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Non-biodegradable plastics have been extensively used for food packaging due to their outstanding properties that preserve food quality during transportation and shelf-life. The global awareness of plastic pollution has led to the development of environmentally friendly technologies for food packaging such as biodegradable polymers, edible films and coatings, and active or smart packaging. However, the petroleum-based polymers market seems not to be interested in setting back and current waste management strategies continue to be deficient in both technical and economic aspects. This work aimed to provide insights into the state-of-the-art technologies for food packaging based on the advances that have been made to improve the moisture, heat, and barrier properties of novel materials that could close the gap to conventional plastics in terms of performance and costs. This literature review takes a multidisciplinary approach, focusing on the required properties of food packaging and the potential impact on the physicochemical properties of food products. The aim is to identify gaps between current technologies and market demand that impede the alignment of the food packaging industry with global environmental policies. Several sustainable packaging options were identified, such as biopolymers like PLA or PBAT. However, most successful packaging solutions are made up of PVA, chitosan, gelatin, or films based on proteins. In both cases, the addition of essential oils, natural extracts, or nanoparticles to the packaging material has demonstrated its effectiveness in improving performance and ensuring food preservation over an extended period on the shelf. However, a significant research gap has been identified regarding the scaling up of packaging materials based on natural polymers, despite the technology appearing to be sufficiently advanced for practical implementation. Hence, it is necessary not only to optimize parameters to enhance functionality and mechanical properties but to demonstrate their feasibility for industrial production. Furthermore, it is essential to assess their environmental impact. It is important to provide evidence of the feasibility of real-world applications of the new materials developed, demonstrating their effectiveness under critical storage conditions for the preservation of different food groups.

The management of municipal solid waste (MSW) is a complex and expensive task. This is especially the case in developing countries, where waste generation rates are continuously increasing and where current MSW management strategies are focused on inadequate practices, such as landfilling and incineration, which result in numerous health and environmental problems. The anaerobic digestion (AD) of MSW has been implemented worldwide as a solution to decrease the amount of waste ending up in landfills. This process allows for the recovery of energy from the organic fraction of MSW (OFMSW) in the form of biogas, which is largely composed of methane. Therefore, the goal of the present study was to evaluate the biochemical methane potential (BMP) of the OFMSW generated within different socioeconomic strata of the Metropolitan Area of Guadalajara (MAG), Mexico. From a microscale perspective, the microbial communities within the experimental AD system were analyzed using high-throughput sequencing of the 16S rRNA gene to assess the relationship between these communities and the biogas composition. This microbial identification revealed a typical AD composition consisting of the following six phyla: Actinobacteria, Bacteroidetes, Chloroflexi, Euryarchaeota, Firmicutes, and Proteobacteria. Furthermore, through the identification of Methanobacterium and Methanosaeta , two methanogenesis pathways (hydrogenotrophic and acetoclastic) were pinpointed. From a macroscale perspective, a multi-stage Gompertz kinetic model was used to describe cumulative biogas production. This model considered the complex nature of the OFMSW substrate in order to estimate the potential level of biogas production in the MAG using a weighted average that was based on the size of the population in each socioeconomic stratum evaluated (732.8 mL⋅g −1 VS). This novel contribution to the literature provides an estimation of the potential economic, energetic, and environmental benefits of treating the OFMSW produced in the MAG through AD. Through this approach, an estimated 8.5 MWh·year −1 of electrical power could be produced, translating into 1.13 million USD of yearly revenue and resulting in reduced GHG emissions (10,519 tonne CO 2eq ⋅year −1 ).

Nowadays, poly(lactic acid) (PLA) is one of the most used biobased polymers with significant growth in the global market. Even though one of the main characteristics of PLA is its biodegradability, this process can generate environmental impact, soil use, and genotoxicity of residues. Additionally, PLA still has a considerably high cost, limiting its competitiveness with conventional oil-based thermoplastics. In this sense, this review discusses the reprocessing and recycling of PLA as an alternative to direct biodegradation to explore more economically viable end-of-life options (EoL). The PLA recycling methods are described, and mechanical recycling is highlighted due to its low environmental impact and common availability. The use of specific additives and their importance in maintaining acceptable PLA properties after reprocessing cycles are presented. The reprocessing and recycling effects on the molecular structure, rheological properties, and thermo-mechanical properties of PLA are shown and discussed. Weathering and abiotic factors are also included since they influence PLA recycling by generating previous degradation. In addition, the environmental impact of PLA recycling methods is presented and compared to other EoL options based on life cycle assessment (LCA).

Narrative medicine has great educational potential in the degree of medicine. This study explores for the first time the use of narrative medicine in relation to longitudinal evolution of medical vocation for the same group of students. In the context of the Degree in Medicine at the Universidad Autónoma de Madrid (Spain), students wrote narratives about what it meant to them to be a doctor at the beginning and end of their studies. The narratives of 338 students of the academic years 2012/13–2017/18 and 2013/14–2018/19 were analysed and compared. Students mostly pursued a degree in medicine on account of humanistic motivations, which are reinforced throughout their degree. In contrast, up to 10% of students reference to have experienced vocational crises and suffered frustration, with up to 25% of the references pertaining to having made significant sacrifices. Students maintain and evolve their humanistic, patient-centred vision throughout their degree studies, despite the difficulties they appear to encounter. We suggest that efforts must be made to include more humanistic perspectives in the medical degree to keep this trend, which may improve both the educational experience created in universities and the health care given to patients.

•Work based on PET simulations to evaluate the impact of quantification in epilepsy.•Eight nuclear medicine physicians reviewed 125 simulated [¹⁸F]FDG-PET images.•Quantification improved the foci identification and enhanced diagnostic confidence.•Simulation offers a valuable tool to assess and validate quantification methods.•Their use can support better surgical planning in drug-resistant epilepsy patients. Quantitative analysis of [18F]FDG-PET images is expected to improve the localization of foci in non-lesional epilepsy. However, the lack of reliable gold standards has prevented a comprehensive evaluation of the potential improvements derived from this approach. Here, we aimed at evaluating these improvements using a novel dataset of realistic simulated studies. 125 realistic simulated [18F]FDG-PET studies were generated (100 with synthetic hypometabolic foci (HF) with different levels of identification complexity and 25 controls). Eight nuclear physicians performed visual rating (VR) and were given the chance to modify their assessment after reviewing quantitative results (QR). Physicians reported the presence/absence of HF, HF location, and diagnostic confidence (DC) before/after QR. Success Rate (SR) of physician’s assessments was analyzed, as well as inter-rater agreement and changes in DC. In 31.3% of the assessments, physicians changed their interpretation after QR, with SR increasing from 16.3% to 61.0% in these cases. Overall SR improved from 49.5% in VR to 63.5% in QR, mostly on pathologic cases (relative improvement: +34.0%). Improvement was found at each level of HF identification complexity and was higher for challenging cases (relative improvement: +71.8%). Inter-rater agreement also improved significantly (0.273 vs. 0.475, p < 0.001). QR also significantly increased DC (\"High\" confidence of 8.1% on VR vs. 38.5% on QR, p < 0.001). Quantitative analysis significantly improved diagnostic accuracy, confidence and inter-rater agreement, especially in challenging cases. Furthermore, this work introduces a novel methodological approach using simulated MRI-negative epilepsy [18F]FDG-PET images for realistic quantification research studies. [Display omitted]

The differential vulnerability of dopaminergic neurons of the substantia nigra pars compacta (SNc) is a critical and unresolved question in Parkinson´s disease. Studies in mice show diverse susceptibility of subpopulations of nigral dopaminergic neurons to various toxic agents. In the primate midbrain, the molecular phenotypes of dopaminergic neurons and their differential vulnerability are poorly characterized. We performed a detailed histological study to determine the anatomical distribution of different molecular phenotypes within identified midbrain neurons and their selective vulnerability in control and MPTP-treated monkeys. In the ventral tier of the SNc ( nigrosome ), neurons rich in Aldh1a1 and Girk2 are intermingled, whereas calbindin is the marker that best identifies the most resilient neurons located in the dorsal tier and ventral tegmental area, recapitulating the well-defined dorsoventral axis of susceptibility to degeneration of dopaminergic neurons. In particular, a loss of Aldh1a1+ neurons in the ventral SNc was observed in parallel to the progressive development of parkinsonism. Aldh1a1+ neurons were the main population of vulnerable dopaminergic nigrostriatal-projecting neurons, while Aldh1a1- neurons giving rise to nigropallidal projections remained relatively preserved. Moreover, bundles of entwined Aldh1a1+ dendrites with long trajectories extending towards the substantia nigra pars reticulata emerged from clusters of Aldh1a1+ neurons and colocalized with dense cannabinoid receptor 1 afferent fibers likely representing part of the striatonigral projection that is affected in human disorders, including Parkinson´s disease. In conclusion, vulnerable nigrostriatal-projecting neurons can be identified by using Aldh1a1 and Girk2. Further studies are needed to define the afferent/efferent projection patterns of these most vulnerable neurons.

Dopaminergic neurons in the ventral tier of the substantia nigra pars compacta (SNc) degenerate prominently in Parkinson’s disease (PD), while those in the dorsal tier and ventral tegmental area are relatively spared. The factors determining why these neurons are more vulnerable than others are still unrevealed. Neuroinflammation and immune cell infiltration have been demonstrated to be a key feature of neurodegeneration in PD. However, the link between selective dopaminergic neuron vulnerability, glial and immune cell response, and vascularization and their interactions has not been deciphered. We aimed to investigate the contribution of glial cell activation and immune cell infiltration in the selective vulnerability of ventral dopaminergic neurons within the midbrain in a non-human primate model of PD. Structural characteristics of the vasculature within specific regions of the midbrain were also evaluated. Parkinsonian monkeys exhibited significant microglial and astroglial activation in the whole midbrain, but no major sub-regional differences were observed. Remarkably, the ventral substantia nigra was found to be typically more vascularized compared to other regions. This feature might play some role in making this region more susceptible to immune cell infiltration under pathological conditions, as greater infiltration of both T- and B- lymphocytes was observed in parkinsonian monkeys. Higher vascular density within the ventral region of the SNc may be a relevant factor for differential vulnerability of dopaminergic neurons in the midbrain. The increased infiltration of T- and B- cells in this region, alongside other molecules or toxins, may also contribute to the susceptibility of dopaminergic neurons in PD.

The self-organising global dynamics underlying brain states emerge from complex recursive nonlinear interactions between interconnected brain regions. Until now, most efforts of capturing the causal mechanistic generating principles have supposed underlying stationarity, being unable to describe the non-stationarity of brain dynamics, i.e. time-dependent changes. Here, we present a novel framework able to characterise brain states with high specificity, precisely by modelling the time-dependent dynamics. Through describing a topological structure associated to the brain state at each moment in time (its attractor or ‘information structure’), we are able to classify different brain states by using the statistics across time of these structures hitherto hidden in the neuroimaging dynamics. Proving the strong potential of this framework, we were able to classify resting-state BOLD fMRI signals from two classes of post-comatose patients (minimally conscious state and unresponsive wakefulness syndrome) compared with healthy controls with very high precision.

The construction industry generates a considerable amount of waste. Faced with this undesirable situation, the ready-mix concrete sector, in particular, has invested energy and resources into reusing its own waste in its production process as it works towards the goal of more sustainable construction. This study examines the feasibility of incorporating two types of concrete waste, which currently end up in landfill, into the production process of ready-mix concrete: the waste generated during the initial production stage (ready-mix concrete waste), and waste created when demolition waste is treated to obtain artificial aggregate. The first phase of the study’s methodology corroborates the suitability of the recycled aggregate through characterization tests. After this phase, the impact of incorporating different percentages of recycled coarse aggregate is evaluated by examining the performance of the produced concrete. The replacement rate varied between 15% and 50%. The results indicate that recycled aggregates are, indeed, suitable to be incorporated into ready-mix concrete production. The impact on the final product’s performance is different for the two cases examined herein. Incorporating aggregates from generic concrete blocks led to a 20% decrease in the produced concrete’s strength performance. On the other hand, using recycled aggregates made from the demolition waste led to a smaller decrease in the concrete’s performance: about 8%. The results indicate that with adequate management and prior treatment, the waste from these plants can be re-incorporated into their production processes. If concrete waste is re-used, concrete production, in general, becomes more sustainable for two reasons: less waste ends up as landfill and the consumption of natural aggregates is also reduced.