of 3,4-DiChlorobenzoic acid was investigated by using Edwardsiella tarda and it used 3,4-DCBA as sole carbon and energy source. Several concentrations of 3,4-D CBAs (1mM, 2mM ,3mM ,4mM and 5mM) were used. The highest rate of degradation of 3,4-D CBAs was obtained at a concentration (2mM). The experiments were included substrate concentration, temperature, pH, starvation, adaptation, carbon and nitrogen sources. The degradation ability was monitored through the release of chloride disappearance of the substrate and finally the growth of bacterial cells on that substrate. The optimal temperature and pH for the bacteria were 42ºC and 7.5, respectively. Adaptation of the cells on 3,4-DCBA for 48 hours and cells starvation for 24 hours and 48 hours increasing the initial degradation rate. The carbon sources affected the 3,4 –DCBA degradation differently from that on chloride and cell mass production. Nitrogen sources supplied (yeast extract, L-proline, casein, NH4, K-Nitrate, arginine, urea and glycine). Urea and casine caused a repression in 3,4-DCBA degradation. Catechol 1,2 dioxygenase activity was found to be present in cell free extracts suggesting that 3,4-DCBA is catabolized by ortho-ring cleavage pathway

(R1454) On Reducing the Linearization Coefficients of Some Classes of Jacobi Polynomials

This article is concerned with establishing some new linearization formulas of the modified Jacobi polynomials of certain parameters. We prove that the linearization coefficients involve hypergeometric functions of the type 4F3(1). Moreover, we show that the linearization coefficients can be reduced in several cases by either utilizing certain standard formulas, and in particular Pfaff-Saalschütz identity and Watson’s theorem, or via employing the symbolic algebraic algorithms of Zeilberger, Petkovsek, and van Hoeij. New formulas for some definite integrals are obtained with the aid of the developed linearization formulas