Drug Design and Development of Antivirals and Fluorescent Anion Transporters

The application of medicinal chemistry drug design and development principles has been undertaken in the current thesis towards the development of antivirals, fluorescent anion transporters and carbonic anhydrase inhibitors. Chikungunya viral infection is an increasing concern with no current treatments available beyond supportive measures. In the absence of detailed viral molecular information, phenotypic screening of compounds has provided leads for anti-chikungunya agents. Chapter 2 discusses the application of hybridization of two fragments, namely pyrimidine and thiazolidine, with reported anti-CHIKV activity. Convergent and convenient regioselective synthesis of novel thiazolo[2,3-a]pyrimidine derivatives was accomplished using the one-pot reaction of 6-ethylthiouracil, bromoacetic acid, anhydrous sodium acetate, acetic anhydride, acetic acid and a suitable aldehyde. X-ray crystallographic studies reveal the presence of the Z configuration of only one regioisomer confirmed by computational studies as being the most likely isomer present. Anti-CHIKV activity evaluation showed the tailed thiazolopyrimidine (Z)-7-ethyl-2-((4\u27-methyl-[1,1\u27-biphenyl]-4-yl)methylene)-5H-thiazolo[3,2-a]pyrimidine-3,5(2H)-dione as a candidate for future development with EC50 = 42 μM, and IC50 \u3e 250 μM against the breast cancer cell line MCF-7 and the endothelial human sapiens cell line EA.hy926..

Detection of metallic and plastic landmines using the GPR and 2-D resistivity techniques

International audienceLow and non-metallic landmines are one of the most difficult subsurface targets to be detected using several geophysical techniques. Ground penetrating radar (GPR) performance at different field sites shows great success in detecting metallic landmines. However significant limitations are taking place in the case of low and non-metallic landmines. Electrical resistivity imaging (ERI) technique is tested to be an alternative or confirmation technique for detecting the metallic and non-metallic landmines in suspicious cleared areas. The electrical resistivity responses using forward modeling for metallic and non-metallic landmines buried in dry and wet environments utilizing the common electrode configurations have been achieved. Roughly all the utilized electrode arrays can establish the buried metallic and plastic mines correctly in dry and wet soil. The accuracy differs from one array to the other based on the relative resistivity contrast to the host soil and the subsurface distribution of current and potential lines as well as the amplitude of the noises in the data. The ERI technique proved to be fast and effective tool for detecting the non-metallic mines especially in the conductive environment whereas the performances of the other metal detector (MD) and GPR techniques show great limitation

Assessment Performance of 3-Parameter Probability ‎Distributions for At-site Annual Streamflow in the ‎Blue Nile Basin ‎

Many investigators have been applied various probability distributions for flood discharges at-site or region, however, there is no scientific judge about the best distribution to accurate the flood discharge estimations. In practice, different probability distributions are taken into account, and the best distribution is then applied to create the percentile quantiles. This paper introduces the assessment of three probability distributions that have three parameters; Generalized Extreme Value (GEV), Generalized Pareto (GPA) and Generalized Logistic (GLO) using L-moments (LM) method to estimate their parameters using annual peak discharge series of three hydrological stations on Blue River Basin and Atbara River in Sudan. Cunnane plotting position formula is considered to test the applicable probability distribution that gives good estimations in tails. The Q-Q relation with coefficient of determination (R2) is adopted to present the consistency process of the estimates and their corresponding of observed annual peak data. L-moment ratio diagram (LMRD) as suggested by Hosking and Walish (1993) is also performed to measure the discordance of probability distributions. Further, the evaluation performance of probability distributions can be measured by using three comparison criteria; root mean square error (RMSE), mean absolute deviation index (MADI) and relative root mean square error (RRMSE). The results indicated that GLO distribution generally shows the best fit followed by GEV distribution; however the GEV distribution gave more realistic in upper tail than others. It may be recommended as the appropriate probability distribution for annual peak discharge at-site in Blue Nile

A study of groundwater contamination and bioremediation treatment using natural soil and vegetation

This thesis is concerned with the following studies : 1- Ammonium analysis in soil and water including the determination of low levels of ammonium (<0.1 mg N/1) in groundwater and the colorimetric analysis of highly coloured groundwater samples. 2- An investigation of groundwater quality and soils at a contaminated industrial site. 3- Bioremediation treatment of the ammonium and nitrate contaminated groundwater using natural soil and vegetation and using soil incubation and pot experiments. These findings of a pot experiment suggest the possibility of applying the bioremediation treatment of the ammonium and nitrate contaminated water in the field. A field study should be undertaken to evaluate the efficiency of this bioremediation treatment. This field study would require a suitable uniform area to lay out the plots, preferably close to the source of water to be used. In addition, it is necessary to carry out a hydrological survey to determine the following aspects: 1-The size of groundwater reservoir. 2-The rate of removal of the water. 3-The time scale of the water application. The climatic conditions such as rainfall, potential evapotranspiration and temperature should be taken into consideration when carrying out the bioremediation treatment in the field as these climatic conditions affect the water requirements and the growth of grass. There are three options to apply the contaminated groundwater as follows : 1-To apply the contaminated groundwater at low or high volume depending on its level of nitrogen. 2-To blend well water with high level of nitrogen with well water with low level of nitrogen to achieve a realistic irrigation rate at a suitable nitrogen level. 3-To overirrigate in expectation that ammonium would be retained in the soil. The ryegrass used in this bioremediation treatment can be disposed of by incineration and landfilling the ash or landfilling the grass

Characterization of Macro-Scale and Meso-Scale Performance of Asphalt Concrete Mixtures Under Compression

Researchers at Texas A&M University have developed the Pavement Analysis using Nonlinear Damage Approach (PANDA) for predicting the performance of asphalt concrete mixtures. PANDA offers substantial improvements in mechanistic modeling and simulation of pavement performance over other existing approaches. However, in order to facilitate the use of PANDA, there is a need to develop a systematic approach for determining the input parameters of its constitutive models. In this dissertation, a well-designed experimental testing protocol is developed to characterize the resistance of asphalt concrete mixtures to permanent deformation. This approach involves conducting two experimental tests in order to extract the PANDA model parameters: the dynamic modulus test (DMT) and repeated creep-recovery test at various stresses (RCRT-VS). Then, a systematic analytical approach is used to determine the linear viscoelastic, nonlinear viscoelastic, and viscoplastic PANDA model parameters for different types of asphalt mixtures and at different temperatures, air void contents, and aging levels. The analytical method employs DMT data to determine the long-term linear viscoelastic properties and time-temperature shift factors, and it employs the RCRT-VS data to determine the nonlinear viscoelastic and viscoplastic properties. A significant part of this dissertation focuses on the implementation of the global sensitivity analysis (GSA) approach to determine the sensitivity of the asphalt mixture performance to the PANDA’s input parameters. This analysis is performed in order to reduce the output uncertainty to input uncertainty, focus the experimental methods on evaluating the key parameters that influence performance, and simplify the analytical approach to extract significant model parameters from experimental data. The GSA results show that the viscoelastic nonlinearity parameter (g2), viscoplastic hardening function parameters (k1 and k2), and viscoplasticity-relaxation time (1/ Гvp) are the most significant and sensitive parameters. The PANDA constitutive modeling framework is used to efficiently simulate and predict the viscoelastic and viscoplastic responses of asphalt pavements. Two different scales of asphalt mixture performance are investigated: macro-scale (full dense-graded mixture, DGM) and meso-scale (fine aggregate matrix, FAM, and coarse aggregate matrix, CAM). The computational results show that the FAM controls the viscoelastic response of asphalt mixtures, while the CAM properties primarily influence the viscoplastic response of asphalt mixtures

The Impact of Learning Management System Usage on Cognitive and Affective Performance

1 INTRODUCTION Since learning management systems (LMSs) are offering a great variety of channels and workspaces to facilitate information sharing and communication among learners during learning process, many educational organizations have adopted a specific LMS into their educational context. A LMS is a software that handles learning tasks such as creating course catalogs, registering students, providing access to course components, tracking students within courses, recording data about students, and providing reports about usage and outcomes to teachers [1]. LMSs include several applications such as OLAT, WebCT, Moodle, ATutor, Ilias, and Claroline. However, LMSs can be utilized to integrate a wide range of multimedia materials, blogs, forums, quizzes, and wikis. Therefore, the researchers suggest that studying the influence of technology usage on end-users, especially students, is fundamental in learning and teaching environment. Despite educational organizations routinely make decisions regarding the best pedagogical approaches for supporting students’ performance, there is very little research on the impact of LMSs on learning outcomes [2]. Indeed, a considerable number of studies were conducted to examine the adoption of various LMSs, whereas little researches focused on understanding how educational institutes can enhance learning and teaching process through a particular LMS [3]. Consistent with this, the researchers found virtually no research on investigating the relationship between LMSs usage and attitude toward learning. [...

A Study of Three Unpublished Mausoleum Domes in Mit Ghamr City (Dakahlia Governorate)

This study examines the architectural archaeological analysis of three remaining mausoleum domes in Mit Ghamr City, which are the Domes of Sidi Khalaf, Arbaeen and al-Wa’ez. The importance of this study lies in shedding light on these domes, revealing their architectural and decorative elements.This study is also an attempt to date these domes based on the oldest references to them in the documents so far and on a translation found for one of the owners of these mausoleum domes. This is in addition to tracing the different architectural elements of these three domes, in assimilation with other domes, whether in Cairo or the Delta cities, in different eras, in order to arrive at the accurate date of establishment of these domes.The study tackles the architectural analysis of the different architectural elements of the three mausoleum domes to proceed with the architectural development of the domes of the Delta cities in general.A documentary analytical archeological studyIt is worth noting that despite the archaeological importance of these domes, they are not registered in the census of Islamic and Coptic antiquities. The lack of registration had a great impact on the infringement of these domes by the people, as well as the residential encroachment that surrounded Arbaeen and al-Wa’ez Domes, which naturally led to concealing many of their architectural details. This represented a difficulty in studying these mausoleum domes and in taking their pictures with the required accuracy, for it was often swiftly done. Therefore, the study recommended the necessity of registering these domes due to their architectural and decorative importance, and for their distinctiveness in having some important architectural elements that assist in tracing the historical graph of the development of mausoleum domes in Egypt during the different Islamic eras

Characterization of Macro-Scale and Meso-Scale Performance of Asphalt Concrete Mixtures Under Compression

Researchers at Texas A&M University have developed the Pavement Analysis using Nonlinear Damage Approach (PANDA) for predicting the performance of asphalt concrete mixtures. PANDA offers substantial improvements in mechanistic modeling and simulation of pavement performance over other existing approaches. However, in order to facilitate the use of PANDA, there is a need to develop a systematic approach for determining the input parameters of its constitutive models. In this dissertation, a well-designed experimental testing protocol is developed to characterize the resistance of asphalt concrete mixtures to permanent deformation. This approach involves conducting two experimental tests in order to extract the PANDA model parameters: the dynamic modulus test (DMT) and repeated creep-recovery test at various stresses (RCRT-VS). Then, a systematic analytical approach is used to determine the linear viscoelastic, nonlinear viscoelastic, and viscoplastic PANDA model parameters for different types of asphalt mixtures and at different temperatures, air void contents, and aging levels. The analytical method employs DMT data to determine the long-term linear viscoelastic properties and time-temperature shift factors, and it employs the RCRT-VS data to determine the nonlinear viscoelastic and viscoplastic properties. A significant part of this dissertation focuses on the implementation of the global sensitivity analysis (GSA) approach to determine the sensitivity of the asphalt mixture performance to the PANDA’s input parameters. This analysis is performed in order to reduce the output uncertainty to input uncertainty, focus the experimental methods on evaluating the key parameters that influence performance, and simplify the analytical approach to extract significant model parameters from experimental data. The GSA results show that the viscoelastic nonlinearity parameter (g2), viscoplastic hardening function parameters (k1 and k2), and viscoplasticity-relaxation time (1/ Гvp) are the most significant and sensitive parameters. The PANDA constitutive modeling framework is used to efficiently simulate and predict the viscoelastic and viscoplastic responses of asphalt pavements. Two different scales of asphalt mixture performance are investigated: macro-scale (full dense-graded mixture, DGM) and meso-scale (fine aggregate matrix, FAM, and coarse aggregate matrix, CAM). The computational results show that the FAM controls the viscoelastic response of asphalt mixtures, while the CAM properties primarily influence the viscoplastic response of asphalt mixtures

Military Service in Eritrea

openThis study aims to analyse the human rights violations in the military service in Eritrea in details and to investigate how the international community as major power countries and international organisations as the United Nations react in response to these violations committed by the Eritrean government. The thesis starts with providing a country overview about Eritrea and the history of the country and its demographic distribution, then it is followed with a brief history of military service laws in different countries during the world wars and afterwards. After the brief introduction about Eritrea and military service, the thesis examines in details military service in Eritrea by discussing the history of the military service in Eritrea, and the laws that regulate the military service. Afterwards, a detailed description of the reality of the military service in Eritrea is found, and a description of the experiences of those conscripted, the draft evaders and the draft deserters and also their families. In addition, the experiences of vulnerable people as women and children is also assessed Further in the thesis, the journey of Eritreans to flee their country and seek asylum elsewhere due to the military service is also analysed. After an analysis of the current situation of the military service in Eritrea is done, the thesis investigates how the current reality in Eritrea is far from being inline with the country’s international obligations and how the international community has reacted in the face of these ongoing violations. The study eventually suggests international tools and laws that could be used by the international community in order to hold the Eritrean government responsible for these violations and sanction the decision-makers responsible