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1.
Wastewater treatment plant operators encounter complex operational problems related to the activated sludge process and usually respond to these by applying their own intuition and by taking advantage of what they have learnt from past experiences of similar problems. However, previous process experiences are not easy to integrate in numerical control, and new tools must be developed to enable re-use of plant operating experience. The aim of this paper is to investigate the usefulness of a case-based reasoning (CBR) approach to apply learning and re-use of knowledge gained during past incidents to confront actual complex problems through the IWA/COST Benchmark protocol. A case study shows that the proposed CBR system achieves a significant improvement of the benchmark plant performance when facing a high-flow event disturbance.  相似文献   
2.
The identification of adequate wastewater treatment for small communities is a complex problem since it demands a combination of data from different sources, such as aspects of the community and landscape, the receiving environment and the available wastewater treatment technologies. The Catalan Water Agency (Agència Catalana de l'Aigua) considered using an EDSS (Environmental Decision Support System) as a tool to help water managers select the most adequate treatment for the urban wastewater of nearly 3,500 small communities in Catalonia (Spain). From that moment, EDSS was applied to all the river basins in Catalonia. In this paper the authors present the results obtained for the 76 small communities located in one of these river basins: the Fluvia River Basin. The characteristics of the community used in the reasoning process of the EDSS, the list of selected wastewater treatment alternatives, the technical environmental justification for the selected treatments and the reasons for discarding, favouring or disadvantaging them are presented. Finally, some results for the Fluvia River Basin are compared with those obtained in other Catalan river basins with different characteristics in order to evaluate which are the significant features in identifying adequate wastewater treatments.  相似文献   
3.
The intrinsic value of animals and their place in human society influence veterinary practice. The role-responsibility of the veterinarian is under pressure of practical circumstances, client requests and constraints of breeding and management systems. A reflection on human needs as related to the intrinsic value and welfare of animals, is required inside and outside the profession. It is in the interest of life to think and act out of total ecological concepts. In order to be better prepared to deal with ethical problems in practice, students should receive adequate training. The assumed value-free research and the need for outside financial support are a hindrance for research projects that aim at sustainability of human and animal life. It is concluded that the profession needs a philosophy about her objectives.  相似文献   
4.
Recent research has found that family caregivers do not discuss their caregiving in terms of tasks but instead describe their care as shaped by concerns, commitments and goals. The purpose of this paper is to challenge the ways in which nurses approach the family caregiving process and to explore possibilities for evolving nursing knowledge by questioning existing practice in the light of developing insight into the ways in which being a family caregiver is meaningful. A critique of the philosophical orientations of rationalism and empiricism provides a platform to discuss the merits of a Heideggerian phenomenological approach in assisting nurses to better understand family caring experience. Such critique serves to support the notion of displacing the traditional scientific view as the prime means of disclosing truth, acknowledging alternative ways of knowing.  相似文献   
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6.
Phenylketonuria (PKU) is a rare metabolic disease caused by variations in a human gene, PAH, encoding phenylalanine hydroxylase (PAH), and the enzyme converting the essential amino acid phenylalanine into tyrosine. Many PKU-causing variations compromise the conformational stability of the encoded enzyme, decreasing or abolishing its catalytic activity, and leading to an elevated concentration of phenylalanine in the blood, which is neurotoxic. Several therapeutic approaches have been developed to treat the more severe manifestations of the disorder, but they are either not entirely effective or difficult to adhere to throughout life. In a search for novel pharmacological chaperones to treat PKU, a lead compound was discovered (compound IV) that exhibited promising in vitro and in vivo chaperoning activity on PAH. The structure of the PAH-IV complex has been reported. Here, using alchemical free energy calculations (AFEC) on the structure of the PAH-IV complex, we design a new generation of compound IV-analogues with a higher affinity for the enzyme. Seventeen novel analogues were synthesized, and thermal shift and isothermal titration calorimetry (ITC) assays were performed to experimentally evaluate their stabilizing effect and their affinity for the enzyme. Most of the new derivatives bind to PAH tighter than lead compound IV and induce a greater thermostabilization of the enzyme upon binding. Importantly, the correspondence between the calculated alchemical binding free energies and the experimentally determined ΔΔGb values is excellent, which supports the use of AFEC to design pharmacological chaperones to treat PKU using the X-ray structure of their complexes with the target PAH enzyme.  相似文献   
7.
Herein, we present a prototype of a photovoltaic module that combines a luminescent solar concentrator integrating one‐dimensional photonic crystals and in‐plane CuInGaSe2 (CIGS) solar cells. Highly uniform and wide‐area nanostructured multilayers with photonic crystal properties were deposited by a cost‐efficient and scalable liquid processing amenable to large‐scale fabrication. Their role is to both maximize light absorption in the targeted spectral range, determined by the fluorophore employed, and minimize losses caused by emission at angles within the escape cone of the planar concentrator. From a structural perspective, the porous nature of the layers facilitates the integration with the thermoplastic polymers typically used to encapsulate and seal these modules. Judicious design of the module geometry, as well as of the optical properties of the dielectric mirrors employed, allows optimizing light guiding and hence photovoltaic performance while preserving a great deal of transparency. Optimized in‐plane designs like the one herein proposed are of relevance for building integrated photovoltaics, as ease of fabrication, long‐term stability and improved performance are simultaneously achieved. © 2015 The Authors. Progress in Photovoltaics: Research and Applications published by John Wiley & Sons Ltd.  相似文献   
8.
The effect of including distilled rosemary leaf in the diet of pregnant ewes on subsequent lamb meat quality was studied. Thirty-six Segureña ewes were randomly assigned to three homogeneous groups. One group was fed a basal diet (BD) as control while the diet of the other two groups was modified by substituting 10% (R1) and 20% (R2) of the BD with a pellet made from 50% barley and 50% of distilled rosemary leaves (DRL). Meat spoilage (TVC, PSY and MYC), TBARS, CIELab coordinates and the sensory characteristics contribution of fresh lamb meat packed in MAP (70% O2:30% CO2) were analyzed on days 0, 7, 14 and 21. In general, R1 and R2 had higher a* values, better scores for meat and fat colour (P < 0.05) and lower TBARS and rancid odour (P < 0.05), than the control samples. The total viable count was lower in meat DRL. No statistically significant differences were detected between the two treatments (10–20% DRL).  相似文献   
9.
1. An unidentified oxisuran metabolite which had been observed in animal urine was biosynthesized by incubating [14C]oxisuran with rat liver cytosol. 2. The metabolite, isolated by preparative t.l.c. and extraction, was identified as oxisuran alcohol sulphide by mass fragmentography. Confirmation of this identification was obtained by biosynthesis of the same compound from oxisuran sulphide. 3. The 9000 g supernatant liquid from rat liver was less effective than cytosol in reducing oxisuran to its alcohol sulphide. Neither rat liver fraction reduced oxisuran alcohol sulphoxides to sulphide. 4. The 9000 g fraction oxidized oxisuran and oxisuran alcohol sulphoxide to oxisuran alcohol sulphone.  相似文献   
10.
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