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- ItemANALYSIS AND DEVELOPMENT OF A FUTURE MASTER PLAN FOR THE ELECTRICAL POWER SYSTEM IN PALESTINE(An-Najah National University, 2025-11-20) Salameh,OsamaGiven the growing energy demands in Palestine and the significant issues faced by the energy sector, including power supply challenges, especially in recent years. It is necessary to formulate a comprehensive master plan for the energy sector. The suggested strategy aims to address these challenges and ensure a safe, dependable, and efficient energy supply in the future. The plan will focus on creating a strategic framework for improving and developing Palestine's energy infrastructure over the next few decades. The energy sector in Palestine encounters a range of challenges, including outdated and deteriorating infrastructure, the absence of an efficient energy transmission system, and limited energy resources. Additionally, geopolitical fluctuations, rapid population and urban growth, industrial development, an increasing number of electric vehicles, and a heavy reliance on Israel as the primary source of energy further exacerbate the situation. Palestine gets 86% of its electricity needs from Israel and the rest from Jordan and Egypt, supplemented by local power generation through a PV solar system, with 5.3% from total energy consumption in Palestine in 2023. It is important to point out that the current war on Gaza destroyed the infrastructure completely, which created more obstacles and challenges. Recent reports indicate that the ongoing Israeli war of extermination on Gaza since 2023 has had disastrous effects on the electricity sector infrastructure, destroying about 80% of the networks, while initial estimates of the damage amounted to $700 million. The plan aims to develop a reliable, durable, and environmentally friendly energy system by modernizing existing networks, establishing a 161 KV transmission system that encompasses all Palestinian territories, and ensuring the provision of electricity safely and reliably, improving energy efficiency by reducing the total losses in the system. Investigate the potential for building new substations in all districts to meet power demands and increase the share of energy production in Palestine's total energy consumption. Additionally, assess the grid's capacity to accommodate increased power demands without technical issues. Utilize renewable energy sources in the energy mix, and enhance energy self-sufficiency by reducing dependence on imported energy from Israel. In summary, the plan, which is expected to be completed by 2035, will address current issues and create investment opportunities in Palestine while also establishing a foundation for future energy needs. It sets a strategic framework for achieving energy independence, improving infrastructure, promoting sustainable development, and contributing to building an integrated power system for gradual disengagement from Israel. Thus, the plan contributes to the transition of the State of Palestine to a safer and more environmentally sustainable energy model.
- ItemINVESTIGATION OF THE BEHAVIOR OF UNREINFORCED MASONRY CONCRETE BEARING WALLS USING MICRO MODELING APPROACH(An-Najah National University, 2025-10-14) Abuhasan, HadeelUnreinforced masonry concrete bearing walls (UMCBWs) were commonly used in Palestinian buildings between the 1950s and 1970s, as well as in historical architecture in Palestine and the Middle East. Although these buildings are no longer constructed today, many of them remain in service for residential and commercial purposes. Due to limited research, their seismic behavior is not well understood and requires further investigation. This study develops a numerical micro model using ABAQUS software to examine the in-plane lateral behavior of UMCBWs. The research began by defining the wall system and using a published experimental study as a reference case study for developing and validating the micro model. The model was validated by comparing its lateral load-displacement response and damage pattern with the experimental result. The validated modeling approach was applied to the parametric study. Four main parameters were investigated, wall length, concrete thickness, axial pressure, and opening ratio, to evaluate their effects on lateral behavior. Nonlinear static general analyses were performed on fifty-six UMCBW models in ABAQUS to generate pushover curves. The influence of these parameters on lateral strength, stiffness, ductility, and failure mode was analyzed and confirmed by the micro model results. The results showed that increasing wall length and thickness leads to higher strength and stiffness but reduces ductility. Increasing axial pressure significantly enhances lateral strength. The pressure levels were expressed as percentages of the concrete compressive strength (f^' c). Below 15% of f'c, the effect of axial pressure on stiffness is negligible, whereas above 35% of f^' c, it significantly reduces stiffness. In addition, increasing axial pressure dramatically decreases ductility. The presence of an opening reduces strength, stiffness, and ductility, although at low axial pressures, for certain opening ratios, it can improve ductility. The results obtained from the micro models were categorized based on axial pressure levels and subsequently used to derive equations for estimating bilinear pushover curves. These simplified equations provide a practical tool for representing the seismic response of UMCBWs and can support future assessment and rehabilitation strategies for existing buildings.
- Itemمدى وعي طلبة الصفّين الحادي عشر والثاني عشر في فلسطين لموضوع الكوارث وفهم مخاطرها (دراسة حالة في مدارس محافظة رام الله والبيرة)(جامعة النجاح الوطنية, 2025-09-03) Barghouthi, Thaerإن وعي المجتمع الفلسطيني، وخاصة فئة الشباب والطلبة فيه، هو أساس قدرته على الصمود في مواجهة الكوارث والحد من مخاطرها، وإن دراسة وعي هذه الفئة الكبيرة والمؤثرة، ومعرفة نقاط قوتها وضعفها لهي الخطوة الأولى لرفع مستوى الوعي لديها ضمن خطة وطنية لتعزيز قدرة المجتمع الفلسطيني على مواجهة الكوارث والحد من مخاطرها. تهدف هذه الدراسة، الأولى من نوعها على هذه الفئة، إلى استكشاف وعي الطلبة الثانويين في فلسطين حول الأخطار والكوارث وفهم مخاطرها، ومدى توفر مهارات السلامة العامة لديهم، واستشراف ميولهم للمشاركة والتطوع في المجتمع لمواجهة الكوارث. صُمّمت دراسة الحالة هذه كبحث وصفي لفحص انعكاس ظاهرة الكوارث في وعي الطلبة (مجتمع الدراسة) في محافظة رام الله والبيرة التي اختيرت لأهميتها الكبيرة، نظراً لتنوعها السكاني وشمولها لمختلف فئات المجتمع الفلسطيني، مما يسمح بتعميم النتائج على طلبة فلسطين عموماً. وشملت عينة الدراسة مختلف مكونات مجتمع الدراسة، واعتُمدت الاستبانة المحكّمة بنموذجيها الإلكتروني والورقي أداة لجمع البيانات، وعززت نسبة الاستجابة المرتفعة مصداقية النتائج. أكدت نتائج الدراسة الفرضيات الأساسية التي انطلقت منها وهي: محدودية وعي الطلبة في موضوع الكوارث، ونظرتهم المحدودة تجاه مواجهتها كعملية استجابة طارئة لا كإدارة متكاملة لمخاطرها، وعدم جاهزية المجتمع المحلي لمواجهتها. وأظهر الطلبة في بعض المحاور مستوى جيداً من الوعي مع بعض الضعف والخلط في المفاهيم والتعريفات، ورغم إدراكهم لأهمية "توعية الجمهور"، إلا أنهم لم يعتبروه الإجراء الأهم في مواجهة الكوارث. وقيّم معظم الطلبة بدرجة عالية من الخطورة الأخطار المباشرة الموجودة في بيئتهم القريبة، وخاصة الاحتلال. وبرزت الإنترنت ووسائل الإعلام كمصادر رئيسية لمعرفة الطلبة حول الكوارث، وكانت المواقع الإلكترونية ومنصة "إنستاغرام" الأكثر استخداماً من قبلهم. وكشفت الدراسة كفاية نسبة الطلبة الذين يملكون مهارات السلامة العامة كالإطفاء والاسعاف، ونقص الخدمات الصحية في المدارس مما يزيد من المخاطر على هذه الفئة عند وقوع الحوادث والكوارث، وأبدى معظم الطلبة استعدادهم للتطوع في مواجهة الكوارث. وأظهرت الدراسة افتقاد الشعور بالأمان لدى معظم الطلبة (خاصة الذكور) في مدارسهم، ومناطق سكناهم. وعبر غالبيتهم عن عدم رضاهم عن تغطية المنهاج الدراسي لموضوع الكوارث ومخاطرها. إن تحقيق أهداف الدراسة يتطلب معالجة الضعف في وعي الطلبة، بتعزيز معرفتهم للمفاهيم المتعلقة بالكوارث ومخاطرها وآثارها، ووضع خطة وطنية لتوعية الجمهور بالأدوار المنوطة به في مواجهة الكوارث، وذلك باستخدام القنوات المناسبة لهم، لرفع مستوى صمودهم وتعزيز مهارات السلامة والأمان لديهم في البيت والمدرسة، وتسخير دافعيتهم العالية للتطوع في مواجهة الكوارث، وتعزيز دور المنهاج الدراسي في ذلك.
- ItemMICROBIOLOGICAL PROFILE AND ANTIMICROBIAL RESISTANCE AMONG DIABETIC FOOT INFECTIONS: A CROSS-SECTIONAL STUDY FROM PALESTINE(An-Najah National University, 2025-10-02) Arjan, Amanee SolemanAbstract Background: Diabetic foot ulcers are serious complications that can increase morbidity and mortality among diabetic patients. Little is known about the different strains of bacteria that can be isolated from patients with diabetic foot ulcers who receive care in governmental hospitals in the north of the West Bank of Palestine. This study was conducted to evaluate the microbiological characteristics and bacterial resistance patterns of patients admitted to one of the main referral governmental hospitals in the north of the West Bank of Palestine. Methods: The study was conducted using a retrospective cross-sectional design. The study was conducted at Rafidia Surgical Hospital, which is one of the main referral governmental hospitals in the north of the West Bank of Palestine. The data were collected from patient records, laboratory reports, and sensitivity/resistance test findings. All referred patients to the hospital during January 2022 to December 2022 were included in the study. Results: In this study, files for 118 patients with diabetic foot infections who had culture results were identified, reviewed, and analyzed. Of these patients, 53 (44.9%) were admitted to the hospital for a heel pressure ulcer, and 46 (39.0%) were admitted for an infected toe. Of the 118 patients admitted, 4 cultures showed no growth, and 114 showed bacterial growth. Of the isolates, 67 (58.8%) were Gram-negative bacteria and 47 (41.2%) were Gram-positive bacteria. The detailed culture results are shown in Table 3. Of the 47 Gram-positive isolates, 1 (2.1%) was ESBL, and 18 (38.3%) were MRSA. None (0.0%) of the isolated Gram-positive strains were MDR. Of the 6 Enterococcus spp., 1 (16.7%) was ESBL. Of the 18 isolated Staphylococcus aureus, 11 (61.1%) were MRSA. On the other hand, 23 (31.3%) of the isolated Gram-negative bacteria were ESBL, and 7 (10.4%) were MDR. Of the 16 isolated Escherichia coli, 11 (68.8%) were ESBL. All 8 (100%) isolated Klebsiella pneumoniae were ESBL. Similarly, all 4 (100.0%) isolated Acinetobacter baumannii and both (100.0%) isolated Citrobacter spp. were MDR. Additionally, 1 (20.0%) of the 5 isolated Morganella morganii was ESBL, and 1 (20.0%) was MDR. Of the 2 isolated Enterobacter cloacae, 1 (50.0%) was ESBL. Among the Gram-negative isolates, 9 (13.4%) were CRE. Of the patients, 74 (62.7%) had moderately sized ulcers, and 31 (26.3%) had severely sized ulcers. The majority of the patients had osteomyelitis (62.7%) and gangrene (74.6%). Initially, the vast majority of patients (97.5%) received debridement. Of the patients, 41 (34.7%) received minor amputations, and 31 (26.3%) received major amputations. Patients who had neuropathy, were previously hospitalized in the last 90 days, had heart failure, hyperlipidemia, chronic kidney disease, malignancy, abnormally low HDL, osteomyelitis, gangrene, major amputations, and those who died had significantly higher rates of moderately and severely sized ulcers. Patients with low income, neuropathy, heart failure, chronic kidney disease, malignancy, osteomyelitis, gangrene, major amputation, and larger-sized ulcers were more likely to die. Conclusions: The epidemiology, microbiology, and clinical outcomes of diabetic foot infections in patients admitted to one of the main referral centers in Palestine were described. The findings showed that Gram-negative bacteria were the predominant pathogens isolated. A considerable proportion of the isolated bacteria was shown to be resistant to many antibiotics. The findings also showed that MRSA was prevalent among the Gram-positive isolates. This indicates that treating some diabetic foot infections could be highly challenging. The findings of this study showed that poor glycemic control, the presence of other diabetes-related complications, and the presence of other comorbidities correlated with disease severity and adverse outcomes. Decision-makers and healthcare providers should develop and implement antimicrobial stewardship programs and evidence-based treatment guidelines to optimize the outcomes of patients with diabetic foot infections.
- ItemBIOBASED POLURETHANE FOAM PREPARATION WITH CATIONIC AND ANAIOIC RECEPTORS: DESIGN SYNTHESIS AND APPLICATION IN WASTEWATER PURIFICATION(An-Najah National University, 2025-09-30) Abu Leil, BahiaHeavy metal contamination in drinking water can harm organs and is a major cause of cancer and other serious conditions. Metal- and dye-binding polymers are effective in adsorbing and removing dyes and toxic metals from water. This study aims to synthesize a range of bio-foam polymers featuring diverse functional groups and polymer architectures, with the objective of evaluating their efficacy in removing dyes and heavy metals from contaminated water. Furthermore, a protocol was established for the extraction of these metals and dyes from solution. Bio-foam polymers were prepared, and cellulose was used as a bio-based polymer. Four polymers with several coordination sites for metal ions and dye adsorption from sewage were synthesized. Efficiency of adsorption was studied for Cd(II) and methylene blue dye was investigated as a function of adsorbent dose, concentration temperature, pH, and time. The optimum parameters with highest adsorption efficiency were determined. The polymer on foam form were prepared from cellulose using a method composed of several steps. The first step involves cellulose oxidation to cellulose aldehyde using 2,2,6,6-Tetramethylpiperidine 1-oxyl (TEMPO)/sodium hypochlorite in alkaline medium to produced cellulose aldehyde which was reacted with cysteine to produce cellulose functionalized with amin acid functional group (Cell-Cs-H) which then crosslinked with 1,6-hexamethylenedisiocayante and 1,4-pehenylenediisocyanate to produce cellulose based foam with amino acid functionality Cell-Cs-H and Cell-CS-P, respectively. The produce form then converted to zwitterionic polymers by reacting them with 1,3-proane sultone to produce Cell-Cs-H-S and Cell-Cs-P-S, respectively. All polymers were analyzed by FTIR, SEM, and TGA. All polymers showed excellent efficiency toward methylene blue and methyl orange dyes in addition to metal ions. The diversity and frequency of the coordination was the reason for the high extraction efficiency of the foams, it was almost quantitative for both dyes and metal ions, especially for foams with zwitterionic functionality. The thermodynamic analysis results (The Gibbs energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0) were calculated) supported the spontaneous adsorption efficiency of the polymer at room temperature. The kinetic study revealed that the metal ion and dye adsorption by polymers was pseudo-second order and followed the Langmuir isotherm model.