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1.
Crude palm oil (CPO) is the richest natural source of carotenes that are destroyed in the conventional processing. There is a growing demand for nutritional products containing bioactive constituents externally fortified or preserved through modified process. A commercially viable process for the production of red palm olein (RPOn) rich in carotenes, tocols and sterols has been developed at pilot scale. The process developed involved neutralization of CPO followed by crystallization at controlled rate of cooling and deodorization of the resultant neutralized and winterized palm olein (WPOn) under controlled conditions of temperature and high vacuum. Analytical data related to micronutrients at each process step was monitored. The RPOn thus produced had not more than 0.25% of free fatty acids (FFA) and it retained more than 80% of the carotenes, about 85% of tocols and 65% of sterols originally present in the CPO. The physico-chemical characteristics of RPOn revealed that it is nutritionally of superior quality compared to that of the commercial refined bleached deodorized (RBD) palm olein currently available in the market. The carotenes, tocols and sterols profile of RPOn by HPLC showed that they were retained in their natural forms.  相似文献   
2.
Fida El Chami  Toni Sayah 《Calcolo》2010,47(3):169-192
In this paper we study the time dependent Stokes problem with some different boundary conditions. We establish a decoupled variational formulation into a system of velocity and a Poisson equation for the pressure. Hence, the velocity is approximated with curl conforming finite elements in space and Euler scheme in time and the pressure with standard continuous elements in space and Euler scheme in time. Finally, we establish optimal a priori and a posteriori estimates.  相似文献   
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The acute phase protein serum amyloid A (SAA), a marker of inflammation, induces expression of pro-inflammatory and pro-thrombotic mediators including ICAM-1, VCAM-1, IL-6, IL-8, MCP-1 and tissue factor (TF) in both monocytes/macrophages and endothelial cells, and induces endothelial dysfunction—a precursor to atherosclerosis. In this study, we determined the effect of pharmacological inhibition of known SAA receptors on pro-inflammatory and pro-thrombotic activities of SAA in human carotid artery endothelial cells (HCtAEC). HCtAEC were pre-treated with inhibitors of formyl peptide receptor-like-1 (FPRL-1), WRW4; receptor for advanced glycation-endproducts (RAGE), (endogenous secretory RAGE; esRAGE) and toll-like receptors-2/4 (TLR2/4) (OxPapC), before stimulation by added SAA. Inhibitor activity was also compared to high-density lipoprotein (HDL), a known inhibitor of SAA-induced effects on endothelial cells. SAA significantly increased gene expression of TF, NFκB and TNF and protein levels of TF and VEGF in HCtAEC. These effects were inhibited to variable extents by WRW4, esRAGE and OxPapC either alone or in combination, suggesting involvement of endothelial cell SAA receptors in pro-atherogenic gene expression. In contrast, HDL consistently showed the greatest inhibitory action, and often abrogated SAA-mediated responses. Increasing HDL levels relative to circulating free SAA may prevent SAA-mediated endothelial dysfunction and ameliorate atherogenesis.  相似文献   
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In the current study, Ni50Fe50 alloy powders were prepared using a high-energy planetary ball mill. The effects of TiC addition (0, 5, 10, 20, and 30 wt pct) and milling time on the sequence of alloy formation, the microstructure, and microhardness of the product were studied. The structure of solid solution phase, the lattice parameter, lattice strain, and grain size were identified by X-ray diffraction analysis. The correlation between the apparent densities and the milling time is explained by the morphologic evolution of the powder particles occurring during the high-energy milling process. The powder morphology was examined using scanning electron microscopy. It was found that FCC γ (Fe–Ni) solid solution was formed after 10 hours of milling, and this time was reduced to 7 hours when TiC was added. Therefore, brittle particles (TiC) accelerate the milling process by increasing crystal defects leading to a shorter diffusion path. Observations of polished cross section showed uniform distribution of the reinforcement particles. The apparent density increases with the increasing TiC content. It was also found that the higher TiC amount leads to larger lattice parameter, higher internal strain, and lower grain size of the alloy.  相似文献   
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An efficient pilot‐scale process was developed to produce nutraceutical products from fresh sea buckthorn (Hippophae rhamnoides) berries. Fresh berries were subjected to high‐pressure dewatering using a continuous screw press. The separated liquid phase containing 80–90% of pulp oil was clarified at 80 °C and centrifuged to obtain pulp oil, clear juice and sludge. The pulp oil yield was 2.7–2.8% of fresh berry weight with 66–70% extraction efficiency. The pulp oil was remarkably rich in carotenoids (2450–2810 mg kg?1), tocopherols (1409–1599 mg kg?1) and sterols (4096–4403 mg kg?1), with a characteristic fresh berry flavour and 16:1 as the major fatty acid (45.6–49.1%). The clear juice obtained was free from oil and contained high amounts of vitamin C (1683–1840 mg kg?1) and phytochemicals such as polyphenols (2392–2821 mg kg?1) and flavonoids (340–401 mg kg?1). Isorhamnetin (251–310 mg kg?1) was the major flavonoid in the juice, along with quercetin (77–81 mg kg?1) and kaempherol (12–16 mg kg?1). The juice was very acidic (pH 3), with high concentrations of organic acids (30.8–36.0 g kg?1). High‐performance liquid chromatography profiling of organic acids revealed quinic acid (18.1–19.9 g kg?1) as the major acid in the juice. The seeds in the pressed cake were separated and extracted for oil using supercritical CO2. Copyright © 2006 Society of Chemical Industry  相似文献   
8.
Since the Phoenicians inhabited the land of Canaan (the modern Lebanon), wine earned historical, cultural, social and economic dimensions in the life of its population. Through their trade network, evidence shows that the Phoenicians distributed wine, wine grapes and the winemaking technology that they had acquired from the east, throughout the Mediterranean region. However, the Lebanese wine sector did not take the required attention of the scientific community. Thus, this study gathers agri-food trade data, from national and international sources to analyse the Lebanese wine sector and evaluate its competitiveness in the international market using the revealed trade advantage and the revealed competitiveness indicators. Both indicators show that Lebanese wine has average competitiveness in the world market. This level of competitiveness can fluctuate depending on the political situation and the trade region and is highest for America and Asia. Finally, the study urges a long-term, general political framework that involves all stakeholders and policy-makers to work towards a sustainable Lebanese wine.  相似文献   
9.
The oil content and chemical composition of the volatiles from whole capsule, decorticated seed and husk of four varieties of cardamom viz. Malabar, Mysore, Vazhukka, and Guatemala were studied. The differences in the aroma of cardamom from different sources were attributed to the ratio of esters and 1,8-cineole in the oil. The main constituents of the oils were found to be terpinylacetate and 1,8-cineol. The study revealed that the oil obtained from a whole capsule of the Malabar variety was superior in quality compared to the oil from other varieties. The in vitro total antioxidant capacity of the oils from whole capsules by two different methods was also carried out, and it was found that the Malabar variety has the highest antioxidant activity compared to other varieties.  相似文献   
10.
The Lebanese coast is highly subject to seawater intrusion and groundwater deterioration. The study is carried out in Byblos district (Jbeil Caza) 35 km north of Beirut. It aims to investigate the seawater intrusion, to determine the regional water balance of the region and finally to estimate the economic value of that water for agricultural use. The monitoring of the aquifer was achieved through samples from different wells chosen randomly. As for the regional water balance, it was determined with use of a GIS model. The economic evaluation was carried out, using the contingent valuation method to estimate the willingness to pay of farmers to contribute to the improvement of groundwater quality; two alternative scenarios were proposed and compared with the current situation. The annual regional water balance is positive, which means that the region is rich in water. The monitoring results show that the coastal part of the region is slightly contaminated by seawater intrusion due to the excess of pumping from the aquifer. The economic evaluation estimated that farmers would contribute by 102 US$ yr − 1 for the first proposal and 166.67 US$ yr − 1 for the second.  相似文献   
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