4,656 results on '"Mohammad G"'
Search Results
52. Submandibular salivary gland involvement in granulomatosis with polyangiitis
- Author
-
Mohamed F. Abdelghany and Mohammad G. A. Khalaf
- Subjects
ANCA ,granulomatosis with polyangiitis ,salivary gland ,Wegener’s ,granulomatosis ,Diseases of the respiratory system ,RC705-779 ,Medical emergencies. Critical care. Intensive care. First aid ,RC86-88.9 - Abstract
Abstract Introduction Granulomatosis with polyangiitis (GPA) is one of the forms of small vessel vasculitis. It is a rare condition that needs a high degree of suspicion to reach the diagnosis. It is one of the causes of diffuse parenchymal lung disease, with a very wide differential diagnosis. It is commonly misdiagnosed with malignant, granulomatous, and infectious lung diseases. Case presentation We report a case of a 31-year-old male who presented with productive cough, shortness of breath, hemoptysis, nasal obstruction, and epistaxis together with submandibular salivary gland swelling. Diagnosis of GPA was based on characteristic cavitary lung lesions, nasal and salivary gland involvement, pathological samples that revealed necrotizing granulomatous inflammation, characteristic positive Cytoplasmic- ANCA (C-ANCA), together with exclusion of malignancy and tuberculosis. Conclusion GPA is a rare condition. Salivary gland involvement should raise suspicion about GPA, in addition to other systemic manifestations.
- Published
- 2020
- Full Text
- View/download PDF
53. Electrical and Structural properties of Copper Oxide (CuO) thin films on Plastic substrate deposited by spray pyrolysis technique
- Author
-
Mohammad G. Faraj, Askander K. Kaka, and Halo D. Omar
- Subjects
copper oxide, chemical spray pyrolysis, thin film, polyimide ,Technology ,Science - Abstract
In this paper, copper oxide (CuO) thin films were deposited on polyimide (PI) Plastic substrates with spray pyrolysis technique with different temperatures (i.e. 250–300 °C). All the deposited films were characterized by X-ray diffraction (XRD) and Hall Effect measurements for the Structural and electrical properties. Effects of substrate temperature on the structural and electrical characteristics of the films were studied. The X-ray diffraction patterns’ results reveal that the all of CuO films have a face centered cubic structure. The crystallite grain size was calculated using Scherrer formula and it is found that the substrate temperature (300 0C) has maximum crystallite grain size (81.2 nm). Hall Effect measurements showed that all the films are of p-type conductivity. Depending on the substrate temperature, Hall measurement showed that the electrical resistivity and the carrier concentration varied in the range 77.4 Ω.cm to 52.7 Ω.cm and 6.3 x1015 cm-3 to 10.1 x1015 cm-3.
- Published
- 2019
- Full Text
- View/download PDF
54. New Hydrogen-Bond-Enriched 1,3,5-Tris(2-hydroxyethyl) Isocyanurate Covalently Functionalized MCM-41: An Efficient and Recoverable Hybrid Catalyst for Convenient Synthesis of Acridinedione Derivatives
- Author
-
Zahra Alirezvani, Mohammad G. Dekamin, and Ehsan Valiey
- Subjects
Chemistry ,QD1-999 - Published
- 2019
- Full Text
- View/download PDF
55. The potential of utilising papaya seed oil and stone fruit kernel oil as non-edible feedstock for biodiesel production in Australia—A review
- Author
-
Mohammad Anwar, Mohammad G. Rasul, Nanjappa Ashwath, and MD. Nurun Nabi
- Subjects
Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
This paper reviews and discusses the potential of papaya seed and stone fruit kernel biodiesels — the two sources of 2nd generation transport biodiesels in Australia. The challenges associated with biodiesel production and their possible solutions, particularly on feedstock selection, oil extraction, conversion of oil into biodiesel, biodiesel storage and transport, costs of production and the information needs for commercialising these sources of biodiesels are discussed, along with the eco-friendly attributes of these biodiesels to Australian transport sector. Some researchers report that the use of papaya seed and stone fruit kernel biodiesels reduce engine power only 2 to 5%), however significantly reduce harmful engine emission such as HC reductions of 9 to 19%, PM reductions of 19.5 to 35% and CO reductions of 11 to 29%. Keywords: Papaya seed, Stone fruit kernel, Apricot, RSM, Biodiesel, Renewable energy, Australia, Optimisation, Challenges, Engine performance, Emission, Second generation
- Published
- 2019
- Full Text
- View/download PDF
56. Synthesis of Carboxymethyl Chitosan and Its Derivatives Using KI and/or Ultrasonication
- Author
-
Mahsa Rajabi, Mohammad Dohendou, and Mohammad G. Dekamin
- Subjects
chitosan ,carboxymethyl chitosan (CMC) ,ultrasonication ,Chemistry ,QD1-999 - Abstract
Chitosan is a natural polysaccharide that is mainly obtained from the shell of marine crustaceans including crabs, lobsters, shrimps, etc. Chitosan has been widely used in biomedicine due to its special characteristics of low toxicity, biocompatibility, biodegradation, and low immunogenicity. However, owing to the limited solubility of CS in water, its water-soluble derivatives are preferred for the mentioned applications. Carboxymethyl chitosan (CMC) is one of the water-soluble derivatives of chitosan, which has antibacterial, anticancer, antitumor, antifungal, antioxidant properties, and is used in both drug delivery and enzyme delivery. This material is also utilized in tissue engineering, wound healing, and bioimaging. For these reasons, in this article, a different and novel method by using KI and/or ultrasonication is proposed.
- Published
- 2022
- Full Text
- View/download PDF
57. Kinetic Modelling of Esterification and Transesterification Processes for Biodiesel Production Utilising Waste-Based Resource
- Author
-
M. A. Hazrat, Mohammad G. Rasul, Mohammad M. K. Khan, Nanjappa Ashwath, Arridina S. Silitonga, I. M. R. Fattah, and T. M. Indra Mahlia
- Subjects
biodiesel ,esterification ,transesterification ,optimisation ,reaction kinetics ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
Process optimisation and reaction kinetic model development were carried out for two-stage esterification-transesterification reactions of waste cooking oil (WCO) biodiesel. This study focused on these traditional processes due to their techno-economic feasibility, which is an important factor before deciding on a type of feedstock for industrialisation. Four-factor and two-level face-centred central composite design (CCD) models were used to optimise the process. The kinetic parameters for the esterification and transesterification processes were determined by considering both pseudo-homogeneous irreversible and pseudo-homogeneous first-order irreversible processes. For the esterification process, the optimal conditions were found to be an 8.12:1 methanol to oil molar ratio, 1.9 wt.% of WCO for H2SO4, and 60 °C reaction temperature for a period of 90 min. The optimal process conditions for the transesterification process were a 6.1:1 methanol to esterified oil molar ratio, 1.2 wt.% of esterified oil of KOH, reaction temperature of 60 °C, and a reaction time of 110 min in a batch reactor system; the optimal yield was 99.77%. The overall process conversion efficiency was found to be 97.44%. Further research into reaction kinetics will aid in determining the precise reaction process kinetic analysis in future.
- Published
- 2022
- Full Text
- View/download PDF
58. Growth State-Dependent Expression of Arachidonate Lipoxygenases in the Human Endothelial Cell Line EA.hy926
- Author
-
Mohammad G. Sabbir, Jeffrey T. Wigle, Carla G. Taylor, and Peter Zahradka
- Subjects
endothelial cells ,lipoxygenase ,phenotype ,bioactive lipids ,Cytology ,QH573-671 - Abstract
Endothelial cells regulate vascular homeostasis through the secretion of various paracrine molecules, including bioactive lipids, but little is known regarding the enzymes responsible for generating these lipids under either physiological or pathophysiological conditions. Arachidonate lipoxygenase (ALOX) expression was therefore investigated in confluent and nonconfluent EA.h926 endothelial cells, which represent the normal quiescent and proliferative states, respectively. mRNAs for ALOX15, ALOX15B, and ALOXE3 were detected in EA.hy926 cells, with the highest levels present in confluent cells compared to nonconfluent cells. In contrast, ALOX5, ALOX12, and ALOX12B mRNAs were not detected. At the protein level, only ALOX15B and ALOXE3 were detected but only in confluent cells. ALOXE3 was also observed in confluent human umbilical artery endothelial cells (HUAEC), indicating that its expression, although previously unreported, may be a general feature of endothelial cells. Exposure to laminar flow further increased ALOXE3 levels in EA.hy926 cells and HUAECs. The evidence obtained in this study indicates that proliferative status and shear stress are both important factors that mediate endothelial ALOX gene expression. The presence of ALOX15B and ALOXE3 exclusively in quiescent human endothelial cells suggests their activity likely contributes to the maintenance of a healthy endothelium.
- Published
- 2022
- Full Text
- View/download PDF
59. Effects of sedation on clinical, gasometric, and respiratory muscle parameters in critically ill chronic obstructive pulmonary disease patients
- Author
-
Atef F. Alkarn, Mohamed F. Abdelghany, Mohammad G. A. Khalaf, Emad Z. Kamel, and Wafaa A. H. Gadalla
- Subjects
chronic obstructive pulmonary disease ,intensive care ,mechanical ventilation ,sedation ,Diseases of the respiratory system ,RC705-779 ,Medical emergencies. Critical care. Intensive care. First aid ,RC86-88.9 - Abstract
Abstract Background Severe chronic obstructive pulmonary disease (COPD) exacerbation requiring mechanical ventilation is commonly encountered in the ICU. Sedation is necessary to facilitate mechanical ventilation. The effect of no-sedation strategy on different patient parameters on the ventilator has not yet been well studied. The aim of this study was to test the efficacy of no-sedation protocol in controlling COPD patient’s gasometric and clinical parameters during mechanical ventilation. Patients and methods Patients with COPD who required mechanical ventilation were randomized to either: sedated with daily interruption (control group) (n=50) or nonsedated group (n=47). The change in the partial pressure of arterial CO2 (PaCO2) was the primary outcome measure. Secondary outcome measures included: changes in pH, heart rate (HR), mean arterial blood pressure (MAP), respiratory rate, airway occlusion pressure (P0.1), and negative inspiratory force (NIF). Recordings for arterial blood gases, HR, MAP, and respiratory rate were performed as baseline at intubation, 1, 2, 12, 24, and 48h after intubation. NIF and P0.1 were recorded 48 h after intubation. Results No significant difference was found in baseline recordings of PaCO2, pH, HR, MAP, and respiratory rate between the sedated and nonsedated groups. Further recordings of PaCO2 (P_1, P_2, P_3, and P_4
- Published
- 2019
- Full Text
- View/download PDF
60. Green and Efficient Synthesis of Bis(indolyl)methanes in the Presence of Mesoporous acidic Nano-Ordered Catalysts under Ball Milling
- Author
-
Maryam Khayati and Mohammad G. Dekamin
- Subjects
heterogeneous catalysis ,nano-ordered solid acid ,so3h-functionalized mesoporous silica (mcm-41-so3h) ,bis(indolyl)methane compounds ,ball-milling technique ,green chemistry ,Chemistry ,QD1-999 - Abstract
In this study, a green and efficient method for the synthesis of biologically-active bis(indolyl)methane compounds (BIMs) has been described through the condensation of indole with different carbonyl compounds in the presence of SO3H-functionalized mesoporous silica materials (MCM-41-SO3H) catalyst under ball milling. Synthesis of BIMs is proceed very well in the presence of nano-ordered MCM-41-SO3H under solvent-free conditions using ball-milling technique at room temperature. The MCM-41-SO3H can be used at least four consecutive times under optimized conditions with a slight decrease in its catalytic activity. High to quantitative yields of the desired products, low loading of the catalyst, short reaction times at ambient temperature, reusability of the catalysts, and avoiding the use of toxic solvents are significant advantages of this green protocol.
- Published
- 2019
- Full Text
- View/download PDF
61. High-grade Features of Papillary Cystadenocarcinoma of the Parotid Gland
- Author
-
Kevin Y. Wang, Do H. Kim, Ya Xu, Mohammad G. Rad, and Christie M. Lincoln
- Subjects
Cystadenocarcinoma ,Papillary ,Adenocarcinoma ,Salivary Glands ,Parotid Gland ,Medicine - Abstract
Papillary cystadenocarcinomas (PCAs) are rare low-grade salivary gland tumors first introduced in the World Health Organization classification in 1991. While classically regarded as a low-grade malignancy, PCAs with more clinically and histologically high-grade features have been reported, reflecting the often-underrecognized morphological diversity of this entity. Although no universally advocated grading system exists, high-grade PCAs tend to demonstrate locally aggressive features, cytologic atypia, high mitotic rate, necrosis, and an absence of papillary features. We present a case of a 51-year-old male with slow-onset, progressive right facial fullness over four years. Contrast-enhanced computed tomography of the neck demonstrated a 3.3 cm peripherally enhancing cystic and solid mass in the right superficial lobe of the parotid gland. Following a superficial parotidectomy and a selective right neck dissection, histopathology demonstrated a large cyst with papillary projections lined with cuboidal cells of mild to moderate atypia and surrounding solid tumor nests. The tumor displayed stromal, lymphovascular, and subcutaneous fibroadipose tissue invasion. One of 12 lymph nodes was positive for metastatic carcinoma without extranodal extension. A diagnosis of intermediate-grade PCA was rendered. This case report summarizes the features typical of high-grade PCAs, the few reported cases of intermediate- and high-grade PCAs within the existing literature and provides a brief overview of the radiological and pathological differential diagnosis when considering a parotid gland PCA.
- Published
- 2019
- Full Text
- View/download PDF
62. Naturally Occurring 8ß,13ß-kaur-15-en-17-al and Anti-Malarial Activity from Podocarpus polystachyus Leaves
- Author
-
Mira Syahfriena Amir Rawa, Mohammad G. Al-Thiabat, Toshihiko Nogawa, Yushi Futamura, Akiko Okano, and Habibah A. Wahab
- Subjects
Podocarpus polystachyus ,Podocarpaceae ,kaurene ,anti-malarial ,Plasmodium falciparum ,PfLDH ,Medicine ,Pharmacy and materia medica ,RS1-441 - Abstract
Despite much interest and studies toward the genus Podocarpus, the anti-malarial evaluation of Podocarpus polystachyus’s phytoconstituents remains lacking. Herein, the phytoconstituents of P. polystachyus leaves and their anti-malarial effect against Plasmodium falciparum were investigated for the first time. One new natural product, 8ß,13ß-kaur-15-en-17-al (1), along with three known compounds, 8ß,13ß-kaur-15-en-17-ol (2) and 13ß-kaur-16-ene (3), and α-tocopherol hydroquinone (4) were isolated via HR-ESI-MS and NMR analyses. Compounds 1 and 2 inhibited P. falciparum growth at 12 and 52 µM of IC50, respectively. Their anti-malarial activity was associated with the in silico P. falciparum lactate dehydrogenase (PfLDH) inhibition. Molecular docking of ligands 1 and 2 with the putative target PfLDH revealed ~−2 kcal/mol of binding energies more negative than the control. Molecular dynamic simulations (100 ns) showed equal or smaller deviation values (RMSD, RMSF, Rg) and stronger interactions of PfLDH-1 and PfLDH-2 complexes via at least one consistent H-bond than the control. Additionally, a slightly increased PfLDH H-bond profile in their interactions improved the PfLDH dynamic and structural stabilities. Overall, this study supports the relevance of 1 and 2 as plasmodial growth inhibitors with their putative anti-PfLDH activity, which could be a potential scaffold for developing anti-malarial drugs.
- Published
- 2022
- Full Text
- View/download PDF
63. Solar Desiccant Cooling System for a Commercial Building in Kuwait’s Climatic Condition
- Author
-
Ramadas Narayanan, Abeer Abdullah Al Anazi, Roberto Pippia, and Mohammad G. Rasul
- Subjects
air conditioning ,desiccant cooling ,numerical modelling ,solar collector ,Technology - Abstract
The use of air conditioning in buildings to provide a comfortable environment accounts for up to 75% of the electricity consumed in Kuwait for the hot season from April through to the end of October. The widespread adoption of air conditioning systems in buildings has resulted in an increased demand for electricity. This has led to an increased peak load demand that has resulted in a larger carbon footprint and placed the electricity grid under significant strain. Heat-driven air conditioning systems that use solar energy are now emerging as alternatives to electricity-driven conventional refrigerated air conditioners. These systems are more energy-efficient, with lower carbon emissions while also ensuring better indoor air quality and comfort when optimally designed. Among the heat-driven air conditioning systems, the desiccant cooling system is among the systems with the most potential. This paper presents a numerical investigation of the design optimization of solar desiccant cooling systems for Kuwait’s climate. The numerical model of the system is developed using validated components. The various design configurations analysed include a solar heating system and regeneration air for the desiccant wheel. It is found that an evacuated tube solar collector in conjunction with return air from the building to regenerate the desiccant wheel provides the best results.
- Published
- 2022
- Full Text
- View/download PDF
64. Resveratrol Reduces COMPopathy in Mice Through Activation of Autophagy
- Author
-
Jacqueline T Hecht, Francoise Coustry, Alka C Veerisetty, Mohammad G Hossain, and Karen L Posey
- Subjects
DISEASES AND DISORDERS OF/RELATED TO BONE ,GENETIC ANIMAL MODELS ,GROWTH PLATE ,PRECLINICAL STUDIES ,THERAPEUTICS ,Orthopedic surgery ,RD701-811 ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
ABSTRACT Misfolding mutations in cartilage oligomeric matrix protein (COMP) cause it to be retained within the endoplasmic reticulum (ER) of chondrocytes, stimulating a multitude of damaging cellular responses including ER stress, inflammation, and oxidative stress, which ultimately culminates in the death of growth plate chondrocytes and pseudoachondroplasia (PSACH). Previously, we demonstrated that an antioxidant, resveratrol, substantially reduces the intracellular accumulation of mutant‐COMP, dampens cellular stress, and lowers the level of growth plate chondrocyte death. In addition, we showed that resveratrol reduces mammalian target of rapamycin complex 1 (mTORC1) signaling, suggesting a potential mechanism. In this work, we investigate the role of autophagy in treatment of COMPopathies. In cultured chondrocytes expressing wild‐type COMP or mutant‐COMP, resveratrol significantly increased the number of Microtubule‐associated protein 1A/1B‐light chain 3 (LC3) vesicles, directly demonstrating that resveratrol‐stimulated autophagy is an important component of the resveratrol‐driven mechanism responsible for the degradation of mutant‐COMP. Moreover, pharmacological inhibitors of autophagy suppressed degradation of mutant‐COMP in our established mouse model of PSACH. In contrast, blockage of the proteasome did not substantially alter resveratrol clearance of mutant‐COMP from growth plate chondrocytes. Mechanistically, resveratrol increased SIRT1 and PP2A expression and reduced MID1 expression and activation of phosphorylated protein kinase B (pAKT) and mTORC1 signaling in growth plate chondrocytes, allowing clearance of mutant‐COMP by autophagy. Importantly, we show that optimal reduction in growth plate pathology, including decreased mutant‐COMP retention, decreased mTORC1 signaling, and restoration of chondrocyte proliferation was attained when treatment was initiated between birth to 1 week of age in MT‐COMP mice, translating to birth to approximately 2 years of age in children with PSACH. These results clearly demonstrate that resveratrol stimulates clearance of mutant‐COMP by an autophagy‐centric mechanism. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.
- Published
- 2021
- Full Text
- View/download PDF
65. Inhibiting Freeze-Thaw Damage in Cement Paste and Concrete by Mimicking Nature’s Antifreeze
- Author
-
Shane D. Frazier, Mohammad G. Matar, Jorge Osio-Norgaard, Anastasia N. Aday, Elizabeth A. Delesky, and Wil V. Srubar, III
- Subjects
antifreeze proteins ,biomimicry ,antifreeze polymers ,ice recrystallization inhibition ,dynamic ice shaping ,cement paste ,Physics ,QC1-999 - Abstract
Summary: Since the 1930s, surfactant-based air-entraining admixtures (AEAs) have been used to mitigate freeze-thaw damage in cementitious materials. While effective, entrained air voids weaken concrete and increase its permeability, thereby increasing susceptibility to multiple other forms of in situ degradation. Inspired by nature, we report that a soluble biomimetic antifreeze polymer that displays ice recrystallization inhibition (IRI) and dynamic ice shaping (DIS) activities can prevent damage from ice crystal growth in cement paste and concrete. We first report that polyethylene glycol-graft-polyvinyl alcohol (PEG-PVA) mimics the explicit IRI and DIS activity of native ice-binding proteins in high-pH media characteristic of concrete pore solution. Second, we report that addition of PEG-PVA to cement paste and concrete prevents freeze-thaw damage without entraining air. Taken together, the findings demonstrate an alternative mechanistic approach to AEAs that can be leveraged to prevent damage from ice crystal growth in cementitious materials.
- Published
- 2020
- Full Text
- View/download PDF
66. Ion-Sensitive Field-Effect Transistors With Micropillared Gates for Measuring Cell Ion Exchange at Molecular Levels
- Author
-
Mohammad G. Abdallah, Rayan Khan, Christian Garcia, Young-Tae Kim, and Samir M. Iqbal
- Subjects
Cancer ,biological interactions ,cellular biophysics ,biochemical analysis ,diseases ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
The detection of small concentrations of cancer cells before cancer takes over the primary organ completely, or metastasizes to other areas of the body is important for early screening of cancer. One approach to address cancer early screening is through cell ion exchange bioelectricity, which characterizes voltage potential in non-neuronal cells to regulate shape changing, proliferation, differentiation, migration, and cancer formation. Herein, novel ion-sensitive field-effective transistor (ISFET) modality is shown to measure cell behavior during the change of cell properties at molecular levels. ISFETs produce low resistance signals and consume low power. The small size of ISFETs enables miniature diagnosis devices that can be affordably fabricated in a massive array format. A large number of cells can be measured in parallel. Therefore, ISFET allows the combination of low sample requirements and prompt response. ISFETs have the ability to measure the effect of ions from complex biological samples and can be used as affordable point of care devices.
- Published
- 2018
- Full Text
- View/download PDF
67. MCM-41 mesoporous silica: a highly efficient and recoverable catalyst for rapid synthesis of α-aminonitriles and imines
- Author
-
Mohammad Eslami, Mohammad G. Dekamin, Leila Motlagh, and Ali Maleki
- Subjects
MCM-41 mesoporous silica ,α-aminonitriles ,multicomponent reactions (MCRs) ,heterogeneous catalysis ,green chemistry ,Science ,Chemistry ,QD1-999 - Abstract
In this work, pure MCM-41 mesoporous silica with active mesoporous sites has been successfully applied, as a highly efficient and recoverable catalyst, for the rapid and convenient synthesis of α-aminonitriles and imines. Various imines, as the intermediate of the Strecker reaction, were simply prepared from condensation of a wide range of aldehydes and amines in the presence of low loading of MCM-41 mesoporous silica under solvent-free conditions at room temperature in high to quantitative yields. Furthermore, the corresponding α-aminonitrile derivatives were prepared through the three-component Strecker reaction using trimethylsilylcyanide catalyzed by MCM-41 as a bifunctional heterogeneous mesoporous solid catalyst.
- Published
- 2018
- Full Text
- View/download PDF
68. An improved solvent-free synthesis of flunixin and 2-(arylamino) nicotinic acid derivatives using boric acid as catalyst
- Author
-
Mahsa Yarhosseini, Shahrzad Javanshir, Zahra Dolatkhah, and Mohammad G. Dekamin
- Subjects
Homogeneous catalysis ,Solvent-free ,Non-steroidal anti-inflammatory drugs (NSAID) ,N-Methyl-d-glucamine ,Boric acid ,Anilino-nicotinic acid ,Chemistry ,QD1-999 - Abstract
Abstract A simple solvent-free protocol for the preparation of flunixin, a potent non-narcotic, non-steroidal anti-inflammatory drugs is reported using boric acid as catalyst. Its salt, flunixin meglumine are then prepared under reflux in EtOH. This sustainable method are then extended for the synthesis of a series of 2-(arylamino) nicotinic acid derivatives. The present protocol combines non-hazardous neat conditions with associated benefits like excellent yield, straightforward workup, and use of readily available and safe catalyst in the absence of any solvent, which are important factors in the pharmaceutical industry. The pathway for catalytic activation of 2-chloronicotic acid with boric acid was also investigated using Gaussian 03 program package.
- Published
- 2017
- Full Text
- View/download PDF
69. Unraveling the Butterfly Effects in Social Dynamics: Insights from Agent-Based Modeling
- Author
-
Sabzian, Hossein, Shahriari, Nima, and Nejad, Mohammad G.
- Subjects
Physics - Physics and Society - Abstract
The complex interplay between human societies and their environments has long been a subject of fascination for social scientists. Utilizing agent-based modeling, this study delves into the profound implications of seemingly inconsequential variations in social dynamics. Focusing on the nexus between food distribution, residential patterns, and population dynamics, our research provides an analysis of the long-term implications of minute societal changes over the span of 300 years. Through a meticulous exploration of two scenarios, we uncover the profound impact of the butterfly effect on the evolution of human societies, revealing the fact that even the slightest perturbations in the distribution of resources can catalyze monumental shifts in residential patterns and population trajectories. This research sheds light on the inherent complexity of social systems and underscores the sensitivity of these systems to subtle changes, emphasizing the unpredictable nature of long-term societal trajectories. The implications of our findings extend far beyond the realm of social science, carrying profound significance for policy-making, sustainable development, and the preservation of societal equilibrium in an ever-changing world., Comment: 14 pages, 4 Figures, 2 Tables
- Published
- 2023
70. Joint Degeneration in a Mouse Model of Pseudoachondroplasia: ER Stress, Inflammation, and Block of Autophagy
- Author
-
Jacqueline T. Hecht, Alka C. Veerisetty, Mohammad G. Hossain, Debabrata Patra, Frankie Chiu, Francoise Coustry, and Karen L. Posey
- Subjects
cartilage oligomeric matrix protein ,pseudoachondroplasia ,autophagy ,ER stress ,dwarfism ,chondrocyte ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Pseudoachondroplasia (PSACH), a short limb skeletal dysplasia associated with premature joint degeneration, is caused by misfolding mutations in cartilage oligomeric matrix protein (COMP). Here, we define mutant-COMP-induced stress mechanisms that occur in articular chondrocytes of MT-COMP mice, a murine model of PSACH. The accumulation of mutant-COMP in the ER occurred early in MT-COMP articular chondrocytes and stimulated inflammation (TNFα) at 4 weeks, and articular chondrocyte death increased at 8 weeks while ER stress through CHOP was elevated by 12 weeks. Importantly, blockage of autophagy (pS6), the major mechanism that clears the ER, sustained cellular stress in MT-COMP articular chondrocytes. Degeneration of MT-COMP articular cartilage was similar to that observed in PSACH and was associated with increased MMPs, a family of degradative enzymes. Moreover, chronic cellular stresses stimulated senescence. Senescence-associated secretory phenotype (SASP) may play a role in generating and propagating a pro-degradative environment in the MT-COMP murine joint. The loss of CHOP or resveratrol treatment from birth preserved joint health in MT-COMP mice. Taken together, these results indicate that ER stress/CHOP signaling and autophagy blockage are central to mutant-COMP joint degeneration, and MT-COMP mice joint health can be preserved by decreasing articular chondrocyte stress. Future joint sparing therapeutics for PSACH may include resveratrol.
- Published
- 2021
- Full Text
- View/download PDF
71. Conjugated β-Cyclodextrin Enhances the Affinity of Folic Acid towards FRα: Molecular Dynamics Study
- Author
-
Mohammad G. Al-Thiabat, Amirah Mohd Gazzali, Noratiqah Mohtar, Vikneswaran Murugaiyah, Ezatul Ezleen Kamarulzaman, Beow Keat Yap, Noorsaadah Abd Rahman, Rozana Othman, and Habibah A. Wahab
- Subjects
targeted drug delivery system ,folate receptor alpha ,folic acid-conjugated cyclodextrins ,molecular docking ,molecular dynamics ,radius of gyration (Rg) ,Organic chemistry ,QD241-441 - Abstract
Drug targeting is a progressive area of research with folate receptor alpha (FRα) receiving significant attention as a biological marker in cancer drug delivery. The binding affinity of folic acid (FA) to the FRα active site provides a basis for recognition of FRα. In this study, FA was conjugated to beta-cyclodextrin (βCD) and subjected to in silico analysis (molecular docking and molecular dynamics (MD) simulation (100 ns)) to investigate the affinity and stability for the conjugated system compared to unconjugated and apo systems (ligand free). Docking studies revealed that the conjugated FA bound into the active site of FRα with a docking score (free binding energy < −15 kcal/mol), with a similar binding pose to that of unconjugated FA. Subsequent analyses from molecular dynamics (MD) simulations, root mean square deviation (RMSD), root mean square fluctuation (RMSF), and radius of gyration (Rg) demonstrated that FA and FA–βCDs created more dynamically stable systems with FRα than the apo-FRα system. All systems reached equilibrium with stable RMSD values ranging from 1.9–2.4 Å and the average residual fluctuation values of the FRα backbone atoms for all residues (except for terminal residues ARG8, THR9, THR214, and LEU215) were less than 2.1 Å with a consistent Rg value of around 16.8 Å throughout the MD simulation time (0–100 ns). The conjugation with βCD improved the stability and decreased the mobility of all the residues (except residues 149–151) compared to FA–FRα and apo-FRα systems. Further analysis of H-bonds, binding free energy (MM-PBSA), and per residue decomposition energy revealed that besides APS81, residues HIS20, TRP102, HIS135, TRP138, TRP140, and TRP171 were shown to have more favourable energy contributions in the holo systems than in the apo-FRα system, and these residues might have a direct role in increasing the stability of holo systems.
- Published
- 2021
- Full Text
- View/download PDF
72. A Review on the Thermochemical Recycling of Waste Tyres to Oil for Automobile Engine Application
- Author
-
Mohammad I. Jahirul, Farhad M. Hossain, Mohammad G. Rasul, and Ashfaque Ahmed Chowdhury
- Subjects
waste tyre ,waste management ,pyrolysis ,automobile engine ,Technology - Abstract
Utilising pyrolysis as a waste tyre processing technology has various economic and social advantages, along with the fact that it is an effective conversion method. Despite extensive research and a notable likelihood of success, this technology has not yet seen implementation in industrial and commercial settings. In this review, over 100 recent publications are reviewed and summarised to give attention to the current state of global tyre waste management, pyrolysis technology, and plastic waste conversion into liquid fuel. The study also investigated the suitability of pyrolysis oil for use in diesel engines and provided the results on diesel engine performance and emission characteristics. Most studies show that discarded tyres can yield 40–60% liquid oil with a calorific value of more than 40 MJ/kg, indicating that they are appropriate for direct use as boiler and furnace fuel. It has a low cetane index, as well as high viscosity, density, and aromatic content. According to diesel engine performance and emission studies, the power output and combustion efficiency of tyre pyrolysis oil are equivalent to diesel fuel, but engine emissions (NOX, CO, CO, SOX, and HC) are significantly greater in most circumstances. These findings indicate that tyre pyrolysis oil is not suitable for direct use in commercial automobile engines, but it can be utilised as a fuel additive or combined with other fuels.
- Published
- 2021
- Full Text
- View/download PDF
73. The Isocyanurate-Carbamate-Bridged Hybrid Mesoporous Organosilica: An Exceptional Anchor for Pd Nanoparticles and a Unique Catalyst for Nitroaromatics Reduction
- Author
-
Ali Zebardasti, Mohammad G. Dekamin, and Esmail Doustkhah
- Subjects
hybrid mesoporous silica ,Pd nanoparticles ,p-nitrophenol ,reduction ,heterogeneous catalyst ,PMO ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
Hybridisation of mesoporous organosilicas (MO) to reinforce the surface capability in adsorption and stabilisation of noble metal nanoparticles is of great attention in generating/supporting noble metal within their matrices and transforming them into efficient heterogeneous catalysts. Here, we used a unique hybrid of organic-inorganic mesoporous silica in which pore profile pattern was similar to the well-known mesoporous silica, SBA-15 for catalysis. This hybrid mesoporous organosilica was further engaged as a support in the synthesis and stabilisation of Pd nanoparticles on its surface, and then, the obtained Pd-supported MO was employed as a heterogeneous green catalyst in the conversion of aqueous p-nitrophenol (PNP) to p-aminophenol (PAP) at room temperature with efficient recyclability.
- Published
- 2021
- Full Text
- View/download PDF
74. A facile and environmentally benign polyethylene glycol 600-mediated method for the synthesis of densely functionalized 2-aminothiophene derivatives under ultrasonication
- Author
-
Ali Akbarzadeh and Mohammad G. Dekamin
- Subjects
2-aminothiophenes ,gewald reaction ,polyethylene glycol (PEG) 600 ,multicomponent reactions (MCRs) ,ultrasound irradiation ,Science ,Chemistry ,QD1-999 - Abstract
A green and efficient protocol for the synthesis of densely functionalized 2-aminothiophene derivatives is described by the one-pot three-component Gewald reaction from enolizable carbonyl compounds, malononitrile (or ethyl cyanoacetate) and elemental sulfur in polyethylene glycol 600, as an eco-friendly reaction medium, without using any basic compounds under ultrasonic be recovered and reused at least five times without significant loss of its activity. The merits of this protocol are mild reaction conditions, good yields, short reaction time, simple work-up procedure and recyclability of the reaction medium as well as avoiding the use of any basic catalyst at ambient temperature.
- Published
- 2017
- Full Text
- View/download PDF
75. Heterocyclic Substitutions Greatly Improve Affinity and Stability of Folic Acid towards FRα. an In Silico Insight
- Author
-
Mohammad G. Al-Thiabat, Fadi G. Saqallah, Amirah Mohd Gazzali, Noratiqah Mohtar, Beow Keat Yap, Yee Siew Choong, and Habibah A Wahab
- Subjects
folate receptor alpha ,folic acid and antifolates ,molecular docking ,molecular dynamics ,MM-PBSA ,H-bonds ,Organic chemistry ,QD241-441 - Abstract
Folate receptor alpha (FRα) is known as a biological marker for many cancers due to its overexpression in cancerous epithelial tissue. The folic acid (FA) binding affinity to the FRα active site provides a basis for designing more specific targets for FRα. Heterocyclic rings have been shown to interact with many receptors and are important to the metabolism and biological processes within the body. Nineteen FA analogs with substitution with various heterocyclic rings were designed to have higher affinity toward FRα. Molecular docking was used to study the binding affinity of designed analogs compared to FA, methotrexate (MTX), and pemetrexed (PTX). Out of 19 FA analogs, analogs with a tetrazole ring (FOL03) and benzothiophene ring (FOL08) showed the most negative binding energy and were able to interact with ASP81 and SER174 through hydrogen bonds and hydrophobic interactions with amino acids of the active site. Hence, 100 ns molecular dynamics (MD) simulations were carried out for FOL03, FOL08 compared to FA, MTX, and PTX. The root mean square deviation (RMSD) and root mean square fluctuation (RMSF) of FOL03 and FOL08 showed an apparent convergence similar to that of FA, and both of them entered the binding pocket (active site) from the pteridine part, while the glutamic part was stuck at the FRα pocket entrance during the MD simulations. Molecular mechanics Poisson-Boltzmann surface accessible (MM-PBSA) and H-bond analysis revealed that FOL03 and FOL08 created more negative free binding and electrostatic energy compared to FA and PTX, and both formed stronger H-bond interactions with ASP81 than FA with excellent H-bond profiles that led them to become bound tightly in the pocket. In addition, pocket volume calculations showed that the volumes of active site for FOL03 and FOL08 inside the FRα pocket were smaller than the FA–FRα system, indicating strong interactions between the protein active site residues with these new FA analogs compared to FA during the MD simulations.
- Published
- 2021
- Full Text
- View/download PDF
76. Elevated blood plasma levels of epinephrine, norepinephrine, tyrosine hydroxylase, TGFβ1, and TNFα associated with high-altitude pulmonary edema in Indian population
- Author
-
Pandey P, Ali Z, Mohammad G, and Pasha MAQ
- Subjects
Adaptation ,Biomarkers ,Correlation ,HAPE ,High altitude ,Sympathetic nervous system ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Priyanka Pandey,1,2 Zahara Ali,1,2 Ghulam Mohammad,3 MA Qadar Pasha1,2 1Functional Genomics Unit, CSIR-Institute of Genomics and Integrative Biology, Delhi, 2Department of Biotechnology, Savitribai Phule Pune University, Pune, 3Department of Medicine, SNM Hospital, Ladakh, Jammu and Kashmir, India Abstract: Biomarkers are essential to unravel the locked pathophysiology of any disease. This study investigated the role of biomarkers and their interactions with each other and with the clinical parameters to study the physiology of high-altitude pulmonary edema (HAPE) in HAPE-patients (HAPE-p) against adapted highlanders (HLs) and healthy sojourners, HAPE-controls (HAPE-c). For this, seven circulatory biomarkers, namely, epinephrine, norepinephrine, tyrosine hydroxylase, transforming growth factor beta 1, tumor necrosis factor alpha (TNFα), platelet-derived growth factor beta beta, and C-reactive protein (CRP), were measured in blood plasma of the three study groups. All the subjects were recruited at ~3,500 m, and clinical features such as arterial oxygen saturation (SaO2), body mass index, and mean arterial pressure were measured. Increased levels of epinephrine, norepinephrine, tyrosine hydroxylase, transforming growth factor-beta 1, and TNFα were observed in HAPE-p against the healthy groups, HAPE-c, and HLs (P0.01). Correlation analysis revealed a negative correlation between epinephrine and norepinephrine (P=4.6E-06) in HAPE-p and positive correlation in HAPE-c (P=0.004) and HLs (P=9.78E-07). A positive correlation was observed between TNFα and CRP (P=0.004) in HAPE-p and a negative correlation in HAPE-c (P=4.6E-06). SaO2 correlated negatively with platelet-derived growth factor beta beta (HAPE-p; P=0.05), norepinephrine (P=0.01), and TNFα (P=0.005) and positively with CRP (HAPE-c; P=0.02) and norepinephrine (HLs; P=0.04). Body mass index correlated negatively with epinephrine (HAPE-p; P=0.001) and positively with norepinephrine and tyrosine hydroxylase in HAPE-c (P0.70, P
- Published
- 2016
77. The Effect of Substrate Temperature on the Structural Properties of Spray Pyrolysed Lead Sulphide (PbS) Thin Films
- Author
-
Mohammad G. Faraj and Halo D. Omar
- Subjects
chemical spray pyrolysis, lead sulphide, semiconductor, thin film ,Technology ,Science - Abstract
Lead sulphide (PbS) films were prepared by the chemical spray pyrolysis technique using a solution of Lead nitrate and thiourea. PbS films were deposited (prepared) on glass substrate at varied temperature (250-350 oC). Effects of substrate temperature on the structural characteristics of the films were studied. The X-ray diffraction patterns’ results reveal that the all of PbS films have a face centered cubic structure. The X-ray diffraction study showed that irrespective of substrate temperature all the films exhibits a preferred orientation along the (200) plane. The degree of preferred orientation increased with the substrate temperature. It was observed that the increase of the substrate temperature increase the diffraction peak intensity of (200) plane which resulted in increase in grain size and good crystallinity of the films.
- Published
- 2016
- Full Text
- View/download PDF
78. Dlc1 interaction with non-muscle myosin heavy chain II-A (Myh9) and Rac1 activation
- Author
-
Mohammad G. Sabbir, Rachelle Dillon, and Michael R. A. Mowat
- Subjects
Dlc1 ,Non-muscle myosin ,Spectrin ,Plectin ,Rac1 ,RhoA ,Science ,Biology (General) ,QH301-705.5 - Abstract
The Deleted in liver cancer 1 (Dlc1) gene codes for a Rho GTPase-activating protein that also acts as a tumour suppressor gene. Several studies have consistently found that overexpression leads to excessive cell elongation, cytoskeleton changes and subsequent cell death. However, none of these studies have been able to satisfactorily explain the Dlc1-induced cell morphological phenotypes and the function of the different Dlc1 isoforms. Therefore, we have studied the interacting proteins associated with the three major Dlc1 transcriptional isoforms using a mass spectrometric approach in Dlc1 overexpressing cells. We have found and validated novel interacting partners in constitutive Dlc1-expressing cells. Our study has shown that Dlc1 interacts with non-muscle myosin heavy chain II-A (Myh9), plectin and spectrin proteins in different multiprotein complexes. Overexpression of Dlc1 led to increased phosphorylation of Myh9 protein and activation of Rac1 GTPase. These data support a role for Dlc1 in induced cell elongation morphology and provide some molecular targets for further analysis of this phenotype.
- Published
- 2016
- Full Text
- View/download PDF
79. Organocatalytic clean synthesis of densely functionalized 4H-pyrans by bifunctional tetraethylammonium 2-(carbamoyl)benzoate using ball milling technique under mild conditions
- Author
-
Mohammad G. Dekamin, Mohammad Alikhani, and Shahrzad Javanshir
- Subjects
Tetraethylammonium 2-(carbamoyl)benzoate ,organocatalysis ,green chemistry ,4H-pyrans ,multicomponent reactions ,Science ,Chemistry ,QD1-999 - Abstract
A green and simple method has been developed for efficient preparation of diverse annulated 2-amino-3-cyano-4H-pyran derivatives in the presence of a low loading of tetraethylammonium 2-(carbamoyl)benzoate (TEACB), as a bifunctional organocatalyst, under solvent-free conditions using the ball milling technique. This procedure is a clean, transition-metal-free, and environmentally friendly approach that offers many advantages including short reaction times, high to quantitative yields, low cost, and straightforward work-up.
- Published
- 2016
- Full Text
- View/download PDF
80. ROCK2 and MYLK variants under hypobaric hypoxic environment of high altitude associate with high altitude pulmonary edema and adaptation
- Author
-
Pandey P, Mohammad G, Singh Y, and Qadar Pasha MA
- Subjects
Medicine (General) ,R5-920 ,Genetics ,QH426-470 - Abstract
Priyanka Pandey,1,2 Ghulam Mohammad,1,3 Yogendra Singh,1,2 MA Qadar Pasha1,2 1Functional Genomics Unit, CSIR-Institute of Genomics and Integrative Biology, Delhi, 2Department of Biotechnology, University of Pune, Ganeshkhind, Pune, Maharashtra, 3Department of Medicine, SNM Hospital, Leh, Ladakh, Jammu and Kashmir, IndiaObjective: To date, a major class of kinases, serine–threonine kinase, has been scantly investigated in stress-induced rare, fatal (if not treated early), and morbid disorder, high altitude pulmonary edema (HAPE). This study examined three major serine–threonine kinases, ROCK2, MYLK, and JNK1, along with six other genes, tyrosine hydroxylase, G-protein subunits GNA11 and GNB3, and alpha1 adrenergic receptor isoforms 1A, 1B, and 1D as candidate gene markers of HAPE and adaptation.Methods: For this, 57 variants across these nine genes were genotyped in HAPE patients (n=225), HAPE controls (n=210), and highlanders (n=259) by Sequenom MS (TOF)-based MassARRAY® platform using iPLEX™ Gold technology. In addition, to study the gene expression, quantitative real-time polymerase chain reaction was performed in human peripheral blood mononuclear cells of the three study groups.Results: A significant association was observed for C allele (ROCK2 single-nucleotide polymorphism, rs10929728) with HAPE (P=0.03) and C, T, and A alleles (MYLK single-nucleotide polymorphisms, rs11717814, rs40305, and rs820336) with both HAPE and adaptation (P=0.001, P=0.006, and P=0.02, respectively). ROCK2 88 kb GGGTTGGT haplotype was associated with lower risk of HAPE (P=0.0009). MYLK 7 kb haplotype CTA, composed of variant alleles, was associated with higher risk of HAPE (P=0.0006) and lower association with adaptation (P=1E–06), whereas haplotype GCG, composed of wild-type alleles, was associated with lower risk of HAPE (P=0.001) and higher association with adaptation (P=1E–06). Haplotype–haplotype and gene–gene interactions demonstrated a correlation in working of ROCK2 and MYLK.Conclusion: The data suggest the association of ROCK2 with HAPE and MYLK with HAPE and adaptation in Indian population. The outcome has provided new insights into the physiology of HAPE and adaptation. Keywords: adaptation, hypobaric hypoxia, ROCK2, MYLK, high altitude pulmonary edema, SNP
- Published
- 2015
81. Loss of miR-101-3p Promotes Transmigration of Metastatic Breast Cancer Cells through the Brain Endothelium by Inducing COX-2/MMP1 Signaling
- Author
-
Rania Harati, Mohammad G. Mohammad, Abdelaziz Tlili, Raafat A. El-Awady, and Rifat Hamoudi
- Subjects
micro-RNA ,breast cancer ,brain metastasis ,blood–brain barrier ,Medicine ,Pharmacy and materia medica ,RS1-441 - Abstract
Brain metastases represent one of the incurable end stages in breast cancer (BC). Developing effective or preventive treatments is hampered by a lack of knowledge on the molecular mechanisms driving brain metastasis. Transmigration of BC cells through the brain endothelium is a key event in the pathogenesis of brain metastasis. In this study, we identified miR-101-3p as a critical micro-RNA able to reduce transmigration of BC cells through the brain endothelium. Our results revealed that miR-101-3p expression is downregulated in brain metastatic BC cells compared to less invasive variants, and varies inversely compared to the brain metastatic propensity of BC cells. Using a loss-and-gain of function approach, we found that miR-101-3p downregulation increased transmigration of BC cells through the brain endothelium in vitro by inducing COX-2 expression in cancer cells, whereas ectopic restoration of miR-101-3p exerted a metastasis-reducing effect. In regulatory experiments, we found that miR-101-3p mediated its effect by modulating COX-2-MMP1 signaling capable of degrading the inter-endothelial junctions (claudin-5 and VE-cadherin), key components of the brain endothelium. These findings suggest that miR-101-3p plays a critical role in the transmigration of breast cancer cells through the brain endothelium by modulating the COX-2-MMP1 signaling and thus may serve as a therapeutic target that can be exploited to prevent or suppress brain metastasis in human breast cancer.
- Published
- 2020
- Full Text
- View/download PDF
82. CFD Simulation and a Pragmatic Analysis of Performance and Emissions of Tomato Seed Biodiesel Blends in a 4-Cylinder Diesel Engine
- Author
-
Rahim Karami, Mohammad G. Rasul, and Mohammad M. K. Khan
- Subjects
AVL FIRE ,biodiesel ,CFD simulation ,emissions ,performance ,tomato ,Technology - Abstract
Rising global concerns about global warming caused by pollution from excessive fossil fuels consumption, along with the high price of them in diesel engines, are the important reasons to search for fuels which is readily available and do not have destructive effects on the environment. Biodiesel is arguably the most appropriate and sustainable alternative to diesel fuel. Tomato seeds are one of the potential sources of biodiesel. They make up about 72% by weight of tomato waste, which contains an average of 24% oil. Tomato seed oil (TSO) can be used as a cheap and non-edible source of biodiesel. This paper investigated, both experimentally and numerically, the effects of different diesel–TSOB (tomato seed oil biodiesel) blends on the performance and emissions parameters of a four-cylinder, four-stroke, indirect injection diesel engine. The main goal of the paper was the simulation of the formation process of the emissions in the combustion chamber. The experimentally measured parameters such as torque, brake specific fuel consumption, exhaust gas temperature, nitrogen oxides, carbon monoxide, carbon dioxide, particulate matter, peak in-cylinder pressure, in-cylinder temperature and Reaction_Progress_Variable at different engine loads and speeds from 1200 to 2400 rpm at increments of 200 rpm are analyzed through ANOVA. The highest brake specific fuel consumption (BSFC) was observed for pure diesel and the lowest for the fuel blend with 10% biodiesel. The fuel blend with 20% biodiesel produced the highest torque. The engine was modeled using the AVL FIRE software. The model simulation results revealed that the highest nitrogen oxide (NOx) is produced in the throat of the combustion chamber to the top of the piston, the place of carbon dioxides (CO2) formation is near the combustion chamber boundaries and the location of carbon monoxides (CO) formation is near the combustion chamber boundaries and at the center area of the top of the piston. These results also show that the particulate matter (PM) emissions are formed where the fuel is injected into the combustion chamber.
- Published
- 2020
- Full Text
- View/download PDF
83. The Role of Lipid Metabolism in COVID-19 Virus Infection and as a Drug Target
- Author
-
Mohamed Abu-Farha, Thangavel Alphonse Thanaraj, Mohammad G. Qaddoumi, Anwar Hashem, Jehad Abubaker, and Fahd Al-Mulla
- Subjects
coronavirus ,COVID-19 ,SARS-COV-2 ,lipid metabolism ,sphingolipid ,endocytosis ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The current Coronavirus disease 2019 or COVID-19 pandemic has infected over two million people and resulted in the death of over one hundred thousand people at the time of writing this review. The disease is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Even though multiple vaccines and treatments are under development so far, the disease is only slowing down under extreme social distancing measures that are difficult to maintain. SARS-COV-2 is an enveloped virus that is surrounded by a lipid bilayer. Lipids are fundamental cell components that play various biological roles ranging from being a structural building block to a signaling molecule as well as a central energy store. The role lipids play in viral infection involves the fusion of the viral membrane to the host cell, viral replication, and viral endocytosis and exocytosis. Since lipids play a crucial function in the viral life cycle, we asked whether drugs targeting lipid metabolism, such as statins, can be utilized against SARS-CoV-2 and other viruses. In this review, we discuss the role of lipid metabolism in viral infection as well as the possibility of targeting lipid metabolism to interfere with the viral life cycle.
- Published
- 2020
- Full Text
- View/download PDF
84. Performance, Emission and Combustion Characteristics of a Diesel Engine Powered by Macadamia and Grapeseed Biodiesels
- Author
-
Abul Kalam Azad, Julian Adhikari, Pobitra Halder, Mohammad G. Rasul, Nur M. S. Hassan, Mohammad M. K. Khan, Salman Raza Naqvi, and Karthickeyan Viswanathan
- Subjects
biodiesel ,macadamia biodiesel ,grapeseed biodiesel ,brake specific fuel consumption ,brake thermal efficiency ,CO ,Technology - Abstract
Biodiesel is an alternative, eco-friendly and renewable source of energy. It can be produced from a wide range of feedstocks which can be grown in marginal land use. It has drawn more attention to the researchers. In this study, the oil extraction, biodiesel conversion, and physiochemical properties of Macadamia (Macadamia integrifolia) and Grapeseed (Vitis vinifera) biodiesels are presented. The experimental investigation of diesel engine performance, emissions and combustion characteristics were conducted using B5 (5% biodiesel and 95% diesel by volume) and B10 (10% biodiesel and 90% diesel by volume) blends. The engine performance parameters, such as brake power (BP), brake specific fuel consumption (BSFC), and brake thermal efficiency (BTE) have been investigated in this experiment. The emission parameters, for example, carbon monoxide (CO), the ratio of CO2/CO, nitrogen oxide (NOx), hydrocarbon (HC), particulate matter (PM) have been measured during the experiment. Finally, the combustion parameters such as cylinder pressure (CP) were recorded, and heat release rate (HRR) was analysed and compared with that of diesel fuel. The study revealed that the Macadamia biodiesel performed better than Grapeseed biodiesel and behaved closely to that of diesel fuel. A significant reduction of engine emissions was found in the case of Macadamia biodiesel with a minimal reduction of engine performance. Further analysis of energy, exergy and tribological characteristics of the Macadamia biodiesel is recommended for assessing its feasibility for commercial application.
- Published
- 2020
- Full Text
- View/download PDF
85. Quantification of Neuropeptide Y with Picomolar Sensitivity Enabled by Guided-Mode Resonance Biosensors
- Author
-
Mohammad G. Abdallah, Joseph A. Buchanan-Vega, Kyu J. Lee, Brett R. Wenner, Jeffery W. Allen, Monica S. Allen, Susanne Gimlin, Debra Wawro Weidanz, and Robert Magnusson
- Subjects
biomarkers ,guided-mode resonance biosensor ,neuropeptide y ,optical biosensor ,sandwich assay ,Chemical technology ,TP1-1185 - Abstract
Assessing levels of neuropeptide Y (NPY) in the human body has many medical uses. Accordingly, we report the quantitative detection of NPY biomarkers applying guided-mode resonance (GMR) biosensor methodology. The label-free sensor operates in the near-infrared spectral region exhibiting distinctive resonance signatures. The interaction of NPY with bioselective molecules on the sensor surface causes spectral shifts that directly identify the binding event without additional processing. In the experiments described here, NPY antibodies are attached to the sensor surface to impart specificity during operation. For the low concentrations of NPY of interest, we apply a sandwich NPY assay in which the sensor-linked anti-NPY molecule binds with NPY that subsequently binds with anti-NPY to close the sandwich. The sandwich assay achieves a detection limit of ~0.1 pM NPY. The photonic sensor methodology applied here enables expeditious high-throughput data acquisition with high sensitivity and specificity. The entire bioreaction is recorded as a function of time, in contrast to label-based methods with single-point detection. The convenient methodology and results reported are significant, as the NPY detection range of 0.1−10 pM demonstrated is useful in important medical circumstances.
- Published
- 2019
- Full Text
- View/download PDF
86. Performance Analysis of Direct Injection Diesel Engine Fueled with Diesel-Tomato Seed Oil Biodiesel Blending by ANOVA and ANN
- Author
-
Rahim Karami, Mohammad G. Rasul, Mohammad M. K. Khan, and Mohammad Anwar
- Subjects
tomato seeds ,biodiesel ,engine performance ,ann ,anova ,Technology - Abstract
Biodiesel is an alternative fuel for diesel engine. Considering the differences between diesel and biodiesel fuels, the engine condition should be modified based on the fuel or fuel blends to achieve optimum performance. This study presented a performance analysis of a direct-injected (DI) diesel engine with a dynamometer fueled with diesel-tomato seed biodiesel (TSOB) blends employing ANOVA and universal nonlinear model based on ANN. The experiments were carried out under conditions of some independent variables including different engine loads (0, 50, 100%) and speed (1800, 2150, and 2500 rpm) for four diesel-biodiesel combinations (B0, B5, B10, and B20). In this research, the effect of these factors on dependent variables including power, torque, SFC, FC, and Exhaust Gas Temperature (EGT) are investigated. Duncan′s multi-domain test at a significance level of R < 0.01 shows that the highest and lowest of the torque and power are produced from B5 and B20, respectively. These results show that the lowest EGT of 613 K is related to B20 and the highest EGT is related to B5 and B10. The regression models showed that the torque decreases with increasing the engine speed and biodiesel percentage. These results also show that the highest and the lowest SFC is related to B0 and B20, respectively. The ANN model shows high capability of predicting the engine performance parameters and emissions, without running costly and time-consuming experiments with the histogram error of 0.004 and R = 0.96. It also proved that ANN is a non-linear model of choice to deal with these data, instead of multivariate linear regression employed for preliminary analysis.
- Published
- 2019
- Full Text
- View/download PDF
87. Muscarinic Acetylcholine Type 1 Receptor Activity Constrains Neurite Outgrowth by Inhibiting Microtubule Polymerization and Mitochondrial Trafficking in Adult Sensory Neurons
- Author
-
Mohammad G. Sabbir, Nigel A. Calcutt, and Paul Fernyhough
- Subjects
muscarinic receptors ,mitochondria ,antagonist ,G proteins ,cytoskeleton dynamics ,mitochondrial trafficking ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
The muscarinic acetylcholine type 1 receptor (M1R) is a metabotropic G protein-coupled receptor. Knockout of M1R or exposure to selective or specific receptor antagonists elevates neurite outgrowth in adult sensory neurons and is therapeutic in diverse models of peripheral neuropathy. We tested the hypothesis that endogenous M1R activation constrained neurite outgrowth via a negative impact on the cytoskeleton and subsequent mitochondrial trafficking. We overexpressed M1R in primary cultures of adult rat sensory neurons and cell lines and studied the physiological and molecular consequences related to regulation of cytoskeletal/mitochondrial dynamics and neurite outgrowth. In adult primary neurons, overexpression of M1R caused disruption of the tubulin, but not actin, cytoskeleton and significantly reduced neurite outgrowth. Over-expression of a M1R-DREADD mutant comparatively increased neurite outgrowth suggesting that acetylcholine released from cultured neurons interacts with M1R to suppress neurite outgrowth. M1R-dependent constraint on neurite outgrowth was removed by selective (pirenzepine) or specific (muscarinic toxin 7) M1R antagonists. M1R-dependent disruption of the cytoskeleton also diminished mitochondrial abundance and trafficking in distal neurites, a disorder that was also rescued by pirenzepine or muscarinic toxin 7. M1R activation modulated cytoskeletal dynamics through activation of the G protein (Gα13) that inhibited tubulin polymerization and thus reduced neurite outgrowth. Our study provides a novel mechanism of M1R control of Gα13 protein-dependent modulation of the tubulin cytoskeleton, mitochondrial trafficking and neurite outgrowth in axons of adult sensory neurons. This novel pathway could be harnessed to treat dying-back neuropathies since anti-muscarinic drugs are currently utilized for other clinical conditions.
- Published
- 2018
- Full Text
- View/download PDF
88. Mechanical and phytochemical protection mechanisms of Calligonum comosum in arid deserts.
- Author
-
Sameh Soliman, Mohammad G Mohammad, Ali A El-Keblawy, Hany Omar, Mohamed Abouleish, Mohamed Madkour, Attiat Elnaggar, and Racha M Hosni
- Subjects
Medicine ,Science - Abstract
Unlike animals, plants are sessile organisms, lacking circulating antibodies and specialized immune cells and are exposed to various harsh environmental conditions that make them at risk of being attacked by different pathogens and herbivores. Plants produce chemo-signals to respond to the surroundings and be able to distinguish between harmless and harmful signals. In this study, the production of phytochemicals as plant signaling mechanisms and their defensive roles in disease resistance and repelling herbivores are examined in Calligonum comosum. C. comosum is a leafless standalone perennial shrub widespread in sand dunes. The plant has the ability to survive the drastic environmental conditions of the arid/ hyperarid deserts of the Arabia. Structural anatomy and phytochemicals analyses were used to identify both mechanical and chemical defensive mechanisms in C. comosum. Microscopy-based investigations indicated that stems of this species developed hard structures in its outer layers including sclerenchyma and cluster crystals of calcium oxalate (CaOx). Sclerenchyma and CaOx are difficult to be eaten by herbivores and insects and can harm their mouthparts. On the other hand, the plant developed both short-distance (local) and long-distance (systematic over limited sphere) phytochemicals-producing cells located at its outer regions that is surrounding the inner nutrient-rich vascular system (VS). Local chemical was represented by phenolic idioblasts that were released in response to plant cutting. Systematic chemical was represented by toxic volatile oil containing ~50% benzaldehyde derivative (cuminaldehyde). The oil caused strong killing effect on both mammalian cells and microbial pathogens via either direct addition or indirect exposure to its vapor. The plants lost the oil content and allowed fungal growth once cut and dried. The localization of both defensive mechanisms to the outer region of the plant seemed to protect the inner nutrient-rich VS and hence maintained the plant survival. Surprisingly, in relation to traditional folklore use as medicine, local people use only green parts of the plant and only during the winter, where the plant found devoid of volatile oil and phenolic idioblasts. Moreover, it turns into recommendations for local people to avoid any health problems caused by the plant supply.
- Published
- 2018
- Full Text
- View/download PDF
89. Optimum strata boundaries and sample sizes in health surveys using auxiliary variables.
- Author
-
Karuna Garan Reddy, Mohammad G M Khan, and Sabiha Khan
- Subjects
Medicine ,Science - Abstract
Using convenient stratification criteria such as geographical regions or other natural conditions like age, gender, etc., is not beneficial in order to maximize the precision of the estimates of variables of interest. Thus, one has to look for an efficient stratification design to divide the whole population into homogeneous strata that achieves higher precision in the estimation. In this paper, a procedure for determining Optimum Stratum Boundaries (OSB) and Optimum Sample Sizes (OSS) for each stratum of a variable of interest in health surveys is developed. The determination of OSB and OSS based on the study variable is not feasible in practice since the study variable is not available prior to the survey. Since many variables in health surveys are generally skewed, the proposed technique considers the readily-available auxiliary variables to determine the OSB and OSS. This stratification problem is formulated into a Mathematical Programming Problem (MPP) that seeks minimization of the variance of the estimated population parameter under Neyman allocation. It is then solved for the OSB by using a dynamic programming (DP) technique. A numerical example with a real data set of a population, aiming to estimate the Haemoglobin content in women in a national Iron Deficiency Anaemia survey, is presented to illustrate the procedure developed in this paper. Upon comparisons with other methods available in literature, results reveal that the proposed approach yields a substantial gain in efficiency over the other methods. A simulation study also reveals similar results.
- Published
- 2018
- Full Text
- View/download PDF
90. Constrained optimization of sensor placement for nuclear digital twins
- Author
-
Karnik, Niharika, Abdo, Mohammad G., Perez, Carlos E. Estrada, Yoo, Jun Soo, Cogliati, Joshua J., Skifton, Richard S., Calderoni, Pattrick, Brunton, Steven L., and Manohar, Krithika
- Subjects
Mathematics - Optimization and Control ,Computer Science - Machine Learning - Abstract
The deployment of extensive sensor arrays in nuclear reactors is infeasible due to challenging operating conditions and inherent spatial limitations. Strategically placing sensors within defined spatial constraints is essential for the reconstruction of reactor flow fields and the creation of nuclear digital twins. We develop a data-driven technique that incorporates constraints into an optimization framework for sensor placement, with the primary objective of minimizing reconstruction errors under noisy sensor measurements. The proposed greedy algorithm optimizes sensor locations over high-dimensional grids, adhering to user-specified constraints. We demonstrate the efficacy of optimized sensors by exhaustively computing all feasible configurations for a low-dimensional dynamical system. To validate our methodology, we apply the algorithm to the Out-of-Pile Testing and Instrumentation Transient Water Irradiation System (OPTI-TWIST) prototype capsule. This capsule is electrically heated to emulate the neutronics effect of the nuclear fuel. The TWIST prototype that will eventually be inserted in the Transient Reactor Test facility (TREAT) at the Idaho National Laboratory (INL), serves as a practical demonstration. The resulting sensor-based temperature reconstruction within OPTI-TWIST demonstrates minimized error, provides probabilistic bounds for noise-induced uncertainty, and establishes a foundation for communication between the digital twin and the experimental facility.
- Published
- 2023
91. Pyrolysis of Municipal Green Waste: A Modelling, Simulation and Experimental Analysis
- Author
-
Mohammed J. Kabir, Ashfaque Ahmed Chowdhury, and Mohammad G. Rasul
- Subjects
municipal green waste ,pyrolysis ,Aspen Plus simulation ,energy balance ,Technology - Abstract
Pyrolysis is the thermo-chemical conversion of carbonaceous feedstock in the absence of oxygen to produce bio-fuel (bio-oil, bio-char and syn-gas). Bio-fuel production from municipal green waste (MGW) through the pyrolysis process has attracted considerable attention recently in the renewable energy sector because it can reduce greenhouse gas emissions and contribute to energy security. This study analyses properties of MGW feedstock available in Rockhampton city of Central Queensland, Australia, and presents an experimental investigation of producing bio-fuel from that MGW through the pyrolysis process using a short sealed rotary furnace. It was found from the experiment that about 19.97% bio-oil, 40.83% bio-char and 29.77% syn-gas can be produced from the MGW. Then, a four-stage steady state simulation model is developed for pyrolysis process performance simulation using Aspen Plus software. In the first stage, the moisture content of the MGW feed is reduced. In the second stage, the MGW is decomposed according to its elemental constituents. In the third stage, condensate material is separated and, finally, the pyrolysis reactions are modelled using the Gibbs free energy minimisation approach. The MGW’s ultimate and proximate analysis data were used in the Aspen Plus simulation as input parameters. The model is validated with experimentally measured data. A good agreement between simulation and experimental results was found. More specifically, the variation of modelling and experimental elemental compositions of the MGW was found to be 7.3% for carbon, 15.82% for hydrogen, 7.04% for nitrogen and 5.56% for sulphur. The validated model is used to optimise the biofuel production from the MGW as a function of operating variables such as temperature, moisture content, particle size and process heat air–fuel ratio. The modelling and optimisation results are presented, analysed and discussed.
- Published
- 2015
- Full Text
- View/download PDF
92. Cysteine-Functionalized Chitosan Magnetic Nano-Based Particles for the Recovery of Light and Heavy Rare Earth Metals: Uptake Kinetics and Sorption Isotherms
- Author
-
Ahmed A. Galhoum, Mohammad G. Mafhouz, Sayed T. Abdel-Rehem, Nabawia A. Gomaa, Asem A. Atia, Thierry Vincent, and Eric Guibal
- Subjects
cysteine-grafting ,rare earth metals ,magnetic chitosan nanocomposites ,sorption isotherms ,uptake kinetics ,thermodynamics ,Chemistry ,QD1-999 - Abstract
Cysteine-functionalized chitosan magnetic nano-based particles were synthesized for the sorption of light and heavy rare earth (RE) metal ions (La(III), Nd(III) and Yb(III)). The structural, surface, and magnetic properties of nano-sized sorbent were investigated by elemental analysis, FTIR, XRD, TEM and VSM (vibrating sample magnetometry). Experimental data show that the pseudo second-order rate equation fits the kinetic profiles well, while sorption isotherms are described by the Langmuir model. Thermodynamic constants (ΔG°, ΔH°) demonstrate the spontaneous and endothermic nature of sorption. Yb(III) (heavy RE) was selectively sorbed while light RE metal ions La(III) and Nd(III) were concentrated/enriched in the solution. Cationic species RE(III) in aqueous solution can be adsorbed by the combination of chelating and anion-exchange mechanisms. The sorbent can be efficiently regenerated using acidified thiourea.
- Published
- 2015
- Full Text
- View/download PDF
93. Production, biodistribution, and dosimetry of 47Sc-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene phosphonic acid as a bone-seeking radiopharmaceutical
- Author
-
Fatemeh Fathi, Leila Moghaddam-Banaem, Mojtaba Shamsaei, Ali Samani, and Mohammad G Maragheh
- Subjects
47/46Sc-1 ,10-tetraazacyclododecane-1 ,10-tetramethylene phosphonic acid ,biodistribution ,dosimetry ,radiopharmaceuticals ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
In this study 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene phosphonic acid (DOTMP) was used as the polyaminophosphonic acid carrier ligand and the therapeutic potential of the bone seeking radiopharmaceutical 47Sc-DOTMP was assessed by measuring its dosage–dependent skeletal uptake and then the absorbed radiation dose of human organs was estimated. Because of limited availability of 47Sc we performed some preliminary studies using 46Sc. 46Sc was produced with a specific activity of 116.58 MBq/mg (3.15 mCi/mg) and radionuclide purity of 98%. 46Sc-DOTMP was prepared and an activity of 1.258 MBq (34 μCi) at a chelant-to-metal ratio of 60:1 was administered to five groups of mice with each group containing 3 mice that were euthanized at 4, 24, 48, 96 and 192 h post administration. The heart, lungs, liver, spleen, kidneys, intestine, skin, muscle, and a femur were excised, weighed, and counted. The data were analyzed to determine skeletal uptake and source organ residence times and cumulated activities for 47Sc-DOTMP. 46Sc-DOTMP complex was prepared in radiochemical purity about 93%. In vitro stability of complex was evaluated at room temperature for 48 h. Biodistribution studies of complex in mice were studied for 7 days. The data were analyzed to estimate skeletal uptake and absorbed radiation dose of human organs using biodistribution data from mice. By considering the results, 47Sc-DOTMP is a possible therapeutic agent for using in palliation of bone pain due to metastatic skeletal lesions from several types of primary cancers in prostate, breast, etc.
- Published
- 2015
- Full Text
- View/download PDF
94. Orchiopexy through a single high transverse scrotal incision
- Author
-
Mohammad G Khirallah, Mahmoud A Elafifi, Akram M Elbatarny, and Ahmed M Elsharaby
- Subjects
Orchiopexy ,scrotal incision ,undescended testis ,Pediatrics ,RJ1-570 ,Surgery ,RD1-811 - Abstract
Background: Palpable Undescended Testis (PUT) represents a common paediatric problem in many premature and some mature infants. There are several surgical techniques to correct PUT either through combined inguinal and scrotal incision or single transverse scrotal incision. This study assessed single high transverse scrotal incision for the management of PUT as regards to feasibility, postoperative success and final cosmetic results. Materials and Methods: One hundred twenty patients were managed at the Paediatric Surgery Department of Tanta University Hospital with PUT during the period from March 2010 to March 2014. They were all operated at the age of 6-12 months. We excluded recurrent cases, and cases older than 12 months. Through high transverse scrotal incision, the layers were divided, and the canal entered through the external ring, dissecting the PUT and bringing it through the incision. Hernia sac, if present, was ligated at the neck. Creation of the dartos pouch was then made through the same incision. All infants were followed-up at 1 month, 2 months and 6 months to detect any re-ascended cases, testicular atrophy and the final cosmetic appearance. Results: A total of 140 PUTs were operated upon in 120 patients. PUT was bilateral in 20 patients, right-sided in 65 cases and left-sided in 35 cases. Thirty testes were located at the external ring; the others were located within the inguinal canal. No cases needed a redo operation, and there was no case of postoperative testicular atrophy. Conclusion: Single high transverse incision was sufficient to deal with PUT especially, in young infants (age 6 months) with no need for conversion in most cases to the traditional two incisions technique, and good long term follow-up and a better cosmetic results.
- Published
- 2015
- Full Text
- View/download PDF
95. Outcome of upper limb vascular access for hemodialysis
- Author
-
Moaath Alsmady, Awni D Shahait, Izzat A Alawwa, Mohammad G Riziq, Abdel Munem Ali Abusba, and Abdullah Al-qudah
- Subjects
Medicine - Abstract
The aim of this study was to investigate the outcome of vascular access procedures for hemodialysis and factors affecting access survival and complication rates. A retrospective review was carried out on 276 patients who underwent 404 consecutive vascular access operations performed over seven-years. The overall primary failure rate was 9.2%, while the oneand five-year cumulative access patency rates were 63.8% and 40.6%, respectively. Diabetes mellitus status significantly influenced access survival (P = 0.022). Autogenous arteriovenous fistulas (AVFs) are reliable procedures with access sites often available in the upper limb proximally and distally. Patients with diabetes mellitus have significantly worse patency rates of upper limb AVFs.
- Published
- 2015
- Full Text
- View/download PDF
96. Magnetic BiFeO3 nanoparticles: a robust and efficient nanocatalyst for the green one-pot three-component synthesis of highly substituted 3,4-dihydropyrimidine-2(1H)-one/thione derivatives
- Author
-
Hanifi, Safa, Dekamin, Mohammad G., and Eslami, Mohammad
- Published
- 2024
- Full Text
- View/download PDF
97. Mapping reservoir water quality from Sentinel-2 satellite data based on a new approach of weighted averaging: Application of Bayesian maximum entropy
- Author
-
Nikoo, Mohammad Reza, Zamani, Mohammad G., Zadeh, Mahshid Mohammad, Al-Rawas, Ghazi, Al-Wardy, Malik, and Gandomi, Amir H.
- Published
- 2024
- Full Text
- View/download PDF
98. Performance Analysis of an Integrated Fixed Bed Gasifier Model for Different Biomass Feedstocks
- Author
-
Sharmina Begum, Mohammad G. Rasul, Delwar Akbar, and Naveed Ramzan
- Subjects
gasification ,fixed bed ,Aspen Plus ,syngas ,Technology - Abstract
Energy recovery from biomass by gasification technology has attracted significant interest because it satisfies a key requirement of environmental sustainability by producing near zero emissions. Though it is not a new technology, studies on its integrated process simulation and analysis are limited, in particular for municipal solid waste (MSW) gasification. This paper develops an integrated fixed bed gasifier model of biomass gasification using the Advanced System for Process ENngineering (Aspen) Plus software for its performance analysis. A computational model was developed on the basis of Gibbs free energy minimization. The model is validated with experimental data of MSW and food waste gasification available in the literature. A reasonable agreement between measured and predicted syngas composition was found. Using the validated model, the effects of operating conditions, namely air-fuel ratio and gasifier temperature, on syngas production are studied. Performance analyses have been done for four different feedstocks, namely wood, coffee bean husks, green wastes and MSWs. The ultimate and proximate analysis data for each feedstock was used for model development. It was found that operating parameters have a significant influence on syngas composition. An air-fuel ratio of 0.3 and gasifier temperature of 700 °C provides optimum performance for a fixed bed gasifier for MSWs, wood wastes, green wastes and coffee bean husks. The developed model can be useful for gasification of other biomasses (e.g., food wastes, rice husks, poultry wastes and sugarcane bagasse) to predict the syngas composition. Therefore, the study provides an integrated gasification model which can be used for different biomass feedstocks.
- Published
- 2013
- Full Text
- View/download PDF
99. An Experimental and Numerical Investigation of Fluidized Bed Gasification of Solid Waste
- Author
-
Sharmina Begum, Mohammad G. Rasul, Delwar Akbar, and David Cork
- Subjects
gasification ,fluidised bed ,Aspen Plus ,syngas ,Technology - Abstract
Gasification is a thermo-chemical process to convert carbon-based products such as biomass and coal into a gas mixture known as synthetic gas or syngas. Various types of gasification methods exist, and fluidized bed gasification is one of them which is considered more efficient than others as fuel is fluidized in oxygen, steam or air. This paper presents an experimental and numerical investigation of fluidized bed gasification of solid waste (SW) (wood). The experimental measurement of syngas composition was done using a pilot scale gasifier. A numerical model was developed using Advanced System for Process ENgineering (Aspen) Plus software. Several Aspen Plus reactor blocks were used along with user defined FORTRAN and Excel code. The model was validated with experimental results. The study found very similar performance between simulation and experimental results, with a maximum variation of 3%. The validated model was used to study the effect of air-fuel and steam-fuel ratio on syngas composition. The model will be useful to predict the various operating parameters of a pilot scale SW gasification plant, such as temperature, pressure, air-fuel ratio and steam-fuel ratio. Therefore, the model can assist researchers, professionals and industries to identify optimized conditions for SW gasification.
- Published
- 2013
- Full Text
- View/download PDF
100. Recent Developments in Solar Thermal Desalination Technologies: A Review
- Author
-
Ihsan Ullah and Mohammad G. Rasul
- Subjects
solar desalination ,fresh water ,desalination technologies ,environmental impacts ,cost of solar desalination ,Technology - Abstract
Fresh water resources are depleting rapidly as the water demand around the world continues to increase. Fresh water resources are also not equally distributed geographically worldwide. The best way to tackle this situation is to use solar energy for desalination to not only cater for the water needs of humanity, but also to offset some detrimental environmental effects of desalination. A comprehensive review of the latest literature on various desalination technologies utilizing solar energy is presented here. This paper also highlights the environmental impacts of desalination technologies along with an economic analysis and cost comparison of conventional desalination methods with different solar energy based technologies. This review is part of an investigation into integration of solar thermal desalination into existing grid infrastructure in the Australian context.
- Published
- 2018
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.