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توطين علم النفس في الكويت | أ. د. عثمان الخضر
No full textالمدخل يقوم على ربط توطين علم النفس بالاولويات التنموية في الكويت بحيث توظف الدراسات النفسية في دعم خطط التنمية الوطنية والبرامج الحكومية متوسطة المدى مع التركيزعلى الجوانب التطبيقية لا النظرية فقط
Sustainable Groundwater Treatment: Enhancing NF and UF Membrane Efficiency with Agro-Waste-Derived Crystalline Nanocellulose
No full textQatar is located on the eastern edge of the Arabian Peninsula and is characterized by an arid climate with minimal rainfall. In the absence of surface water resources, groundwater represents the country’s primary natural freshwater supply, with approximately 92% of extracted groundwater utilized for agricultural purposes. Prolonged overextraction has contributed to the deterioration of groundwater quality, with elevated concentrations of trace elements such as molybdenum (Mo), boron (B), and lithium (Li) reported in several wells across Qatar. Although membrane filtration is widely applied for groundwater treatment, its performance is often hindered by membrane fouling, underscoring the need for surface modification strategies to enhance treatment efficiency.
This study evaluated the physicochemical quality of groundwater collected from ten farms in Qatar and employed spatial interpolation analysis using ArcGIS to assess contaminant distribution. The results revealed that Mo, B, and Li, along with other water quality parameters, exceeded guideline limits established by the World Health Organization (WHO), Gulf Standardization Organization (GSO), Qatar drinking water standards, and United States Environmental Protection Agency (US-EPA) health advisories. To address these challenges in a sustainable manner, crystalline nanocellulose (CNC) was extracted from date-pit agro-waste and utilized to modify ultrafiltration (UF) and nanofiltration (NF) membranes.
X-ray diffraction (XRD) analysis confirmed the crystalline structure of CNC, with characteristic peaks at 15.5° and 22.5° and a crystallinity index of 39.5%. Fourier transform infrared spectroscopy (FTIR) verified the presence of functional groups, while atomic force microscopy (AFM) and scanning electron microscopy (SEM) analyses confirmed successful CNC coating on the membrane surfaces. The CNC-modified NF membrane (NF-CNC) exhibited a reduction in surface roughness from 37.8 to 19.8 nm, whereas the CNC-modified UF membrane (UF-CNC) showed an increase in roughness (35.56 to 44.50 nm) accompanied by improved hydrophilicity following surface modification.
Filtration experiments conducted at operating pressures of 5 bar for NF and 2 bar for UF demonstrated that UF-CNC outperformed all other membranes, achieving greater than 90% rejection of B, Li, and Mo. These results were statistically validated using Tukey’s post-hoc test. The dominant removal mechanisms were attributed to Donnan exclusion for Mo, hydration-layer interactions and electrostatic interaction for Li, and hydrogen bonding for B, indicating the role of adsorptive membrane filtration. When applied to real groundwater samples, UF-CNC successfully reduced Li and B concentrations to permissible levels of Qatar while simultaneously lowering additional contaminants and maintaining stable performance with minimal fouling.
Overall, this study demonstrates the dual functionality of CNC-modified membranes in enhancing pollutant removal efficiency while sustaining membrane performance, highlighting their potential for sustainable groundwater treatment in arid regions
In Vitro and In Vivo Investigation of Locally Isolated Microalgae Strains for their Anti-Cancer Activity and Protective Effects against Heavy Metal Carcinogenicity
No full textHeavy-metal exposure, notably nickel (Ni), contributes to lung carcinogenesis through oxidative stress, hypoxia signaling, and epithelial-mesenchymal transition (EMT). This thesis investigated the anticancer potential of locally isolated microalgae for bioactivities relevant to Ni-carcinogenesis risk mitigation. Porphyridium purpureum (QUCCCM160) was prioritized for its high antioxidant capacity, proven Ni-biosorption, and favorable PE-extract properties (BET/cellular uptake), and was investigated for its anticancer and metallo-protective effects.
The anticancer activity was assessed using real-time cell analysis (RTCA) and Cell Counting Kit-8 (CCK-8) assays, revealing significant dose-dependent and selective inhibition of cancer cell proliferation across NSCLC cell lines. The IC50 values of the PE-rich extract on NCI-H1975, A549, and NCI-H322 were 14.87±2.64, 12.75 ± 3.42, and 11.73±1.58 μg/mL, respectively, compared to 41.19 ± 2.51 μg/mL for LL24 normal cells. Morphological observations and wound healing assays showed apoptotic-like changes and reduced migratory ability. Human apoptosis array confirmed the activation of both intrinsic and extrinsic apoptotic pathways. RT-qPCR data showed significant modulation of epithelial-mesenchymal transition (EMT) and migration-related gene expressions in a cell line– and stage–dependent manner, consistent with apoptosis induction and migration restraint.
The in vivo efficacy was evaluated in the zebrafish xenograft model, where Dillabeled A549 and NCI-H1975 (primary) and NCI-H322 (metastatic) NSCLC cells were injected into the zebrafish yolk and treated with 10 μg/mL PE-extract. Fluorescence imaging at 24 and 72 hours post-injection revealed that PE treatment significantly inhibited tumor growth in the primary (NCI-H1975, A549) cell xenografts, while NCI-H322 cells showed lower sensitivity, likely due to their metastatic aggressiveness.
Finally, metallo-protection was tested by cell exposure to Ni and pre-treatment with PE-extract. RTCA and wound-healing assays demonstrated attenuation of Ni²⁺-induced toxicity in both A549 and LL24, with preferential protection of non-malignant LL24 fibroblasts. In LL24, PE-extract reduced pro-inflammatory transcripts (TNFα, IL-1β, IL-6) and partially restored CDH1, in A549, PE-extract reduced IL-1β and further inhibited hypoxia/EMT drivers (HIF-1α, ZEB1).
Collectively, PE-extract combines anticancer activity in NSCLC (in vitro and in vivo) with metallo-protective effects against Ni²⁺-toxicity, showing selective protection of normal cells while constraining tumor-promoting programs. This dual profile supports the development of standardized PE-based interventions for adjunctive cancer prevention and mitigation of environmental Ni exposure impacts
PHARMACOPHORE-GUIDED VIRTUAL SCREENING FOR DRUG REPURPOSING AND BENZOFURAN LEAD OPTIMIZATION TOWARD SELECTIVE ALLOSTERIC MODULATION OF PROTEIN TYROSINE PHOSPHATASE 1B (PTP1B)
No full textProtein Tyrosine Phosphatase 1B (PTP1B) is a key negative regulator of insulin and leptin signaling and plays a central role in the development of insulin resistance and associated cardiometabolic disorders. Although PTP1B is a validated therapeutic target for type 2 diabetes, the clinical translation of active-site inhibitors has been hindered by poor selectivity, off-target effects, and limited bioavailability due to the high conservation of the catalytic pocket among protein tyrosine phosphatases. Allosteric inhibition has therefore emerged as a promising strategy for selectively modulating PTP1B activity. In this study, an integrated in silico and experimental approach was employed to identify and characterize selective allosteric inhibitors of PTP1B. A structure-based pharmacophore model targeting the allosteric site was developed and validated, and subsequently used to screen an FDA-approved drug library. In parallel, a series of in-house benzofuran derivatives was evaluated based on their structural suitability for allosteric binding. Top-ranked compounds were subjected to molecular docking at both the allosteric and catalytic sites of PTP1B, and the allosteric site of TC-PTP, followed by molecular dynamics simulations and MM/GBSA binding free energy calculations to assess binding stability, selectivity, and conformational effects on the WPD loop. The most promising candidates were experimentally evaluated using a recombinant PTP1B enzymatic inhibition assay. Several compounds demonstrated notable inhibitory activity and favorable selectivity profiles, supporting the computational predictions. Collectively, these findings highlight benzofuran-based scaffolds and repurposed FDA-approved drugs as promising leads for selective allosteric inhibition of PTP1B. This study provides a rational framework for the discovery of safer and more effective PTP1B-targeted therapeutics for metabolic disorders
Geopolitical risk, ESG Controversies, Trade Credit and Stock Liquidity
No full textWe study how geopolitical risk (GPR) affects firms’ use of trade credit (TC). Using a sample of 30,704 listed firms, from 42 countries, that are covered by the GPR index over the period 1990 to 2023, we show that trade credit is positively related to geopolitical risk. Moreover, we show the validity of financial constraints as a channel through which GPR affects TC. Furthermore, we show that the positive association between GPR and TC is stronger (weaker) in firms with high Environmental, Social, and Governance (ESG) performance (cash flow risk and product market competition). Additionally, utilizing a dataset comprising 12,084 firm-year observations from 32 countries between 2013 and 2022, we investigate the impact of (ESG) controversies on stock market liquidity, with a particular focus on the mediating role of GPR. Our analysis reveals a consistently positive and highly significant relationship between ESG controversies and stock liquidity, as measured by the natural logarithm of the Amihud illiquidity ratio (LN_AMIHUD), with this effect being more pronounced in regions experiencing high geopolitical instability. Moreover, we show that the ESG performance and the existing of sustainability committee mediate this relationship by enhancing stock liquidity. All results hold up under a series of robustness tests including the use of approaches to address endogeneity issues
Sustainable Water Reuse: Green Polymer, Ionic Liquid, and Peroxidase-modified Graphene Oxides Composites for Remediation of Phenolic Wastewater
No full textBased on the results of Langmuir Qmax values at pH 6 and 40 °C, adsorption performance showed a clear dependence on adsorbent type and surface chemistry. For phenol, the adsorption capacity followed the order AC-PJ (52.35 mg/g) > AC (34.84 mg/g) > GO-PAA (11.49 mg/g) > GO-ILs (9.09 mg/g) > GO (5.46 mg/g), highlighting the superior performance of biomass-derived activated carbon and the limited capacity of pristine and modified GO. For bisphenol A, a much stronger contrast was observed, with adsorption following AC-PJ (454.55 mg/g) ≫ AC (105.26 mg/g) > GO (63.29 mg/g) > GO-ILs (38.46 mg/g) > GO-PAA (16.67 mg/g). In general, AC-PJ exhibited the highest adsorption capacities for both pollutants at pH 6 and 40 °C, with a particularly pronounced advantage for BPA, confirming the dominant role of carbon-rich surfaces and favorable pore structures under these conditions.
Peroxidase-assisted degradation further improved pollutant removal, achieving up to ~95% BPA and ~80% phenol removal under optimal conditions (2mM H2O2, 0.1 U/mL enzyme, pH 6, 40 °C). The process remained effective under moderate salinity, confirming the enzyme’s tolerance to ionic strength. Overall, the study demonstrated that enzymatic oxidation significantly enhanced the removal of phenolic pollutants. Enzyme loaded GO-PJP showed a pronounced enhancement in phenol removal compared with pristine GO, achieving more than a twofold improvement at intermediate concentrations due to synergistic adsorption–enzymatic oxidation, whereas BPA removal showed only limited and concentration-dependent improvement.
In continuous-flow column experiments, activated carbon sustained the longest breakthrough performance, achieving dynamic capacities of 160.00 mg/ g for phenol and 559.08 mg/g for BPA, with breakthrough times of 177.78 min and 354.91 min, respectively. Graphene oxide showed faster kinetics but earlier exhaustion, with phenol capacities of 79.37 mg/g and BPA capacities of 40.20 mg/g, and breakthrough times of 62.43 min for phenol and 39.37 min for BPA. Thomas, Yoon-Nelson, and Yan models provided strong fits (R2 up to 0.96), confirming that AC acted as a high-capacity, diffusion-dominated adsorbent, while GO functioned as a rapid-kinetic but lower-capacity material under continuous operation. These column findings corroborated the batch results and highlighted AC as the most efficient sorbent for sustained removal of phenolic pollutants.
These results highlighted the complementary roles of carbon-rich adsorbents for high-capacity removal and enzyme-assisted GO systems for catalytic enhancement, offering a promising and sustainable strategy for the treatment of phenolic contaminants in complex wastewater matrices
PFAS-contaminated groundwater treatment by forward osmosis using pressure-stimuli-responsive nanofiltration membrane: Effects of chain length and operating conditions
No full textSignificant health concerns have been raised resulting from the increasing detection of per- and polyfluoroalkyl substances (PFAS) in various water bodies. Attention has shifted beyond long-chain compounds, carbon-chain length ≥ C7, to include the more mobile and persistent short, carbon-chain length C4-C6, and ultra-short-chain PFAS, carbon-chain length C1-C3. This study systematically investigated the rejection of PFAS-contaminated groundwater using a pressure-stimuli-responsive nanofiltration (PSRNF) membrane with varying pressures and pH of the feed solution. The rejection efficiency of long- and short-chain PFAS by the PSRNF membrane increased with both increasing pressure and pH, achieving 99.1 % to 100 % for long chains and 96.9 % to 98 % for short chains. In contrast, the ultra-short-chain PFAS rejection efficiency by the PSRNF membrane decreased at acidic pH with increasing pressure, but increased at alkaline pH, achieving up to 91.4 %. There was a higher tendency for membrane adsorption of long-chain PFAS due to strong hydrophobic interactions at low pressure, resulting from a longer contact time with the membrane. Ultra-short-chain PFAS exhibited no adsorption across all conditions due to their low hydrophobicity and minimal affinity for the membrane surface. This performance was closely linked to both the physicochemical properties of the PFAS species and the operational environment, such as pH and applied pressure. These findings highlight both the practical benefits of the PSRNF membrane and the importance of optimising operating conditions for effective removal of PFAS and heavy metals from contaminated water
Divine Laws in Marital Relationships: Surah An-Nisa and Surah AtTalaq as a Model
No full textهذا البحث يُعنى بجمع واستقراء السنن الرَّبَّانِيَّة الجارية في العلاقة الزوجية باعتبارها قوانين وقواعد، ثم تأصيلها ودراستها في سورتي النساء والطلاق. شاع في زماننا آراء وأقوال حول قواعد الزواج الناجح، لا تتوافق بشكل كلي مع ما جاء به الدين الإسلامي من قيم حاكمة وردت في القرآن بصراحة، مثل: المودة، والرحمة، والصفح، والعفو، والإحسان، والفضل والتقوى والتوكل، والسعة في اللقاء أو الفراق الزوجي، هذا البحث يبين مواطن ورود موضوعات السُّنَن الرَّبَّانِيَّة الضابطة للعلاقة الزوجية في كتاب الله من سورتي النساء والطلاق بذكر مواطن ورودها، وصيغتها، ودلالاتها التربوية، وآثارها النفسية في حفظ الاستقرار بين الزوجين والسؤال المركزي الذي يجيب عنه البحث: ما السنن الرَّبَّانِيَّة التي تضمنتها سورتا النساء والطلاق في معالجة تحديات العلاقة الزوجية؟ وما أثر ذلك في استقرار العلاقة الزوجية؟ وهدفها الرئيس استنباط القواعد الكلية الحاكمة التي تقوي العلاقة الزوجية، وتوضح الطريقة المثلى للتعامل في حال الفراق الزوجي، فَإِمْسَاكُ بِمَعْرُوفٍ أَوْ تَسْرِيحُ بِإِحْسن (البقرة: 229). وقد اقتضت طبيعة البحث الاعتماد على المنهج الوصفي التحليلي وأدواته الاستقراء والاستنباط، والبحث يعتمد طريقة التفسير الموضوعي التوحيدي، وتضمن مدخلا تمهيديا، وفصلين، وخاتمة، تضمن التمهيد تعريفا عاما بعلم السُّنَنِ الرَّبَّانِيَّة في القرآن، وتناول الفصل الأول السنن الرَّبَّانِيَّة في العلاقة الزوجية من سورة النساء، التي تتعلق بالتحديات في العلاقة الزوجية، وتبين سبل معالجتها، وتناول الفصل الثاني السُّنَن الرَّبَّانِيَّة في العلاقة الزوجية من سورة الطلاق، حال (الفرقة الزوجية). ومن أهم نتائج البحث : أن علم السُّنَن الرَّبَّانِيَّة في القرآن الكريم يمكن توظيفه في علاج تحديات العلاقات الزوجية؛ إذ يظهر جليًا تكرار نماذج للعلاقات الزوجية عبر الأزمان مع تجدد التحديات بحسب معطيات كل عصر، والعلم بالسُّنَن الرَّبَّانِيَّة وتسخيرها في خدمة القضايا الإنسانية تتطلب دقة في تحديد الموضوع، وتخصيص دراسات مقيدة وممتدة في موضوع واحد، أي بالاستعانة بالمنهج الموضوعي الذي يخدم الأسرة المسلمة، أما أهم التوصيات في البحث: فهي ضرورة دراسة كتب التفسير الاجتماعي من منظور سنني؛ لمعالجة مشكلات الزواج والطلاق في الوطن العربي والإسلامي بمنهج رباني سُنَني شامل مضطرد، بدلا من منطلقات الفكر الغربي والشرقي والنظريات الوضعية التي تطبقها مراكز الإرشاد الأسري في العالم الإسلامي.This research aims to collect and extrapolate the divine laws applicable to marital relationships as laws and rules, then to establish and study them from Surah An-Nisa and Surah At-Talaq. In our time, opinions and sayings about the rules of a successful marriage have become widespread. These opinions and sayings are not entirely consistent with the governing values of Islam, explicitly mentioned in the Quran. These values include affection, mercy, forgiveness, pardon, benevolence, virtue, piety, trust in God, tolerance, and magnanimity, whether in marital life or parting. This research highlights the topics of divine laws regulating the marital relationship in the Quran, in light of Surah An-Nisa and Surah At-Talaq, by mentioning their occurrences, wording, educational connotations, and psychological effects in maintaining stability between spouses. The central question that this research answers is: What are the divine laws contained in Surah An-Nisa and Surah At-Talaq in addressing the challenges of the marital relationship? And what is this impact on the stability of the marital relationship? Its primary objective is to derive the general governing rules that strengthen the marital relationship and clarify the optimal method for dealing with marital separation: "Either keep (her ) in an acceptable manner or release (her ) with good treatment." (Al-Baqarah: 229 ) The nature of the research required relying on the descriptive analytical approach and its tools: induction and deduction. The research relies on the method of thematic monotheistic interpretation, and includes an introduction, two chapters, and a conclusion. The introduction consists of a general definition of the science of divine laws in the Qur'an. The first chapter addresses divine laws in the marital relationship from Surah AnNisa, addressing the challenges of the marital relationship. The second chapter addresses divine laws in the marital relationship from Surah AtTalaq, addressing the challenges of marital separation. One of the most important findings of the research is that the knowledge of divine laws in the Holy Quran can be employed to address the challenges of marital relations. Models of marital relationships have been repeated over time, with challenges evolving according to the circumstances of each era. Knowledge of divine laws and their application to serve humanitarian issues requires a precise subjective definition and allocating limited and extended studies to a single topic, utilizing an objective approach that serves the Muslim family. The most important recommendations of the research are the necessity of studying books of social interpretation from a Sunni perspective to address the problems of marriage and divorce in the Arab and Islamic world using a comprehensive and consistent divine and Sunni approach, rather than relying on Western and Eastern thought and the positivist theories applied by family guidance centers in the Islamic world
CYTOCHROME P450 3A5 (CYP3A5) GENOTYPE-GUIDED DOSING OF TACROLIMUS IN KIDNEY TRANSPLANTATION IN QATAR: A COST-EFFECTIVENESS ANALYSIS
No full textObjective: To summarize the evidence from the literature on the impact of various genotypes on tacrolimus pharmacokinetic and clinical outcomes in kidney transplant recipients, and to evaluate the cost effectiveness of a genotype guided dosing approach for tacrolimus in kidney transplantation in Qatar. Methods: The thesis constitutes two research phases. Phase one was a systematic review of published meta-analyses (MAs) assessing multiple genotypes that impact tacrolimus therapy outcomes in kidney transplantation. Phase two was an economic simulation-based decision analytic model, constructed from the Hamad Medical Corporation (HMC) perspective, to assess the cost of a genotype-guided dosing therapy approach versus a standard dosing therapy approach against achieving tacrolimus levels within the therapeutic range without adverse drug reactions (ADRs), over six-month follow up, in the kidney transplantation in Qatar. Results: CYP3A5 was most strongly associated with tacrolimus pharmacokinetic and clinical outcomes. Here, the CYP3A5 genotype-guided dosing approach is cost-effective in achieving target tacrolimus levels within the therapeutic range, without ADRs. One-way and multivariate sensitivity analyses confirmed the study outcome robustness. Conclusion: The CYP3A5 genotype-guided dosing of tacrolimus was a cost-effective approach of therapy, over short term follow up, relevant to the standard dosing approach in kidney transplantation in Qatar
The Impact of Temporal Proximity and Remoteness on Islamic Jurisprudential Rulings
No full textلا بد لأفعال المكلفين - من عبادات أو معاملات من زمان تقع فيه؛ إذ لا يتصور انفكاكها عن الزمن الذي هو ركن من أركان الحياة، ومن هنا تظهر أهمية النظر في الزمن قرباً وبعداً وما يكون له من أثر في أحكام المسائل الفقهية، وقد جاء هذا البحث ليبين أثر اختلاف المدة الزمنية قرباً وبعداً في أحكام المسائل الفقهية في أبواب العبادات والمعاملات، ومن ثم استخلاص القواعد الفقهية والمقاصدية الحاكمة لأثر القرب والبعد الزماني في المسائل الفقهية، وذلك باستخدام المنهج الاستقرائي التحليلي المقارن، وقد ظهر من خلال البحث أثر اختلاف المدة الزمنية قرباً وبعداً في أحكام المسائل الفقهية سواء أكان ذلك في أبواب العبادات أم المعاملات ففى العبادات قد يكون البعد الزماني مبطلاً للعبادة لما يترتب عليه من الفصل بين أجزائها بحيث يخل ذلك بصورتها وهيئتها الشرعية، وربما كان البعد الزماني المبطل للعبادة متعلقاً بذات العبادة وأجزائها أو يكون متعلقاً بشرط العبادة، أو ببعض مكملاتها، وأما في المعاملات فقد يؤثر طول الفصل الزماني في أركان العقد كالفصل بين الإيجاب والقبول عند من يشترط الفورية، أو يكون متعلقاً بما يشترطه العاقدان كاشتراط تأخير قبض المبيع المعين، واشتراط الخيار فيكون الزمن البعيد فيها مؤثراً في جواز الشرط وصحته، وتبين أن لهما تأثيراً أيضاً في باب النكاح والجنايات، كما ظهر من خلال البحث أيضاً العلاقة الوثيقة بين القواعد الفقهية وبين القرب والبعد الزماني في المسائل الفقهية، وتبين أيضاً وجه ارتباط تلك الأحكام الفقهية المنوطة بالقرب والبعد الزماني بالمقاصد الشرعية واستند البحث الى المنهج الاستقرائي والتحليلي والمقارن. وقد أوصت الباحثة في خاتمة البحث بالتوسع في الكتابة في هذا الباب ولا سيما من الناحية المقاصدية، كما أوصت بالمزيد من الكتابات المتعلقة بالقرب والبعد الزماني في أبواب المعاملات المعاصرة على وجه الخصوص.The actions of legally responsible individuals—whether in worship or in transactions—must necessarily take place within time, since time is an inseparable element of life. This highlights the importance of considering temporal proximity and remoteness and their impact on jurisprudential rulings. This study explores how differences in time duration—whether short or long—affect rulings in Islamic jurisprudence within both worship and transactional matters. It also seeks to identify the jurisprudential and maqāṣid-based (objectives of Sharia) principles that govern the role of time in these issues. The research follows a comparative, analytical, and inductive methodology. The findings show that variations in time duration do influence rulings. In acts of worship, long interruptions may invalidate the act by breaking its sequence and disrupting its proper legal form. Such invalidation may relate to the act itself, its conditions, or its supplementary aspects. In transactions, extended time gaps may affect essential elements of the contract, such as the link between offer and acceptance for those who require immediacy. They may also impact conditions agreed upon by the contracting parties, such as delaying receipt of a specified item or stipulating an option period, where the length of time determines the validity and permissibility of the condition. The study also finds similar implications in marriage and criminal law. Moreover, the research highlights the close connection between jurisprudential principles and temporal proximity/remoteness, and how such rulings are tied to the higher objectives of Sharia. In conclusion, the researcher recommends expanding work in this field, particularly from a maqāṣid perspective, and encourages more studies on the role of time in contemporary transactional issues