المطرفي، وردة مبروك مساعد

The present study was undertaken using O. spilurus (Tilapia) because of its wide availability and suitability as a model for toxicity testing as well as they had exhibited a time-honored place in the economical nutrition. Chlorpyrifos is a broad-spectrum organophosphate for agriculture. Therefore, the purpose of the present study was to evaluate the effect of sublethal toxicity of organophosphate insecticide CPF (Dursban 48) on some organs (liver, kidneys and muscles) of subadults O. spilurus L. This study aimed also to study the effect of CPF on some biomarker parameters as well as examine histopathological changes on liver, kidneys and muscles in tilapia O. spilurus. Moreover, the protective role of vit C supplementation against the different biochemical and histopathological effects of Dursban 48 pesticide was tested for a period of 14 days.

الحارثي، عايض مريسي سالم

Pattern Recognition is of great importance in many real life applications, for example face recognition, fingerprint verification, disease categorization, prediction of survival rates for patients of specific disease, chromosome shape discrimination, optical character recognition, speech recognition, texture discrimination, among others. The discovery of knowledge hidden in data depends on pattern and is a step for accurate recognition. Any raw image data has many degrees of freedom and it is not possible to handle all those dimensions, to achieve an identification system, it is required that it gives result within a stipulated time. Therefore, such systems are designed to work in the domain of low dimension so that some results can be obtained when they are required. If the number of features, i.e. the pattern dimension, is more than the classifier will take more time to measure the intra-class and interclass distances. For example the distance in 𝑅1 is simple than that of 𝑅3. Dimensionality reduction helps to save time, cost and effort in the process of decision making in general and especially in pattern recognition. The process of dimension reduction is done under the condition that the quality of information is preserved. Statistical analysis methods are used as a guided approach to almost all real live problems and consequently in pattern recognition. Regression approaches are used to reduce the object is in the problem. Consequently, we get more accurate and less expensive models in many fields for example biological, physical, and social sciences, as well as in business and engineering. Linear models are useful in both the planning stages of research and analysis of the resulting data. One of the important and recent tools of pattern recognition is rough sets theory. We aim in this thesis to spot light on directions of rough sets theory applications in pattern recognition problems, and to explore in detail this role using case studies and examples. In our presentations of these examples, we focused on three stages of applying rough set approaches in pattern recognition problems, which are classification, attribute reduction and decision rules extractions. From the above discussion it became clear that pattern recognition is important for almost all real life problems and statistical methods with rough sets technologies are good tools for this line of study.

الحارثي، عايض مريسي سالم

Pattern Recognition is of great importance in many real life applications, for example face recognition, fingerprint verification, disease categorization, prediction of survival rates for patients of specific disease, chromosome shape discrimination, optical character recognition, speech recognition, texture discrimination, among others. The discovery of knowledge hidden in data depends on pattern and is a step for accurate recognition. Any raw image data has many degrees of freedom and it is not possible to handle all those dimensions, to achieve an identification system, it is required that it gives result within a stipulated time. Therefore, such systems are designed to work in the domain of low dimension so that some results can be obtained when they are required. If the number of features, i.e. the pattern dimension, is more than the classifier will take more time to measure the intra-class and interclass distances. For example the distance in 𝑅1 is simple than that of 𝑅3. Dimensionality reduction helps to save time, cost and effort in the process of decision making in general and especially in pattern recognition. The process of dimension reduction is done under the condition that the quality of information is preserved. Statistical analysis methods are used as a guided approach to almost all real live problems and consequently in pattern recognition. Regression approaches are used to reduce the object is in the problem. Consequently, we get more accurate and less expensive models in many fields for example biological, physical, and social sciences, as well as in business and engineering. Linear models are useful in both the planning stages of research and analysis of the resulting data. One of the important and recent tools of pattern recognition is rough sets theory. We aim in this thesis to spot light on directions of rough sets theory applications in pattern recognition problems, and to explore in detail this role using case studies and examples. In our presentations of these examples, we focused on three stages of applying rough set approaches in pattern recognition problems, which are classification, attribute reduction and decision rules extractions. From the above discussion it became clear that pattern recognition is important for almost all real life problems and statistical methods with rough sets technologies are good tools for this line of study. So, we chose the subject of our thesis: " Pattern Recognition and Rough Sets " This thesis consists of four chapters: Chapter 1: The purpose of this introductory chapter is to give an exploration for pattern recognition concepts, its importance and connections with rough set theory. Section 1.1 is devoted for the basics of pattern recognition. While section 1.2 aims to display applications and methods of pattern recognition. Also an account about rough sets applications in pattern recognition is given. Sections 1.3 is reserved for basic definitions and concepts used in this thesis. A brief account on information and entropy is given in section 1.4, while section 1.5 spots light on regression analysis. Sections 1.6 and 1.7 are concerned with thesis motivations and structure. Chapter 2: The main aim of this chapter is to give a comprehensive account on basic concepts of rough sets theory that play an important role in reduction of attributes, and extracting decision rules, which gives a generalized description of the knowledge contained in the data. Section 2.1 is an introduction, the target of section 2.2 is to give an account on basic concepts of rough sets theory, attributes reduction is discussed in section 2.3, the purpose of 2.4 is to compute some entropy measures of partitions in information systems, the goal of section 2.5 is to extract rules from an information system, finally section 2.6 concern about giving real life example for discover patterns (rules) in an information system for a biomedical experiment as typical. Chapter 3: The goal of this chapter is to explore some methods of reduction based on multivariate regression. Section 3.1 is an introduction, the purpose of section 3.2 is to give basic notions of comparison between regression methods. Finally section 3.3 is reserved for detail explanation for selecting best regression models and give examples. Chapter 4: This chapter proposes an approach based on similarity relation, which has the ability to deal with real-valued data whilst simultaneously retaining dataset semantics. More significantly, this chapter describes the underlying mechanism for this approach to utilize the information contained within the boundary region or region of uncertainty. The use of this information can result in the discovery of minimal feature subsets and improve classification accuracy. We give experimental evaluation which compares the suggested method with a number of existing feature selection techniques. Section 4.1 is an introduction, the target of section 4.2 is to give an account on reduction based on similarity, finally distance metric and mean lower approximation definitions are discussed in section 4.3, and all this supported by illustrative examples. Some results of chapter two have been presented in the scientific preparatory meeting for Fifth Scientific Conference in Riyadh.

القثامي، فيصل سعود

This research aimed to investigate the English language needs of Taif Airbase newly graduated cadets. The participants were 100 trainees who had been in the Airbase from one to three years after graduating from TSI. The data were collected through a questionnaire in order to seek answers for three research questions. 1) What are the English-language needs of the newly graduated cadets at Taif Air Base? 2) What is the cadets' impression of the TSI English language course? 3) How does the cadets‘ awareness of the importance of English in the workplace help them to identify their English-language needs? The data were analyzed through SPSS. The results revealed that the trainees‘ considered listening and speaking skills as the most needed skills on job compared to reading and writing skills. Moreover, the trainees' impression of their current English language course showed that it did not help them during training or job. Finally, the results indicated the trainees are not fully aware of the English importance for their job. Therefore, the researcher recommends designing an English language course based on learners' needs that meets the equivalent level of training and the job requirements. Furthermore, the researcher recommends elevating the cadets' awareness of their training programs and the critical role of English in their training and job through lectures, workshop and seminars.

الزهراني ، نورة محمد كميخ

القرشي ، وعد عبيد الله

In this work, two series of ternary alloyed Cd1-xCoxS QDs were deposited onto TiO2 electrode using successive ionic layer adsorption and reaction (SILAR) technique. The energy band gaps of the prepared samples were tuned by alloying at a certain size and controlling the QDs size at a constant molar ratio. The first series contains five samples of ternary alloyed Cd1-xCoxS QDs were prepared with different Co molar ratio (x = 0, 0.1, 0.2, 0.3, and 0.4) at constant QDs size. While the second one involves 10 samples of ternary alloyed Cd0.8Co0.2S QDs at different SILAR cycles. The morphology of the bare TiO2 electrodes and prepared ternary alloyed Cd1-xCoxS QDs/TiO2 photoanodes were scanned using the scanning electron microscopy (SEM) and the transmittance electron microscopy (TEM). SEM and TEM measurements prove the successful synthesis of the ternary alloyed QDs. X-ray diffraction (XRD) patterns analysis proves the success of the alloying processes and confirms the formation of the hexagonal crystalline structure of the ternary alloyed Cd1-xCoxS QDs. The optical properties of the prepared samples were characterized using the photoacoustic spectroscopy and Uv.vis spectroscopy which exhibits similar results. For the first samples series, the energy band gaps decreased as the Co molar ratio increase which attributed to the alloying. The second samples series, the energy band gaps exhibit the same behavior as SILAR cycles increase due to the quantum confinement effect. Vegard's low was used to determine the bowing constant for ternary alloyed Cd1-xCoxS QDs that found to be 0.748 eV. The CdS QDs size has been calculated using the effective mass approximation (EMA) and it is equal to 4 nm. The photovoltaic performance of the fabricated Cd1-xCoxS QDs sensitized solar cells has been studied. Compared to pure CdS QDSSC, Cd1-xCoxS QDSSCs shows better photovoltaic performance. Cd0.9Co0.1S QDSSC has been exhibit the best balance between the increased absorption and energy alignment of the QDs.

العتيبي، مشاعل مفرح دليم

This study is concerned with the improvement of the performance of dye-sensitized solar cells (DSCs) using polyethylene glycol (PEG) as a supporting medium with the dye. The obtained solar cells were characterized in terms of their structure, optical and photovoltaic properties. X-ray diffraction (XRD), scanning electron microscope (SEM) were utilized to investigate the structure and morphology of the obtained samples. Spectrophotometer was used to study the optical properties of the dyes used in this study. Finally, the I-V characteristics of the constructed cells were measured. The results have shown that there is no significant change in the structure upon the addition of PEG to the dye. On the other hand, the measured absorption showed no change of the absorption edge for all PEG concentrations with some changes in the absorption intensity. The photovoltaic effect was observed to change upon the addition of PEG to some extent. The efficiency of the obtained DSCs increased by about 44% (from 1.86% to 4.25%) with the increase of PEG concentration from 1 wt% to 8 wt%. This can be attributed to the help of the polymer as a polar material with the dye for generating more electrons and decreasing the recombination rate in the DSCs. However, addition of more PEG more than 8 wt% has shown a revers effect in the cell with a decrease in the power conversion efficiency. This was attributed to the decrease of the absorbance centers within the cell by the domination of the polymer, which could lead to a decrease in the electron density transferred to the anode and let the recombination to take place more effectively.

البقمي، مشاعل حباب سعد

In studying the effect of rate of flow of argon gas on the characterization and investigation of the optical properties of samarium oxide Sm2O3 thin fils, five thin films of Sm2O3 of thickness 200 nm were prepared under different rate of flow of the gas (1 sccm, 5 sccm, 7 sccm, 10 sccm and 20 sccm). X-ray diffraction pattern of the as-prepared five thin films showed two obvious peaks followed by amorphous background . The height of the two peaks is increasing with increasing the rate of flow indicating that the growth of the grain is increased. The grain size (D) was estimated using Scherrer formula. The estimated D was found to be in the range 10.5 to 12.5 μm. The scanning electron micrograph showed increasing the grain size with increasing the rate of flow . The spectral behavior of the transmittance T showed a sharp increase of the transmittance through the range of the applied photon wave length 288 – 365 nm with increasing the rate of flow. The intensity of the transmittance were 88.5%, 89.3%, 90.3%, 90.5% and 91.1% for the rates 1 sccm, 5 sccm, 7 sccm, 10 sccm, and 20 sccm, respectively, indicating that the transmittance increase slightly with increasing the rate of flow. The reflectance was found to behave as reverse of the behavior of the transmittance. It is seen that both the absorption coefficient and extinction coefficient decreased with increasing the photon wavelength through the range of wavelength 288 – 365 nm and seemed to be unaffected at wavelengths beyond this range which is consistent with the results of transmittance. The values of Urbach tail Eu was found to be 0.285, 0.205, 0.216, 0.229 and 0.198 eV indicating that it has a trend of decrease with increasing the rate of flow. The direct allowed optical energy gap Eg found to increase slightly in the range from 4.25 eV to 4.33 eV with increasing the rate of flow from 1 sccm to 20 sccm, respectively. The refractive index was found to behave as a normal dispersion and decreased with increasing the rate of flow. The variation of ε1 follows the same trend as the real part of refractive index whereas the variation of ε2 mainly follows the behavior of k which is related to the variation of α with photon energy. It was found that the dissipation factor decreases with increasing in the wavelength for all the considered films. The plasma frequency and the ratio of the carrier concentration to effective mass were found to decrease with increasing the rate of flow. Both of the single oscillator energy and dispersion energy were found to increase with increasing the rate of flow. Studying the optical conductivity it showed that it increases with increasing the rate of flow. In studying the effect of the pressure of the gas (20 psi, 40 psi, and 60 psi) on the optical properties of Sm2O3, it was found that the optical transmittance spectra show that the Sm2O3 thin films are highly transparent in nature as its transparency is about 95% where it increases slightly with increasing the pressure of the gas. The optical energy gap was found to have the values of 4.395 eV, 4.392 eV, and 4.315 eV for the gas pressure 20 psi, 40 psi and 60 psi, respectively, indicating a slight decrease with increasing the pressure or independent of the pressure of the gas more or less. On the mean time, Urbach tail was found to increase with increasing the pressure of the gas. The refractive index was found behave as normal dispersion in the visible rang of frequency and it decreases with increasing the pressure of the gas. Our results revealed that the single oscillator energy, dispersion energy, ratio of carrier concentration to effective mass are found to increase with increasing the pressure of the gas. The optical conductivity seems to be independent of the pressure of the gas; whereas it increases with increasing the energy of the incident photons.

السفياني ، تهاني عبد الرحمن

The present study was an attempt to evaluate the toxic effect of Acetaminophen alone and its combinations with either Silymarin or Nigella sativa extract. It is well known that Silymarin and Nigella sativa extract have been reported to be an effective antioxidant, therefore, the present study aimed to elucidate the possible ameliorative effect of Silymarin or Nigella sativa extract in reducing the toxicity of acetaminophen (paracetamol drug) when given to normal mice. This was done through studying the effects of acetaminophen on some liver, kidney function parameters, lipogram, male sex hormones as well as, reproductive performance and testosterone level, antioxidant enzyme activities, immunological parameters (TNF-α), as well as histopathological changes in vital organs (liver, Testis) beside TEM for liver sections of different groups. The use of supportive natural compounds like Nigella sativa extract, Silymarin and their combinations with acetaminophen was also evaluated in normal mice in order to get the best and safer treatment for hazardous side effects of acetaminophen.

الزايدي ، شروق محمد

Boronate affinity chromatography (BAC) is an important tool for specific capture and separation of cis-diol containing compounds such as glycoproteins, RNA, and carbohydrates. Only a few reports on monolithic column-based BAC have appeared. In this study, Boronate affinity monolith, poly(3-acrylamidophenylboronicacid-co-ethylene dimethacrylate) (AAPBA-co-EDMA), was prepared in glass tube by a one-step in-situ polymerisation procedure using a pre-polymerisation mixture consisting of functional monomer (3-acrylamidophenylboronicacid), cross-linker (ethylene dimethacrylate), porogenic solvent (methanol with poly ethylene glycol), and initiator (2,2-Dimethoxy-2-phenyle-acetophenone). A macroporous monolith was obtained after the systematic optimisation of preparation conditions. Then, the fabricated monolithic materials were characterized using different analytical techniques such as SEM/EDX analysis, and FT-IR spectroscopy. Finally, the obtained boronate monolith was used as a sorbent for selective enrichment of cis-diol containing compounds that was carbohydrates, nucleosides, and catechol.

الجعيد ، ريما عتيق

Two different biomimetic sensors were prepared by a modification of carbon paste electrode with two different iron (III) complexes] NTB-Fe(Cl)2[ Cl and ] Tp MeMe FeCl2[ . The modified electrochemical sensors have been characterized by electronic microscope (SEM). The electrochemical behavior of the obtained biomimetic sensors 1 and 2 has been studied by using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Square wave voltammetry has also been used for the direct electrochemical determination of acrylamide. The effect of different experimental parameters such as the type of supporting electrolyte and the solution pH has been investigated on the peak height of the prepared biomimetic sensors. The effect of acrylamide addition to the peak current signals for the obtained biomimetic sensors was examined. By increasing acrylamide concentration, the peak current signals for the obtained biomimetic sensors decreased. Using the optimum conditions, the prepared biomimetic sensors have been applied for the determination of acrylamide in different food samples collected from the supermarkets in Taif city, KSA.

الجودي ، هند سليمان

Rechargeable lithium-ion batteries (LIBs) are characterized with high specific energy, high efficiency and long life and hence are common power source for a wide variety of electronic devices, but the cost and toxicity of many cathode materials limit their scale-up. Worldwide research efforts are addressing this concern by transitioning from conventional Co- and Ni-based intercalation hosts towards the more environment friendly alternatives Fe- and Mn-based intercalation cathodes. In this work, maghemite which is iso-structural to spinel ferrites and essentially based on iron oxide which is a very cheap and naturally abundant compound undergoes structural modifications in order to achieve technologically relevant Li-ion storage capacities. Pentavalent (V5+) and hexavalent (Mo6+) doped maghemite nanoparticles were synthesized by sol-gel processing whereas the high valancy of the dopant cations provided a large population of defect sites inside the maghemite structure. These vacancies provide physical sites for Li-ion storage and hence they increase the electrochemical reactivity of the oxide, allowing to achieve high Li-ion capacities. Synchrotron radiation was used in recording high quality diffraction patterns of the prepared samples which were carefully refined using the Rietveld refinement method to obtain detailed structural and micro structural information and to reveal their relations to the concentrations of the dopant metal cations. The magnetic properties of the pure and doped maghemite samples were studied from the M-H loops measured using the method of vibrating sample magnetometer. The obtained saturation magnetization is used to study the distribution of the cations over the different crystal lattice sites and provided similar results to those previously obtained from the Rietveld refinements of the XRD patterns. Other magnetic properties were explained in the light of the cation distributions recovered from the structural studies with Synchrotron radiation diffraction and which matches with the corresponding distribution obtained from the analysis of the saturation magnetization. Other techniques like ATR-FTIR spectroscopy and HRTEM microscopy were exploited to support the results obtained from the XRD and magnetization measurements and to provide complementary information about the nature and composition of the studied maghemite materials. Finally, all the studied properties were correlated to the structure and micro structure of the prepared maghemite materials with various levels of doping with pentavalent and hexavalent metal cations. It has been shown that, increasing the doping level with both pentavalent and hexavalent cations increases the cation vacancy content than the natural level in pure maghemite and the vacancies on the octahedral sites are nearly twice that on the tetrahedral sites. Moreover, the study showed that Mo6+ show no site preference and distribute on both octahedral and tetrahedral sites indifferently; wherease V5+ strongly prefers the octahedral sites and is rarely found on octahedral ones. The current work is presented in five chapters. The first chapter introduce the concept of LIBs including their components and materials used in their production with focus on the materials used in intercalation cathodes. In the second chapter, the magnetism in ferrite materials is discussed with light thrown on the spinel ferrites. The main characterization technique of materials involved in this study is X-ray diffraction (XRD) is discussed with attention in the third chapter. The description of the methodologies and devices and other experimental techniques are detailed in chapter four. The obtained results are presented and discussed on the fifth chapter. Conclusions and recommendations are also appended to the work.

اليامي، أريج علي فارس

The objective of the present work is to investigate the optical properties of Se100-xTex (x=0, 5, 10, 15, 20, 25 and 35 in md %) films. A bulk chalcogenide glasses of Se100-xTex were fabricated first by quenching technique and used as a source to preparing amorphous thin films via thermal evaporation method. The optical constants of these films have been determined by variable angle spectroscopic ellipsometry (VASE) method using a photon energy range of 0.73 to 5.06 eV at room temperature. The spectrum of imaginary parts of dielectric for all films is characterized by several peaks one group of linear combination of oscillators were employed for the analysis of these spectrums. This group consist from one Tauc–Lorentz oscillators with two or three Gaussian oscillator (1TL+nG) .This group of models gives accurate fit to the experimental data. The effect of Te content on the refractive index, extension coefficient and models’ parameters (Lorentz oscillator amplitude, resonance energy, oscillator width, optical band gap, and Urbach energy) are discussed

عسيري ، أحلام محمد

الغريبي _ أفنان علي عبدالله

Objective: To investigate the prevalence of coxsackievirus and echovirus antibodies among neonates screened for thyroid stimulating hormone (TSH) of Taif Governorate. Methods: A total of 80 cord blood samples were included in this study for screening of thyroid stimulating hormone (TSH), coxsackievirus and echovirus antibodies by using ELISA test in neonates of Taif Governorate during the period from January 2018 till May 2018. Samples were classified according to TSH antibodies level into two main groups; diseased group (high TSH) and control group (normal TSH). Result: In the control group, of 40 cases, 10 (25%) samples were positive for coxsackievirus IgG and only 3 (8%) samples were positive for coxsackievirus IgM but without any evidence of clinical infection. All samples of the control group were negative for either echovirus IgG or IgM. In the diseased group, of 40 cases, only 10 (25%) samples were positive for coxsackievirus IgM but without any evidence of clinical infection and no samples were positive for coxsackievirus IgG. All samples of the diseased group were negative for either echovirus IgG or IgM. The study revealed a significant correlation between TSH status and coxsackievirus exposure. Conclusion: This study declared that no antibodies had been detected for either echovirus IgM or echovirus IgG. The prevalence of coxsackievirus (12.5% for Cox IgG and 16.25% for Cox IgM) is very low among children neonates of Taif governorate when compared to the global prevalence rate.