Mohamed Hassan - Academia.edu (original) (raw)

Papers by Mohamed Hassan

Research paper thumbnail of Novel Temperature Control Technique for a Medicinal Herb Dryer System Powered by a Photovoltaic Array

International Journal of Green Energy, 2005

Each plant has its own optimal drying temperature, especially for the medicinal herbs, because th... more Each plant has its own optimal drying temperature, especially for the medicinal herbs, because they are sensitive to heat. If the drying temperature becomes more than the optimal value, some chemical reactions will occur and influence the quality of the dried herb, such as color, taste, and aroma. While if the drying temperature becomes lower than the optimal value, the drying process will slow down, and consequently an expected degradation in the quality of the herb may occur, due to insects and fungi infestation which increase in moist conditions. This paper presents a new temperature control technique for a medicinal herb dryer system. The technique fixes the drying temperature of the medicinal herbs at 40°C, even in cases of rapidly changing atmospheric conditions. The control of the dryer temperature is achieved through using the proportional integral (PI) controller. The designed dryer contains two systems, which are the thermal and the electrical systems. The thermal system is designed to heat the drying air by using solar energy and bio-gas fuel. Whereas the electrical system, which contains a photovoltaic (PV) modules and a battery, is designed to supply the different electrical loads of the dryer system. The control technique is investigated through simulation work by using MATLAB-SIMULINK. The simulation results indicate the high capability of the proposed technique in controlling the drying temperature, even in cases of rapidly changing atmospheric conditions.

Research paper thumbnail of Biochemical significance of autoantibody titers against oxidized low-density lipoprotein in patients with coronary heart disease

Page 1. Biochemical significance of autoantibody titers against oxidized low-density lipoprotein ... more Page 1. Biochemical significance of autoantibody titers against oxidized low-density lipoprotein in patients with coronary heart disease MAHMOUD ,I. NASR1 ;SHADEN, M. HANAFY1; M OSMAN 2; EHAB M. ABDEL-FATTAH 3 ; DALIA A 4 .AND HASSAN M. 1 ...

Research paper thumbnail of Name of journal: World Journal of Gastroenterology ESPS Manuscript NO: 7203 Columns: TOPIC HIGHLIGHTS

Research paper thumbnail of The Immunomoduatory Effect of Toll-Like Receptors 7/8 ligand (TLRs 7/8) in Allergic Rhinitis Patients

Research paper thumbnail of Fatigue fracture behavior of MEMS Cu thin films

Various MEMS devices have been developed based on the advances on micro-electromechanical systems... more Various MEMS devices have been developed based on the advances on micro-electromechanical systems technologies. It has become important to ensure their performance and reliability. The fatigue behavior of Cu thin films widely used in MEMS devices are essential to evaluate performance and reliability of these devices, and it has been well known that fatigue behavior of thin films are different from those of bulk materials. As model specimens to investigate the fatigue behavior of Cu thin films, pure copper films with thickness of 100 µm were bonded with epoxy resin and directly diffused to steel base plates. The fatigue crack initiation and propagation from the notch root of the specimen were faster for the epoxy-bounded film than for diffused bounding specimen. Moreover, the fatigue crack initiation life on film surface is found to be higher in case of diffusion-bounding. On the other hand, crack initiation and propagation also increased as the stress amplitude increase while decreased as mean stress increase. Roughness of surface films has been measured by laser microscope. These results showed the effect of different stress amplitudes and mean stresses on the fatigue behavior of Cu thin film.

Research paper thumbnail of An Improved K-means Document Clustering using Wikipedia Hierarchical Ontology

Text document clustering is one of the crucial tasks in text mining. It is used in many different... more Text document clustering is one of the crucial tasks in text mining. It is used in many different text mining applications. One of the most commonly used algorithms for document clustering is the k-means algorithm, the main drawback of which is that its output performance is very sensitive to its initial clusters' centroids. In this work, we present a technique to initialize the centroids based on background knowledge structure extracted from one of the largest online knowledge repositories: Wikipedia. Results show that the proposed model is efficient, and promising, as it outperforms the accuracy of the conventional k-means clustering, as well as other conventional algorithms for document clustering.

Research paper thumbnail of Hepatitis C virus core protein induces the expression of map kinase phosphatase (MKP-1) and map kinases (JNK and P38) in HEPG2 cells

Recurrence of hepatitis B virus (HBV) infection contributes to graft loss in patients undergoing ... more Recurrence of hepatitis B virus (HBV) infection contributes to graft loss in patients undergoing transplantation for HBV-related disease. Furthermore, immenosuppressien augments viral activity. Immune modulation using IFN~ has had only limited success. Recent evidence suggests that a number of viral diseases affect dendritic cell (DC) function. Aim: To define targets for potential immune modulation for therapy of hepatitis B infectien, we assessed DC from patients with chronic HBV infection-Methods: De were propagated in the presence of GM-CSF and IL-4 from HBV-infected patients treated with nucleoside analogs. Phenotypic cha-

Research paper thumbnail of Hepatitis C virus non-structural protein (NS3) interacts with MAPK pathway JNK in HepG2 cells

Research paper thumbnail of Tightly regulated expression of HCV-NS3 protein induces the activity of the nuclear transcription factor NF-κB in liver cells

Research paper thumbnail of Recombinant human interleukin-11 inhibits NF-kB and AP-1 activation in pancreatic islets and prevents diabetes induced with multiple low doses of streptozotocin

Research paper thumbnail of Literatur zu Kapitel 3.7: Molekulare Marker

Research paper thumbnail of ORIGINAL RESEARCH ARTICLES-Immunology/Microbiology/Virology-Interleukin-11 Inhibits NF-kB and AP-1 Activation in Islets and Prevents Diabetes Induced with Streptozotocin in Mice

Research paper thumbnail of Localization of apoptosis-regulating proteins as an important determinant of cancer cell fate

Research paper thumbnail of Post-translational and transcriptional modifications induced by hyperthermia or paclitaxel treatment of human lung cancer cells

Research paper thumbnail of Topoisomerase I inhibitor (irinotecan hydrochloride)

Research paper thumbnail of Significance of the way to dissociate Bax from Bcl-2 after the treatment of human lung cancer cells in the decision of the fate of cancer cells

Apoptosis is induced by many kinds of apoptotic stimuli. As apoptotic pathways are very complicat... more Apoptosis is induced by many kinds of apoptotic stimuli. As apoptotic pathways are very complicated, it is very important to analyze these apoptotic pathways to map out the strategy of cancer treatment. Therefore, we mainly focused on post-translational and ...

Research paper thumbnail of Induction of tumor necrosis factor alpha by hepatitis C virus (HCV) nonstructural protein 3 (NS3) in HepG2 cells is both AP-1 and NF-kappa B-dependent activation

Research paper thumbnail of 309. STAT5 Phosphorylation in Malignant Melanoma Is Mediated through SRC and JAK-1 Kinases and Exerts Anti-Apoptotic Effects

Altered signaling pathways are key regulators of cellular functions in tumor cells. Constitutive ... more Altered signaling pathways are key regulators of cellular functions in tumor cells. Constitutive activation of signal transducer and activator of transcription (STAT) proteins, particularly STAT3 and STAT5, may be involved in tumor formation and progression. In the present study, we have investigated the role of STAT5 in cutaneous metastases of human malignant melanoma. In 13 of 21 (76%) human melanoma

Research paper thumbnail of STAT5 phosphorylation in malignant melanoma is mediated through SRC and JAK-1 kinases and exerts anti-apoptotic effects

Altered signaling pathways are key regulators of cellular functions in tumor cells. Constitutive ... more Altered signaling pathways are key regulators of cellular functions in tumor cells. Constitutive activation of signal transducer and activator of transcription (STAT)3 and -5 may be involved in tumor formation and progression. We have investigated the role of STAT5 in cutaneous melanoma metastases using various RNA and protein techniques. In melanoma specimens, Stat5b transcripts were upregulated approximately 3.8-fold. In 13 of 21 (62%) human melanoma metastases, STAT5 was phosphorylated in comparison to normal human melanocytes and benign nevi. The STAT5 target gene Bcl-2 was frequently upregulated. The investigation of the underlying mechanism revealed specific STAT5 activation by recombinant human epidermal growth factor (rEGF). rEGF-induced activation of STAT5 occurred in vitro through the non-receptor tyrosine kinases transforming gene (src) of Rous Sarcoma virus and Janus kinase 1. Inhibition of Stat5b expression by small interfering RNA strongly reduced the expression of Bcl-2 and led to decreased cell viability and increased apoptosis in the melanoma cell lines A375 and BLM. Transfection with dominant-negative Stat5b caused enhanced cell death and G1 arrest in A375 cells. Our study identifies phosphorylated STAT5 in melanoma and shows regulation through rEGF; STAT5 may thus act as a survival factor for growth of human melanoma and may represent a potential target for molecular therapy.

Research paper thumbnail of Signaling networks in cutaneous melanoma metastasis identified by cDNA microarrays

Background: Melanoma is a complex multigenic disease, susceptibility to which is determined by se... more Background: Melanoma is a complex multigenic disease, susceptibility to which is determined by several parallel and stepwise progressive pathways affecting growth control, differentiation, cell adhesion, and survival. Melanoma and human cancers in general undergo a continuous development from benign to malignant states, as most thoroughly documented in the multistep mole-tomelanoma transition.

Research paper thumbnail of Novel Temperature Control Technique for a Medicinal Herb Dryer System Powered by a Photovoltaic Array

International Journal of Green Energy, 2005

Each plant has its own optimal drying temperature, especially for the medicinal herbs, because th... more Each plant has its own optimal drying temperature, especially for the medicinal herbs, because they are sensitive to heat. If the drying temperature becomes more than the optimal value, some chemical reactions will occur and influence the quality of the dried herb, such as color, taste, and aroma. While if the drying temperature becomes lower than the optimal value, the drying process will slow down, and consequently an expected degradation in the quality of the herb may occur, due to insects and fungi infestation which increase in moist conditions. This paper presents a new temperature control technique for a medicinal herb dryer system. The technique fixes the drying temperature of the medicinal herbs at 40°C, even in cases of rapidly changing atmospheric conditions. The control of the dryer temperature is achieved through using the proportional integral (PI) controller. The designed dryer contains two systems, which are the thermal and the electrical systems. The thermal system is designed to heat the drying air by using solar energy and bio-gas fuel. Whereas the electrical system, which contains a photovoltaic (PV) modules and a battery, is designed to supply the different electrical loads of the dryer system. The control technique is investigated through simulation work by using MATLAB-SIMULINK. The simulation results indicate the high capability of the proposed technique in controlling the drying temperature, even in cases of rapidly changing atmospheric conditions.

Research paper thumbnail of Biochemical significance of autoantibody titers against oxidized low-density lipoprotein in patients with coronary heart disease

Page 1. Biochemical significance of autoantibody titers against oxidized low-density lipoprotein ... more Page 1. Biochemical significance of autoantibody titers against oxidized low-density lipoprotein in patients with coronary heart disease MAHMOUD ,I. NASR1 ;SHADEN, M. HANAFY1; M OSMAN 2; EHAB M. ABDEL-FATTAH 3 ; DALIA A 4 .AND HASSAN M. 1 ...

Research paper thumbnail of Name of journal: World Journal of Gastroenterology ESPS Manuscript NO: 7203 Columns: TOPIC HIGHLIGHTS

Research paper thumbnail of The Immunomoduatory Effect of Toll-Like Receptors 7/8 ligand (TLRs 7/8) in Allergic Rhinitis Patients

Research paper thumbnail of Fatigue fracture behavior of MEMS Cu thin films

Various MEMS devices have been developed based on the advances on micro-electromechanical systems... more Various MEMS devices have been developed based on the advances on micro-electromechanical systems technologies. It has become important to ensure their performance and reliability. The fatigue behavior of Cu thin films widely used in MEMS devices are essential to evaluate performance and reliability of these devices, and it has been well known that fatigue behavior of thin films are different from those of bulk materials. As model specimens to investigate the fatigue behavior of Cu thin films, pure copper films with thickness of 100 µm were bonded with epoxy resin and directly diffused to steel base plates. The fatigue crack initiation and propagation from the notch root of the specimen were faster for the epoxy-bounded film than for diffused bounding specimen. Moreover, the fatigue crack initiation life on film surface is found to be higher in case of diffusion-bounding. On the other hand, crack initiation and propagation also increased as the stress amplitude increase while decreased as mean stress increase. Roughness of surface films has been measured by laser microscope. These results showed the effect of different stress amplitudes and mean stresses on the fatigue behavior of Cu thin film.

Research paper thumbnail of An Improved K-means Document Clustering using Wikipedia Hierarchical Ontology

Text document clustering is one of the crucial tasks in text mining. It is used in many different... more Text document clustering is one of the crucial tasks in text mining. It is used in many different text mining applications. One of the most commonly used algorithms for document clustering is the k-means algorithm, the main drawback of which is that its output performance is very sensitive to its initial clusters' centroids. In this work, we present a technique to initialize the centroids based on background knowledge structure extracted from one of the largest online knowledge repositories: Wikipedia. Results show that the proposed model is efficient, and promising, as it outperforms the accuracy of the conventional k-means clustering, as well as other conventional algorithms for document clustering.

Research paper thumbnail of Hepatitis C virus core protein induces the expression of map kinase phosphatase (MKP-1) and map kinases (JNK and P38) in HEPG2 cells

Recurrence of hepatitis B virus (HBV) infection contributes to graft loss in patients undergoing ... more Recurrence of hepatitis B virus (HBV) infection contributes to graft loss in patients undergoing transplantation for HBV-related disease. Furthermore, immenosuppressien augments viral activity. Immune modulation using IFN~ has had only limited success. Recent evidence suggests that a number of viral diseases affect dendritic cell (DC) function. Aim: To define targets for potential immune modulation for therapy of hepatitis B infectien, we assessed DC from patients with chronic HBV infection-Methods: De were propagated in the presence of GM-CSF and IL-4 from HBV-infected patients treated with nucleoside analogs. Phenotypic cha-

Research paper thumbnail of Hepatitis C virus non-structural protein (NS3) interacts with MAPK pathway JNK in HepG2 cells

Research paper thumbnail of Tightly regulated expression of HCV-NS3 protein induces the activity of the nuclear transcription factor NF-κB in liver cells

Research paper thumbnail of Recombinant human interleukin-11 inhibits NF-kB and AP-1 activation in pancreatic islets and prevents diabetes induced with multiple low doses of streptozotocin

Research paper thumbnail of Literatur zu Kapitel 3.7: Molekulare Marker

Research paper thumbnail of ORIGINAL RESEARCH ARTICLES-Immunology/Microbiology/Virology-Interleukin-11 Inhibits NF-kB and AP-1 Activation in Islets and Prevents Diabetes Induced with Streptozotocin in Mice

Research paper thumbnail of Localization of apoptosis-regulating proteins as an important determinant of cancer cell fate

Research paper thumbnail of Post-translational and transcriptional modifications induced by hyperthermia or paclitaxel treatment of human lung cancer cells

Research paper thumbnail of Topoisomerase I inhibitor (irinotecan hydrochloride)

Research paper thumbnail of Significance of the way to dissociate Bax from Bcl-2 after the treatment of human lung cancer cells in the decision of the fate of cancer cells

Apoptosis is induced by many kinds of apoptotic stimuli. As apoptotic pathways are very complicat... more Apoptosis is induced by many kinds of apoptotic stimuli. As apoptotic pathways are very complicated, it is very important to analyze these apoptotic pathways to map out the strategy of cancer treatment. Therefore, we mainly focused on post-translational and ...

Research paper thumbnail of Induction of tumor necrosis factor alpha by hepatitis C virus (HCV) nonstructural protein 3 (NS3) in HepG2 cells is both AP-1 and NF-kappa B-dependent activation

Research paper thumbnail of 309. STAT5 Phosphorylation in Malignant Melanoma Is Mediated through SRC and JAK-1 Kinases and Exerts Anti-Apoptotic Effects

Altered signaling pathways are key regulators of cellular functions in tumor cells. Constitutive ... more Altered signaling pathways are key regulators of cellular functions in tumor cells. Constitutive activation of signal transducer and activator of transcription (STAT) proteins, particularly STAT3 and STAT5, may be involved in tumor formation and progression. In the present study, we have investigated the role of STAT5 in cutaneous metastases of human malignant melanoma. In 13 of 21 (76%) human melanoma

Research paper thumbnail of STAT5 phosphorylation in malignant melanoma is mediated through SRC and JAK-1 kinases and exerts anti-apoptotic effects

Altered signaling pathways are key regulators of cellular functions in tumor cells. Constitutive ... more Altered signaling pathways are key regulators of cellular functions in tumor cells. Constitutive activation of signal transducer and activator of transcription (STAT)3 and -5 may be involved in tumor formation and progression. We have investigated the role of STAT5 in cutaneous melanoma metastases using various RNA and protein techniques. In melanoma specimens, Stat5b transcripts were upregulated approximately 3.8-fold. In 13 of 21 (62%) human melanoma metastases, STAT5 was phosphorylated in comparison to normal human melanocytes and benign nevi. The STAT5 target gene Bcl-2 was frequently upregulated. The investigation of the underlying mechanism revealed specific STAT5 activation by recombinant human epidermal growth factor (rEGF). rEGF-induced activation of STAT5 occurred in vitro through the non-receptor tyrosine kinases transforming gene (src) of Rous Sarcoma virus and Janus kinase 1. Inhibition of Stat5b expression by small interfering RNA strongly reduced the expression of Bcl-2 and led to decreased cell viability and increased apoptosis in the melanoma cell lines A375 and BLM. Transfection with dominant-negative Stat5b caused enhanced cell death and G1 arrest in A375 cells. Our study identifies phosphorylated STAT5 in melanoma and shows regulation through rEGF; STAT5 may thus act as a survival factor for growth of human melanoma and may represent a potential target for molecular therapy.

Research paper thumbnail of Signaling networks in cutaneous melanoma metastasis identified by cDNA microarrays

Background: Melanoma is a complex multigenic disease, susceptibility to which is determined by se... more Background: Melanoma is a complex multigenic disease, susceptibility to which is determined by several parallel and stepwise progressive pathways affecting growth control, differentiation, cell adhesion, and survival. Melanoma and human cancers in general undergo a continuous development from benign to malignant states, as most thoroughly documented in the multistep mole-tomelanoma transition.