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161.
Information Retrieval Journal - Ranking models are the main components of information retrieval systems. Several approaches to ranking are based on traditional machine learning algorithms using a... 相似文献
162.
Azza M. Mohamed Mohga S. Abdalla Maha Z. Rizk El-Sayed M. E. Mahdy Abdel-Razik H. Farrag Fatma S. El-Sharabasy Hanan F. Aly Mohamed R. Mohamed 《Indian journal of clinical biochemistry : IJCB》2014,29(4):418-429
Anabasis articulata (Forssk) Moq. (Chenopodiaceae) is an herb, grows in Egypt, and used in folk medicine to treat diabetes, fever, and kidney infections. The protective and therapeutic effects of the ethanol extract of A. articulata aerial parts were evaluated against dimethylnitrosamine (DMN)-induced liver fibrosis, compared with the standard drug, silymarin. Hepatic hydroxyproline content, serum transforming growth factor-β1 (TGF-β1), interleukin 10 (IL-10) and fructosamine were measured as liver fibrosis markers. Hepatic malondialdehyde (MDA), nitric oxide (NO), catalase (CAT), glutathione reductase (GR) and glutathione content (GSH) were measured as oxidant/antioxidant markers. Parallel histopathological investigations were also performed. Protective and therapeutic administration of A. articulata (100 mg/kg daily for 4 weeks), markedly prevented DMN-induced loss in body and liver weights. The extract significantly inhibited the elevation of hepatic hydroxyproline, NO and MDA (P < 0.05), as well as serum fructosamine, and TGF-β1 (P < 0.05) induced by DMN while it restored IL-10 to normal level in both protective and therapeutic groups. Furthermore, A. articulata prevented the depletion in CAT, GR, and GSH levels (P ≤ 0.05). In addition, oral administration of A. articulata extract and silymarin to both protective and therapeutic groups reduced the increase in liver function enzyme activities; alanine and aspartate amintransferases, gamma-glutamyl transferase in addition to alkaline phosphatase, and caused significant increase in serum albumin concentration as compared to DMN group. These data corresponded closely with those obtained for the drug silymarin. Histopathological studies confirmed the biochemical data and revealed remarkable improvement in liver architecture. Thus, it could be concluded that, A. articulata extract exhibited in vivo hepatoprotective and therapeutic effects against DMN-induced liver injury and may act as a useful agent in controlling the progression of hepatic fibrosis through reduction of oxidative stress and improving liver function. 相似文献
163.
This study predicts the impact of technological, organizational and environmental (TOE) determinants on e-maintenance technology readiness in manufacturing firms. Survey responses of 308 managers from a wide spectrum of manufacturing firms have been validated and analyzed by means of structural equation modelling. The findings indicate that dimensions of e-maintenance technology readiness in manufacturing firms are mainly influenced by technological and organizational determinants involving technological infrastructure and competence, expected benefits and challenges of e-maintenance, and firm size and ownership. Surprisingly, there is no significant effect of competitive pressures on e-maintenance readiness. This study offers managers and vendors a frame of reference to analyze firm's situation before initiating new innovations. In case of e-maintenance technology, adoption strategies should be built around fostering level of employees’ technological knowledge and skills, technology infrastructure as well as sustaining potential benefits and encountering potential challenges associated with e-maintenance technology. This paper is one of the early studies that predict dimensions of technology readiness index (TRI) through the determinants of technology–organization–environment (TOE) framework. Also, it is among the first attempts to link prominent technology adoption models to e-maintenance technology as a novel form of enterprise innovations. 相似文献
164.
This paper presents a simple-to-construct, low dead volume pump capable of generating a wide range of positive and negative pressures for microfluidic applications. The pump generates pressure or vacuum by changing the volume of air confined inside a syringe and is able to generate pressures between -95 and +300 kPa with a resolution as high as 1 Pa. Different from syringe pumps and electrokinetic pumping, which are capable of controlling flow rates only, our pump can be used to generate constant flow rates or constant pressures, which are required for certain applications such as the aspiration of biological cells for biophysical characterization. Compared to syringe pumps, the new pump has almost zero dead volume and does not exhibit pulsatile flows. Additionally, the system does not require electrical power and is cost effective (~$100). To demonstrate the capabilities of the pump, we used it to aspirate osteoblasts (MC3T3-E1 cells) and to determine Young's modulus of the cells, to generate a concentration gradient, and to produce variable-sized droplets in microchannels using hydrodynamic focusing. 相似文献
165.
Mohamed Hashim Mohamed Ashmel Tlemsani Issam Matthews Robin 《Education and Information Technologies》2022,27(3):3171-3195
Education and Information Technologies - Digital transformation in the global higher education industry determines the future roadmap to a sustainable education management strategy. This research... 相似文献