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The availability of low-cost alternatives to electronic grade silicon has been and still is the condition for the extensive use of photovoltaics as an efficient sun harvesting system. The first step towards this objective was positively carried out in the 1980s and resulted in the reduction in cost and energy of the growth process using as feedstock electronic grade scraps and a variety of solidification procedures, all of which deliver a multi-crystalline material of high photovoltaic quality. The second step was an intense R&D activity aiming at defining and developing at lab scale a new variety of silicon, called “solar grade” silicon, which should fulfil the requirement of both cost effectiveness and high conversion efficiency. The third step involved and still involves the development of cost-effective technologies for the manufacture of solar grade silicon, in alternative to the classical Siemens route, which relays, as is well-known, to the pyrolitic decomposition of high-purity trichlorosilane and which is, also in its more advanced versions, extremely energy intensive. Aim of this paper is to give the author’s viewpoint about some open questions concerning bulk solar silicon for PV applications and about challenges and chances of novel feedstocks of direct metallurgical origin.

Aim of this book is to focus on the properties of defects in semiconductors of the fourth group under a physico-chemical approach, capable to demonstrate whether the full acknowledgement of their chemical nature could account for several problems encountered in practice or would suggest further experimental or theoretical accomplishments.

Magnetic domain walls (DWs) in nanostructures are low-dimensional objects that separate regions with uniform magnetisation. Since they can have different shapes and widths, DWs are an exciting playground for fundamental research and became in the past years the subject of intense works, mainly focused on controlling, manipulating and moving their internal magnetic configuration. In nanostrips with in-plane magnetisation, two DWs have been identified: in thin and narrow strips, transverse walls are energetically favored, while in thicker and wider strips vortex walls have lower energy. The associated phase diagram is now well established and often used to predict the low-energy magnetic configuration in a given magnetic nanostructure. However, besides the transverse and vortex walls, we find numerically that another type of wall exists in permalloy nanostrips. This third type of DW is characterised by a three-dimensional, flux closure micromagnetic structure with an unusual length and three internal degrees of freedom. Magnetic imaging on lithographically-patterned permalloy nanostrips confirms these predictions and shows that these DWs can be moved with an external magnetic field of about 1 mT. An extended phase diagram describing the regions of stability of all known types of DWs in permalloy nanostrips is provided.

Control of magnetization in ferromagnetic metals can be achieved through the spin torque of currents of spin-polarized electrons, usually injected externally. It is now shown that even without this spin-polarized injection, a current can induce strong spin torques through the Rashba effect. The efficiency of this process makes it a realistic candidate for room-temperature spintronic applications. Methods to manipulate the magnetization of ferromagnets by means of local electric fields 1 , 2 , 3 or current-induced spin transfer torque 4 , 5 , 6 allow the design of integrated spintronic devices with reduced dimensions and energy consumption compared with conventional magnetic field actuation 7 , 8 . An alternative way to induce a spin torque using an electric current has been proposed based on intrinsic spin–orbit magnetic fields 9 , 10 and recently realized in a strained low-temperature ferromagnetic semiconductor 11 . Here we demonstrate that strong magnetic fields can be induced in ferromagnetic metal films lacking structure inversion symmetry through the Rashba effect. Owing to the combination of spin–orbit and exchange interactions, we show that an electric current flowing in the plane of a Co layer with asymmetric Pt and AlO x interfaces produces an effective transverse magnetic field of 1 T per 10 8  A cm −2 . Besides its fundamental significance, the high efficiency of this process makes it a realistic candidate for room-temperature spintronic applications.

Although magnetic domain walls could one day be used for information storage, the current challenges to their use are the irreproducibility of their displacement and the limits to their maximum speed. It is now shown that the Rashba effect can be used to provide a solution to both these issues. The propagation of magnetic domain walls induced by spin-polarized currents 1 , 2 , 3 , 4 , 5 has launched new concepts for memory and logic devices 6 , 7 , 8 . A wave of studies focusing on permalloy (NiFe) nanowires 9 has found evidence for high domain-wall velocities (100 m s −1 ; refs  10 , 11 ), but has also exposed the drawbacks of this phenomenon for applications. Often the domain-wall displacements are not reproducible 12 , their depinning from a thermally stable position is difficult 13 and the domain-wall structural instability (Walker breakdown 14 , 15 ) limits the maximum velocity 10 . Here, we show that the combined action of spin-transfer and spin–orbit torques offers a comprehensive solution to these problems. In an ultrathin Co nanowire, integrated in a trilayer with structural inversion asymmetry (SIA), the high spin-torque efficiency 16 facilitates the depinning and leads to high mobility, while the SIA-mediated Rashba field 17 , 18 , 19 controlling the domain-wall chirality stabilizes the Bloch domain-wall structure. Thus, the high-mobility regime is extended to higher current densities, allowing domain-wall velocities up to 400 m s −1 .

microRNAs (miRNAs) are relevant in the pathogenesis of primary myelofibrosis (PMF) but our understanding is limited to specific target genes and the overall systemic scenario islacking. By both knowledge-based and ab initio approaches for comparative analysis of CD34+ cells of PMF patients and healthy controls, we identified the deregulated pathways involving miRNAs and genes and new transcriptional and post-transcriptional regulatory circuits in PMF cells. These converge in a unique and integrated cellular process, in which the role of specific miRNAs is to wire, co-regulate and allow a fine crosstalk between the involved processes. The PMF pathway includes Akt signaling, linked to Rho GTPases, CDC42, PLD2, PTEN crosstalk with the hypoxia response and Calcium-linked cellular processes connected to cyclic AMP signaling. Nested on the depicted transcriptional scenario, predicted circuits are reported, opening new hypotheses. Links between miRNAs (miR-106a-5p, miR-20b-5p, miR-20a-5p, miR-17-5p, miR-19b-3p and let-7d-5p) and key transcription factors (MYCN, ATF, CEBPA, REL, IRF and FOXJ2) and their common target genes tantalizingly suggest new path to approach the disease. The study provides a global overview of transcriptional and post-transcriptional deregulations in PMF, and, unifying consolidated and predicted data, could be helpful to identify new combinatorial therapeutic strategy. Interactive PMF network model: http://compgen.bio.unipd.it/pmf-net/ .

We have used time-resolved x-ray magnetic circular dichroism combined with photoemission electron microscopy (XMCD-PEEM) to investigate the layer-resolved microscopic magnetization reversal in FeNi/X/Co (with X=Cu, Al 2 O 3 ) trilayer systems. These measurements were performed in pump-probe mode, synchronizing magnetic pulses with synchrotron x-ray pulses. The good magnetic contrast observed for most samples reveals that in many cases the magnetization reversal is reproducible. We have used the measurements to obtain domain wall propagation speeds as a function of applied magnetic field, and to investigate the influence of domain wall interactions on the magnetic switching.

Abstract Background Access to quality Home Palliative Care (HPC) is a public health priority. This study analyzed HPC services in Piedmont, a large, diverse Italian region (4.3 million inhabitants), as a case study to understand organizational variations in complex settings and inform equity-focused policies. Methods A cross-sectional survey covered Piedmont's 12 Local Health Authorities (LHAs) and 35 districts. Pre-pandemic data for 2019 were collected in 2023 via in-person questionnaires and interviews with HPC managers/directors. Key structural, process, and outcome indicators were analyzed descriptively. 2022 data were collected for comparison. Results Substantial heterogeneity was found across LHAs in 2019. Formal Local Palliative Care Networks existed in only 8/12 LHAs. Dedicated HPC units were present in 11/12 LHAs, but with varying structures and staffing (physician Full-Time Equivalents, or FTEs, range 0.59-3.00 per 100,000 inhabitants; regional average 1.71, below standards). Nurse FTE data faced challenges. Care pathways showed fragmentation and coordination with emergency services were limited, but psychological support was guaranteed. Large disparities emerged in care intensity (ratio of actual assistance days to total care days range 0.09-0.64) and place of death for cancer patients (home deaths range 6.26%-44.03%). Fragmented data systems hindered monitoring. The 2019-2022 comparison showed improvements (hospital deaths decreased from 23.6% to 16.0%) but confirmed persistent heterogeneity. Conclusions Mapping revealed marked variability in Piedmont's HPC organization, resourcing, delivery, and outcomes. Key challenges identified include network gaps, resource disparities (esp. physicians), fragmented models/pathways, poor care continuity, and inadequate monitoring. Addressing these disparities requires understanding a complex, often poorly documented system lacking systematic data. This study offers a valuable methodology applicable in similar contexts. Key messages • Mapping regional Home Palliative Care reveals significant disparities in organization, resources, and outcomes, impacting equity of access and quality. • Detailed regional analysis provides an evidence base for targeted policies and standardized improvements towards equitable, high-quality HPC across Europe.

This study examines the sedimentary and microbial responses offshore the Marche Region (Italy) to the September 2022 flood, one of the most severe recent hydrological events, which delivered large amounts of sediment and anthropogenic contaminants to the Adriatic Sea. We employed a multidisciplinary approach integrating sedimentology, geochemistry, organic matter analysis, pollutant assessments (Polycyclic Aromatic Hydrocarbons, PAHs and Poly- and Perfluorinated alkyl substances, PFASs), and benthic microbial community structure. Sediments collected just five days after the event offshore river mouths reveal that flood deposits, ranging from fine sand to coarse silt, remained substantially confined to the nearshore zone, whereas finer clay particles were dispersed further offshore and down to the 15 m isobath. This distribution reflects intense riverine inputs and a brief windstorm-enhanced coastal circulation that generated patchy, temporary sediment accumulations mainly in the prodelta sector. Simultaneously, the flood forced a strong spatial heterogeneity in benthic bacterial communities, through the introduction of short-distance shifts in sediment texture and organic matter content. Freshwater taxa became prominent in prodelta deposits, highlighting riverine sedimentary imprints. Heavy metal concentrations remained below regulatory thresholds, whereas organic pollutants, heterogeneously distributed, reach peak concentrations offshore urban and industrial zones. PAH signatures indicate mixed pyrogenic and petrogenic sources, while next-generation PFASs (6:2 FTS) showed localized but severe contamination linked to upstream industrial activities. Despite the flood's magnitude onshore, its offshore sedimentary signatures resulted ephemeral and spatially limited. These findings underscore the ecological significance of episodic sediment and contaminant input, while highlighting the challenges in detecting such transient events in the marine stratigraphic record.