*Perspective* **Implementing SDGs to a Sustainable Rural Village Development from Community Empowerment: Linking Energy, Education, Innovation, and Research**

**Isabel del Arco 1,\* , Anabel Ramos-Pla <sup>1</sup> , Gabriel Zsembinszki <sup>2</sup> , Alvaro de Gracia <sup>2</sup> and Luisa F. Cabeza 2,\***


**Abstract:** Rural depopulation is a worldwide fact and has a domino effect on medium and small cities, which act as a nucleus of reference for small towns. Moreover, the United Nations (UN) stressed that disparities between rural and urban areas are pronounced and still growing over time. Globally, people in rural areas lack access to modern energy services, which affects productivity, educational and health services, exacerbating poverty, among other things. Given this reality, the following research questions arise: how can we act to reverse this reality? Are there examples of transformation in rural contexts where community empowerment is a key strategy? This paper aims at describing the transformation process of a small rural municipality towards a sustainable development, in parallel to the activation of the local productivity that helps to eliminate the effects of rural depopulation. Therefore, the project ALMIA was established as an example of a sustainable village that is Almatret (Catalonia-Spain). The backbone of such project is the commitment to community empowerment, where the main results are the generation of networks with experts and researchers to help the municipality's energy transition, the involvement of the local administration, the commitment to technological development, as well as the socio-community development. Moreover, the activities developed within the project ALMIA are aligned with the UNs Sustainable Development Goals, alignment that is analyzed in detail. Thus, this paper aims to further highlight existing sustainable development practices related to community empowerment in order to promote similar practices.

**Keywords:** community empowerment; energy transition; rural depopulation; sustainable development; Sustainable Development Goals (SDGs)

#### **1. Introduction**

In 2015, the United Nations (UN) and its member states adopted by resolution the 2030 Agenda for Sustainable Development [1] with the overall goal of providing a path to peace and prosperity. This agenda ensures that all countries develop in relation to economic growth. At the same time, it aims to improve health and education, reducing inequality and tackling climate change.

All of this is implemented in 17 Sustainable Development Goals (SDGs) that include targets and actions to achieve this ambitious overarching goal.

These objectives are based on a modern conception of human development that gives relevance to health and education, overcoming the old conception that considered development as "a process of continuous economic growth, which ensures a lasting surplus of all kinds of goods, which can be used to meet human needs and enhance greater wellbeing" [2]. Thus understood, human development seeks the welfare and quality of life of people.

We speak of Sustainable Development because the person is at the center of all policies and efforts to improve conditions in each social context. To achieve this, three key

**Citation:** del Arco, I.; Ramos-Pla, A.; Zsembinszki, G.; de Gracia, A.; Cabeza, L.F. Implementing SDGs to a Sustainable Rural Village Development from Community Empowerment: Linking Energy, Education, Innovation, and Research. *Sustainability* **2021**, *13*, 12946. https:// doi.org/10.3390/su132312946

Academic Editors: Margarita Martinez-Nuñez, Mª Pilar Latorre-Martínez and Marc A. Rosen

Received: 19 August 2021 Accepted: 18 November 2021 Published: 23 November 2021

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

principles must be taken into account: (i) the promotion of remote human and socially equitable development for all humanity based on inclusion, (ii) the guidance of economic development at the service of human development, and finally, (iii) the promotion of responsible use of the planet's natural resources [3].

The 17 SDGs are inter-related and mark inclusion, security, production, and consumption as core issues for the sustainable development of human settlements (cities, towns and villages) [4]. The creation of viable human settlements becomes a clear indicator of socially and economically sustainable development.

This article focuses on rural settlements and how the SDGs can be applied to these currently vulnerable populations. It is interesting to know how we can act in these populations to promote their sustainable development by basing their transformation on community empowerment as a key strategy.

Thus, the aim of this paper is to describe the transformation process of a rural municipality towards sustainable development in parallel with the activation of local productivity that helps to reduce or eliminate, among others, the effects of depopulation. In order to do so, the global situation of rural settlements, the problems they face and the consequences that arise from them will be contextualized. Subsequently, it will be argued that it is important to focus on these settlements in order to make the development of the 2030 Agenda globally effective.

The municipality of Almatret is presented as a current example of a positive and sustainable village and the ALMIA project as a strategic plan designed for the transformation of the municipality. It is important to understand how the ALMIA project is aligned with the global implementation of the 17 SDGs, and specifically with some of them.

#### **2. Towards a Sustainable Village**

The dramatic rapid growth of cities has been a constant during the last years. It is estimated that by 2030, almost 60% of the world population will live in urban areas. This strong expansion will occur in 95% of developing countries.

This has generated problems such as high levels of exclusion and citizen insecurity, pressure on water supply, waste generation and, in short, uncontrolled production and over-consumption. These problems are even expected to become even more accentuated in the coming years.

These are the questions that SDGs eleven and twelve of the 2030 Agenda seek to address. Both goals propose that cities and human settlements in general should be inclusive, safe, resilient, and sustainable by promoting controlled production and moderate consumption.

On the other hand, rural depopulation is a fact worldwide and has a domino effect also for medium and small cities that act as a nucleus of reference for small towns [2]. A reduction of inhabitants in the region means that the supply of services, leisure, health, or education becomes meaningless, and with them, the corresponding jobs disappear. All this generates a chain effect that leads the population to seek opportunities in large cities [5]. These large concentrations of population can become unviable and unsustainable.

It is essential to have better and more sustainable cities, but it is also important to have an impact on rural populations, which are generally limited in terms of roads, electricity supply, telecommunications and other types of infrastructure that are of key importance for their development and growth. All these factors mean that the rural population receives more limited educational, health and social services, which has a negative impact on their well-being.

Let us remember that agriculture is still the main economic activity in rural territories, and despite being an activity with a high potential to support environmentally sustainable growth, there is evidence that the current form of food production is one of the main drivers of climate change [6,7]. In addition, the economic income it generates is low, and gender inequality is exclusionary [8,9].

The 2030 Agenda recognizes that rural settlements are determinant for the achievement of its goals and that public policies cannot forget that development also involves rural

areas. According to UN-Habitat (2006), sustainable human settlements involve providing adequate shelter for all inhabitants, and this involves improving management by:


SDG two devotes specific attention to rural areas by proposing increased investment in infrastructure, agricultural research and extension services, technological development and plant and livestock gene banks. This is the only way to reduce inequality between rural and urban areas.

We must prevent the population of rural settlements from lacking access to modern energy services because it affects productivity, educational services and even the health of the population, aggravating poverty [10].

Recently, new approaches to sustainable rural development have emerged, emphasizing the nexus between energy, health, education, water, food, gender, and economic growth.

The focus is on inclusive and sustainable development. It is about increasing productivity, creating jobs and generating income. All of this is based on social inclusion, gender equality and decent employment for young people. Development must focus on the creation of added value through the application of research and innovation (R&D&I).

On the other hand, there is a growing concern about economic and environmental development, intensified by the global energy, food and financial crises, and the COVID-19 pandemic. All this translates to a continuous warning about the transgression of planetary or ecological limits, reflected in climate change. The green economy is the proposed alternative to catalyse new national policies in support of sustainable development.

Access to affordable, reliable, sustainable, and modern energy for all would create new job opportunities, empowerment of women and youth, better education and health, and ultimately more sustainable settlements using a powerful climate change strategy.

Education is an integral element of sustainable development, not only ensuring quality, inclusive, and equitable education for children, but also including lifelong learning opportunities. Education can build sustainable societies by actively integrating citizens' education into sustainable development.

Isolation, lack of infrastructure, scarce diversification and access to services can affect the health of the rural population.

Finally, we must focus on sustainable consumption and production as key factors for the proper management of natural resources. The rational use of aquifers, the reduction of waste production and its recyclability and reuse are part of what is being called circular economy, which affects sustainable development.

At this point, is it possible to reverse reality in order to achieve sustainable development? How can we act in rural settlements to promote their development? Are there examples of transformation of rural contexts where community empowerment is a key strategy?

There are some examples of sustainable cities and towns that are making the achievement of the SDGs possible: from the Middle East (Education City to Qatar and Masdar City in Abu Dhabi), the Far East (Dongtan Institute in China, Nova Songdo City in Korea South), Ruhr, Feldheim, and Freiburg (Germany), Vancouver (Canada), Brighton (United Kingdom), Genk (Belgium), Stockholm (Sweden) [11–14]. Considering the number of existing large cities (400) and mega cities (23) [2], it is necessary to rethink their sustainability. There are also energy transition initiatives towards sustainability in small towns such as in Poland (Biskupiec, Nowe Miasto Lubawaskie, Nowy Dwór Gdánski, Górowo Ilaweckie, Goldap or Ryn), Scandinavia (Danishh Svendborg, Norwegian Skotterutd, or Swedish Falkoping), and Germany (Marihn, Meldorf, or Penzlin) [15]. In Spain, the island of El

Hierro has become, through renewable energies, the first self-sufficient island in terms of energy [16]. These initiatives seek to achieve local sustainable development [17,18].

An example of interest is the case of "East Village at Knutsfod" (EVK) [19], located 1.5 km from the central business district of Fremantle (Western Australia). The project aims to create semi-detached houses that incorporate solar energy storage through photovoltaic solar systems (designed to produce more energy than is consumed in the domestic environment), a battery deposit for charging electric vehicles and integration of the urban water management (through stormwater infiltration, alternative urban supplies, and biophilic urban designs) to reduce dependence on centralized water sources. With this, it is intended that the town ends up using 100% renewable energy for daily consumption [20].

In this context, the municipality of Almatret has developed the project ALMIA, with the aim of increasing its sustainable development by becoming a net positive energy village. This document presents the process that the village is undertaking and how it links all its actions (past, present, and future) to the SDGs. The objective of this article is to present the ALMIA project and the processes of transformation into a sustainable development village.

#### **3. Almatret, an Example of a Sustainable Village**

#### *3.1. Description of the Municipality*

Almatret is a small village located in the southwest of Catalonia, Spain (Figure 1) [21], next to the river Ebro in the limit with Aragon. Today, it has around 300 inhabitants in a surface area of 56.83 km<sup>2</sup> . Almatret has a very rich history because Iberians, Romans, and Arabs lived in its area. The village is considered to be founded in 1301.

**Figure 1.** Almatret map (Google Maps, 2021) [21].

Today, Almatret's main industry is agriculture, mainly olive and almond, and livestock industry, mainly pork industry. During the XIX century, Almatret had a lot of coal mines, when the population was as high as 2000 inhabitants.

Almatret is classified within the Continental Mediterranean climate, Bsk in the Köppen-Geiger climate classification [22]. Therefore, the town climate is characterized by having a very marked seasonality (in distribution of temperature and rainfall). In other words, summers are hot and dry, and winters are very cold [23]. Its agriculture is dry land where the almond tree occupies 41% of the cultivated land (43% of the municipal total). In addition, olive and barley are grown. Industrial activity is concentrated in the production and elaboration of olive oil. During the 20th century, there was great economic activity promoted by the exploitation of small deposits of lignite, although, at the end of the century, it went into decline.

During this time of mining splendour, there was an expansion of Almatret with the construction of a large part of the town houses, as also happened in the Apuseni (Romania) [24]. There was an increase in the population that rapidly decreased due to the abandonment of this activity with the emigration of its inhabitants to nearby centres with more services. At present, Almatret is a municipality of less than 350 inhabitants.

Its geographical location makes it ideal for the installation of wind farms. In 2003, more than 25 turbines with a nominal power of more than 50,000 kW [25] were installed, to which the last project, the Vencills wind farm, consisting of only four mills, but of a size and a higher power (24 MW), was added. Almatret is located in a geographic pool of energy production, a few kilometers from the Ribaroja reservoir and the Maquinenza thermal power plant. Moreover, from the Asco nuclear power plant and also the settlement of various solar parks, a landscape conformed oriented to the production of energy, from a past with lignite mines to the present with the different mentioned alternatives sources.

#### *3.2. The Project ALMIA*

Around 2010, the municipality of Almatret decided to initiate a new project with the aim of reversing the loss of population, jobs, and quality of life in the municipality. This led to the creation of the ALMIA project, which develops a series of actions based on three basic principles:


Therefore, the actions proposed in the ALMIA Project are developed as follows:


and domestic hot water applications. Moreover, a latent heat thermal energy storage system of 100 kWh of capacity is used to expand the ORC 4 h after solar availability. The system relies on the use of heat pipes to transfer the heat from oil to PCM and the way back.

**Figure 2.** Fresnel solar field and youth hostel building.

Shortly after, Almatret started its participation as full partner in the European funded project HYBUILD [29], again hosting one of the three demonstration sites. Within HY-BUILD, two innovative hybrid storage concepts are developed and tested: one for Mediterranean climate, focused mainly on meeting the cooling demand in residential buildings, and one for Continental climate, for which the main focus is to provide heating and domestic hot water in residential buildings. Innovative components are integrated in both systems, such as a high-density latent storage, a reversible vapor compression heat pump, a DC bus connected with PV panels to run the heat pump in DC. Moreover, the Mediterranean climate system also contains a compact sorption module and a field of Fresnel solar collectors. Other than the thermal energy storage components, an electric storage is also used to store the surplus of electricity production of the PV system. An advanced control and building energy management system (BEMS) is also implemented in the systems to ensure a proper end efficient operation. The demonstration site in Almatret is a single-family residential building (Figure 3) where the Mediterranean climate system is implemented and tested for future assessment and validation.

**Figure 3.** Residential building where the HYBUILD Mediterranean system is implemented.





The vision of renewable energies as an integrative alternative to socio-economic and environmental challenges, together with the commitment to open innovation where citizens are participants in the advances in research in energy systems, is the commitment of the proposal of the Energy Interpretation Center (EIC) and the ALMIA museum that is being developed in Almatret. This current of openness about technological scientific advances coincides with the establishment of participation mechanisms in science and innovation that allow citizens to have information and be part of the innovation system. In addition, these initiatives seek to influence the economic and social revitalization of a territory that in recent decades has been immersed in unprecedented depopulation.

The objectives of EIC are, among others:


This interpretation center is based on the inclusion of contextualization elements of the existing active energy facilities such as the wind farm and photovoltaic solar installation, as well as the recovery of the territory heritage. It will also have a museum area with exhibition, educational, and research programs that allow the carrying out of education, communication, and heritage preservation activities. The creation of a research program for the generation of integrated solutions for renewable energy and energy efficiency and the possible application of these solutions in the municipality will allow the transfer of knowledge in this area and the participation of citizens in the innovation process. The technological facilities that currently exist in Almatret are the best starting point for the visitor to find inspiration in the curiosity for science and technology, in formulating questions about the impact on their past and present life, thus stimulating reflection and knowledge. EIC, in short, is an open and public space dedicated to scientific and technical knowledge, based on rigor, credibility, accessibility and understandability.

The pedagogical paradigm that frames the ALMIA proposal focuses on the empowerment of citizens [30,31] as active actors of the project, generating a committed implication and running with responsibility. This citizen empowerment begins with the generation of a promoter group that helps to start this community process. The promoting group is made up of specialists and experts in the field (teachers and researchers) as well as technicians from the local administration. This promoter group will guide the community diagnosis phase, prioritizing the intervention strategies, planning the actions that will be put into practice to finally evaluate the process and the impact. It is very important that the inhabitants of Almatret know about the project and are involved in all phases of development. The promoter group encourages this participation, but at the same time it must establish a network of entities and organizations that help to disseminate, implement and consolidate the project. ALMIA is planted from its socio-educational aspect as an example of community development with the involvement of citizens. At present, educational activities for schoolchildren have already been generated, educational material has been generated and different practical workshops have been piloted. All this begins an educational and scientific tourism [32] oriented to the interpretation of the different sources of energy that exist in the municipality.

All these activities created the first quality jobs, one for an engineer or similar, to be able to manage all the new systems installed in the village, and a second one to lead the educational activities and the relation with schools.

#### **4. Consistency between the SDGs and ALMIA**

The Action Plan for the Implementation of the 2030 Agenda in Spain [33] clearly states that "it is not possible to achieve the SDGs by leaving rural areas and their inhabitants behind". ALMIA is presented as a strategic project which develops a series of specific actions within the framework of SDG deployment, which are specified in Table 1.


**Table 1.** Summary of the relationship between the ALMIA project and the SDGs.

Rural development involves empowering the rural population and formulating policies that generate synergies between institutions, seeking common objectives to advance sustainable development, ensure quality of life and a better balance in population distribution [34].

When rural people are empowered, they are able to participate, decide, negotiate, influence and control so that they can strengthen their family and productive environments in the face of the invisibility imposed by the current socio-economic evolution.

Distributed and committed leadership is important, as in the case of the ALMIA project, where the city council assumed this role. It also seeks complicity with external agents such as the University of Lleida and the Provincial Council. In short, the role of the local administration is fundamental as an agent to lead the change and transition in the municipality towards a type of circular and sustainable economy.

In line with SDG #7 and SDG #13, a clear commitment has been made to the production of renewable energy, taking advantage of available local resources, in this case its privileged orographic situation. In addition, ALMIA represents a step forward in the research, development and application of new energy techniques that lead us to zero consumption of finite resources that are not very respectable with the environment. From this scientific, engineering and research dimension, ALMIA responds to SDG two and SDG nine with three projects funded by the EU:


Aligned with SDG 11 and from this scientific and technological dimension, different proposals are being projected in the municipality to transform buildings into sustainable buildings with an important integration of renewable energies, promoting the consumption of this type of energy: rural buildings under self-consumption, means of transport, systems heating of homes, etc. It would be a balanced use of different renewable energies that are generated by the municipality, both those that have a greater technological maturity (wind and photovoltaic) and those that are more manageable (solar, thermoelectric, biomass, among others), always taking advantage of local resources and minimizing the environmental impact and in the territory.

It is also necessary to highlight the socio-educational dimension of this project. The aim is to turn the EIC into a pole of attraction for educational centres to influence the education of young people. To this end, activities are planned that involve the municipality, generate jobs and help disseminate scientific knowledge, laying the foundations for raising awareness and involving young people in the implementation of the 2030 Agenda and the ESD 2030.

The EIC, aligned with SDG four, becomes a Learning Camp open to students from different educational stages and levels, and to the general public. The added value is to learn in situ about energy production, transport, storage, energy transition, and responsible energy consumption.

The museum part of the project adds value to the scientific and technological dimension of ALMIA. The same inhabitants will help to create a local inventory of heritage resources (natural and cultural, tangible and intangible).

This is aligned with SDG eight where the rural nucleus is transformed into a good to know and to protect. To all this, other additions are:


#### **5. Discussion and Conclusions**

The UN objectives cannot be achieved only with top-down actions. Bottom-up initiatives, such as the one presented and analyzed in the paper, are key and necessary to reach these challenges. Almatret is a clear example of a small village fighting to overcome

depopulation and doing a good use of local resources in a sustainable way [35]. The ALMIA project is a clear example of a strategic organization based on community empowerment that promotes participation by fostering a sense of community and belonging to the group [36]. It is based on available resources, with a broad vision of the concept of resources beyond the economic, also taking into account personal capital and the possibilities of the context/environment. It is necessary to mobilize all the opportunities and strengths of the rural context to promote transformations.

AlMIA promotes networking, not only with surrounding municipalities and institutions, but also with scientific experts from the University of Lleida. This networking helps to share information, resources, processes, consolidates the commitment between actors, etc., increasing the chances of success, and all this is from the distributed leadership exercised by the municipal council, in decision making and in the development of the work, which provides greater flexibility and agility in all processes and much more efficient results [26].

The commitment to clean energy in Almatret is not limited to an economic issue but goes beyond that and is committed to the production and energy transition of the municipality itself. The promotion of the rehabilitation of buildings towards the concept of passive houses, the installation of charging points to encourage electric transport and facilitating access to sustainable, reliable and modern energy are key aspects to achieve the goal of turning this town into a positive-energy and zero-carbon village [37]. This is an approximation to what some authors propose as a leap towards a smart village based on sustainable energy with the possibility of disconnecting from the grid and producing more energy than it consumes.

Sustainable development has also been promoted through research and innovation (through European projects such as Innova MicroSolar and HYBUILD) and the improvement of infrastructures. Networking with experts who provide technical advice helps to eliminate the isolation of rural areas and to bring innovative proposals closer together. Citizens are involved in scientific initiatives and raise the problems of the municipality to find solutions. This is an effective way of implementing the SDGs, with the collaboration of citizen science, which helps to strengthen research designs in the field of renewable energies, taking into account the interests and needs of citizens [38–40].

Finally, in this effort to effectively implement the SDGs, focusing on energy and linking research, innovation and education, ALMIA proposes the creation of the EIC as a strategy to address education in renewable energy and energy efficiency, contributing to formal and non-formal participatory science education and open to all audiences, although preferably to the student population [41–45].

The idea is to influence social transformation by generating knowledge among the population that will help to involve society in the promotion of Agenda 2030 and ESD 2030. This is part of the strategy known as education for global citizenship, which seeks to involve civil society in the transformation, and this is only possible if it is educated in the commitment to the wellbeing and quality of universal life.

Influencing the education of future generations to participate and take active roles, locally but also globally, makes them proactive contributors in responding to the challenges of today's society [46,47].

Currently, the ALMIA project is beginning to bear fruit: there is increased tourism to the village with organized academic visits (more than 250 in the last year and 1500 are expected for next year). Direct jobs have been created to revitalize the EIC and indirect jobs (opening of restaurants). The production, transport, efficient consumption and storage of clean energy has become a catalytic issue, contributing to the effective implementation of the SDGs in this rural village.

The ALMIA project presents specific limitations and barriers. It is difficult to reverse the isolation and depopulation of the municipality when it is a marked trend of the last decades. Depopulation has led to the suppression of services: schools, health services, commercial infrastructures.

The low public investment by the regional and state administration hinders the consolidation of the project, which is based on local funding and the voluntary work of the project's generators (municipal managers, university professors and researchers). The leadership of the local administration is important, but changes of government after elections can slow down the implementation of ALMIA.

The environment, the investment in renewable energies, and the enthusiasm of the population of the municipality support the project, although the lack of young people involved, because of an aging population, can endanger the continuity of ALMIA over time.

**Author Contributions:** Conceptualization, L.F.C. and I.d.A.; methodology, L.F.C. and I.d.A.; investigation, L.F.C., I.d.A., A.R.-P., A.d.G. and G.Z.; resources, L.F.C.; data curation, L.F.C.; writing original draft preparation, L.F.C. and A.R.-P.; writing—review and editing, I.d.A., A.d.G. and G.Z.; visualization, A.d.G. and G.Z.; supervision, L.F.C. and I.d.A.; project administration, L.F.C. and I.d.A.; funding acquisition, L.F.C. and I.d.A. All authors have read and agreed to the published version of the manuscript.

**Funding:** This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 768824 and under the grant agreement No 723596. This work is partially supported by ICREA under the ICREA Academia programme.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable..

**Data Availability Statement:** Data available under request to the correspondence authors.

**Acknowledgments:** The authors would like to thank the Catalan Government for the quality accreditation given to their research group (2017 SGR 1537). GREiA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. The authors would like to thank the Almatret municipality for their involvement in this challenging project.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **Abbreviations**

SDGs Sustainable Development Goals. There are 17 Sustainable Development Goals (SDGs), which are an urgent call for action by all countries (developed and developing) in a global partnership ESD Education for Sustainable Development. This action empowers learners of all ages with the knowledge, skills, values and attitudes to address the interconnected global, environmental degradation, loss of biodiversity, poverty and inequality BEMS Building Energy Management System. It offers monitoring, metering, as well as submetering, functions which help collect energy data, giving property managers and owners a comprehensive insight on building's energy usage ALMIA Name of the project that aims at increasing the sustainable development of the village of Almatret by means of becoming a positive energy village. The acronym comes from joining the name of the village (Almatret) with the word energy in Catalan (energia), i.e., ALMatret+energIA EIC Energy Interpretation Center DC Direct Current

#### **References**


**Edward B. Barbier \* and Joanne C. Burgess**

Department of Economics, Colorado State University, Fort Collins, CO 80523-1771, USA; jo.barbier@colostate.edu **\*** Correspondence: edward.barbier@colostate.edu; Tel.: +1-9-70-491-6324

**Abstract:** Whether institutional quality and governance help or hinder progress towards the 17 Sustainable Development Goals (SDGs) of UN Agenda 2030 is an important issue to consider. These fundamental social structures are generally under-represented among the SDGs, but institutional quality and governance often have an important role in supporting or constraining efforts to achieve sustainable development. We compare estimates of the changes in net welfare that reflect progress towards the 17 SDGs over 2000–2018 with two institutional quality and governance indicators over the same period. We do this at the world level, for the group of low-income countries and for nine representative developing countries. We utilize the Worldwide Governance Indicators and OECD's Country Risk Classification as our two institutional quality and governance measures. We find that SDG welfare gains are somewhat correlated with institutional quality and highly correlated with lower country risk. These results suggest that good governance and institutional effectiveness are associated with long-run development and sustainability success. Long-term progress towards the SDGs may hinge on improved institutional quality and reduced country risk.


**Citation:** Barbier, E.B.; Burgess, J.C. Institutional Quality, Governance and Progress towards the SDGs. *Sustainability* **2021**, *13*, 11798. https:// doi.org/10.3390/su132111798

Academic Editors: Margarita Martinez-Nuñez, Mª Pilar Latorre-Martínez and Antonio Boggia

Received: 1 September 2021 Accepted: 21 October 2021 Published: 26 October 2021

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

**Keywords:** country risk; developing economies; governance; institutional quality; low-income countries; SDGs; sustainable development

#### **1. Introduction**

Since the early 1990s, a large empirical literature in economics has established a persuasive link between institutions and long-run economic development [1–12]. Institutional quality is a broad concept that refers to law, individual rights and the provision of government regulation and services. A breakdown in these attributes undermines and weakens the institutional framework supporting economic development. Although the causality of the relationship between strong institutions and long-run economic development may be in doubt [2], the possibility that economic progress, institutional quality and good governance go hand-in-hand is rarely questioned. Recent evidence also shows that more effective institutions and governance are essential to reducing extreme poverty and achieving other development goals that are important to low and middle-income economies [13].

This raises an important question. As the world shifts its focus towards making development more "sustainable", as reflected in the UN's Agenda 2030, are weak institutions and governance inhibiting long-term progress towards sustainability, especially in poorer economies? For example, does a break down in factors such as the effective rule of law, an uncertain business climate, insecure property rights and the presence of social norms that are not conducive to market-based trade and transactions, constrain sustainable development? [10,11].

In 2015, the General Assembly of the United Nations (UN) formally adopted "The 2030 Agenda for Sustainable Development". This provides a framework for "peace and prosperity for people and the planet, now and into the future" [14]. The centerpiece of Agenda 2030 are the 17 Sustainable Development Goals (SDGs). As Jeffrey Sachs emphasized, the SDGs "aim for a combination of economic development, environmental sustainability and social inclusion" [15], p. 2206. Attaining the SDGs can be viewed as sustainable development in its broadest sense, through achieving progress across economic, social and environmental systems simultaneously [16–18]. This approach has been called the systems approach to sustainability, and is attributed to Barbier (1987) [19]. The 17 SDGs can be attributed to the economic, social and environmental systems. For example SDG 1: No Poverty, and SDG 8 Good Jobs and Economic Growth are goals within the economic system. SDG 13 Climate Action and SDG 14 Life below Water are environmental system goals. Within the social system goals, SDG 10 Reduced Inequality and SDG 16 Peace, Justice and Institutions reside [16–18].

The systems approach to sustainability contrasts with the economists' capital approach to sustainability [20]. The capital approach to sustainability treats nature as a form of capital. In order to ensure that future generations have at least the same economic opportunities, and thus the same economic welfare, as the present generation, the capital approach to sustainability entails managing and enhancing a portfolio of assets. This portfolio of assets comprise the total capital stock, which consists of physical, human and natural capital. In addition to maintaining or enhancing the total stock of capital, any essential natural capital needs to be kept "intact" due to imperfect substitution, irreversible losses and uncertainty over values [20].

Within the SDGs systems approach to sustainability, institutional attributes seem to be under-represented in the 17 SDGs of Agenda 2030. Only one of the goals, SDG 16 Peace, Justice and Strong Institutions, includes these attributes, and they are narrowly defined. For example, the 23 indicators currently proposed by the UN to track progress towards SDG 16 focus mainly on reducing violence, conflict and political instability rather than on broader measures of institutional quality and governance [21]. Although peace and political stability are essential to sustainable development, strong institutions also imply creating the economy-wide business and market conditions to sustain economic progress and development through promoting effective government, the rule of law, reducing unnecessary regulation, greater accountability and minimizing corruption and risk. As summarized by the World Bank: "Strong institutions and conducive business climates can set the stage for vigorous growth. Institutions can promote forms of economic activity that are associated with greater economic complexity and higher productivity growth by encouraging human capital accumulation and innovative activities." [22], p. 40.

In this article, we examine further whether better institutional quality and a more conducive business climate can help or hinder advancement towards the 17 Sustainable Development Goals (SDGs) of UN Agenda 2030. To assess attainment of these goals, we make use of our existing analysis of the net welfare changes of advancement towards the 17 SDGs over the period 2000–2018. We do this at the world level, for the group of low-income countries and for nine representative developing countries [17]. For the same sets of countries, we contrast and compare our estimates of net welfare gains or losses with two institutional quality and governance indicators over the same period.

Given that institutional quality is a broad concept that reflects the state of the law, individual rights and the provision of government regulation and services within a country, it is difficult to obtain precise indicators and reliable data. We use the Worldwide Governance Indicators (WGI) [23] and Country Risk Classification (CRC) of the Organization for Economic Cooperation and Development (OECD) [24] as our two broad institutional quality and governance measures. Although such indicators have attracted some criticisms, they have become widely accepted and used by policy makers and academics [11]. The WGI include not only an indicator representing political stability and absence of violence, but also indicators for control of corruption, government effectiveness, regulatory quality, rule of law, voice and accountability. The CRC measures broadly the risk of "doing business" in a country. It includes a measure of credit risk and a qualitative assessment of other factors that contribute to country level risk, such as natural disasters including floods, earthquakes and other natural hazards, as well as man-made crises such as war, expropriation, revolution, civil disturbance. We use the WGI to construct an overall indicator of institutional quality and the CRC to represent country risk.

We find that SDG welfare gains are somewhat correlated with institutional quality and highly correlated with lower country risk. Ineffective institutions and country risk seem to be especially associated with a lack of SDG progress in poorer economies. The implication is that the inability to improve governance may be constraining the long-term welfare and development of many poorer economies. On the positive side, countries with better quality institutions and lower risk appear to have made overall gains towards fulfilling the SDGs. These results suggest that effective institutions and good governance are associated with long-run development and greater sustainability. Long-term progress towards the SDGs may hinge on improved institutional quality and reduced country risk.

#### **2. Materials and Methods**

We have previously developed a methodological approach in order to assess progress towards the 17 SDGs, based on welfare economics [16,17]. Our approach to estimating the possible net benefits of making progress towards one SDG goal, while accounting for simultaneous declines or improvements in achieving other goals, is based on standard economic methods for measuring the welfare effects arising from changes in imposed quantities [25,26]. Here, we use the approach previously developed by Barbier and Burgess [16] to estimate the welfare effects of progress in attaining one SDG while accounting for interactions in achieving other SDGs. In essence, this analytical framework allows us to estimate the "willingness to pay" (WTP) in dollar terms by a representative individual for an improvement in one SDG indicator, whilst taking into account possible simultaneous changes–positive or negative–in other SDG indicators. The reason it is important to do this is that many assessments have shown that, since 2000, there has been considerable variation from country to country in the progress towards attaining the SDGs, as well as between the world and low-income economies. Furthermore, that progress in attaining any individual goal may have led to the reduction (or increase) of achievement in other goals [16,17,27–30].

We have applied our method at the world level, for the group of low-income countries and for nine representative developing countries over the period 2000–2018 [17]. We use the World Bank's classification of countries by income [31]. Low-income economies are defined by the World Bank as those with a Gross National Income (GNI) per capita of 1045 USD or less in 2020; lower middle-income economies are those with a GNI per capita between 1046 USD and 4095 USD; and upper middle-income economies are those with a GNI per capita between 4096 USD and 12,695 USD. The remaining countries of the world are classified as high income, with a GNI per capita of 12,536 USD or more. The nine representative countries we chose are Malawi, Rwanda and Uganda (three low-income economies), Bangladesh, Bolivia and the Kyrgyz Republic (three lower middle-income economies) and Colombia, Dominican Republic and Indonesia (three upper middle-income economies). In selecting these countries, we also took into account the extent to which a country has made progress since 2000 towards achieving the main goal used in our analysis, which is SDG 1 No Poverty. For each income group we chose three countries that showed long-term poverty reduction since 2000, and our nine countries vary between those with small to very large declines in poverty. Finally, in choosing countries, we also considered their geographic distribution. Consequently, we selected three countries each from Asia, Latin America and the Caribbean, and Sub-Saharan Africa [17].

Table 1 summarizes the 17 SDGs and the main indicators that we used to measure progress towards each goal. In our analysis, we chose SDG 1 No Poverty as the benchmark indicator. We estimate the change in per capita welfare from any reduction in 2000–2018 poverty rates, and adjust this to take account of any gains or losses that may occur when simultaneously achieving each of the other 16 SDGs. Further details on how we chose these indicators and the methods we use to measure these welfare gains or losses can be found in [11]. For SDG 16, Peace, Justice and Strong Institutions, we use as a representative indicator *political stability and absence of violence/terrorism* from the Worldwide Governance Indicators (WGI) [23] (Table 1).


**Table 1.** The 17 SDGs and their indicators for assessing progress.

<sup>1</sup> All indicators are available from [31], except for political stability and absence of violence/terrorism, which is from [23]. GDP = gross domestic product. GNI = gross national income. Table 1 was created by the authors and adapted from [17].

> In this article, we contrast and compare our estimates from our previous study of the net welfare changes of progress towards the 17 SDGs over 2000–2018 [17], with two institutional quality and governance measures over the same period at the world level, for the group of low-income countries and for nine representative developing countries. Here, we use the Worldwide Governance Indicators (WGI) [23] and Country Risk Classification (CRC) of the Organization for Economic Cooperation and Development (OECD) [24] for our two broad institutional quality and governance measures, respectively.

> The World Governance Indicators consists of six measures of institutional quality and governance. These include *political stability and absence of violence/terrorism*, which measures perceptions of the likelihood of political instability and/or politically-motivated violence, including terrorism. The second indicator, *control of corruption*, reflects perceptions of the extent to which public power is exercised for private gain, including both petty and grand forms of corruption, as well as "capture" of the state by elites and private interests. The third indicator, *government effectiveness*, indicates perceptions of the quality of public services, the quality of the civil service and the degree of its independence from political pressures, the quality of policy formulation and implementation, and the credibility of the government's commitment to such policies. The fourth indicator, *regulatory quality*, reflects perceptions of the ability of the government to formulate and implement sound policies and regulations that permit and promote private sector development. The fifth indicator, *rule of law*, captures perceptions of the extent to which agents have confidence in and abide by the rules of society, and in particular the quality of contract enforcement, property rights, the police, and the courts, as well as the likelihood of crime and violence. And finally the sixth indicator, *voice and accountability*, measures perceptions of the extent to which a country's citizens are able to participate in selecting their government, as well as freedom of expression, freedom of association, and a free media [23].

> These six measures of Worldwide Governance Indicators are scaled, with the lowest value at −2.5 and the highest value at 2.5. The current database covers the period from 1996 to 2019, and includes over 200 countries. Using this information, we are able to derive a measure of institutional quality based on an average of the six measures in the WGI

from 2000 to 2018 at the world level, for the group of low-income countries and for nine representative developing countries. Finally, we rescale this average institutional quality indicator over 2000 to 2018 from 0 (lowest value) to 5 (highest value).

According to the OECD, its Country Risk Classification (CRC) is "one of the most fundamental building blocks of the Arrangement rules on minimum premium rates for credit risk" [24]. Consequently, the CRC is a broad measure of country risk, which "encompasses transfer and convertibility risk (i.e., the risk a government imposes capital or exchange controls that prevent an entity from converting local currency into foreign currency and/or transferring funds to creditors located outside the country) and cases of force majeure (e.g., war, expropriation, revolution, civil disturbance, floods, earthquakes)" [24].

The CRC is scaled from 0 (lowest) to 7 (highest). The current classification covers 201 countries from 1999 to 2021. Consequently, for each country we take the average of its final year score over 2000 to 2018, and thus construct an average measure of this period at the world level, for the group of low-income countries and for nine representative developing countries.

#### **3. Results**

Table 2 summarizes the comparison of our estimates of the changes in net welfare from progress towards the 17 SDGs over the period from 2000 to 2018 with average institutional quality and average country risk over the same period at the world level, for the group of low-income countries and for nine representative developing countries.


**Table 2.** Progress towards the SDGs, institutional quality and country risk, 2000–2018.

<sup>1</sup> From [17]. <sup>2</sup> Institutional quality is the average of the 2000–2018 indicators for control of corruption, government effectiveness, political stability and absence of violence/terrorism, regulatory quality, rule of law, and voice and accountability of the Worldwide Governance Indicators [23]. Institutional quality has been rescaled from 0 (lowest quality) to 5 (highest quality). <sup>3</sup> Country risk is the average of the OECD Country Risk Classification [24]. Indicator ranges from 0 (lowest risk) to 7 (highest risk). Table 2 was created by the authors.

> Our analysis of changes in net welfare from progress towards the 17 sustainable development goals shows that there are substantial differences in the level of interactions among the SDGs and the corresponding net welfare effects at the global level compared to that experienced by low-income countries [17]. At the global level, there are some welfare losses through tradeoffs with declining SDG indictors over 2000–2018, but these losses are mostly compensated by increases in other SDG indictors. Once such interactions are taken into account, there is an overall net gain in welfare of 3633 USD per person on average at the world level from 2000 to 2018 (Table 2). Therefore, our welfare analysis suggests that there has been an overall enhancement in sustainability at the global level from 2000 to 2018.

> In comparison, for poor economies, the tradeoffs from declining SDG indicators surpass the gains in welfare from improving indicators over the period from 2000 to 2018. As a result, for low-income countries, these interactions imply that countries in this group have experience a net loss in welfare over the period from 2000 to 2018 of 29 USD per person on average. This means that in contrast to the world as a whole, low-income economies

experienced an overall reduction rather than an improvement in sustainability from 2000 to 2018.

This difference in the sustainability performance of poorer economies is also demonstrated across our nine representative countries. Here, we see that all nine countries benefit from progress towards SDG 1 No Poverty. However, when we take into account interactions with other SDGs, the less well-off countries tend to perform less well. For example, two of the three low-income economies–Rwanda and Uganda–and two of the three lower middle-income economies–Bolivia and the Kyrgyz Republic–all experience an overall loss in sustainability over the period from 2000 to 2018. In contrast, over this same period, the three upper middle-income economies demonstrate substantial gains from overall increase in sustainability over the period from 2000 to 2018 (Table 2).

As Table 2 shows, a similar pattern emerges for average institutional quality over 2000– 2018, which ranges from 0 (low quality) to 5 (high quality). The world displays a much higher level of effective institutions and governance (2.5) than low-income countries (1.4). However, institutional quality is more mixed among our nine representative countries. For example, Colombia, Dominican Republic and Indonesia (our three upper middle-income economies) generally have the highest institutional quality, as well as Bolivia (which is a lower middle-income economy), and also Malawi and Rwanda (which are low-income countries).

Country risk appears to be much more closely associated with net welfare gains and losses (Table 2). This indicator measure ranges from 0 (low risk) to 7 (high risk). Once again, low-income countries display much higher risk (6.9) compared to the world on average (4.5). This is also the case at the country level. For example, Malawi, Rwanda and Uganda (our three low-income countries) show country risk levels of 7.0, 6.8 and 6.4 respectively. Very high country risk (7.0) is also displayed by the Kyrgyz Republic, which is a lower middle-income economy, and Bangladesh and Bolivia (also middle-income economies), have slightly lower risk at 5.7 and 6.3 respectively. In contrast, the country risk for the three countries in the upper middle-income category are close to the world average.

#### **4. Discussion**

Figures 1 and 2 further aid the interpretation of these results, especially with respect to understanding whether institutional quality and governance help or hinder progress towards the 17 Sustainable Development Goals (SDGs) of UN Agenda 2030.

Figure 1 depicts the pairwise comparison between net welfare gains or losses from attaining the SDGs over 2000–2018 with average institutional quality over this period for the world level, for the group of low-income countries and for nine representative developing countries. Across these estimates, institutional quality displays modest correlation (0.49) with net welfare change in progress towards sustainability over 2000–2018.

As Figure 1 shows, the association between more effective institutions, good governance and progress towards the SDGs over 2000–2018 cannot be ruled out. On the whole, countries with better institutional quality achieved more progress compared to those with weaker institutions. Especially notable is that Colombia, Dominican Republic and Indonesia (the three upper middle-income countries), appear to show reasonable institutional quality for developing countries and achieved significant net welfare gains through SDG progress over 2000–2018.

Overall, by comparing and contrasting our welfare analysis [17] to average institutional quality over 2000–2018 we are able to provide some evidence to support the view that institutional effectiveness and good governance are essential for successful long-run sustainable development [1–13,22]. As our results show for our three upper middle-income countries, there appears to be a synergistic relationship between economic progress, sustainability and enhancements in institutional quality. Unfortunately, several countries appear to be experiencing a trade-off between institutional quality and making progress towards the 17 SDGs. In particular, for poorer countries, the lack of progress towards sustainability and strengthening governance may create a chronic problem that undermines progress on long-term development and improvements in welfare.

**Figure 1.** This figure plots the pairwise estimates from Table 2 of net welfare change per capita in achieving the 17 SDGs over 2000–2018 and the average institutional quality over 2000–2018 for the world level, for the group of low-income countries and for nine representative developing countries. These estimates have a positive correlation of 0.49.

− − **Figure 2.** This figure plots the pairwise estimates from Table 2 of net welfare change per capita in achieving the 17 SDGs over 2000–2018 and the average country risk over 2000–2018 for the world level, for the group of low-income countries and for nine representative developing countries. These estimates have a negative correlation of −0.72.

> Figure 2 displays the pairwise comparison between net welfare gains or losses from attaining the SDGs over 2000–2018 with average country risk over this period for the

world level, for the group of low-income countries and for nine representative developing countries. Across these estimates, country risk displays high negative correlation (−0.72) with net welfare change in achieving the SDGs over 2000–2018.

Figure 2 shows that the association between lower country risk and improvements towards the SDGs over the period from 2000 to 2018 is very strong. Countries with lower risk achieved more progress compared to those with higher risk. Especially striking is the results for Colombia, Dominican Republic and Indonesia (our three upper middle-income countries), which generally have much lower risk and higher net welfare gains compared to less well-off countries and the group of low-income economies. The group of low-income economies tend to have much higher country risk and display only modest gains–and often net losses–in attaining the SDGs over 2000–2018.

The strong association between country risk and sustainability performance may seem surprising, but it fits with other analyses of the relationship between business climate and long-run economic performance and attaining development goals, such as poverty reduction [13,17,22]. It also accords with other analyses that show, as a whole, poorer economies have not been faring well in overall progress towards the SDGs, and especially have performed badly in terms of the environmental goals SDGs 11–15 [16,17,27,28,30]. As explained by Jeffrey Sachs and colleagues, ineffective institutions may be a factor: poorer economies not only have lower overall SDG Index scores but also "they tend to lack adequate infrastructure and mechanisms to manage key environmental challenges covered under SDGs 12–15" [30], p. 25.

These results provide further support to the substantial empirical literature in economics that has established a persuasive link between institutions and long-run economic development [1–13,22]. These results also confirm recent studies that have shown that more effective institutions and governance are essential to reducing extreme poverty and achieving other development goals that are important to low and middle-income economies [12,13].

#### **5. Conclusions**

This article compares and contrasts estimates of the changes in net welfare from progress towards the 17 SDGs over the period from 2000 to 2018 with measures of institutional quality and country risk over the same period for the world level, for the group of low-income countries and for nine representative developing countries. These comparisons shed some light on whether institutional quality and governance help or hinder progress towards the 17 Sustainable Development Goals (SDGs) of UN Agenda 2030.

Although it is difficult to obtain precise indicators and reliable data on the broad concept of institutional quality and governance, and such indicators have attracted notable criticisms in the past, the WGI and CRC measures of institutional quality and governance are now widely accepted by policy makers and academics [11]. Overall, we find that SDG welfare gains are somewhat correlated with institutional quality and highly correlated with lower country risk. Countries with better quality institutions and lower risk appear to have made overall gains towards fulfilling the SDGs. These results suggest that good governance and institutional effectiveness are associated with success in achieving long-run sustainable development objectives. Therefore, long-term progress towards the SDGs may hinge on improved institutional quality and reduced country risk.

Unfortunately, ineffective institutions and country risk seems especially associated with lack of SDG progress in poorer economies. The implication is that, for many lowincome countries, the lack of progress towards sustainability and improving governance may be a fundamental problem that is undermining their long-term development and welfare. This does not bode well for poorer economies, who generally display poorer institutional quality and much higher country risk. In addition, these economies have struggled to achieve progress towards attaining the 17 Sustainable Development Goals, and especially SDGs 11–15 [16,17,27,28,30].

A major concern is that poorer economies are facing even greater development burdens with the ongoing COVID-19 pandemic. They are particularly affected by mounting debt, inequality and poverty. These challenges will further constrain their ability to build strong institutions, improve governance and reduce credit risk.

Due to the pandemic, global debt reached 289 USD by the end of the first quarter of 2021, and accounts for just over 369% of global GDP [32]. Around 86 trillion USD of this debt is in emerging market economies [33]. Research has shown that mounting debt can severely exacerbate the duration and intensity of recessions in emerging market economies, in part due to less supportive fiscal policies in these countries during times of crises [34]. Emergency measures established during the COVID-19 pandemic, including the Debt Service Suspension Initiative that was established by the International Monetary Fund and the World Bank, has provided poorer countries a short-term respite from payments on debt. However, there is not yet any sign of a longer-term comprehensive debt relief program for the world's poorest countries [35]. Growing indebtedness in developing countries will further undermine their credit worthiness and make it extremely difficult to ameliorate their high levels of country risk.

Furthermore, inequality has increased during the pandemic as the world's richest have become wealthier and poverty reduction has been setback substantially [26–28]. Worldwide in 2020, there was an increase of 3.9 trillion USD in the wealth of billionaires. In contrast, the total number of people living in poverty may have increased by 200 to 500 million during the pandemic [36]. As many as 70 to 100 million people across the world could fall into extreme poverty, which is the first rise in extreme poverty over two decades [37,38]. Shared prosperity–the relative increase in the incomes of the bottom 40% of the population compared to that of the entire population–is anticipated to decrease sharply in nearly all countries in 2020–2021. This decline in shared prosperity will be even more significant if the pandemic's economic impacts continue to fall disproportionately on poor people [38].

The pandemic could be especially devastating for the inclusivity of global development seriously in terms of extreme poverty and shared prosperity. Even before the COVID-19 pandemic, the global community was still a long way from achieving critical sustainability and development objectives for the most vulnerable people and countries. For example, in 2019, as many as 736 million people lived in extreme poverty, 821 million were undernourished, 785 million people lacked basic drinking water services, and 673 million people across the globe were without sanitation [39]. About 3 billion people did not have access to clean cooking fuels and technology, and on top of this, of the 840 million people without electricity, 87% lived in rural areas. It has been projected that as many as 28 poor countries could fall short of attaining SDGs 1–4, 6 and 7 by 2030 [18].

As a final observation, our article provides support for the view that long-term progress towards the SDGs may be associated with improved institutional quality and reduced country risk. However, this association does not necessarily imply that "the causality runs from institutions to economic development, ignoring the important possibility that economic development changes institutions" [2], p. 476. Clearly, further research and more country-level data are required to statistically analyze the relationship between net welfare changes, institutional qualities and country risks to determine conclusively whether improved institutions and governance will necessarily lead to better progress towards sustainability, as reflected in the 17 Sustainable Development Goals. As our article suggests, this is a rich and important area for further research.

**Author Contributions:** Conceptualization, E.B.B. and J.C.B.; methodology, E.B.B.; formal analysis, E.B.B.; writing—original draft preparation, E.B.B. and J.C.B.; writing—review and editing, E.B.B. and J.C.B. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.

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