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Crystallization Kinetics of Melt-Blended Low-Density Phthalic Anhydride with a Low-Tg Tin-Phosphate

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Open Journal of Polymer Chemistry 2014年第3期4卷 38-46页

作者： Laila M. al-harbi Chemistry Department Faculty of Science King Abdulaziz University Jeddah Saudi Arabia

Polyamide prepared by the reaction of ethylene diamine with different ratios between 1,6-glyconic acid and phthalic anhydride. The differential scanning calorimetry (DSC) is used to study the nonisothermal and isothermal crystallization of low density polyamides in phosphate glass (Pglass)-polymer hybrid blends. The % crystallinity decreased as the Pglass volume increased. The half-life (t1/2) for crystallization decreased as the propagation rate constant rose for both the polymer matrices with increasing Pglass concentrations. The results show that the Pglass is improved nucleating agent for formation of the Pglass-polymer hybrids up to 35% Pglass and the energy necessary to break decreased. The stability of the reaction of ethylene diamine with phthalic anhydride and glyconic acid was qualitatively investigated using molecular orbital calculations.

关键词： Polyamides Crystallinity Phosphate Glass-Polymer Hybrids DSC and Kinetics

Numerical Methods for Solving Logarithmic Nonlinear Schrödinger’s Equation

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Journal of Applied Mathematics and Physics 2022年第12期10卷 3635-3648页

作者： Anees al-harbi Waleed al-Hamdan Luwai Wazzan Department of Mathematics King Abdulaziz University Jeddah Saudi Arabia

In this study, we will construct numerical techniques for tackling the logarithmic Schrödinger’s nonlinear equation utilizing the explicit scheme and the Crank-Nicolson scheme of the finite difference method. These schemes will be subjected to accuracy and stability tests before being used. Efficacy and robustness of the techniques under consideration will be demonstrated using an exact solution, one-Gausson, as well as conserved quantities. Interaction of two-soliton will be conducted. The numerical findings revealed, the interplay behavior is flexible.

关键词： Explicit Scheme Implicit Scheme Exact Solutions Bounded Domain Stability One Soliton Soliton Interaction Gaussons

Exact Traveling Wave Solutions to Phi-4 Equation and Joseph-Egri (TRLW) Equation and Calogro-Degasperis (CD) Equation by Modified (G'/G²)-Expansion Method

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Journal of Applied Mathematics and Physics 2023年第7期11卷 2103-2120页

作者： Maha al-harbi Waleed al-Hamdan Luwai Wazzan Department of Mathematics King Abdulaziz University Jeddah Saudi Arabia

In this study, we will introduce the modified (G'/G2)-expansion method to explore some of the exact traveling wave solutions of some nonlinear partial differential equations namely, Phi-4 equation, Joseph-Egri (TRLW) equation, and Calogro-Degasperis (CD) equation. As a result, we have obtained solutions for the equations expressed in terms of trigonometric, hyperbolic and rational functions. Moreover, some selected solutions are plotted using some specific values for the parameters.

关键词： Exact Solutions Modified (G'/G2)-Expansion Method Phi-4 Equation Joseph-Egri (TRLW) Equation Calogro-Degasperis (CD) Equation

Blood Consumption in Placental Abnormalities

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Open Journal of Obstetrics and Gynecology 2022年第10期12卷 1092-1101页

作者： Mufareh Asiri Salem al Suwaidan Nawal al harbi Abuobeida Ahmed Reem alanazi Razan al harbi Najla al Ajmi Maternity Hospital King Saud Medical City Riyadh KSA Research Center King Saud Medical City Riyadh KSA

Introduction: Hemorrhage is one of the most common causes of maternal morbidity and mortality. This study was conducted to investigate how much abnormal placentation can affect blood bank capacity and to measure the burden on the blood bank caused by excessive use of blood and blood products. Methodology: This is a retrospective study conducted at King Saud Medical City Maternity Hospital in Riyadh, Kingdom of Saudi Arabia, from January 2019-September 2020. It includes 170 cases diagnosed with abnormal placentation (low-lying placenta or placenta previa, accreta, increta, or percreta). The primary purpose was to measure consumption of blood and blood products in cases of placental abnormalities and to investigate how much this affects blood bank capacity. A secondary aim was to report rates of admission to the ICU and maternal mortality. Results: This study included 170 women with placental abnormalities. Placental previa had occurred in 96 cases, followed by placenta accreta in 46 cases, placenta increta in 13 cases, placenta percreta in 8 cases, and low-lying placenta in 7 cases. Most patients (93) were treated with a Bakri balloon to prevent hemorrhage, but 38 patients had a hysterectomy. The average estimation of blood loss was 2210 ml, with no maternal mortality. An average of 3.39 units of packed red blood cells (PRBC) with a maximum of 20 units, 2.12 units of fresh frozen plasma (FFP) with a maximum of 20 units, and 0.7 units of packed platelets (PP) with maximum of 12 units consumed per patient. Eighty-seven patients (51.2%) were admitted to the ICU and 83 others (48.8%) were admitted to the high dependency unit. Conclusion: Blood and blood product volumes had a linear relationship with the severity of placental abnormalities and estimated blood loss. Therefore, blood bank services should be available to save mothers’ life.

关键词： Placenta Previa Placenta Accreta Spectrum (PAS) Hemorrhage Maternal Mortality Hysterectomy

Predictors of Glycemic Control among Patients with Type 2 Diabetes in Najran Armed Forces Hospital: A Pilot Study

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Journal of Diabetes Mellitus 2014年第2期4卷 141-147页

作者： Imed Harrabi Fawaz al harbi Saad al Ghamdi Department of Family and Community Medicine Najran Armed Forces Hospital Najran KSA Department of Internal Medicine Najran Armed Forces Hospital Najran KSA

Background: Diabetes mellitus is a serious condition with potentially devastating complications that affects all age groups worldwide. The purposes of this study are to describe the glycemic control levels and to determine the associated factors of poor glycemiccontrol among type 2 diabetes patients followed in Najran Armed Forces Hospital. Methods:We conducted a retrospective analysis of administrative data from adult patients with diabetes type 2 followed in NAFH clinics. To be included in the pilot study, patients needed to meet the following criteria: 1) Be identified as having diabetes type 2 using algorithms employed by disease management oasis program;2) Be at least aged 18;3) Be male or female;4) Have Fasting Plasma Glucose (FPG) and HbA1c measured at least twice during the last year. Both univariate and multivariate approaches of logistic regression were applied to determine factors associated with poor glycemic control. Results: Data from a total of 100 patients were analyzed. There were 22% of patients that achieved glycemic control. The risk factors associated with poor glycemic control were being female, age al cholesterol. Conclusion: The findings of this study showed that diabetic control is suboptimal. This study provides factors that predict poor glycemic control. With this information, sub-groups with high risk of disease morbidity were identified. Barriers that prevent these patients from meeting their goals must be explored to improve health outcomes.

关键词： Glycemic Control Diabetes Type 2 Adults

Spatial Configuration of Traditional Dwellings in Riyadh al-Khabra Traditional Town, Saudi Arabia

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World Journal of Engineering and Technology 2022年第2期10卷 272-291页

作者： Mamdouh Mohammed al-harbi Nashwan al-Ansi Mohammed alrubayan Department of Architecture College of Architecture and Planning Qassim University Buraydah Saudi Arabia

Traditional buildings, particularly residential dwellings, are spatio-temporal reflections of the society and culture in which they were originally sited. Understanding the nature of this built heritage thus fosters interpretation of previous generations’ experiences in these older settlements, all of which can thus be described as products of several different cultural dimensions. Qassim province, which sits in the central province of the Kingdom of Saudi Arabia, is distinguished by having retained various traditional towns and villages, including multiple dwellings representing important eras in the past. However, due to the local population’s abandonment of these traditional towns and movement to new urban areas, and related failures in conservation and restoration, some of these towns have lost many of their unique characteristics, especially with regard to their dwellings. This research thus attempts to interpret the relationships between the spatial configuration of traditional dwellings in Saudi Arabia and their socio-cultural principles and values, focusing on decoding their interior spatial constants and genotypes. The study proposes the use of space syntax theory, represented by the justified plan graph method, as an appropriate socio-spatial methodology for such work, targeting the traditional town of Riyadh al-Khabra in Qassim province as a case study area, with eight dwellings built between 1900 and 1940 used as examples. Interpretation of analysis results enabled defining spatial constants digitally in these traditional dwellings through the benefit of syntactic analysis techniques, and the main findings of this research reveal the significance of various social and cultural factors and customs among inhabitants with regard to determining the spatial form and properties of traditional dwellings in towns such as Riyadh al-Khabra.

关键词： Traditional Dwellings Socio-Cultural Space Syntax Spatial Configuration Justified Plan Graphs Riyadh al-Khabra Town

Finite Difference Implicit Schemes to Coupled Two-Dimension Reaction Diffusion System

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Journal of Applied Mathematics and Physics 2018年第4期6卷 737-753页

作者： Shahid Hasnain Muhammad Saqib Nawaf al-harbi Department of Mathematics Numerical Analysis Division King Abdulaziz University Jeddah KSA Department of Mathematics Air University Islamabad Pakistan

In this research article, two finite difference implicit numerical schemes are described to approximate the numerical solution of the two-dimension modified reaction diffusion Fisher’s system which exists in coupled form. Finite difference implicit schemes show unconditionally stable and second-order accurate nature of computational algorithm also the validation and comparison of analytical solution, are done through the examples having known analytical solution. It is found that the numerical schemes are in excellent agreement with the analytical solution. We found, second-implicit scheme is much faster than the first with good rate of convergence also we used NVIDA devices to accelerate the computations and efficiency of the algorithm. Numerical results show our proposed schemes with use of HPC (High performance computing) are very efficient and reliable.

关键词： Crank Nicolson Taylor’s Series Richardson Extrapolation and alternating Direction Implicit

Nutritional, Chemical and Organoleptical Characteristics of Low-Calorie Fruit Nectars Incorporating Stevioside as a Natural Sweetener

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Food and Nutrition Sciences 2017年第1期8卷 126-140页

作者： Hassan Barakat Abdulaziz al-Furaydi Abdulelah al-harbi ali al-Shedookhi Food Science and Human Nutrition Department College of Agriculture and Veterinary Medicine Qassim University Buraidah Kingdom of Saudi Arabia Food Technology Department Faculty of Agriculture Benha University Moshtohor Egypt

The study is aiming at preparation of low-calorie fruit nectars for diabetes and weight maintaining approaches as well as consumer satisfaction. Therefore, twenty low-calorie fruit-based formulated nectars were prepared mainly from orange, pomegranate, guava and mango pulps which sweetened with sucrose or sucrose— replaced at 25%, 50%, 75% and 100% using stevioside. Primitively, the yield of fresh fruits had been calculated. Consequently, nutritional, chemical and organoleptical characteristics of prepared fruit nectars have been determined. Results indicated that total solids content was in range of 5.57% - 13.20%, 9.90% - 14.37%, 8.25% - 13.27% and 8.25% - 16.50% for orange, pomegranate, guava and mango nectars, respectively. Dependently, caloric value resulted 21.57 to 51.08, 38.31 to 55.62, 31.93 to 51.37 and 31.93 to 63.86 kcal 100 g-1 fw for orange, pomegranate, guava and mango nectars, respectively. Total phenols content [TPC, mg GAE 100 g-1 dw] ranged from 665.12 to 747.41, 1180.42 to 1319.47, 742.54 to 848.27 and 418.01 to 472.42 for orange, pomegranate, guava and mango nectars, respectively. The antioxidant capacity by DPPH method [μmol TE g-1 dw] ranged from (20.79 to 26.51), (47.13 to 56.56), (60.68 to 69.25) and (8.39 to 13.32) for orange, pomegranate, guava and mango nectars, respectively. Total carotenoids [mg 100 g-1 dw] were the highest in mango nectars ranged from (102.99 to 110.52) in mango nectar with 100% sugar and mango nectar with 100% stevioside, respectively. Anthocyanins content recorded 6.14 mg 100 g-1 dw in pomegranate nectar with 100% sugar, while increased to be 9.01 mg 00 g-1 dw in pomegranate nectar with 100% stevioside. Ascorbic acid [mg 100 g fw] ranged from 23.41 to 27.53, 15.73 to 18.32, 25.72 to 30.87 and 18.07 to 20.98 for orange, pomegranate, guava and mango nectars, respectively. The results of organoleptical attributes showed no effect of sugar substituting by stevioside on color, odor and mouth feel. The most dramatic effect

关键词： Low-Calorie Nectar Chemical Nutritional Organoleptical Characteristics

Preliminary Comparative Physiological and Biochemical Study of Five Different Goat Breeds Inhabiting Saudi Arabia

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Natural Resources 2012年第4期3卷 206-212页

作者： Mohammed Salem al-harbi Sayed Amin Mohamed Amer Department of Biology Faculty of Science Taif University Taif Saudi Arabia Department of Biology Faculty of Science Taif University Taif Saudi Arabia Department of Zoology Faculty of Science Cairo University Giza Egypt

Three arbitrary chosen enzymes were examined by native-polyacrylamide gel electrophoresis to investigate physiological and genetic variations among five different goat breeds inhabiting Saudi Arabia. The goat breeds were Pakistani, Tihami, Syrian, Masri and Aardi while the investigated enzymes were alkaline phosphatase (alP), malate dehydrogenase (Mdh) and malic enzyme (ME). Six polymorphic loci with six monomeric alleles have been recorded in all studied breeds. The second locus of ME was characteristic of Syrian breed where it showed dimeric alleles. The similarity matrix that has been calculated according to the number of sharing bands indicated that these breeds have been divided into two groups: Pakistani and Tihami as one group while the other three breeds clustered in another group. The activity of the metabolic enzymes (Mdh and ME) showed concordance with the constructed relationship where the percentage amounts of these enzymes showed significant variations between the two groups more than that occurred within each group. Mdh was expressed in the second group more than in the first while ME showed, nearly, equal expression in the different breeds. Both genetic and physiological results agreed in clustering the studied breeds into Pakistani and Tihami in one group and the other three breeds in another group. This division was based on a few gene loci and a few sampling size and it needs to be supported by collecting more genetic data and more sampling size in a further molecular study.

关键词： Goat Breeds Electrophoresis Isoenzymes Physiology Saudi Arabia