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The automotive sector is one of the key users of adhesive bonding, adopting this technology for the manufacture of high performance multi material structures, seeking to reduce vehicle weight and increase overall stiffness. In these industrial applications, the design of bonded structures is supported by numerical models, which require the determination of the mechanical properties of the adhesives and the adherends, taking into account factors such as temperature and strain rate dependence. However, while the design of bonded joints under quasi-static loadings is currently well understood, the design of impact resistant structures is much more complex, since it requires the establishment of accurate models for the strain rate dependent behaviour of the materials used in vehicle construction. This document provides an updated outlook on the research work being performed by the authors in this specific field. Most of the work is devoted to the analysis of the effects of strain rate on the behaviour of adhesives and adhesive joints. This includes high strain rate characterisation of the mechanical behaviour of modern crash resistant adhesives, using both standardised and custom testing procedures. Special experimental equipment has also been developed for impact testing procedures, including high strain rates and mixed mode conditions and full-size specimens.

The determinants of profitability in small and medium sized service companies in Portugal are studied using data from 273 enterprises. Findings show that specific determinants have a nonlinear relationship with these companies' profitability. Managerial control long-term debt, and size catalyze profitability in the lower quantiles of profitability distribution.

The profitability determinants of Portuguese service industries are examined based on various panel models. Profitability has been found to be persistent over time for larger companies with growth. Diversification, motivation and innovation are seen to contribute to profitability.

A study was conducted to show rejection of Gibrat's law for Portuguese companies in the service industry, using dynamic panel estimators. Company growth depends positively on growth in the previous period and on debt, and depends negatively on size. Information about the relationship between ownership control and growth is also presented.

A study was conducted to examine the relationship between tourism and economic growth using appropriate panel data methods. Findings indicate that tourism is a positive determinant of economic growth both in a broad sample of countries and in a sample of poor countries. Results also show that tourism is not more relevant in small countries than in a general sample.

A quantile regression approach is used to illustrate the negative effect of leverage on labor productivity. It is found that total assets and foreign ownership has a positive effect to the labor productivity of Portuguese firms.

The assessment of monetary values of cockle fishery management in the Dutch Wadden Sea for Dutch citizens, local residents and tourists is presented. The utility of a nested logit model to assess the impact of the providing no-choice options in attribute-based valuation experiments is discussed.

The study aims to present new constants of ignition delay based on the Arrhenius model for two diesel fuel surrogates formulated from four components (n-Hexadecane, Heptamethylnonane, Decahydro-naphthalene, and 1-Methyl-naphthalene) as a function of temperature and pressure, obtained by simulation in an adiabatic, homogeneous and constant pressure reactor using the Cantera simulator. The reaction was considered stoichiometric, with a temperature and pressure range varying from 700 to 2200 K and 40 to 120 atm, typical values found in the combustion chamber of turbocharged compression ignition engines. It was found that two-stage combustion occurs for temperatures between 700 and 1000 K (for pressure of 80 atm). When the combustion occurs in two-stages, we detail the ignition delay of each stage, and its first-stage fraction are presented. Surrogate fuels was modeled in 35 and 45 cetane numbers and 48 and 35 threshold soot index, respectively, to compare low and medium fuels in cetane numbers. The main application of these models relates to stochastic combustion models, which require fast models with low computational cost. The main differential of this study refers to its description of two-stage combustion, if it occurs. The model does not consider the physical ignition delay, referring to atomization, mixing and heating of the fuel. Results were compared with models from the literature, showing good agreement and presented intermediate values when compared with the literature.

What is the role of festivals in contemporary cities? What are the networks of meaning established between cultural festivals and the city based on the experiences of the Virada Cultural in São Paulo and the Mexefest in Lisbon? How can these events be linked with tourism, city branding, urban renewal projects and social control? What are the different roles played by festivals in contemporary society? This paper engages with these questions through reflections generated from fieldwork conducted at the Mexefest Festival which has been organized in Lisbon by Música no Coração Productions since 2011; and the Virada Cultural which has been organized in São Paulo by the City Hall since 2005. Using Actor Network Theory and based on direct observations, documentary analysis and literature review, it will investigate the ways in which cultural festivals can function as mediators of certain aspects of the social-urban dynamic. Thus, it will attempt to contribute to the discussion of such themes as the relation between culture and economic development, social control by urban musical festivals, city renewal processes, tourism and city branding.

The increasingly larger use of adhesive joints in the automotive industry demands a full comprehension of the adhesive behaviour when subjected to dynamic loadings. So far, some authors studied the effect of the strain rate regarding the adhesives performance, usually for the range of approximately 0–105/s; nevertheless, few studies are clear regarding the method used to calculate strain rate, especially when fracture mechanics analysis is the focus of study. Those who present approaches to assess the values of strain rate usually consider a constant value for each test. In this paper, a numerical approach is proposed to assess the strain rate in modes I and II in double cantilever beam and end notch flexure tests, respectively. The results of this study demonstrate that the strain rate in the adhesive bondline along the crack propagation in the double cantilever beam and end notch flexure tests is not constant when loaded at a constant cross-head speed. This finding also helps to justify why experimental R-curves of double cantilever beam tests, when loaded at speeds above quasi-static conditions, do not have a perfect plateau contrasting with those, usually presented by numerical simulations, that do not take into account the effect of the strain rate.

One of the world’s efforts is to mitigate the greenhouse effect, and the increase in thermal efficiency is a way to reduce the CO2emissions. Models of simulation of thermodynamic nature are useful to predict the performance of internal combustion engines. Once set up with operational characteristics, the simulation is relatively fast and does not need complex and expansive experimental apparatus to set the engine’s best parameters. The aim of this study is to build a phenomenological model to predict the performance of diesel engines, to evaluate its characteristics with experimental results, and propose thermal improvements by testing new operation parameters. In addition, this simulation model contains a blowby routine, unusual in thermodynamic models. First, a direct-injection diesel engine equipped with turbocharger and aftercooler was simulated under four operating test conditions: (1) max load and speed; (2) max speed and partial load; (3) max load and partial speed; (4) partial load and speed. The results show the experimental heat-release profile by the combustion is essential for the good agreement between the simulation and the experimental results, whose relative errors were −0.766, −0.148, −1.126, and 1.371% to the indicated shaft power for the Tests 1–4, respectively. In a second investigation, the engine simulation was made by varying the start of injection (SOI) of the Test (1). Advancing the SOI from 4.8° to 28° BTDC, the specific fuel consumption decreased 18.26%, and the indicated shaft power increased 22.37%. This article shows that a regular commercial diesel engine has a large field to improve the thermal performance, and the thermodynamic simulation fits well to support the decision of an engine project.

Diabetes is a disease linked to pathologies, such as chronic inflammation, neuropathy, and pain. The synthesis by the Claisen−Schmidt condensation reaction aims to obtain medium to high yield chalconic derivatives. Studies for the synthesis of new chalcone molecules aim at the structural manipulation of aromatic rings, as well as the replacement of rings by heterocycles, and combination through chemical reactions of synthesized structures with other molecules, in order to enhance biological activity. A chalcone was synthesized and evaluated for its antinociceptive, anti-inflammatory and hypoglycemic effect in adult zebrafish. In addition to reducing nociceptive behavior, chalcone (40 mg/kg) reversed post-treatment-induced acute and chronic hyperglycemia and reduced carrageenan-induced abdominal edema in zebrafish. It also showed an inhibitory effect on NO production in J774A.1 cells. When compared with the control groups, the oxidative stress generated after chronic hyperglycemia and after induction of abdominal edema was significantly reduced by chalcone. Molecular docking simulations of chalcone with Cox -1, Cox-2, and TRPA1 channel enzymes were performed and indicated that chalcone has a higher affinity for the COX-1 enzyme and 4 interactions with the TRPA1 channel. Chalcone also showed good pharmacokinetic properties as assessed by ADMET.

Obesity remains a global problem. In search of phytochemicals that have antiobesity potential, this study evaluated α,β-amyrin, a triter-penoid mixture from Protium heptaphyllum, on high-fat diet-induced obesity in mice. Groups of mice (n = 8) were fed a normal diet or a high-fat diet, and were orally treated or not treated with either α,β-amyrin (10 or 20 mg/kg) or sibutramine (10 mg/kg) for 15 weeks. Variables measured at termination were body weight, visceral fat accumulation, adipocyte surface area, peroxisome proliferator-activated receptor gamma, and lipoprotein lipase expressions in adipose tissue, the levels of plasma glucose and insulin, the satiety hormones ghrelin and leptin, the digestive enzymes amylase and lipase, and the inflammatory mediators TNF-α, interleukin-6, and MCP-1. Results showed that α,β-amyrin treatment resulted in lower high-fat diet-induced increases in body weight, visceral fat content, adipocyte surface area, peroxisome proliferator-activated receptor gamma, and lipoprotein lipase expressions, and blood glucose and insulin levels. Additionally, the markedly elevated leptin and decreased ghrelin levels seen in the high-fat diet-fed control mice were significantly modulated by α,β-amyrin treatment. Furthermore, α,β-amyrin decreased serum TNF-α and MCP-1. These results suggest that α,β-amyrin could be beneficial in reducing high-fat diet-induced obesity and associated disorders via modulation of enzymatic, hormonal, and inflammatory responses. [ABSTRACT FROM AUTHOR]

•Resistance training improves body adiposity, metabolic risk, and inflammation in postmenopausal and older females.•High-volume resistance training elicits greater improvements in metabolic risk and inflammation outcomes.•We identified an optimal dosage for resistance training prescription in this population.

The objective of this retrospective study was to evaluate some epidemiological characteristics, surgical treatment methods, and complications of cases involving mandibular fractures. Records from 119 patients treated for mandibular fractures between January 2006 and December 2011 were analyzed.

It is clear that climate change involves changes in temperature and precipitation and, therefore, directly affects land productivity. However, this is not the only channel for climatic change to affect agro-systems. Biodiversity is also subject to climatic change. The present paper illustrates a unique attempt to economically assess the potential effects of climate change induced impacts of biodiversity on the agricultural sector in terms of changes in land productivity, changes in agricultural output and, ultimately, changes in national GDPs. Economic valuation shows that climate change induced impacts on biodiversity cause significant changes in GDP. However, the intensity of these changes varies across the economies under consideration. Some countries, and respective economies, show to be less resilient than others and, most of the time, the welfare changes involved clearly signal the presence of winners and losers. For example, the majority of non-EU Mediterranean economies are subject to a negative impact in their national GDP due to climate change-induced impacts on biodiversity that will be hampering the negative effect of climatic conditions on agro-ecosystems. These results reiterate the importance of welfare analyses of climate change-caused impacts on biodiversity that focus on the redistributive aspects involved with these impacts.

Considering two samples of Portuguese SMEs: 582 young SMEs and 1654 old SMEs, using the two-step estimation method and quantile regressions, the empirical evidence allows us to conclude that the determinants of investment have a different impact on young and old SMEs, depending on a firm’ level of investment. In the framework of Acceleration Principle and Neoclassical Theories, the determinants are relevant in explaining the investment of young and old SMEs with high levels of investment. The Growth Domestic Product, as the investment determinant of Acceleration Principle Theory, has a greater impact on the investment of young SMEs with high levels of investment. Sales, as the investment determinant of Neoclassical Theory, have greater impact on the investment of old SMEs with high levels of investment. Cash flow, as the investment determinant of Free Cash Flow Theory, is important in explaining the investment of young and old SMEs with low levels of investment. However, cash flow has greater impact on the investment of young SMEs with low levels of investment. The empirical evidence obtained allows us to make suggestions for policy-makers and the owners/managers of Portuguese SMEs.

AbstractBased on a sample of 182 Portuguese fitness SMEs we study the investment determinants of fitness SMEs in Portugal. The multiple empirical evidence obtained in this study lets us conclude that the main explanatory theories of firm investment cannot be considered mutually exclusive in explaining the investment of Portuguese fitness SMEs, since: 1) they adjust investment as a function of sales, corroborating the assumptions of Neoclassical theory; 2) cash flow is an important financial resource for investment, corroborating the assumptions of Free Cash Flow theory; and 3) external finance, namely debt, is a restrictive determinant of investment, which corroborates the assumptions of Agency theory. Besides these results, we find that growth opportunities and government subsidies are positive determinants of investment in Portuguese fitness SMEs, and the financial crisis of 2008 has a negative influence on investment in Portuguese fitness SMEs. The financial crisis of 2008 also means greater relative importance of cash flow and government subsidies for increased investment, and debt for diminished investment, in fitness SMEs.

Diabetes mellitus represents an independent risk factor for contrast-induced acute kidney injury. We report the results of a prespecified substudy of patients with diabetes mellitus included in the Acetylcysteine for Contrast-Induced Nephropathy Trial (ACT), the largest randomized study evaluating the effects of acetylcysteine for the prevention of contrast-induced acute kidney injury conducted to date.

AbstractThis paper analyses if ownership structure is an important determinant of capital structure decisions, on the basis of two sub-samples of family-owned and non-family owned SMEs, and using panel data models. The results suggest that family ownership is an important determinant for: i) the variations of short and long-term debt stimulated by financial deficit; ii) the speed of adjustment of short and long-term debt towards the respective target levels; and iii) the relationships between determinants and short-term debt and long-term debt. In general, the capital structure decisions of family-owned SMEs are closer to what is forecast by trade-off theory than those of non-family owned SMEs, whereas the capital structure decisions of non-family owned SMEs are closer to the forecasts of pecking order theory than those of family-owned SMEs.

The Sterculia striata ethanolic extract (Ss-EtOH) inhibited gastric lesions induced by ethanol, HCl/ethanol, and ischemia/reperfusion, but not those induced by indomethacin, and did not alter the gastric secretion. Ss-EtOH restored the catalase activity and content of nonprotein sulfhydryl groups in the stomach of mice treated with ethanol. The gastroprotection induced by Ss-EtOH in the ethanol-induced gastric lesion model was abolished by NG-nitro- L-arginine methyl ester (L-NAME) pretreatment, suggesting the involvement of nitric oxide and antioxidant compounds, but not prostaglandins, in this activity. Lupeol obtained from Ss-EtOH promoted gastroprotection as well as the extract at the same dose, and it must therefore contribute to the observed effects

Abstract:A monetary valuation study of marine management in the Dutch Wadden Sea, the largest natural area of the Netherlands, is presented. The study is motivated by a conflict between shellfisheries and large populations of birds that forage on cockles. Different management scenarios are valued using multiple stakeholders, namely Dutch citizens, local residents, tourists, policy makers, and natural scientists. A considerable difference in willingness to pay (WTP) between these groups is found. In addition, the influence of motivational profiles is examined. Estimates confirm the presence of two such motivations, namely, material and moral warm glow. These allow for decomposition and correction of the WTP estimates.

The bonding energetics in a variety of alkaline metal, alkoxides and phenoxides, MOR, was investigated based on the corresponding enthalpies of formation in the crystalline state determined by reaction-solution calorimetry. The results obtained at 298.15 K were as follows: ΔfH$\rm{_{m}^{\,o}}$ (MOR, cr)/kJ mol⁻¹ = 382.7±1.4 (LiOC6H5), 513.6±2.5 (NaO-nC6H13), 326.4±1.4 (NaOC6H5), 375.2±3.4 (KOCH3), 434.5±2.7 (KOC2H5), 467.1±5.2 (KO-nC3H7), 459.3±2.1 (KO-nC4H9), 464.6±5.7 (KO-tC4H9), 464.3±2.5 (KO-nC6H13), 333.3±3.1 (KOC6H5), 380.6±2.9 (RbOCH3), 434.1±2.9 (RbOC2H5), 345.3±2.9 (LiOC6H5), 379.1±3.0 (CsOCH3), 432.3±3.1 (CsOC2H5), 466.9±5.0 (CsO-nC3H7), 461.3±3.5 (CsO-nC4H9), 461.9±2.5 (CsO-tC4H9), 349.2±1.4 (CsOC6H5). These results together with revised ΔfH$\rm{_{m}^{\,o}}$ (MOR, cr) values from the literature, were used to derive a consistent set of lattice energies for the MOR compounds and discuss general trends in the structure–energetics relationship based on the Kapustinskii equation.

The energetics of the oxidative additive of I2 to [Ir(Μ-L)(CO)2]2 [L =t-buthylthiolate (StBu), 3,5-dimethylpyrazolate (3,5-Me2pz), and 7-azaindolate (7-aza)] complexes was investigated by using the results of reaction-solution calorimetric measurements, X-ray structure determinations, and extended Hückel (EH) molecular orbital calculations. The addition of 1 mol of iodine to 1 mol of [Ir(Μ-L)(CO)2]2, in toluene, leads to [Ir(Μ-L)(I)(CO)2]2, with the formation of two Ir-I bonds and one Ir-Ir bond. The following enthalpies of reaction were obtained for this process: −125.8±4.9 kJ mol−1 (L = StBu), −152.0±3.8 kJ mol−1 (L=3,5-Me2pz), and −205.9±9.9 kJ mol¹ (L=7-aza). These results are consistent with a possible decrease of the strain associated with the formation of three-, four-, and five-membered rings, respectively, in the corresponding products, as suggested by the results of EH calculations. The calculations also indicate a slightly stronger Ir-Ir bond for L = 3,5-Me2pz than for L= StBu despite the fact that the Ir-Ir bond lengths are identical for both complexes. The reaction of 1 mol of [Ir(Μ-StBu)(CO)2]2 with 2 mol of iodine to yield [Ir(Μ-StBu)(I)2(CO)2]2 was also studied. In this process four Ir-I bonds are formed, and from the corresponding enthalpy of reaction (−186.4±2.7 kJ mol−1) a solution phase Ir-I mean bond dissociation enthalpy in [Ir(Μ-StBu)(I)2(CO)2]2, , was derived. This value is lower than most values reported for octahedral mononuclear Ir111 complexes. New large-scale syntheses of the [Ir(Μ-L)(CO)2]2 complexes, with yields up to 90%, using [Ir(acac)(CO)2] as starting material, are also reported. The X-ray structures of [Ir(Μ-L)(I)(CO)2]2 (L=StBu and 3,5-Me2pz) complexes have been determined. For L=StBu the crystals are monoclinic, space group P2l/c,a=10.741(2) å,b= 11.282(3) å,c=18.308(3) å,Β=96.71(1)‡, andZ=4. Crystals of theΜ-3,5-Me2pz derivative are monoclinic, space group P2l/n,a=14.002(3) å,b= 10.686(1) å,c=15.627(3) å,Β=112.406(8)‡, andZ=4. In both complexes the overall structure can be described as two square-planar pyramids, one around each iridium atom, with the iodine atoms in the apical positions, and the equatorial positions occupied by two CO groups and the two sulfur atoms of the StBu ligands, or two N atoms of the pyrazolyl ligands. In the case of L=StBu the pyramids share a common edge defined by the two bridging sulfur atoms and for L =3,5-Me2pz they are connected through the two N-N bonds of the pyrazolyl ligands. The complexes exhibit short Ir-Ir single bonds of 2.638(1) å for L=StBu and 2.637(1) å for L=3,5-Me2Pz. The oxidative addition of iodine to [Ir(Μ-3,5-Me2pz)(CO)2]2 results in a remarkable compression of 0.608 å in the Ir-Ir separation.

Continuous expansion using an infusion pump was studied in seven patients. Tissue expanders were attached to outpatients under general anesthesia. After a period of 7 days, the skin expansion was initiated with the patient hospitalized. Saline solution (0.9%, 1–3 ml/h) was infused via a gauge needle connected to the expander valve and to the infusion pump. The expansion speed was determined by clinical parameters, such as pain and the expanded tissue viability, until the desired volume was achieved. The total time required for this procedure was 13–18 days. Based on continuous skin expansion, we attempted to test an alternative shorter procedure. This method was well accepted by doctors and patients, and no complications occurred. Although fibrosis was observed, it was not as pronounced as in the outpatients undergoing the conventional expansion treatment. A principal advantage of the continuous expansion method is the increased safety resulting from more effective clinical control and adequate systemic antibiotic therapy. Coupled with on important reduction the expansion time and allowing a faster return of the patients to their activities.

Presents the poem "The Cemetery at Évora," by Paulo Nunes, translated from the Portuguese by James Bogan. First Line: Souls; Last Line: in Purgatory.