Despite the important role that production function has played in growth literature, few attempts have been made to change the methodology to estimate it. The Cobb-Douglas functions are among the best known production functions utilized in applied production analysis. This paper describes development of a new model based on Cobb-Douglas production function with the used of robust method and partial least squares path modeling for parameter estimation. The new model attempted to solve two main problems in modeling namely the issue of multicollinearity and outliers. Each issue was handled separately but using the same method of least square for parameter estimations. This paper goes on to provide an overview of the measurements and structural criteria needed for model development and, also to introduce a robust partial least squares-path modeling for the Cobb-Douglas production function (RPLS-PM-CD). The researcher hypothesizes that utilization of the minimum covariance determinant (MCD) provides an estimate by the measurement model and expresses the structural relationships between the latent variables through the partial least squares-path modeling (PLS-PM).The inputs and outputs of the RPLS-PM-CD were based on agricultural wheat production data pertaining to AlKufra Agricultural Production Project. This paper is more theoretical and should be seen as a new way to estimate Cobb-Douglas production function.

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Introduction: Atherosclerosis is the major source of morbidity and mortality in the developed countries like Libya. Oxidative stress represents a risk factor and plays a key role at several steps of atherosclerosis. Formation of atherosclerotic plaques is the main reason for coronary artery disease. Aim: This study is aimed to assess the impact of the imbalance between body oxidants and antioxidants (oxidative stress) and its involvement in developing and severity of atherosclerosis in atherosclerotic with and without diabetes Libyan patients. Methods: The study sample comprised of atherosclerosis with and without diabetes patients (n = 73), as well as healthy controls (n = 27). Blood samples were collected to determine the levels of malonaldehyde (MDA) as oxidative biomarker, serum selenium level, total antioxidant status (TAS) level and some antioxidant enzymes including glutathione peroxidase (GPx), Catalase (Cat) and superoxide dismutase (SOD). Additionally, oxidant/antioxidant status was compared between atherosclerotic patients with and without diabetes in comparison to controls. Results: The results indicated a significant increase in MDA level among atherosclerotic patients compared to healthy subjects (P < 0.05). While the level of TAS, Cat, SOD and GPx was significantly decreased among patients compared to the controls (P < 0.05). For the atherosclerotic diabetic patients, the study was found a rise in the level of MDA as well as a marked decrease in TAS and the activity of tested antioxidant enzymes (P < 0.05). A good correlation was obtained between elevated MDA and decreased TAS, Cat, SOD and GPx. Conclusion: Determination of antioxidative defense markers contributes to understanding the effect of oxidative stress on the development and the prevention of cardiovascular disease.