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In Latin American cities a great part of the urban environment has grown through self-help processes leading to informal settlements. In the Mexican context, informal settlements are called “colonias populares” which means people’s or popular neighbourhoods. In the late 1960s Turner (1969) argued that popular neighbourhoods should be reconsidered as environments which are socially and culturally responsive to the needs of the inhabitants, as the architecture produced by low-income settlers is based on a system responsive to the changing needs and demands of the users. In these settlements the built environment is the result of the freedom available to inhabitants to take decisions and shape their own environment. This in turn gives place to a myriad of spatial expressions in which culture, identity and popular character are imprinted in both the private and public spaces. This paper explores these issues in the spaces between the dwellings in the public realm.

The purpose of this paper is to study planar sensor geometries for the measurement of film thickness in a viscous oil–water flow. The study is relevant due to there are only a few measurement techniques for oil-water flow and these techniques involve oil with low viscosity (close to the water viscosity). Specifically, some techniques have been used in the studies of annular flow (gas–liquid and liquid–liquid flows), but applications in other flow patterns were not encountered.

Different sensor geometries were numerically simulated to compare their characteristics and choose the best to measure the water film thickness in the oil–water flow through an impedance-based technique. Finite element method was used for resolving the tridimensional electric field over each sensor. The compared characteristics were the penetration depth, the sensitivity, the minimum spatial resolution (high spatial resolution) and the quasi-linear curve.

The best geometry tested has a spatial resolution of 2 × 2 mm, a penetration depth of 700 µm and a quasi-linear response in the measuring range. This geometry was tested by means of conductance and capacitance static experiments. From these experiments, it could be determined that conductance and the capacitance systems are promising for measuring water film thickness in an oil–water flow.

Several measurement techniques such as micro-PIV, planar laser-induced fluorescence and planar conductive or capacitive sensors that are supposed to be adaptable to the liquid–liquid flow have been proposed recently. Micro-PIV and planar-induced fluorescence need transparent pipes and fluids. On the other hand, conductive or capacitive methods have been only applied to low viscosity fluids. In that context, this paper proposes to study a new technique for non-intrusive measurement of the liquid-liquid flow. The main goal is the validation of the new planar sensor as a reference tool for the development of instrumentation for oilfield application.

This paper aims to propose a measurement of the materiality of environmental, social and governance information (ESG) reported by listed companies belonging to sensitive industries in Colombia, Mexico, Brazil, Chile and Argentina. This analysis is carried out from the insights of stakeholder theory, legitimacy theory and institutional theory. The research questions addressed are: What type of information is considered as material by Latin American companies? Does this information respond to the environmental and social issues within the context of Latin American companies and the needs of their stakeholders?

A materiality index is developed from principal component analysis and factor analysis, which are multivariate analysis statistical techniques used in various fields to develop indices. The designed index examines materiality in the sustainability reports of 65 companies for 2017 and 67 companies for 2018. These firms belong to the energy, mining, chemical, construction, construction materials and public services industries in Colombia, Mexico, Chile, Argentina and Brazil.

The results show medium-high materiality indices, mostly in Chilean, Mexican and Colombian companies. In addition, issues such as water management, climate change and occupational health and safety are particularly interesting for companies. For the two years studied and from the perspective of material aspects for the company and its stakeholders, energy, mining and utilities (drinking water and sewage) sectors obtained the highest scores. This shows that the disclosure of ESG information is higher in industries related to the exploitation of natural resources that cause adverse effects on the environment such as extractive industries. Both the analysis presented in this paper and the materiality measurement developed, allow social responsibility managers to have a standard on the level of importance allotted to the different topics disclosed in sustainability reports. Additionally, this study provides a perspective of the material issues recognized by sensitive industries with great environmental impact. Similarly, an analysis of the issues considered material by stakeholders is provided. This allows such issues to be compared, identifying similarities and differences among the issues regarded as material by a company and its stakeholders.

The paper opens the debate is open as to whether the information disclosed response to the needs of stakeholders or whether, on the contrary, the materiality analysis is a process that emerges simply from the interests of the company. These demands for qualitative and field research to complement quantitative studies such as this one to research the stakeholders’ engagement processes in context.

The paper’s purpose a challenge for future research is to strengthen the use of various methodologies that allow knowing the participation processes in the definition of materiality in the ESG information and the companies’ engagement with stakeholders. This stimulates research in the region, which is still in its infancy.

The international literature contains few studies related to the assessment of materiality for sustainability reporting. So this paper contributes proposes measurement of materiality for ESG information.