Publications

2022
Djellal D, Haddad S, Gasmi S, Chouit Z, Kebieche M, Hachemi M, HANFER M, Ferhat N, Bennoune O, Fetoui H, et al. CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.). The Journal of Microbiology, Biotechnology and Food Sciences [Internet]. 2022. Publisher's VersionAbstract
Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouringdownstream into food platesandcontributesto the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicityassessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performedin both brainareas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hippwith a values of 1,14 ± 0,04nmol/mg of proteins(pr)and 1,58 ± 0,09nmol/mg pr.respectively and a significant decrease in GSH(0,09 ± 0,01mmol/mg pr.in hipp and 0,08±0,01mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09UI/mg pr.in hipp14,54±1,46UI/mg pr.in str) , CAT (0,010±0,01UI/mg pr.in hipp and 0,005±0,004UI/mg pr.in str), GPx (0,01± 0,001nmol/mg pr.in both hippand str) and GST (23,73±1,68UI/mg pr.in hipp and 17,56± 1,04UI/mg pr.in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26μg/mlin str and 5,32 ± 1,08 μg/mlin hipp ) and Ca++( 2,26±0,06mmol/lin str and 2,32±0,07mmol/lin hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86ng/mg prin str and 14,8± 0,82ng/mg prin hipp), in the other hand the rates of caspase-9 were (278±14mAbs/mg pr.)in str and 212 ±24mAbs/mg pr.in hipp), caspase3 (184± 16mAbs/mg pr.)in str and 250 ±14mAbs/mg pr.in hipp), and BAX (0,926ng/mg prin str and 1,189ng/mg prin hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr.in str and 22,35± 1,77 nmol/min/mg pr.in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions whichwere prevented by bitter apricot kernels extract when associated with this pesticide.
Djellal D, Haddad S, Gasmi S, Chouit Z, Kebieche M, Hachemi M, HANFER M, Ferhat N, Bennoune O, Fetoui H, et al. CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.). The Journal of Microbiology, Biotechnology and Food Sciences [Internet]. 2022. Publisher's VersionAbstract
Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouringdownstream into food platesandcontributesto the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicityassessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performedin both brainareas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hippwith a values of 1,14 ± 0,04nmol/mg of proteins(pr)and 1,58 ± 0,09nmol/mg pr.respectively and a significant decrease in GSH(0,09 ± 0,01mmol/mg pr.in hipp and 0,08±0,01mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09UI/mg pr.in hipp14,54±1,46UI/mg pr.in str) , CAT (0,010±0,01UI/mg pr.in hipp and 0,005±0,004UI/mg pr.in str), GPx (0,01± 0,001nmol/mg pr.in both hippand str) and GST (23,73±1,68UI/mg pr.in hipp and 17,56± 1,04UI/mg pr.in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26μg/mlin str and 5,32 ± 1,08 μg/mlin hipp ) and Ca++( 2,26±0,06mmol/lin str and 2,32±0,07mmol/lin hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86ng/mg prin str and 14,8± 0,82ng/mg prin hipp), in the other hand the rates of caspase-9 were (278±14mAbs/mg pr.)in str and 212 ±24mAbs/mg pr.in hipp), caspase3 (184± 16mAbs/mg pr.)in str and 250 ±14mAbs/mg pr.in hipp), and BAX (0,926ng/mg prin str and 1,189ng/mg prin hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr.in str and 22,35± 1,77 nmol/min/mg pr.in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions whichwere prevented by bitter apricot kernels extract when associated with this pesticide.
Djellal D, Haddad S, Gasmi S, Chouit Z, Kebieche M, Hachemi M, HANFER M, Ferhat N, Bennoune O, Fetoui H, et al. CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.). The Journal of Microbiology, Biotechnology and Food Sciences [Internet]. 2022. Publisher's VersionAbstract
Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouringdownstream into food platesandcontributesto the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicityassessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performedin both brainareas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hippwith a values of 1,14 ± 0,04nmol/mg of proteins(pr)and 1,58 ± 0,09nmol/mg pr.respectively and a significant decrease in GSH(0,09 ± 0,01mmol/mg pr.in hipp and 0,08±0,01mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09UI/mg pr.in hipp14,54±1,46UI/mg pr.in str) , CAT (0,010±0,01UI/mg pr.in hipp and 0,005±0,004UI/mg pr.in str), GPx (0,01± 0,001nmol/mg pr.in both hippand str) and GST (23,73±1,68UI/mg pr.in hipp and 17,56± 1,04UI/mg pr.in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26μg/mlin str and 5,32 ± 1,08 μg/mlin hipp ) and Ca++( 2,26±0,06mmol/lin str and 2,32±0,07mmol/lin hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86ng/mg prin str and 14,8± 0,82ng/mg prin hipp), in the other hand the rates of caspase-9 were (278±14mAbs/mg pr.)in str and 212 ±24mAbs/mg pr.in hipp), caspase3 (184± 16mAbs/mg pr.)in str and 250 ±14mAbs/mg pr.in hipp), and BAX (0,926ng/mg prin str and 1,189ng/mg prin hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr.in str and 22,35± 1,77 nmol/min/mg pr.in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions whichwere prevented by bitter apricot kernels extract when associated with this pesticide.
Djellal D, Haddad S, Gasmi S, Chouit Z, Kebieche M, Hachemi M, HANFER M, Ferhat N, Bennoune O, Fetoui H, et al. CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.). The Journal of Microbiology, Biotechnology and Food Sciences [Internet]. 2022. Publisher's VersionAbstract
Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouringdownstream into food platesandcontributesto the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicityassessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performedin both brainareas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hippwith a values of 1,14 ± 0,04nmol/mg of proteins(pr)and 1,58 ± 0,09nmol/mg pr.respectively and a significant decrease in GSH(0,09 ± 0,01mmol/mg pr.in hipp and 0,08±0,01mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09UI/mg pr.in hipp14,54±1,46UI/mg pr.in str) , CAT (0,010±0,01UI/mg pr.in hipp and 0,005±0,004UI/mg pr.in str), GPx (0,01± 0,001nmol/mg pr.in both hippand str) and GST (23,73±1,68UI/mg pr.in hipp and 17,56± 1,04UI/mg pr.in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26μg/mlin str and 5,32 ± 1,08 μg/mlin hipp ) and Ca++( 2,26±0,06mmol/lin str and 2,32±0,07mmol/lin hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86ng/mg prin str and 14,8± 0,82ng/mg prin hipp), in the other hand the rates of caspase-9 were (278±14mAbs/mg pr.)in str and 212 ±24mAbs/mg pr.in hipp), caspase3 (184± 16mAbs/mg pr.)in str and 250 ±14mAbs/mg pr.in hipp), and BAX (0,926ng/mg prin str and 1,189ng/mg prin hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr.in str and 22,35± 1,77 nmol/min/mg pr.in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions whichwere prevented by bitter apricot kernels extract when associated with this pesticide.
Djellal D, Haddad S, Gasmi S, Chouit Z, Kebieche M, Hachemi M, HANFER M, Ferhat N, Bennoune O, Fetoui H, et al. CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.). The Journal of Microbiology, Biotechnology and Food Sciences [Internet]. 2022. Publisher's VersionAbstract
Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouringdownstream into food platesandcontributesto the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicityassessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performedin both brainareas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hippwith a values of 1,14 ± 0,04nmol/mg of proteins(pr)and 1,58 ± 0,09nmol/mg pr.respectively and a significant decrease in GSH(0,09 ± 0,01mmol/mg pr.in hipp and 0,08±0,01mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09UI/mg pr.in hipp14,54±1,46UI/mg pr.in str) , CAT (0,010±0,01UI/mg pr.in hipp and 0,005±0,004UI/mg pr.in str), GPx (0,01± 0,001nmol/mg pr.in both hippand str) and GST (23,73±1,68UI/mg pr.in hipp and 17,56± 1,04UI/mg pr.in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26μg/mlin str and 5,32 ± 1,08 μg/mlin hipp ) and Ca++( 2,26±0,06mmol/lin str and 2,32±0,07mmol/lin hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86ng/mg prin str and 14,8± 0,82ng/mg prin hipp), in the other hand the rates of caspase-9 were (278±14mAbs/mg pr.)in str and 212 ±24mAbs/mg pr.in hipp), caspase3 (184± 16mAbs/mg pr.)in str and 250 ±14mAbs/mg pr.in hipp), and BAX (0,926ng/mg prin str and 1,189ng/mg prin hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr.in str and 22,35± 1,77 nmol/min/mg pr.in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions whichwere prevented by bitter apricot kernels extract when associated with this pesticide.
Djellal D, Haddad S, Gasmi S, Chouit Z, Kebieche M, Hachemi M, HANFER M, Ferhat N, Bennoune O, Fetoui H, et al. CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.). The Journal of Microbiology, Biotechnology and Food Sciences [Internet]. 2022. Publisher's VersionAbstract
Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouringdownstream into food platesandcontributesto the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicityassessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performedin both brainareas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hippwith a values of 1,14 ± 0,04nmol/mg of proteins(pr)and 1,58 ± 0,09nmol/mg pr.respectively and a significant decrease in GSH(0,09 ± 0,01mmol/mg pr.in hipp and 0,08±0,01mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09UI/mg pr.in hipp14,54±1,46UI/mg pr.in str) , CAT (0,010±0,01UI/mg pr.in hipp and 0,005±0,004UI/mg pr.in str), GPx (0,01± 0,001nmol/mg pr.in both hippand str) and GST (23,73±1,68UI/mg pr.in hipp and 17,56± 1,04UI/mg pr.in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26μg/mlin str and 5,32 ± 1,08 μg/mlin hipp ) and Ca++( 2,26±0,06mmol/lin str and 2,32±0,07mmol/lin hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86ng/mg prin str and 14,8± 0,82ng/mg prin hipp), in the other hand the rates of caspase-9 were (278±14mAbs/mg pr.)in str and 212 ±24mAbs/mg pr.in hipp), caspase3 (184± 16mAbs/mg pr.)in str and 250 ±14mAbs/mg pr.in hipp), and BAX (0,926ng/mg prin str and 1,189ng/mg prin hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr.in str and 22,35± 1,77 nmol/min/mg pr.in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions whichwere prevented by bitter apricot kernels extract when associated with this pesticide.
Djellal D, Haddad S, Gasmi S, Chouit Z, Kebieche M, Hachemi M, HANFER M, Ferhat N, Bennoune O, Fetoui H, et al. CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.). The Journal of Microbiology, Biotechnology and Food Sciences [Internet]. 2022. Publisher's VersionAbstract
Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouringdownstream into food platesandcontributesto the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicityassessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performedin both brainareas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hippwith a values of 1,14 ± 0,04nmol/mg of proteins(pr)and 1,58 ± 0,09nmol/mg pr.respectively and a significant decrease in GSH(0,09 ± 0,01mmol/mg pr.in hipp and 0,08±0,01mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09UI/mg pr.in hipp14,54±1,46UI/mg pr.in str) , CAT (0,010±0,01UI/mg pr.in hipp and 0,005±0,004UI/mg pr.in str), GPx (0,01± 0,001nmol/mg pr.in both hippand str) and GST (23,73±1,68UI/mg pr.in hipp and 17,56± 1,04UI/mg pr.in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26μg/mlin str and 5,32 ± 1,08 μg/mlin hipp ) and Ca++( 2,26±0,06mmol/lin str and 2,32±0,07mmol/lin hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86ng/mg prin str and 14,8± 0,82ng/mg prin hipp), in the other hand the rates of caspase-9 were (278±14mAbs/mg pr.)in str and 212 ±24mAbs/mg pr.in hipp), caspase3 (184± 16mAbs/mg pr.)in str and 250 ±14mAbs/mg pr.in hipp), and BAX (0,926ng/mg prin str and 1,189ng/mg prin hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr.in str and 22,35± 1,77 nmol/min/mg pr.in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions whichwere prevented by bitter apricot kernels extract when associated with this pesticide.
Djellal D, Haddad S, Gasmi S, Chouit Z, Kebieche M, Hachemi M, HANFER M, Ferhat N, Bennoune O, Fetoui H, et al. CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.). The Journal of Microbiology, Biotechnology and Food Sciences [Internet]. 2022. Publisher's VersionAbstract
Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouringdownstream into food platesandcontributesto the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicityassessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performedin both brainareas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hippwith a values of 1,14 ± 0,04nmol/mg of proteins(pr)and 1,58 ± 0,09nmol/mg pr.respectively and a significant decrease in GSH(0,09 ± 0,01mmol/mg pr.in hipp and 0,08±0,01mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09UI/mg pr.in hipp14,54±1,46UI/mg pr.in str) , CAT (0,010±0,01UI/mg pr.in hipp and 0,005±0,004UI/mg pr.in str), GPx (0,01± 0,001nmol/mg pr.in both hippand str) and GST (23,73±1,68UI/mg pr.in hipp and 17,56± 1,04UI/mg pr.in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26μg/mlin str and 5,32 ± 1,08 μg/mlin hipp ) and Ca++( 2,26±0,06mmol/lin str and 2,32±0,07mmol/lin hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86ng/mg prin str and 14,8± 0,82ng/mg prin hipp), in the other hand the rates of caspase-9 were (278±14mAbs/mg pr.)in str and 212 ±24mAbs/mg pr.in hipp), caspase3 (184± 16mAbs/mg pr.)in str and 250 ±14mAbs/mg pr.in hipp), and BAX (0,926ng/mg prin str and 1,189ng/mg prin hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr.in str and 22,35± 1,77 nmol/min/mg pr.in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions whichwere prevented by bitter apricot kernels extract when associated with this pesticide.
Djellal D, Haddad S, Gasmi S, Chouit Z, Kebieche M, Hachemi M, HANFER M, Ferhat N, Bennoune O, Fetoui H, et al. CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.). The Journal of Microbiology, Biotechnology and Food Sciences [Internet]. 2022. Publisher's VersionAbstract
Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouringdownstream into food platesandcontributesto the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicityassessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performedin both brainareas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hippwith a values of 1,14 ± 0,04nmol/mg of proteins(pr)and 1,58 ± 0,09nmol/mg pr.respectively and a significant decrease in GSH(0,09 ± 0,01mmol/mg pr.in hipp and 0,08±0,01mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09UI/mg pr.in hipp14,54±1,46UI/mg pr.in str) , CAT (0,010±0,01UI/mg pr.in hipp and 0,005±0,004UI/mg pr.in str), GPx (0,01± 0,001nmol/mg pr.in both hippand str) and GST (23,73±1,68UI/mg pr.in hipp and 17,56± 1,04UI/mg pr.in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26μg/mlin str and 5,32 ± 1,08 μg/mlin hipp ) and Ca++( 2,26±0,06mmol/lin str and 2,32±0,07mmol/lin hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86ng/mg prin str and 14,8± 0,82ng/mg prin hipp), in the other hand the rates of caspase-9 were (278±14mAbs/mg pr.)in str and 212 ±24mAbs/mg pr.in hipp), caspase3 (184± 16mAbs/mg pr.)in str and 250 ±14mAbs/mg pr.in hipp), and BAX (0,926ng/mg prin str and 1,189ng/mg prin hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr.in str and 22,35± 1,77 nmol/min/mg pr.in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions whichwere prevented by bitter apricot kernels extract when associated with this pesticide.
Djellal D, Haddad S, Gasmi S, Chouit Z, Kebieche M, Hachemi M, HANFER M, Ferhat N, Bennoune O, Fetoui H, et al. CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.). The Journal of Microbiology, Biotechnology and Food Sciences [Internet]. 2022. Publisher's VersionAbstract
Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouringdownstream into food platesandcontributesto the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicityassessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performedin both brainareas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hippwith a values of 1,14 ± 0,04nmol/mg of proteins(pr)and 1,58 ± 0,09nmol/mg pr.respectively and a significant decrease in GSH(0,09 ± 0,01mmol/mg pr.in hipp and 0,08±0,01mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09UI/mg pr.in hipp14,54±1,46UI/mg pr.in str) , CAT (0,010±0,01UI/mg pr.in hipp and 0,005±0,004UI/mg pr.in str), GPx (0,01± 0,001nmol/mg pr.in both hippand str) and GST (23,73±1,68UI/mg pr.in hipp and 17,56± 1,04UI/mg pr.in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26μg/mlin str and 5,32 ± 1,08 μg/mlin hipp ) and Ca++( 2,26±0,06mmol/lin str and 2,32±0,07mmol/lin hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86ng/mg prin str and 14,8± 0,82ng/mg prin hipp), in the other hand the rates of caspase-9 were (278±14mAbs/mg pr.)in str and 212 ±24mAbs/mg pr.in hipp), caspase3 (184± 16mAbs/mg pr.)in str and 250 ±14mAbs/mg pr.in hipp), and BAX (0,926ng/mg prin str and 1,189ng/mg prin hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr.in str and 22,35± 1,77 nmol/min/mg pr.in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions whichwere prevented by bitter apricot kernels extract when associated with this pesticide.
Djellal D, Haddad S, Gasmi S, Chouit Z, Kebieche M, Hachemi M, HANFER M, Ferhat N, Bennoune O, Fetoui H, et al. CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.). The Journal of Microbiology, Biotechnology and Food Sciences [Internet]. 2022. Publisher's VersionAbstract
Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouringdownstream into food platesandcontributesto the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicityassessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performedin both brainareas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hippwith a values of 1,14 ± 0,04nmol/mg of proteins(pr)and 1,58 ± 0,09nmol/mg pr.respectively and a significant decrease in GSH(0,09 ± 0,01mmol/mg pr.in hipp and 0,08±0,01mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09UI/mg pr.in hipp14,54±1,46UI/mg pr.in str) , CAT (0,010±0,01UI/mg pr.in hipp and 0,005±0,004UI/mg pr.in str), GPx (0,01± 0,001nmol/mg pr.in both hippand str) and GST (23,73±1,68UI/mg pr.in hipp and 17,56± 1,04UI/mg pr.in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26μg/mlin str and 5,32 ± 1,08 μg/mlin hipp ) and Ca++( 2,26±0,06mmol/lin str and 2,32±0,07mmol/lin hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86ng/mg prin str and 14,8± 0,82ng/mg prin hipp), in the other hand the rates of caspase-9 were (278±14mAbs/mg pr.)in str and 212 ±24mAbs/mg pr.in hipp), caspase3 (184± 16mAbs/mg pr.)in str and 250 ±14mAbs/mg pr.in hipp), and BAX (0,926ng/mg prin str and 1,189ng/mg prin hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr.in str and 22,35± 1,77 nmol/min/mg pr.in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions whichwere prevented by bitter apricot kernels extract when associated with this pesticide.
Achi A, Demagh Y. Eulerian multiphase study of direct steam generation in parabolic trough with OpenFOAM. Heat Transfer [Internet]. 2022;52 (14). Publisher's VersionAbstract

Direct steam generation (DSG) in parabolic trough solar collectors is a feasible option for economic improvement in solar thermal power generation. Three-dimensional Eulerian two-fluid simulations are performed under OpenFOAM to study the turbulent flow in the evaporation section of the parabolic trough receiver and investigate the phase change, and pressure drop of water as a heat transfer fluid. First, the model's validity has been tested by comparing the numerical results of a laboratory scale boiler with the available correlations and semi-correlations of boiling flows from the literature. Simulations agreed well with Rouhani–Axelsson correlation for horizontal tubes, with a mean relative error of less than 7.1% for all studied cases. However, despite a mean relative error of less than 13.19% compared to the experimental data in the literature, the reported pressure drop factor remains valid; overprediction remains tolerable for most engineering applications. Second, the scaling effect on the mathematical model, from laboratory to commercial-scale configuration, was tested with experimental data of the DISS test loop in Platforma Solar de Almeria, Spain. The Monte Carlo Ray Tracing method under the Tonatiuh package allowed for obtaining the nonuniform heat flux distribution. Due to the large size of the evaporation section in the DISS loop (eight collectors), each collector is considered independently in the simulations. Thus, simulations follow each other, taking the numerical results of each collector output as input data in the next collector and so on until the last. The numerical results showed an excellent agreement for the void fraction with 3.53% against the Rouhani–Axelsson correlation. Frictional pressure losses are within a 17.06% error of the Friedel correlation, in the range of previous work in the literature, and the heat loss is less than 4.69% error versus experimental correlation.

Achi A, Demagh Y. Eulerian multiphase study of direct steam generation in parabolic trough with OpenFOAM. Heat Transfer [Internet]. 2022;52 (14). Publisher's VersionAbstract

Direct steam generation (DSG) in parabolic trough solar collectors is a feasible option for economic improvement in solar thermal power generation. Three-dimensional Eulerian two-fluid simulations are performed under OpenFOAM to study the turbulent flow in the evaporation section of the parabolic trough receiver and investigate the phase change, and pressure drop of water as a heat transfer fluid. First, the model's validity has been tested by comparing the numerical results of a laboratory scale boiler with the available correlations and semi-correlations of boiling flows from the literature. Simulations agreed well with Rouhani–Axelsson correlation for horizontal tubes, with a mean relative error of less than 7.1% for all studied cases. However, despite a mean relative error of less than 13.19% compared to the experimental data in the literature, the reported pressure drop factor remains valid; overprediction remains tolerable for most engineering applications. Second, the scaling effect on the mathematical model, from laboratory to commercial-scale configuration, was tested with experimental data of the DISS test loop in Platforma Solar de Almeria, Spain. The Monte Carlo Ray Tracing method under the Tonatiuh package allowed for obtaining the nonuniform heat flux distribution. Due to the large size of the evaporation section in the DISS loop (eight collectors), each collector is considered independently in the simulations. Thus, simulations follow each other, taking the numerical results of each collector output as input data in the next collector and so on until the last. The numerical results showed an excellent agreement for the void fraction with 3.53% against the Rouhani–Axelsson correlation. Frictional pressure losses are within a 17.06% error of the Friedel correlation, in the range of previous work in the literature, and the heat loss is less than 4.69% error versus experimental correlation.

Moumen L, Rebiai S-E. Exponential stability of the transmission wave equation with a distributed delay term in the boundary damping. Rendiconti del circolo matematico di palermo series 2 [Internet]. 2022;72 :3459–3486. Publisher's VersionAbstract

We consider a system of transmission of the wave equation with Neumann feedback control that contains a distributed delay term and that acts on the exterior boundary. We prove under some assumptions that the solutions decay exponentially in an appropriate energy space. To establish this result, we introduce a suitable energy function and use multipliers technique method and compactness-uniqueness argument.

Moumen L, Rebiai S-E. Exponential stability of the transmission wave equation with a distributed delay term in the boundary damping. Rendiconti del circolo matematico di palermo series 2 [Internet]. 2022;72 :3459–3486. Publisher's VersionAbstract

We consider a system of transmission of the wave equation with Neumann feedback control that contains a distributed delay term and that acts on the exterior boundary. We prove under some assumptions that the solutions decay exponentially in an appropriate energy space. To establish this result, we introduce a suitable energy function and use multipliers technique method and compactness-uniqueness argument.

Bensalem I, Benhizia A. Novel design of irregular closed-cell foams structures based on spherical particle inflation and evaluation of its compressive performance. Thin-Walled Structures [Internet]. 2022;181. Publisher's VersionAbstract

Due to the high degree of randomness in the microstructure of real closed-cell foams, many reported numerical models in the literature are not able to capture precisely the local morphological features found in solid foams geometry. This is still the main impediment that restricts the investigation of this novel material and motivates the development of a sophisticated 3D solid model, which describes properly the complex geometry of real closed-cell foams. In this regard, this paper presents an original approach to generate a realistic and accurate 3D computational model of irregular closed-cell foams with relative density control and detailed finite element analysis of their mechanical performance under quasi-static loading up to densification. The solid model is constructed based on spherical particles inflation simulation. It resembles the real foams in terms of local features such as cell walls irregularities and thickness variation. The modeling approach was successfully verified by comparing cell-morphological details of the generated models with those produced experimentally available in the literature and by the high-quality of obtained 3D printed models containing complex shapes and irregular cell wall thickness distribution. The evolution of spherical particles during the inflation process is analyzed based on finite element (FE) simulations. It was found that it can produce varying relative densities of foam due to the gradual decrease in the gap between the inflated particles, this makes the geometrical model of the foam suitable for studying the effect of local morphological characteristics on the mechanical performance of closed-cell foam material. To demonstrate that the compressive performance of the proposed closed-cell foam models can be controlled by relative density, 3D foam models were extracted from different inflation times and then subjected to quasi-static compression tests up to densification using the Abaqus software. The results confirm that the plateau stress can be expressed as a function of foam relative density, its accuracy is validated by comparing it to the closed-cell aluminum foam power law equation existing in the literature. The new design method offers suitable numerical models for AM technology, plenty of experimental works on closed-cell foam can be reduced for engineering applications.

Bensalem I, Benhizia A. Novel design of irregular closed-cell foams structures based on spherical particle inflation and evaluation of its compressive performance. Thin-Walled Structures [Internet]. 2022;181. Publisher's VersionAbstract

Due to the high degree of randomness in the microstructure of real closed-cell foams, many reported numerical models in the literature are not able to capture precisely the local morphological features found in solid foams geometry. This is still the main impediment that restricts the investigation of this novel material and motivates the development of a sophisticated 3D solid model, which describes properly the complex geometry of real closed-cell foams. In this regard, this paper presents an original approach to generate a realistic and accurate 3D computational model of irregular closed-cell foams with relative density control and detailed finite element analysis of their mechanical performance under quasi-static loading up to densification. The solid model is constructed based on spherical particles inflation simulation. It resembles the real foams in terms of local features such as cell walls irregularities and thickness variation. The modeling approach was successfully verified by comparing cell-morphological details of the generated models with those produced experimentally available in the literature and by the high-quality of obtained 3D printed models containing complex shapes and irregular cell wall thickness distribution. The evolution of spherical particles during the inflation process is analyzed based on finite element (FE) simulations. It was found that it can produce varying relative densities of foam due to the gradual decrease in the gap between the inflated particles, this makes the geometrical model of the foam suitable for studying the effect of local morphological characteristics on the mechanical performance of closed-cell foam material. To demonstrate that the compressive performance of the proposed closed-cell foam models can be controlled by relative density, 3D foam models were extracted from different inflation times and then subjected to quasi-static compression tests up to densification using the Abaqus software. The results confirm that the plateau stress can be expressed as a function of foam relative density, its accuracy is validated by comparing it to the closed-cell aluminum foam power law equation existing in the literature. The new design method offers suitable numerical models for AM technology, plenty of experimental works on closed-cell foam can be reduced for engineering applications.

YOUSFI H, Brioua M, Benbouta R. STUDY AND PREDICTION OF THE FATIGUE LIFE OF AISI 1045 STEEL STRUCTURES UNDER ROTATIONAL BENDING STRESSES. UPB scientific bulletin series d mechanical engineering [Internet]. 2022;84 (2). Publisher's VersionAbstract

Several difficulties and critical problems are facing the modern designers especially the unexpected damages. For such critical issues, the steel behavior’s investigation presents a significant point to predict fatigue life through avoiding sudden damage. An experimental study has been conducted to evaluate the AISI 1045 steel fatigue behavior using three specimens’ shapes: the first one is the conventional shape according to the ASTM E466-07 standard, the second one is performed in a notched shape, and the last specimen according to the pre-loading process. To complete the comparison among the three cases studied, a mandatory checking of the chemical compositions such as carbon content 0.45%, as well as the mechanical properties, have been investigated by preformed a tensile test in order to determine the maximum stress and the yield strength. The staircase method is employed to estimate and compare the endurance limit and its standard deviations for the three shapes. Moreover, and considered that the fatigue life expectancy of the AISI 1045 steel is a crucial step, the Stromeyer model has been proposed to predict the fatigue life which appears to be more effective, considering the average error for all cases compared to the experimental model.

YOUSFI H, Brioua M, Benbouta R. STUDY AND PREDICTION OF THE FATIGUE LIFE OF AISI 1045 STEEL STRUCTURES UNDER ROTATIONAL BENDING STRESSES. UPB scientific bulletin series d mechanical engineering [Internet]. 2022;84 (2). Publisher's VersionAbstract

Several difficulties and critical problems are facing the modern designers especially the unexpected damages. For such critical issues, the steel behavior’s investigation presents a significant point to predict fatigue life through avoiding sudden damage. An experimental study has been conducted to evaluate the AISI 1045 steel fatigue behavior using three specimens’ shapes: the first one is the conventional shape according to the ASTM E466-07 standard, the second one is performed in a notched shape, and the last specimen according to the pre-loading process. To complete the comparison among the three cases studied, a mandatory checking of the chemical compositions such as carbon content 0.45%, as well as the mechanical properties, have been investigated by preformed a tensile test in order to determine the maximum stress and the yield strength. The staircase method is employed to estimate and compare the endurance limit and its standard deviations for the three shapes. Moreover, and considered that the fatigue life expectancy of the AISI 1045 steel is a crucial step, the Stromeyer model has been proposed to predict the fatigue life which appears to be more effective, considering the average error for all cases compared to the experimental model.

YOUSFI H, Brioua M, Benbouta R. STUDY AND PREDICTION OF THE FATIGUE LIFE OF AISI 1045 STEEL STRUCTURES UNDER ROTATIONAL BENDING STRESSES. UPB scientific bulletin series d mechanical engineering [Internet]. 2022;84 (2). Publisher's VersionAbstract

Several difficulties and critical problems are facing the modern designers especially the unexpected damages. For such critical issues, the steel behavior’s investigation presents a significant point to predict fatigue life through avoiding sudden damage. An experimental study has been conducted to evaluate the AISI 1045 steel fatigue behavior using three specimens’ shapes: the first one is the conventional shape according to the ASTM E466-07 standard, the second one is performed in a notched shape, and the last specimen according to the pre-loading process. To complete the comparison among the three cases studied, a mandatory checking of the chemical compositions such as carbon content 0.45%, as well as the mechanical properties, have been investigated by preformed a tensile test in order to determine the maximum stress and the yield strength. The staircase method is employed to estimate and compare the endurance limit and its standard deviations for the three shapes. Moreover, and considered that the fatigue life expectancy of the AISI 1045 steel is a crucial step, the Stromeyer model has been proposed to predict the fatigue life which appears to be more effective, considering the average error for all cases compared to the experimental model.

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