34 results on '"Fazal-ur-Rehman"'
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2. Effect of heteroatoms on structural, electronic and spectroscopic properties of polyfuran, polythiophene and polypyrrole: A hybrid DFT approach
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Hassan, Asma, Ismail, Muhammad, Reshak, Ali H., Zada, Zeshan, Khan, Abdul Ahad, M, Fazal Ur Rehman, Arif, Muhammad, Siraj, Khadija, Zada, Shafqat, Murtaza, G., and Ramli, Muhammad M.
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- 2023
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3. Insight into the electronic structure, magnetic, and thermoelectric properties of transition metal pnictides KCr2L2 (K= Ca, Sr; L = P, As): As substitute source for renewing energy
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Zada, Zeshan, Khan, Abdul Ahad, Reshak, Ali H., khan, Irfan, Zada, Shafqat, Ismail, Muhammad, Fazal-ur-Rehman, Muhammad, Saqib, Muhammad, Murtaza, G., Khan, Qaisar, and Ramli, Muhammad M.
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- 2023
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4. Coloring efficacy of Nyctanthes Arbortristis based yellow natural dye for surface-modified wool
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Adeel, Shahid, Ahmad, Sehrish, Habib, Noman, Fazal-ur-Rehman, Mia, Rony, and Ahmed, Bulbul
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- 2022
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5. Investigating In Situ Expression of Neurotrophic Factors and Partner Proteins in Irreversible Pulpitis.
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Israr, Fatima, Masood ul Hasan, Syed, Hussain, Mushtaq, Qazi, Fazal ur Rehman, and Hasan, Arshad
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NEUROTROPHINS ,BRAIN-derived neurotrophic factor ,NERVE growth factor ,PULPITIS - Abstract
In situ assessments of neurotrophic factors and their associated molecular partners have not been explored to date, particularly in humans. The present investigation aimed to explore the expressional dysregulation of neurotrophic factors (nerve growth factor [NGF], brain derived neurotrophic factor [BDNF], and NT4/5), their receptors (TrkA and TrkB), and their modulators (USP36 and Nedd4-2) directly in irreversibly inflamed human pulp tissues. Forty samples each of healthy and irreversibly inflamed pulp were extirpated for the study. Immunohistochemical examinations were carried out for the anatomic changes and expression of neurotrophic factors and partner proteins. Expression was digitally quantified using the IHC profiler module of ImageJ and deduced as optical density. Statistical analyses were carried out by GraphPad Prism. Decrease in nuclear and vessel diameters was observed in irreversibly inflamed pulp tissues. NGF and BDNF were found to be significantly upregulated in symptomatic irreversible pulpitis (SIP), whereas no significant difference was observed in the expression of TrkA and TrkB. Expression of Nedd4-2, USP36, and TrkA was found positively correlated with the NGF in healthy pulp tissues. However, in SIP, positive correlation was only observed between the expression of USP36 and NGF. Among the ligands, BDNF expression was found positively correlated with NGF in healthy pulp but not with NT4/5. In the case of SIP, no correlation was observed between any neurotrophic factors. Upregulation of NGF, BDNF, USP36 and Nedd4-2 in SIP indicates dysregulation in the molecular events underlying the disease biology and could be exploited as potential markers for the disease diagnosis. [ABSTRACT FROM AUTHOR]
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- 2023
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6. Surface modified ZnO nano structures: Electrochemical studies for energy applications and removal of emerging organic pollutant dye by photo induced hetero-catalysis
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Fazal Ur Rehman, M., Zahra, Manzar, Shoukat, Waseem, Reshak, Ali H., Ali, Dania, Raza, Aoun, Arshad, Sabeen, and Ramli, Muhammad M.
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- 2023
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7. Fast and thermal neutron intensity measurements at the KFUPM PGNAA setup
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Al-Jarallah, M.I, Naqvi, A.A, Fazal-ur-Rehman, and Abu-jarad, F
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- 2002
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8. Environmental friendly bio-dyeing of silk using Alkanna tinctoria based Alkannin natural dye.
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Fazal-ur-Rehman, Adeel, Shahid, Liaqat, Salman, Hussaan, Muhammad, Mia, Rony, Ahmed, Bulbul, and Wafa, Haddar
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NATURAL dyes & dyeing , *SILK , *TEXTILE industry , *MORDANTS , *DYES & dyeing - Abstract
Application of bio-dyes, especially plant-based, is becoming increasingly popular in many industries such as textiles, food and pharmaceuticals. This trend could be explained by the ecological and durable nature of these compounds. The current paper aimed to investigate the microwave-assisted isolation of Alkannin dye from Alkanna tinctoria followed by the dyeing of bio-mordanted silk. For the purpose, acid solubilized, water solubilized, and acid-methanol solubilized extracts were obtained. Both respective extracts and silk fabrics were microwave irradiated for 2, 4 and 6 min. To ensure a green and clean dyeing process, bio-mordants were used. It is observed that acid solubilized extract applied at 55 °C for 55 min having 7 g/100 mL of NaCl salt as the exhausting agent has given extraordinary higher color strength (K/S) onto Microwave treatment (MW) treated silk fabric. Colorfastness tests using ISO-recommended requirements found that bio-mordants outperformed chemical mordants in terms of color depth and fastness. According to this study, it was proven that MW improved the dyeing performance of Alkannin in an acid-solubilized medium, where as in addition to the application of bio-mordants in comparison with sustainable chemical mordants have improved color characteristics of silk fabric dyed with Alkanna tinctoria extract. [Display omitted] • The microwave-assisted extraction of Alkannin dye was investigated. • Bio-mordanting were used as a replace of metal mordant. • Bio-dyeing of silk shown excellent fastness properties. • Alkanna tinctoria based Alkannin dye can be an alternative of synthetic dyes. [ABSTRACT FROM AUTHOR]
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- 2022
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9. Sample to moderator volume ratio effects in neutron yield from a PGNAA setup
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Naqvi, A.A., Fazal-ur-Rehman, Nagadi, M.M., and Khateeb-ur-Rehman
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NEUTRONS , *NUCLEAR reactors , *GAMMA rays , *IONIZING radiation - Abstract
Abstract: Performance of a prompt gamma ray neutron activation analysis (PGNAA) setup depends upon thermal neutron yield at the PGNAA sample location. For a moderator, which encloses a sample, thermal neutron intensity depends upon the effective moderator volume excluding the void volume due to sample volume. A rectangular moderator assembly has been designed for the King Fahd University of Petroleum and Minerals (KFUPM) PGNAA setup. The thermal and fast neutron yield has been measured inside the sample cavity as a function of its front moderator thickness using alpha particle tracks density and recoil proton track density inside the CR-39 nuclear track detectors (NTDs). The thermal/fast neutron yield ratio, obtained from the alpha particle tracks density to proton tracks density ratio in the NTDs, shows an inverse correlation with sample to moderator volume ratio. Comparison of the present results with the previously published results of smaller moderators of the KFUPM PGNAA setup confirms the observation. [Copyright &y& Elsevier]
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- 2007
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10. Discontinuous steering control for nonholonomic systems with drift
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Fazal-ur-Rehman
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MECHANICS (Physics) , *ROTATIONAL motion (Rigid dynamics) , *TORQUE , *VECTOR analysis - Abstract
Abstract: This paper presents a simple method for the construction of steering control law for nonholonomic systems with drift and its effectiveness is tested on three different nonholonomic control systems such as a system with six state variables and three inputs, knife-edge example, and a rigid body with two torque actuators. This method does not necessitate conversion of the system models into “chained form” and does not rely on any special transformation techniques. The feedback controls are piecewise constant, states dependent and the method is based on the construction of a cost function V which is the sum of two semi-positive definite functions and , where is the function of the first state variables which can be steered along the given vector fields and is the function of the remaining – state variables which can be steered along the missing Lie brackets. The values of the functions and allow in determining a desired direction of system motion and permit to construct a sequence of controls such that the sum of these functions decreases in an average sense. [Copyright &y& Elsevier]
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- 2005
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11. Correlation between radon exhalation and radium content in granite samples used as construction material in Saudi Arabia
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Al-Jarallah, M.I., Fazal-ur-Rehman, Musazay, M.S., and Aksoy, A.
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RADON , *CONSTRUCTION materials , *GRANITE , *RADIUM - Abstract
Abstract: Measurements of radon exhalation for a total of 205 selected samples of construction materials used in Saudi Arabia were carried out using an active radon gas analyzer with an emanation container. It was found that granite samples were the main source of radon exhalation. The radon exhalation rates per unit area from these granite samples varied from below the minimum detection limit up to with an average of 1.5 . The radium contents of 27 granite samples were measured using an HPGe-based spectroscopy setup. The 226Ra content of the granites varied from below the minimum detection limit up to , with an average of . The linear correlation coefficient between exhaled radon and radium content was found to be 0.90. [Copyright &y& Elsevier]
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- 2005
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12. Assessment of fast and thermal neutron ambient dose equivalents around the KFUPM neutron source storage area using nuclear track detectors
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Fazal-ur-Rehman, Al-Jarallah, M.I., Abu-Jarad, F., and Qureshi, M.A.
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THERMAL neutrons , *NUCLEAR track detectors , *UNIVERSITIES & colleges , *DOSIMETERS , *NUCLEAR research - Abstract
Abstract: A set of five 241Am–Be neutron sources are utilized in research and teaching at King Fahd University of Petroleum and Minerals (KFUPM). Three of these sources have an activity of 16Ci each and the other two are of 5Ci each. A well-shielded storage area was designed for these sources. The aim of the study is to check the effectiveness of shielding of the KFUPM neutron source storage area. Poly allyl diglycol carbonate (PADC) Nuclear track detectors (NTDs) based fast and thermal neutron area passive dosimeters have been utilized side by side for 33 days to assess accumulated low ambient dose equivalents of fast and thermal neutrons at 30 different locations around the source storage area and adjacent rooms. Fast neutron measurements have been carried out using bare NTDs, which register fast neutrons through recoils of protons, in the detector material. NTDs were mounted with lithium tetra borate (Li2B4O7) converters on their surfaces for thermal neutron detection via and nuclear reactions. The calibration factors of NTD both for fast and thermal neutron area passive dosimeters were determined using thermoluminescent dosimeters (TLD) with and without a polyethylene moderator. The calibration factors for fast and thermal neutron area passive dosimeters were found to be 1.33 proton tracks and 31.5 alpha tracks , respectively. The results show variations of accumulated dose with the locations around the storage area. The fast neutron dose equivalents rates varied from as low as up to whereas those for thermal neutron ranged from as low as up to . The study indicates that the area passive neutron dosimeter was able to detect dose rates as low as 7 and from accumulated dose for thermal and fast neutrons, respectively, which were not possible to detect with the available active neutron dosimeters. [Copyright &y& Elsevier]
- Published
- 2005
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13. Steering control of nonholonomic systems with drift: The extended nonholonomic double integrator example
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Fazal-ur-Rehman
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DIFFERENTIAL equations , *LYAPUNOV functions , *VECTOR analysis , *LINEAR algebra - Abstract
Abstract: This paper presents two different kinds of steering control strategies for a system of extended nonholonomic double integrator, which is an example of nonholonomic control systems with drift. The first strategy presents piece-wise constant, states-dependent feedback control law. The method is based on the construction of a cost function V (not a Lyapunov function), which is the sum of two semi-positive definite functions and . The semi-positive definite function is dependent on first m state variables which can be steered along the given vector fields and is dependent on the remaining state variables which can be steered along the missing Lie brackets. The values of the functions and allow determination of a desired direction of system motion and permit to construct a sequence of controls such that the sum of these functions decreases in an average sense. The second strategy presents a time-varying feedback law based on the model reference approach, where the trajectory of the extended system is chosen as the model reference trajectory. The controllers are designed in such a way that after each time period T, the trajectory of the nonholonomic double integrator intersects the trajectory of the model reference, which can be made asymptotically stable. The proposed feedback law is as a composition of a standard stabilizing feedback control for a Lie bracket extension of the original system and a periodic continuation of a specific solution to an open loop control problem stated for an abstract equation on a Lie group. This approach does not rely on a specific choice of a Lyapunov function, and does not require transformations of the model to chained forms. [Copyright &y& Elsevier]
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- 2005
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14. Verification of design calculations of a PGNAA setup using nuclear track detectors.
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A.A. Naqvi, Fazal-ur-Rehman, M.M. Nagadi, M. Maslehuddin, Khateeb-ur-Rehman, and S. Kidwai
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NUCLEAR counters , *ENGINEERING instruments , *PHYSICS instruments , *DETECTORS - Abstract
A rectangular moderator assembly has been designed for the PGNAA setup at King Fahd University of Petroleum and Minerals (KFUPM). The design calculations of the rectangular moderator, which were obtained through Monte Carlo simulation, have been verified experimentally through thermal neutron yield measurement using CR-39 nuclear track detectors (NTDs). These measurements were carried out at the KFUPM 350 keV accelerator using 2.8 MeV pulsed neutron beam from D (d,n) reaction. The thermal neutron yield was measured inside the sample volume of the rectangular moderator by two NTDs fixed at back and front end of the sample cavity. The good agreement between the experimental results and the results of the calculations shows useful application of NTDs in verification of design calculations of a PGNAA setup. [ABSTRACT FROM AUTHOR]
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- 2004
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15. Application of the can technique and radon gas analyzer for radon exhalation measurements
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Fazal-ur-Rehman, Al-Jarallah, M.I., Musazay, M.S., and Abu-Jarad, F.
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RADON , *CERAMICS , *GRANITE , *URANIUM - Abstract
A passive “can technique” and an active radon gas analyzer with an emanation container were applied for radon exhalation rate measurements from different construction materials, viz. five marble seven ceramic and 100 granite tiles used in Saudi Arabia. The marble and ceramic tiles did not show detectable radon exhalation using the active radon gas analyzer system. However the granite tiles showed relatively high radon exhalations, indicating a relatively high uranium content. A comparison of the radon exhalation rates measured by the two techniques showed a linear correlation coefficient of 0.57. The radon exhalation rates from the granites varied from 0.02 to 6.58 Bq m−2 h−1 with an average of 1.35±1.40 Bq m−2 h−1. The geometric mean and the geometric standard deviation of the frequency distribution were found to be 0.80 and 3.1, respectively. The track density found on the nuclear track detectors in the can technique exposed to the granites, having high exhalation rates, varied linearly with exposure time with a linear correlation coefficient of 0.99. This experimental finding agrees with the theoretical prediction. The can technique showed sensitivity to low radon exhalation rates from ceramic, marble and some granite over a period of 2 months, which were not detectable by the active radon gas analyzer system. The reproducibility of data with both measuring techniques was found to be within a 7% deviation. [Copyright &y& Elsevier]
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- 2003
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16. Detection of 210Po on filter papers 16 years after use for the collection of short-lived radon progeny in a room
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Abu-Jarad, F. and Fazal-ur-Rehman
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POTENTIAL energy surfaces , *RADON - Abstract
Radon gas was allowed to accumulate in its radium source and then injected into a 36 m3 test room, resulting in an initial radon concentration of 15 kBq m–3. Filter papers were used to collect the short-lived radon progeny and thus to measure the Potential Alpha Energy Concentration (PAEC) in-situ in the year 1984 at different times and conditions according to the experimental design. The radon progeny collected on the filter papers were studied as a function of aerosol particle concentration ranging from 102–105 particles cm–3 in three different experiments. The highest aerosol particle concentration was generated by indoor cigarette smoking. Those filters were stored after the experiment, and were used after 16 years to study the activity of the radon long-lived alpha emitter progeny, 210Po (T1/2=138 days). This isotope is separated from the short-lived progeny by 210Pb beta emitter with 22.3 years half-life. After 16 years’ storage of these filters, each filter paper was sandwiched and wrapped between two CR-39 nuclear track detectors, to put the detectors in contact with the surfaces of different filters, for 337 days. Correlation between the PAEC measured using filter papers in the year 1984 and the activity of long-lived alpha emitter 210Po on the same filter papers measured in the year 2000 were studied. The results of the 210Po activity showed a very good correlation of 0.92 with the PAEC 16 years ago. The results also depict that the PAEC and 210Po activity in indoor air increased with the increase of aerosol particle concentration, which shows the attachment of short-lived radon progeny with the aerosol particles. The experiment proves that indoor cigarette smoking is a major source of aerosol particles carrying radon progeny and, thus, indoor cigarette smoking is an additional source of internal radiation hazard to the occupants whether smoker or non-smoker. [Copyright &y& Elsevier]
- Published
- 2003
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17. Performance tests of external moderators of a PGNAA setup
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Naqvi, A.A., Fazal-ur-Rehman, Al-Jarallah, M.I., Abu-Jarad, F., and Maslehuddin, M.
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NUCLEAR activation analysis , *GAMMA rays , *THERMAL neutrons - Abstract
Performance tests of external cylindrical moderators of an accelerator-based prompt gamma ray neutron activation analysis (PGNAA) setup have been carried out through thermal neutrons and prompt γ-ray yield measurements. The PGNAA setup is to be used for analysis of cement samples. This study was conducted to investigate the effects of geometry of cylindrical moderator on yield of thermal neutrons and prompt γ-rays for two different types of moderator assemblies. One of the moderators was to be used with a small sample and the other to be used with a large sample. Fast and thermal neutron yield was measured inside the sample volume as a function of the front moderator thickness as well as sample length. Neutron yield measurement was carried out at the King Fahd University of Petroleum and Minerals 350 keV pulsed beam accelerator using nuclear track detectors. The pulsed 200 keV deuteron beam with 5 ns pulse width and 31.25 kHz frequency was used to produce 2.8 MeV neutrons via D(d,n) reaction. Neutron yield measurements showed that the large sample moderator has a smaller yield of thermal neutrons as compared to the small sample moderator, which is in complete agreement with the results of Monte Carlo yield calculations of the thermal and fast neutrons from both the moderators.Finally, the prompt γ-ray yield from a Portland cement sample was measured using the two moderators and was compared with each other. As predicted by Monte Carlo simulations, in spite of a smaller yield of thermal neutrons, the large sample moderator has a higher yield of prompt γ-rays. [Copyright &y& Elsevier]
- Published
- 2003
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18. Indoor radon measurements in dwellings of four Saudi Arabian cities
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Al-Jarallah, M.I., Fazal-ur-Rehman, Abu-Jarad, F., and Al-Shukri, A.
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RADON , *DWELLINGS - Abstract
An indoor radon survey of a total of 269 dwellings, with one dosimeter per house, distributed in four Saudi Arabian cities was carried out. The objective of this survey was to carry out indoor radon measurements of two cities in the Eastern Province, Khafji and Hafr Al-Batin and to compare this with two cities in the Western Province, Al-Madina and Taif. The survey provides additional information about indoor radon concentrations in Saudi Arabia. The results of the survey in these cities showed that the overall minimum, maximum and average radon concentration were
7,137 and30 Bq m−3 , respectively. The lowest average radon concentration(20 Bq m−3) was found in Hafr Al-Batin, while the highest average concentration was found in Khafji(40 Bq m−3) . [Copyright &y& Elsevier]- Published
- 2003
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19. The effects of high fat diet, bone healing, and BMP-2 treatment on endothelial cell growth and function.
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Bhatti, Fazal Ur Rehman, Dadwal, Ushashi C., Valuch, Conner R., Tewari, Nikhil P., Awosanya, Olatundun D., de Andrade Staut, Caio, Sun, Seungyup, Mendenhall, Stephen K., Perugini III, Anthony J., Nagaraj, Rohit U., Battina, Hanisha L., Nazzal, Murad K., Blosser, Rachel J., Maupin, Kevin A., Childress, Paul J., Li, Jiliang, and Kacena, Melissa A.
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HIGH-fat diet , *CELL physiology , *LOW-fat diet , *ENDOTHELIAL cells , *CELL growth - Abstract
Angiogenesis is a vital process during the regeneration of bone tissue. The aim of this study was to investigate angiogenesis at the fracture site as well as at distal locations from obesity-induced type 2 diabetic mice that were treated with bone morphogenetic protein-2 (BMP-2, local administration at the time of surgery) to heal a femoral critical sized defect (CSD) or saline as a control. Mice were fed a high fat diet (HFD) to induce a type 2 diabetic-like phenotype while low fat diet (LFD) animals served as controls. Endothelial cells (ECs) were isolated from the lungs (LECs) and bone marrow (BMECs) 3 weeks post-surgery, and the fractured femurs were also examined. Our studies demonstrate that local administration of BMP-2 at the fracture site in a CSD model results in complete bone healing within 3 weeks for all HFD mice and 66.7% of LFD mice, whereas those treated with saline remain unhealed. At the fracture site, vessel parameters and adipocyte numbers were significantly increased in BMP-2 treated femurs, irrespective of diet. At distal sites, LEC and BMEC proliferation was not altered by diet or BMP-2 treatment. HFD increased the tube formation ability of both LECs and BMECs. Interestingly, BMP-2 treatment at the time of surgery reduced tube formation in LECs and humeri BMECs. However, migration of BMECs from HFD mice treated with BMP-2 was increased compared to BMECs from HFD mice treated with saline. BMP-2 treatment significantly increased the expression of CD31, FLT-1, and ANGPT2 in LECs and BMECs in LFD mice, but reduced the expression of these same genes in HFD mice. To date, this is the first study that depicts the systemic influence of fracture surgery and local BMP-2 treatment on the proliferation and angiogenic potential of ECs derived from the bone marrow and lungs. • Mice fed HFD for 12 weeks acquired a T2D-like metabolic phenotype. • BMP-2 treatment enhanced fracture healing in HFD mice 3 weeks post-surgery. • BMP-2 promotes vessel and adipocyte formation in the fracture callus. • ECs isolated from lungs and bone marrow of HFD mice have enhanced tube formation. • BMP-2 treatment in vivo 3 weeks prior to EC isolation inhibits tube formation in vitro. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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20. Photoneutron intensity variation with field size around radiotherapy linear accelerator 18-MeV X-ray beam
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Al-Ghamdi, H., Fazal-ur-Rehman, Al-Jarallah, M.I., and Maalej, N.
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NEUTRONS , *DOSIMETERS , *RADIATION therapy equipment , *NUCLEAR track detectors , *MEDICAL electronics , *RADIATION measurements , *X-rays - Abstract
Abstract: In X-ray radiotherapy accelerators, neutrons are produced mainly by reaction when high energy X-rays interact with high Z materials of the linear accelerator head. These materials include the lead (Pb) used as shielding in the collimator, tungsten target used for the production of X-rays and iron (Fe) in the accelerator head. These unwanted neutrons contaminate the therapeutic beam and contribute to the patient dose during the treatment of a cancer patient. Knowing the neutron distribution around the radiotherapy accelerator is therefore desired. CR-39 nuclear track detectors (NTDs) were used to study the variation of fast and thermal neutron relative intensities around an 18MeV linear accelerator X-ray beam with the field sizes of 0, , , and . For fast neutron detection, bare NTDs were used. For thermal neutron detection, NTDs were covered with lithium tetra borate converters. The NTDs were placed at different locations in the direction perpendicular to the treatment couch (transversal) and in the direction parallel to the treatment couch (longitudinal) with respect to the isocenter of the accelerator. The fast neutron relative intensity is symmetrical about the beam axis and exhibits an exponential-like drop with distance from the isocenter of the accelerator for all the field sizes. At the primary beam (isocenter), the relative fast neutron intensity is highest for field size and decreases linearly with the decrease in the field size. However, fast neutron intensities do not change significantly with beam size for the measurements outside the primary beam. The fast neutron intensity in the longitudinal direction outside the primary beam decreases linearly with the field size. The thermal neutron intensity, at any location, was found to be almost independent of the field size. [Copyright &y& Elsevier]
- Published
- 2008
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21. Comparative study of short- and long-term indoor radon measurements
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Al-Jarallah, M.I., Fazal-ur-Rehman, and Abdalla, Khalid
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RADON , *RADIATION measurements , *COMPARATIVE studies , *DOSIMETERS , *NOBLE gases - Abstract
Abstract: Short-term indoor radon measurements are used widely. Therefore, it is interesting to find out a correlation between these measurements and long-term measurements which reflect a better average radon concentration of individual measurement. To find the correlation between the two measurements of indoor radon concentrations at low radon levels, a study was carried out at 34 locations of King Fahd University of Petroleum & Minerals (KFUPM), Dhahran, Saudi Arabia using active and passive methods. In the short-term active method, a radon gas analyzer (AlphaGUARD) was used for a duration of 24h in each measurement. In the long-term passive method, CR-39 based radon dosimeters were utilized for a period of 6 months, from January 2006 to June 2006. The short-term active measurements showed that the average, minimum and maximum radon concentrations were 19, 8 and , respectively, with a standard deviation of . The long-term passive measurements showed that the average, minimum and maximum radon concentrations were 25, 10 and , respectively, with a standard deviation of . The two measurements showed a poor correlation . The long-term measurements showed on the average higher concentrations by a factor of 1.3. [Copyright &y& Elsevier]
- Published
- 2008
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22. Determination of equilibrium factor between radon and its progeny using surface barrier detector for various shapes of passive radon dosimeters
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Jamil, Khalid, Fazal-ur-Rehman, Ali, Safdar, and Khan, H.A
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- 1997
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23. Effect of mercerization and gamma irradiation on the dyeing behaviour of cotton using stilbene based direct dye
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Bhatti, Ijaz Ahmad, Adeel, Shahid, Fazal-ur-Rehman, Irshad, Misbah, and Abbas, Muhammad
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MERCERIZATION , *GAMMA rays , *STILBENE , *COTTON textiles , *PARAMETER estimation , *HYDROGEN-ion concentration - Abstract
Abstract: The dyeing behaviour of mercerized and gamma irradiated cotton fabric using stilbene based direct dye has been investigated. The fabric was treated with different concentrations of alkali to optimize the mercerization. The optimum mercerized cotton fabric was irradiated to absorbed doses of 2, 4, 6, 8 and 10kGy using Cs-137 gamma irradiator. Dyeing was performed using irradiated and un-irradiated cotton with dye solutions. The dyeing parameters such as temperature, time of dyeing, pH of dyeing solutions and salt concentration were optimized. The colour strength values of dyed fabrics were evaluated by comparing irradiated and un-irradiated cotton in CIE Lab system using Spectra flash SF650. Methods suggested by International Standard Organization (ISO) were employed to study the effect of gamma irradiation on the colourfastness properties of dyed fabric. It was found that mercerized and irradiated cotton have not only improved the colour strength but enhanced the rating of fastness properties also. [Copyright &y& Elsevier]
- Published
- 2012
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24. Radon concentration measurements in the desert caves of Saudi Arabia
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Al-Mustafa, Hanan, Al-Jarallah, M.I., Fazal-ur-Rehman, and Abu-Jarad, F.
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RADON , *DESERTS , *CAVES , *DOSIMETERS - Abstract
Abstract: Beneath the harsh deserts of Saudi Arabia lie dark chambers and complex mazes filled with strange shapes and wondrous beauty. Radon concentration measurements have been carried out in the desert caves of Al-Somman Plateau in the Eastern Province of Saudi Arabia. Passive radon dosimeters, based on alpha particle etch track detectors with an inlet filter, were used in this study. A total of 59 dosimeters were placed in five caves for a period of six months. Out of 59 dosimeters, 37 could be collected for analysis. Measurements showed significant variations in radon concentrations in caves depending upon their natural ventilation. The results of the study show that the average radon concentration in the different caves ranges from 74 up to 451Bqm. The average radon concentration in four of the caves was low in the range 74–114Bqm. However, one cave showed an average radon concentration of 451Bqm. Radon is not a problem for tourists in the majority of caves. However, sometimes it may imply some limitation to the working time of guides. [Copyright &y& Elsevier]
- Published
- 2005
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25. Neutron moderation in a bulk sample and its effects on PGNAA setup geometry
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Al-Jarallah, M.I., Naqvi, A.A., Fazal-ur-Rehman, Maselehuddin, M., Abu-Jarad, F., and Raashid, M.
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THERMAL neutrons , *GAMMA rays , *NUCLEAR track detectors , *PARTICLE tracks (Nuclear physics) - Abstract
In a prompt gamma ray neutron activation analysis (PGNAA) setup, the neutron moderation in the bulk sample also plays a key role. This can even dominate the thermalization effects of the external moderator in some cases. In order to study the neutron moderation effect in the bulk sample, moderators with two different sizes of the sample were tested at the King Fahd University of Petroleum & Minerals (KFUPM) PGNAA facility. In these tests, the thermal neutron relative intensity and prompt gamma ray yield from the two moderators were measured using nuclear track detectors (NTDs) and NaI detector, respectively. As predicted by Monte Carlo simulations, the measured intensity of thermal neutron inside the large sample cavity due to the external moderator was smaller than that from the smaller sample cavity. Due to its larger size, additional thermalization of neutrons will take place in the larger sample. In spite of smaller thermal neutron yield from the external moderator at the large sample location, higher yield of the prompt gamma ray was observed as compared to that from the smaller sample. This confirms the significance of neutron moderation effects in the bulk sample and can thereby affect the PGNAA geometry size. This allows larger samples in conjunction with smaller moderators in the PGNAA setup. [Copyright &y& Elsevier]
- Published
- 2003
- Full Text
- View/download PDF
26. Indoor radon measurements in the Women College, Dammam, Saudi Arabia
- Author
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Al-Qahtani, Mona, Al-Jarallah, M.I., and Fazal-ur-Rehman
- Subjects
- *
RADON , *DOSIMETERS , *PARTICLE track etching , *NUCLEAR track detectors - Abstract
Abstract: Passive radon dosimeters, based on alpha particle etched track detectors, were used in the indoor radon survey of the College of Science for Girls in Dammam, Saudi Arabia. A total of 95 dosimeters were distributed in the academic departments and the administrative building in the College. The exposure time in all the buildings was one complete lunar year in the period October 2001–October 2002 to get the average annual indoor radon concentration. All the buildings were constructed with ready-made concrete, except the administrative building which constructed with ordinary concrete bricks. A significant difference in the average indoor radon concentrations in the two types of buildings was found. The average indoor radon concentration in the ready-made concrete buildings was whereas that for the ordinary concrete brick building was . This could be due to the fact that ready-made concrete has a significantly less voids for the radon to emanate compared with ordinary concrete bricks. The indoor radon concentration in the ground floor is slightly higher than that in the first and second floors. [Copyright &y& Elsevier]
- Published
- 2005
- Full Text
- View/download PDF
27. Indoor radon survey in dwellings of some regions in Yemen
- Author
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Khayrat, A.H., Al-Jarallah, M.I., Fazal-ur-Rehman, X., and Abu-Jarad, F.
- Subjects
- *
RADON , *SURVEYS , *DWELLINGS - Abstract
Indoor radon survey in a total of 241 dwellings, distributed in some regions of Yemen was performed, using CR-39 based radon monitors. The objective of this radon survey is to get representative indoor radon data of three regions, namely Dhamar, Taiz and Hodeidah, situated at different altitudes above sea level. The radon concentrations varied from 3 to
270 Bq m−3 with an average of42 Bq m−3 . It was found that the average radon concentration in the surveyed areas increases with altitudes. The highest average radon concentration of59 Bq m−3 was found in Dhamar city while the lowest average concentration of8 Bq m−3 was found in Hodeidah city. [Copyright &y& Elsevier]- Published
- 2003
- Full Text
- View/download PDF
28. Appraisal of marigold flower based lutein as natural colourant for textile dyeing under the influence of gamma radiations.
- Author
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Adeel, Shahid, Gulzar, Tahsin, Azeem, Muhammad, Fazal-ur-Rehman, null, Saeed, Muhammad, Hanif, Iram, and Iqbal, Naeem
- Subjects
- *
TEXTILE dyeing , *COLORFASTNESS (Textiles) , *MARIGOLDS , *LUTEIN , *GAMMA rays , *EXTRACTION (Chemistry) - Abstract
Maintaining colour strength and fastness of the fabrics dyed with natural colourants had been the major constraint of utilizing plant based dyes in modern textile practices. The present study was concerned with the extraction of lutein dye from marigold ( Tagetes erecta L.) flowers and role of gamma radiation in improving colour strength and fastness characteristics of the extracted dye. The investigation of dyed fabric in spectraflash showed that gamma ray treatment of 30 kGy was the optimum absorbed dose for surface modification to improve its dye uptake ability. Good colour strength was obtained when irradiated cotton (RC, 30 kGy) was dyed with extract of radiated marigold flower powder (RP) at 70 °C for 85 min, keeping M:L of 1:50 using dye bath of pH 5.0. The results from mordanting experiments revealed that 7% of tannic acid as pre-mordant and 5% of Cu as post-mordant were the best treatments to improve colour strength. It was found that gamma ray induced extraction of lutein from marigold flowers had a potential to be utilized as natural dyes in textile sector to produce yellowish green shades. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
29. Causal Assessment of Serum Urate Levels in Cardiometabolic Diseases Through a Mendelian Randomization Study.
- Author
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Keenan, Tanya, Zhao, Wei, Rasheed, Asif, Ho, Weang K., Malik, Rainer, Felix, Janine F., Young, Robin, Shah, Nabi, Samuel, Maria, Sheikh, Nasir, Mucksavage, Megan L., Shah, Omar, Li, Jin, Morley, Michael, Laser, Annika, Mallick, Nadeem Hayat, Zaman, Khan Shah, Ishaq, Mohammad, Rasheed, Syed Zahed, and Memon, Fazal-ur-Rehman
- Subjects
- *
URATES , *SERUM , *CORONARY disease , *GENETICS of type 2 diabetes , *SINGLE nucleotide polymorphisms , *EPIDEMIOLOGY , *GENETIC pleiotropy , *GENETICS - Abstract
Background: Although epidemiological studies have reported positive associations between circulating urate levels and cardiometabolic diseases, causality remains uncertain.Objectives: Through a Mendelian randomization approach, we assessed whether serum urate levels are causally relevant in type 2 diabetes mellitus (T2DM), coronary heart disease (CHD), ischemic stroke, and heart failure (HF).Methods: This study investigated 28 single nucleotide polymorphisms known to regulate serum urate levels in association with various vascular and nonvascular risk factors to assess pleiotropy. To limit genetic confounding, 14 single nucleotide polymorphisms exclusively associated with serum urate levels were used in a genetic risk score to assess associations with the following cardiometabolic diseases (cases/controls): T2DM (26,488/83,964), CHD (54,501/68,275), ischemic stroke (14,779/67,312), and HF (4,526/18,400). As a positive control, this study also investigated our genetic instrument in 3,151 gout cases and 68,350 controls.Results: Serum urate levels, increased by 1 SD due to the genetic score, were not associated with T2DM, CHD, ischemic stroke, or HF. These results were in contrast with previous prospective studies that did observe increased risks of these 4 cardiometabolic diseases for an equivalent increase in circulating urate levels. However, a 1 SD increase in serum urate levels due to the genetic score was associated with increased risk of gout (odds ratio: 5.84; 95% confidence interval: 4.56 to 7.49), which was directionally consistent with previous observations.Conclusions: Evidence from this study does not support a causal role of circulating serum urate levels in T2DM, CHD, ischemic stroke, or HF. Decreasing serum urate levels may not translate into risk reductions for cardiometabolic conditions. [ABSTRACT FROM AUTHOR]- Published
- 2016
- Full Text
- View/download PDF
30. Modification of cellulosic fibers to enhance their dyeability using UV-irradiation
- Author
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Bhatti, Ijaz Ahmad, Zia, Khalid Mahmood, Ali, Zobia, Zuber, Mohammad, and Fazal-ur-Rehman
- Subjects
- *
CELLULOSE fibers , *ULTRAVIOLET radiation , *DYES & dyeing , *MERCERIZATION , *SODIUM hydroxide , *HYDROGEN-ion concentration , *SCANNING electron microscopy - Abstract
Abstract: Present research was proposed to evaluate the effect of UV radiation on the dyeing of cellulosic fabrics with direct dyes. The cellulosic fabric was irradiated by using UV radiation assembly (180W) for different time intervals i.e., 30, 45, 60, 75 and 90min respectively. The alike set of fabrics was prepared varying the concentration of NaOH during mercerization of the fabrics. All the treated fabrics were dyed with direct dyes. The dyeing parameters such as temperature, time, pH and salt concentration were optimized. The standard methods were employed to evaluate the color strength at various levels of pH, temperature, dyeing contact time and salt concentration. Scanning electron microscope test was performed in order to evaluate the change in fibril structure and surface. The obtained results of the dyed fabrics previously treated with UV radiation and after mercerization were compared. The results revealed that the color strength of UV-irradiated fabric was high as compared to mercerized cellulosic fabrics. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
31. Modification of cellulosic fabric using polyvinyl alcohol, part-II: Colorfastness properties
- Author
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Zuber, Mohammad, Zia, Khalid Mahmood, Bhatti, Ijaz Ahmad, Jamil, Tahir, Fazal-ur-Rehman, and Rizwan, Ali
- Subjects
- *
CELLULOSE , *POLYVINYL alcohol , *COLORFASTNESS (Textiles) , *POLYESTER fibers , *FOURIER transform infrared spectroscopy , *CRYSTALLINE polymers - Abstract
Abstract: A series of aqueous solutions of poly(vinyl alcohol) of various commercial products were prepared and applied onto the surfaces of cotton and blends of cotton/polyester fabrics. Fourier transform infrared spectrophotometer was used to confirm the molecular structure of the polyvinyl alcohol used. Performance tests such as colorfastness to rubbing (dry and wet) and colorfastness to washing were determined. The controlling variables affecting the performance properties of the finished substrate such as post-treatment with poly(vinyl alcohol) of various commercial trades, concentration and dilutions were studied. Crocking, washing and hue change of the treated dyed and printed fabrics is accompanied by the formation of semi-inter-penetrated network structure due to the presence of the hydroxyl (–OH) groups which make feasible to a number of grafting and physical cross linking reactions of polymer backbone. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
32. Structural insights to investigate Conypododiol as a dual cholinesterase inhibitor from Asparagus adscendens
- Author
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Khan, Inamullah, Nisar, Muhammad, Khan, Nematullah, Saeed, Muhammad, Nadeem, Said, Fazal-ur-Rehman, Ali, Farooq, Karim, Nasiara, Kaleem, Waqar Ahmad, Qayum, Mughal, Ahmad, Hanif, and Khan, Ihsan Ali
- Subjects
- *
MEDICINAL plants , *MEDICAL botany , *CHOLINESTERASE inhibitors , *LIGANDS (Biochemistry) , *CYTOLOGICAL research , *ALTERNATIVE medicine , *ANALYSIS of variance , *ANIMAL experimentation , *BIOLOGICAL assay , *BIOLOGICAL models , *BIOPHYSICS , *DOSE-effect relationship in pharmacology , *DRUG toxicity , *RESEARCH methodology , *MOLECULAR biology , *PRIMATES , *PLANT extracts , *PILOT projects , *PHARMACODYNAMICS - Abstract
Abstract: The main aim of the current study was to explore molecular insights for potentially new dual cholinesterase inhibitor(s) from Asparagus adscendens via molecular docking. This medicinal plant is traditionally used as a nerve tonic and remedy for memory impairments. Conypododiol was isolated from the chloroform fraction of methanolic extract of A. adscendens, based on bioactivity guided isolation. Conypododiol exhibited significant inhibition of both acetylcholinesterase and butyrylcholinesterase, having the IC50 values 2.17±0.1μM and 11.21±0.1μM, respectively. IC50 values of the standard compound Galanthamine for both the enzymes were 0.537±0.018μM and 8.6±0.27μM, respectively. Based on MTT cytotoxicity assay, Conypododiol was found safe against LCMK-2 monkey kidney epithelial cells and mice hepatocytes. Molecular docking studies revealed the hydrogen bonding interactions of Conypododiol with His440 and Ser200 at esteratic site (ES), and also with Tyr334 at peripheral anionic site (PAS) of the aromatic gorge of acetylcholinesterase. Simultaneous contacts of Conypododiol with PAS and ES shows its significance as a bivalent ligand. This preliminary study highlighted the potential of Conypododiol to be further developed and modified as new lead compound identified by its folk use. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
33. Uniformity in radon exhalation from construction materials using can technique
- Author
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El-Amri, E.A., Al-Jarallah, M.I., Abu-Jarad, F., and Fazal-ur-Rehman
- Subjects
- *
RADON , *NUCLEAR track detectors , *CALIBRATION , *STATISTICAL correlation - Abstract
The uniformity in radon exhalation rates for 46 tiles of granite, marble and ceramic used as construction materials were determined using “Can Technique” employing CR-39 nuclear track detectors (NTDs). On each tile, two sealed cans, each enclosing one NTD fixed at the center of the tile surface area covered by the can, were mounted at two different locations of each individual tiles. The track production rates on the NTDs representing radon exhalation rates were measured. The radon exhalation rates from the surface of individual tiles showed uniform exhalations within the calculated uncertainties of the measured values. This makes Can Technique an alternative simple method to measure radon exhalation rates. Calibration required to convert track production rates into radon exhalation rates for the used can and NTD was done using an active technique. The correlation between the measurements by the two techniques shows a good linear correlation coefficient (0.83). [Copyright &y& Elsevier]
- Published
- 2003
- Full Text
- View/download PDF
34. Analgesic and anti-inflammatory activities of 11-O-galloylbergenin
- Author
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Arfan, Mohammad, Amin, Hazrat, Khan, Nematullah, Khan, Inamullah, Saeed, Muhammad, Khan, Muhammad Azim, and Fazal-ur-Rehman
- Subjects
- *
PAIN management , *MALLOTUS , *FISH oils , *TRADITIONAL medicine , *ETHNOPHARMACOLOGY , *PHARMACOLOGY , *THERAPEUTICS , *ALTERNATIVE medicine , *ANALGESICS , *ANALYSIS of variance , *ANIMAL experimentation , *ANTI-inflammatory agents , *BIOLOGICAL assay , *BIOLOGICAL models , *BIOPHYSICS , *RESEARCH methodology , *MEDICINAL plants , *MICE , *PRIMATES , *RATS , *STATISTICS , *PLANT stems , *T-test (Statistics) , *PLANT extracts , *DATA analysis , *PHARMACODYNAMICS - Abstract
Current study was designed to explore the analgesic and anti-inflammatory effects of a constituent isolated from Mallotus philippinensis, in order to validate its folk use. Materials and methods: 11-O-galloylbergenin was isolated from ethanolic extract of Mallotus philippinensis. Analgesic and anti-inflammatory activities of the test compound were assessed using formalin test and carrageenan-induced paw edema models. Results: 11-O-galloylbergenin showed significant analgesic activity at doses of 20 and 40mg/kg against formalin test in rats. Similarly, 11-O-galloylbergenin exhibited significant anti-inflammatory activity in carrageenan-induced paw edema model at doses of 10, 20 and 30mg/kg. Conclusion: 11-O-galloylbergenin has demonstrated its significant potential to be further investigated for its discovery as a new lead compound for management of pain and inflammation. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
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