Purpose of the Study: Egyptian agriculture suffers from many problems related to the use of available economic resources, the most important of which is lack of optimal utilization of resources, wasteful use of agricultural production inputs, reduced efficiency of irrigation water use, and the fertility of agricultural lands are deteriorating, in addition to increasing rates of encroachments on agricultural lands and shifting it from agricultural use to other non-agricultural uses, which limits the agricultural sector ability to achieve high growth rates, especially with the increasing global production of biofuels from crops that individuals consume as food, including wheat and corn, which constitutes an explicit threat to Egyptian food and national security. Objectives: The research aimed to: Estimate the changes in the sources and components of the total productivity of the factors for the main cereal crops in Egypt in the presence and absence of carbon dioxide emissions, Environmental impact assessment of changes in the productivity of these crops. Methods: The study applied analytical approaches to measure changes in productivity, as parameter analysis methods are used as methods of the aggregate production function, and non-parameterized methods of estimation, in addition to (Malmquist, 1953) which is one of the most important indicators of measurement changes in productivity and relies on a Data Envelopment Analysis (DEA) to measure efficiency and changes in TFP productivity and identify the sources of changes in productivity through changes in technical competence and technological change, as the two most important components of the change in total productivity. Results: Wheat Crop: Wheat crop by estimating the change in the different efficiencies of the wheat crop with co2 emissions, it was clear that a decrease in technological change (TC) during the study period, and thus a decrease in the average change in the total factor productivity (TFP), while without co2 emissions effect, the average change in the total factor productivity of (TFPc) indicates an increase in the actual wheat efficiency which is low due to the environmental impact of the emissions. Rice Crop: Rice crop by estimating the change in the different efficiencies of the rice crop with co2 emissions, it became clear that a decrease in the average technological change (TC), thus increasing the average change in the total factor productivity of the (TFP), whereas, without co2 emissions, it was found that the average change in the total factor productivity of the (TFPc) for the study areas was higher. Summer Maize Crop: It was clear that the average technological change (TC) for the summer maize crop with co2 emissions, decreased during the study period, and therefore a decrease in the average change in the total factor productivity of the (TFP), but without co2, an increase in the annual average of the change in technical efficiency (TEC), and a decrease in the average technological change (TC), i.e. in the use of technology, and an increase in the average change in the total factor productivity (TFPc).

Due to the complexity of the structure of the tooth periodontium, regeneration of the full tooth attachment is not a trivial task. There is also a gap in models that can represent human tooth attachment in vitro and in vivo. The aim of this study was to develop a bilayered in vitro construct that simulated the tooth periodontal ligament and attached alveolar bone, for the purpose of tissue regeneration and investigation of physiological and orthodontic loading. Two types of materials were used to develop this construct: sol-gel 60S10Mg derived scaffold, representing the hard tissue component of the periodontium, and commercially available Geistlich Bio-Gide® collagen membrane, representing the soft tissue component of the tooth attachment. Each scaffold was dynamically seeded with human periodontal ligament cells (HPDLCs). Scaffolds were either cultured separately, or combined in a bilayered construct, for 2 weeks. Characterisation of the individual scaffolds and the bilayered constructs included biological characterisation (cell viability, scanning electron microscopy to confirm cell attachment, gene expression of periodontium regeneration markers), and mechanical characterisation of scaffolds and constructs. HPDLCs enjoyed a biocompatible 3-dimensional environment within the bilayered construct components. There was no drop in cellular gene expression in the bilayered construct, compared to the separate scaffolds.

No abstract