الهلالي، هيفاء فهد محمد

The Central venous catheters understudy were number 30 from Neonatal Intensive Care Unit (NICUs), each CVCs Cannula samples were cut into four parts (A, B, C and D), each about (15-16) millimeter (mm), part A; parts (B, C and D "Hup"). The bacterial biofilm were confirmed by Electron Microscope in part (A) samples. The bacterial growth were in (D, B and C); (25.6, 17.8 and 14.4%); Gram-positive revealed 86.8% and Gram-negative13.2%. The most common of Bacterial biofilm; Staphylococcus (hominis, epidermidis, haemolyticus, capitis and warneri). Enterococcus faecium, Bacillus species, pumilus, Escherichia coli, Pseudomonas aeruginosa, and Candid albicans. The pathogenicity had done by antibiotics sensitivity test those conclusion-cleared factors could form the bacterial biofilm and access to bloodstream causing neonatal septicemia. The pre-mature neonates with low birth weight and some diseased, catheters types and hygienic measures, all help in formation of catheter biofilm. Isolation of bacteria from Cannula was human normal flora and soil, or poor hygienic measures that was dangerous to have bacteria antibiotic resistant. That recommended caring of pre-mature neonates; diseased might affected, do not use the long-time catheter, modification use recent catheter. Must create good hygienic measures healthy hospitals or medical center. keywords: The Central venous catheters؛ biofilm؛ septicemia

الثبيتي ، هيا محمد مسفر

Apple Mosaic Virus detected in some naturally infected apple, plum and Rosa damascena (Taif Rose) trees. ApMV found to woody spread in stone fruit and Rosa damascena (Taif Rose) growing in different locations Taif Governorate (Al-Shafa, Al-Hada and Qurwa .The ApMV was transmitted mechanically containing some material to several herbaceous plants but transmitted by grafting easily to different host plants . Studied the host range and symptoms of the ApMV isolates (AP,PL,RO) were tested which included seventeen hosts belonging to ten families. DAS-ELSIA and Dot Blot Immunoassay used detection ApMV that all three isolates for ApMV. The Electron microscopic examination of ultrathin sections obtained from leaves of apple plants (Malus domestica.cv Balady), examination indicated the cytological changes of ApMV an apple leaf tissue which were observed in the cells of mesophyll ultrathin section. RT-PCR based assay was applied for detection of the nucleic acid of Apple Mosaic Virus (ApMV-AP) in infected apple plants. The specific primers were used to amplify the full coat protein gene of ApM-AP. Amplified fragments at 817 bp. Pairwise comparisons of the nucleotide sequences gave identities ranging from 97% to 89% compare the molecular variation of the Apple Mosaic Virus- kingdom of Saudi Arabia isolate with that of other ApMV world isolates. ApMV Taif-KSA has ~ 97% similarity with India , Czech , Franc and Russia while ~ 95% with Germany. The ApMV was isolated in the gene bank under (KY488189) for the first time and compare the molecular variation of the ApMV- kingdom of Saudi Arabia isolate with other ApMV world isolates. Production of Apple Mosaic Virus –free pear and Rosa damascena (Taif Rose) tree plants by chemotherapy Virazole® Ribavirin(10,20,30)% mg/l . Indicated that in at concentration (20%) was effective in eliminating of ApMV (35%) in pear and (40%) in Rosa damascena (Taif Rose) but the higher concentrations of Ribavirin (30%) were phytotoxic for treated shoots of pear and Rosa damascena (Taif Rose).

مغربي ، آمال محمد عبد القادر

Prunus necrotic ringspot virus (PNRSV) was isolated from naturally rose plants grown in differant locations in AL-Shafa, in Taif Governorate of Saudi Arabia. Virus isolate was propagated in Rosa damascena. The virus isolate was identified as PNRSV on basis of host range, virus stability, modes of transmission, serological and molecular biology studies. Study of host range which included different plant species belonging to ten different families revealed that reaction of different hosts differed according to tested virus. Data concerning modes of transmission of the isolated virus showed that PNRSV was mechanically and pollen transmitted. The validity of ELISA regents was determined by DBIA on nitrocellulose membrane where positive reaction was obtained. The RT-PCR products amplified from total RNA of Rosa damascena plants infected with PNRSV by specific primer PNRSV1 and PNRSV2. A cDNA fragment of 681 bp. The phylogenetic homology tree based on multiple sequence alignments showed that the PNRSV-RD /Taif-KSA )KY488188( has ~89% similarity with Canada (JQ005051), and Pch12 (jn416776) and from New- Zeland (EF3). Rosa damascena plants free of prunus necrotic ring spot virus PNRSV were produced by chemotherapy treatments, which known as virus inhibitors, as well as, eliminates of viruses present in the tissue. These components as Ribavirin (Virazole) gave 0.0, 10.0, 13.3% virus free plants determined using (ELISA) when Ribavirin added to the medium in the level of 10, 20, 30 mg/ L respectively whereas the infection of untreated plants (control) reached to 100%.

الثقفي ، منى مصلح حامد

Much research has shown that information focus and contrastive focus (i.e., aspects of information structure) is encoded prosodically in many languages including few of Arabic dialects that have been studied. However, recent studies show that there are languages that do not encode focus prosodically, and hence, information focus and contrastive focus are not represented in their prosodic system. This thesis presents experiment work on the prosodic encoding of information focus and contrastive focus in Thaqafi Arabic Dialect (i.e., an Arabic dialect spoken in Thaqafi area in the Hijazi region in the Kingdom of Saudi Arabia). To my knowledge, this study is the first study that aims to investigate whether information focus and contrastive focus are prosodically encoded compared with each other and with their neutral-focus counterparts in declarative sentences in Thaqafi Arabic Dialect (TQD, henceforth). It aims to provide acoustic analyses of the data, attempting to find out whether and how information focus and contrastive are acoustically encoded. Sixteen native speakers (10 females and 6 males) of TQD recorded short declarative sentences with “narrow” information focus and “narrow” contrastive focus at different locations or without any “narrow” focus. Detailed F0 analyses show that focus is realized by expanding the excursion size of the on-focus stressed syllables, compressing the excursion size of the post-focus syllables, and compressing the stressed syllables of the pre-focus region (if any). These findings demonstrate that in terms of prosodic focus, Thaqafi dialect is similar to the prosodic focus in Urban Hijazi Arabic investigated by Alzaidi (2014); however, it is different from the prosodic focus in Egyptian Arabic (Hellmuth, 2006).

اللحياني ، إلهام حميد عبد الحميد

Recent studies show a strong relationship between prosody and focus (i.e., as an aspect of information structure) in some languages. Therefore, prosodic information is represented in linguistic frameworks adopted to account for facts existing in languages including English (Lambrecht, 1996). Recent research, however, has revealed that focus is not prosodically encoded, and hence its prosodic role is not crucial in some languages, such as Hausa (Hartmann and Zimmermann, 2007). Studies investigating the role of focus in the prosody of Makkan Arabic being rare, this study presents an experimental investigation into whether focus is prosodically encoded in Makkan Arabic. Fifteen native speakers of Makkan Arabic were recruited for the experiment. The participants read test materials in question-answer paradigms to evoke three different types of focus: broad focus, "narrow" information focus, and "narrow" contrastive focus. The narrow information focus and the narrow contrastive focus were placed in three different sentential positions: initial, penultimate, and final. Only excursion size of the fundamental frequency of the pre-/post-/on-focus region has been analyzed. Results show that only the excursion size of the information focus and contrastive focus are more expanded than that of their broad-focus counterparts. The type of focus, either information or contrastive, are not prosodically , distinguished. This leads to conclude that focus is prosodically encoded in Makkan Arabic however, the types of focus are not. As for the post-focus region, results show that focus has no prosodic effect on post-focus region when the focused word is sentence-initial. However, when the focused word is sentence-penultimate, only the excursion size of the post-focus region occun-ing after the contrastive-focus words are more compressed than of their counterparts in the broad-focus utterances. Pre-focus region is not prosodically affected when the word in focus is sentence-penultimate, however, when the word in focus is sentence-final, the excursion size of pre-focus region occurring before information focus and contrastive focus are more expanded than of their broad focus utterance. These results show that prosodic effects of focus in Makkah Arabic are different from prosodic effects found in Hijazi Arabic, Egyptian, and Lebanese Arabic .

الفعر، محمد عبدالله

The protective action of salicylic acid (SA) and ascorbic acid (ASC) on linuron herbicide treated cucumber plant was studied by investigating leaf morphological appearance, leaf physiological activities and leaf cell ultrastructure. As an observable injury symptoms, spraying of linuron induced chlorosis and necroses of young and mature leaves that was recognized by eye observation and decreasing in chlorophylls and carotenoid contents. Linuron (150 μM) increased soluble carbohydrate, whereas soluble protein and total carbohydrate contents were decreased. Linuron significantly increased total amino acids, proline, and total phenolic compounds and malondialdehyde (MDA). Total antioxidant activities (TAA), peroxidase and ascorbate oxidase activities of cucumber leaves were gradually increased with increasing linuron suggested that stress generated by the herbicide treatments. Spraying of 50 μM SA or 50 μM ASC one day before 150 μM of linuron treated plants increased chlorophylls, total protein and ascorbate oxidase activity in comparison with those of 150 μM of linuron treated plants. In contrast, water content, carotenoid, proline, MDA, total phenolic compounds, TAA and peroxidase activity decreased in comparison with those of 150 μM linuron treated plants. The organization of thylakoid membranes of chloroplasts affected by 150 μM of linuron. Many vesicles and depletion of starch gains were occurred within chloroplasts. SA or ASC application partially reduced the disorganization of grana stacks of linuron treated cucumber. These results suggested that SA and ASC could be used as antioxidants and a stabilizer of membrane integrity to improve cucumber resistance against linuron herbicide .

الغامدي، سعاد حسن صالح

The present thesis was designed to utilize the pregnant mice as an in vivo model to compare the potential of date fruit extract in prevention the developmental toxicity of Ochratoxin A (OTA). Also, to determine the protective effects of date fruit extract on the genotoxicity, teratogenicity, biochemical and histopathological effects of OTA on the fetus and dam mice throughout the pregnancy period (at the end of organogenesis period, 13th day, and at the end of the pregnancy, day 19th). Five treatment groups included, control group, solvent group, group treated with OTA at 2 mg/ kg body wt. during organogenesis period (from 6th -12th day of pregnancy). The 4th group were treated orally with date extract at 8.75 mg/ kg body wt. throughout pregnancy (from day 0 – 18th day) and group five which was treated as group three and group four together. The results of experiments have proved effectiveness of Date palm extract to potentiate the toxicity induced by Ochratoxin A in the dam and fetus mice. The results showed significant changes caused by Ochratoxin A at the chromosomal aberration study in bone marrow of dam and fetus cells on 13th day of gestation. The teratological results also showed morphological changes in the fetus. In addition, structural abnormalities were observed in the skeletal system, weight reduction and high absorption level of fetuses in the OTA-treated groups compared to the control. Histological studies of hepatic and renal tissues showed some effectives in the both investigated tissues, which supported with biochemical results that show disturbance in the selected enzymes level. The results emerged for the groups treated with Date extract before injection of Ochratoxin A were proved effectiveness the Date extract as prevention of all previous negative effects and reduce their occurrence by high significant level.

المالكي ، حصة متعب

In this thesis we study pseudo structures for some types of alge- bra. In particular, we study BF -algebra and consider its extensions; pseudo BF -algebra and pseudo BF ∗-algebra. Then we study the algebraic properties of pseudo BF -algebra and pseudo BF ∗-algebra and find the relation between pseudo BF -algebra and pseudo BF ∗- algebra with some other classes of algebras (e.g., pseudo BCK- algebra, right-pseudo MV -algebra and right-pseudo BL-algebra). Moreover, we show that pseudo BF -algebra and pseudo BF ∗-algebra are a bounded lattice-ordered.

الزهراني، عائشة حسين منصور

Herein, we reported the efficient synthesis of new azoles as bio-functional analogs, employing the easily obtainable N-acetyl-3,5-diphenyl-4,5-dihydro-1H-pyrazole-1-carbothioamide (149), 3-(3,5-diphenyl-4,5-dihydro-1H-pyrazol-1-yl)-5-methyl-1H-1,2,4-triazole-1-carbothioamide (151) and 1-(3-(dimethylamino)acryloyl)-3-(4,5-dihydro-3,5-diphenyl pyrazol-1-yl)-5-methyl-1H-1,2,4-triazole (170), as a versatile precursors in moderate yields. Then, the reactivity of the terminal carbothioamide, thiazole and acetyl tags, was exploited in a series of manipulations encompassing cyclocondensation for the modular synthesis of new pharmacophoric motif probes. The structures of the newly synthesized vi compounds were elucidated based on their IR, 1H NMR, 13C NMR mass spectral and elemental analysis. Finally, some selected newly synthesized compounds were screened for their in vitro antibacterial activity against two gram-positive species namely Staphylococcus aureus RCMB 0100010 (SA) and Bacillus subtilis RCMB 010067 (BS) and two gram-negative species Pseudomonas aeuroginosa RCMB 010043 (PA) and Escherichia coli RCMB 010052 (EC). They were also tested for their in vitro antifungal activity against two fungal species namely; Aspergillus fumigatus RCMB 02568 (AF) and Candida albicans RCMB 05036 (CA). The preliminary bioassay results indicate that, the majority of the tested compounds exhibited significant anti-microbial activity against the tested microorganisms. Compounds 160, 159, 166, 178, 170, 151 and 150 were found to be the most potent against the tested microorganisms with MIC ≤ (12.25 μg/ mL), in decreasing order .that conjugates bearing thiazole moiety as well as, those with N-substituted electron-withdrawing groups, exhibited higher potency than the rest of other compounds. Keywords: Pyrazoles, N-heterocycles, azoles, N-acetylcarbothioamide, anti-microbial activity.

الزهراني، صالح مطر سعيد

It has been approximately 50 years since researchers first began exposing polymeric materials to ionizing radiation, and reporting the occurrence of cross-linking and other useful effects. Today, a substantial commercial industry is in place based on processing of polymers with radiation. Innovation in this field has by no means ended; important new products made possible through radiation technology continue to enter the marketplace, and exciting new innovations in the application of radiation to macromolecular materials are under exploration at research institutions around the world. In this work we care both the successful radiation processing technologies now in use, and new material radiation technologies that are emerging from research laboratories. An objective of this work is to provide workers , and composite scientists in general, with an overview on the status of progress toward commercial products and technologies in the broad area of radiation processing. More recently, radiation curing of polymer/ceramic composites has begun to come into use. The material prepared by this process has significantly better stability, high-performance and high-temperature applications than polymer only. This technology has been commercialized. More recently, this approach has been extended to the production of Polystyrene/ferrite composite. This material is being explored for use in aggressive environments such as nuclear power plants, high tech electronic devices, integrated capacitors and aerospace applications. The present work is to study gamma radiation effect during composite preparation on the physical, structural, morphology, thermal and electrical properties. The Ni0.6Cd0.4Fe2-xSmxO4 was prepared using a conventional sintering ceramic process. Ferrite product and Styrene was mixed and achieve polymerization process by gamma irradiation at 50 kGy. The conclusions derived from study characteristics of PS/ Ni0.6Cd0.4SmxFe2-xO4 composite are summarized as follow : The diffraction peaks were shifted to different positions of Bragg's angle as the Sm content increases. X-ray patterns show single spinel phase for all investigated samples. Stability of the crystalline structure and no phase transition are found due to irradiation. The bulk density decreases, X-ray density increase and porosity increase with increasing Sm contents before and after irradiation. The lattice parameter increases after irradiation and became nonlinear dependence with increasing of Sm content. The theoritical lattice parameter ath. has values near aex at low concentration of Sm , but are slightly different at higher concentration of Sm. The tetrahedral radii rA remains constant with Sm concentration but octahedral radii rB increases before and after irradiation. Value of the shortest distance between B site and O2- ions (q) and the shortest distance between A site and the O2- ions ( p) decrease after irradiation.The distortion of the lattice increases by increasing Sm content.No significant changes after irradiation in the values of oxygen positional parameter (u)and deviation constant (δ).The average crystallite size tm increase with increasing of Sm content before irradiation and decrease with increasing of Sm content after irradiation but the crystallite size generally increase after irradiation at the same Sm concentration. The grain size shows increasing trend with gamma irradiation . The PS nearly coat the grains and so their boundaries become faint and not sharp.The gamma radiation transfer Fe3+ to Fe2+ due to its ionizing effect .The Fe 2+ occupy octahedral site and the stretching vibration of its bond with oxygen (Fe 2+- O2- ) gives absorption at about 462 Cm-1 near octahedral absorption at 392 Cm-1 .The PS/ Ni0.6Cd0.4SmxFe2-xO4 composite become thermally more stable than pure polystyrene. Introducing ferrite reduces the rate of decomposition. The activation energy of conduction Eσ has a small values in the range of hopping conduction mechanism .The Sm content increases the Curie point. Resistivity of PS/ferrite composite increase by about 109 order of magnitude than the ferrite. The electrical resistivity has three regions with increasing temperature, below Tg, above Tg, belongs to ferrite conduction mechanism at high temperature.

المالكي، حنان موسى عبيد

Hydrogen gas is now considered as a source of efficient, clean, and renewable energy capable of addressing global and environmental challenges. It is therefore one of the most likely future fuels to diminish our dependence on fossil fuels. In industry, steam methane reformer method is widely used to generate hydrogen, carbon monoxide, and natural gas. However, the main disadvantage of this method, besides its requirements of high-energy (heat) input, is the production of CO2 gas as a by-product. CO2-free hydrogen can be produced at room temperature via water electrolysis. For this process to be efficient, an electro catalyst capable of reducing the over potential of the hydrogen evolution reaction (HER), the reductive half reaction of the water splitting process, and accelerating its kinetics should be used. Platinum-based materials are the most stable and efficient electro catalysts for the HER. However, these materials are highly expensive and therefore increase the cost of water electrolyzes. The objective here is to fabricate new, highly efficient, stable, and inexpensive electro catalysts for the HER for CO2-free H2 generation . The goal of this work was also to improve the performance of TiO2 nanomaterials by increasing their optical and electrical activities by shifting the onset of the response from the UV to the visible-light region. Among the several ways to achieve this goal, doping TiO2 nanomaterials with other elements (e.g. metals) was selected to narrow the band gap and enhance the optical and electrical properties of TiO2 nanomaterials. In this work, we have prepared RE-doped TiO2 nano-catalysts, characterized them and studied their properties, and the electrical ones in particular. To achieve this purpose, a new and facile synthesis method of RE- doped titanium dioxide (RE-TiO2) nanoparticles (NPs) at different atomic concentrations of RE is presented. This novel approach allows one to produce titanium dioxide nanoparticles owing to a modified solvothermal process that makes use of Titanium(IV) . The structure and morphology of the TiO2 nanoparticles have been characterized by using Fourier transform infrared spectroscopy (FTIR), thermo gravimetric-differential thermal analysis (TGA-DTA), X-ray diffraction (XRD), X-ray fluorescence (XRF), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDX) and high-resolution transmission electron microscopy (HRTEM). Afterthen, the obtained TiO2 nanoparticles-doped Gadolinium and neodymium as effective catalysts for efficient electrochemical hydrogen production. The proposed study of controlling doping will be important in tailoring the material for deliver better performance. The experimental work conducted here revealed promising results for improving the performance of the TiO2 nanomaterial by doping it with RE where the optical activity was enhanced and shifted to the visible region causing an appreciable increase in its effectiveness for electrocatalytic applications. Keywords: Titanium dioxide; RE-doped TiO2 nanoparticle; Band gap; Electrochemical Water Splitting; Hydrogen generation.

المالكي ، حنان موسى عبيد

Hydrogen gas is now considered as a source of efficient, clean, and renewable energy capable of addressing global and environmental challenges. It is therefore one of the most likely future fuels to diminish our dependence on fossil fuels. In industry, steam methane reformer method is widely used to generate hydrogen, carbon monoxide, and natural gas. However, the main disadvantage of this method, besides its requirements of high-energy (heat) input, is the production of CO₂ gas as a by- product. CO₂-free hydrogen can be produced at room temperature via water electrolysis. For this process to be efficient, an electro catalyst capable of reducing the over potential of the hydrogen evolution reaction (HER), the reductive half reaction of the water splitting process, and accelerating its kinetics should be used. Platinum- based materials are the most stable and efficient electro catalysts for the HER. However, these materials are highly expensive and therefore increase the cost of water electrolyzes. The objective here is to fabricate new, highly efficient, stable, and inexpensive electro catalysts for the HER for CO₂-free H₂ generation . The goal of this work was also to improve the performance of TiO₂ nanomaterials by increasing their optical and electrical activities by shifting the onset of the response from the UV to the visible-light region. Among the several ways to achieve this goal, doping TiO₂ nanomaterials with other elements (e.g. metals) was selected to narrow the band gap and enhance the optical and electrical properties of TiO₂nanomaterials. In this work, we have prepared RE-doped TiO₂ nano-catalysts, characterized them and studied their properties, and the electrical ones in particular. To achieve this purpose, a new and facile synthesis method of RE- doped titanium dioxide (RE-TiO₂) nanoparticles (NPs) at different atomic concentrations of RE is presented. This novel approach allows one to produce titanium dioxide nanoparticles owing to a modified solvothermal process that makes use of Titanium(IV) . The structure and morphology of the TiO₂ nanoparticles have been characterized by using Fourier transform infrared spectroscopy (FTIR), thermo gravimetric- differential thermal analysis (TGA-DTA), X-ray diffraction (XRD), X-ray fluorescence (XRF), transmission electron microscopy (TEM), energy dispersive X- ray spectrometry (EDX) and high-resolution transmission electron microscopy (HRTEM). Afterthen, the obtained TiO₂ nanoparticles-doped Gadolinium and neodymium as effective catalysts for efficient electrochemical hydrogen production. The proposed study of controlling doping will be important in tailoring the material for deliver better performance. The experimental work conducted here revealed promising results for improving the performance of the TiO₂ nanomaterial by doping it with RE where the optical activity was enhanced and shifted to the visible region causing an appreciable increase in its effectiveness for electrocatalytic applications.

الوعيل، نجوى عمر سعيد

Aims of the study Most of the previous studies clarified that the effect of vit C against the oxidative /antioxidant changes of MSG has not been investigated before. Therefore, the present study was conducted to determine the protective role of vitamin C against the toxicity of MSG. The body weights, hematological parameters, liver functions biomarker, kidney functions, balance of oxidative stress and antioxidant have been evaluated with /without vit C. This study had four main points to clarify 1) Determination of some blood serum contents. 2) Evaluation of hepatic damage biomarkers enzymes by measuring the activities of lactic dehydrogenase (LDH), alanine aminotransferase (ALT) and total proteins content as well as the levels of cholesterol and high density lipoprotein cholesterol were determined. 3) Evaluation of renal damage biomarkers by measuring the levels of uric acid and creatinine. 4) Investigation of oxidative damage/antioxidant biomarkers such as lipid peroxidation level, free radical scavenger enzymes (superoxide dismutase and glutathione-S-transferase) and levels of non-enzymatic antioxidant (reduced glutathione, ferric reducing antioxidant power and ascorbic acid).

العمري، ايمان ظافر

Tremendously fast, the English language is becoming a key instrument in education and technology. Hence, mastering the language is considered one of the requirements of the present time. Undoubtedly, various variables play a vital role in the English language learning process. As evidence by previous research, learning autonomy and motivation toward learning English are viewed as key factors in successful English language learning outcomes. This study was conducted to investigate the effectiveness of learning autonomy and language learning motivation on the English achievement of Saudi EFL learners. The researcher addressed the following five questions: Firstly, what is the level of perceived learning autonomy for Taif university students? Secondly, what is the level of language learning motivation for Taif university students? Thirdly, are there any differences between males and females in motivation, autonomy and English achievement? Fourthly, Can learning autonomy affect EFL students` English achievement at Taif University? Fifthly, Can motivation affect EFL students` English achievement at Taif University? The sample consisted of 130 Saudi male and 153 female first year university–level students enrolled in a mandatory course of English as a foreign language in the Science department of Taif University, Saudi Arabia. The data was collected quantitatively by a language learning motivation questionnaire (Saheb, 2014) and learning autonomy questionnaire (Orawiwatnakul and Wichadee, 2017). Additionally, learners' scores on an English test were collected to measure their English achievement. The data were analyzed using descriptive analysis, mean standard scores, standard deviation, t-test and regression analysis. Results indicated that learners reported a moderate level of learning autonomy but a high level of language learning motivation. Gender differences exist in learning autonomy, motivation and English achievement, all in favor of female learners. In addition, the findings revealed that language learning motivation and autonomy do affect the participants' English achievement.

الحارثي ، بشرى حاظر عبدالله

In this thesis, we study the complex lag synchronization (CLS) of chaotic complex nonlinear systems with uncertain parameters. We introduce an application in secure communications in light of the results of CLS. Also, we propose a novel kind of complex synchronization; we call this type "modified complex phase synchronization" (MCPS). We make an application in secure communications based on the results of MCPS. We introduce and analyze a new hyperchaotic complex detuned laser system. We study the dynamics of this system. We combine the two previous types of complex synchronization and introduce a new definition of complex synchronization. We call this type "modified complex phase synchronization with time lag" (MCPSTL). We employ the results of MCPSTL to achieve a simple application in secure communication. The results of this thesis are consistent with the Kingdom’s vision (2030), especially on cybersecurity, given the recent increase in cyber attacks. Various types of synchronization have been applied to secure communications, and this supports our goals and aspirations to provide a secure communication and ensure the confidentiality of information transfer.