93 results on '"Hassan, Akram"'
Search Results
2. Pharmacological Action and Research Progress of Taraxasterol
- Author
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Zhang, Yu, primary, Shaari, Ramizu Bin, additional, Awang Nawi, Mohamad Arif Bin, additional, Hassan, Akram Bin, additional, and Cui, Caiyun, additional
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- 2024
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3. Ischemic Stroke Secondary to Bleach Anaphylaxis
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Rafey Rehman, Muhammad Osto, Hassan Akram, and Adil Khan
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Ischemic Stroke ,Anaphylaxis ,Bleach exposure ,Cerebral Infarct ,Medicine - Abstract
Anaphylaxis is a severe allergic reaction characterized by life-threatening airway, breathing, and hemostatic problems. There has been an established association between cerebral infarction following wasp or bee sting in the literature. A 54-year-old female was admitted to the hospital for acute anaphylaxis due to bleach exposure and developed a new-onset left-sided weakness. Head computed tomography demonstrated midline frontal calcifications but was negative for acute ischemia or hemorrhage. Magnetic resonance imaging multifocal infarcts of the internal capsule’s right temporal and posterior limb. The patient was started on aspirin 81 mg, atorvastatin 40 mg daily for secondary prevention of stroke, and physical, occupational, and speech therapies. Although exceedingly rare, decreased cerebral blood flow may occur secondary to anaphylaxis due to an abrupt drop in blood pressure leading to ischemic injury. The case characterizes a unique association between bleach anaphylaxis and ischemic stroke, which has not been previously reported.
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- 2022
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4. A Review of Bacterial Colonization on Dental Implants With Various Hygiene Instruments
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Chen, Ashmita, primary, Ghaffar, Hareem, additional, Taib, Haslina, additional, and Hassan, Akram, additional
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- 2023
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5. A Democratic Theory of Life
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Asenbaum, Hans, primary, Chenault, Reece, additional, Harris, Christopher, additional, Hassan, Akram, additional, Hierro, Curtis, additional, Houldsworth, Stephen, additional, Mack, Brandon, additional, Martin, Shauntrice, additional, Newsome, Chivona, additional, Reed, Kayla, additional, Rice, Tony, additional, Torres, Shevone, additional, and Wilson II, Terry J., additional
- Published
- 2023
- Full Text
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6. On an integrodifferential equation in three variables on time scales.
- Author
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Shwish, Khaled and Hassan, Akram
- Subjects
- *
INTEGRO-differential equations - Abstract
In this work, Banach fixed point theorem is used to prove the existence and uniqueness for solving certain integrodifferential equations in three variables on time scales. Moreover, integral inequality with an explicit estimate has been derived and used to study the estimate of the difference between two approximate solutions and the closeness of the solutions for the problem under investigation. [ABSTRACT FROM AUTHOR]
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- 2023
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7. Surgical laser oral depigmentation procedure: an investigation on the optimum power settings using Er:YAG laser
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Stas, Yasser, Hassan, Akram, Noor, Nor FaridMohd, Samsudin, A. R., and Shaari, Ramizu
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- 2018
- Full Text
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8. Effects on the Titanium Implant Surface by Different Hygiene Instrumentations: A Narrative Review
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Yen Nee, Wong, primary, Raja Awang, Raja Azman, additional, and Hassan, Akram, additional
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- 2022
- Full Text
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9. Surgical Intervention on Drug-Influenced Gingival Enlargement using Diode Laser Therapy
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Sabarudin, Muhammad Annurdin, primary, Beh, Yew Hin, additional, Hassan, Akram, additional, Ab Ghani, Zuryati, additional, and Taib, Haslina, additional
- Published
- 2022
- Full Text
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10. Neutral zone concept for implant placement in mandibular overdentures: a case report
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AL-Oulabi, Ayman, primary, Johari, Yanti, additional, Husein, Adam, additional, Hassan, Akram, additional, Shaari, Ramizu, additional, and Ariffin, Azirrawani, additional
- Published
- 2022
- Full Text
- View/download PDF
11. TikTok as a Source of Dermatologic Information on Atopic Dermatitis
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Rafey, Rehman, Sazid, Hasan, Hassan, Akram, and Marla, Jahnke
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Humans ,Immunology and Allergy ,Dermatologic Agents ,Dermatology ,Social Media ,Dermatitis, Atopic - Published
- 2022
12. Concentration Risk Analysis of Commercial Banks and its Relation with GDP and GNI: Comparison of Islamic and Conventional Banks in Pakistan
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Afshan Noreen, Hassan Akram, Khalil ur Rahman, and Economics Pakistan
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Cultural Studies ,Relation (database) ,Religious studies ,Economics ,Concentration risk ,Islam ,Monetary economics - Published
- 2018
13. A Holistic Data Driven Approach for Condensate Recovery Factor Estimation in Gas Condensate Reservoirs
- Author
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Agha Hassan Akram, Salman Zahid, Muhammad Yousuf, Waqar A. Khan, Imtiaz Ali Memon, Hamza Ali Mirza, Abdur Rahman Shah, and Talha Zubair
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Estimation ,Petroleum engineering ,Environmental science ,Data-driven - Abstract
Gas-condensate reservoirs exhibit complex multi-phase flow behavior below saturation pressures resulting from compositional variations. Below saturation pressure, condensate starts dropping-out within the reservoir and eventually develops a bank in the near wellbore region; effectively reducing the relative permeability to gas flow. As a result, production of main phase (gas) decreases with development of this bank while condensate is left behind in the reservoir. Since, reserves estimation is a part of the development plans of all fields, it is important to account for condensate drop-out while deriving a condensate recovery factor during the initial stage of the life of a reservoir. Otherwise a high condensate recovery factor (if assumed equal to or close to that of gas phase) might result in unrealistic optimistic cash flow projections. Given the importance of condensate recovery factor estimation, a data driven analytical method has been developed and will be discussed in detail in this paper; while overcoming the limitation of available data for green fields. An analytical methodology has been developed for calculation of condensate recovery factor in gas condensate reservoirs in the absence of a constant volume depletion (CVD) study laboratory report. The method uses either a linear or a non-linear correlation-based relationship between condensate drop-out and pressure. This enables derivation of an equation for calculation of condensate recovery factor while incorporating critical parameters such as dew point pressure, initial and abandonment pressures and condensate gas ratios (CGRs) at initial and abandonment conditions. A stepwise procedure will be described to derive all these parameters with limited available data in the early stages of the life of reservoir. The methodology adopted was applied to more than 30 green and brown gas condensate fields with varying CGR's. For a few mature fields, results derived from the proposed methodology were compared with recovery factors estimated from numerical simulation models. Results of both approaches appeared to be in a good agreement with an accuracy of +/−10%. As expected, recovery factors derived assuming a simple linear decline of CGR with pressure were less accurate than those calculated using a non-linear correlation-based decline of CGR with pressure. For richer gas condensate fields with high compressibility factors, the z-factor was incorporated with pressure in the form of P/z, which resulted in a more accurate estimation of recovery factors. A comparison has been made where recovery factors are estimated from the described approach and the other reference approaches; and conclusions drawn from these comparisons are discussed. Various approaches have been used historically for condensate recovery factor estimation while relying heavily on a good amount of data available. A simple analytical approach has been discussed which mitigates the impact of poor data availability especially in green fields and yet can yield useable condensate recovery factor calculations. This enables better reserve estimation of condensates in gas condensate reservoirs in early stages of life of reservoirs, while leading to efficient and realistic field development plans in futures.
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- 2020
14. Standardization of Inactive Wells Audit Process for Well Abandonment and Production Enhancement Candidate Screening
- Author
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Elin Haryanto, Saltanat Yersaiyn, Francois Bouchet, Haytham Galal, Mohd Ashraf Basarudin, and Agha Hassan Akram
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Standardization ,business.industry ,Computer science ,Abandonment (emotional) ,Production (economics) ,Operations management ,business ,Risk management ,Audit process - Abstract
The reservoir management team is often facing a standardization challenge during audit and screening of inactive wells, especially if this task involves multiple mature oil reservoirs or fields. Such a well candidate screening process is normally required to select candidates for revival as well as plug and abandonment (P&A) candidates. Shut-in wells across different fields may be sharing common issues such as pressure depletion, liquid loading, and high water cut, however, the severity of well-related problems varies from one field to the other. This is in addition to the variation of wellbore mechanical issues such as well-bore integrity, wellbore accessibility, and others. This paper aims to demonstrate a workflow to provide a quantitative ranking of wells. It can be used to standardize an audit process during multi-reservoir or multi-field inactive-well candidate screening study. The standardization process was addressed by developing a tool that registers the shut-in well ranking upon completing the well potential and risk assessment process. Well level petroleum engineering and production data analysis such as decline curve analysis, nodal analysis and well modeling are performed to estimate the remaining well potential. Subsequently, to enable a comparison across different fields, behind pipe well potential was normalized using multi-field parameters. The audit process followed with well workover risking based on ease of workover intervention including workover options such as water shut off, remedial wellbore integrity work, stimulation and others where it also draws on local knowledge for well risk calculation. The approach presented in this study provides a comprehensive tool for both key performance indicators; remaining well potential and well risk, that are usually required to short-list wells for workovers. The standardized audit process was demonstrated in a case study where a large number of shut-in wells from multiple mature oil fields were ranked. In this study, the 7 highest ranked wells were recognized as production enhancement candidates and conversely, a number of wells with the lowest ranking were identified for well abandonment. Through this standardized workflow, the well risk assessment was performed efficiently with tools that enable a consistent result across different fields. It helped to accelerate the reservoir management decision-making process in identifying wells with the most impact to increase the success probability during inactive well revival and workover. The workflow and the tool presented in this paper has the potential to be used as analytic tool or template and can be used as a live document that may be adopted to reduce the workload and improve shut-in well management.
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- 2019
15. Impact of Loan Quality, Funding Management and Asset Quality on Liquidity Risk Management of Pakistani Banks
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Ghulam Abbas, Pakistan Economics, Hassan Akram, and Khalil ur Rahman
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Cultural Studies ,Finance ,Loan ,business.industry ,Asset quality ,media_common.quotation_subject ,Religious studies ,Quality (business) ,Business ,Liquidity risk ,media_common - Published
- 2018
16. Credit risk management: A comparative study of Islamic banks and conventional banks in Pakistan
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Khalil ur Rahman and Hassan Akram
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Economics and Econometrics ,Asset quality ,Financial ratio ,Accounting ,Development ,Credit risk management ,Loan quality ,Dummy variable ,lcsh:Finance ,lcsh:HG1-9999 ,ddc:330 ,Pakistan ,lcsh:BP1-253 ,Risk management ,Descriptive statistics ,business.industry ,lcsh:Islam ,Regression analysis ,Loan ,Conventional banking ,Islamic banking ,business ,Finance ,Credit risk - Abstract
PurposeThis study aims to examine and compare the credit risk management (CRM) scenario of Islamic banks (IBs) and conventional banks (CBs) in Pakistan, keeping in view the phenomenal growth of Islamic banking and its future implications.Design/methodology/approachA sample of five CBs and four IBs was chosen out of the whole banking industry for the study. Secondary data obtained from the banks’ annual financial reports for 13 years, starting from 2004 to 2016, were analyzed. Multiple regression, correlation and descriptive analysis were used in the examination of the data.FindingsThe results show that loan quality (LQ) has a positive and significant impact on CRM for both IBs and CBs. Asset quality (AQ), on the other hand, has a negative impact on CRM in the case of IBs, but has a significantly positive relation with CRM in the case of CBs. The impact of 16 ratios measuring LQ and AQ have also been individually checked on CRM, by making use of a regression model using a dummy variable of financial crises for robust comparison among CBs and IBs. The model proved significant, and CRM performance of IBs was observed to be better than that of CBs. Moreover, the mean average value of financial ratios used as a measuring tool for these variables shows that the CRM performance of IBs operating in Pakistan was better than that of CBs over the period of the study.Practical implicationsThe research findings are expected to facilitate bankers, investors, academics and policy makers to build a better understanding of CRM practices as adopted by CBs and IBs. The findings would be useful in formulating policy measures for the progress of the banking industry in Pakistan.Originality/valueThis research is unique in terms of its approach toward analyzing and comparing CRM performance of CBs and IBs. Such work has not been carried out before in the Pakistani banking industry.
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- 2017
17. Stability: A Report of Two Cases: Bone Gain and Implant Stabilization After Poor Primary and Secondary Implant
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Al-Juboori, Mohammed Jasim, Abdulrahaman, Shafluzan bin, and Hassan, Akram
- Published
- 2012
18. Aggressive angiomyxoma of left buttock
- Author
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Hassan Akram, Rafey Rehman, Zaid Al-Wahab, and Deanna Tran
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Male ,medicine.medical_specialty ,Case Report ,Thigh ,Complete resection ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Aggressive angiomyxoma ,Obstetrics and gynaecology ,Progesterone receptor ,medicine ,Humans ,business.industry ,Incidence (epidemiology) ,General Medicine ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,medicine.anatomical_structure ,Receptors, Estrogen ,030220 oncology & carcinogenesis ,Left buttock ,Buttocks ,Female ,Neoplasm Recurrence, Local ,Differential diagnosis ,business ,Myxoma - Abstract
Aggressive angiomyxoma (AA) is a rare mesenchymal tumour that is characterised by increased incidence in women compared with men, local invasion to the surrounding tissue and high recurrence rate. A premenopausal woman presented to clinic with pelvic pressure, intermittent tingling in the thigh and pressure emptying the bladder. CT scan, vaginal and gluteal biopsies, and MRI scan were performed to conclude a final diagnosis of AA. The patient underwent complete resection of the mass. The mass tested positive for oestrogen receptor and progesterone receptor. The patient received leuprolide postoperatively to prevent recurrence. AA should be considered as a differential diagnosis for a pelvic and perineal mass. Patients should be warned of high recurrence rate, necessity of surgical removal and long-term hormonal treatment.
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- 2021
19. Modelling Complex Fluid Production Behaviour in a Gas Condensate Field: A Case Study
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Abdul Waheed, Waqar A. Khan, Abdur Rahman Shah, Hamza Ali, Fareed Iqbal Siddiqui, Faizan Ahmed, and Agha Hassan Akram
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Field (physics) ,Production analysis ,Environmental science ,Production (economics) ,Field development ,Mechanics ,Complex fluid - Abstract
A recent study addressed the modelling challenges of Alpha* gas condensate field. Alpha gas condensate field has a gas in-place of about 1 TCF, and both condensate and black oil production in addition. The field has been producing from two reservoirs S-I and D-I, for the past 26 years. Alpha field is sub-divided into two segments called the Central Area and the Northern Area which are separated by a fault as shown in Figure 2. * Not its real name.
- Published
- 2019
20. Comparison of C═C Bond Hydrogenation in C-4 Unsaturated Nitriles over Pt/Alumina
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S. David Jackson, Andrew Monaghan, and Hassan Akram
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Zero order ,Nitrile ,010405 organic chemistry ,organic chemicals ,General Chemical Engineering ,Liquid phase ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,Industrial and Manufacturing Engineering ,0104 chemical sciences ,Catalysis ,chemistry.chemical_compound ,chemistry ,Methacrylonitrile ,Organic chemistry ,Amine gas treating ,Allyl cyanide - Abstract
The hydrogenation of allyl cyanide (but-1-ene-4-nitrile, AC), trans- and cis-crotononitrile (E- and Z-but-2-ene nitrile, TCN and CCN), and methacrylonitrile (2-cyano-1-propene, MCN) were studied, both singly and competitively, over a Pt/alumina catalyst in the liquid phase. Each unsaturated nitrile only underwent C═C bond hydrogenation: no evidence was found for the formation of the saturated or unsaturated amine. The nonconjugated allyl cyanide was found to be the most reactive unsaturated nitrile. Activation energies for the hydrogenation of the C═C bond in AC and MCN were determined giving values of 64 ± 7 kJ mol–1 for AC and 37 ± 4 kJ mol–1 for MCN. The reaction was zero order for both nitriles. Competitive hydrogenations revealed that not only does allyl cyanide react preferentially over the other isomers but also it inhibits the hydrogenation of the other isomers. When all four nitriles were simultaneously hydrogenated, inhibition effects were easily seen suggesting that in terms of strength of bonding to the surface an order of AC > CCN > TCN ∼ MN can be generated.
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- 2016
21. Effects of Different Prophylaxis Procedures on Titanium Implant Fixture: A Scanning Electron Microscopy Study.
- Author
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Bahari, Zul Fahmi, Raja Awang, Raja Azman, and Hassan, Akram
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SCANNING electron microscopy ,TITANIUM ,AIR flow ,PREVENTIVE medicine - Abstract
This study aimed to describe the effects of different prophylaxis procedures on titanium implant fixture surfaces under Scanning Electron Microscopy (SEM). Fifteen BEGO Semados® implant fixtures were mounted on stone stands and randomly divided into 3 groups which were Control (C) (n=5), Air Flow (AF) (n=5) and Rubber Cup with Pumice Powder (RC) respectively. After 2 minutes of prophylaxis procedures, all treated samples were irrigated with normal saline and fixed with 2.5% glutaraldehyde. They were air dried, wrapped and stored in individually labeled and sealed compartments. One fixture was randomly selected from each group and they were observed under SEM at x1000 and x2000 magnifications. SEM showed that surfaces from C group displayed machine lines due to milling process with minimal pits and scratches. The surfaces from AF group had generalized micro pits and pores with the machine lines still observed. In RC group, the surfaces demonstrated homogeneous line of scratches that identical to the rotational movement of the RC. The machining marks and lines were also disappeared. Based on the findings, the titanium implant fixture surfaces treated with RC revealed less invasive and more effective compared to AF. [ABSTRACT FROM AUTHOR]
- Published
- 2021
22. Colonization of Streptococcus mutans on Titanium Implant Abutment with Different Hygiene Instruments under Scanning Electron Microscopy.
- Author
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Shahbudin, Najahhuddin, Mohamad, Suharni, and Hassan, Akram
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STREPTOCOCCUS mutans ,SCANNING electron microscopy ,SCANNING electron microscopes ,BACTERIAL colonies ,HYGIENE - Abstract
This study was aimed to describe the differences in amounts of Streptococcus mutans (S. mutans) colonization on the titanium-implant abutment surfaces after treatment with two different hygiene instruments by using Scanning Electron Microscope (SEM). Fifteen Dentium Combi titanium-implant abutments were randomly divided equally into three groups. Five abutments were selected for untreated/control (C) group and the other two groups which were treated with rubber cup with pumice powder (RC) and air polishing (AP) respectively. S. mutans was then cultured on untreated and treated specimens. One sample from each group was randomly selected and observed for the bacterial colonization on the surface of abutment using SEM. At x2000 magnification, the machining marks were observed in C and AP groups whereas the surface was smoothened in RC group. Sparse colonies could be observed in both C and RC groups but moderate colonies was noticed in AP group at a magnification of x5000. At x10 000 magnification, multilayers of bacterial chains could be seen in C and AP groups, while a monolayer of bacterial chain was found in RC group. RC instrumentation revealed lesser amounts of S. mutans colonization compared to instrumentation with AP. [ABSTRACT FROM AUTHOR]
- Published
- 2020
23. Effect of genetics and leaves spraying with arginine and yeast acid on some of the characteristics of Solanum tuberosum L.): تأثير التركيب الوراثي والرش الورقي بحامض الارجنين والخميرة في 2- بعض صفات حاصل البطاطا (Solanum tuberosum L.)
- Author
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Aziz Mahdi Abdul Shammari, Zainab Hassan Akram, and Atheer Abdul
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Arginine ,fungi ,Botany ,food and beverages ,Biology ,Solanum tuberosum ,Yeast - Abstract
Field experiment was conducted in the hand of the HIBHIB vast area in the Diyala province. During the spring season in 2015 to study Tothiratlath genotypes of potatoes which Emma and Rivira and Loane six transactions of Foliar acid arginine and a yeast; spraying a solution of acid arginine concentration of 200 Melgm.ltr-1, spray a solution of acid arginine concentration of 300 Melgm.ltr1-, spraying a solution of yeast concentration of 5 Gm.ltr-1, spraying a solution of a mixture of acid arginine concentration of 200 Melgm.ltr-1 and yeast solution concentration of 5g. ltr-1. to ratio of 1: 1, spraying a solution of a mixture of acid arginine concentration of 300 Melgm.ltr-1 and yeast solution 5 Gm.ltr-1 1: 1 ratio and the treatment comparison (spraying with distilled water). The experiment carried out in accordance with the system of panels splinters split plot design using RCBD and three replications, tested moral differences between the averages of the traits studied according to Duncan test and the level of probability of 0.05. The study showed superiority installation Rivira highest average weight of the tuber and the weight of the largest tuber and best quotient per plant and the best quotient whole. As for the impact sprinkler transactions plants lost all plants outperformed sprayed on the plants is sprayed and characterized the plants sprayed with a mixture of yeast and acid arginine concentration of 200 Melgm.ltr-1 highest the number of tubers and outperformed the treatment of yeast and acid arginine concentration of 300 Melgm.ltr-1 on the treatment of comparison where gave a higher quotient per plant, and excelled genotype Rivira plants sprayed with yeast and acid arginine 300 Melgm.ltr-1 best number of tubers, as well as genotype Loane sprayed with a mixture of yeast plants acid arginine concentration of 300 Melgm.ltr-1 higher weight to larger tuber, while installation Emma plants sprayed with yeast recorded the highest percentage of dry matter.
- Published
- 2017
24. EFFECT OF DRINKING WATER QUALITY ON PHYSIOLOGICAL BLOOD PARAMETERS AND PERFORMANCE OF LAYING HENS IN DIYALA PROVINCE, IRAQ.
- Author
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Hassan, Akram Ahmed, Hameed, Marah Salim, and Ali Al-Ezzy, Ali Ibrahim
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DRINKING water quality ,HENS ,ELECTRIC conductivity ,BLOOD serum analysis ,BODY weight - Abstract
Current objectives to evaluate the influences of drinking water quality on blood parameters and performance of ISA brown laying hens. Total of 6000 ISA brown layers of 200 day-old weighing 1.4 to 1.7 kg from three different farms in average of 2000 ISA brown hens per farm that utilize Agricultural drainage water, river water and tap water for drinking were put under investigation. Three samples of drinking water were collected from each source in hens house (agricultural drainage water; river water and tap water) at 15 days interval. Each time samples analyzed directly to determine turbidity (Nephelometric turbidity unit, NTU) (NTU), PH and electric conductivity. Three samples of blood were collected from wing vein at 15 days interval using EDTA free tubes for collection of serum to determine Serum Chloride, Sodium, Phosphor, Calcium and potassium . Productive Performance evaluated by determination of.egg weight, Hen day Mortality, body weight and food consumption were determined at 15 days interval. Significant difference, p value (0.001624) between three types of waters regarding turbidity (Nephelometric turbidity unit, NTU) (NTU); PH, p value (0.030139) and electric conductivity, p value (0.0000808). There was no significant difference in the serum level of Sodium, Chloride, Calcium, Phosphor, potassium, BUN and Creatinine of ISA brown drinks river water, agricultural drainage water and tap water. ISA brown drinks tap water have no mortality for the entire time of the study, higher hen day, higher food consumption, higher body weight and egg weight compared with other types of water with significant difference between them, p value = (<0.0001). Quality of drinking water has accumulative effects on blood parameters and direct effect on performance of ISA brown laying hens. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
25. The Psychological Impact of Foetal Loss at Term on Sudanese Mothers
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Hassan, Akram Elkhier, primary
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- 2018
- Full Text
- View/download PDF
26. Correlation between Ultrasound Findings of Ectopic Pregnancy And Operative Findings in Sudanese Women
- Author
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Hassan, Akram Elkhier, primary
- Published
- 2018
- Full Text
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27. Effects of Economic Analysis on Re-Developent of a Gas Field – Lessons Learned from a Reservoir Simulation Study
- Author
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Arshad Majeed, Zaid Ashraf, Waqar Ali Khan, Agha Hassan Akram, and Shah Abdur Rahman
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Natural gas field ,Reservoir simulation ,Petroleum engineering ,Environmental engineering ,Economic analysis ,Environmental science - Abstract
The subject Gas Field is located in the Sulaiman Fold Belt (SFB) in Pakistan. A realistic 3D static model was constructed for the challenging multiple reservoirs in the Field which included both clastics and carbonates. Four main reservoir horizons were modeled. The steps involved in the Reservoir engineering analyses were: analyze PVT, well test, Static Pressure Data, and Core. The static pressure analysis helped define hydraulic compartmentalization in the field. WHFP measurements were not available in the desired accuracy and density. A surface network model was used with plant inlet pressure as the primary constraint in order to obtain the required information. Satellite based elevation information was used to establish an accurate model with respect to pressure drop due to liquid hold up in pipelines. The History Match in the field was performed on a Zone by Zone basis. In the absence of a 3D seismic cube, many of the faults in the field could not be interpreted, yet their presence was predicted by a closely matching Sand Box Model. This was an important clue which led to a useful approach regarding the location of simulation faults distributed in the entire field. An innovative approach was used in order to calibrate the size of sand lenses in one of the zones. The final step was the forecasting and development of Optimal Scenario using Economic analysis. Many scenarios were tested, and the optimal scenario was identified. Maximum use was made of existing wellbores through re-completion, and new drilling was minimized. Furthermore, the impact of increasing the currently low Gas Price was tested. It was concluded that doubling of the gas price of the field would increase the NPV 3 times delay abandonment by 6 years.
- Published
- 2012
28. An Improved Model for Wireline Formation Tester Pumpout Time Estimation
- Author
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Waqar Ali Khan, Robert A. Wattenbarger, Agha Hassan Akram, and Syed Shahbir Shah
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Computer science ,Time estimation ,business.industry ,Wireline ,Electronic engineering ,Electrical engineering ,business - Abstract
Wireline formation testers are now in their third generation of development. These tools are used to measure formation pressure andpermeability, and to take fluid samples from the reservoir. Technological developments over the years have resulted in a modular tool that can obtain a clean formation fluid sample with minimal contamination. Sampling time varies from a few minutes to many hours depending upon different parameters i.e. depth of invasion, flow rate, formation permeability, anisotropy, porosity and the viscosity of the involved fluids including mud filtrate and formation fluids. Total pumpout time required to obtain a clean sample is always of interest to both the operator and service company owing to economics, well stability and other factors. An approach is required that is flexible and that requires few parameters to estimate the pumpout time and the time for first formation fluid slug. In this study a new polynomial model is developed to better estimate the time to first slug. The new model was tested for different pumpouts from different wells and history matching was performed to test the accuracy of the model. A number of pumpouts were considered and all of those showed close matches. Software was developed to quickly calculate the total pumpout time at real time. Also in this study the previous model was tested and with the limited available data the new model showed much improved results over the previous model.
- Published
- 2011
29. Production Forecasting in Heterogeneous Reservoirs without Reservoir Simulation
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Aamir Badr, Agha Hassan Akram, and Lawrence A.P. Camilleri
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Reservoir simulation ,Production forecasting ,Petroleum engineering ,Reservoir modeling ,Geology - Abstract
As an increasing percentage of the world’s production comes from mature fields, there is a growing need for production enhancement techniques that are both rapid and easy to use for the practicing production engineers. For mature waterfloods, the ln(WOR) versus Np plot enables rapid well screening on the basis of incremental recovery factor, where WOR is the producing Water Oil Ratio and Np is the cumulative oil production. Published in-depth information on application of this tool is sparse. Yet, this is often the only tool available to the production engineer for evaluating development options, where a history-matched simulation model has not been maintained. In this paper, the theoretical basis for the use of the ln(WOR) versus Np is reviewed and studied, and is used to arrive at practical guidelines for interpreting production data. Its applicability as a forecasting tool to single-layered and multilayered clastic, waterflooded reservoirs of varying heterogeneity is demonstrated. Numerical simulation models then predict the behaviour of this plot for a wide range of heterogeneities. Production data is then analysed to show the applications of the theory for multilayered reservoirs. The ln(WOR) versus Np plots are analysed, and the impact of various factors is observed. The authors also demonstrate that, where applicable, this plot is the preferred decline curve for the following reasons: –Ln(WOR) versus Np does not require any pressure data; only surface well test production history is required.–It can be assumed that the ln(WOR) versus Np function is an approximate function of the reservoir only, and is decoupled from the outflow and facility constraints. This is especially useful when comparing artificial lift and drawdown strategies.–It is a decline curve model that provides a forecast of water cut, which is indispensable on waterflood projects.
- Published
- 2011
30. Combining the Use of ESPs and Distributed Temperature Sensors to Determine Layer Water Cut, PI, and Reservoir Pressure
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Lawrence A.P. Camilleri, Maria Elena Quinzo Bravo, and Agha Hassan Akram
- Subjects
Water cut ,Petroleum engineering ,Chemistry ,Reservoir pressure ,Layer (electronics) ,Remote sensing - Abstract
In many oil wells, production is commingled from several layers. In such environments, understanding the properties of individual layers is essential to reservoir surveillance and production optimization. The inflow properties that typically require measuring are productivity index (PI), water cut, and static reservoir pressure. These measurements have traditionally been taken with wireline-conveyed production logging tools (PLT); however, in many wells and operating environments, completion and logistic considerations make running these tools difficult or even impossible. In those instances, an alternative is required. This paper presents a new procedure based on multirate testing in combination with distributed temperature sensors (DTS), an electric submersible pump (ESP) fitted with a gauge in the commingled fluid stream, and conventional surface testing. The additional test rates provide sufficient equations to resolve all the unknowns, whereas the DTS provides essential information such as which layers are producing and which are taking fluid, as well as a mass flowrate tool for measuring the flow rate of each layer. The procedure requires varying well flow rates over a range sufficient to ensure that all layers are producing, which in many cases requires an ESP to provide sufficient drawdown to overcome crossflow as well as a variable-speed drive to establish the test rates. The theoretical basis for the protocol is described, and an example is detailed to demonstrate the validity and robustness of the method for determining inflow properties. Finally, theoretical and practical guidelines are provided to demonstrate how the test procedure is affected by fiber-optic resolution, fluid properties, and the geothermal gradient. For wells equipped with forms of artificial lift such as ESPs, beam pumps, and progressive cavity pumps (PCPs), running PLTs is often not possible because of the completion obstruction. In such cases, this new DTS-enabled procedure has the potential of becoming the PLT substitute of the future.
- Published
- 2010
31. Dynamic Behavior of a Fissured Dual-Carbonate Reservoir Modeled with DFN
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Alexandru Serban, MAqsood Ali, Mohamed Seragaldin Thabt, Agha Hassan Akram, and Yousef Senussi Gherryo
- Subjects
chemistry.chemical_compound ,chemistry ,Carbonate ,DUAL (cognitive architecture) ,Petrology ,Geology - Abstract
A Paleocene dolomite in northeastern Libya was modeled using three porosity types: matrix porosity (intercrystalline plus the separate vugs), horizontal-to-subhorizontal solution-enlarged vuggy porosity generated by dissolution and named "touching vugs," and fracture porosity. The touching vugs, which acted like fractures in their dynamic behavior, are modeled as a very permeable discrete fracture network (DFN) in PETREL* seismic-to-simulation software. Their presence is known primarily due to pressure buildup analysis, and it is expected that they would be interconnected over hundreds of meters. The primary challenge in dual-media modeling is being able to characterize and predict the dynamic behavior of the complex matrix + fracture + touching vug system. There are three wells in this area of northeastern Libya with pressure buildups that have an unusually distinct and pronounced dual-porosity signature. Each well has been matched by adjusting the five primary parameters: matrix and fracture porosity and permeability, and the sigma shape factor. Aquifer strength also had to be adjusted. There are some aspects of the dynamic behavior of this reservoir that are of particular interest: The highly fractured low-porosity parts of the reservoir are the least productive, and the least fractured high-porosity parts with touching vugs are the most productive.The well test shows pronounced dual-porosity behavior and indicates a high level of contrast between the matrix and secondary porosity systems, both in terms of permeability and porosity.There is a strong aquifer and in reservoirs with moderate fracture permeability, we would expect to see the fractures provide a pathway for rapid water breakthrough. Owing to the very high permeability associated with the fracture system, this does not happen as expected; i.e., the reservoir acts to some extent like a tank with a level oil/water contact (OWC). There is not much coning or advancing of water in the secondary porosity system. This paper presents the dynamic features of the reservoir and demonstrates how the simulation model was calibrated using all available information, in particular, the pressure buildups.
- Published
- 2010
32. Correcting Underestimation of Optimal Fracture Length by Modeling Proppant Conductivity Variations in Hydraulically Fractured Gas/Condensate Reservoirs
- Author
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Agha Hassan Akram and Abdul Samad
- Subjects
Petroleum engineering ,Fracture (geology) ,Geotechnical engineering ,Conductivity ,Geology - Abstract
A study was carried out to forecast the productivity of a hydraulically fractured well in a retrograde gas-condensate sandstone reservoir using a numerical model. The fracture was explicitly modeled as a set of high-conductivity cells. At the gas velocities normally encountered in hydraulic fracture proppant packs, non-Darcy pressure drops dominate, and the apparent proppant permeability is one or two orders of magnitude lower than the Darcy permeability measured at single phase low-rate conditions. This is particularly true if a liquid phase is also flowing. The apparent permeability of the proppant is a function of: Gas velocity (hence: rate and flowing pressure)Ratio of free liquid rate to gas rateStress on the proppantType of proppant Thus, apparent proppant permeability will vary with distance from the wellbore, increasing towards the tip of the fracture where liquid ratio and velocity are lower. This variation of permeability was explicitly modeled in the proppant pack by dividing it into segments and calculating the permeability in each segment. As a result of this modeling, the impact of increased fracture length on productivity was found to be more significant than in simpler modeling where one permeability value is used for the entire proppant pack. The variation of apparent proppant permeability along the length of the fracture and its impact on well productivity are discussed in this paper. A comparison of predicted well productivity is also made with the use of a constant permeability value for the proppant in numerical and analytic simulators. We will show that using a constant proppant permeability value results in an estimate of optimal fracture length that is too short.
- Published
- 2006
33. Addressing Some of the Unique Challenges of Drillstem Tests in Tight Gas Reservoirs
- Author
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Agha Hassan Akram and Mohammed Riaz Khan
- Subjects
Petroleum engineering ,Geology ,Tight gas - Abstract
An innovation in the methodology of conducting drillstem tests (DSTs) in tight gas reservoirs is presented, along with a simplification in the interpretation of the data obtained. DSTs in tight gas reservoirs are a problem because the flow rates are often too low to be measured by conventional equipment. In these cases a normal flowing and buildup test should be followed by a closed chamber test to produce usable estimates of flow rates at various times during the preceding normal flowing and buildup test. This estimated flow rate can then be used to interpret the buildup after the flow testing, which is produced by shutting the downhole valve. In the interpretation of DST data from a tight gas reservoir, factors such as the following have to be considered: 1) large variation of gas properties resulting from the large pressure range involved1,2; 2) flow rate duration that can be many times shorter than the buildup period3,4,5,6; 3) varying flow rate during the flowing part of the test; and 4) impact of boundaries and heterogeneities. We show that a simple interpretation approach with constant flow rates and pseudo-pressure yields results that are within the intrinsic accuracy limits expected from such a test. The benefits to the field interpreter of using the methods presented are 1) operational flexibility: if the well flows strongly enough the rate may be measured at surface; if it does not, a closed chamber test can be added; 2) the benefit of the deeper radius of investigation of a test flowing at surface is retained; 3) field interpretation is simpler whether surface measurement is possible or not.
- Published
- 2005
34. Chloride ion transport in bridge deck concrete under different curing durations
- Author
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Ghanem, Hassan Akram
- Subjects
Steel -- Corrosion ,Bridges -- Design and construction -- Testing ,Ionization ,Chlorides ,Roads -- Testing ,Bridges -- Texas -- Observations ,Concrete -- Permeability - Abstract
The durability of concrete is usually measured by the number of years of maintenance- free service it provides. If a correct prediction has been made of the environmental conditions to which the concrete will be subjected to, concrete can be made to last for its intended service life. The durability of concrete is closely related to its permeability. The permeability dictates the rate at which aggressive agents can penetrate the concrete and attack the steel reinforcement. During winter, ice accumulates on the top surface of concrete slabs and bridge decks. For the purpose of removing the snow and ice, de-icing agents, such as sodium chloride and calcium chloride, are applied. These salts migrate down to the reinforcing steel through small pores in the concrete. Over time, the chlorides in these salts can react with the reinforcing steel, breaking down the passive layer and causing the steel to corrode. In Texas, the specification requirement for wet-mat curing is 8 days for decks with Type I and III cements and 10 days for decks with Type II and I/II cements and for mix designs with fly ash. Once the concrete is cured sufficiently, the deck is allowed to dry for one day. An additional day is typically allowed for any required surface treatment. The main objective of the research is to explore the possibility of opening the bridge decks earlier than 10 to 12 days by decreasing the number of wet mat curing days. For this reason, concrete mixtures typically used in Texas bridge deck were evaluated using numerous tests such as the Ponding test, the Rapid Chloride permeability Test, and the Abrasion Test. This research focuses on the effect of curing on the chloride ion permeability of different mix design. It is expected that the knowledge gained through this work can be used to optimize the number of curing days and age required before full traffic can be allowed on bridge decks in Texas.
- Published
- 2004
35. Multivariate Analysis of Factors Affecting Presence and/or Agenesis of Third Molar Tooth
- Author
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Alam, Mohammad Khursheed, primary, Hamza, Muhammad Asyraf, additional, Khafiz, Muhammad Aizuddin, additional, Rahman, Shaifulizan Abdul, additional, Shaari, Ramizu, additional, and Hassan, Akram, additional
- Published
- 2014
- Full Text
- View/download PDF
36. The Correlation Between Crestal Bone Resorption and Implant Stability During Healing Period Using Resonance Frequency Analysis
- Author
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Jasim Al-Juboori, Mohammed, primary, AbdulRahaman, Shafluzan Bin, additional, and Hassan, Akram, additional
- Published
- 2013
- Full Text
- View/download PDF
37. What is the effect of initial implant position on the crestal bone level in flap and flapless technique during healing period?
- Author
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Al-Juboori, Mohammed Jasim, primary, Ab Rahman, Shaifulizan, additional, Hassan, Akram, additional, Bin Ismail, Ikmal Hisham, additional, and Tawfiq, Omar Farouq, additional
- Published
- 2013
- Full Text
- View/download PDF
38. Main Medical Illness, Oral Health Complaints and Treatment in Elderly Patients Attending Hospital Universiti Sains Malaysia (HUSM) Dental Clinic.
- Author
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Sinor, Mohd Zulkarnain, Ahmad, Basaruddin, Ariffin, Azirrawani, and Hassan, Akram
- Abstract
Objective: The aim of this study was to describe the main oral health and medical problems among elderly patients attending the dental clinic at Hospital USM. Materials and Methods: This cross-sectional study evaluated 98 patients aged 60 years old and above who attended the clinic from 1
st January 2014 to 30th June 2014. Patient's medical record was obtained from the medical record unit and data on sociodemographic, main dental complaints and medical history were recorded. Results: Edentulism (30.6%) is the main reason for dental attendance followed by dental caries (21.4%), mobile tooth (16.3%) and tooth pain (13.3%). Most patients had hypertension (69.4%), diabetes (35.7%) heart disease (20.4%) and musculoskeletal disorder (13.3%). Conclusion: In conclusion, the main reason for dental attendance in the elderly are related to the cause of tooth loss and problems arising from tooth loss. Caution should be exercised when attending to the dental problem in elderly patients due to their medical problems. [ABSTRACT FROM AUTHOR]- Published
- 2018
39. An in vitro genotoxicity study of silver amalgam on Ames test
- Author
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Hassan, Akram, primary, Omar, S.A, additional, and Ariffin, Zaihan, additional
- Published
- 2010
- Full Text
- View/download PDF
40. Arterial stiffness in patients with localized and generalized severe chronic periodontitis: A preliminary study
- Author
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Arief, Erry Mochamad, primary, Khee, Ho Ting, additional, Rehman, Asia, additional, Hassan, Akram, additional, and Khamis, Mohd. Fadhli, additional
- Published
- 2009
- Full Text
- View/download PDF
41. Pre-column dervatization of amino acids from nigella sativa L seed hydrolysates by reversed phase HPLC
- Author
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Mahmoud, Waleed Ali, primary, Dhahir, Saadiyah Ahmed, additional, and Hassan, Akram Yousif, additional
- Published
- 2008
- Full Text
- View/download PDF
42. Substituted Quinolinones. Part 11. Efficient Synthesis of Different 3‐(4‐Arylidene and Hetarylidene‐5‐oxopyrazolin‐3‐yl)quinolin‐2‐ones.
- Author
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Abass, Mohamed, primary, Othman, Elham S., additional, and Hassan, Akram, additional
- Published
- 2007
- Full Text
- View/download PDF
43. Substituted Quinolinones, Part 11: Efficient Synthesis of Different 3‐(4‐Arylidene and Hetarylidene‐5‐oxopyrazolin‐3‐yl) quinolin‐2‐ones
- Author
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Abass, Mohamed, primary, Othman, Elham S., additional, and Hassan, Akram, additional
- Published
- 2007
- Full Text
- View/download PDF
44. PRESERVATION TECHNIQUE FOR EXTERNAL LARYNGEAL NERVE IN THYROID SURGERY
- Author
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A Hassan, Akram, primary, Y Abdul-Wahab, Adnan, additional, and J Mohammed, Nassief, additional
- Published
- 2006
- Full Text
- View/download PDF
45. Intestinal Stomas and their Complications:A Descriptive Study
- Author
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A. Hassan, Akram, primary, Y. Abdul-Wahab, Adnan, additional, and G. Mohammed Redha, Ali, additional
- Published
- 2003
- Full Text
- View/download PDF
46. Evaluation of Different Hygiene Instruments on Titanium Implant Abutment.
- Author
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Hassan, Akram, Taib, Haslina, Abas, Norhayati, Peh Li Zhen, Davina, and Hanafi, Nurhanani Nabilah
- Abstract
Objective: The aim of this study was to describe the titanium implant abutment surface in untreated and treated groups with air powder abrasive system and rubber cup with pumice powder by using Scanning Electron Microscope (SEM). Materials and Methods: Nine Dentium Combi titanium implant abutments were randomly divided equally into three groups. Three abutments were selected for untreated / control group (C) and the other two groups were treated with air powder abrasive system (AF) and rubber cup with pumice powder (RC) respectively. All abutments were mounted to Dentium implant analog embedded in a clear acrylic resin block before instrumentations. The entire surface of abutments were cleaned by two different hygiene instruments for two minutes and fixed with 2.5% glutaraldehyde. One of abutments from each group was selected to be observed under SEM. Results: SEM showed that abutment from C group was not a smooth surface and revealed machine lines due to milling process. The abutment from AF group created a generalized micropores and craters but the machine lines were still observed and intact. Meanwhile the abutment from RC group showed irregular shape and diminished machine lines. Conclusion: The surface topography treated with air powder abrasive system showed more prominent machine lines but with generalized micro pits and pores on the entire abutment surface while the surface topography treated with rubber cup and pumice showed less prominent machine lines with obliterated scratches and pits. [ABSTRACT FROM AUTHOR]
- Published
- 2017
47. SHORT COMMUNICATIONS. Bovine Pericardium: A Highly Versatile Graft Material.
- Author
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Athar, Yousaf, Zainuddin, Siti Lailatul Akmar, Berahim, Zurairah, Hassan, Akram, Sagheer, Aamina, and Alam, Mohammad Khursheed
- Abstract
Background: The qualities of a barrier membrane are integral to the process of guided tissue regeneration (GTR). Biocompatibility, biodegradability, adherence and proliferation of regenerative cells, potential to maintain adequate sealing of the underlying defect, are amongst the properties fundamental to the success of a barrier membrane. Materials: Materials belonging to diverse origins and characteristics have yielded varying degrees of success as graft and barrier materials. Bovine pericardium membrane is reported to have been used for a variety of surgical procedures, producing favorable outcomes. The success of these surgical procedure puts forth bovine pericardium membrane one of the most suitable choices for barrier material in guided tissue regeneration procedures. Results: The paper will review the numerous applications of bovine pericardium grafts in the fields of general and dental surgery. These studies provide substantial evidence for establishing, bovine pericardium membrane as a highly versatile graft material. Conclusion: The paper concludes with possible ways the material can be engineered to achieve an even better outcome. [ABSTRACT FROM AUTHOR]
- Published
- 2014
48. An In Vitro Genotoxicity Study of Biphasic Calcium Phosphate on Ames Test.
- Author
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Kaur Chahil, Yashvin, Wai Chong Ren, Hassan, Akram, Masudi, Sam'am Malik, and Khursheed Alam, Mohammad
- Abstract
Background: Biphasic Calcium Phosphate (BCP) is being engineered as a bone substitute material that can be widely used in maxillofacial, dentistry and orthopaedic applications. The objective of this in vitro study was to evaluate the genotoxicity of BCP using Bacterial Reverse Mutation Assay (Ames Test). Methods: This was a descriptive experimental study performed on Salmonella typhimurium TA1538 strain using pre-incubation method in the presence and absence of an exogenous metabolic activation system. The bacteria were incubated for 48 hours at 37 ± 0.5°C before the colony growth or revertant colonies were counted. Data obtained were analyzed by using non-statistical method. Results: The investigation of the genotoxic reaction on the test material revealed that the numbers of revertant colonies in strain with and without S9 mix were less than twice of the negative control for all tested concentration. Conclusion: The results of the tests showed that BCP was considered to be non-mutagenic under the present test condition. [ABSTRACT FROM AUTHOR]
- Published
- 2014
49. The Assessment of Proliferation Rate of Dental Pulp Stem Cells and Stem Cell from Human Exfoliated Deciduous Teeth by Using Two Different Scaffold.
- Author
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Nawi, Nurul Saadah Binti Mat, Ariffín, Zaihan, Alam, Mohammad Khursheed, Noor, Siti Noor Fazliah Mohd, and Hassan, Akram
- Abstract
Introduction: Dental pulp stem cells (DPSC) and stem cells from human exfoliated deciduous teeth (SHED) were identified to be highly proliferative and clonogenic cells. Objectives: The objective was to assess the proliferation rate of DPSC and SHED in presence of two different scaffolds, synthetic granular hjdroxj apetite bone graft (Granumas®) and coral scaffolds. Materials and Methods: All teeth were extracted and isolation of the stem cells from dental pulp was done following standard protocol. The stem cells were cultured with a Modified Eagle's Medium (GIBCO/BRL) supplemented with 10% fetal Bovine serum (Equitec-Bio, Kerrville, TX, 100 fan L- glutamine (Wako Pure Chemicals, Osaka), 100 unit/ml penicillin, and 100 mg/ml streptomycin (Biofluids, Rokville, MD). The cells proliferation rate of the DPSC and SHED with scaffolds (Granumas® and coral scaffolds) and without scaffolds was assessed using Alamar Blue (Biosource Internatioal, Inc, USA) and the absorbance of the media was measured spectrophotometrically using ELISA plate reader (Tecan, DKSH) at a wavelength of 570 nm and 600 nm at 0 minute, 60 minutes, 120 minutes, 180 minutes, 240 minutes at day 0, day 4 and day 7. Results and Conclusion: The proliferation rate of DPSC is higher compared to SHED. Cancellous coral scaffold is more suitable in promoting stem cells differentiation and proliferation compared to synthetic hydroxyapetite granular bone graft. [ABSTRACT FROM AUTHOR]
- Published
- 2013
50. Fluoride Release from Dental Restorations in De-Ionized Water and Artificial Saliva.
- Author
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Yusoff, Nik Noorul Azam bt Nik, Ariffin, Zaihan, Hassan, Akram, and Alam, Mohammad Khursheed
- Abstract
Objective: The aims of this study is to compare the fluoride release from Fuji Vll (conventional glass-ionomer), Fuji II LC (resin-modified glass-ionomer), Dyract (compomer) and Z350 (composite) in de-ionized water and artificial saliva and also to compare the accumulation fluoride release from the tested dental restorations in de-ionized water and artificial saliva. Materials and Method: This is in-vitro experimental laboratory study that studied on fluoride released from four different dental restoration materials Fuji Vll (conventional glass-ionomer), Fuji II LC (resin-modified glass-ionomer), Dyract (compomer) and Z350 (composite) in de-ionized water and artificial saliva. The amount of fluoride release was measured at the integral time from day 1, day 2, day 3, day 4 and day 5. 20 discs of each material were prepared according to manufacturers'instructions and were placed in the disc moulds (same dimensions). They then were divided into two groups. Fach group consisting of 10 discs of each material was stored in de-ionized water (Group I) and artificial saliva (Group II) for 5 days, at 37°C Collected media buffer was measured by ISE meter and total ionic strength adjustment buffer (TISAB) for every 24 hours. TISAB was used to decomplex contaminating ion and provide a constant background ionic strength. Data was analyzed using Kruskal-Wallis and Mann-Whitney test. Results: There was significant different amount of fluoride release from all the tested material both in de-ionized water and artificial saliva. Fuji Vll showed the greatest amount of fluoride release in both de-ionized water and artificial saliva followed by Fuji II LC, Dyract and Z350. There is significant association of fluoride ion release from dental restorations between in de-ionized water and artificial saliva except for Z350 (p = 0.787). There is greater amount of fluoride release by all tested material in de-ionized water compared with artificial saliva. Conclusion: The fluoride release is highest in resin-modified glass-ionomers, followed by conventional GICs, polyacid-modi- fied resin composite (compomer), and resin composite. There is greater amount of fluoride release by the tested material in de- ionized water compared with artificial saliva. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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