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91.
Effect of inulin on texture and clarity of gellan gels   总被引:1,自引:0,他引:1  
The effect of inulin on the gelation of 0.5 wt% low acyl gellan in the presence of increasing concentrations of potassium chloride was investigated by large deformation compression experiments and visible light absorbance. The sugar and salt concentrations varied from 0 to 15 wt% and 40-100 mM, respectively. Stress and strain at failure along with Young’s modulus were calculated from each compression curve. Samples prior to compression were refrigerated at 5 °C for 24 h. Reduced gel strength and firmness were observed for all inulin and salt concentrations. Increasing amounts of inulin resulted in an increase in gel strength which was greater for higher potassium concentrations. Elasticity values did not exhibit great diversion. Inulin at concentrations of 5 and 10 wt% led to less turbid gels than those with only gellan. Samples containing 15 wt% inulin gave absorbance readings greater than 1.  相似文献   
92.
The antioxidant and antimicrobial activity of four Thymus species (boissieri, longicaulis, leucospermus, and ocheus) extracts were determined. Two methods (Rancimat and malondialdehyde by high-performance liquid chromatography) were used to measure the antioxidant action in comparison with common commercial antioxidants, including butylated hydroxytoluene and alpha-tocopherol. The extracts that presented high antioxidant activity were encapsulated in liposomes and their antioxidant action was again estimated. Thermal-oxidative decomposition of the samples (pure liposomes and encapsulating extracts) was studied using the differential scanning calorimetry method. The modification of the main transition temperature for the lipid mixture and the splitting of the calorimetric peak in the presence of the antioxidants were also demonstrated by differential scanning calorimetry. All extracts showed antioxidant and antimicrobial activities. Some extracts showed superior or equal antioxidant activity to alpha-tocopherol. When the extracts were encapsulated in liposomes, their antioxidant as well as antimicrobial activities proved to be superior from the same extracts in pure form.  相似文献   
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Historically, honey has been important in Greek culture. The chemical composition and the potential of Greek honey extracts (thyme, pine and fir honey) to influence the oestrogenic activity and the cell viability of breast (MCF-7), endometrial (Ishikawa) and prostate (PC-3) cancer cells were investigated. All honeys contained total phenolics, phenolic acids and hydroxymethylfurfural, the levels being highest in thyme honey. Sugars and volatile compounds, but not fatty acids, were detected in all honey extracts. Thyme, pine and fir honey showed both antioestrogenic and a weak oestrogenic effect at low and high concentration, respectively, in MCF-7 cells. Thyme honey reduced the viability of Ishikawa and PC-3 cells, whereas fir honey stimulated the viability of MCF-7 cells. In conclusion, Greek honeys are rich in phenolic compounds, they modulate oestrogenic activity whereas a thyme honey-enriched diet may prevent cancer-related processes in breast, prostate and endometrial cancer cells.  相似文献   
96.
Recently, social networks have become the most prevalent IT paradigm, as the vast majority of Internet users maintain one or multiple social networking accounts. These accounts, irrespectively of the underlying service, contain rich information and data for the owner’s preferences, social skills, everyday activities, beliefs and interests. Along with these services, the computation, sensing and networking capabilities of the state of the art mobile and portable devices, with their always-on mode, assist users in their everyday lives. Thus, the integration of social networking services with current pervasive computing systems could provide the users with the potential to interact with other users that have similar interests, preferences and expectations; and in general, the same or similar context, for limited or not time periods, in order to ameliorate their overall experience, communicate, socialise and improve their everyday activities with minimal effort. This paper introduces a cross-community context management framework that is suitable for Cooperating Smart Spaces, which couple the advantages of pervasive computing and social networking. This framework goes beyond the state of the art, among others, in that cross-community context from a multitude of sources is collected and processed to enhance the end user experience and increase the perceived value of the services provided.  相似文献   
97.
In this work, we used time-resolved imaging to study the dynamics of the laser-induced forward transfer (LIFT) process of a silver nanoparticle (NP) ink (NP size: 30–50 nm). LIFT is a versatile direct write technique in which a variety of functional materials can be transferred from a donor substrate to a receiving substrate with high spatial resolution. Two different LIFT configurations were employed: (a) dynamic release layer (DRL)-assisted LIFT, in which direct expose of the silver NP ink to laser irradiation is prevented, and (b) DRL-free LIFT, in which the silver NP ink is exposed to laser irradiation. Jetting dynamic behavior, initiated by a cavitation bubble generation and expansion, was observed in both LIFT configurations. However, jetting dynamics were significantly milder in the case of DRL-assisted LIFT, resulting in a wide laser fluence processing window (100–230 mJ/cm2) for high uniformity and reproducibility printing of silver NP ink droplets. On the contrary, DRL-free LIFT resulted in smooth jetting dynamics only for a narrow laser fluence window (30–40 mJ/cm2). The explanation of the different dynamics is based on the different mechanisms that govern the conversion of the laser pulse energy to a dynamic cavitation bubble for each LIFT configuration, i.e., (a) heat diffusion, mediated by the DRL layer, in DRL-assisted LIFT and (b) microcavitation around the silver NPs due to near field enhancement when no DRL is used. In addition, the mechanism of formation of undesirable satellite droplets around the main deposited droplets was studied by using a flexible polymeric receiving substrate. The importance of the smooth jetting behavior, achieved by DRL-assisted LIFT, was highlighted for high-resolution printing of silver NP ink as well as for ensuring enhanced LIFT processing stability.  相似文献   
98.
Despite widespread proliferation of mobile devices providing access to a variety of advanced and data-rich services, adoption of those services remains low in most of the Western world. Thus, research related to the acceptance and use of mobile technology and services continues to develop. Traditional research in this domain has been useful for exploring adoption and use related to individual technologies or novel services. However, our research efforts indicate that users often reflect on former experiences with similar technologies or services when choosing mobile services. This suggests that when exploring mobile service usage decisions, focus cannot be placed on mobile services alone. Through two longitudinal field studies conducted in Denmark during 2004 and 2005, this article further explores the manner in which users' choices of mobile services are influenced by their reference situations and reference prices. The article suggests that users cognitive referencing is an influential factor that must be considered when exploring their usage behaviour in the mobile services market.  相似文献   
99.
Human error can have potentially devastating consequences in contexts such as healthcare, but there is a rarely a simple dichotomy between errors and correct behaviour. Furthermore, there has been little consideration of how the activities of users (erroneous and otherwise) relate to the conceptual fit between user and device, despite the fact that healthcare technologies are becoming increasingly prevalent and complex. In this article, we present a study in which nurses’ conceptions of infusion device practice were elicited to identify misfits. By focusing on key concepts that users work with when setting up infusions and the extent to which the system supports them, our analysis highlights how actions are influenced by the different resources available to users including: the device itself; supporting artefacts; the conceptual understanding of the user; and the community of practice the user is part of. The findings reveal the ways in which users are resourceful in their day-to-day activities and also suggest potential vulnerabilities within the wider system that could threaten patient safety. Our approach is able to make previously under-explored aspects of practice visible, thus enabling insight into how users act and why.  相似文献   
100.
Background: Carfilzomib is a first-line proteasome inhibitor indicated for relapsed/refractory multiple myeloma (MM), with its clinical use being hampered by cardiotoxic phenomena. We have previously established a translational model of carfilzomib cardiotoxicity in young adult mice, in which metformin emerged as a prophylactic therapy. Considering that MM is an elderly disease and that age is an independent risk factor for cardiotoxicity, herein, we sought to validate carfilzomib’s cardiotoxicity in an in vivo model of aging. Methods: Aged mice underwent the translational two- and four-dose protocols without and with metformin. Mice underwent echocardiography and were subsequently sacrificed for molecular analyses in the blood and cardiac tissue. Results: Carfilzomib decreased proteasomal activity both in PBMCs and myocardium in both protocols. Carfilzomib induced mild cardiotoxicity after two doses and more pronounced cardiomyopathy in the four-dose protocol, while metformin maintained cardiac function. Carfilzomib led to an increased Bip expression and decreased AMPKα phosphorylation, while metformin coadministration partially decreased Bip expression and induced AMPKα phosphorylation, leading to enhanced myocardial LC3B-dependent autophagy. Conclusion: Carfilzomib induced cardiotoxicity in aged mice, an effect significantly reversed by metformin. The latter possesses translational importance as it further supports the clinical use of metformin as a potent prophylactic therapy.  相似文献   
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