Sample size determination is an essential task in research designs for the accuracy of estimation about the population is mainly depends on the sample size. The problem motivating this topic is to answer the question arises when designing a study:\" how large a sample must be?\". Sample size estimation is an essential step in statistical study plan where an estimate of error variance and specification of effect size is essential for power analysis and sample size determination , because without determination of optimum sample size , the research or experiment will lack the precision or time and resources will be wasted .This paper discusses the issue of successful sample size determination. Some related terms such as confidence intervals and power analysis were outlined , and illustrations based on theoretical data would be carried and concluding results would be given on the basis of the study.

It is the concern of traffic engineering to handle the issue of and find solutions for transportation problems that are increasing in direct proportion with the population growth. Correct planning of transportation by traffic engineers affects the interaction among drivers and delay times of travelling vehicles. In this study, a research was carried out for vehicles’ headways at signalized arterials on lane by lane basis taking into consideration the behavioural attitudes of drivers. \nDuring the study intervehicular dependence was investigated and free vehicle ratio relations were developed correspondingly for each lane. Analyses were made for the purpose of inspecting how the free vehicle ratio is changed as vehicles moved away from the upstream intersection and approached to the downstream intersection. In the analysis the effect of upstream intersection’ green time to the cycle time (g/Cupstream) and approached to the downstream intersection’ green time to the cycle time (g/Cdownstream) on vehicle movement are shown. Further more delay at signalized intersections according to the vehicle arrivals were calculated on the basis of determined free vehicle ratio relations and compared lane by lane basis.

Excessive use of atrazine- a herbicide has raised severe concerns due to its toxicity in plants, soil, and water bodies. Various strategies have been applied to diminish the intoxication of pesticides in humans. The present study was planned to investigate the possible protective action of melatonin and vitamin E & C against atrazine-induced nephrotoxicity. Animals were randomly separated into eight groups: Control; Vitamin E (50mg/kgbw); Vitamin C (200mg/kgbw); Melatonin (MEL) (10mg/kgbw); Atrazine (ATZ) (300mg/kgbw); ATZ+ Vit. E; ATZ+ Vit. C; and ATZ+MEL groups and treated orally, daily for 28 days. The in vivo administration of atrazine demonstrated a significant decrease in their body weight. Atrazine-induced nephrotoxicity influenced the oxidative damage exhibited by enhanced LPO, reduced GSH and antioxidant capacity; altered antioxidant enzymes (CAT, SOD, GPx, and GST) and DNA damage. Histopathological findings of the kidneys revealed disturbed architectural integrity characterized by infiltration, swelling, and degeneration of renal tubules in atrazine intoxicated rats. Interestingly, atrazine-induced oxidative damage and histopathological and biochemical alterations in the kidneys were attenuated by co-administration of melatonin and vitamin E&C. We suggest the predominant action of melatonin than vitamin E&C. In conclusion, melatonin emerged as a stronger and more efficient nephroprotective antioxidant as compared to vitamin E&C against the cellular damage induced by atrazine intoxication in rats.

The threat of increased industrial accidents and terrorist activities demands protection of structure against blast loading. The pressure-impulse (P-I) diagrams also called iso-damage diagrams indicates damage level in a structure. In the present investigation, P-I diagrams for sandwich panel with steel face and back-sheets and paper honeycomb core are developed. The numerical approach is used to get series of pressure and impulse points for particular damage level. The damage criteria considered in present study is maximum back sheet deflection. However, core crushing is limited to 5 mm in this investigation for the uniformity of the analysis. Sandwich panel with paper honeycomb core is modelled in ABAQUS/Explicit® and blast load is applied for range of loading i.e. impulsive, dynamic and quasi-static using CONWEP formulation. Based on the analysis performed, P-I diagrams are developed for damage levels of 1%, 1.5%, 2%, 2.5% and 3%.

Introduction: Hammada elegans Botsch (Chenopodiaceae) a xerophytic plant popularly known as (Ajram) is widely spread perennial shrub in the steep area of Algeria (Laghouat); it is considered a promising species traditionally used to treat inflammation mellitus. Therefore, the present study aimed to evaluate for the first time the in vivo anti-inflammatory, anti-diabetic and acute toxicity properties of acetonic, methanolic and aqueous Hammada elegans Botsch extracts. \nMethods: The acute toxicity was carried out according to the method described by OECD by using increasing single doses (50-1500 mg/kg bw). The in vivo anti-inflammatory effect is investigated in Wistar rats by using the test of the rat paw edema induced by injection of a carrageenan solution. The antidiabetic activity was evaluated in vivo using three tests: short-term test (in non-diabetic rats), starch-induced hyperglycemia test (in non-diabetic rats) and long-term alloxan test (experimental diabetes). \nResults: The acute toxicity study shows no deaths in rats and no clinical signs of toxicity after administration of increasing doses of the extracts (50-1500 mg/kg body weight (bw)). The anti-inflammatory effects show that all extracts significantly inhibit rat paw edema (EC50less than 345.51± 0.29mg/Kg).Therefore, the acetonic extract (EC50 = 157.45± 0.33 mg/Kg) had the more active anti-inflammatory activity than that of the standard inhibitor “Ibuprofen”. In addition, the evaluation of the anti-diabetic activities by three tests shows that: in the short-term test there is no significant decrease in blood sugar in normal rats, whereas in starch-induced hyperglycemia test the aqueous extract was significantly decreases hyperglycemia (57.21 ±1.2 4mg AEAC/kg bw) when compared to all tested extracts, while in the long-term test the acetonic extract was significantly decreases hyperglycemia (9.18 ± 0.72 mg GEAC/kg bw) when compared to all tested extracts. \nConclusions: Hammada elegans extracts seem to have potential therapeutic possibilities for the prevention and treatment of the inflammatory and diabetic effects.

This research examines the influence of age on healthy child nasal airflow along the entire nasal cavity. In this research, a nasal airflow simulation is performed on a Malaysian 5-years-old female child via computational fluid dynamics (CFD). The Malaysia female child model exhibits narrower and thinner nasal passageway and has shorter turbinates region as compared with the other two models, i.e., male child model and female adult model from previous works. Despite their differences, a general trend is still visible in terms of cross-sectional area and average velocity magnitude profiles of the airways along with the axial distance. Besides, pressure drop, which is also known as the breathing resistance, was found to decrease as the age increases. It is also worth noticing that the flow field in the nasal cavity of a child tends to concentrate centrally when the airstream develops.