ABSTRACT Creep fatigue is an important property of structural materials for fast breeder reactors... more ABSTRACT Creep fatigue is an important property of structural materials for fast breeder reactors. In order to develop austenitic stainless steel having high resistance to creep fatigue, the effects of carbon, nitrogen, and molybdenum on creep rupture ductility at 550°C were investigated under the concept that creep fatigue endurance is proportional to creep rupture ductility. Strengthening by carbon results in much reduction of rupture ductility as a result of grain boundary embrittlement caused by coarse precipitation of carbides. Nitrogen increases rupture strength without reducing rupture ductility. Strengthening by molybdenum brings about a slight decrease in rupture ductility. On the bases of these results, 0.01%C-0.07%N-11%Ni-16.5%Cr-2.0%Mo steel is selected as a promising material for use in fast breeder reactors. It has higher rupture ductility and strength than conventional 316 steel. It was confirmed by creep fatigue tests that this steel has higher resistance to creep fatigue.
International Journal of Materials & Product Technology, 2014
Corrosion of ferritic stainless steels by the condensate of exhaust gases takes the form mainly o... more Corrosion of ferritic stainless steels by the condensate of exhaust gases takes the form mainly of localized corrosion, such as pitting or crevices. The localized corrosion of these stainless steels was evaluated using a simulated condensate. The usefulness of the method is assessed and a new index presented for the design of alloys, which takes account of environmental conditions.
The gene encoding glucosyltransferase responsible for water-insoluble glucan synthesis (GTF-I) of... more The gene encoding glucosyltransferase responsible for water-insoluble glucan synthesis (GTF-I) of Streptococcus sobrinus (formerly Streptococcus mutans 6715) was cloned, expressed, and sequenced. A gene bank from S. sobrinus 6715 DNA was constructed in vector pUC18 and screened with anti-GTF-I antibody to detect clones producing GTF-I peptide. Five immunopositive clones were isolated, all of which produced peptides that bound alpha-1,6 glucan. GTF-I activity was found in only two large peptides: one stretching over the full length of the GTF-I peptide and composed of about 1,600 amino acid residues (AB1 clone) and the other lacking about 80 N-terminal residues and about 260 C-terminal residues (AB2 clone). A deletion study of the AB2 clone indicated that specific glucan binding, which is essential for water-insoluble glucan synthesis, was lost prior to sucrase activity with an increase in deletion from the 3' end of the GTF-I gene. These results suggest that the GTF-I peptide co...
ABSTRACT Rubella virus is the causative agent of rubella. The symptoms are usually mild, and char... more ABSTRACT Rubella virus is the causative agent of rubella. The symptoms are usually mild, and characterized by a maculopapular rash and fever. However, rubella infection in pregnant women sometimes can result in the birth of infants with congenital rubella syndrome (CRS). Global efforts have been made to reduce and eliminate CRS. Although a reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay for detection of rubella virus has been reported, the primers contained several mismatched nucleotides with the genomes of currently circulating rubella virus strains. In the present study, a new RT-LAMP assay was established. The detection limit of this assay was 100–1000 PFU/reaction of viruses for all rubella genotypes, except for genotype 2C, which is not commonly found in the current era. Therefore, the new RT-LAMP assay can successfully detect all current rubella virus genotypes, and does not require sophisticated devices like TaqMan real-time PCR systems. This assay should be a useful assay for laboratory diagnosis of rubella and CRS.
Journal of the Egyptian National Cancer Institute, 2005
Loss of heterozygosity (LOH) in tumor samples is believed to be a marker for the absence of a fun... more Loss of heterozygosity (LOH) in tumor samples is believed to be a marker for the absence of a functional tumor suppressor gene. Non-random chromosome deletion and LOH at specific chromosomal regions are identified in a number of common human cancers including carcinoma of the bladder, which is considered the most predominant cancer in Egypt due to the prevalence of schistosomiasis. The main objective of the present study is to clarify the role of chromosomes 8 and 9 in the establishment and/or progression of schistosomiasis-related bladder cancer through detection of LOH of 8 microsatellite markers on both chromosomes. It also aims to compare the LOH pattern of the tested markers between schistosomiasis- associated and non schistosomiasis-associated bladder cancer. To achieve this purpose, DNA was extracted from the tumor specimens and the corresponding peripheral blood samples of 42 primary bladder cancer patients (schistosomal and non schistosomal). Twenty nine of these were diagn...
ABSTRACT Creep fatigue is an important property of structural materials for fast breeder reactors... more ABSTRACT Creep fatigue is an important property of structural materials for fast breeder reactors. In order to develop austenitic stainless steel having high resistance to creep fatigue, the effects of carbon, nitrogen, and molybdenum on creep rupture ductility at 550°C were investigated under the concept that creep fatigue endurance is proportional to creep rupture ductility. Strengthening by carbon results in much reduction of rupture ductility as a result of grain boundary embrittlement caused by coarse precipitation of carbides. Nitrogen increases rupture strength without reducing rupture ductility. Strengthening by molybdenum brings about a slight decrease in rupture ductility. On the bases of these results, 0.01%C-0.07%N-11%Ni-16.5%Cr-2.0%Mo steel is selected as a promising material for use in fast breeder reactors. It has higher rupture ductility and strength than conventional 316 steel. It was confirmed by creep fatigue tests that this steel has higher resistance to creep fatigue.
International Journal of Materials & Product Technology, 2014
Corrosion of ferritic stainless steels by the condensate of exhaust gases takes the form mainly o... more Corrosion of ferritic stainless steels by the condensate of exhaust gases takes the form mainly of localized corrosion, such as pitting or crevices. The localized corrosion of these stainless steels was evaluated using a simulated condensate. The usefulness of the method is assessed and a new index presented for the design of alloys, which takes account of environmental conditions.
The gene encoding glucosyltransferase responsible for water-insoluble glucan synthesis (GTF-I) of... more The gene encoding glucosyltransferase responsible for water-insoluble glucan synthesis (GTF-I) of Streptococcus sobrinus (formerly Streptococcus mutans 6715) was cloned, expressed, and sequenced. A gene bank from S. sobrinus 6715 DNA was constructed in vector pUC18 and screened with anti-GTF-I antibody to detect clones producing GTF-I peptide. Five immunopositive clones were isolated, all of which produced peptides that bound alpha-1,6 glucan. GTF-I activity was found in only two large peptides: one stretching over the full length of the GTF-I peptide and composed of about 1,600 amino acid residues (AB1 clone) and the other lacking about 80 N-terminal residues and about 260 C-terminal residues (AB2 clone). A deletion study of the AB2 clone indicated that specific glucan binding, which is essential for water-insoluble glucan synthesis, was lost prior to sucrase activity with an increase in deletion from the 3' end of the GTF-I gene. These results suggest that the GTF-I peptide co...
ABSTRACT Rubella virus is the causative agent of rubella. The symptoms are usually mild, and char... more ABSTRACT Rubella virus is the causative agent of rubella. The symptoms are usually mild, and characterized by a maculopapular rash and fever. However, rubella infection in pregnant women sometimes can result in the birth of infants with congenital rubella syndrome (CRS). Global efforts have been made to reduce and eliminate CRS. Although a reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay for detection of rubella virus has been reported, the primers contained several mismatched nucleotides with the genomes of currently circulating rubella virus strains. In the present study, a new RT-LAMP assay was established. The detection limit of this assay was 100–1000 PFU/reaction of viruses for all rubella genotypes, except for genotype 2C, which is not commonly found in the current era. Therefore, the new RT-LAMP assay can successfully detect all current rubella virus genotypes, and does not require sophisticated devices like TaqMan real-time PCR systems. This assay should be a useful assay for laboratory diagnosis of rubella and CRS.
Journal of the Egyptian National Cancer Institute, 2005
Loss of heterozygosity (LOH) in tumor samples is believed to be a marker for the absence of a fun... more Loss of heterozygosity (LOH) in tumor samples is believed to be a marker for the absence of a functional tumor suppressor gene. Non-random chromosome deletion and LOH at specific chromosomal regions are identified in a number of common human cancers including carcinoma of the bladder, which is considered the most predominant cancer in Egypt due to the prevalence of schistosomiasis. The main objective of the present study is to clarify the role of chromosomes 8 and 9 in the establishment and/or progression of schistosomiasis-related bladder cancer through detection of LOH of 8 microsatellite markers on both chromosomes. It also aims to compare the LOH pattern of the tested markers between schistosomiasis- associated and non schistosomiasis-associated bladder cancer. To achieve this purpose, DNA was extracted from the tumor specimens and the corresponding peripheral blood samples of 42 primary bladder cancer patients (schistosomal and non schistosomal). Twenty nine of these were diagn...
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