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- ItemTHE IMPACT OF EMPLOYEES' PERFORMANCE AS A MEDIATOR VARIABLE ON THE RELATIONSHIP BETWEEN TOTAL QUALITY MANAGEMENT PRACTICES AND CONSTRUCTION PROJECTS PERFORMANCE IN PALESTINE(An-Najah National University, 2025-05-07) Ahqar, AysarThe construction sector plays a significant role in economic growth, particularly in emerging regions like Palestine. However, construction project performance often faces challenges related to quality, efficiency, and employee engagement. These issues raise concerns about how to improve outcomes for both employees and projects in a sustainable manner. This study addressed the impact of total quality management practices on the performance of construction projects in the Palestinian construction sector. It also investigated the mediating role of employee performance in the relationship between total quality management practices and project performance. Based on the literature, four hypotheses were formulated. A descriptive analytical research method was used. Quantitative data for this study were collected in the field and online through questionnaires from 100 construction companies. The data collected from the questionnaires were analyzed using the partial least squares (PLS-SEM) method. The results showed a significant positive impact of total quality management practices on both projects and employees’ performance in contracting and consulting companies. Additionally, employee performance positively influenced the performance of construction projects. The study also demonstrated the mediating role of employee performance in the relationship between total quality management practices and construction project performance. The study contributes to closing the gap in the research literature by presenting and testing a proposed model. It also raises awareness among managers and employees in the Palestinian construction sector about the importance of integrating quality management practices into company policies with the aim of improving the performance of both employees and projects, as it provided empirical evidence for that. The thesis recommends that companies should seek to adopt total quality management practices more comprehensively, and pay greater attention to employee development and performance, working to involve and empower them in decisions related to quality. The study also outlines key limitations and recommendations for future studies.
- ItemTHE IMPACT OF ENTERPRISE RESOURCE PLANNING (ERP) IMPLEMENTATION ON SUSTAINABILITY PERFORMANCE IN HEALTHCARE AND THE MEDIATOR EFFECT OF JCI(An-Najah National University, 2025-04-17) Abu Al Haj, Ebaa MaherThe integration of Enterprise Resource Planning (ERP) systems in healthcare organizations presents a significant opportunity to enhance operational efficiency and improve accreditation outcomes. However, the relationship between ERP implementation and sustainability performance, particularly through the lens of Joint Commission International (JCI) accreditation, remains underexplored. This study addresses this gap by investigating how various factors, such as clinical error reduction, operational productivity, data analytics, and resource optimization, mediate the effects of JCI accreditation on the relationship between ERP implementation and sustainability performance. To conduct this research, a sample of 53 administrative staff from two hospitals in Nablus and Jerusalem were surveyed for this research. This approach differs from most prior research, where subjects were normally professionals with long experience in management and technology fields. In this context, the research will employ a more diverse sample to enrich the understanding of ERP systems’ capabilities to support sustainability objectives in healthcare organizations. Data were analyzed using descriptive statistics to quantify and summarize key variables within the population. Statistical software was employed to conduct correlation and regression analyses, providing a robust framework for interpreting the relationships among variables, like SPSS , Smart PLS . The key findings indicate a statistically significant positive relationship between implementing ERP and getting JCI certification. This supports the hypothesis that ERP increases the likelihood of meeting JCI standards. However, contrary to the existing literature, our study found no significant influence of either ERP or JCI on sustainable performance. This suggests that organizations have problems aligning their ERP systems with sustainable objectives because of fragmented processes and scant integration into strategic goals. Based on these findings, it is recommended that healthcare organizations align their ERP systems with sustainability goals. This can be done by promoting better coordination between business units on strategic targets and encouraging staff to take part in sustainability ventures. Future studies need to follow up on these dynamics in more detail to discover how they can best influence overall healthcare practice towards sustainability.
- ItemEFFECTS OF DIFFERENT FORMS OF DATE PALM (ELAEIS QUINEENSIS JACQ.) LEAVES ON THE PERFORMANCE AND SOME PRODUCTIVE AND REPRODUCTIVE TRAITS OF CROSSBRED EWES(An-Najah National University, 2025-02-27) Shakhshir, Ali Abdo AliAbstract This research comprised two experiments. The first experiment aimed to examine how various preparations of date palm leaves (DPL), including chopped, ensiled, and alkali-treated forms, affected the performance and reproductive efficiency of crossbred ewe lambs. A total of twenty female ewes were used at age of 6-7 months were fed the DPL at 15% of their diets for a period of 6 weeks. DPL was replaced similar percent of wheat hay in the control diet. The ewes were split into four experimental groups, with each group consisting of five ewes, and each ewe treated as a separate replicate. Ewes were fed as the following: Group 1 (G1) served as the control, consisting of 70% concentrate and 30% wheat straw, for the experimental groups G2 to G4, various forms of date palm leaves (DPL) were incorporated into the diets to replace half of the wheat straw. A digestion trial was conducted after 28 days of the feeding trial. Ewes were exposed to rams were conception rates and other reproductive traits were recorded. Prior to conception ewes were examined for blood parameters and a digestibility trial was performed. The results indicated that form of DPL had no significant effects on all study parameters. The second experiment consisting of 28 cross bred lactating ewes were used to examine the DPL forms on milk yield and quality, blood parameters and nutrient digestibility. The ewes were organized into four experimental groups, with each group containing seven ewes, and each ewe regarded as an individual replicate. Ewes were fed similar diets as in experiment 1. Results of experiment 2 indicated the lack of effects of forms of DPL on the tested parameters. In experiments 1 and 2 the economic efficiency of feeding DPL was examined. In conclusion, incorporating date palm leaves (DPL), whether in their raw or treated forms (ensiled or alkali-treated), offers significant benefits by lowering feed costs and contributing to environmental protection. However, further research is needed to determine the optimal treatment and inclusion levels for these diets.
- ItemEXPLORING THE STRUCTURAL, MECHANICAL, ELECTRONIC, MAGNETIC, OPTICAL AND THERMOELECTRIC PROPERTIES OF QUATERNARY HEUSLER ALLOYS FEMNSCGA, FEMNSCAL AND FEMNCRGE(An-Najah National University, 2025-04-27) Masri, HasanThis dissertation presents a comprehensive analysis of the structural, electronic, magnetic, optical, and thermoelectric properties of three quaternary Heusler compounds: FeMnCrGe (Iron-Manganese-Chromium-Germanium), FeMnScAl (Iron Manganese-Scandium-Aluminum), and FeMnScGa (Iron-Manganese-Scandium-Gallium), using first-principles theoretical frameworks. This research relies on the density functional theory (DFT). The calculations use the Perdew–Burke–Ernzerhof (GGA-PBE) functional. This approach uses a generalized gradient approximation. It ensures precise electronic structure analysis. Additionally, it uses the modified Becke-Johnson (mBJ) functional. These approaches help to evaluate the material's potential applications in spintronics and energy conversion devices. All three compounds have a face-centered cubic structure with adherence to the Fm-3m space group. A negative formation energy characterizes their stable configurations. This confirms their stability. Moreover, they comply with mechanical stability conditions. FeMnCrGe (Type 1 structure), FeMnScAl, and FeMnScGa (Type 2 structures) all meet mechanical stability requirements and exhibit structural stability through a hybrid ionic-covalent bonding framework. The electronic structure analysis depicts strong half-metallic behavior for all compounds studied, with 100% spin polarization. The FeMnCrGe compound has a spin-down bandgap value calculated as 0.974 eV with a modified Becke-Johnson potential, compared with a 0.1574 eV bandgap for FeMnScAl and 0.442 eV for FeMnScGa. As per the Slater-Pauling rule, magnetic moments have been calculated. The FeMnCrGe compound illustrates a magnetic moment value per formula unit as 1.00 μB, with FeMnScAl and FeMnScGa having magnetic moments of 3.00 μB each. Such a fluctuation is attributed to strong ferromagnetic behavior, which is substantiated through strong magnetic interactions from manganese. Investigation of the thermoelectric properties reveals high efficiency in energy conversion. The material FeMnScAl has a peak value for ZT of 0.689 at 150 K, and FeMnCrGe has a value of 0.42 at 500 K. Also, the optical properties of all three compounds demonstrate high ultraviolet absorption, with FeMnScGa having absorption coefficients above 180 × 10⁴/cm. Additionally, all materials exhibit a high refractive index, and large interband transitions are present. These characteristics suggest excellent potential for optoelectronic devices. Their impact could be significant in advanced applications. These materials offer significant potential. They could advance spintronic, thermoelectric, and optoelectronic technologies. These materials exhibit half-metallicity, stable magnetism, and strong thermoelectric properties. This unique combination creates new opportunities. It helps to address challenges in conventional electronics and energy harvesting. The theoretical framework as a whole presents a solid foundation for future empirical research, as well as for real applications of these flexible materials for constructing novel technological advancements.
- ItemDESIGN, SYNTHESIS, BIOACTIVITY AND MOLECULAR DOCKING OF IMIDAZOLONE DERIVATIVES HAVING HYDROPHILIC AND LIPOPHILIC FUNCTIONALITIES(An-Najah National University, 2025-05-07) Fares, Oswa MarwanThe currently used chemotherapies showed negative side effects that can lead to permanent damage to human organs. Therefore, finding an effective anticancer therapy with minimum side effects is considered a major challenge for scientists. In this work, two new series of imidazolones were prepared, one containing phenyl group (3a-g) and the other containing thiophene group (5a-g). Both of these imidazolones were combined with different substituents including lipophilic and hydrophilic moieties. The synthesis was performed via condensation cyclization of vanillin-based oxazolones with various amines. The anticancer activity of the synthesized imidazolones was analyzed against four different cancer cell lines: liver cancer cells (HepG2), cervical adenocarcinoma cells (HeLa), colon cancer cells (CaCo-2) and breast cancer cells (MCF-7). Among the prepared imidazolones, it was found that imidazolone 3f with dodecyl chain exhibited the highest anticancer activity with IC50 value of 65.26 ± 3.2 µM against HepG2 and 20.02 ± 3.5 µM against MCF-7. Imidazolone 3d with amino alkyl group displayed an IC50 value of 36.57 ± 4.1 µM against the Hela cell and 24.68 ± 3.8 µM against the CaCo-2 cell line. Imidazolone 5g with thiophene and pyridyl group showed the highest efficiency among all tested derivatives with an IC50 value of 18.44 ± 2.3 µM and 5.96 ± 2.3 µM against Hela and CaCo-2 cell lines, respectively. Imidazolone 5b with chlorophenyl moiety displayed an IC50 value of 2.18 ± 0.7 µM and 5.51 ± 1.1 µM against HepG2 and Hela cell lines, respectively. Computational tools were also used to evaluate the pharmacokinetics, and the antitumor potential of imidazolone molecules with the highest activities through ADME analysis and molecular docking. ADME properties, estimated by the Swiss ADME server, emphasize favorable drug-likeness under Lipinski’s guidelines, with molecular weights ranging from 357.43 (5d) to 468.65 g/mol (5f). Molecules 3g, 3f, and 5f show optimal hydrogen bonding, moderate bioavailability (0.55), and synthetic accessibility scores from 3.78 to 4.76. Docking studies with proteins 4MAN and 1HNJ highlight strong interactions for 3g, 3f, and 5f, with molecule 3g showing the best binding for 4MAN (-52.13 kcal/mol) and 5f for 1HNJ (-38.63 kcal/mol). These results recognize 3g and 5f imidazolones as promising candidates for targeted cancer therapy. In addition, antibacterial activity was studied for the prepared oxazolones. It was noticed that oxazolone 8 containing 2-thiophenyl moiety was the most potent to stop the bacterial growth of all types of bacteria, even the most resistant Staphylococcus aureus with MIC of 500 µg/mL. A combination of these oxazolones with commercial antibiotics can provide a synergetic effect to inhibit the bacterial growth at lower MIC values.