589 research outputs found
From Urban Systems to Sustainable Competitive Metropolitan Regions
No full textUna raccolta di essay sullo sviluppo della' citta' che illustra come le citta' si sono sviluppate per affrontare meglio le questioni di competitivita' e di sostenibilita'.Alla base della raccolta le ricerche di EURICUR dell'Erasmus University Rotterdam
Degradation of organic micropollutants by advanced oxidation through UV/H2O2
No full textDrinking water company Dunea Duin en Water produces drinking water from the Meuse River, which contains a variety of organic micropollutants (OMPs) from upstream activity. OMPs found in Dunea’s source are plant protection products, pharmaceuticals, hormones and endocrine disruptors and X-ray contrast media. Continues development of measuring equipment has resulted in lower detection limits for most substances and measuring programs are expended yearly. Consequently, more substances are found in the Meuse River and other surface water bodies. Dunea is currently performing research to extend the multiple barrier treatment with advanced oxidation processes (AOP) via UV and hydrogen peroxide. Mostly medium pressure (MP) mercury vapour ultraviolet lamps are used that emit a broad spectrum of light, coinciding with the absorbance spectrum of many substances, which results in a high photolytic capacity. Low pressure (LP) mercury vapour lamps emit ultraviolet light at just one single wavelength (254 nm). Consequently, the direct photolysis of target substances is less effective and the yield of hydroxyl radicals is lower compared to MP lamps. However, LP lamps have advantages over MP lamps such as significantly lower energy consumption and fewer by-products such as Assimilable Organic Carbon (AOC) and nitrite are formed. The objective of this research is formulated as follows: Performance comparison of low pressure versus medium pressure mercury vapour lamps in advanced oxidation via UV/H2O2, by means of experimental research with a pilot-scale set-up.Sanitary EngineeringWatermanagementCivil Engineering and Geoscience
Enabling high-throughput ligation-independent cloning and protein expression for the family of ubiquitin specific proteases
No full textSkeletal muscle fibre-type shifting and metabolic profile in patients with chronic obstructive pulmonary disease
No full textSkeletal muscle fibre-type shifting and metabolic profile in patients with chronic obstructive pulmonary disease. Gosker HR, van Mameren H, van Dijk PJ, Engelen MP, van der Vusse GJ, Wouters EF, Schols AM. Dept of Pulmonology, University of Maastricht, The Netherlands. [email protected] The aim of this study was to examine the nature of fibre-type redistribution in relation to fibre metabolic profile in the vastus lateralis in chronic obstructive pulmonary disease (COPD) and COPD subtypes. Fifteen COPD patients (eight with emphysema stratified by high-resolution computed tomography) and 15 healthy control subjects were studied. A combination of myofibrillar adenosine triphosphatase staining and immunohistochemistry was used to identify pure, as well as hybrid fibre types. For oxidative capacity, fibres were stained for cytochrome c oxidase and succinate dehydrogenase activities, and glycogen phosphorylase for glycolytic capacity. The proportion of type-I fibres in COPD patients was markedly lower (16% versus 42%), especially in emphysema, and the proportion of hybrid fibres was higher (29% versus 16%) compared to controls. The proportion of fibres staining positive for oxidative enzymes was lower in COPD patients, which correlated with the proportion of type-I fibres. In COPD oxidative capacity was lower within IIA fibres. The authors conclude that fibre-type transitions are involved in the fibre-type redistribution in chronic obstructive pulmonary disease. Low oxidative capacity is closely related to the proportion of type-I fibres, but an additional reduction of oxidative enzyme activity is present within IIA fibres. Fibre-type abnormalities may be aggravated in emphysema
Structures of optimal policies in MDPs with unbounded jumps:the state of our art
No full textThe derivation of structural properties of countable state Markov decision processes (MDPs) is generally based on sample path methods or value iteration arguments. In the latter case, the method is to inductively prove the structural properties of interest for the n-horizon value function. A limit argument then should allow to deduce the structural properties for the infinite-horizon value function.\u3cbr/\u3eIn the case of discrete time MDPs with the objective to minimise the total expected α-discounted cost, this procedure is justified under mild conditions. When the objective is to minimise the long run average expected cost, value iteration does not necessarily converge. Allowing time to be continuous does not generate any further complications when the jump rates are bounded as a function of state, due to applicability of uniformisation. However, when the jump rates are unbounded as a function of state, uniformisation is only applicable after a suitable perturbation of the jump rates that does not destroy the desired structural properties. Thus, also a second limit argument is required.\u3cbr/\u3eThe importance of unbounded rate countable state MDPs has increased lately, due to applications modelling customer or patient impatience and abandonment. The theory validating the required limit arguments however does not seem to be complete, and results are scattered over the literature.\u3cbr/\u3eIn this chapter our objective has been to provide a systematic way to tackle this problem under relatively mild conditions, and to provide the necessary theory validating the presented approach. The base model is a parametrised Markov process (MP): both perturbed MPs and MDPs are special cases of a parametrised MP. The advantage is that the parameter can simultaneously model a policy and a perturbatio
Human amniotic fluid glycoproteins expressing sialyl Lewis carbohydrate antigens stimulate progesterone production in human trophoblasts in vitro
No full textBackground: Progesterone is thought to mediate immune modulator effects by regulating uterine responsiveness. The aim of the study was to clarify the effect of transferrin and glycodelin A (former name PP14) as sialyl Lewis X-expressing glycoproteins on the release of progesterone by trophoblast cells in vitro. Methods: Cytotrophoblast cells were prepared from human term placentas by standard dispersion of villous tissue followed by a Percoll gradient centrifugation step. Trophoblasts were incubated with varying concentrations (50-300 mug/ml) of human amniotic fluid- and serum-transferrin as well as with glycodelin A. Culture supernatants were assayed for progesterone, human chorionic gonadotropin (hCG) and cortisol by enzyme immunometric methods. Results: The release of progesterone is increased in amniotic fluid transferrin- and glycodelin A-treated trophoblast cell cultures compared to untreated trophoblast cells. There is no relation between transferrin and the hCG or cortisol production of trophoblast cells. Conclusion: The results suggest that sialyl Lewis carbohydrate antigen-expressing amniotic fluid glycoproteins modulate the endocrine function of trophoblasts in culture by upregulating progesterone production. Copyright (C) 2004 S. Karger AG, Basel
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