1
|
Kayanja O, Hassan MA, Hassanin A, Ohashi H, Khalil ASG. Optimization of isotropic MoS 2/PES membranes for efficient treatment of industrial oily wastewater. RSC Adv 2024; 14:12058-12070. [PMID: 38628476 PMCID: PMC11019293 DOI: 10.1039/d4ra01052c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2024] [Accepted: 04/01/2024] [Indexed: 04/19/2024] Open
Abstract
Elimination of tiny oil droplets nearly miscible with wastewater can be realized using membrane technology through ultrafiltration. The novelty of this work was to blend different phases of molybdenum disulfide (MoS2) in isotropic polyethersulfone (PES). We prepared isotropic PES membranes by optimizing nonsolvent vapour-induced phase separation (VIPS). Membranes were blended with MoS2 nanosheets of different phases to promote separation performance and antifouling resistance. FE-SEM revealed the flower-like surface morphology of MoS2 nanosheets. HR-TEM of MoS2 revealed 2H domains in the monolayer, flakes of a few layers and a d-spacing of 0.22 nm. Raman spectroscopy could be used to distinguish mixed-phase MoS2 from single-phase MoS2. Isotropic PES membranes modified with 70% 1T/2H MoS2 had a significantly high permeance to pure water (6911 kg m-2 h bar). The same membrane possessed a high efficiency of oil rejection of 98.78%, 97.85%, 99.83% for emulsions of industrial crude oil at 100, 1000 and 10 000 mg L-1, respectively. Removal of oil droplets from wastewater was dominated by a mechanism based on size exclusion. Isotropic PES modified with 2H MoS2 possessed superior oleophilicity, which resulted in low rejection of crude oil. Modified membranes showed excellent fouling resistance for three successive filtration cycles, as evidenced by enhanced antifouling parameters. Our study reveals how the phase composition of MoS2 nanosheets can significantly affect the performance of isotropic PES membranes during the ultrafiltration of oily wastewater.
Collapse
Affiliation(s)
- Oscar Kayanja
- Materials Science and Engineering Department, Egypt-Japan University of Science and Technology (E-JUST) 179 New Borg El-Arab City Alexandria Egypt
| | - Mohsen A Hassan
- Materials Science and Engineering Department, Egypt-Japan University of Science and Technology (E-JUST) 179 New Borg El-Arab City Alexandria Egypt
| | - Ahmed Hassanin
- Materials Science and Engineering Department, Egypt-Japan University of Science and Technology (E-JUST) 179 New Borg El-Arab City Alexandria Egypt
- Department of Textile Engineering, Faculty of Engineering, Alexandria University Alexandria 21544 Egypt
| | - Hidenori Ohashi
- Faculty of Engineering, Tokyo University of Agriculture and Technology (TUAT) 2-24-16, Naka-cho, Koganei Tokyo 184-8588 Japan
| | - Ahmed S G Khalil
- Institute of Basic and Applied Sciences, Egypt-Japan University of Science and Technology (E-JUST) 179 New Borg El-Arab City Alexandria Egypt
- Environmental and Smart Technology Group, Faculty of Science, Fayoum University 63514 Fayoum Egypt
| |
Collapse
|
2
|
Liang Y, Xu X, Zhao L, Lei C, Dai K, Zhuo R, Fan B, Cheng E, Hassan MA, Gao L, Mu X, Hu N, Zhang C. Advances of Strategies to Increase the Surface Charge Density of Triboelectric Nanogenerators: A Review. Small 2024; 20:e2308469. [PMID: 38032176 DOI: 10.1002/smll.202308469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 10/31/2023] [Indexed: 12/01/2023]
Abstract
Triboelectric nanogenerators (TENGs) have manifested a remarkable potential for harvesting environmental energy and have the prospects to be utilized for various uses, for instance, self-powered sensing devices, flexible wearables, and marine corrosion protection. However, the potential for further development of TENGs is restricted on account of their low output power that in turn is determined by their surface charge density. The current review majorly focuses on the selection and optimization of triboelectric materials. Subsequently, various methods capable of enhancing the surface charge density of TENGs, including environmental regulation, charge excitation, charge pumping, electrostatic breakdown, charge trapping, and liquid-solid structure are comprehensively reviewed. Lastly, the review is concluded by highlighting the existing challenges in enhancing the surface charge density of TENGs and exploring potential opportunities for future research endeavors in this area.
Collapse
Affiliation(s)
- Yu Liang
- School of Mechanical Engineering, Hebei University of Technology, Tianjin, 300401, P. R. China
- CAS Center for Excellence in Nanoscience, Beijing Key Laboratory of Micro-nano Energy and Sensor, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, P. R. China
| | - Xinyu Xu
- School of Mechanical Engineering, Hebei University of Technology, Tianjin, 300401, P. R. China
- Key Laboratory of Optoelectronic Technology & Systems Ministry of Education, International R & D center of Micro-nano Systems and New Materials Technology, Chongqing University, Chongqing, 400044, P. R. China
| | - Libin Zhao
- School of Mechanical Engineering, Hebei University of Technology, Tianjin, 300401, P. R. China
- Key Laboratory of Advanced Intelligent Protective Equipment Technology, Ministry of Education, Tianjin, 300401, P. R. China
- Key Laboratory of Hebei Province on Scale-span Intelligent Equipment Technology, Hebei University of Technology, Tianjin, 300401, P. R. China
| | - Chenyang Lei
- School of Mechanical Engineering, Hebei University of Technology, Tianjin, 300401, P. R. China
| | - Kejie Dai
- School of Electrical and Mechanical Engineering, Pingdingshan University, Pingdingshan, 467000, P. R. China
| | - Ran Zhuo
- Electric Power Research Institute, China Southern Power Grid Company Ltd., Guangzhou, 510080, P. R. China
| | - Beibei Fan
- CAS Center for Excellence in Nanoscience, Beijing Key Laboratory of Micro-nano Energy and Sensor, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, P. R. China
| | - E Cheng
- School of Mechanical Engineering, Hebei University of Technology, Tianjin, 300401, P. R. China
| | - Mohsen A Hassan
- Industrial and Manufacturing Department, Faculty of Innovative Design Engineering, Egypt-Japan University for Science and Technology (E-JUST), New Borg Al-Arab City, 21934, Egypt
| | - Lingxiao Gao
- School of Mechanical Engineering, Hebei University of Technology, Tianjin, 300401, P. R. China
| | - Xiaojing Mu
- Key Laboratory of Optoelectronic Technology & Systems Ministry of Education, International R & D center of Micro-nano Systems and New Materials Technology, Chongqing University, Chongqing, 400044, P. R. China
| | - Ning Hu
- School of Mechanical Engineering, Hebei University of Technology, Tianjin, 300401, P. R. China
- State Key Laboratory of Reliability and Intelligence Electrical Equipment, Hebei University of Technology, Tianjin, 300401, P. R. China
| | - Chi Zhang
- CAS Center for Excellence in Nanoscience, Beijing Key Laboratory of Micro-nano Energy and Sensor, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, P. R. China
| |
Collapse
|
3
|
Youssef M, El-Shenawy EH, Khair-Eldeen W, Adachi T, Nofal A, Hassan MA. The Influences of Nb Microalloying and Grain Refinement Thermal Cycling on Microstructure and Tribological Properties of Armox 500T. Materials (Basel) 2023; 16:7485. [PMID: 38068229 PMCID: PMC10707768 DOI: 10.3390/ma16237485] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 11/18/2023] [Accepted: 11/23/2023] [Indexed: 03/11/2024]
Abstract
This study aims to investigate the combined effect of niobium (Nb) microalloying and austenite grain refinement, using a specific heat treatment cycle, on the microstructure and tribological properties of Armox 500T steel. In this work, Nb addition and thermal cycling were utilized for grain refinement and enhancement of the mechanical properties of Armox 500T alloy, to provide improved protection via lightweight armor steel components with a high strength-to-weight ratio. The kinetics of transformation of the developed Armox alloys were studied using JMATPro version 13.2. The samples were subjected to two austenitizing temperatures, 1000 °C and 1100 °C, followed by 4 min of holding time and three consecutive thermal and rapid-quenching processes from 900 °C to room temperature. Scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX) was employed to analyze the microstructure, which primarily consists of four types of martensite: short and long lath martensite, blocky martensite, and equiaxed martensite. Additionally, a small percentage (not exceeding 3%) of carbide precipitates was observed. The wear characteristics of the investigated alloys were evaluated using a pin-on-disc tribometer. The results demonstrate that alloying with Nb and grain refinement using a thermal cycle significantly reduce the wear rate.
Collapse
Affiliation(s)
- Mervat Youssef
- School of Innovative Design Engineering (IDE), Egypt-Japan University of Science and Technology (E-JUST), Alexandria 21934, Egypt;
- Metal Casting Department, Manufacturing Technology Institute, Central Metallurgical Research and Development Institute (CMRDI), Cairo 11912, Egypt;
| | - Eman H. El-Shenawy
- Plastic Deformation Department, Metal Technology Institute, Central Metallurgical Research and Development Institute (CMRDI), Cairo 11912, Egypt;
| | - Wael Khair-Eldeen
- School of Innovative Design Engineering (IDE), Egypt-Japan University of Science and Technology (E-JUST), Alexandria 21934, Egypt;
| | - Tadaharu Adachi
- Department of Mechanical Engineering, Toyohashi University of Technology (TUT), Aichi 441-8122, Japan;
| | - Adel Nofal
- Metal Casting Department, Manufacturing Technology Institute, Central Metallurgical Research and Development Institute (CMRDI), Cairo 11912, Egypt;
| | - Mohsen A. Hassan
- School of Innovative Design Engineering (IDE), Egypt-Japan University of Science and Technology (E-JUST), Alexandria 21934, Egypt;
| |
Collapse
|
4
|
Azab AR, Elnaggar RK, Abdelbasset WK, Alghadier M, Ahmed AS, Alsharidah AS, Morgan EN, Basha MA, Hassan MA, Kamel FH. Virtual reality-based exercises' effects on pulmonary functions, cardiopulmonary capacity, functional performance, and quality of life in children with repaired congenital diaphragmatic hernia. Eur Rev Med Pharmacol Sci 2023; 27:6480-6488. [PMID: 37522659 DOI: 10.26355/eurrev_202307_33118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
OBJECTIVE The long-term consequences of congenital diaphragmatic hernia (CDH), which include altered lung functions and compromised cardiopulmonary capacity, impact functional performance and quality of life. This study investigates the effects of virtual reality-based exercise programs on pulmonary functions, cardiopulmonary capacity, functional performance, and quality of life in children with repaired CDH. PATIENTS AND METHODS A randomized controlled clinical trial was performed. Fifty-two children with repaired CDH (aged 6-10 years) were enrolled and randomly allocated to virtual reality-based exercises plus traditional physical therapy (VR-EX group, n = 26) or traditional physical therapy alone (control group, n = 26). Interventions were conducted three times a week for 12 weeks. Pulmonary functions, cardiopulmonary capacity, functional performance, and quality of life were assessed before and after the intervention. RESULTS The VR-EX group demonstrated significantly enhanced post-treatment pulmonary functions and cardiopulmonary capacity compared to the control group after accounting for the pre-treatment values (p < 0.05). In addition, the values in functional performance and quality of life measures showed significantly larger improvements in the VR-EX group (p < 0.05). CONCLUSIONS Children with repaired CDH may benefit more from VR-based exercises when combined with traditional physical therapy than from traditional physical therapy alone regarding their pulmonary functions, cardiopulmonary capacity, functional performance, and quality of life.
Collapse
Affiliation(s)
- A R Azab
- Department of Health and Rehabilitation Sciences, College of Applied Medical Sciences, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Geriesh MM, Fath El-Bab AMR, Khair-Eldeen W, Mohamadien HA, Hassan MA. A Developed Jerk Sensor for Seismic Vibration Measurements: Modeling, Simulation and Experimental Verification. Sensors (Basel) 2023; 23:5730. [PMID: 37420895 DOI: 10.3390/s23125730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 06/07/2023] [Accepted: 06/12/2023] [Indexed: 07/09/2023]
Abstract
Acceleration-based sensors are widely used in indicating the severity of damage caused to structural buildings during dynamic events. The force rate of change is of interest when investigating the effect of seismic waves on structural elements, and hence the calculation of the jerk is necessary. For most sensors, the technique used for measuring the jerk (m/s3) is based on differentiating the time-acceleration signal. However, this technique is prone to errors especially in small amplitude and low frequency signals, and is deemed not suitable when online feedback is required. Here, we show that direct measurement of the jerk can be achieved using a metal cantilever and a gyroscope. In addition, we focus on the development of the jerk sensor for seismic vibrations. The adopted methodology optimized the dimensions of an austenitic stainless steel cantilever and enhanced the performance in terms of sensitivity and the jerk measurable range. We found, after several analytical and FE analyses, that an L-35 cantilever model with dimensions 35 × 20 × 0.5 (mm3) and a natural frequency of 139 (Hz) has a remarkable performance for seismic measurements. Our theoretical and experimental results show that the L-35 jerk sensor has a constant sensitivity value of 0.05 ((deg/s)/(G/s)) with ±2% error in the seismic frequency bandwidth of 0.1~40 (Hz) and for amplitudes in between 0.1 and 2 (G). Furthermore, the theoretical and experimental calibration curves show linear trends with a high correlation factor of 0.99 and 0.98, respectively. These findings demonstrate the enhanced sensitivity of the jerk sensor, which surpasses previously reported sensitivities in the literature.
Collapse
Affiliation(s)
- Mostafa M Geriesh
- Material Science and Engineering Program, School of Innovative Design Engineering, Egypt-Japan University of Science and Technology (E-JUST), New Borg Al-Arab City 21934, Egypt
- Civil Engineering Department, Faculty of Engineering, Suez Canal University, Ismailia 41522, Egypt
| | - Ahmed M R Fath El-Bab
- Mechatronics and Robotics Department, School of Innovative Design Engineering, Egypt-Japan University of Science and Technology (E-JUST), New Borg Al-Arab City 21934, Egypt
| | - Wael Khair-Eldeen
- Department of Industrial Engineering and Systems Management, School of Innovative Design Engineering, Egypt-Japan University of Science and Technology (E-JUST), New Borg Al-Arab City 21934, Egypt
| | - Hassan A Mohamadien
- Civil Engineering Department, Faculty of Engineering, Suez Canal University, Ismailia 41522, Egypt
| | - Mohsen A Hassan
- Material Science and Engineering Program, School of Innovative Design Engineering, Egypt-Japan University of Science and Technology (E-JUST), New Borg Al-Arab City 21934, Egypt
| |
Collapse
|
6
|
Nahid A, Haque ME, Asma AN, Hassan MA, Hassan MK, Chanda T, Siddika A. Dermatology Life Quality Index in Patients with Dermatophytosis in a Tertiary Care Centre of Bangladesh. Mymensingh Med J 2022; 31:522-530. [PMID: 35383775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In our country a huge number of populations are suffering from dermatophytosis. During the last few years, the number of patients affected by dermatophytosis has been increasing. Dermatophytosis tends to be prolonged, recurrent and persistent course which can affect quality of life (QoL). The aim of this study was to seek out the effect of dermatophytosis on the quality of life of the patients of dermatophytosis and to analyze its relationship with various demographic and clinical factors. This was a cross-sectional study in which 306 patients aged ≥16 years with dermatophytosis were included and evaluated for impact of dermatophytosis on quality of life using dermatology life quality index (DLQI) questionnaire. Independent sample t-test and one way ANOVA were used to find out statistical associations between various variables and mean DLQI scores, wherever applicable. The mean DLQI score in this study was 13.07±8.51. Majority (39.5%) subjects had a 'very large' effect on the QoL. Mean DLQI was significantly higher in young subjects, patients with longer duration of disease, more body surface area involved, involvement of more than one sites (generalized involvement) and topical steroid containing preparation users (p<0.05). This study revealed that the quality of life is adversely affected by dermatophytosis. Hence, Steps must be taken for proper counseling and management, along with early detection and elimination of topical steroid use in dermatophytosis.
Collapse
Affiliation(s)
- A Nahid
- Dr Afsana Nahid, Assistant Professor, Department of Dermatology and Venereology, Dhaka Medical College (DMC), Dhaka, Bangladesh; E-mail:
| | | | | | | | | | | | | |
Collapse
|
7
|
Ali MK, Hessein A, Hassan MA, Ghali M, Shaalan N, Nakamura K, El‐Moneim AA. Heteroatom‐doped reduced graphene oxide/polyaniline nanocomposites with improved n‐type thermoelectric performance. J Appl Polym Sci 2021. [DOI: 10.1002/app.50852] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Mariamu Kassim Ali
- Department of Materials Science and Engineering Egypt‐Japan University of Science and Technology New Borg El Arab City Alexandria Egypt
- Department of Mining Materials and Petroleum Engineering, Jomo Kenyatta University of Science and Technology Nairobi Kenya
| | - Amr Hessein
- Department of Mathematical and Physical Engineering, Faculty of Engineering (Shoubra) Benha University Cairo Egypt
- Graphene Center of Excellence for Energy and Electronic Applications Egypt‐Japan University of Science and Technology New Borg El Arab City Alexandria Egypt
| | - Mohsen A. Hassan
- Department of Materials Science and Engineering Egypt‐Japan University of Science and Technology New Borg El Arab City Alexandria Egypt
| | - Mohsen Ghali
- School of Basic and Applied Science Egypt‐Japan University of Science and Technology New Borg El Arab City Alexandria Egypt
| | - Nagih Shaalan
- Physics Department, Faculty of Science Assiut University Assiut 71516, Egypt Egypt
- Department of Physics College of Science, King Faisal University Al‐Ahsa, 31982 Saudi Arabia
| | - Koichi Nakamura
- Department of Mechanical and Electrical System Engineering Kyoto University of Advanced Science Kyoto Japan
- Center for the Promotion of Interdisciplinary Education and Research Kyoto University Kyoto Japan
| | - Ahmed Abd El‐Moneim
- Department of Materials Science and Engineering Egypt‐Japan University of Science and Technology New Borg El Arab City Alexandria Egypt
- Graphene Center of Excellence for Energy and Electronic Applications Egypt‐Japan University of Science and Technology New Borg El Arab City Alexandria Egypt
| |
Collapse
|
8
|
Abd El-baky MA, Attia MA, Abdelhaleem MM, Hassan MA. Mechanical characterization of hybrid composites based on flax, basalt and glass fibers. Journal of Composite Materials 2020; 54:4185-4205. [DOI: 10.1177/0021998320928509] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
An experimental study on tensile, flexural and impact properties of flax-basalt-glass reinforced epoxy hybrid composites is presented in this paper. Test specimens were fabricated by vacuum bagging process. The effects of reinforcement hybridization, fiber relative amounts and stacking sequence on the mechanical properties were investigated. Morphological studies of the fabricated and fractured surfaces through thickness were performed using scanning electron microscopy. Results showed that the developed hybrid composites display enhanced tensile, flexural and impact performance as compared with flax reinforced epoxy composite. The flexural strength increases when partial laminas from flax/epoxy laminate are replaced by basalt/epoxy and/or glass/epoxy laminas. Also, it is realized that incorporating high-strength fibers, i.e. glass or basalt, to the outer layers of the composite leads to higher flexural resistance, whilst the opposite was noticed for tensile properties. The fabricated hybrids were found to have economical and specific mechanical properties benefits. Fiber-relative amounts and stacking sequence have great effects on the mechanical properties. The mechanical properties of hybrid laminates are proven to be highly dependent on the position of the flax layers within the hybrid composite. The Hybridization with basalt and/or glass fibers is an effective method for enhancing the mechanical properties of flax/epoxy composites.
Collapse
Affiliation(s)
- MA Abd El-baky
- Mechanical Design and Production Engineering Department, Faculty of Engineering, Zagazig University, Egypt
| | - MA Attia
- Mechanical Design and Production Engineering Department, Faculty of Engineering, Zagazig University, Egypt
| | - MM Abdelhaleem
- Mechanical Design and Production Engineering Department, Faculty of Engineering, Zagazig University, Egypt
| | - MA Hassan
- Mechanical Design and Production Engineering Department, Faculty of Engineering, Zagazig University, Egypt
| |
Collapse
|
9
|
Abstract
Automatic Ingestion Monitor v2 (AIM-2) is an egocentric camera and sensor that aids monitoring of individual diet and eating behavior by capturing still images throughout the day and using sensor data to detect eating. The images may be used to recognize foods being eaten, eating environment, and other behaviors and daily activities. At the same time, captured images may carry privacy concerning content such as (1) people in social eating and/or bystanders (i.e., bystander privacy); (2) sensitive documents that may appear on a computer screen in the view of AIM-2 (i.e., context privacy). In this paper, we propose a novel approach based on automatic, image redaction for privacy protection by selective content removal by semantic segmentation using a deep learning neural network. The proposed method reported a bystander privacy removal with precision of 0.87 and recall of 0.94 and reported context privacy removal by precision and recall of 0.97 and 0.98. The results of the study showed that selective content removal using deep learning neural network is a much more desirable approach to address privacy concerns for an egocentric wearable camera for nutritional studies.
Collapse
Affiliation(s)
- M A Hassan
- Department of Electrical and Computer Engineering, The University of Alabama, Tuscaloosa, Al, 35401 USA
| | - E Sazonov
- Department of Electrical and Computer Engineering, The University of Alabama, Tuscaloosa, Al, 35401 USA
| |
Collapse
|
10
|
Abdelkhalik A, Makhlouf G, Hassan MA. A new implementation of EN1839 method T mixture preparation to prepare calibration gas mixtures for anesthetic gas monitors. J Clin Monit Comput 2020; 35:1069-1076. [PMID: 32643129 DOI: 10.1007/s10877-020-00554-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 06/29/2020] [Indexed: 10/23/2022]
Abstract
In this study different mixtures from anesthetic liquids vapours in air and O2-sevoflurane/air, sevoflurane/O2 and isoflurane/O2-were prepared according to EN1839 method T. The gases mixtures were used to calibrate anesthetic gas monitors. The targeted concentrations (TCs) from sevoflurane and isoflurane in air and O2 were 0 vol%, 0.15 vol%, 0.7 vol%, 1 vol%, 1.5 vol%, 2.5 vol%, 5 vol%, 6 vol% and 8 vol%. The values of liquids, air and O2 flow rates which are corresponding theoretically to the TCs were calculated. The results showed that the measured concentrations by anesthetic gas monitor are in good agreement with TCs. Full validation was performed to assure the suitability of the method for preparing gas mixtures to calibrate anesthetic gas monitors. Linearity, limit of detection (LOD), limit of quantification (LOQ), precision, method robustness and uncertainty of measurement results were evaluated in the validation study. The results indicated that the method is valid for the purpose of analysis.
Collapse
Affiliation(s)
- Aksam Abdelkhalik
- Fire and Explosion Protection Laboratory, National Institute of Standards, El-sadat street, El-Haram, P.O. Box 136, El-Giza, 12211, Egypt.
| | - Ghada Makhlouf
- Fire and Explosion Protection Laboratory, National Institute of Standards, El-sadat street, El-Haram, P.O. Box 136, El-Giza, 12211, Egypt
| | - M A Hassan
- Saudi Standards, Metrology and Quality Organization, P.O. Box 3437, Riyadh, 11471, Kingdom of Saudi Arabia
| |
Collapse
|
11
|
Rashed LA, Faiz SH, Hassan MA, Elsebaie MM, Saad AE. Circulating Micro RNA 181A as Biomarker in Breast Cancer, Its Possible Association with Metastasis & Epithelial Mesenchymal Transformation. Tumori 2020. [DOI: 10.1177/0300891620914122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Background: Recent studies have reported the involvement of micro RNA 181a in diverse cellular functions. Though some studies have shown that miR-181a expression is downregulated in several human solid tumors, others have demonstrated that upregulation of miR-181a may promote metastasis and invasion of human cancers. Aim of the Study: The aim of this work is to detect the level of circulating miRNA-181a in breast cancer cases at different stages and to study its role in metastasis & epithelial mesenchymal transformation (EMT) through the possible association between miRNA 181a and transforming growth factor beta (TGFβ) signaling pathway. Subjects and Methods: The present work included 70 female patients, with breast cancer at different stages 30 patients with metastatic disease and 40 patients with non-metastatic disease 20 healthy subjects were taken as a control group. We detected miRNA-181a expression in peripheral blood with qRT PCR, and TGF-beta, SMAD-4, SNAIL-1 and Bim expression by quantitative PCR. Results: miRNA-181a, TGF-beta, SNAIL-1 and SMAD-4 were significantly upregulated in patients with metastatic breast cancer compared to patients with non-metastatic disease while Bim is significantly downregulated in metastatic versus non-metastatic group. Also, miRNA-181a was a prognostic marker for disease progression and overall survival. Conclusion: signaling pathway of TGFβ-SMAD, regulate miRNA-181a which in turn play role in stabilizing SNAIL transcription factor that promote tumor aggressiveness and metastasis through epithelial mesenchymal transition, as well as down-regulation of Bim.
Collapse
Affiliation(s)
- LA Rashed
- Department of Medical Biochemistry and Molecular Biology, faculty of medicine, Cairo university
| | - SH Faiz
- Department of Medical Biochemistry and Molecular Biology, faculty of medicine, Cairo university
| | - MA Hassan
- Department of Clinical oncology, Faculty of medicine, Cairo University
| | - MM Elsebaie
- Department of Medical Biochemistry and Molecular Biology, faculty of medicine, Cairo university
| | - AE Saad
- Department of Medical Biochemistry and Molecular Biology, faculty of medicine, Cairo university
| |
Collapse
|
12
|
Hassan MA, Sazonov E. Orientation-Based Food Image Capture for Head Mounted Egocentric Camera. Annu Int Conf IEEE Eng Med Biol Soc 2020; 2019:7145-7148. [PMID: 31947482 DOI: 10.1109/embc.2019.8857078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Current head-mounted wearable sensors for monitoring of food intake operates by fusing multiple modalities such as inertial and image sensing. The image capture may be performed periodically, capturing a large number of irrelevant images, increasing power consumption and reducing the battery life. In this manuscript, we propose an efficient approach for food image capture, that captures the images only when the head tilt angle estimated from the accelerometer data matches that during ingestion of food. The method was developed and validated using data from 15 volunteers consuming unrestricted meals in a free-living environment between 12.5 to 18.5 hours. The tilt angle of the head was computed using 3D accelerometer data. A classifier for image capture was developed using a curve fitting approach on the tilt angles of the head. The proposed method achieved a sensitivity of 0.97 and specificity of 0.47 in predicting capture of food images, thus potentially improving the battery life of the wearable device.
Collapse
|
13
|
Shaker A, Hassanin AH, Shaalan NM, Hassan MA, El-Moneim AA. Micropatterned flexible strain gauge sensor based on wet electrospun polyurethane/PEDOT: PSS nanofibers. Smart Mater Struct 2019; 28:075029. [DOI: 10.1088/1361-665x/ab20a2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
|
14
|
Obeid KM, Hassan MA, Chinnakotla S, Young JH. Genitourinary Tract Infection Due to Mycobacterium avium intracellulare Complex Infection in Pretransplant Setting With Recurrence Following Transplant: A Case Report. Transplant Proc 2018; 50:3937-3939. [PMID: 30577290 DOI: 10.1016/j.transproceed.2018.09.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 09/05/2018] [Indexed: 11/26/2022]
Abstract
Genitourinary (GU) tract infection with Mycobacterium avium intracellulare complex (MAI) is very rare and, to our knowledge, has never been reported in the solid organ transplant literature. CASE DESCRIPTION: A 61-year-old Somali-born woman had a history of liver cirrhosis due to chronic hepatitis C infection. She was diagnosed as having and treated for latent tuberculosis infection and GU tract infection due to MAI. She received a total of 17 months antimycobacterial therapy consisting of azithromycin, ethambutol, and moxifloxacin. Within 5 months of the initiation of antimicrobial therapy, there was documented sterilization of urine mycobacterial cultures. Liver and kidney transplant was performed 3 months after finishing the treatment course. One year following transplant, GU tract infection due to MAI recurred. She declined further diagnostic testing as well as mycobacterial therapy. She died 15 months following transplant for reasons not related to infections. CONCLUSION: The treatment of MAI infection in solid organ transplant candidates and recipients is challenging, and the duration of therapy in this population is not known. The recurrence of infection following transplant in this case may argue in favor of a duration that extends beyond the date of transplant. The combination of a fluoroquinolone and ethambutol may successfully prevent reactivation of tuberculosis in patients with history of latent tuberculosis infection and deserves further evaluation.
Collapse
Affiliation(s)
- K M Obeid
- Program in Adult Transplant Infectious Disease, Division of Infectious Disease and International Medicine, Department of Medicine, University of Minnesota, Minneapolis, Minnesota.
| | - M A Hassan
- Division of Gastroenterology, Department of Medicine, University of Minnesota, Minneapolis, Minnesota
| | - S Chinnakotla
- Division of Transplantation, Department of Surgery, University of Minnesota, Minneapolis, Minnesota
| | - J H Young
- Program in Adult Transplant Infectious Disease, Division of Infectious Disease and International Medicine, Department of Medicine, University of Minnesota, Minneapolis, Minnesota
| |
Collapse
|
15
|
Hassan MA, Malik AS, Saad N, Fofi D, Meriaudeau F. Effect of motion artifact on digital camera based heart rate measurement. Annu Int Conf IEEE Eng Med Biol Soc 2018; 2017:2851-2854. [PMID: 29060492 DOI: 10.1109/embc.2017.8037451] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Remote health monitoring is an emerging field in biomedical technology. Digital camera based heart rate measurement method is a recent development which would make remote health monitoring reliable and sustainable in future. This paper presents an investigation on the effect of motion artifact on digital camera-based heart rate measurement. The paper will discuss details on the principles and effects of motion artifacts on photoplethysmography signals. An experiment is conducted using publicly available MAHNOB-HCI database. We have investigated the effects of static scenarios, scenarios involving rigid motion and scenarios involving non-rigid motion. The experiment was tested on state of the art digital camera based heart rate measuring methods. The results showed the effectiveness of the methods and provide a direction to overcome/minimize the effect of motion artifacts for future research.
Collapse
|
16
|
Yusof SJHM, Roslan AM, Ibrahim KN, Abdullah SSS, Zakaria MR, Hassan MA, Shirai Y. Environmental performance of bioethanol production from oil palm frond petiole sugars in an integrated palm biomass biorefinery. ACTA ACUST UNITED AC 2018. [DOI: 10.1088/1757-899x/368/1/012004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
17
|
Ujang FA, Osman NA, Idris J, Halmi MIE, Hassan MA, Roslan AM. Start-up treatment of palm oil mill effluent (POME) final discharge using Napier Grass in wetland system. ACTA ACUST UNITED AC 2018. [DOI: 10.1088/1757-899x/368/1/012008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
18
|
|
19
|
Aleem A, El-Sharief MA, Hassan MA, El-Sebaie MG. Implementation of Fuzzy and Adaptive Neuro-Fuzzy Inference Systems in Optimization of Production Inventory Problem. ACTA ACUST UNITED AC 2017. [DOI: 10.18576/amis/110135] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
20
|
Hassan MA, Aftabuddin M, Meena DK, Mishal P, Gupta SD. Effective utilization of distiller's grain soluble-an agro-industrial waste in the feed of cage-reared minor carp Labeo bata in a tropical reservoir, India. Environ Sci Pollut Res Int 2016; 23:16090-5. [PMID: 27146546 DOI: 10.1007/s11356-016-6732-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Accepted: 04/20/2016] [Indexed: 06/05/2023]
Abstract
A 60-day feeding trial was conducted to evaluate the efficacy of distiller's grain soluble (brewery waste) as a prospective ingredient to substitute expensive and high demand feed component, soybean meal for farming Labeo bata in cages installed in tropical reservoir. Two isonitrogenous and isocaloric diets comprising brewery waste (49.2 % CP) as test diet and soybean meal (44.4 % CP) as reference diet were formulated and extruded to obtain 2-mm floating pellets. The efficacy of the diets was tested in terms of survival (%), live weight gain (%), SGR (%/day), FCR, PER and ANPU and recorded 65 ± 0.2, 96 ± 8.1, 1.9 ± 0.1, 2.5 ± 0.02, 1.4 ± 0.1, 20.3 ± 2.0 and 66 ± 0.6, 112 ± 9.8, 2.2 ± 0.1, 2.2 ± 0.2, 1.6 ± 0.1 and 20 ± 2.1, respectively, for soybean and brewer's waste-based formulated feed. The analyses of results revealed that survival, growth parameters and biochemical composition of whole body tissue did not differ significantly (p > 0.05) despite complete replacement of soybean meal by brewery waste. However, the cost estimate of diet revealed marked reduction of feed cost of Rs. 9.2/kg (33.8 %) in the test diet as compared to the reference diet. The study suggests that brewery waste could effectively replace soybean meal without effecting survival and growth of the fish. The finding thus may pave a productive way for reducing environmental pressure of disposal of an agro-industrial waste.
Collapse
Affiliation(s)
- M A Hassan
- Feed Research Laboratory, ICAR- Central Inland Fisheries Research Institute, Kolkata, 700120, India
| | - Md Aftabuddin
- Feed Research Laboratory, ICAR- Central Inland Fisheries Research Institute, Kolkata, 700120, India
| | - D K Meena
- Feed Research Laboratory, ICAR- Central Inland Fisheries Research Institute, Kolkata, 700120, India.
| | - P Mishal
- Feed Research Laboratory, ICAR- Central Inland Fisheries Research Institute, Kolkata, 700120, India.
| | - S Das Gupta
- Feed Research Laboratory, ICAR- Central Inland Fisheries Research Institute, Kolkata, 700120, India
| |
Collapse
|
21
|
Kakar KU, Ren XL, Nawaz Z, Cui ZQ, Li B, Xie GL, Hassan MA, Ali E, Sun GC. A consortium of rhizobacterial strains and biochemical growth elicitors improve cold and drought stress tolerance in rice (Oryza sativa L.). Plant Biol (Stuttg) 2016; 18:471-83. [PMID: 26681628 DOI: 10.1111/plb.12427] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 12/11/2015] [Indexed: 05/20/2023]
Abstract
In the present study, a consortium of two rhizobacteria Bacillus amyloliquefaciens Bk7 and Brevibacillus laterosporus B4, termed 'BB', biochemical elicitors salicylic acid and β-aminobutyric acid (SB) and their mixture (BBSB) were investigated for cold and drought stress tolerance in rice plants. After withholding water for 16 days, rice plants treated with BBSB showed 100% survival, improved seedling height (35.4 cm), shoot number (6.12), and showed minimum symptoms of chlorosis (19%), wilting (4%), necrosis (6%) and rolling of leaves. Similarly, BB inoculation enhanced plant growth and reduced overall symptoms in rice seedlings subjected to 0 ± 5 °C for 24 h. Our results imply several mechanisms underlying BB- and BBSB-elicited stress tolerance. In contrast to the control, both treatments significantly decreased leaf monodehydroascorbate (MDA) content and electrolyte leakage, and increased leaf proline and cholorophyll content. Moreover, activities of antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT) increased 3.0- and 3.6-fold, respectively. Moreover, expression of OsMYB3R-2, OsDIL, OsDREB1A and OsCDPK13 genes was significantly up-regulated, suggesting that these genes play important roles in abiotic stress tolerance of rice. In addition, bacterial strains Bk7 and B4 were able to produce high amounts of IAA and siderophores, and colonise the plant roots, while only strain Bk7 exhibited the capability to form biofilms and solubilise inorganic phosphate. This study indicates that the BB and BBSB bio-formulations can be used to confer induced systematic tolerance and improve the health of rice plants subject to chilling and drought stress.
Collapse
Affiliation(s)
- K U Kakar
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
- Guizhou Academy of Tobacco Science, Guiyang, China
| | - X-L Ren
- Guizhou Academy of Tobacco Science, Guiyang, China
| | - Z Nawaz
- Guizhou Academy of Tobacco Science, Guiyang, China
| | - Z-Q Cui
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - B Li
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - G-L Xie
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - M A Hassan
- University of Maiduguri, Maiduguri, Nigeria
| | - E Ali
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - G-C Sun
- State Key Laboratory Breeding Base for Zhejiang Sustainable Plant Pest and Disease Control, Key Laboratory of Detection for Pesticide Residues, Ministry of Agriculture, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| |
Collapse
|
22
|
Hassan AN, Hassan MA, Abdrahman AA, Elshallaly GH, Saleh MA. Assessment of existing practices in the operating theatre in the Khartoum North Teaching Hospital, Sudan. ACTA ACUST UNITED AC 2015. [DOI: 10.1080/10158782.2011.11441429] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- A N Hassan
- Department of Microbiology and Pathology, Medical Faculty, Alzaiem Alazhari University, Sudan
| | - M A Hassan
- Department of Community Medicine, Medical Faculty, Alzaiem Alazhari University, Sudan
| | - A A Abdrahman
- Department of Surgery, Medical Faculty, Alzaiem Alazhari University, Sudan
| | - G H Elshallaly
- Department of Surgery, Medical Faculty, Alzaiem Alazhari University, Sudan
| | - M A Saleh
- Medical student, Medical Faculty, Alzaiem Alazhari University, Sudan
| |
Collapse
|
23
|
El-Asmar KM, Hassan MA, Abdelkader HM, Hamza AF. Topical mitomycin C can effectively alleviate dysphagia in children with long-segment caustic esophageal strictures. Dis Esophagus 2015; 28:422-7. [PMID: 24708423 DOI: 10.1111/dote.12218] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Caustic ingestion in children and the resulting long esophageal strictures are usually difficult to be managed, and eventually, esophageal replacement was required for cases refractory to frequent dilatation sessions. Topical mitomycin C (MMC) application has been used recently to improve the results of endoscopic dilatation for short esophageal strictures. The study aims to assess the role of MMC application in management of long-segment caustic esophageal strictures. From January 2009 to June December 2013, patients presented with long caustic esophageal stricture (>3 cm in length) were included in this study and subjected to topical MMC application after endoscopic esophageal dilatation on multiple sessions. Regular follow-up and re-evaluation were done. A dysphagia score was used for close follow-up clinically; verification was done radiologically and endoscopically. During the specified follow-up period, 21 patients with long caustic esophageal stricture were subjected to topical MMC application sessions. Clinical, radiological, and endoscopic resolution of strictures occurred in 18 patients (85.7% cure rate). Number of dilatation sessions to achieve resolution of dysphagia was (n = 14.3 ± 5.7) with application of mitomycin two to six times. There was no recurrence in short- and mid-term follow-up. No complications were encountered related to topical MMC application. MMC is a promising agent in management of long-segment caustic esophageal strictures. Long-term follow-up is needed to prove its efficacy and to evaluate potential long-term side-effects of MMC application.
Collapse
Affiliation(s)
- K M El-Asmar
- Department of Pediatric Surgery, Ain Shams University, Cairo, Egypt
| | - M A Hassan
- Department of Otolaryngology, Ain Shams University, Cairo, Egypt
| | - H M Abdelkader
- Department of Pediatric Surgery, Ain Shams University, Cairo, Egypt
| | - A F Hamza
- Department of Pediatric Surgery, Ain Shams University, Cairo, Egypt
| |
Collapse
|
24
|
Obaid HA, Hassan MA, Mahdy NH, ElDisouky MI, Alzarba FE, Alnayeemi SR, Rillera MC, AlMazrooei BS. Tobacco use and associated factors among school students in Dubai, 2010: intervention study. East Mediterr Health J 2015; 20:765-773. [PMID: 25664514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 06/25/2014] [Indexed: 06/04/2023]
Abstract
Tobacco smoking is an emerging problem among adolescents in the United Arab Emirates (UAE). This study aimed to measure the prevalence of current tobacco use and its associated factors among school students in Dubai Emirate and to determine the impact of an intervention programme on knowledge and attitudes towards tobacco use. A school-based intervention programme was carried out among 2457 students aged 10-20 years and data were collected with a self-administered questionnaire. Of the students, 14.6% were tobacco users, mostly cigarettes (11.2%) and waterpipes (2.2%). The most common self-reported reasons for smoking were for the experience (29.4%), for stress relief (22.5%) and because their peers smoked (21.9%). Stepwise logistic regression analysis showed that the predictors of tobacco use were: male, higher age, UAE national, higher school level, government school, low knowledge about tobacco and family history of smoking. There were significant improvements in knowledge and attitudes scores after the health education intervention programme.
Collapse
Affiliation(s)
- H A Obaid
- Primary Health Care, Dubai Health Authority, Dubai, United Arab Emirates
| | - M A Hassan
- Primary Health Care, Dubai Health Authority, Dubai, United Arab Emirates
| | - N H Mahdy
- Primary Health Care, Dubai Health Authority, Dubai, United Arab Emirates
| | - M I ElDisouky
- Primary Health Care, Dubai Health Authority, Dubai, United Arab Emirates
| | - F E Alzarba
- Primary Health Care, Dubai Health Authority, Dubai, United Arab Emirates
| | - S R Alnayeemi
- Primary Health Care, Dubai Health Authority, Dubai, United Arab Emirates
| | - M C Rillera
- Primary Health Care, Dubai Health Authority, Dubai, United Arab Emirates
| | - B S AlMazrooei
- Primary Health Care, Dubai Health Authority, Dubai, United Arab Emirates
| |
Collapse
|
25
|
Hassaballah AI, Hassan MA, Mardi AN, Hamdi M. An inverse finite element method for determining the tissue compressibility of human left ventricular wall during the cardiac cycle. PLoS One 2013; 8:e82703. [PMID: 24367544 PMCID: PMC3868589 DOI: 10.1371/journal.pone.0082703] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 10/26/2013] [Indexed: 11/18/2022] Open
Abstract
The determination of the myocardium's tissue properties is important in constructing functional finite element (FE) models of the human heart. To obtain accurate properties especially for functional modeling of a heart, tissue properties have to be determined in vivo. At present, there are only few in vivo methods that can be applied to characterize the internal myocardium tissue mechanics. This work introduced and evaluated an FE inverse method to determine the myocardial tissue compressibility. Specifically, it combined an inverse FE method with the experimentally-measured left ventricular (LV) internal cavity pressure and volume versus time curves. Results indicated that the FE inverse method showed good correlation between LV repolarization and the variations in the myocardium tissue bulk modulus K (K = 1/compressibility), as well as provided an ability to describe in vivo human myocardium material behavior. The myocardium bulk modulus can be effectively used as a diagnostic tool of the heart ejection fraction. The model developed is proved to be robust and efficient. It offers a new perspective and means to the study of living-myocardium tissue properties, as it shows the variation of the bulk modulus throughout the cardiac cycle.
Collapse
Affiliation(s)
- Abdallah I. Hassaballah
- Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- Center of Advanced Manufacturing & Material processing, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- * E-mail:
| | - Mohsen A. Hassan
- Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- Center of Advanced Manufacturing & Material processing, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- Department of Mechanical Engineering, Faculty of Engineering, Assiut University, Assiut, Egypt
| | - Azizi N. Mardi
- Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- Center of Advanced Manufacturing & Material processing, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
| | - Mohd Hamdi
- Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
- Center of Advanced Manufacturing & Material processing, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
26
|
Ibrahim MF, Razak MNA, Phang LY, Hassan MA, Abd-Aziz S. Crude cellulase from oil palm empty fruit bunch by Trichoderma asperellum UPM1 and Aspergillus fumigatus UPM2 for fermentable sugars production. Appl Biochem Biotechnol 2013; 170:1320-35. [PMID: 23666614 DOI: 10.1007/s12010-013-0275-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2013] [Accepted: 04/29/2013] [Indexed: 11/25/2022]
Abstract
Cellulase is an enzyme that converts the polymer structure of polysaccharides into fermentable sugars. The high market demand for this enzyme together with the variety of applications in the industry has brought the research on cellulase into focus. In this study, crude cellulase was produced from oil palm empty fruit bunch (OPEFB) pretreated with 2% NaOH with autoclave, which was composed of 59.7% cellulose, 21.6% hemicellulose, and 12.3% lignin using Trichoderma asperellum UPM1 and Aspergillus fumigatus UPM2. Approximately 0.8 U/ml of FPase, 24.7 U/ml of CMCase and 5.0 U/ml of β-glucosidase were produced by T. asperellum UPM1 at a temperature of 35 °C and at an initial pH of 7.0. A 1.7 U/ml of FPase, 24.2 U/ml of CMCase, and 1.1 U/ml of β-glucosidase were produced by A. fumigatus UPM2 at a temperature of 45 °C and at initial pH of 6.0. The crude cellulase was best produced at 1% of substrate concentration for both T. asperellum UPM1 and A. fumigatus UPM2. The hydrolysis percentage of pretreated OPEFB using 5% of crude cellulase concentration from T. asperellum UPM1 and A. fumigatus UPM2 were 3.33% and 19.11%, with the reducing sugars concentration of 1.47 and 8.63 g/l, respectively.
Collapse
Affiliation(s)
- M F Ibrahim
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
| | | | | | | | | |
Collapse
|
27
|
Abstract
BACKGROUND/OBJECTIVES Menarche, the first menstrual period, is influenced by many factors including socio-economic status and rural or urban dwelling. The aims of the study were to compare the age at menarche between rural and urban girls and evaluate the anthropometric indices at menarche. MATERIALS AND METHODS A cross-sectional study of rural secondary school girls and urban school girls. A structured questionnaire was used to obtain information on their age at menarche and other relevant data. Their weights and heights were measured using computerized scales and calibrated walls. RESULTS Two hundred and twenty eight (228) rural girls and four hundred and eighty (480) urban girls that had attained menarche within a year were studied. Mean age at menarche for all the girls was 15.26 years. Mean menarcheal age for the rural and urban girls were 15.32 years and 15.20 years, respectively. Mean weight and height were 47.6 kg and 156.76 cm, respectively for the rural girls and 48.12 kg and 156.8 cm, respectively for the urban girls. There was no significance difference in age of menarche among the groups (P > 0.05). CONCLUSION The mean age at menarche for the school girls is 15.26 years. There was no difference in menarcheal age between the rural and urban school girls. Further longitudinal studies to compare rural school girls and urban school girls in private schools are required.
Collapse
Affiliation(s)
- K A Tunau
- Department of Obstetrics, Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria.
| | | | | | | | | |
Collapse
|
28
|
Sokker HH, El-Sawy NM, Hassan MA, El-Anadouli BE. Adsorption of crude oil from aqueous solution by hydrogel of chitosan based polyacrylamide prepared by radiation induced graft polymerization. J Hazard Mater 2011; 190:359-365. [PMID: 21497016 DOI: 10.1016/j.jhazmat.2011.03.055] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Revised: 03/04/2011] [Accepted: 03/15/2011] [Indexed: 05/30/2023]
Abstract
The adsorption of crude oil (initial concentration 0.5-30 g/L) from aqueous solution using hydrogel of chitosan based polyacrylamide (PAM) prepared by radiation induced graft polymerization has been investigated. The prepared hydrogel was characterized by FTIR and SEM micrographs. The experiments were carried out as a function of different initial concentrations of oil residue, acrylamide concentration, contact time and pH to determine the optimum condition for the adsorption of residue oil from aqueous solution and sea water. The results obtained showed that the hydrogel prepared at concentration of 40% acrylamide (AAm) and at a radiation dose of 5 kGy has high removal efficiency of crude oil 2.3g/g at pH 3. Equilibrium studies have been carried out to determine the capacity of the hydrogel for adsorption of crude oil, Langmuir and Freundlich adsorption models were applied to describe the experimental isotherms and isotherms constants. Equilibrium data were found to fit very well with both Freundlich and Langmuir models. Also the adsorption of oil onto the hydrogel behaves as a pseudo-second-order kinetic models rather than the pseudo-first-order kinetic model.
Collapse
Affiliation(s)
- H H Sokker
- Jazan University, Faculty of Science, Saudi Arabia. hesham
| | | | | | | |
Collapse
|
29
|
Abstract
A 43-year-old, who underwent a subtotal hysterectomy for postpartum hemorrhage following a normal delivery, 10 years ago, presented with a history of persistent vaginal discharge and post-coital bleeding. A pap smear reported moderate dysplasia, and a subsequent colposcopic biopsy reported severe dysplasia with crypt extension. The patient underwent a laparoscopic trachelectomy, and histology of the stump reported cervical squamous carcinoma in situ, with no microinvasion.
Collapse
Affiliation(s)
- Rafique B Parkar
- Consultant Obstetrician and Gynecologist, Specialist in Hysteroscopy and Laparoscopy, P.O. Box 520, Sarit Center, Nairobi, Kenya
| | | | | | | |
Collapse
|
30
|
Abstract
BACKGROUND So much has been written on vesicovaginal fistula (VVF) but there is little on the patients' perspective of the condition. The objectives of this study were to determine the knowledge of patients who have developed VVF on the causes of the fistula and their attitude toward measures that would prevent future occurrence. METHODS The questionnaire-based survey was conducted on VVF patients on admission from June to August 2003 at Maryam Abacha Women and Children Welfare Hospital, Sokoto, Nigeria. The case notes of the patients were reviewed after the interview to match the responses from the patients with those documented in the folders. Focus group discussions were held with the maternity staff to ascertain the content and quality of existing counseling. RESULTS One hundred and thirty patients were studied out of which 121 (93%) had no formal education. Teenagers constituted 37%, while 57% were primiparae. Thirty-five (27%) patients were divorced or separated because of the VVF. There were seven cases of recurrence after a previous successful repair. Prolonged obstructed labor was the cause of the VVF in 110 (85%) patients and 77 (70%) correctly attributed their problem to the prolonged labor. The 33 patients who could not identify the prolonged obstructed labor as the cause either attributed their condition to God/destiny or to the operation that was done to relief the obstruction and therefore would not have hospital delivery in their subsequent pregnancies. From the focus group discussions, it was confirmed that pre and post-operative counseling were inadequate. CONCLUSION Even though majority (70%) of the patients knew the cause of their fistula from the health talks, some (32%) would still not change from risky obstetric behavior. Mandatory provision of accurate and appropriate information and education to all VVF patients and their relatives or spouses by trained counselors should be ensured. Such information and education should emphasize the etiology and management of obstetric fistula in order to prevent a recurrence.
Collapse
Affiliation(s)
- M A Hassan
- Department of Obstetrics and Gynaecology, Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria.
| | | |
Collapse
|
31
|
Yusof N, Hassan MA, Phang LY, Tabatabaei M, Othman MR, Mori M, Wakisaka M, Sakai K, Shirai Y. Nitrification of ammonium-rich sanitary landfill leachate. Waste Manag 2010; 30:100-109. [PMID: 19811901 DOI: 10.1016/j.wasman.2009.08.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Revised: 08/21/2009] [Accepted: 08/31/2009] [Indexed: 05/28/2023]
Abstract
The nitrification of ammonium-rich wastewater is considered challenging due to the substrate inhibition particularly in the form of free ammonia (FA) and free nitrous acid (FNA) in ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB). The feasibility of the nitrifying activated sludge system to completely nitrify synthetic stabilized landfill leachate with N-NH(4)(+) concentration of 1452mg/L was tested in this study. The process started with 0.4kg N-NH(4)(+)/m(3)/day of nitrogen loading rate (NLR) in a fed-batch mode to avoid any accumulation of the FA and FNA in the system followed by increasing the nitrogen loading rate (NLR) gradually. Complete nitrification was achieved with a very high ammonium removal percentage (approximately 100%). The maximum specific and volumetric nitrification rate obtained were 0.49g N-NH(4)(+)/g VSS/day and 3.0kg N-NH(4)(+)/m(3)/day, respectively which were higher than those reported previously for ammonium-rich removal using activated sludge system. The nitrifying sludge exhibited good settling characteristics of up to 36mL/g VSS and a long SRT of more than 53 days which contributed to the success of the nitrification process. The coexistence and syntrophic association of the AOB and NOB was observed by using Fluorescence in situ hybridization (FISH) technique which supported the results on complete nitrification obtained in the system. These findings would be of prominent importance for further treatment of actual sanitary landfill leachate.
Collapse
Affiliation(s)
- N Yusof
- Department of Biological Functions and Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, Fukuoka, Japan.
| | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Yusof N, Haraguchi A, Hassan MA, Othman MR, Wakisaka M, Shirai Y. Measuring organic carbon, nutrients and heavy metals in rivers receiving leachate from controlled and uncontrolled municipal solid waste (MSW) landfills. Waste Manag 2009; 29:2666-2680. [PMID: 19564103 DOI: 10.1016/j.wasman.2009.05.022] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2009] [Revised: 05/23/2009] [Accepted: 05/26/2009] [Indexed: 05/28/2023]
Abstract
Since landfilling is the common method of waste disposal in Malaysia, river water is greatly exposed to the risk of contamination from leachate unless proper leachate management is carried out. In this study, leachates from three different types of landfills, namely active uncontrolled, active controlled and closed controlled, were characterized, and their relationships with river water chemistry were examined monthly for a year. The influence of leachate on river water chemistry from each type of landfill depended on many factors, including the presence of a leachate control mechanism, leachate characteristics, precipitation, surface runoff and the applied treatment. The impact of leachate from an active uncontrolled landfill was the highest, as the organic content, NH(4)(+)-N, Cd and Mn levels appeared high in the river. At the same time, influences of leachate were also observed from both types of controlled landfills in the form of inorganic nitrogen (NH(4)(+)-N, NO(3)(-)-N and NO(2)(-)-N) and heavy metals (Fe, Cr, Ni and Mn). Improper treatment practice led to high levels of some contaminants in the stream near the closed controlled landfill. Meanwhile, the active controlled landfill, which was located near the coastline, was exposed to the risk of contamination resulting from the pyrite oxidation of the surrounding area.
Collapse
Affiliation(s)
- N Yusof
- Department of Biological Functions and Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, Fukuoka 808-0196, Japan.
| | | | | | | | | | | |
Collapse
|
33
|
Hassan MA, Lund VJ, Howard DJ, Sacker AA. Are the demographics for squamous cell cancer in the head and neck changing in the United Kingdom? J Laryngol Otol 2006; 121:154-7. [PMID: 17059624 DOI: 10.1017/s0022215106004087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/23/2006] [Indexed: 11/06/2022]
Abstract
Head and neck squamous cell carcinoma is well known to be more common in men than women. Smoking and alcohol are the key risk factors causing such malignancies and there are several publications which have suggested that the prevalence of these diseases is increasing more in women than in men in western countries due to increased smoking and alcohol use. We collected our data at the Institute of Laryngology and Otology from the last 45 years and analysed the disease ratios in male to female patients in different sites within the head and neck. Our results revealed a decreasing male to female ratio, though this was not statistically significant. However, it draws attention to the increasing number of women with head and neck cancer, which may reflect their increasing use of cigarettes and alcohol.
Collapse
Affiliation(s)
- M A Hassan
- Department of Otolaryngology, Ain Shams University, Cairo, Egypt
| | | | | | | |
Collapse
|
34
|
Ong LGA, Abd-Aziz S, Noraini S, Karim MIA, Hassan MA. Enzyme Production and Profile by Aspergillus niger During Solid Substrate Fermentation Using Palm Kernel Cake as Substrate. Appl Biochem Biotechnol 2004; 118:73-9. [PMID: 15304740 DOI: 10.1385/abab:118:1-3:073] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2003] [Revised: 09/12/2003] [Accepted: 09/18/2003] [Indexed: 11/11/2022]
Abstract
The oil palm sector is one of the major plantation industries in Malaysia. Palm kernel cake is a byproduct of extracted palm kernel oil. Mostly palm kernel cake is wasted or is mixed with other nutrients and used as animal feed, especially for ruminant animals. Recently, palm kernel cake has been identified as an important ingredient for the formulation of animal feed, and it is also exported especially to Europe, South Korea, and Japan. It can barely be consumed by nonruminant (monogastric) animals owing to the high percentages of hemicellulose and cellulose contents. Palm kernel cake must undergo suitable pretreatment in order to decrease the percentage of hemicellulose and cellulose. One of the methods employed in this study is fermentation with microorganisms, particularly fungi, to partially degrade the hemicellulose and cellulose content. This work focused on the production of enzymes by Aspergillus niger and profiling using palm kernel cake as carbon source.
Collapse
Affiliation(s)
- L G A Ong
- Department of Biotechnology, Faculty of Food Science and Biotechnology, University Putra Malaysia, 43400 UPM Serdang, Selangor
| | | | | | | | | |
Collapse
|
35
|
Shehata AB, Hassan MA, Nour MA. Effect of new poly 2-acryloyl-N,N'-bis (4-nitrophenyl) propandiamide and poly 2-acryloyl-N,N'-bis (4-methylphenyl) propandiamide and their synergistic action on the stability of nitrocellulose. J Hazard Mater 2003; 102:121-136. [PMID: 12972232 DOI: 10.1016/s0304-3894(03)00138-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The stability of nitrocellulose can be significantly improved by incorporating two novel polymeric compounds as new stabilizers, each has two p-substituted phenyl rings in its repeating unit. The two prepared polymers were used independently and in three different blend ratios in comparison with the conventional propellant stabilizer, diphenylamine. The efficiency of the prepared stabilizers and their synergistic effect were evaluated using thermo gravimetric analysis (TGA), Bergmann-Junk test and differential scanning calorimetry (DSC). It was found that both polymers and their 50%:50% blend ratio are more efficient nitrocellulose stabilizers than diphenylamine.
Collapse
Affiliation(s)
- A B Shehata
- National institute for Standards, Tersa St., El-Haram, P.O. Box 136, 12211, Giza, Egypt.
| | | | | |
Collapse
|
36
|
Fathy M, Hassan MA, Mohamed FA. Differential scanning calorimetry to investigate the compatibility of ciprofloxacin hydrochloride with excipients. Pharmazie 2002; 57:825-8. [PMID: 12561245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
The compatibility between ciprofloxacin hydrochloride (CFX) and some excipients was evaluated using differential scanning calorimetry (DSC). Physical mixture, coground mixture, compressed mixture and kneaded mixture were prepared to study the effect of sample manipulation. In addition, the samples of physical mixture were also accelerated at 55 degrees C for three weeks to obtain more reliable conclusions. Different types of excipients currently used in tablet or capsule formulations namely, calcium phosphate dibasic dihydrate (Emcompress), magnesium stearate lactose, sorbitol, mannitol, croscarmellose sodium (Ac-Di-Sol), sodium carboxymethyl starch (Primojel), microcrystalline cellulose (Avicel PH 101, Emcocil) were examined. The DSC scan of CFX displayed two endothermic peaks probably as a result of a fusion process followed by a decomposition process. CFX appeared to interact with sorbitol, mannitol, Ac-Di-Sol, Primojel, Avicel PH 101 and Emcocil.
Collapse
Affiliation(s)
- M Fathy
- Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut, Egypt.
| | | | | |
Collapse
|
37
|
Macklon NS, Pieters MHEC, Hassan MA, Jeucken PHM, Eijkemans MJC, Fauser BCJM. A prospective randomized comparison of sequential versus monoculture systems for in-vitro human blastocyst development. Hum Reprod 2002; 17:2700-5. [PMID: 12351551 DOI: 10.1093/humrep/17.10.2700] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Extending the period of in-vitro culture to the blastocyst stage may improve implantation rates in IVF treatment. Recognition of the dynamic nature of early embryo metabolism has led to the development of commercially available sequential culture systems. However, their improved efficacy over monoculture systems remains to be demonstrated in prospective studies. METHODS Embryos obtained from 158 women undergoing IVF treatment were randomized by sealed envelopes to culture in one of three systems: (A) culture for 5 days in our own monoculture medium (Rotterdam medium); (B) culture for 3 days in Rotterdam medium followed by 2 days in fresh Rotterdam medium; (C) culture for 5 days using the commercially available G1/G2 sequential culture system. RESULTS There were no significant differences in blastulation, implantation or pregnancy rates between the three tested culture systems. CONCLUSION The employed monoculture system is as effective as the G1/G2 sequential system for the culture of blastocysts for IVF.
Collapse
Affiliation(s)
- N S Macklon
- Division of Reproductive Medicine, Department of Obstetrics and Gynaecology, Rotterdam, The Netherlands.
| | | | | | | | | | | |
Collapse
|
38
|
Hassan MA, Khan Z, Yunus M, Bhargava R. Health profile of lock factory workers in Aligarh. Indian J Public Health 2002; 46:39-45. [PMID: 12653000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023] Open
Abstract
In order to assess the health problems and its relationship to the nature of work of lock factory workers, a field based cross sectional study was carried out in sixty randomly selected lock factories in urban industrial areas of Aligarh city. Nine hundred fifty seven lock factory workers were included in the study out of them 45.7 percent were found to be suffering from one or more than one diseases. Detailed study of the workers showed that 73.05 percent were suffering from respiratory tract diseases, a majority of them having upper respiratory tract infection. Diseases showed a definite trend either increasing (Chronic bronchitis, Emphysema etc) or decreasing (upper respiratory tract infection, Bronchial asthma, Injuries & accidents), according to the age and duration of work. Polishing & filing appeared to be the most hazardous type of the work as shown in the proportion of chest diseases, (56.6%) & (38.3%) in polishing & filling workers respectively.
Collapse
Affiliation(s)
- M A Hassan
- Deptt of Community Medicine, J.N. Medical College, Aligarh
| | | | | | | |
Collapse
|
39
|
Abstract
Three malonanilide dimers (MA2-MA4) were prepared by the reaction of ethyl malonate with malonanilide derivatives (M2-M4). These dimers were investigated as new stabilizers for nitrocellulose. The evaluation process has been performed through Bergman-Junk (BJ) test, thermal analysis measurements (TGA and DSC) and kinetic parameters calculations (E(a)). The comparative study between mass spectra and thermal analysis of the new dimers helped in resolving the thermal decomposition mechanisms for the new dimers. It was found that the new dimers especially (MA2 and MA4) showed better stabilizing effect for the nitrocellulose than the centralite 1 (C1) which is the common stabilizer.
Collapse
Affiliation(s)
- M A Hassan
- Fire and Explosion Protection Department, National Institute for Standards, P.O. Box 136, Code 12211 Giza, Egypt.
| |
Collapse
|
40
|
Mahfouz NM, Hassan MA. Synthesis, chemical and enzymatic hydrolysis, and bioavailability evaluation in rabbits of metronidazole amino acid ester prodrugs with enhanced water solubility. J Pharm Pharmacol 2001; 53:841-8. [PMID: 11428660 DOI: 10.1211/0022357011776199] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
A series of amino acid esters (3a-e) have been synthesized and evaluated as potential prodrugs of metronidazole with the aim of improving aqueous solubility and therapeutic efficacy. The aqueous solubility and the lipophilicity (expressed as the log P value) of metronidazole and its esters were investigated. In general the prodrugs revealed enhanced water solubility compared with metronidazole. N,N-diethylglycinate hydrochloride (3a) and 4-ethylpiperazinoacetate (3e) derivatives displayed higher aqueous solubility, which exceeded that of the parent drug by factors of approximately 140 and 100, respectively. All the esters revealed lower log P values than metronidazole except for the 4-phenylpiperazinoacetate derivative (3f), which was 6.5-times more lipophilic than metronidazole. The hydrolysis kinetics of the esters were studied in aqueous phosphate buffer (pH 7.4) and 80% human plasma at 37 degrees C. In all cases the hydrolysis followed pseudo-first-order kinetics and resulted in a quantitative reversion to metronidazole as evidenced by HPLC analysis. The prodrugs exhibited adequate chemical stability (half-life, t1/2, 4-16 h) in aqueous phosphate solution of pH 7.4. In 80% human plasma they were hydrolysed within a few minutesto metronidazole. The esters 3d (methylpiperazinoacetate derivative) and 3f were exempted since their t1/2 values were approximately 2.5 and 8.5 h, respectively. A comparative pH-rate profile study of N,N-diethylglycinate hydrochloride (3a) and 4-ethyl-piperazinoacetate (3e) derivatives in aqueous buffer solution over the pH range 2.2-10 was investigated. The results indicated that 3a showed marked stability at pH 2-6 followed by accelerated hydrolysis at pH 7.4. The basic ester 3e was found to be less stable at lower pH values but exhibited comparative stability at physiological pH. Moreover, in-vivo experiments in rabbits revealed a higher metronidazole plasma level with sustained release characteristics within the prodrug-treated animals (10- and 2.5-fold) as compared with the parent drug-treated group. In conclusion, the designed amino acid esters 3a and 3c-e might be considered as good candidates for water-soluble prodrug forms of metronidazole.
Collapse
Affiliation(s)
- N M Mahfouz
- Department of Pharmaceutical Medicinal Chemistry, Faculty of Pharmacy, Assiut University, Egypt.
| | | |
Collapse
|
41
|
Abstract
Five malonanilide derivatives (M1-M5) were prepared by the reaction of ethyl malonate with aniline derivatives. These compounds were investigated as new stabilizers for double-base propellants (DBPs). The evaluation process has been performed through thermal stability tests, thermal analyses measurements (TGA and DSC) and kinetic parameters calculations (E(a)). The results of the new stabilizers were compared with the results of the classical stabilizer N, N-diethyldiphenyl urea. It has been found that o- and p-dinitromalonanilides, in particular, showed better stability effect for DBPs than the classical one.
Collapse
Affiliation(s)
- M A Zayed
- Chemistry Department, Faculty of Science, Cairo University, Cairo, Egypt.
| | | | | |
Collapse
|
42
|
Abstract
Solid dispersion and crystallization of a very slightly water-soluble drug, allopurinol, were prepared using urea, sodium salicylate and beta-cyclodextrin (beta-CD) as carriers. The spectroscopic infra-red (IR), differential scanning calorimetry (DSC) and powder X-ray diffractometry (PXRD) data indicate a role of these carriers in decreasing the crystallinity of allopurinol and complexing abilities. Solid dispersion and crystallization of the drug with these carriers were used in suppository formulations to investigate their role in enhancement of drug release through the membrane barrier. The bases used included Suppocire AM and the mixture of polyethylene glycols (PEGs). The release rates of allopurinol from lipophilic and hydrophilic suppository bases were examined and compared with those obtained for their inclusion compounds incorporated in the same bases. The prepared suppositories were evaluated for in-vitro drug release, when fresh and on storage. The release of pure allopurinol from the lipophilic base was remarkably higher than that from the hydrophilic one. The release of allopurinol from lipophilic as well as hydrophilic bases was significantly enhanced by crystallization of the drug from 5% w/v of sodium salicylate. Allopurinol crystallized from sodium salicylate, showed enhanced release reaching about 100% in 1 h from the Suppocire AM base. The obtained data from these experiments proved the superiority of the PEG formulations containing coevaporates of the drug to sodium salicylate, ratio 1:1, or of the drug to beta-CD, ratio 1:2; T(90%),12 and 36 min, respectively. A significant decrease of uric acid excretion in rabbits was observed after rectal administration of suppositories containing allopurinol crystallized from sodium salicylate.
Collapse
Affiliation(s)
- E M Samy
- Deptartment of Industrial Pharmacy, Faculty of Pharmacy, Assiut University, Assiut, Egypt
| | | | | | | |
Collapse
|
43
|
Abstract
This study involves the production of short-chain organic acids from kitchen wastes as intermediates for the production of biodegradable plastics. Flasks, without mixing were used for the anaerobic conversion of the organic fraction of kitchen wastes into short-chain organic acids. The influence of pH, temperature and addition of sludge cake on the rate of organic acids production and yield were evaluated. Fermentations were carried out in an incubator at different temperatures controlled at 30 degrees C. 40 degrees C, 50 degrees C, 60 degrees C and uncontrolled at room temperature. The pH was also varied at pH 5, 6, 7, and uncontrolled pH. 1.0 M phosphate buffer was used for pH control, and 1.0 M HCl and 1.0 M NaOH were added when necessary. Sludge cake addition enhanced the rate of maximum acids production from 4 days to 1 day. The organic acids produced were maximum at pH 7 and 50 degrees C i.e., 39.84 g/l on the fourth day of fermentation with a yield of 0.87 g/g soluble COD consumed, and 0.84 g/g TVS. The main organic acid produced was lactic acid (65-85%), with small amounts of acetic (10-30%), propionic (5-10%), and butyric (5-20%) acids. The results of this study showed that kitchen wastes could be fermented to high concentration of organic acids, which could be used as substrates for the production of biodegradable plastics.
Collapse
Affiliation(s)
- C W Loh
- Department of Chemical and Environmental Engineering, Universiti Putra Malaysia
| | | | | | | |
Collapse
|
44
|
Abstract
The application of membrane separation in palm oil refining process has potential for energy and cost savings. The conventional refining of crude palm oil results in loss of oil and a contaminated effluent. Degumming of crude palm oil by membrane technology is conducted in this study. The objective of this research is to study the feasibility of membrane filtration for the removal of phospholipids in the degumming of crude palm oil, including analyses of phosphorus content, carotene content free fatty acids (as palmitic acid), colour and volatile matter. A PCI membrane module was used which was equipped with polyethersulfone membranes having a molecular weight cut off of 9,000 (type ES209). In this study, phosphorus content was the most important parameter monitored. The membrane effectively removed phospholipids resulting in a permeate with a phosphorus content of less than 0.3 ppm The percentage removal of phosphorus was 96.4% and was considered as a good removal. Lovibond colour was reduced from 27R 50Y to 20R 30Y. The percentage removal of carotene was 15.8%. The removal of colour was considered good but the removal of carotene was considered insignificant by the membrane. Free fatty acids and volatile matter were not removed. Typical of membrane operations, the permeate flux decreased with time and must be improved in order to be adopted on an industrial scale. Membrane technology was found to have good potential in crude palm oil degumming. However, an appropriate method has to be developed to clean the membranes for reuse.
Collapse
Affiliation(s)
- K K Ong
- Department of Chemical and Environmental Engineering, Universiti Putra Malaysia, Selangor
| | | | | | | |
Collapse
|
45
|
Tang SN, Fakhru'l-Razi A, Hassan MA, Karim MI. Feasibility study on the utilization of rubber latex effluent for producing bacterial biopolymers. Artif Cells Blood Substit Immobil Biotechnol 1999; 27:411-6. [PMID: 10595441 DOI: 10.3109/10731199909117712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Rubber latex effluent is a polluting source that has a high biochemical oxygen demand (BOD). It is estimated that about 100 million liters of effluent are discharged daily from rubber processing factories. Utilization of this effluent such as the use of a coupled system not only can reduce the cost of treatment but also yield a fermentation feedstock for the production of bioplastic. This study initially was carried out to increase the production of organic acids by anaerobic treatment of rubber latex effluent. It was found that through anaerobic treatment the concentration of organic acids did not increase. Consequently, separation of organic acids from rubber latex effluent by anion exchange resin was examined as a preliminary study of recovering acetic and propionic acids. However, the suspended solids (SS) content in the raw effluent was rather high which partially blocked the ion-exchange columns. Lime was used to remove the SS in the rubber latex effluent. After the lime precipitation process, organic acids were found to adsorb strongly onto the anion exchange resin. Less adsorption of organic acids onto the resin was observed before the lime precipitation. This was probably due to more sites being occupied by colloidal particles on the resin thus inhibiting the adsorption of organic acids. The initial concentration of organic acids in the raw effluent was 3.9 g/L. After ion exchange, the concentration of the organic acids increased to 27 g/L, which could be utilized for production of polyhydroxyalkanoates (PHA). For PHA accumulation stage, concentrated rubber latex effluent obtained from ion exchange resins and synthetic acetic acid were used as the carbon source. Quantitative analyses from fed batch culture via HPLC showed that the accumulation of PHA in Alcaligenes eutrophus was maximum with a concentration of 1.182 g/L when cultivated on synthetic acetic acid, corresponding to a yield of 87% based on its cell dry weight. The dry cell weight increased from 0.71 to 1.67 g/L. On the other hand, using concentrated rubber latex effluent containing acetic and propionic acids resulted in reduced PHA content by dry weight (14%) but the dry cell weight increased from 0.49 to 1.30 g/L. The results clearly indicated that the cells grow well in rubber latex effluent but no PHA was accumulated. This could be due to the high concentration of propionic acid in culture broth or other factors such as heavy metals. Thus further work is required before rubber latex effluent can be utilized as a substrate for PHA production industrially.
Collapse
Affiliation(s)
- S N Tang
- Department of Chemical and Environmental Engineering, Faculty of Engineering, Universiti Putra Malaysia
| | | | | | | |
Collapse
|
46
|
Lai LS, Fakhru'l-Razi A, Idris A, Hassan MA. The performance and kinetic study of membrane anaerobic system in treating POME. Palm oil mill effluent. Artif Cells Blood Substit Immobil Biotechnol 1999; 27:469-74. [PMID: 10595450 DOI: 10.3109/10731199909117721] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The application of the three known kinetic models on MAS (membrane anaerobic system) process treating the POME and the overall MAS treatment efficiency were investigated. The MAS consists of a cross-flow ultrafiltration membrane (Model Micro 240) for solid-liquid separation. Six steady states were attained over a range of mixed liquor suspended solids of 12,681 - 30,460 mg/l. The study showed a good fitting of the Monod Model (91.1%), Contois Model (98.5%) and Chen and Hashimoto Model (95%) for the MAS treating raw POME at organic loadings between 1.5 kgCOD/m3/d to 6.5 kgCOD/m3/d. The growth yield coefficient, Y, was found to be 0,604 kg VSS/kgCOD while the specific microorganism decay rate was 0.099 day(-1). The k values were in the range of 0,242 to 0.425 mg COD/mg VSS.d and the microm values were between 0.145 to 0.257 day(-1). Throughout the study, the removal efficiency of COD was 83.2 to 97.97%. The methane production rate was between 0.262 to 0.473 l/g-COD-utilised/d. The MAS treatment efficiency was greatly affected by SRT and OLRs. In the study, membrane fouling and polarization at the membrane surface played a significant role in the formation of the strongly attached cake layer limiting membrane permeability
Collapse
|
47
|
Abstract
BACKGROUND Thyroidectomy for a large goitre carries a relatively high risk of postoperative respiratory obstruction which may necessitate tracheostomy. METHODS One hundred and three patients with a large goitre who underwent thyroidectomy were studied prospectively. The presence or absence of six preoperative predictive factors for the development of serious postoperative respiratory obstruction was recorded. These factors were: goitre for more than 5 years, preoperative recurrent laryngeal nerve palsy, significant tracheal narrowing and/or deviation, retrosternal extension, difficult endotracheal intubation and thyroid cancer. Tracheostomy was performed on the basis of clinical judgement. RESULTS Postoperative respiratory complications occurred in 32 patients (31 per cent), and were obstructive in 24 patients and not obstructive in eight. Tracheostomy was necessary in 13 patients (13 per cent). Tracheomalacia was the most common indication (n = 5). There were no deaths. At least four of the six risk factors were present in nine of the 13 patients who underwent tracheostomy compared with two of the 90 patients who did not. CONCLUSION Multiple preoperative risk factors in a patient with a large goitre may be useful in predicting the need for planned tracheostomy following thyroidectomy.
Collapse
|
48
|
Abstract
A number of 2,5-disubstituted-1,4-benzoquinone derivatives were prepared and characterized by elemental analysis, infrared (IR), nuclear magnetic resonance (1H-NMR), and mass spectra (MS). These compounds and their synthetic precursors were evaluated for their in vitro antimicrobial and cytotoxic activity. The most potent antimicrobial compound was the thiadiazolyl derivative 4b, which was 2- to 4 times more active than the antimicrobial drug sulfathiazole. All the tested compounds were active in the Brine Shrimp Lethality (BS) Test. Compound 4e which was the most active in the BS test was also found to possess a significant cytotoxicity against two tumor cell lines. Some of the compounds were found to be mutagenic at relatively high concentration.
Collapse
Affiliation(s)
- M A Hassan
- Department of Medicinal Chemistry and Pharmacognosy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | | | | | | | | |
Collapse
|
49
|
Rosfarizan M, Ariff AB, Hassan MA, Karim MI. Kojic acid production by Aspergillus flavus using gelatinized and hydrolyzed sago starch as carbon sources. Folia Microbiol (Praha) 1998; 43:459-64. [PMID: 9867479 DOI: 10.1007/bf02820791] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Direct conversion of gelatinized sago starch into kojic acid by Aspergillus flavus strain having amylolytic enzymes was carried out at two different scales of submerged batch fermentation in a 250-mL shake flask and in a 50-L stirred-tank fermentor. For comparison, fermentations were also carried out using glucose and glucose hydrolyzate from enzymic hydrolysis of sago starch as carbon sources. During kojic acid fermentation of starch, starch was first hydrolyzed to glucose by the action of alpha-amylase and glucoamylase during active growth phase. The glucose remaining during the production phase (non-growing phase) was then converted to kojic acid. Kojic acid production (23.5 g/L) using 100 g/L sago starch in a shake flask was comparable to fermentation of glucose (31.5 g/L) and glucose hydrolyzate (27.9 g/L) but in the 50-L fermentor was greatly reduced due to non-optimal aeration conditions. Kojic acid production using glucose was higher in the 50-L fermentor than in the shake flask.
Collapse
Affiliation(s)
- M Rosfarizan
- Department of Biotechnology, Universiti Putra Malaysia, Selangor
| | | | | | | |
Collapse
|
50
|
Hassan MA, Shabsoug BM. Synthesis of 2-[4-(4-iodophenyl)-1-piperazinylmethyl]-1,3,4-oxadiazole and its potential application in the indirect iodination of carbonyl compounds. Acta Pharm Hung 1997; 67:263-6. [PMID: 9423297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The synthesis of 2-[4-(4-iodophenyl)-1-piperazinylmethyl]- 1,3,4-oxadiazole is discussed. Hydrolysis of the oxadiazole followed by condensation with 3 beta-hydroxy-5-androsten-17-one gave the hydrazone. This synthetic sequence could be applied for the indirect iodination/radioiodination of ketosteroids.
Collapse
Affiliation(s)
- M A Hassan
- Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | | |
Collapse
|