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  1. Structured student-generated videos for first-year students at a dental school in Malaysia
    Omar H, Khan SA, Toh CG
    J Dent Educ, 2013 May;77(5):640-7.
    PMID: 23658411
    Student-generated videos provide an authentic learning experience for students, enhance motivation and engagement, improve communication skills, and improve collaborative learning skills. This article describes the development and implementation of a student-generated video activity as part of a knowledge, observation, simulation, and experience (KOSE) program at the School of Dentistry, International Medical University, Kuala Lumpur, Malaysia. It also reports the students' perceptions of an activity that introduced first-year dental students (n=44) to clinical scenarios involving patients and dental team aiming to improve professional behavior and communication skills. The learning activity was divided into three phases: preparatory phase, video production phase, and video-watching. Students were organized into five groups and were instructed to generate videos addressing given clinical scenarios. Following the activity, students' perceptions were assessed with a questionnaire. The results showed that 86 percent and 88 percent, respectively, of the students agreed that preparation of the activity enhanced their understanding of the role of dentists in provision of health care and the role of enhanced teamwork. In addition, 86 percent and 75 percent, respectively, agreed that the activity improved their communication and project management skills. Overall, the dental students perceived that the student-generated video activity was a positive experience and enabled them to play the major role in driving their learning process.
  2. Utilization of debate as an educational tool to learn health economics for dental students in Malaysia
    Khan SA, Omar H, Babar MG, Toh CG
    J Dent Educ, 2012 Dec;76(12):1675-83.
    PMID: 23225687
    Health economics, a special branch of science applying economic principles to the health delivery system, is a relatively young subdiscipline. The literature is scanty about teaching health economics in the medical and dental fields. Delivery methods of this topic vary from one university to another, with lectures, seminars, and independent learning reported as teaching/learning tools used for the topic. Ideally, debates should foster the development of logical reasoning and communication skills. Health economics in dentistry is taught under the community oral health module that constitutes part of an outcome-based dental curriculum in a private dental school in Kuala Lumpur, Malaysia. For this study, the students were divided into two groups: active participants (active debaters) and supporting participants (nonactive debaters). The debate style chosen for this activity was parliamentary style. Active and nonactive debaters' perceptions were evaluated before and after the activity through a structured questionnaire using a five-point rating scale addressing the topic and perceptions about debate as an educational tool. Cronbach's alpha coefficient was used as a measure of internal consistency for the questionnaire items. Among a total of eighty-two third-year dental students of two successive cohorts (thirty-eight students and forty-four students), seventy-three completed the questionnaire, yielding a response rate of 89 percent. Students' responses to the questionnaire were analyzed with the Kruskal-Wallis analysis of variance test. Results revealed that the students felt that their interest in debate, knowledge of the topic, and reinforcement of the previous knowledge had improved following participation in the debate. Within the limitations of this study, it can be concluded that debate was a useful tool in teaching health economics to dental students.
  3. Fulltext Harnessing Machine Learning in Early COVID-19 Detection and Prognosis: A Comprehensive Systematic Review
    Dabbagh R, Jamal A, Bhuiyan Masud JH, Titi MA, Amer YS, Khayat A, et al.
    Cureus, 2023 May;15(5):e38373.
    PMID: 37265897 DOI: 10.7759/cureus.38373
    During the early phase of the COVID-19 pandemic, reverse transcriptase-polymerase chain reaction (RT-PCR) testing faced limitations, prompting the exploration of machine learning (ML) alternatives for diagnosis and prognosis. Providing a comprehensive appraisal of such decision support systems and their use in COVID-19 management can aid the medical community in making informed decisions during the risk assessment of their patients, especially in low-resource settings. Therefore, the objective of this study was to systematically review the studies that predicted the diagnosis of COVID-19 or the severity of the disease using ML. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA), we conducted a literature search of MEDLINE (OVID), Scopus, EMBASE, and IEEE Xplore from January 1 to June 31, 2020. The outcomes were COVID-19 diagnosis or prognostic measures such as death, need for mechanical ventilation, admission, and acute respiratory distress syndrome. We included peer-reviewed observational studies, clinical trials, research letters, case series, and reports. We extracted data about the study's country, setting, sample size, data source, dataset, diagnostic or prognostic outcomes, prediction measures, type of ML model, and measures of diagnostic accuracy. Bias was assessed using the Prediction model Risk Of Bias ASsessment Tool (PROBAST). This study was registered in the International Prospective Register of Systematic Reviews (PROSPERO), with the number CRD42020197109. The final records included for data extraction were 66. Forty-three (64%) studies used secondary data. The majority of studies were from Chinese authors (30%). Most of the literature (79%) relied on chest imaging for prediction, while the remainder used various laboratory indicators, including hematological, biochemical, and immunological markers. Thirteen studies explored predicting COVID-19 severity, while the rest predicted diagnosis. Seventy percent of the articles used deep learning models, while 30% used traditional ML algorithms. Most studies reported high sensitivity, specificity, and accuracy for the ML models (exceeding 90%). The overall concern about the risk of bias was "unclear" in 56% of the studies. This was mainly due to concerns about selection bias. ML may help identify COVID-19 patients in the early phase of the pandemic, particularly in the context of chest imaging. Although these studies reflect that these ML models exhibit high accuracy, the novelty of these models and the biases in dataset selection make using them as a replacement for the clinicians' cognitive decision-making questionable. Continued research is needed to enhance the robustness and reliability of ML systems in COVID-19 diagnosis and prognosis.
  4. Fulltext Heat Transfer Characteristics of Fullerene and Titania Nanotube Nanofluids under Agitated Quench Conditions
    Dennis Quadros J, Khan SA, T P, Iqbal Mogul Y, R H, Abbas M, et al.
    ACS Omega, 2022 Dec 27;7(51):47764-47783.
    PMID: 36591137 DOI: 10.1021/acsomega.2c05397
    Distilled water and aqueous fullerene nanofluids having concentrations of 0.02, 0.2, and 0.4 vol % and titania (titanium dioxide, TiO2) nanofluids of 0.0002, 0.002, and 0.02 vol % were analyzed for heat transfer characteristics. Quenching mediums were stirred at impeller speeds of 0, 500, 1,000, and 1,500 RPMs in a typical Tensi agitation system. During the quenching process, a metal probe made of ISO 9950 Inconel was used to record the temperature history. The inverse heat conduction method was used to calculate the spatial and temporal heat flux. The nanofluid rewetting properties were measured and matched to those of distilled water. The maximum mean heat flux was 3.26 MW/m2, and the quickest heat extraction was 0.2 vol % fullerene nanofluid, according to the results of the heat transfer investigation.
  5. Fulltext Microstructure, Mechanical Properties, and Corrosion Behavior of Boron Carbide Reinforced Aluminum Alloy (Al-Fe-Si-Zn-Cu) Matrix Composites Produced via Powder Metallurgy Route
    Meignanamoorthy M, Ravichandran M, Mohanavel V, Afzal A, Sathish T, Alamri S, et al.
    Materials (Basel), 2021 Aug 02;14(15).
    PMID: 34361508 DOI: 10.3390/ma14154315
    In this paper, Al-Fe-Si-Zn-Cu (AA8079) matrix composites with several weight percentages of B4C (0, 5, 10, and 15) were synthesized by powder metallurgy (PM). The essential amount of powders was milled to yield different compositions such as AA8079, AA8079-5 wt.%B4C, AA8079-10 wt.%B4C, and AA8079-15 wt.%B4C. The influence of powder metallurgy parameters on properties' density, hardness, and compressive strength was examined. The green compacts were produced at three various pressures: 300 MPa, 400 MPa, and 500 MPa. The fabricated green compacts were sintered at 375 °C, 475 °C, and 575 °C for the time period of 1, 2 and 3 h, respectively. Furthermore, the sintered samples were subjected to X-ray diffraction (XRD) analysis, Energy Dispersive Analysis (EDAX), and Scanning Electron Microscope (SEM) examinations. The SEM examination confirmed the uniform dispersal of B4C reinforcement with AA8079 matrix. Corrosion behavior of the composites samples was explored. From the studies, it is witnessed that the rise in PM process parameters enhances the density, hardness, compressive strength, and corrosion resistance.
  6. Fulltext Challenges and Opportunities of Low Viscous Biofuel-A Prospective Review
    Ramalingam K, Vellaiyan S, Venkatesan EP, Khan SA, Mahmoud Z, Saleel CA
    ACS Omega, 2023 May 16;8(19):16545-16560.
    PMID: 37214702 DOI: 10.1021/acsomega.3c00387
    Under the roof of solid industrialization and accelerated intensification of multiple ranges of mobilization, a huge rise in precious fuel consumption and pollution was observed. Based on the recent hardships of fossil fuels, experts are undoubtedly eager in carrying out their research in renewable environment-friendly fuels. There have been many reviews of works considering the parameters and standards of biodiesel, which is only from various vegetable and seed oils. But very little review work was carried out on only plant-based biofuel. Plant-based fuel has a lower viscosity and higher volatility properties. The target of this review was to make a bridge to overcome these research gaps. This review extensively studies the biological background, production outcome, properties, and reliability of plant-based biofuel and also deeply investigates the feasibility of usage in a diesel engine. From deep investigation it was identified that most of the low viscous fuel had higher brake thermal efficiency (BTE) (2% to 4%) and NOx emission (5% to 10%) than high viscous biodiesel. The formation of hydrocarbon (HC), CO, and smoke emission was similar to high viscous biodiesel. Overall, the low viscous fuel effectively improves the engine behaviors.
  7. Fulltext Performance and Emission Analysis of Biodiesel Blends in a Low Heat Rejection Engine with an Antioxidant Additive: An Experimental Study
    Venkatesan EP, Rajendran S, Murugan M, Medapati SR, Ramachandra Murthy KVS, Alwetaishi M, et al.
    ACS Omega, 2023 Oct 10;8(40):36686-36699.
    PMID: 37841135 DOI: 10.1021/acsomega.3c02742
    The rapid depletion of crude oil and environmental degradation necessitate the search for alternative fuel sources for internal combustion engines. Biodiesel is a promising alternative fuel for compression ignition (CI) engines due to its heat content and combustion properties. Biodiesel blends are used in various vehicles and equipment, such as cars, trucks, buses, off-road vehicles, and oil furnaces. Biodiesel can reduce emissions from CI engines by up to 75% and improve engine durability due to its high lubricity. However, biodiesel has some drawbacks, including a performance reduction and increased nitrogen oxide emissions. Therefore, this study aims to investigate using environmentally available biodiesel in a low-heat rejection engine and an antioxidant additive to enhance the performance and reduce nitrogen oxide emissions. India currently has several biodiesel sources, including mango seed oil, mahua oil, and pongamia oil, which can be effectively utilized in CI engines by adding l-ascorbic acid. The experimental work involves a single-cylinder 4-stroke water-cooled direct injection CI engine with a power output of 5.2 kW. The engine's cylinder head, piston head, and valves are coated with lanthanum oxide using the plasma spray coating technique, with a thickness of 0.5 mm. The coated and uncoated engines are tested with different proportions of mahua oil, mango seed oil, and pongamia oil. The results show that the engine's performance is significantly improved compared to the baseline engine at all loads. Additionally, these biodiesels exhibit a notable reduction in nitrogen oxide emissions when combined with l-ascorbic acid.
  8. Effect of gasotransmitters treatment on expression of hypertension, vascular and cardiac remodeling and hypertensive nephropathy genes in left ventricular hypertrophy
    Ahmad A, Riaz Z, Sattar MA, Khan SA, John EJ, Rashid S, et al.
    Gene, 2020 May 05;737:144479.
    PMID: 32068124 DOI: 10.1016/j.gene.2020.144479
    BACKGROUND: Cardiac and renal dysfunction are often co-morbid pathologies leading to worsening prognosis resulting in difficulty in therapy of left ventricular hypertrophy (LVH). The aim of the current study was to determine the changes in expression of human ortholog genes of hypertension, vascular and cardiac remodeling and hypertensive nephropathy phenotypes under normal, disease and upon treatment with gasotransmitter including H2S (hydrogen sulphide), NO (nitric oxide) and combined (H2S + NO).

    METHODS: A total of 72 Wistar Kyoto rats (with equivalent male and female animals) were recruited in the present study where LVH rat models were treated with H2S and NO individually as well as with both combined. Cardiac and renal physical indices were recorded and relative gene expression were quantified.

    RESULTS: Both cardiac and renal physical indices were significantly modified with individual as well as combined H2S + NO treatment in control and LVH rats. Expression analysis revealed, hypertension, vascular remodeling genes ACE, TNFα and IGF1, mRNAs to be significantly higher (P ≤ 0.05) in the myocardia and renal tissues of LVH rats, while individual and combined H2S + NO treatment resulted in lowering the gene expression to normal/near to normal levels. The cardiac remodeling genes MYH7, TGFβ, SMAD4 and BRG1 expression were significantly up-regulated (P ≤ 0.05) in the myocardia of LVH where the combined H2S + NO treatment resulted in normal/near to normal expression more effectively as compared to individual treatments. In addition individual as well as combined H2S and NO treatment significantly decreased PKD1 expression in renal tissue, which was up-regulated in LVH rats (P ≤ 0.05).

    CONCLUSIONS: The reduction in hemodynamic parameters and cardiac indices as well as alteration in gene expression on treatment of LVH rat model indicates important therapeutic potential of combined treatment with H2S + NO gasotransmitters in hypertension and cardiac hypertrophy when present as co-morbidity with renal complications.

  9. Teledentistry in practice: literature review
    Khan SA, Omar H
    Telemed J E Health, 2013 Jul;19(7):565-7.
    PMID: 23672799 DOI: 10.1089/tmj.2012.0200
    Teledentistry can be defined as the remote provision of dental care, advice, or treatment through the medium of information technology, rather than through direct personal contact with any patient(s) involved. Within dental practice, teledentistry is used extensively in disciplines like preventive dentistry, orthodontics, endodontics, oral surgery, periodontal conditions, detection of early dental caries, patient education, oral medicine, and diagnosis. Some of the key modes and methods used in teledentistry are electronic health records, electronic referral systems, digitizing images, teleconsultations, and telediagnosis. All the applications used in teledentistry aim to bring about efficiency, provide access to underserved population, improve quality of care, and reduce oral disease burden.
  10. Fulltext Role of ethical beliefs and attitudes of dental students in providing care for HIV/AIDS patients
    Khan SA, Liew ML, Omar H
    Saudi Dent J, 2017 Jan;29(1):7-14.
    PMID: 28270704 DOI: 10.1016/j.sdentj.2016.08.005
    INTRODUCTION: Dental care has remained as an unmet need for people living with HIV/AIDS (PLWHAs). Dental students are considered as future healthcare workforce and having beliefs which are discriminating may have negative attitudes towards providing care to these individuals (Azodo et al., 2010). The study aimed to assess the ethical beliefs and attitudes of dental students towards PLWHAs for providing care.
    METHODS: It is a descriptive correlational and cross sectional study. Nine public and private dental schools in Malaysia participated in the study. Data was collected using a validated self-administered questionnaire.
    RESULTS: A total of 481 dental students participated in this study, yielding response rate of 78%. Majority of the participants (74%) believed that patients' HIV status should be disclosed to patients' sexual partner without permission. Approximately 60% of the participants reported that rooms/beds of HIV patients should be clearly marked. Regarding patient disease status 28% of the students reported that it is appropriate to test a patient for HIV/AIDS without patient's permission. Only Fifty five percent of the students expressed the willingness to treat HIV patients and 49% reported to held fear of getting infected while treating patients with HIV/AIDS. Sixty four percent of the participants reported to be more comfortable giving care to non-HIV patients than HIV-positive patients.
    CONCLUSION: Dental students' ethical beliefs about HIV/AIDS were not consistent with the ethical principles as stated in the code of ethics and they held negative attitudes towards PLWHAs. Ethical beliefs were found to be a determinant that may influence future attitudes of these students towards individuals with HIV/AIDS when providing care.
  11. Patients' Readiness Towards Teledentistry in the Malaysian Urban Population Attending an Undergraduate Teaching University
    Zain E, Rahman N, Khan SA, Farook MS, Khan E, Jubapu AS, et al.
    Telemed J E Health, 2024 Jan;30(1):214-222.
    PMID: 37358591 DOI: 10.1089/tmj.2023.0075
    Introduction: COVID-19 disease has resulted in suspension of all nonurgent routine dental treatments. In view of COVID-19 situation, social distancing, movement restriction orders, and affected health care systems, there is an urgent need to resume and deliver oral health care remotely. Hence, alternative means of dental care should be available for both patients and dentists. Therefore, this study aims to assess patients' readiness for teledentistry in Malaysian urban population attending an undergraduate teaching university. Methods: A cross-sectional study was conducted among 631 adult patients visiting the Faculty of Dentistry, SEGi University, from January 2020 to May 2021 in Selangor, Malaysia. A validated, self-administered, 5-point Likert scale online questionnaire comprising five domains was administered. (1) Patients' demographics and dental history, (2) patients' access to teledentistry, (3) patients' understanding towards teledentistry, (4) patients' willingness, and (5) barriers in using teledentistry were used to collect the required information. Results: Six hundred and thirty-one (n = 631) participants responded to the questionnaire. Ninety percent of patients were able to connect to Wi-Fi services independently and 77% participants were comfortable using online communication platforms. Seventy-one percent of the participants agreed that video and telephone clinics can reduce chances of infection rather than face-to-face consultation during the pandemic. Fifty-five percent of patients felt that virtual clinics would save time and 60% thought it could reduce travelling costs. Fifty-one percent showed their willingness to use video or telephone clinics when implemented at onsite clinics. Conclusion: Our study shows the readiness of patients to accept teledentistry as an alternative method of oral care if appropriate training and education are provided. The results of this study have prompted an increase in patients' education and shown a need to train clinicians and patients to integrate this technology at SEGi University. This might facilitate unhindered dental consultation and care in all situations.
  12. Fulltext A Comprehensive Review on Chemical and Pharmacological Potential of Viola betonicifolia: A Plant with Multiple Benefits
    Rizwan K, Khan SA, Ahmad I, Rasool N, Ibrahim M, Zubair M, et al.
    Molecules, 2019 Aug 29;24(17).
    PMID: 31470508 DOI: 10.3390/molecules24173138
    Viola betonicifolia (Violaceae) is commonly recognized as "Banafsha" and widely distributed throughout the globe. This plant is of great interest because of its traditional, pharmacological uses. This review mainly emphases on morphology, nutritional composition, and several therapeutic uses, along with pharmacological properties of different parts of this multipurpose plant. Different vegetative parts of this plant (roots, leaves, petioles, and flowers) contained a good profile of essential micro- and macronutrients and are rich source of fat, protein, carbohydrates, and vitamin C. The plant is well known for its pharmacological properties, e.g., antioxidant, antihelminthic, antidepressant, anti-inflammatory, analgesic, and has been reported in the treatment of various neurological diseases. This plant is of high economic value. The plant has potential role in cosmetic industry. This review suggests that V. betonicifolia is a promising source of pharmaceutical agents. This plant is also of significance as ornamental plant, however further studies needed to explore its phytoconstituents and their pharmacological potential. Furthermore, clinical studies are needed to use this plant for benefits of human beings.
  13. Hazardous heavy metals contamination of vegetables and food chain: Role of sustainable remediation approaches - A review
    Kumar S, Prasad S, Yadav KK, Shrivastava M, Gupta N, Nagar S, et al.
    Environ Res, 2019 12;179(Pt A):108792.
    PMID: 31610391 DOI: 10.1016/j.envres.2019.108792
    This review emphasizes the role of toxic metal remediation approaches due to their broad sustainability and applicability. The rapid developmental processes can incorporate a large quantity of hazardous and unseen heavy metals in all the segments of the environment, including soil, water, air and plants. The released hazardous heavy metals (HHMs) entered into the food chain and biomagnified into living beings via food and vegetable consumption and originate potentially health-threatening effects. The physical and chemical remediation approaches are restricted and localized and, mainly applied to wastewater and soils and not the plant. The nanotechnological, biotechnological and genetical approaches required to more rectification and sustainability. A cellular, molecular and nano-level understanding of the pathways and reactions are responsible for potentially toxic metals (TMs) accumulation. These approaches can enable the development of crop varieties with highly reduced concentrations of TMs in their consumable foods and vegetables. As a critical analysis by authors observed that nanoparticles could provide very high adaptability for both in-situ and ex-situ remediation of hazardous heavy metals (HHMs) in the environment. These methods could be used for the improvement of the inbuilt genetic potential and phytoremediation ability of plants by developing transgenic. These biological processes involve the transfer of gene of interest, which plays a role in hazardous metal uptake, transport, stabilization, inactivation and accumulation to increased host tolerance. This review identified that use of nanoremediation and combined biotechnological and, transgenic could help to enhance phytoremediation efficiency in a sustainable way.
  14. Fulltext Epidemiology and phylogeny of Haemonchus contortus through internal transcribed spacer 2 gene in small ruminants
    Ahmad N, Khan SA, Majid HA, Ali R, Ullah R, Bari A, et al.
    Front Vet Sci, 2024;11:1380203.
    PMID: 38655530 DOI: 10.3389/fvets.2024.1380203
    INTRODUCTION: Haemonchus contortus (H. contortus) is a blood-feeding nematode causing infectious disease haemonchosis in small ruminants of tropical and subtropical regions around the world. This study aimed to explore the prevalence and phylogeny of H. contortus in small ruminants using the internal transcribed spacer-2 (ITS-2) gene. In addition, a comprehensive review of the available literature on the status of H. contortus in Pakistan was conducted.

    METHODS: Fecal samples were collected from sheep and goats (n = 180). Microscopically positive samples were subjected to DNA extraction followed by PCR using species-specific primers.

    RESULTS: The overall prevalence of H. contortus was 25.55% in small ruminants. The prevalence of H. contortus was significantly associated with months and area. The highest occurrence of haemonchosis was documented in July (38.70%), whereas the lowest occurred in December (11.11%), with significant difference. The prevalence was highest in the Ghamkol camp (29.4%) and lowest in the arid zone of the Small Ruminant Research Institute (17.5%) (p = 0.01). The results of the systematic review revealed the highest prevalence of haemonchosis (34.4%) in Khyber Pakhtunkhwa (p = 0.001).

    DISCUSSION: Phylogenetic analysis revealed a close relationship between H. contortus and isolates from Asia (China, India, Iran, Bangladesh, Malaysia, and Mongolia) and European countries (Italy and the United Kingdom). It has been concluded that H. contortus is prevalent in small ruminants of Kohat district and all over Pakistan, which could be a potential threat to food-producing animals, farmers, dairy, and the meat industry. Phylogenetic analysis indicates that H. contortus isolates share close phylogenetic relationships with species from Asia and Europe.

  15. Experimental Studies to Reduce Usage of Fossil Fuels and Improve Green Fuels by Adopting Hydrogen-Ammonia-Biodiesel as Trinary Fuel for RCCI Engine
    Ramachandran E, Krishnaiah R, Perumal Venkatesan E, Medapati SR, Sabarish R, Khan SA, et al.
    ACS Omega, 2024 Jan 09;9(1):741-752.
    PMID: 38222659 DOI: 10.1021/acsomega.3c06327
    This study investigates the feasibility of hydrogen addition to achieve lower emissions and higher thermal efficiency in an ammonia-biodiesel-fueled reactivity-controlled compression ignition (RCCI) engine. A single-cylinder light-duty water-cooled compression ignition (CI) engine was adapted to run in RCCI combustion with port-injected ammonia and hydrogen as low reactive fuel (LRF) and direct-injected algal biodiesel as high reactive fuel (HRF). In our earlier study, the ammonia substitution ratio (ASR) was optimized as 40%. To optimize fuel and engine settings, hydrogen is added in quantities ranging from 5 to 20% by energy share. The combustion, performance, and emission characteristics were investigated for the trinary fuel operation. The result shows that the 20% hydrogen premixing with 40% ammonia-biodiesel RCCI operation increased the peak cylinder pressure (CP), peak heat release rate (HRR), and cumulative heat release rate (CHRR) by 15.12, 25.15, and 26.68%, respectively. Ignition delay (ID) and combustion duration (CD) were decreased by 15.53 and 11.24%, respectively. The combustion phasing angle was advanced by 4 °CA. The brake thermal efficiency (BTE) was improved by 15.49%, and brake specific energy consumption (BSEC) was reduced by 21.92%. While the nitrogen oxide (NOx) level was significantly increased by about 31.82%, the hydrocarbon (HC), carbon monoxide (CO), smoke, and exhaust gas temperature (EGT) were reduced by 24.53, 28.16, 25.82, and 17.47% as compared to the optimized ASR40% combustion.
  16. Fulltext Compatibility Effects of Waste Cooking Oil Biodiesel Blend on Fuel System Elastomers in Compression Ignition Engines
    Venkatesan EP, Krishnaiah R, Prasad K, Medapati SR, Sree SR, Asif M, et al.
    ACS Omega, 2024 Feb 13;9(6):6709-6718.
    PMID: 38371774 DOI: 10.1021/acsomega.3c07871
    Alternative energy sources, such as biodiesel, play a vital role in environmental protection. Waste cooking oil (WCO) biodiesel has promising applications in compression ignition engines. A major problem regarding biodiesel implementation is the deterioration and materials incompatibility of existing fuel system components with biodiesel. Variations in the composition of fuel prompted by the inclusion of biodiesel cause a variety of issues in diesel engine fuel systems where the elastomer is generally utilized as the fuel hose material and sealings. In this experimental work, the effects of the diesel and WCO biodiesel blends (B8, B16, B24, and B100) on Buna-N, ethylene propylene rubber (EPR), and polystyrene (PS) were examined by the immersion test, which was conducted for 160 h at various immersion temperatures of 30, 60, and 80 °C, respectively. The study also showed that the use of elastomer materials like Buna-N, EPR, and PS in diesel engines fueled up to 20% WCO biodiesel blends is advantageous; the overall compatibility improves by 100% compared to that obtained using neat diesel. The outcome revealed remarkable behavior changes, including a minor increase in volume and a slight loss in tensile strength and hardness compared to that observed using neat diesel fuel. The expansion of rubber materials increases over 60 °C, although the rate of this process decreases above 80 °C. It has been found that the expansion of rubber materials is unaffected by the acid concentration of the WCO biodiesel blends but significantly affected by the moisture content.
  17. Fulltext Entropy-based financial asset pricing: Evidence from Pakistan
    Wang S, Khan SA, Munir M, Alhajj R, Khan YA
    PLoS One, 2022;17(12):e0278236.
    PMID: 36548250 DOI: 10.1371/journal.pone.0278236
    Entropy is an alternative measure to calculate the risk, simplify the portfolios and equity risk premium. It has higher explanatory power than capital asset price model (CAPM) beta. The comparison of Entropy and CAPM beta provide in depth analysis about the explanatory power of the model that in turn help investor to make right investment decisions that minimizes risk. In this context, this study aims to compare Shannon and Rennyi Entropies with the CAPM beta for measuring the risk. Ordinary Least square approach has been utilized using a dataset of 67 enterprises registered in Pakistan Stock exchange. The comparative analysis of CAPM beta and entropy has been carried out with the R2 parameters. The result indicates that entropy has more explanatory power as compare to CAPM beta's explanatory power, and this turns out to be the best option to evaluate the risk performances. The result implies that an investor should make the best investment decision by choosing an enterprise that provide with good returns at minimum risk based on entropy technique.
  18. Fulltext Assessment of potential drug-drug interactions and its associated factors in the hospitalized cardiac patients
    Murtaza G, Khan MY, Azhar S, Khan SA, Khan TM
    Saudi Pharm J, 2016 Mar;24(2):220-5.
    PMID: 27013915 DOI: 10.1016/j.jsps.2015.03.009
    Drug-drug interactions (DDIs) may result in the alteration of therapeutic response. Sometimes they may increase the untoward effects of many drugs. Hospitalized cardiac patients need more attention regarding drug-drug interactions due to complexity of their disease and therapeutic regimen. This research was performed to find out types, prevalence and association between various predictors of potential drug-drug interactions (pDDIs) in the Department of Cardiology and to report common interactions. This study was performed in the hospitalized cardiac patients at Ayub Teaching Hospital, Abbottabad, Pakistan. Patient charts of 2342 patients were assessed for pDDIs using Micromedex® Drug Information. Logistic regression was applied to find predictors of pDDIs. The main outcome measure in the study was the association of the potential drug-drug interactions with various factors such as age, gender, polypharmacy, and hospital stay of the patients. We identified 53 interacting-combinations that were present in total 5109 pDDIs with median number of 02 pDDIs per patient. Overall, 91.6% patients had at least one pDDI; 86.3% were having at least one major pDDI, and 84.5% patients had at least one moderate pDDI. Among 5109 identified pDDIs, most were of moderate (55%) or major severity (45%); established (24.2%), theoretical (18.8%) or probable (57%) type of scientific evidence. Top 10 common pDDIs included 3 major and 7 moderate interactions. Results obtained by multivariate logistic regression revealed a significant association of the occurrence of pDDIs in patient with age of 60 years or more (p 
  19. Effect of CAD-CAM porcelain veneers thickness on their cemented color
    Omar H, Atta O, El-Mowafy O, Khan SA
    J Dent, 2010;38 Suppl 2:e95-9.
    PMID: 20493232 DOI: 10.1016/j.jdent.2010.05.006
    To determine the effect of thickness of porcelain veneers constructed from CAD-CAM on their final color when two resin cements were used.
  20. Surface characterization analysis of failed dental implants using scanning electron microscopy
    Daood U, Bandey N, Qasim SB, Omar H, Khan SA
    Acta Odontol Scand, 2011 Nov;69(6):367-73.
    PMID: 21449690 DOI: 10.3109/00016357.2011.569507
    To investigate the failure of 15 dental implants (Paragon/Zimmer) in relation to their surface quality.
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