Shiferaw Garoma - Profile on Academia.edu (original) (raw)
Papers by Shiferaw Garoma
A study on structural behaviour of CFRP laminated concrete beam with partial replacement of fine aggregate by PET granules
Journal of Building Pathology and Rehabilitation
A study on structural behaviour of CFRP laminated concrete beam with partial replacement of fine aggregate by PET granules
Journal of Building Pathology and Rehabilitation
Technologies
In this paper, the self-curing process was considered and found to be a better alternative to the... more In this paper, the self-curing process was considered and found to be a better alternative to the conventional curing process for concrete structures in Ethiopia. It is well known that water plays a significant role in the curing process of preparing concrete in the construction industry. A good quality water is required for the conventional curing process, but that is scarce in Ethiopia. Curing concrete for bridges and roads is difficult in Ethiopia due to the poor quality and scarcity of water. In this study, Polyethylene Glycol (PEG) 600, a self-curing process, is considered as an alternative. Using the M40 Grade mix, four different percentages of PEG-600, 0.0, 0.5, 1.0, and 1.5 of cement weight, were studied, and the specimens were tested. Here, M40 grade stands for “a concrete mix with a characteristic compressive strength of 40 N/mm2, i.e., 40 Newton per square millimeter”. Additionally, the mechanical strengths and properties of both conventional and self-cured processed conc...
This study was carried out to generate information on some productive and reproductive performanc... more This study was carried out to generate information on some productive and reproductive performance of Kereyu Sanga cattle in their home tract. The data was collected through questionnaire from 114 Kereyu Sanga cattle owners. Fifty four third parity lactating Kereyu Sanga cows were randomly selected for milk yield measurement. According to the respondents, the mean age at puberty, age at first calving, lactation length and calving interval for Kereyu Sanga cows were 47.5, 54.1, 8.5 and 18 months, respectively, with associated lifetime calf crop production of 7.1 and reproductive lifespan of 13.2 year. The overall fertility rate of Kereyu Sanga cows was 55.4%. The mean reported age at puberty and reproductive life span for Kereyu Sanga bulls were 49 months and 9.2 years, respectively. The mean reported daily and lactation milk yield of Kereyu sanga cows were 1.8 and 463.1 L, respectively, whereas the mean measured third parity daily and lactation milk yield were 2 and 543 L, respectiv...
Journal of Cell and Animal Biology, Feb 28, 2014
This study was carried out to generate information on some productive and reproductive performanc... more This study was carried out to generate information on some productive and reproductive performance of Kereyu Sanga cattle in their home tract. The data was collected through questionnaire from 114 Kereyu Sanga cattle owners. Fifty four third parity lactating Kereyu Sanga cows were randomly selected for milk yield measurement. According to the respondents, the mean age at puberty, age at first calving, lactation length and calving interval for Kereyu Sanga cows were 47.5, 54.1, 8.5 and 18 months, respectively, with associated lifetime calf crop production of 7.1 and reproductive lifespan of 13.2 year. The overall fertility rate of Kereyu Sanga cows was 55.4%. The mean reported age at puberty and reproductive life span for Kereyu Sanga bulls were 49 months and 9.2 years, respectively. The mean reported daily and lactation milk yield of Kereyu sanga cows were 1.8 and 463.1 L, respectively, whereas the mean measured third parity daily and lactation milk yield were 2 and 543 L, respectively. The reported variations both in some productive and reproductive performance and the observed variations in measured milk yield among the individual animals under such harsh environment indicate the possibility of improving the performance of this adapted Sanga breed through selection in their home tract so as to enhance their contribution towards poverty alleviation.
The FASEB Journal, 2011
The insulin-like growth factor 1 receptor (IGF-1R) is involved in transformation, survival, mitog... more The insulin-like growth factor 1 receptor (IGF-1R) is involved in transformation, survival, mitogenesis and differentiation. It is overexpressed in many tumors and a validated target for anticancer therapy. In cell-free systems, polypyrimidic peptide nucleic acids (PNAs) can form triplex-like structures with messenger RNAs and halt the ribosomal machinery during the translation elongation. A 17-mer PNA that formed a PNA 2 : mRNA complex with a purine-rich sequence located in the coding region of IGF-1R mRNA induced the synthesis of a truncated IGF-1R in vitro. This PNA down-regulated expression of the receptor by 70 -80% in prostate cancer cells without affecting insulin receptor expression that exhibits high homology with IGF-1R. Inhibition occurs at the translational level, since the IGF-1R mRNA level measured by quantitative RT-PCR was not affected by PNA treatment. In addition, IGF-1R knockdown by PNA led to an attenuation of phosphorylation of downstream signaling pathways, PI3K/AKT and MAPK, involved in survival and mitogenesis and also to a decrease in cell transformation. Of the steric blockers tested, which included phosphorodiamidate morpholino oligomers and locked nucleic acids, PNA was unique in its ability to form triplex structures with mRNA and to arrest translation elon-
African Journal of Agricultural Research, Nov 21, 2013
The study was carried out in Fentalle district of east Shoa zone of Oromia, southern part of the ... more The study was carried out in Fentalle district of east Shoa zone of Oromia, southern part of the northern Rift Valley of Ethiopia, to evaluate pastoralists and agro-pastoralists preferences for cattle breed and traits. The study areas are characterized by low input-output, weak infrastructure and high environmental stress. The data was collected through questionnaire from 114 Kereyu cattle owners and analyzed using descriptive statistics, including summary statistics and frequency counts. The majority of the respondents had particular preferences for Kereyu Sanga cattle (69.3%) along with their specific traits. Milk yield (95.6%), coat color (85.1%), drought resistance (72.5%), fertility (71.1%), heat tolerance (63.1%) and disease resistance (60.5%) were the most frequently reported preferred traits by the respondents. The ecological significance of coat color is widely recognized by the cattle keepers in the study areas. Such information can help assure that breed improvement interventions are consistent with the needs of the intended beneficiaries.
Analysis of Stress- Strain and Deflection of Flexible Pavements Using Finite Element Method Case Study on Bako-Nekemte Road
In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are fle... more In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are flexible pavements. Nowadays, the failure of surface of flexible pavement roads are common before the expected design period. For the example Bako-Nekemte road/ has become a critical issue in our country. The most common parameters that cause stress, strain and deflection of the roads are loads and pressures that come from vehicles. Moreover, modulus of elasticity, Poisson’s ratio and thickness of each layer needs to be characterized. Further, the load magnitude, contact pressure (or load radius) and location are defined for each load (wheel) considered. Finite element method (FEM) is a numerical analysis technique to obtain the stress-strain and deflection of each pavement layers. Analytical method usually uses layers thickness, loads, elastic modulus and Poisson’s ratio of the pavement materials as design parameters. The objective of this research was to study the sensitivity of the road ...
English
Journal of Cell and Animal Biology, Feb 28, 2014
English
Journal of Cell and Animal Biology, 2014
Existing bridges are being subjected to an ever increasing volume of heavy truck traffic, and inc... more Existing bridges are being subjected to an ever increasing volume of heavy truck traffic, and increasing number of vehicles. This may reduce life and strength they were designed for. Due to this performance declining, it is customary to determine the available strength and remaining life in existing bridges as it provides evidence if the bridge function safely over a specified design life.
In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are fle... more In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are flexible pavements. Nowadays, the failure of surface of flexible pavement roads are common before the expected design period. For the example Bako-Nekemte road/ has become a critical issue in our country. The most common parameters that cause stress, strain and deflection of the roads are loads and pressures that come from vehicles. Moreover, modulus of elasticity, Poisson's ratio and thickness of each layer needs to be characterized. Further, the load magnitude, contact pressure (or load radius) and location are defined for each load (wheel) considered. Finite element method (FEM) is a numerical analysis technique to obtain the stress-strain and deflection of each pavement layers. Analytical method usually uses layers thickness, loads, elastic modulus and Poisson's ratio of the pavement materials as design parameters. The objective of this research was to study the sensitivity of the road parameters in analyzing the major causes of failure in asphalt pavement layers fatigue cracking and rutting deformation which came due to the critical tensile strains at the bottom of the asphalt layer and the critical compressive strains on the top of subgrade using the finite element method by relating the standard specification of ERA and laboratory test result. This thesis studied the analysis of stress-strain and deflection of flexible pavements using Everstress finite element method. The Ever stress program will take into account any stress dependent stiffness characteristics. This thesis dealt with ways to reduce deflections by varying the design configuration, such as increasing the HMA modulus, the base modulus, sub base modulus, the subgrade modulus and increasing thickness of each layers. Based on type of materials to use the value of elastic modulus and poison's ratio are various in each layers, in layer 1 is varied from 1500 to 3500 MPa, in layer 2 is varied from 200 to 1000MPa, in layer 3 is varied from 100 to 250 MPa and in layer 4 is varied from 20MPa to 150MPa.
In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are fle... more In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are flexible pavements. Nowadays, the failure of surface of flexible pavement roads are common before the expected design period. For the example Bako-Nekemte road/ has become a critical issue in our country. The most common parameters that cause stress, strain and deflection of the roads are loads and pressures that come from vehicles. Moreover, modulus of elasticity, Poisson's ratio and thickness of each layer needs to be characterized. Further, the load magnitude, contact pressure (or load radius) and location are defined for each load (wheel) considered. Finite element method (FEM) is a numerical analysis technique to obtain the stress-strain and deflection of each pavement layers. Analytical method usually uses layers thickness, loads, elastic modulus and Poisson's ratio of the pavement materials as design parameters. The objective of this research was to study the sensitivity of the road parameters in analyzing the major causes of failure in asphalt pavement layers fatigue cracking and rutting deformation which came due to the critical tensile strains at the bottom of the asphalt layer and the critical compressive strains on the top of subgrade using the finite element method by relating the standard specification of ERA and laboratory test result. This thesis studied the analysis of stress-strain and deflection of flexible pavements using Everstress finite element method. The Ever stress program will take into account any stress dependent stiffness characteristics. This thesis dealt with ways to reduce deflections by varying the design configuration, such as increasing the HMA modulus, the base modulus, sub base modulus, the subgrade modulus and increasing thickness of each layers. Based on type of materials to use the value of elastic modulus and poison's ratio are various in each layers, in layer 1 is varied from 1500 to 3500 MPa, in layer 2 is varied from 200 to 1000MPa, in layer 3 is varied from 100 to 250 MPa and in layer 4 is varied from 20MPa to 150MPa.
A study on structural behaviour of CFRP laminated concrete beam with partial replacement of fine aggregate by PET granules
Journal of Building Pathology and Rehabilitation
A study on structural behaviour of CFRP laminated concrete beam with partial replacement of fine aggregate by PET granules
Journal of Building Pathology and Rehabilitation
Technologies
In this paper, the self-curing process was considered and found to be a better alternative to the... more In this paper, the self-curing process was considered and found to be a better alternative to the conventional curing process for concrete structures in Ethiopia. It is well known that water plays a significant role in the curing process of preparing concrete in the construction industry. A good quality water is required for the conventional curing process, but that is scarce in Ethiopia. Curing concrete for bridges and roads is difficult in Ethiopia due to the poor quality and scarcity of water. In this study, Polyethylene Glycol (PEG) 600, a self-curing process, is considered as an alternative. Using the M40 Grade mix, four different percentages of PEG-600, 0.0, 0.5, 1.0, and 1.5 of cement weight, were studied, and the specimens were tested. Here, M40 grade stands for “a concrete mix with a characteristic compressive strength of 40 N/mm2, i.e., 40 Newton per square millimeter”. Additionally, the mechanical strengths and properties of both conventional and self-cured processed conc...
This study was carried out to generate information on some productive and reproductive performanc... more This study was carried out to generate information on some productive and reproductive performance of Kereyu Sanga cattle in their home tract. The data was collected through questionnaire from 114 Kereyu Sanga cattle owners. Fifty four third parity lactating Kereyu Sanga cows were randomly selected for milk yield measurement. According to the respondents, the mean age at puberty, age at first calving, lactation length and calving interval for Kereyu Sanga cows were 47.5, 54.1, 8.5 and 18 months, respectively, with associated lifetime calf crop production of 7.1 and reproductive lifespan of 13.2 year. The overall fertility rate of Kereyu Sanga cows was 55.4%. The mean reported age at puberty and reproductive life span for Kereyu Sanga bulls were 49 months and 9.2 years, respectively. The mean reported daily and lactation milk yield of Kereyu sanga cows were 1.8 and 463.1 L, respectively, whereas the mean measured third parity daily and lactation milk yield were 2 and 543 L, respectiv...
Journal of Cell and Animal Biology, Feb 28, 2014
This study was carried out to generate information on some productive and reproductive performanc... more This study was carried out to generate information on some productive and reproductive performance of Kereyu Sanga cattle in their home tract. The data was collected through questionnaire from 114 Kereyu Sanga cattle owners. Fifty four third parity lactating Kereyu Sanga cows were randomly selected for milk yield measurement. According to the respondents, the mean age at puberty, age at first calving, lactation length and calving interval for Kereyu Sanga cows were 47.5, 54.1, 8.5 and 18 months, respectively, with associated lifetime calf crop production of 7.1 and reproductive lifespan of 13.2 year. The overall fertility rate of Kereyu Sanga cows was 55.4%. The mean reported age at puberty and reproductive life span for Kereyu Sanga bulls were 49 months and 9.2 years, respectively. The mean reported daily and lactation milk yield of Kereyu sanga cows were 1.8 and 463.1 L, respectively, whereas the mean measured third parity daily and lactation milk yield were 2 and 543 L, respectively. The reported variations both in some productive and reproductive performance and the observed variations in measured milk yield among the individual animals under such harsh environment indicate the possibility of improving the performance of this adapted Sanga breed through selection in their home tract so as to enhance their contribution towards poverty alleviation.
The FASEB Journal, 2011
The insulin-like growth factor 1 receptor (IGF-1R) is involved in transformation, survival, mitog... more The insulin-like growth factor 1 receptor (IGF-1R) is involved in transformation, survival, mitogenesis and differentiation. It is overexpressed in many tumors and a validated target for anticancer therapy. In cell-free systems, polypyrimidic peptide nucleic acids (PNAs) can form triplex-like structures with messenger RNAs and halt the ribosomal machinery during the translation elongation. A 17-mer PNA that formed a PNA 2 : mRNA complex with a purine-rich sequence located in the coding region of IGF-1R mRNA induced the synthesis of a truncated IGF-1R in vitro. This PNA down-regulated expression of the receptor by 70 -80% in prostate cancer cells without affecting insulin receptor expression that exhibits high homology with IGF-1R. Inhibition occurs at the translational level, since the IGF-1R mRNA level measured by quantitative RT-PCR was not affected by PNA treatment. In addition, IGF-1R knockdown by PNA led to an attenuation of phosphorylation of downstream signaling pathways, PI3K/AKT and MAPK, involved in survival and mitogenesis and also to a decrease in cell transformation. Of the steric blockers tested, which included phosphorodiamidate morpholino oligomers and locked nucleic acids, PNA was unique in its ability to form triplex structures with mRNA and to arrest translation elon-
African Journal of Agricultural Research, Nov 21, 2013
The study was carried out in Fentalle district of east Shoa zone of Oromia, southern part of the ... more The study was carried out in Fentalle district of east Shoa zone of Oromia, southern part of the northern Rift Valley of Ethiopia, to evaluate pastoralists and agro-pastoralists preferences for cattle breed and traits. The study areas are characterized by low input-output, weak infrastructure and high environmental stress. The data was collected through questionnaire from 114 Kereyu cattle owners and analyzed using descriptive statistics, including summary statistics and frequency counts. The majority of the respondents had particular preferences for Kereyu Sanga cattle (69.3%) along with their specific traits. Milk yield (95.6%), coat color (85.1%), drought resistance (72.5%), fertility (71.1%), heat tolerance (63.1%) and disease resistance (60.5%) were the most frequently reported preferred traits by the respondents. The ecological significance of coat color is widely recognized by the cattle keepers in the study areas. Such information can help assure that breed improvement interventions are consistent with the needs of the intended beneficiaries.
Analysis of Stress- Strain and Deflection of Flexible Pavements Using Finite Element Method Case Study on Bako-Nekemte Road
In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are fle... more In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are flexible pavements. Nowadays, the failure of surface of flexible pavement roads are common before the expected design period. For the example Bako-Nekemte road/ has become a critical issue in our country. The most common parameters that cause stress, strain and deflection of the roads are loads and pressures that come from vehicles. Moreover, modulus of elasticity, Poisson’s ratio and thickness of each layer needs to be characterized. Further, the load magnitude, contact pressure (or load radius) and location are defined for each load (wheel) considered. Finite element method (FEM) is a numerical analysis technique to obtain the stress-strain and deflection of each pavement layers. Analytical method usually uses layers thickness, loads, elastic modulus and Poisson’s ratio of the pavement materials as design parameters. The objective of this research was to study the sensitivity of the road ...
English
Journal of Cell and Animal Biology, Feb 28, 2014
English
Journal of Cell and Animal Biology, 2014
Existing bridges are being subjected to an ever increasing volume of heavy truck traffic, and inc... more Existing bridges are being subjected to an ever increasing volume of heavy truck traffic, and increasing number of vehicles. This may reduce life and strength they were designed for. Due to this performance declining, it is customary to determine the available strength and remaining life in existing bridges as it provides evidence if the bridge function safely over a specified design life.
In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are fle... more In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are flexible pavements. Nowadays, the failure of surface of flexible pavement roads are common before the expected design period. For the example Bako-Nekemte road/ has become a critical issue in our country. The most common parameters that cause stress, strain and deflection of the roads are loads and pressures that come from vehicles. Moreover, modulus of elasticity, Poisson's ratio and thickness of each layer needs to be characterized. Further, the load magnitude, contact pressure (or load radius) and location are defined for each load (wheel) considered. Finite element method (FEM) is a numerical analysis technique to obtain the stress-strain and deflection of each pavement layers. Analytical method usually uses layers thickness, loads, elastic modulus and Poisson's ratio of the pavement materials as design parameters. The objective of this research was to study the sensitivity of the road parameters in analyzing the major causes of failure in asphalt pavement layers fatigue cracking and rutting deformation which came due to the critical tensile strains at the bottom of the asphalt layer and the critical compressive strains on the top of subgrade using the finite element method by relating the standard specification of ERA and laboratory test result. This thesis studied the analysis of stress-strain and deflection of flexible pavements using Everstress finite element method. The Ever stress program will take into account any stress dependent stiffness characteristics. This thesis dealt with ways to reduce deflections by varying the design configuration, such as increasing the HMA modulus, the base modulus, sub base modulus, the subgrade modulus and increasing thickness of each layers. Based on type of materials to use the value of elastic modulus and poison's ratio are various in each layers, in layer 1 is varied from 1500 to 3500 MPa, in layer 2 is varied from 200 to 1000MPa, in layer 3 is varied from 100 to 250 MPa and in layer 4 is varied from 20MPa to 150MPa.
In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are fle... more In Ethiopia the failure of roads are before handover period. Most roads found in Ethiopia are flexible pavements. Nowadays, the failure of surface of flexible pavement roads are common before the expected design period. For the example Bako-Nekemte road/ has become a critical issue in our country. The most common parameters that cause stress, strain and deflection of the roads are loads and pressures that come from vehicles. Moreover, modulus of elasticity, Poisson's ratio and thickness of each layer needs to be characterized. Further, the load magnitude, contact pressure (or load radius) and location are defined for each load (wheel) considered. Finite element method (FEM) is a numerical analysis technique to obtain the stress-strain and deflection of each pavement layers. Analytical method usually uses layers thickness, loads, elastic modulus and Poisson's ratio of the pavement materials as design parameters. The objective of this research was to study the sensitivity of the road parameters in analyzing the major causes of failure in asphalt pavement layers fatigue cracking and rutting deformation which came due to the critical tensile strains at the bottom of the asphalt layer and the critical compressive strains on the top of subgrade using the finite element method by relating the standard specification of ERA and laboratory test result. This thesis studied the analysis of stress-strain and deflection of flexible pavements using Everstress finite element method. The Ever stress program will take into account any stress dependent stiffness characteristics. This thesis dealt with ways to reduce deflections by varying the design configuration, such as increasing the HMA modulus, the base modulus, sub base modulus, the subgrade modulus and increasing thickness of each layers. Based on type of materials to use the value of elastic modulus and poison's ratio are various in each layers, in layer 1 is varied from 1500 to 3500 MPa, in layer 2 is varied from 200 to 1000MPa, in layer 3 is varied from 100 to 250 MPa and in layer 4 is varied from 20MPa to 150MPa.