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1.
In recent years, there has been rapid expansion of glycan synthesis, fueled by the recognition that the structural complexity of sugars translates to a myriad of biological functions. Such chemical syntheses involve many challenges, mostly due to the regio- and stereochemical aspects of glycosidic bond formation. One-pot strategies were developed to assist in attaining faster and more economical access to the glycan constructs. In this front, achievements in protecting group manipulation, glycosylation, and combinations of these have been reported. Protecting group manipulations in one pot take advantage of the reaction compatibility of commonly used transformations, many of which occur in high regioselectivity. Sequential glycosylations, on the other hand, rely on leaving group orthogonalities and reactivity tuning, as well as the preactivation technique. Altogether, these approaches offer attractive means to the much needed glycan structures and, consequently, help usher in advances in glycoscience.  相似文献   
2.
A Multidisciplinary Research Programme (MRP) is being developed since 1989 in the Universidad Complutense de Madrid (UCM), Spain, to support cross-disciplinary research projects. This paper analyses the incidence of interdisciplinarity in the UCM scientific publications over the period 1990–96 and tries to determine the success of the Programme at fostering cross-disciplinary research. Interdisciplinary in the UCM is measured through the collaboration of authors from different institutional addresses within the UCM, both in scientific publications and in research projects. Publications jointly signed by the different teams that collaborate in the projects were identified as an indicator of the success of the Programme in integrating disciplines. Interdisciplinary collaboration within the UCM showed an upward trend over time. Publications of MRP groups showed a higher interdisciplinary collaboration rate than the rest of the UCM (17% vs. 9%). Dramatic repercussions of the Programme were not expected due to its limited magnitude, but it worked as a catalyst, enhancing interdisciplinary relations within the UCM. The interest of such a programme is supported by its effects, both direct effects on granted teams and indirect on the whole UCM community.  相似文献   
3.
High‐intensity pulsed electric fields (HIPEF) is an emerging non‐thermal food preservation technology which has the potential to pasteurize pumpable liquid foods. Its application is being studied to evaluate it as potential alternative or complementary process to thermal pasteurization. Orange juice‐milk beverage with added bioactive components is a ready‐to‐drink beverage developed as an alternative to traditional soft drinks. In the present work, two HIPEF treatments (35 and 40 kV/cm) and six different treatment times (from 40 to 180 µs) were evaluated to assess their effect on the fatty acid profile of an orange juice‐milk beverage fortified with n‐3 fatty acids and oleic acid. The effect of HIPEF treatment on various physicochemical properties of the beverages: pH, °Brix, hydroxymethylfurfural or peroxide index was also determined. After HIPEF treatment, non‐significant changes in the contents of saturated fatty acids, monounsaturated fatty acids or polyunsaturated fatty acids were observed. Neither peroxides nor intolerable levels of furfurals were detected. Only a small reduction in fat content (p <0.05) was found. In conclusion, HIPEF can be proposed as an alternative preservation technology due to these minimal changes which are negligible from the nutritional point of view.  相似文献   
4.
Many circulating cancer-related proteins, such as fibroblast growth factors (FGFs), associate with glycosaminoglycans—particularly heparan sulfate—at the cell surface. Disaccharide analogues of heparan sulfate had previously been identified as the shortest components out of the sugars that bind to FGF-1 and FGF-2. Taking note of the typical pose of l -iduronic acid, we conceived of per-O-sulfonated analogues of such disaccharides, and devised a single-step procedure for per-O-sulfonation of unprotected sugars with concomitant 1,6-anhydro bridge formation to achieve such compounds through direct use of SO3 ⋅ Et3N as sulfonation reagent and dimethylformamide as solvent. The synthesized sugars based on the oligomaltose backbone bound FGF-1 and FGF-2 mostly at the sub-micromolar level, although the tetrasaccharide analogue achieved low-nanomolar binding with FGF-2.  相似文献   
5.
When structural damage appears in architecture, as in civil engineering, one of the first things to do is to analyse the level of stresses supported by the structural elements of the building. In most of the cases, the deduction of these stresses is carried out by means of one verification of the "design loads", using analytic methods based (or not) on standardised computer assisted applications. Nowadays, there is not one experimental method close enough to deduce the loads really supported by the structural elements. This article deals precisely about the resolution of this problem by means of the hole drilling technique applied on stone constructions as this is very common in architectural heritage. The particular use of the hole drilling technique in architectural heritage is named Donostia method by the authors, and allows both the deduction of the principal stress values and their directions. This is a very important aspect when the structural damages are generated by anomalous loads.  相似文献   
6.
Carbon fiber sheet molding compounds (C-SMCs) are discontinuous fiber reinforced composite materials. Among them, epoxy-based C-SMCs are becoming relevant materials due to their high thermomechanical performance and better formability than continuous fiber reinforced composites. The thermomechanical performance of epoxy resins and epoxy based continuous carbon fiber composites have shown to be influenced by hygrothermal aging. In this work, this influence is studied for an epoxy-based C-SMC. Epoxy-based C-SMC samples were hygrothermally aged by means of accelerated conditioning, exposing them to 65% relative humidity, and 80°C in a climatic chamber. The equilibrium moisture content, as well as the moisture diffusion coefficient has been determined. The thermomechanical properties of epoxy C-SMC have been analyzed by dynamic mechanical analysis, tensile, 3-point bending, and short beam tests in dry and aged samples. The results showed that epoxy C-SMC is affected by hygrothermal aging in the cases of moisture intake and its effects on Tg value, but interestingly, the hygrothermal aging did not generate any degradation effects in the mechanical response of epoxy C-SMC.  相似文献   
7.
8.
The total antioxidant capacity (hydrophilic plus lipophilic) of sixteen different commercial samples of pasteurized and ultra high temperature (UHT) treated milk was determined using the oxygen radical absorbance capacity assay using fluorescein as a fluorescent probe. A significant correlation between the percentage of fat and the value of the total antioxidant capacity was found in milk samples obtained from the same batch of raw milk. Analyses of the whole milk, whey and deproteinized milk showed that the major contributor to the total antioxidant capacity of whole milk was the casein fractions, while albumin was the major contributor to the total antioxidant capacity of whey protein. Hydrophilic antioxidant compounds, such as vitamin C and uric acid, were the main contributors to the total antioxidant capacity of the deproteinized milk. Significant differences in total antioxidant capacities were found between whey and deproteinized samples obtained from pasteurized and UHT-treated milk, the values being higher for the former.  相似文献   
9.
The deep insight into the different elements that compose photovoltaic (PV) systems is capital to boost the optimization of each one of them and consequently, increment of the overall performance of the whole PV systems. In this paper we address the open problem of obtaining empirical accurate models of monocrystalline PV modules in a systematic and unattended fashion. In order to tackle this issue, we used a dual model oriented modeling approach based on artificial neural networks (ANN) due to their advantages, being the generalization capability the most outstanding one. We tried two different model approaches with different input/outputs specifications to learn the electrical behavior of a monocrystalline PV module Atersa A-55 placed on the roof of the Faculty of Engineering of Vitoria-Gasteiz (Basque Country University, Spain). Following these approaches we found two season oriented models of IPV with a RMSE accuracy of 0.20 mA and 0.26 mA respectively, which is better than the precision of the measurement devices. After comparing these results with the state-of-art ones, we conclude that we have outperformed the previously existing results.  相似文献   
10.
Moyamoya arteriopathy (MA) is a rare cerebrovascular disorder characterized by ischemic/hemorrhagic strokes. The pathophysiology is unknown. A deregulation of vasculogenic/angiogenic/inflammatory pathways has been hypothesized as a possible pathophysiological mechanism. Since lipids are implicated in modulating neo-vascularization/angiogenesis and inflammation, their deregulation is potentially involved in MA. Our aim is to evaluate angiogenic/vasculogenic/inflammatory proteins and lipid profile in plasma of MA patients and control subjects (healthy donors HD or subjects with atherosclerotic cerebrovascular disease ACVD). Angiogenic and inflammatory protein levels were measured by ELISA and a complete lipidomic analysis was performed on plasma by mass spectrometry. ELISA showed a significant decrease for MMP-9 released in plasma of MA. The untargeted lipidomic analysis showed a cumulative depletion of lipid asset in plasma of MA as compared to HD. Specifically, a decrease in membrane complex glycosphingolipids peripherally circulating in MA plasma with respect to HD was observed, likely suggestive of cerebral cellular recruitment. The quantitative targeted approach demonstrated an increase in free sphingoid bases, likely associated with a deregulated angiogenesis. Our findings indicate that lipid signature could play a central role in MA and that a detailed biomarker profile may contribute to untangle the complex, and still obscure, pathogenesis of MA.  相似文献   
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