Full-scale demonstration of biological nutrient removal in a single tank SBR process

Complete biological nutrient removal (BNR) in a single tank, sequencing batch reactor (SBR) process, is demonstrated here at full-scale on a typical domestic wastewater. The unique feature of the UniFed process is the introduction of the influent into the settled sludge blanket during the settling and decant periods of the SBR operation. This achieves suitable conditions for denitrification and anaerobic phosphate release which is critical to successful biological phosphorus removal, It also achieves a selector effect, which helps in generating a compact, well settling biomass in the reactor. The results of this demonstration show that it is possible to achieve well over 90% removal of GOD, nitrogen and phosphorus in such a process. Effluent quality achieved over a six-month operating period directly after commissioning was: 29 mg/l GOD, 0.5 mg/l NH4-N, 1.5 mg/l NOx-N and 1.5 mg/l PO4-P (50%-iles of daily samples). During an 8-day, intensive sampling period, the effluent BOD5 was

Evidence for a sub-morphological inflammatory process in the liver in haemochromatosis

Background/Aims: The role of cytokines in hepatic injury has been examined for many liver diseases however little is known of the cytokine involvement in haemochromatosis. The aim of the current study was to examine the hepatic gene expression of potential proinflammatory and profibrogenic cytokines in haemochromatosis. Methods: Interferon-gamma, interleukin-10, transforming growth factor-beta(1) and tumor necrosis factor-alpha mRNA expression was assessed in liver tissue from 20 haemochromatosis patients, eight controls and eight chronic hepatitis C patients. To assess the immunophenotype of the inflammatory infiltrate in haemochromatosis, liver sections were subjected to immunohistochemistry using markers for macrophages (CD68, HAM56, MAC387) or T cells (CD3 and CD45RO). Results: Interferon-gamma mRNA was increased in both haemochromatosis (0.29+/-0.08%, P=0.01) and hepatitis C patients (1.02+/-0.32%, P=0.03) compared to controls (0.04+/-0.01%). Interleukin-10 mRNA was significantly decreased in both haemochromatosis and hepatitis C patients (0.01+/-0.003%, P=0.008 and 0.03+/-0.015%, P=0.02, respectively) compared to controls (0.12+/-0.01%). CD3 positive T-cell number was significantly correlated with increasing hepatic iron concentration (r=0.56, P=0.03). Conclusions: This study has demonstrated a distinct pattern of cytokine gene expression in haemochromatosis, which resembles that of inflammatory conditions such as chronic hepatitis C. These factors may play a role in the development of iron-induced hepatic fibrosis in haemochromatosis. (C) 2003 European Association for the Study of the Liver. Published by Elsevier Science B.V. All rights reserved.

An approach to verifying and debugging simulation models governed by ordinary differential equations: Part 1. Methodology for residual generation

For dynamic simulations to be credible, verification of the computer code must be an integral part of the modelling process. This two-part paper describes a novel approach to verification through program testing and debugging. In Part 1, a methodology is presented for detecting and isolating coding errors using back-to-back testing. Residuals are generated by comparing the output of two independent implementations, in response to identical inputs. The key feature of the methodology is that a specially modified observer is created using one of the implementations, so as to impose an error-dependent structure on these residuals. Each error can be associated with a fixed and known subspace, permitting errors to be isolated to specific equations in the code. It is shown that the geometric properties extend to multiple errors in either one of the two implementations. Copyright (C) 2003 John Wiley Sons, Ltd.

Nitrification of high strength ammonia wastewtaer treatment - process selection is the major factor.

Biological nitrogen removal via the nitrite pathway in wastewater treatment is very important in Saving the cost of aeration and as an electron donor for denitrification. Wastewater nitrification and nitrite accumulation were carried out in a biofilm airlift reactor with autotrophic nitrifying biofilm. The biofilm reactor showed almost complete nitrification and most of the oxidized ammonium was present as nitrite at the ammonium load of 1.5 to 3.5 kg N/m3.d. Nitrite accumulation was stably achieved by the selective inhibition of nitrite oxidizers with free ammonia and dissolved oxygen limitation. Stable 100% conversion to nitrite could also be achieved even under the absence of free ammonia inhibition on nitrite oxidizers. Batch ammonium oxidation and nitrite oxidation with nitrite accumulating nitrifying biofilm showed that nitrite Oxidation was completely inhibited when free ammonia is higher than 0.2 mg N/L. However, nitrite oxidation activity was recovered as soon as the free ammonia concentration was below the threshold level when dissolved oxygen concentration was not the limiting factor. Fluorescence in situ hybridization analysis of cryosectioned nitrite accumulating nitrifying biofilm showed that the β-subclass of Proteobacteria, where ammonia oxidizers belong, was distributed outside the biofilm whereas the α-subclass of Proteobacteria, where nitrite oxidizers belong, was found mainly in the inner part of the biofilm. It is likely that dissolved oxygen deficiency or limitation in the inner part of the nitrifying biofilm, where nitrite oxidizers exist, is responsible for the complete shut down of the nitrite oxidizers activity under the absence of free ammonia inhibition.

Dehydration converts DsbG crystal diffraction from low to high resolution

Diffraction quality crystals are essential for crystallographic studies of protein structure, and the production of poorly diffracting crystals is often regarded as a dead end in the process. Here we show a dramatic improvement of poorly diffracting DsbG crystals allowing high-resolution diffraction data measurement. Before dehydration, the crystals are fragile and the diffraction pattern is streaky, extending to 10 Angstrom resolution. After dehydration, there is a spectacular improvement, with the diffraction pattern extending to 2 Angstrom resolution. This and other recent results show that dehydration is a simple, rapid, and inexpensive approach to convert poor quality crystals into diffraction quality crystals.

A investigação da construção de modelos no estudo de um tópico de física utilizando um ambiente de modelagem computacional qualitativo

A integração de tecnologias de informação e comunicação no contexto educacional tem sido tema de diversos congressos e simpósios ao redor do mundo e no Brasil. Neste sentido, vários estudos têm sido realizados com o objetivo de se obter metodologias que tornem efetivo o emprego das novas tecnologias no ensino. Este artigo mostra um estudo que investigou a interação entre estudantes universitários da área de ciências exatas e um ambiente de modelagem computacional qualitativo em atividades de modelagem expressiva. Os resultados obtidos mostram que os estudantes foram capazes de criar e modificar o modelo do sistema proposto a partir de suas próprias concepções.

China's proposing behavior in Global Governance: the cases of the WTO Doha Round negotiation and G-20 process

This article examines China's proposals on the reform of global governance, and discusses the main features of China's proposing behavior in the cases of the WTO Doha Round negotiation and G-20 Process. The main findings are: (1) in the critical junctures of global governance reform, China engaged the reform of the global governance institutions proactively, and put forward a series of reform proposals; (2) in proposing behavior, China argued the global governance institutions should be properly adjusted without intention to change the basic principles, refrained from playing a leadership role while proposing jointly with other countries, and upheld the principled idea of pro-development.

The UN peacebuilding process: an analysis of its shortcomings in Timor-Leste

This paper brings a comprehensive analysis of the peacebuilding process conducted by the UN in Timor-Leste. Drawing on fieldwork, interviews, and secondary sources, the paper brings light to the main fragilities of this process. Firstly, the paper briefly outlines the scholarly debate around UN peacebuilding process. Then, the paper brings an overview of the UN missions deployed to Timor-Leste. Finally, the paper identifies the major limitations of such engagement. By highlighting the main flaws of this peacebuilding process, the paper opens the space for (re)thinking alternative ways of building peace in post-conflict scenarios.

Modelling the Mechanical Behavior of Polymer-Based Nanocomposites

Molecular dynamics simulations were employed to analyze the mechanical properties of polymer-based nanocomposites with varying nanofiber network parameters. The study was focused on nanofiber aspect ratio, concentration and initial orientation. The reinforcing phase affects the behavior of the polymeric nanocomposite. Simulations have shown that the fiber concentration has a significant effect on the properties, with higher loadings resulting in higher stress levels and higher stiffness, matching the general behavior from experimental knowledge in this field. The results also indicate that, within the studied range, the observed effect of the aspect ratio and initial orientation is smaller than that of the concentration, and that these two parameters are interrelated.

Estimating Local Part Thickness in Midplane Meshes for Finite Element Analysis

Within the development of motor vehicles, crash safety (e.g. occupant protection, pedestrian protection, low speed damageability), is one of the most important attributes. In order to be able to fulfill the increased requirements in the framework of shorter cycle times and rising pressure to reduce costs, car manufacturers keep intensifying the use of virtual development tools such as those in the domain of Computer Aided Engineering (CAE). For crash simulations, the explicit finite element method (FEM) is applied. The accuracy of the simulation process is highly dependent on the accuracy of the simulation model, including the midplane mesh. One of the roughest approximations typically made is the actual part thickness which, in reality, can vary locally. However, almost always a constant thickness value is defined throughout the entire part due to complexity reasons. On the other hand, for precise fracture analysis within FEM, the correct thickness consideration is one key enabler. Thus, availability of per element thickness information, which does not exist explicitly in the FEM model, can significantly contribute to an improved crash simulation quality, especially regarding fracture prediction. Even though the thickness is not explicitly available from the FEM model, it can be inferred from the original CAD geometric model through geometric calculations. This paper proposes and compares two thickness estimation algorithms based on ray tracing and nearest neighbour 3D range searches. A systematic quantitative analysis of the accuracy of both algorithms is presented, as well as a thorough identification of particular geometric arrangements under which their accuracy can be compared. These results enable the identification of each technique’s weaknesses and hint towards a new, integrated, approach to the problem that linearly combines the estimates produced by each algorithm.

Exploring the interdisciplinary process in design education

The work presented herein follows an ongoing research that aims to analyze methodological practices to be applied in Design Education. A reflection about methodological strategies in Design Education and the function of drawing in Design represents the beginning of this study. Then, we developed an interdisciplinary pedagogical experience with the Graphic Design 1st grade students from our institution (IPCA). In the current academic year, 2013/2014, we continue to evolve this project, introducing changes in the initial proposal. Major alterations focused on the aspects that could be strengthened in terms of interdisciplinarity. In this article, the authors describe those changes and discuss the outcomes of the novel proposal. As we have already reported, this investigation follows a reflection about working methods to be adopted in Design Education. This is in accordance with other previously published works that purpose the enlargement of Design into new knowledge fields such as Experience or Service Design, changing not only the role of the graphic designer, but also the skills required to be a professional designer (Alain Findelli, 2001), (Brian Lawson, 2006), (Ciampa-Brewer, 2010). Furthermore, concepts such as cooperation or multidisciplinary design, amongst others, have been frequently debated as design teaching strategies (Heller and Talarico, 2011, pp. 82-85). These educational approaches also have an impact on our research. The analysis of all these authors’ contributions together with a reflection on our teaching practice allowed us to propose an improved interdisciplinary intervention.

The strategic management of creation process and of change: a theoretical contribute from the perspective of tourism

The entrepreneurship and innovation have been gradually gaining ground in the academic community as a field of study. However, the interpretations surrounding fragmented, without a univocal definition. In last decades, tourism has received greater attention from researchers in various sciences, varying only by the different emphases considered: economic, social, cultural and environmental. As other emerging sectors in a modern economy, tourism is a dynamic and ever-changing industry. The study has as purpose to provide a better understanding regarding the essence of entrepreneurship: theoretical and practical implications from the perspective of tourism. Regarding the methodology used here, this is a conceptual paper with a literature review that brings together the major components of entrepreneurship and its implications tourist perspective and conceptual model of the dynamic nature of the Triggering Process and innovation (e.g. iTravey, Interactive Stores, Tourist Transportable Tower).