Global use of materials has significantly increased over recent decades, causing a wide range of environmental and social concerns. In this study, we use the latest available data from the UN database on global material flows to investigate the Environmental Kuznets Curve (EKC) hypothesis for two widely used material flow indicators, Domestic Material Consumption and Material Footprint, for a dataset of 147 countries. Using both semiparametric and parametric methods over a longer period than any previous study (1970-2019), we find no evidence in support of the EKC hypothesis. A concerning result is that material-income elasticities are higher after 1989, implying that the situation has not improved. We conclude that major changes have not yet occurred in the income-material use relationship and that strong policy measures remain necessary to reduce material consumption.
This study evaluated the performance of two portable spectral devices (visible: Vis; near-infrared: NIR) and one benchtop combined Vis/NIR instrument for predicting beef biochemical traits related to meat quality. A total of 497 muscle samples were collected from 55 fattening farms across five European countries. Reference values were obtained exclusively from pooled samples. For the benchtop device, two sampling strategies were compared: 1) direct scanning of pooled samples (n = 99) used for reference analyses, and 2) scanning individual samples followed by spectral averaging to match pooled references. Partial least squares regression models were developed using several preprocessing methods. For total and heme iron, predictive performance was also evaluated by separately analyzing the visible region of the benchtop device. Results showed that the benchtop Vis/NIR instrument clearly outperformed the portable devices, providing higher prediction accuracies for all traits across the full spectral range. Compared with portable instruments, the benchtop device achieved superior performance for proximate composition (R-2 = 0.51-0.85 vs 0.10-0.22), major fatty acids (R-2 = 0.50-0.68 vs 0.01-0.31), and total and heme iron (R-2 = 0.79-0.93 vs 0.46-0.91). Moreover, scanning individual samples and averaging spectra yielded better prediction models than direct scanning of pooled samples, with good accuracies for moisture, protein, fat content, major saturated and monounsaturated fatty acids, and iron. Conversely, poor prediction (R-2 < 0.40) was observed for polyunsaturated fatty acids, TBARS, carnosine, anserine, zinc, selenium and B-group vitamins. Overall, Vis/NIR spectroscopy showed strong potential for beef quality assessment, although further optimization is required for portable devices.
The energy transition triggers urgent questions about what values are important, who controls transitional processes, and who has the power to define the answers to the climate crisis. Energy companies claim their central role in the development of renewable energy as the ultimate solution. However, communities affected by large-scale renewable energy projects have extensively raised environmental and social justice concerns and denounced the industry's poor practices and abuses.In this article, we analyse 15 socio-environmental conflicts around renewable energy projects owned by the Enel Group, one of the world's largest energy utilities, through the values and valuation languages of the affected communities. We map them onto five dimensions: environmental, health-related, socio-economic, ontological, and political. We build on environmental justice and ecological economics literature on valuation languages and employ counter-accounting to gather bottom-up evidence of grievances.We argue that, while the company claims that RE is the ultimate solution and the ‘Creating Shared Value’ approach is beneficial to all parties, those impacted by Enel's projects question the corporate model of energy transition and defend a plurality of values embedded in relational worldviews that are systematically misrecognised. We eventually criticise the corporate self-attributed moral and value-centred mandate in the energy transition and call for inclusive research about desirable energy futures rooted in plural and relational value systems.
India generates rapidly growing volumes of electronic waste but struggles to regulate these flows. This article traces the contested control of India’s printed circuit board (PCB) destruction network, examining who controls materials, labor, capital, and profits at each stage — from doorstep collection to international end-refining. Drawing on 25 expert interviews (2022–2023) and site visits in Delhi, we combine industrial ecology’s attention to material flows with political ecology’s focus on power and labor relations. We find that India’s PCB destruction network is not a failing system but a functioning one, even if its logic is not captured by the regulatory framework designed to govern it. Collection is controlled by informal networks whose infrastructure outperforms formal alternatives. Dismantling concentrates through skilled manual labor in dense informal communities that regulation has rendered invisible. End-refining is contested between European smelters, Chinese buyers, and India’s ambitions for domestic critical raw material recovery. Three lenses structure the analysis: the interdependence of formal and informal economies, where selective formalization serves the state, formal recyclers, and international smelters while the workers whose labor constitutes the network remain unrecognized; the power relations of labor and capital, in which control over the upstream stages rests on skilled labor organized through petty capital while global capital controls the profitable downstream stage; and geopolitical competition, in which India seeks sovereignty over materials it can neither process domestically nor prevent from leaving informally. We show how the valorization of secondary raw materials is shaped by informal networks, capital relations, and geopolitical interests.
We study the n.-dimensional Lotka-Volterra systems (x) over dot = x(t) (Sigma(n)(j=1) a(tj) x(j) + b(t)), i = 1,..., n, in R-n, where a(tj), b(t) is an element of R. A necessary and sufficient condition is obtained for the existence of a Darboux invariant of the form e(-st) Pi(t=1) x(t)(lt) with s not equal 0 for such systems. Based on this condition, the Lotka-Volterra systems are divided into three classes. For each class, we establish results on the existence of equilibrium points, bounded orbits, periodic orbits, and first integrals.
