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Advances in Nanoparticles, 2014
Fines migration is defined as separation of a Nano-sized particle by fluid flow in porous media a... more Fines migration is defined as separation of a Nano-sized particle by fluid flow in porous media and its migration along some distances and its entrapment in a narrow pore throat or its settlement on pore wall. Although this phenomenon happens in scales of Nano-meters, it can lead to sever irretrievable damages. This damage includes permeability reduction that causes drastic oil recovery reduction. There are several forces impacting a fine that is placed on a pore wall. Some of most important forces affecting settlement of a fine in porous media in presence of a fluid are electrical forces. Electrical forces consist of several long and short range forces. This study focuses on a long range force called Double Layer Force (DLF) that beside Van der Waals is one of most powerful electrical forces. DLF is a repulsive force that can repel a particle from pore wall and result separation of a Nano-sized solid which subsequently moves along with flowing fluid and clogs a throat. The DLF depends on the solid material (reservoir rock and fine) and fluid properties (i.e. ionic strength, pH). This study investigates how each of these parameters affects DLF and introduces proper conditions for reservoir water flooding for controlling fines migration.
International Ophthalmology
This study tests the hypothesis that subjects with proliferative diabetic retinopathy (PDR) have ... more This study tests the hypothesis that subjects with proliferative diabetic retinopathy (PDR) have a detectable rise in levels of serum vascular endothelial growth factor (VEGF), which is an important regulator of angiogenesis. Our investigation aims to evaluate plasma VEGF changes after pan-retinal photocoagulation (PRP) in diabetic patients. Twenty-nine type two diabetic patients (17 male, 12 female: mean age 53.13 ± 12.22 years) with PDR secondary to diabetes were studied. Blood samples were obtained before and at 2 months after the last PRP session. Serum VEGF levels were measured by ELISA. After PRP, the mean serum VEGF decreased, but this reduction was not remarkable (88.68 ± 71.09 vs. 77.01 ± 60.33 ng/ml) (P = 0.18). There was a statistically significant difference in serum VEGF changes between patients who had regressed PDR with patients who had progressed PDR (−25.98 ± 47.37 vs. 56.44 ± 31.7 ng/ml) (P = 0.003). Our results showed a significant reduction in levels of serum VEGF in the patients who had successful laser treatment. Our findings suggest that serum VEGF levels could be used for monitoring diabetic retinopathy outcome.
International Journal of Chemical Kinetics, 2005
Electrochemical oxidation of some catecholamines such as dopamine (1), L-dopa (2), and methyldopa... more Electrochemical oxidation of some catecholamines such as dopamine (1), L-dopa (2), and methyldopa (3) has been studied in various pH values, using cyclic voltammetry. The results indicate participation of catecholamines (1–3) in intramolecular cyclization reaction to form the corresponding o-quinone derivatives (1d–3d). In various pHs, based on ECE mechanism, the observed homogeneous rate constants (kobs) of cyclization reaction were estimated by comparing the experimental cyclic voltammetric responses with the digital-simulated results. Also, the cyclization rate constants (kcyc) were calculated using microscopic acidic dissociation constant of ammonium groups. The significant differences in electrochemical behavior, kobs and kcyc, of L-dopa (2) and methyldopa (3) with dopamine (1) are due to the effects of the side chain carboxyl group. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 37: 17–24, 2005
BMC Ophthalmology, 2004
The aim of this study was to identify risk factors for the development of retinopathy and microal... more The aim of this study was to identify risk factors for the development of retinopathy and microalbuminuria and their correlation in type II diabetic patients.
Anti-thyroid peroxidase antibody (anti-TPO) is a member of thyroid autoantibodies is important in... more Anti-thyroid peroxidase antibody (anti-TPO) is a member of thyroid autoantibodies is important in inducing and also diagnosing autoimmune thyroid diseases. Thyroid autoimmunity can cause several forms of thyroiditis and abnormal thyroid functions, ranging from hypothyroidism to hyperthyroidism. Evaluation of the relationship between serum levels of anti-TPO and thyroid hormones (T3, T4 and TSH) was aimed. In 2425 persons suspected of thyroid disease and referred to Yazd central medical laboratory by physicians during 2 years, the concentrations of serum anti-TPO and also serum T3, T4 and TSH were measured using ELISA and RIA methods, respectively. Most of the patients (53.53%) were between 20 to 39 years old. Females comprised 88.04% (2135 patients) and the remaining 290 patients (11.96%) were male. The differences between patients who had normal anti-TPO and those who had more than normal anti-TPO in different levels of T3, T4 and TSH were significant (p<0.0001). The correlation between TSH and T4 in patients who had abnormal anti-TPO were significant (r= 0.107, P=0.04, r=-0.160, p=0.002, respectively). Anti-TPO is a good marker for patients with autoimmune hypothyroidism who have high levels of TSH or less than normal T3 or T4 and there is a significant correlation between anti-TPO and both TSH and T4.
Advances in Nanoparticles, 2014
Fines migration is defined as separation of a Nano-sized particle by fluid flow in porous media a... more Fines migration is defined as separation of a Nano-sized particle by fluid flow in porous media and its migration along some distances and its entrapment in a narrow pore throat or its settlement on pore wall. Although this phenomenon happens in scales of Nano-meters, it can lead to sever irretrievable damages. This damage includes permeability reduction that causes drastic oil recovery reduction. There are several forces impacting a fine that is placed on a pore wall. Some of most important forces affecting settlement of a fine in porous media in presence of a fluid are electrical forces. Electrical forces consist of several long and short range forces. This study focuses on a long range force called Double Layer Force (DLF) that beside Van der Waals is one of most powerful electrical forces. DLF is a repulsive force that can repel a particle from pore wall and result separation of a Nano-sized solid which subsequently moves along with flowing fluid and clogs a throat. The DLF depends on the solid material (reservoir rock and fine) and fluid properties (i.e. ionic strength, pH). This study investigates how each of these parameters affects DLF and introduces proper conditions for reservoir water flooding for controlling fines migration.
International Ophthalmology
This study tests the hypothesis that subjects with proliferative diabetic retinopathy (PDR) have ... more This study tests the hypothesis that subjects with proliferative diabetic retinopathy (PDR) have a detectable rise in levels of serum vascular endothelial growth factor (VEGF), which is an important regulator of angiogenesis. Our investigation aims to evaluate plasma VEGF changes after pan-retinal photocoagulation (PRP) in diabetic patients. Twenty-nine type two diabetic patients (17 male, 12 female: mean age 53.13 ± 12.22 years) with PDR secondary to diabetes were studied. Blood samples were obtained before and at 2 months after the last PRP session. Serum VEGF levels were measured by ELISA. After PRP, the mean serum VEGF decreased, but this reduction was not remarkable (88.68 ± 71.09 vs. 77.01 ± 60.33 ng/ml) (P = 0.18). There was a statistically significant difference in serum VEGF changes between patients who had regressed PDR with patients who had progressed PDR (−25.98 ± 47.37 vs. 56.44 ± 31.7 ng/ml) (P = 0.003). Our results showed a significant reduction in levels of serum VEGF in the patients who had successful laser treatment. Our findings suggest that serum VEGF levels could be used for monitoring diabetic retinopathy outcome.
International Journal of Chemical Kinetics, 2005
Electrochemical oxidation of some catecholamines such as dopamine (1), L-dopa (2), and methyldopa... more Electrochemical oxidation of some catecholamines such as dopamine (1), L-dopa (2), and methyldopa (3) has been studied in various pH values, using cyclic voltammetry. The results indicate participation of catecholamines (1–3) in intramolecular cyclization reaction to form the corresponding o-quinone derivatives (1d–3d). In various pHs, based on ECE mechanism, the observed homogeneous rate constants (kobs) of cyclization reaction were estimated by comparing the experimental cyclic voltammetric responses with the digital-simulated results. Also, the cyclization rate constants (kcyc) were calculated using microscopic acidic dissociation constant of ammonium groups. The significant differences in electrochemical behavior, kobs and kcyc, of L-dopa (2) and methyldopa (3) with dopamine (1) are due to the effects of the side chain carboxyl group. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 37: 17–24, 2005
BMC Ophthalmology, 2004
The aim of this study was to identify risk factors for the development of retinopathy and microal... more The aim of this study was to identify risk factors for the development of retinopathy and microalbuminuria and their correlation in type II diabetic patients.
Anti-thyroid peroxidase antibody (anti-TPO) is a member of thyroid autoantibodies is important in... more Anti-thyroid peroxidase antibody (anti-TPO) is a member of thyroid autoantibodies is important in inducing and also diagnosing autoimmune thyroid diseases. Thyroid autoimmunity can cause several forms of thyroiditis and abnormal thyroid functions, ranging from hypothyroidism to hyperthyroidism. Evaluation of the relationship between serum levels of anti-TPO and thyroid hormones (T3, T4 and TSH) was aimed. In 2425 persons suspected of thyroid disease and referred to Yazd central medical laboratory by physicians during 2 years, the concentrations of serum anti-TPO and also serum T3, T4 and TSH were measured using ELISA and RIA methods, respectively. Most of the patients (53.53%) were between 20 to 39 years old. Females comprised 88.04% (2135 patients) and the remaining 290 patients (11.96%) were male. The differences between patients who had normal anti-TPO and those who had more than normal anti-TPO in different levels of T3, T4 and TSH were significant (p<0.0001). The correlation between TSH and T4 in patients who had abnormal anti-TPO were significant (r= 0.107, P=0.04, r=-0.160, p=0.002, respectively). Anti-TPO is a good marker for patients with autoimmune hypothyroidism who have high levels of TSH or less than normal T3 or T4 and there is a significant correlation between anti-TPO and both TSH and T4.