Sustainability and resilience after COVID-19: A circular premium in the fashion industry

COVID-19 has challenged so many of humanity’s certainties, but it has also shown that we are able to react to serious threats. Moreover, it is possible to see a great opportunity: to create a real, sustainable renaissance. However, the challenge is so complex that it requires the involvement of as many categories of stakeholders as possible, and the implementation of low-carbon models in different production sectors [1]. A single closed-loop supply chain can be reconfigured as a multi-loop system, in which both reused and recycled materials from a previous life cycle are reintroduced into the market as new products and values. In particular, this editorial focuses on on the fashion industry, which unquestionably characterizes the lives of all citizens and identifies a potential circular premium

Predicting the thermodynamics by using state-dependent interactions

We reconsider the structure-based route to coarse graining in which the coarse-grained model is defined in such a way to reproduce some distributions functions of the original system as accurately as possible. We consider standard expressions for pressure and chemical potential applied to this family of coarse-grained models with density-dependent interactions and show that they only provide approximations to the pressure and chemical potential of the underlying original system. These approximations are then carefully compared in two cases: we consider a generic microscopic system in the low-density regime and polymer solutions under good-solvent conditions. Moreover, we show that the state-dependent potentials depend on the ensemble in which they have been derived. Therefore, care must be used in applying canonical state-dependent potentials to predict phase lines, which is typically performed in other ensembles.Comment: 29 pages, 1 figure; To appear in J. Chem. Phy

Circular manufacturing ecosystems: Automotive printed circuit boards recycling as an enabler of the economic development

ABSTRACTThe management of waste from electrical and electronic equipments (WEEEs) is a well-established topic in the extant literature. However, also the automotive sector is becoming a relevant source of WEEE, given the even more relevant presence of electronic components in cars. Due to new European environmental policies, end-of-life vehicles (ELVs) volumes are expected to grow in the next future, together with obsolete car electronics components. Hence, this work wants to assess the potential economic impact derived from car electronics recycling processes adopting the Net Present Value (NPV) as reference indicator. Through a detailed sensitivity and break-even point (BEP) analysis and a comparison of different cases, this work identifies a set of scenarios useful for industrial actors willing to enter the market of car electronics recycling. Results show an NPV varying from 136,570 to 607,621 €/t with a decisive role played by gold recovery

CFD-3D and 1D modeling of fuel cell powertrain for a hydrogen vehicle

As it is known the transport sector represents a major contributor to climate change. In particular, private transport contributes to the degradation of the air quality inside the cities or the residential areas. To address this issue, a progressive reduction of the use of fossil fuels as a primary energy source for these vehicles and the promotion of cleaner powertrain alternatives is in order. This study focuses on designing a fuel cell powertrain for a hydrogen-powered passenger car using numerical modeling. To this purpose, we initially modeled a base fuel cell and optimized its performance by using various materials for the bipolar plates and adjusting the platinum loading between the anode and cathode. Then, a preliminary design of the new powertrain has been proposed in order to achieve a nominal power of 100 kW and it has been tested on a WLTP 3b homologation cycle. Finally, we have been able to numerically estimate the behavior of the three main feeding line: hydrogen line, air line and cooling line. In conclusion, the obtained results demonstrate how numerical modelling can be successfully used in the design of complex systems such as those related to alternative energy. This work also provides a solid basis for the future development of increasingly efficient and environmentally friendly hydrogen vehicles

Polymers as compressible soft spheres

We consider a coarse-grained model in which polymers under good-solvent conditions are represented by soft spheres whose radii, which should be identified with the polymer radii of gyrations, are allowed to fluctuate. The corresponding pair potential depends on the sphere radii. This model is a single-sphere version of the one proposed in Vettorel et al., Soft Matter 6, 2282 (2010), and it is sufficiently simple to allow us to determine all potentials accurately from full-monomer simulations of two isolated polymers (zero-density potentials). We find that in the dilute regime (which is the expected validity range of single-sphere coarse-grained models based on zero-density potentials) this model correctly reproduces the density dependence of the radius of gyration. However, for the thermodynamics and the intermolecular structure, the model is largely equivalent to the simpler one in which the sphere radii are fixed to the average value of the radius of gyration and radiiindependent potentials are used: for the thermodynamics there is no advantage in considering a fluctuating sphere size.Comment: 21 pages, 7 figure

Three-Dimensional CFD Simulation of a Proton Exchange Membrane Electrolysis Cell

The energy shift towards carbon-free solutions is creating an ever-growing engineering interest in electrolytic cells, i.e., devices to produce hydrogen from water-splitting reactions. Among the available technologies, Proton Exchange Membrane (PEM) electrolysis is the most promising candidate for coping with the intermittency of renewable energy sources, thanks to the short transient period granted by the solid thin electrolyte. The well-known principle of PEM electrolysers is still unsupported by advanced engineering practices, such as the use of multidimensional simulations able to elucidate the interacting fluid dynamics, electrochemistry, and heat transport. A methodology for PEM electrolysis simulation is therefore needed. In this study, a model for the multidimensional simulation of PEM electrolysers is presented and validated against a recent literature case. The study analyses the impact of temperature and gas phase distribution on the cell performance, providing valuable insights into the understanding of the physical phenomena occurring inside the cell at the basis of the formation rate of hydrogen and oxygen. The simulations regard two temperature levels (333 K and 353 K) and the complete polarization curve is numerically predicted, allowing the analysis of the overpotentials break-up and the multi-phase flow in the PEM cell. An in-house developed model for macro-homogeneous catalyst layers is applied to PEM electrolysis, allowing independent analysis of overpotentials, investigation into their dependency on temperature and analysis of the cathodic gas–liquid stratification. The study validates a comprehensive multi-dimensional model for PEM electrolysis, relevantly proposing a methodology for the ever-growing urgency for engineering optimization of such devices

Episodic ataxia type 1

Clinical characteristics: Episodic ataxia type 1 (EA1) is a potassium channelopathy characterized by constant myokymia and dramatic episodes of spastic contractions of the skeletal muscles of the head, arms, and legs with loss of both motor coordination and balance. During attacks individuals may experience a number of variable symptoms including vertigo, blurred vision, diplopia, nausea, headache, diaphoresis, clumsiness, stiffening of the body, dysarthric speech, and difficulty in breathing, among others. EA1 may be associated with epilepsy. Other findings can include delayed motor development, cognitive disability, choreoathetosis, and carpal spasm. Usually, onset is in childhood or early adolescence. Diagnosis/testing: Diagnosis is based on clinical findings, an electrophysiologic test of axonal superexcitability and threshold electrotonus, and/or molecular genetic testing of KCNA1, the only gene in which pathogenic variants are known to cause EA1. Management: Treatment of manifestations: Acetazolamide (ACTZ), a carbonic-anhydrase (CA) inhibitor, may reduce the frequency and severity of the attacks in some but not all affected individuals. Antiepileptic drugs (AEDs) may significantly reduce the frequency of the attacks in some individuals.peer-reviewe

Induced pluripotent stem cell-based models: Are we ready for that heart in a dish?

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A Retrospective Analysis of Vinorelbine Chemotherapy for Patients With Previously Treated Soft-Tissue Sarcomas

Introduction. The role of vinorelbine in specific soft tissue sarcoma subtypes is unclear. We present retrospective single institution experience with single-agent vinorelbine in subjects with metastatic soft tissue malignancies. Methods. Fifty-eight patients were treated with single agent intravenous vinorelbine between April 1997 and December 2004. Doxorubicin had been administered previously to 53 subjects (91%), and the median number of lines of previous chemotherapy was 3 (range 0–7). Results. Patients received a median 6 doses of vinorelbine (range 1–65). The overall response rate was 6% (3 patients: 1 angiosarcoma, 1 epithelioid sarcoma, and 1 embryonal rhabdomyosarcoma). Fourteen patients (26%) experienced a best result of stable disease. Median time to progression was 1.8 months (95% confidence intervals 1.5–2.1 months, Kaplan-Meier estimate). Eight patients experienced grade 3 or 4 toxicity, most commonly febrile neutropenia. Conclusion. Vinorelbine demonstrates limited activity in a heavily pretreated group of soft-tissue sarcoma patients. Prospective investigation may be considered for selected sarcoma subtypes