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This study aims to investigate the effect of bismuth addition (up to 30 Wt%) on the microstructure and electrical conductivity of a commercial lead-free alloy (SAC405) near the solder/substrate soldered joint. The system under study is referred in this work as (SAC405 + xBi)/Cu, as Cu is the selected substrate in which the solder was casted. The electrical resistivity of this system was investigated, considering Bi addition effect on the local microstructure and chemical composition gradients within that zone.

Solder joints between Cu substrate and SAC405 alloy with different levels of Bi were produced. The electrical conductivity along the obtained solder/substrate interface was measured by four-point probe method. The microstructure and chemical compositions were evaluated by scanning electron microscopy/energy dispersive spectroscopy analysis.

Two different electrical resistivity zones were identified within the solder interface copper substrate/solder alloy. At the first zone (from intermetallic compound [IMC] until approximately 100 μm) the increase of the electrical resistivity is gradual from the substrate to the solder side. This is because of the copper substrate diffusion, which established a chemical composition gradient near the IMC layer. At the second zone, electrical resistivity becomes much higher and is mainly dependent on the Bi content of the solder alloy. In both identified zones, electrical resistivity is affected by its microstructure, which is dependent on Cu and Bi content and solidification characteristics.

A detailed characterization of the solder/substrate zone, in terms of electrical conductivity, was done with the definition of two variation zones. With this knowledge, a better definition of processing parameters and in-service soldered electronic devices behavior can be achieved.

Given that the stock market is essential for the venture capitalists to exit through an initial public offering (IPO), this study explores how the laws and regulations governing the capital markets affect the venture capital industry. The paper discusses the impact of US federal state laws and Securities and Exchange Commission (SEC) regulations to the venture capital markets, arguing if the rules and regulatories are burdensome to entrepreneurs and new‐growth businesses. The impact of Sarbanes‐Oxley Act and the future Investment Act on venture capital funds and entrepreneurial companies going public are also discussed. The paper proposes the model of venture capital financing describing the process from fund raising to investment exits, the linkages of the venture capital market to the financial/capital markets and the related capital market laws. The policy implications on SEC regulations essential to the development of venture capital industry are suggested.

Some universities have a commitment to both academic education and sustainable development, and the sustainable development goals can support several sustainable actions that universities may take as principles and attitudes. From this perspective, the purpose of this study is to present environmentally sustainable practices at a federal university in Brazil and to analyze and discuss the potential environmental impacts associated with an environmentally sustainable practice implemented using life cycle assessment (LCA) and its benefits for the university’s decision-makers.

To accomplish that, the study combines a description of environmentally sustainable practices at the 13 campuses of the Universidade Tecnológica Federal do Paraná (UTFPR) in terms of education, water and electricity consumption, waste management and emissions. As a result of this analysis, one campus identified that a high volume of disposable plastic cups were being disposed of, for which the use of reusable plastic cups was introduced. In addition, an LCA study (ISO 14040:2006 and 14044:2006) quantified the benefits of the introduction of said reusable plastic cups.

The results show that the university is working on environmentally sustainable initiatives and policies to become greener. At the same time, using a systematic LCA made it possible to measure that replacing disposable plastic cups for reusable ones reduced waste generation but increased water consumption on the campus. Faced with this, a sensitization was carried out to reduce water consumption. Finally, the current study provides lessons on the environmental performance to universities interested in sustainable practices, fostering perspectives for a better world. The findings of this study encourage organizations to accomplish environmental actions toward greener universities. The study shows that institutions need to be reflective and analytical about how even “greening” measures have impacts, which can be mitigated if necessary.

The sustainable practical implications were reported, and an LCA was conducted to assess potential environmental impacts of reusable plastic cups. It was identified that raw material production is the phase that generates most environmental impacts during the life cycle of the product, along with the consumer use phase, due to the quantity of water used to wash the reusable cups. In addition, the practical contributions of this study are to provide insights to institutions that aim to use environmental actions, i.e. suggestions of sustainable paths toward a greener university.

This is one of the first studies to investigate and discuss sustainable practices at UTFPR/Brazil. The study assessed one of the practices using a scientific technique (LCA) to assess the impacts of reusable plastic cups distributed to the students of one of the 13 campuses. Although there are other studies on LCA in the literature, the value of this study lies in expanding what has already been experienced/found on the use of LCA to assess environmental practices in university campuses.

This paper aims to study the dynamics of bitcoin prices in Brazil, a large emerging economy with an unregulated bitcoin market.

First, this study tests if the Law of One Price (LOOP) is valid for bitcoin prices in Brazil, conducting tests with data from three Brazilian exchanges. Next, this study documents bitcoin price dynamics in the short run by studying the price discovery mechanism in these exchanges. This study uses Information Share and Component Share, combining the two measures to obtain an Information Leadership Share (ILS) measure.

This study finds a common trend within bitcoin prices among a set of exchanges, with cointegration tests between the price series indicating that LOOP is valid in Brazilian markets in the long run. ILS indicated that, for closing prices, the most liquid exchange (Foxbit) leads discovery, whereas the least liquid (Local Bitcoin) lags, with Mercado Bitcoin in the middle both in terms of discovery and liquidity. Finally, this study provides evidence that the price variation in the market that leads price discovery can be used to construct an arbitrage in another exchange.

This research brings the first evidence of a price discovery mechanism for exchanges in Brazilian Reais. Although LOOP is valid in the long run, price leadership in bitcoin markets potentially create arbitrage opportunities in the short run. This study contributes to the growing literature of bitcoin prices with novel evidence from a large emerging economy.

This study aimed to the attributes, consequences and personal values that motivate the behavior of consumers of fruits and vegetables (FV) at local markets and how these elements are associated with food safety.

This is a qualitative research that used the laddering in-depth interview technique for data collection. Fifty interviews were conducted with consumers from Minas Gerais, Brazil. From the codification of the interview content, a hierarchical value map was constructed, showing the relationships between the attributes, consequences and values involved in the consumers’ purchasing decision.

Consumers value characteristics related to the origin of the product and the way it is produced and marketed. They seek particular benefits – such as satisfaction with the purchase, care for their health/well-being and safety when consuming food – and social benefits, such as the possibility of contributing to the local economy. Issues related to hygiene, organization, exposure and handling of products were some of the concerns reported by respondents with regard to food safety.

It is worth highlighting the application of the laddering technique itself. Analyzing the predictive validity of the method, there is a propensity for biases linked to possible interference by the researcher, especially in the coding stage of the elements.

This study can be used by producers, marketing professionals and public policymakers to promote FV sold at local markets and to encourage the improvement of food safety practices.

The research points to five consumer segments according to the different motivations that guide their purchase behavior for local FV. In addition, a focus is given to food safety, revealing its importance in the investigated context.

The purpose of this paper was to identify and describe the personal values that motivate and guide the cognitive structure of Brazilian wine consumers from the viewpoint of the means-end chain theory.

In this qualitative descriptive study, 40 in-depth laddering interviews were conducted in the state of Minas Gerais, Brazil, which were transcribed and codified from the attributes, consequences, and values that emerged in the discourse of the wine consumers. The codes were subsequently graded – in accordance with the level of abstraction – and inserted into the LadderUx® software to generate the implication matrix and the hierarchical value map. The interpretation of the cognitive structure of the wine consumers occurred descriptively.

Common aspects regarding knowledge of the product linked to the ritual of wine consumption were identified among consumers. The psychological factors basically describe the social aspects that are pertinent to the drink’s consumption and to aspects focused on the personal training that leads to consumption satisfaction. Both converge in the search for more knowledge about the world of wine. From this cognitive basis, the existence of the instrumental values of hedonism, benevolence/care, stimulation and achievement could be seen, as well as the terminal values of joy and happiness.

This study presents the cognitive structure of the Brazilian consumers of wine. This result allows some insights in an initial perspective for the development of strategies, based on the factors that motivate the purchase of the drink, thus attracting new consumers to this emerging market.

The purpose of this paper is to analyze consumer behavior based on the structures of attributes, consequences, and values identified by consumers of beverages obtained from capsules. Consumers of the brands Nescafé Dolce Gusto and Nespresso capsule-based beverages were selected, and comparatively analyzed to understand the possible differences perceived by the consumers of each brand.

Based on a soft laddering technique, 27 in-depth interviews were carried out among the users of Nespresso and Dolce Gusto. This technique allowed differentiating the attributes of each brand, as well as defining common/cumulative elements.

Individual values of achievement and personal pleasure, mainly reached through better living standards, were dominant for all consumers. Dominant chain analysis results showed the perceptions of consumers were different for each brand. Generally, both brands’ consumers seek quality and practicality. However, Dolce Gusto delivers a product perceived as having more functional benefits, thus serving consumers seeking more variety when it comes to different types of beverages. On the other hand, Nespresso serves a more selective niche market, whose consumers rather value brand quality and reliability.

The characteristics and product specifications show similarities with food consumption trends, which justify the growth of this market in recent years. Therefore, strategies and the consumers’ demand for the capsule market show a promising trend on the coffee and drinks market in Brazil, deserving special attention from both companies and producers.

This paper examines the impact of extreme rainfall shocks on the performance in test scores of students living near at-risk urban areas in Brazil.

To identify the causal effect, we consider the exogenous variation of rainfall at the municipal level conditioned on the distance from the school to risk areas and the rainfall intensity in the school months.

The results suggest that extreme precipitation shocks, defined as a shock of at least three months of high-intensity rainfall, have an adverse impact on both math and language performance. Through a heterogeneous effects analysis, we find that the impact varies by student gender, with girls being more affected. In addition, among students who study near at-risk areas, those with better previous school performance and higher socioeconomic status are more negatively affected.

Our results suggest that extreme weather events can increase the differences in human capital accumulation between the population living near risk areas and those living more distant from these areas.

Given the importance of growth-oriented entrepreneurship in the context of economic development and the need to understand how rural communities can be developed, the purpose of this research paper is to determine how the drivers of growth expectations differ between urban and rural settings.

The methodology is threefold: firstly, a descriptive analysis with non-parametric testing is conducted; then pooled regression model is used to analyse the predictors of growth expectations in both contexts, and finally, coarsened exact matching is used to identify possible self-selection bias.

In contrast to mainstream entrepreneurship theory, it is found that entrepreneurs’ intrinsic knowledge, skills and abilities are not significant in the rural-specific model. The only exception is entrepreneurs’ educational level, the importance of which is emphasised as a pivotal factor in increasing high-growth ventures in rural communities. Additionally, when self-selection is eliminated, rurality worsens growth intentions.

There is evidence that some growth-oriented entrepreneurs self-select into rural communities. Because the high-growth entrepreneurial dynamics in rural areas are unique, public policies should target purpose-driven entrepreneurial education. This includes encouraging “lifestyle entrepreneurship” (e.g. retirees returning to rural areas to become entrepreneurs), preventing entrepreneurial brain drain in rural areas and attracting highly educated urban entrepreneurs to exploit opportunities in rural areas.

This research attempts to contribute to the ongoing debate regarding the factors that drive high-growth entrepreneurs in rural areas by analysing rural entrepreneurs in the high-growth context of a developing economy. The focus is on Chile – a country that is rarely investigated compared to the USA or Europe – to extend the literature on high-growth ventures and entrepreneurial ecosystems.

This paper aims to present a computational framework to generate numeric enrichment functions for two-dimensional problems dealing with single/multiple local phenomenon/phenomena. The two-scale generalized/extended finite element method (G/XFEM) approach used here is based on the solution decomposition, having global- and local-scale components. This strategy allows the use of a coarse mesh even when the problem produces complex local phenomena. For this purpose, local problems can be defined where these local phenomena are observed and are solved separately by using fine meshes. The results of the local problems are used to enrich the global one improving the approximate solution.

The implementation of the two-scale G/XFEM formulation follows the object-oriented approach presented by the authors in a previous work, where it is possible to combine different kinds of elements and analyses models with the partition of unity enrichment scheme. Beside the extension of the G/XFEM implementation to enclose the global–local strategy, the imposition of different boundary conditions is also generalized.

The generalization done for boundary conditions is very important, as the global–local approach relies on the boundary information transferring process between the two scales of the analysis. The flexibility for the numerical analysis of the proposed framework is illustrated by several examples. Different analysis models, element formulations and enrichment functions are used, and the accuracy, robustness and computational efficiency are demonstrated.

This work shows a generalize imposition of different boundary conditions for global–local G/XFEM analysis through an object-oriented implementation. This generalization is very important, as the global–local approach relies on the boundary information transferring process between the two scales of the analysis. Also, solving multiple local problems simultaneously and solving plate problems using global–local G/XFEM are other contributions of this work.