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71.
Metabolic glycoengineering enables a directed modification of cell surfaces by introducing target molecules to surface proteins displaying new features. Biochemical pathways involving glycans differ in dependence on the cell type; therefore, this technique should be tailored for the best results. We characterized metabolic glycoengineering in telomerase-immortalized human mesenchymal stromal cells (hMSC-TERT) as a model for primary hMSC, to investigate its applicability in TERT-modified cell lines. The metabolic incorporation of N-azidoacetylmannosamine (Ac4ManNAz) and N-alkyneacetylmannosamine (Ac4ManNAl) into the glycocalyx as a first step in the glycoengineering process revealed no adverse effects on cell viability or gene expression, and the in vitro multipotency (osteogenic and adipogenic differentiation potential) was maintained under these adapted culture conditions. In the second step, glycoengineered cells were modified with fluorescent dyes using Cu-mediated click chemistry. In these analyses, the two mannose derivatives showed superior incorporation efficiencies compared to glucose and galactose isomers. In time-dependent experiments, the incorporation of Ac4ManNAz was detectable for up to six days while Ac4ManNAl-derived metabolites were absent after two days. Taken together, these findings demonstrate the successful metabolic glycoengineering of immortalized hMSC resulting in transient cell surface modifications, and thus present a useful model to address different scientific questions regarding glycosylation processes in skeletal precursors.  相似文献   
72.
The River Danube is with 2780 km the second longest river in Europe. Its catchment area covers 801 500 km2, with approximately 81 million inhabitants in 19 countries. River water for anthropogenic use, transportation and recreation is of major importance in all of these countries. Microbiological contamination from faecal pollution by anthropogenic sources is considered to be a crucial problem throughout the Danube River basin. Thus, detailed knowledge on the extent and the origin of microbial pollution is essential for watershed management. The determination of faecal indicator concentrations along the Danube and its major tributaries during two whole-river surveys and 16 permanent stations allowed for the first time to draw a clear picture of the faecal pollution patterns along the whole longitudinal profile of this important international river. By including a variety of environmental variables in statistical analysis, an integrative picture of faecal pollution in the Danube River basin could be evolved. Four hot spots and six stretches of differing faecal pollution were identified, mainly linked with input from large municipalities. Significant decline of microbiological pollution was observed in the upper and lower Danube stretches over the investigation period. In contrast, a significant increase in the middle part was evident. The planned implementation of new wastewater treatment plants and advanced wastewater treatment measures according to the European Union urban wastewater directive will have a great potential to reduce microbial faecal pollution in the Danube and thus improving water quality.  相似文献   
73.
Abstract: The role of different types of emulsifying salts—sodium citrate (TSC), sodium hexametaphosphate (SHMP), sodium tripolyphosphate (STPP) and tetrasodium pyrophosphate (TSPP)—on microstructure and rheology of “requeijão cremoso” processed cheese was determined. The cheeses manufactured with TSC, TSPP, and STPP behaved like concentrated solutions, while the cheese manufactured with SHMP exhibited weak gel behavior and the lowest values for the phase angle (G”/G’). This means that SHMP cheese had the protein network with the largest amount of molecular interactions, which can be explained by its highest degree of fat emulsification. Rotational viscometry indicated that all the spreadable cheeses behaved like pseudoplastic fluids. The cheeses made with SHMP and TSPP presented low values for the flow behavior index, meaning that viscosity was more dependent on shear rate. Regarding the consistency index, TSPP cheese showed the highest value, which could be attributed to the combined effect of its high pH and homogeneous fat particle size distribution.  相似文献   
74.
Inflammation and haemorrhage are the main characteristics of tissue injury in botropic envenomation. Although some studies have shown that anti-venom prevents systemic reactions, it is not efficient in preventing tissue injury at the site of the bite. Therefore, this work was undertaken to investigate the anti-inflammatory effects of the methanolic extract and fractions from D. elliptica and to evaluate the role of matrix metalloproteinases (MMPs) in this process. Effects of the extract and fractions from D. elliptica were evaluated using a carrageenan-induced paw oedema model in rats, and leukocyte rolling was visualized by intravital. The quantification of MMPs activities (MMP-2 and MMP-9) extracted from the dermis of mice treated with extract and fractions alone or incubated with venom was determined by zymographic analyses. Our results show that intraperitoneal (i.p.) injection of fractions significantly reduced paw oedema after the carrageenan challenge. Treatment with the tannins fraction also resulted in considerable inhibition of the rolling of leukocytes and this fraction was able to decrease the activation of MMP-9. These results confirmed the anti-inflammatory activity of the methanolic extract and tannins fraction of D. elliptica and showed that the dermonecrosis properties of B. jararaca venom might be mediated through the inhibition of MMP-9 activity.  相似文献   
75.
A method for solvent screening and searching for additives in the field of physical absorption processes is presented. A model based on the concept of virtual components and on the concept of a simplified abstract flow sheet is created. An estimation procedure for thermodynamically consistent property sets for the virtual component is developed. The model is implemented into MATLAB®. Its application is demonstrated in two studies including a study for a solvent additive. Potential candidates can be characterized and ranges for properties of the solvent or additive are found by means of the model. Conclusions obtained from the model support the screening process by a reduction of the number of further investigated components.  相似文献   
76.
The sludge generated by sewage treatment which meets regulatory standards can be used in agriculture. With this understanding, the focus of this study is the evaluation of the agricultural characteristics and inorganic substances in excess activated sludge, which was subjected to drying in a greenhouse. The variables (factor) evaluated during the drying process were: type of sludge (digested or not digested), addition of lime to the sludge, and the physical layout and rotation of sludge in the greenhouse. The parameters monitored for this assessment were moisture, volatile solids and pH. The greenhouse cover and sides were made of translucent plastic to allow the penetration of solar radiation and prevent water from entering. A impermeable floor was used. The sludge was generated in sewage treatment plants located in the metropolitan region of Grande Vitória, Espírito Santo, Brazil. The solar drying of wastewater sludge in a greenhouse presented satisfactory results.  相似文献   
77.
Near‐field plasmonic coupling and local field enhancement in metal nanoarchitectures, such as arrangements of nanoparticle clusters, have application in many technologies from medical diagnostics, solar cells, to sensors. Although nanoparticle‐based cluster assemblies have exhibited signal enhancements in surface‐enhanced Raman scattering (SERS) sensors, it is challenging to achieve high reproducibility in SERS response using low‐cost fabrication methods. Here an innovative method is developed for fabricating self‐organized clusters of metal nanoparticles on diblock copolymer thin films as SERS‐active structures. Monodisperse, colloidal gold nanoparticles are attached via a crosslinking reaction on self‐organized chemically functionalized poly(methyl methacrylate) domains on polystyrene‐block‐poly(methyl methacrylate) templates. Thereby nanoparticle clusters with sub‐10‐nanometer interparticle spacing are achieved. Varying the molar concentration of functional chemical groups and crosslinking agent during the assembly process is found to affect the agglomeration of Au nanoparticles into clusters. Samples with a high surface coverage of nanoparticle cluster assemblies yield relative enhancement factors on the order of 109 while simultaneously producing uniform signal enhancements in point‐to‐point measurements across each sample. High enhancement factors are associated with the narrow gap between nanoparticles assembled in clusters in full‐wave electromagnetic simulations. Reusability for small‐molecule detection is also demonstrated. Thus it is shown that the combination of high signal enhancement and reproducibility is achievable using a completely non‐lithographic fabrication process, thereby producing SERS substrates having high performance at low cost.  相似文献   
78.
The heart of palm is a food extracted from several species of palm trees. Only 10–20% of the raw material is transformed into canned hearts of palm, therefore this agro‐industry generates a large quantity of solid residue. The aim of this work was to extract and characterise a juice produced from this solid residue. This extract is compared with the traditional fruit juices (orange and pineapple juices), obtaining higher contents of minerals, such as magnesium (22.80 mg/100 g) and potassium (276.90 mg/100 g), phenolic compounds (gallic, 3,4‐dihydroxybenzoic, chlorogenic, syringic and caffeic acids) and high free radical scavenging capacity (expressed as 2,2‐diphenyl‐1‐picrylhydrazyl), which suggest high antioxidant activity. Additionally, a new soft drink was formulated using this king palm juice as its main ingredient. The soft drink samples formulated with this juice had high sensory acceptability and high intention of consumption, which suggests an important and low‐cost application for this industrial residue.  相似文献   
79.
The proportion of sustainable property in the total building stock remains small. One reason is that the financial added value resulting from sustainability is not sufficiently taken into account in property valuation due to the tendency of valuations to lag behind market trends. Quantitative information is provided to integrate those aspects of sustainability relating to value into valuations and thereby contribute to the reduction of valuation lag. The Centre for Corporate Responsibility and Sustainability (CCRS) Economic Sustainability Indicator (ESI) measures the risk of property to lose value and the opportunity to gain value due to future developments (e.g. climate change or rising energy prices). Five groups of value-related sustainability features were identified: flexibility and polyvalence; energy and water dependency; accessibility and mobility; security; and health and comfort. By minimizing the risk of loss in value through future developments, those sustainability features contribute to the property value. Their effects on property value were quantified by risk modelling. As an indicator for future-oriented property risk, the ESI is integrated into the discount rate of discounted cash flow valuations. The approach was tested for plausibility and practicability on more than 200 properties.

La proportion de biens immobiliers durables dans le parc immobilier total demeure faible. L'explication tient pour une part au fait que la valeur ajoutée financière résultant de la durabilité n'est pas suffisamment prise en compte dans l'évaluation des biens immobiliers en raison du fait que les évaluations tendent à avoir du retard sur les tendances du marché. Des informations quantitatives sont fournies afin d'intégrer les aspects de la durabilité liés à la valeur dans les évaluations et de contribuer ainsi à la réduction du retard dans les évaluations. L'Indicateur de Durabilité Economique (ESI) du Centre pour la Responsabilité et la Durabilité en Entreprise (CCRS) mesure le risque de perte de valeur des biens immobiliers et la possibilité d'en accroître la valeur du fait des évolutions futures (par ex. changement climatique et hausse des prix énergétiques). Cinq groupes de fonctions de durabilité liées à la valeur ont été identifiés: flexibilité et polyvalence, dépendance vis-à-vis de l'énergie et de l'eau; accessibilité et mobilité; sécurité; santé et confort. En minimisant le risque d'une perte de valeur causée par les évolutions futures, ces fonctions de durabilité contribuent à la valeur des biens immobiliers. Leurs effets sur la valeur des biens immobiliers ont été quantifiés par une modélisation des risques. En tant qu'indicateur du risque prospectif pour les biens immobiliers, l'ESI est intégré au taux d'actualisation des flux de trésorerie actualisés. Cette approche a été testée quant à sa plausibilité et sa praticabilité sur plus de 200 biens immobiliers.

Mots clés: flux de trésorerie actualisés, indicateur de durabilité économique, évaluation des biens immobiliers, modèle de risque, fonctions de durabilité, durabilité, bâtiments durables  相似文献   
80.
This work presents an extension of a previous proposed procedure [Costa, C.B.B., Wolf Maciel, M.R., Maciel Filho, R., 2005. Factorial design technique applied to genetic algorithm parameters in a batch cooling crystallization optimization. Computers and Chemical Engineering 29, 2229-2241] to be adopted as a prior analysis in optimization problems to be solved using genetic algorithm (GA). Chemical engineering problems are commonly highly non-linear and possess a large number of variables, sometimes with significant interactions among them. Such characteristics make the optimization problems really difficult to be solved by deterministic methods. GA is an increasing tool for solving this sort of problems. However, no systematic approach to establish the best set of GA parameters for any problem was found in the literature and a relatively easy to use and meaningful approach is proposed and proved to be of general application. The proposed approach consists of applying factorial design, a well-established statistical technique to identify the most meaningful information about the influences of factors on a specific problem, as a support tool to identify the GA parameters with significant effect on the optimization problem. This approach is very useful in conducting further optimization works, since it discharges GA parameters that are not statistically significant for the evolutionary search for the optimum, saving time and computation burden in evolutionary optimization studies.  相似文献   
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