Search

The concept of the Metaverse, originating from Neal Stephenson’s 1992 novel Snow Crash, has transitioned from a speculative fiction idea into a complex cultural and technological reality. This paper explores the evolution of the Metaverse as both a digital twin of the physical world and a new ‘cultural logic’ permeating various sectors such as gaming, education, and commerce. By integrating immersive technologies such as virtual reality, the Metaverse offers a blended “phygital” environment where users engage in activities ranging from social interactions to commercial transactions, seamlessly merging physical and digital realities. This study delves into how foremost technology leaders have influenced the Metaverse’s trajectory, focusing on transforming it from a gaming interface to a broad digital ecosystem. We analyze the role of blockchain technology in facilitating a network of interconnected spaces that allow for the preservation of digital identities and assets across platforms, highlighting the challenges and potential of achieving interoperability. Ultimately, this paper presents the Metaverse as a paradigm shift in digital interaction, suggesting future directions where digital and physical realities might further converge. Through a comprehensive review of technological advancements and cultural shifts, we discuss the implications of this convergence for future digital interaction frameworks and societal norms.

In this paper, we develop a visualization process for partial orders derived from considering many numerical indicators on a statistical population. The issue is relevant, particularly in the field of socio-economic evaluation, where explicitly taking into account incomparabilities among individuals proves much more informative than adhering to classical aggregative and compensative approaches, which collapse complexity into unidimensional rankings. We propose a process of visual analysis based on a combination of tools and concepts from partial order theory, multivariate statistics and visual design. We develop the process through a real example, based on data pertaining to regional competitiveness in Europe.

As of the past century, the analysis and the graphical representation of inequality play a very important role in economics. In the literature, several curves have been proposed and developed to simplify the description of inequality. The aim of this paper is a review and a comparison of the most known inequality curves, evaluating the features of each, with a particular focus on interpretation.

Los elementos traza, que incluyen a los metales pesados, llegan a los ecosistemas acuáticos desde fuentes naturales y antrópicas. Los metales pesados se encuentran entre los contaminantes ambientales más importantes debido a su toxicidad, permanencia y tendencia a acumularse en los organismos acuáticos, por lo que su estudio es necesario por el riesgo ambiental que representan. El objetivo de este trabajo es presentar los resultados más relevantes en relación a los niveles de metales pesados existentes en diferentes compartimentos de lagos del noroeste de Patagonia. Los estudios realizados determinaron concentraciones de elementos traza en testigos sedimentarios, sedimentos suspendidos, agua, plancton, macroinvertebrados y músculo e hígado de peces. En términos generales, los niveles de metales pesados en los distintos compartimentos fueron similares a los valores medidos en otros ambientes de agua dulce. La excepción la constituyen el mercurio y la plata, que presentan enriquecimientos superiores a los niveles de línea de base de la zona en las últimas décadas. En el caso de la plata fueron observadas mayores concentraciones en sitios cercanos a los asentamientos humanos, y en algunos casos alcanzaron valores correspondientes a situaciones de contaminación moderada. En ningún caso, la acumulación de metales en músculo de peces superó los límites considerados para el consumo humano. Esta revisión permite identificar niveles de referencia y evaluar la tendencia del impacto antrópico, aportando información de base para futuros monitoreos de los ambientes lacustres de la región.

Abstract Interspecific differences in arsenic bioaccumulation and organ distribution (muscle, liver, kidney and gills) in three predator fish (creole perch, rainbow trout and brown trout) from a Patagonian lake impacted by volcanic eruptions were studied. Arsenic in fish organs were compared analyzing: 1) temporal (before and after volcanic eruption) and spatial (near and far from the volcano) influence of Puyehue-Cordón Caulle volcanic complex activity on arsenic concentrations; 2) the influence of growth (as total length), organ type and their interactions over arsenic accumulation; and 3) arsenic speciation and total arsenic relationship with carbon to nitrogen ratios (C:N), as a proxy of lipid presence, in fish muscle. In general, total arsenic concentrations in creole perch organs were 2–7 times higher than those recorded in the corresponding organs of salmonids. Arsenic was preferentially accumulated in liver and kidney in the three fish species. The influence of the volcanic activity over arsenic concentrations was more evident in creole perch: organs from creole perch captured closest to the volcano exhibited higher arsenic concentrations. Temporal variations were not so consistent. No clear relationship between arsenic and fish length was observed. Positive and linear relationship between arsenic in all pair of organs was found in creole perch, while rainbow trout showed a quadratic relationship between muscle and the remaining organs, indicating different arsenic assimilation-elimination relationships between organs and fish. The arsenic liver:muscle ratio in the three fish species was greater than 1, suggesting some level of arsenic stress. Arsenobetaine (AB) and dimethylarsinic acid (DMA) were the dominant arsenic species in muscle of these fish, having creole perch 3–4 times higher AB than rainbow trout. A positive relationship between C:N ratio and total arsenic concentrations was found, with higher C:N in creole perchs near the volcano. In terms of food safety, no inorganic arsenic compound were detected, therefore arsenic levels in fish from Lake Nahuel Huapi does not represent any health risk to consumers. Graphical abstract fx1 Highlights • Arsenic concentration in four tissues from three predator fish were compared. • Concentrations were higher in benthivorous fish tissues and near the volcanic source. • Arsenic concentrations were higher in liver and kidney. • Only arsenobetaine and dimethylarsinic acid were detected in fish muscle. • C:N ratios of fish were positively related to arsenic concentrations. [ABSTRACT FROM AUTHOR]

At the beginning of the 21st century, digital imaging technology replaced the traditional silver-halide film photography which had implications in Ag contamination. Lake Nahuel Huapi is a popular Patagonia tourist destination impacted by municipal silver (Ag) contamination from photographic processing facilities since 1990's. Silver concentrations in a dated sediment core from the lake bottom showed a 10-fold increase above background levels in the second half of the 20th century, then a decrease. This trend corresponds well with published annual global photography industry demand for Ag, which clearly shows the evolution and replacement of the traditional silver-halide film photography by digital imaging technology. There were significant decreases in Ag concentrations in sediments, mussels and fish across the lake between 1998 and 2011. Lower trophic organisms had variable whole-body Ag concentrations, from 0.2–2.6 μg g −1 dry weight (DW) in plankton to 0.02–3.1 μg g −1 DW in benthic macroinvertebrates. Hepatic Ag concentrations in crayfish, mussels and predatory fish were significantly elevated relative to muscle which often have Ag concentrations below the detection limit (0.01–0.05 μg g −1 DW). Trophodynamic analyses using δ 15 N and whole-body invertebrate and muscle Ag concentrations indicated food web biodilution trends. High sedimentation rates in conjunction with the reduction of silver waste products discharged to the lake, as a result of the change to digital image processing technologies, are resulting in unplanned but welcome remediation of the Ag contamination in Lake Nahuel Huapi. [ABSTRACT FROM AUTHOR]

The food web structure of the largest lake in northwest Patagonia, Lake Nahuel Huapi (area 557 km 2 ), was investigated. Fish, benthic macroinvertebrates, plankton and primary producers were analyzed for stable nitrogen (δ 15 N) and carbon (δ 13 C) isotopes in three sites with contrasting morphometry and environmental characteristics. δ 15 N and δ 13 C revealed a similar food web structure between basins but with distinct isotopic baselines. The SIAR (Stable Isotope Analysis in R) mixing model was used to study potential food sources (benthic or pelagic) for adult fish. Results indicated that energy flow to fish from both habitats is different for each site and species, and does not depend on the basin morphometry. An ontogenetic shift in the carbon source and trophic level was observed in some of the fish species, revealing a coupling between the pelagic and bentho-littoral habitats of the lake. Our findings complement the existing literature on trophic interactions between introduced and native fish, and provide novel information on plankton composition, food web structure and energy flow in a large lake of North Patagonia that can be extrapolated to other understudied lakes in the area. [ABSTRACT FROM AUTHOR]

Abstract: Fish, benthic macroinvertebrates, macrophytes, biofilm, plankton, and terrestrial material were analyzed for stable nitrogen (δ15N) and carbon isotopes (δ13C) to study the food web structure of a double-basined, ultra-oligotrophic lake in northwest Patagonia. The δ15N values of all biota were consistently higher in Moreno East basin, probably caused by a higher anthropogenic impact; however, the estimated trophic positions of fish showed no differences between basins, indicating that fish are feeding from food chains with different δ15N baselines. Fish δ13C values were higher in Moreno West basin but no pattern was observed for the rest of the organisms analyzed. The different hydrogeomorphic characteristics between the basins could lead to these differences in the C signatures of fish. SIAR (Stable Isotope Analysis in R) mixing model was used to study possible food sources for adult fish and the results were contrasted with published gut content analysis. According to the model, in both basins small size fish such as Small Puyen (Galaxias maculatus) and juvenile fish, had the highest relative isotopic contribution to introduced Rainbow Trout (Oncorhynchus mykiss) and Brook Trout (Salvelinus fontinalis), which had lower contributions from other sources such as insect larvae, decapods, and snails. On the contrary, decapods and insect larvae were isotopically more important for the native Creole Perch (Percichthys trucha) than small fish in both basins. An ontogenetic shift in the carbon source and trophic level was observed in Puyen Chico and Rainbow Trout from the West basin. [Copyright &y& Elsevier]

Background: T-type calcium channels have been shown to play an important role in the initiation and maintenance of neuropathic pain and represent a promising therapeutic target for new analgesic treatments. Ethosuximide (ETX), an anticonvulsant and a T-type channel blocker has shown analgesic effect in several chronic pain models but has not yet been evaluated in patients with neuropathic pain., Methods: This proof-of-concept, multicentre, double-blind, controlled and randomized trial compared the efficacy and safety of ETX (given as add-on therapy) to an inactive control (IC) in 114 patients with non-diabetic peripheral neuropathic pain. After a 7-day run-in period, eligible patients aged over 18 years were randomly assigned (1:1) to ETX or IC for 6 weeks. The primary outcome was the difference between groups in the pain intensity (% of change from the baseline to end of treatment) assessed in the intention-to-treat population. This study is registered with EudraCT (2013-004801-26) and ClinicalTrials.gov (NCT02100046)., Results: The study was stopped during the interim analysis due to the high number of adverse events in the active treatment group. ETX failed to reduce total pain and showed a poor tolerance in comparison to IC. In the per-protocol analysis, ETX significantly reduced pain intensity by 15.6% (95% CI -25.8; -5.4) from baseline compared to IC (-7.8%, 95% CI -14.3; -1.3; p = 0.033), but this result must be interpreted with caution because of a small subgroup of patients., Conclusion: Ethosuximide did not reduce the severity of neuropathic pain and induces, at the doses used, many adverse events., Significance: This article shows that ETX is not effective to treat neuropathic pain. Nevertheless, per-protocol analysis suggests a possible analgesic effect of ETX. Thus, our work adds significant knowledge to preclinical and clinical data on the benefits of T-type calcium channel inhibition for the treatment of neuropathic pain., (© 2018 European Pain Federation - EFIC®.)