Nickel oxide nanoparticles are formed by chemical precipitation and subsequent drying and calcinations at temperatures ≥523 K. Samples are characterized using X-ray diffraction and BET surface area measurements indicating the formation of a single NiO phase whose crystallite size increases with increasing calcination temperature. The electrical properties are examined by measuring DC and AC conductivities and dielectric properties as functions of temperature. Electrical conductivities first slightly increases with increasing particle size up to 7–10 nm and are about 8 orders of magnitude higher than that of NiO single crystals. Further increasing the particle size above 10 nm, leads to a monotonic decrease of conductivity. The data are discussed in view of variations of grain boundary as well as triple junction volume fractions as the particle size varies. At temperatures above θD/2 (θD is the Debye temperature), the conductivity is ascribed to a band-like conduction due to the large polaron. The activation energy of conduction was found to be minimal for the highly conducting samples of 7–10 nm, and gradually increases to ~0.5 eV with increasing the particle size above 10 nm. For T θD/2, the conductivity is best described by variable–range–hopping models. Model parameters are thus estimated and presented as functions of particle size. Frequency as well as temperature dependencies of the AC conductivity and dielectric constant exhibit trends usually observed in carrier dominated dielectrics.

Nickel oxide nanoparticles are formed by chemical precipitation and subsequent drying and calcinations at temperatures ≥523 K. Samples are characterized using X-ray diffraction and BET surface area measurements indicating the formation of a single NiO phase whose crystallite size increases with increasing calcination temperature. The electrical properties are examined by measuring DC and AC conductivities and dielectric properties as functions of temperature. Electrical conductivities first slightly increases with increasing particle size up to 7–10 nm and are about 8 orders of magnitude higher than that of NiO single crystals. Further increasing the particle size above 10 nm, leads to a monotonic decrease of conductivity. The data are discussed in view of variations of grain boundary as well as triple junction volume fractions as the particle size varies. At temperatures above θD/2 (θD is the Debye temperature), the conductivity is ascribed to a band-like conduction due to the large polaron. The activation energy of conduction was found to be minimal for the highly conducting samples of 7–10 nm, and gradually increases to ~0.5 eV with increasing the particle size above 10 nm. For T θD/2, the conductivity is best described by variable–range–hopping models. Model parameters are thus estimated and presented as functions of particle size. Frequency as well as temperature dependencies of the AC conductivity and dielectric constant exhibit trends usually observed in carrier dominated dielectrics.

Effect of acute exposure of male rats to estradiol valerate once a week for 3 weeks on the activity of phase I, phase II and lysosomal glycosidases has been studied. Treatment caused a significant reduction in both body and liver weight, however, the liver/body weight ratio was not changed. Phase I monooxygenases enzymes activities showed a significant decrease in the hydroxylation of benzo (a) pyrene, demethylation of methoxycoumarin, and deethylation of ethoxyresorufin. Phase II showed a significant increase in the glucuronidation of phenolphthalein, and a decrease in the glucuronidation of 4-methylumbellierone and p-nitrophenol.Also, estradiol treatment caused a significant elevation in the hepatic glycosidases activity.

Animal kingdom posseses numerous species that produce toxins. snakes and scorpion posseses the most diverse animal toxins in the animal kingdom. BPPs are pyroglutamyl proline rich in oligopolypeptides. BPP isolated from Bothrops jararaca venom were described in the middle of 1960 as a first natural inhibitors of the ACE. Among the 18 natural peptides whose sizes vary between 5 and 14 amino acids, the most potent is BPP 5a, and BPP 9a.Recently these peptides have been used as probes selective tools in the study of physiological possesses and in the development of therapeuic agents.Therefore, BPPs hold great promise in the future understanding and treatment of cardiovascular diseases.

The objective of this study was to determine the relationship of postpartum oxidative stress and the ovarian anoestrus in the dairy cows. The study concluded that excess free radical production with elevation of the cortisol hormone might play a role in the prolongation of the postpartum anoestrus in dairy cows. These may be due to exhaustion of antioxidant system in milk production, so it was advise supplementation the dam with antioxidants during the late stage of pregnancy and in postpartum period to stimulate the normal ovarian activity and cyclicity.

The objective of this study was to determine the relationship of postpartum oxidative stress and the ovarian anoestrus in the dairy cows. The study concluded that excess free radical production with elevation of the cortisol hormone might play a role in the prolongation of the postpartum anoestrus in dairy cows. These may be due to exhaustion of antioxidant system in milk production, so it was advise supplementation the dam with antioxidants during the late stage of pregnancy and in postpartum period to stimulate the normal ovarian activity and cyclicity.

The objective of this study was to determine the relationship of postpartum oxidative stress and the ovarian anoestrus in the dairy cows. The study concluded that excess free radical production with elevation of the cortisol hormone might play a role in the prolongation of the postpartum anoestrus in dairy cows. These may be due to exhaustion of antioxidant system in milk production, so it was advise supplementation the dam with antioxidants during the late stage of pregnancy and in postpartum period to stimulate the normal ovarian activity and cyclicity.

The use of chelating agents like DDTC and DTPA are useful in treatment of cadmium toxicity in rats. DDTC gave the best results.It is advisable to give this chelating agent as prophylactic during cadmium exposure.

The use of chelating agents like DDTC and DTPA are useful in treatment of cadmium toxicity in rats. DDTC gave the best results.It is advisable to give this chelating agent as prophylactic during cadmium exposure.

The use of chelating agents like DDTC and DTPA are useful in treatment of cadmium toxicity in rats. DDTC gave the best results.It is advisable to give this chelating agent as prophylactic during cadmium exposure.