Interaction of proteins in solution from small angle scattering: a perturbative approach

In this work, an improved methodology for studying interactions of proteins in solution by small-angle scattering, is presented. Unlike the most common approach, where the protein-protein correlation functions $g_{ij}(r)$ are approximated by their zero-density limit (i.e. the Boltzmann factor), we propose a more accurate representation of $g_{ij}(r)$ which takes into account terms up to the first order in the density expansion of the mean-force potential. This improvement is expected to be particulary effective in the case of strong protein-protein interactions at intermediate concentrations. The method is applied to analyse small angle X-ray scattering data obtained as a function of the ionic strength (from 7 to 507 mM) from acidic solutions of $\beta$-Lactoglobuline at the fixed concentration of 10 $\rm g L^{-1}$. The results are compared with those obtained using the zero-density approximation and show a significant improvement particularly in the more demanding case of low ionic strength.Comment: 12 pages, 3 figures, to appear in Biophysical Journal (April 2002) Due to an unfortunate name mismatch, the original submission contained an incorrect sourc

Developing a new cost‐efficient control strategy for an actual confectionery plant through the combined exploitation of experimental and numerical analysis

Achieving energy absorption reductions while improving indoor air quality is a major task when designing new air conditioning systems. A cost-effective way to improve energy efficiency without compromising the thermal comfort consists of developing better control. In the present work, an extensive experimental campaign has been coupled with a theoretical analysis with an effective approach. A simulation tool has been implemented and, through its predictions, an efficient control strategy has been developed in a system that resulted in significant energy savings and environmental benefits. Copyright © 2003 John Wiley & Sons, Ltd

A “Territorialização” do poder episcopal no Portugal Medieval. Um estudo das bullae dos Papas Pascoal II e Calisto II e os conflitos entre as dioceses de Porto, Braga e Coimbra (século XII)

The first decades of the 12 th century are a turning point in the History of Portugal . The successful military campaigns against the Muslims allowed the reorganization of the northern dioceses . This episcopal restoration policy led to a clash between Oporto, Braga and Coimbra for the diocesan frontiers . During the pontificate of Hugh of Oporto (1112-1136), the Popes directly intervened to solve this territorial conflict . The aim of this paper is to study the papal bullae granted by Paschalis II and Calixtus II in 1115 and in 1120 to Hugh Bishop of Oporto. Our goal is to demonstrate how this type of document is not a reliable representation of the territory . The value of these papal bullae , in fact, is not factual , but political and it is very important to introduce the study of both the territorialization of episcopal power in Medieval Portugal and the tight relation between local bishops and Roman Pontiff.As primeiras décadas do século XII são um ponto crucial na história de Portugal. O sucesso das campanhas militares contra os muçulmanos permitiu a reorganização das dioceses do Norte. Esta política de restauração episcopal teve como consequência um conflito entre Porto, Braga e Coimbra e durante o pontificado do bispo do Porto, Hugo (1112-1136), os papas em muitas ocasiões intervieram para resolver esta disputa territorial. O objetivo de este artigo é o estudo das bullae papais de Pascoal II e Calixto II de 1115 e 1120 em favor de Hugo do Porto. O escopo é demonstrar como este tipo de documento não é uma representação fiável do território. O valor destas bullae, efetivamente, não é factual, mas político e é muito importante para introduzir o estudo sobre a territorialização do poder episcopal no Portugal medieval e a relação muito próxima entre os bispos locais e os pontífices romanos

Role of the vanins-myeloperoxidase axis in colorectal carcinogenesis

The presence of chronic inflammation in the colonic mucosa leads to an increased risk of cancer. Among proteins involved in the regulation of mucosal inflammation and that may contribute both to structural damage of the intestinal mucosa and to intestinal carcinogenesis, there are myeloperoxidase (MPO) and vanins. The infiltration of colonic mucosa by neutrophils may promote carcinogenesis through MPO, a key enzyme contained in the lysosomes of neutrophils that regulates local inflammation and the generation of reactive oxygen species (ROS) and mutagenic species. The human vanin gene family consists of three genes: vanin-1, vanin-2 and vanin-3. All vanin molecules are pantetheinases, that hydrolyze pantetheine into pantothenic acid (vitamin B5), and cysteamine, a sulfhydryl compound. Vanin-1 loss confers an increased resistance to stress and acute intestinal inflammation, while vanin-2 regulates adhesion and transmigration of activated neutrophils. The metabolic product of these enzymes has a prominent role in the inflammation processes by affecting glutathione levels, inducing ulcers through a reduction in mucosal blood flow and oxygenation, decreasing local defense mechanisms, and in carcinogenesis by damaging DNA and regulating pathways involved in cell apoptosis, metabolism and growth, as Nrf2 and HIF-1α

Combustion CFD modeling of a spark ignited optical access engine fueled with gasoline and ethanol

Abstract In this study we present the Computational Fluid Dynamics (CFD) modeling of the combustion process using detailed chemistry in a spark-ignited (SI) optical access engine operated at part load using gasoline and ethanol as fuels. Simulation results are compared against experimental optical and indicating data. The engine is installed at the Department of Engineering of the University of Perugia, and it features a four-valve head, a transparent flat piston and a port-fuel-injection (PFI) system. Full open cycle simulations have been performed using the commercial code CONVERGE. The combustion process has been simulated using detailed chemistry and adaptive mesh refinement (AMR) to resolve in detail and track the reaction zone, in a Reynolds Averaged Navier-Stokes (RANS) modeling framework. In-cylinder pressure, heat release, and flame morphology have been compared with experimental indicating and imaging data. Tests and simulations span different air-fuel ratios in lean and rich conditions (relative air-fuel ratio λranges from 0.9 to 1.1). Results indicate that simulations are able to predict experimental data with high accuracy. Variations due to changing fuel type and air-fuel ratio are well captured. The computational cost to achieve grid-independent results has been evaluated and it is also not excessively high. Taking into account that the engine speed was quite low, i.e., 900 rpm, we conclude that, in this condition, detailed chemistry coupled with RANS works satisfactorily without turbulence chemistry interaction sub-models, and therefore without any tunings

Synthesis of Dibenzo[b,e]azepin-11-ones by Intramolecular Palladium-Catalyzed Acylation of Aryliodides with Aldehydes

The paper describes an efficient methodology for the synthesis of diversely functionalized dihydrodibenzo[b,e]azepin-11-ones based on the Pd(0)-catalyzed intramolecular acylation of aryl iodides with aldehydes

Attenuated adenomatous polyposis of the large bowel: Present and future

Attenuated adenomatous polyposis (AAP) is a poorly understood syndrome, that can be defined as the presence of 10-99 synchronous adenomas in the large bowel, and it is considered a phenotypic variant of familial adenomatous polyposis (FAP). This definition has the advantage of simplicity, but it may include sporadic multiple adenomas of the large bowel at an extreme, or FAP cases on the other side. AAP shows a milder phenotype than FAP, with an older age of onset of adenomas and cancer, and less frequent extracolonic manifestations. AAP may be diagnosed as a single case in a family or, less frequently, it may be present in other family members, and it shows distinct pattern of inheritance. In less than 50% of cases, it may be caused by adenomatous polyposis coli (APC) or MUTYH mutations, referred to as APC-associated polyposis, inherited as an autosomal dominant trait, or MUTYH - associated polyposis, which shows an autosomal recessive mechanism of inheritance, respectively. Surveillance should rely on colonoscopy at regular intervals, with removal of adenomas and careful histological examination. When removal of polyps is not possible or advanced lesions are observed, the surgical approach is mandatory, being subtotal colectomy with ileo-rectal anastomosis the treatment of choice. Studies on this syndrome are lacking, and controversies are still present on many issues, thus, other clinical and genetic studies are requested

Cherry picking or depth-oriented strategic investing? Evidence from SRI activity

Today, socially responsible investing (SRI) represents the youngest financial-services industry that investors can exploit to implement their investment strategies. Although literature in this field is growing, additional research is needed to disentangle the factors affecting the performance of SRI funds. This paper focuses on the analysis of the influence that the depth of investment strategy by SRI funds may have on the investment performance, whereas larger SRI funds have a stronger capacity to address their investment choices. We used a sample of 149 USA SRI funds referring to the Social Investment Forum (SIF) Foundation in the period 2005-2010. We found that depth of investment strategy decreases the capacity of large SRI funds to reach positive financial returns if a broad sustainability investment strategy is pursued. On the other hand, SRI funds able to focus the attention on specific environmental, social, governance, or product criteria do increase their capacity to reach positive financial performance. This paper contributes to the existing literature by examining the depth of the sustainability investment strategy by SRI funds and investigating the moderating effect that peculiar investment strategies have on the well-known relation between size and performance of SRI funds. major-bidi;mso-bidi-theme-font:major-bidi;mso-ansi-language:EN-GB;mso-fareast-language: ZH-CN;mso-bidi-language:AR-SA'>This paper analyzes the wealth distribution taking into account the reaction of the market to the alliance as an indicator of a successful strategy. It explores the case of the automobile industry, which is characterised by a high use of inter-firm cooperation, such as strategic alliances and mergers & acquisitions, to effectively compete in the global market and face the global crisis

Inflammatory pathways in the early steps of colorectal cancer development

Colorectal cancer is a major cause of cancer-related death in many countries. Colorectal carcinogenesis is a stepwise process which, from normal mucosa leads to malignancy. Many factors have been shown to influence this process, however, at present, several points remain obscure. In recent years some hypotheses have been considered on the mechanisms involved in cancer development, expecially in its early stages. Tissue injury resulting from infectious, mechanical, or chemical agents may elicit a chronic immune response resulting in cellular proliferation and regeneration. Chronic inflammation of the large bowel (as in inflammatory bowel diseases), has been associated with the subsequent development of colorectal cancer. In this review we examine the inflammatory pathways involved in the early steps of carcinogenesis, with particular emphasis on colorectal. Firstly, we describe cells and proteins recently suggested as central in the mechanism leading to tumor development. Macrophages and neutrophils are among the cells mostly involved in these processes and proteins, as cyclooxygenases and resolvins, are crucial in these inflammatory pathways. Indeed, the activation of these pathways establishes an oxidative and anaerobic microenvironment with DNA damage to epithelial cells, and shifting from an aerobic to an anaerobic metabolism. Many cellular mechanisms, such as proliferation, apoptosis, and autophagy are altered causing failure to control normal mucosa repair and renewal

Mechanical Complications of Myocardial Infarction

Complications of acute myocardial infarction are different and life threatening. Prompt diagnosis and therapy are essential. In this, chapter we will analyse mechanical complications, such as ventricular free wall rupture, ventricular septal defect, papillary muscle rupture, ischaemic mitral regurgitation, left ventricle aneurysm, and cardiogenic shock