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The Jinc- function: a note on the relevant generalizations and applications
Full text linkJinc and sinc-functions are well known special functions with important applications in Spectral theory, Fourier Optics and diffraction problems from circular apertures. The first are less widely known than the latter and should be more properly framed within the context of special functions. In this article, we present a unified point of view to the relevant generalizations, propose generalized forms and touch on application perspectives
Characterization of patient-derived intestinal organoids for modelling fibrosis in Inflammatory Bowel Disease
Full text linkBackground and aims: Intestinal fibrosis is a common complication of Inflammatory Bowel Disease (IBD), namely Crohn's disease (CD) and ulcerative colitis (UC), but the precise mechanism by which it occurs is incompletely understood hampering the development of effective therapeutic strategies. Here, we aimed at inducing and characterizing an inflammation-mediated fibrosis in patient-derived organoids (PDOs) issued from crypts isolated from colonic mucosal biopsies of IBD pediatric patients and age matched-control subjects (CTRLs). Methods: Inflammatory-driven fibrosis was induced by exposing CTRL-, CD- and UC-PDOs to the pro-inflammatory cytokine TNF-α for one day, followed by a co-treatment with TNF-α and TGF-β1 for three days. Fibrotic response was proven by analyzing inflammatory and fibrotic markers by RT-qPCR and immunofluorescence. Transcriptomic changes were assessed by RNA-sequencing. Results: Co-treatment with TNF-α and TGF-β1 caused in CTRL- and IBD-PDOs morphological changes towards a mesenchymal-like phenotype and up-regulation of inflammatory, mesenchymal, and fibrotic markers. Transcriptomic profiling highlighted that in all intestinal PDOs, regardless of the disease, the co-exposure to TNF-α and TGF-β1 regulated EMT genes and specifically increased genes involved in positive regulation of cell migration. Finally, we demonstrated that CD-PDOs display a specific response to fibrosis compared to both CTRL- and UC-PDOs, mainly characterized by upregulation of nuclear factors controlling transcription. Conclusions: This study demonstrates that intestinal PDOs may develop an inflammatory-derived fibrosis thus representing a promising tool to study fibrogenesis in IBD. Fibrotic PDOs show increased expression of EMT genes. In particular, fibrotic CD-PDOs display a specific gene expression signature compared to UC and CTRL-PDOs
W-HYDRA: a new experimental platform for the Water-Cooled Lead Lithium Breeding Blanket
Full text linkIn the framework of the activities coordinated by the EUROfusion consortium, the Water thermal-HYDRAulic (W-HYDRA) experimental platform is being built at the ENEA Brasimone Research Centre in order to support the development of the Water-Cooled Lead Lithium (WCLL) Breeding Blanket (BB). In particular, this infrastructure will make possible the installation and testing of prototypical mock-ups under relevant working conditions, such as the First Wall (FW), the manifold and the Steam Generator (SG). Moreover, it will represent an integral test facility for the investigation of phenomena characteristic of WCLL BB concept, such as the PbLi/water interaction. Finally, the collection of data coming from the different planned experimental campaigns will allow to qualify and validate numerical models and codes currently adopted for the design of components, as well as for the modelling of complex phenomena typical of the WCLL BB. In order to come to a definitive design of the different facilities constituting the experimental platform, several design analyses assessing the thermal, hydraulic and structural performances of the different facilities and components are necessary. The paper reports a highlight of the W-HYDRA platform with a general description of the facilities. Some of the most relevant design studies carried out so far are reported as well, highlighting their impact on the evolution of the design
Isolation of biocrust cyanobacteria and evaluation of Cu, Pb, and Zn immobilisation potential for soil restoration and sustainable agriculture
Full text linkSoil contamination by heavy metals represents an important environmental and public health problem of global concern. Biocrust-forming cyanobacteria offer promise for heavy metal immobilisation in contaminated soils due to their unique characteristics, including their ability to grow in contaminated soils and produce exopolysaccharides (EPS). However, limited research has analysed the representativeness of cyanobacteria in metal-contaminated soils. Additionally, there is a lack of studies examining how cyanobacteria adaptation to specific environments can impact their metal-binding capacity. To address this research gap, we conducted a study analysing the bacterial communities of cyanobacteria-dominated biocrusts in a contaminated area from South Sardinia (Italy). Additionally, by using two distinct approaches, we isolated three Nostoc commune strains from cyanobacteria-dominated biocrust and we also evaluated their potential to immobilise heavy metals. The first isolation method involved acclimatizing biocrust samples in liquid medium while, in the second method, biocrust samples were directly seeded onto agar plates. The microbial community analysis revealed Cyanobacteria, Bacteroidota, Proteobacteria, and Actinobacteria as the predominant groups, with cyanobacteria representing between 13.3 % and 26.0 % of the total community. Despite belonging to the same species, these strains exhibited different growth rates (1.1–2.2 g L−1 of biomass) and capacities for EPS production (400–1786 mg L−1). The three strains demonstrated a notable ability for metal immobilisation, removing up to 88.9 % of Cu, 86.2 % of Pb, and 45.3 % of Zn from liquid medium. Cyanobacteria EPS production showed a strong correlation with the removal of Cu, indicating its role in facilitating metal immobilisation. Furthermore, differences in Pb immobilisation (40–86.2 %) suggest possible environmental adaptation mechanisms of the strains. This study highlights the promising application of N. commune strains for metal immobilisation in soils, offering a potential bioremediation tool to combat the adverse effects of soil contamination and promote environmental sustainability
Towards Complex Tissues Replication: Multilayer Scaffold Integrating Biomimetic Nanohydroxyapatite/Chitosan Composites
Full text linkThis study explores an approach to design and prepare a multilayer scaffold mimicking interstratified natural tissue. This multilayer construct, composed of chitosan matrices with graded nanohydroxyapatite concentrations, was achieved through an in situ biomineralization process applied to individual layers. Three distinct precursor concentrations were considered, resulting in 10, 20, and 30 wt% nanohydroxyapatite content in each layer. The resulting chitosan/nanohydroxyapatite (Cs/n-HAp) scaffolds, created via freeze-drying, exhibited nanohydroxyapatite nucleation, homogeneous distribution, improved mechanical properties, and good cytocompatibility. The cytocompatibility analysis revealed that the Cs/n-HAp layers presented cell proliferation similar to the control in pure Cs for the samples with 10% n-HAp, indicating good cytocompatibility at this concentration, while no induction of apoptotic death pathways was demonstrated up to a 20 wt% n-Hap concentration. Successful multilayer assembly of Cs and Cs/n-HAp layers highlighted that the proposed approach represents a promising strategy for mimicking multifaceted tissues, such as osteochondral ones
Unravelling Recent Advances in Ionizing Irradiation-Based Management of Post-Harvest Crop Losses: a Pan-Global Survey
No full textPostharvest disease is a pivotal issue worldwide that causes notable losses of vegetables and fruits. Although a variety of treatments exist for the control of pathogen-induced postharvest losses, it is imperative to develop more eco-friendly and less hazardous replacements to reduce the risks to the environment. Ionizing radiation, a productive nonthermal approach, is considered an additional promising alternative to pre-existing chemicals. However, irradiation singularly cannot be as efficacious as a fungicide, and additionally, an overdose results in detrimental impacts on the physical attributes of the produce. Thus, combined treatments can be proficiently utilized to augment the efficiency and consistency of these treatments against postharvest diseases, thereby providing a potential approach. Although a surplus quantity of fruits and vegetables undergo irradiation treatment every year to regulate postharvest diseases, the use of irradiation is debatable, as it is rarely accepted by consumers and industries. This review addresses the probable modes of action of ionizing radiation, the factors affecting the susceptibility of pathogens, and the impacts of combined treatments involving other physical, chemical, and biological methods
Approximate calculation of backpropagated energy spectrum for a proton beam
Full text linkIn certain experimental setups used for proton irradiations at the TOP-IMPLART linear accelerator at the ENEA Frascati Center, the energy spectrum of the proton beam is measured at the end of a propagation path, which includes transmission through different materials, such as air, windows, slabs, etc. In this paper, we develop and test an approximate mathematical method to calculate the energy spectrum at the accelerator exit from such a measured transmitted spectrum. In the first experimental test application, the spectrum measurement exploits the visible photoluminescence of F 2 and F 3 + color centers generated in lithium fluoride crystals by the interaction of the crystal lattice with protons. In the second test application, a simulated measurement of a propagated energy spectrum along a transport line is considered. In principle, the proposed method is applicable to the energy spectra of proton beams measured in any manner
Carbon dioxide valorisation with partial oxidation of methane in a water cooled DBD plasma
Full text linkThe valorisation of carbon dioxide in chemical plasmas implies as a principal reaction step its energy efficient dissociation into carbon monoxide. For hydrogen production, the reaction carbon monoxide with water (WGS) may lead to the generation of green hydrogen and reusable carbon dioxide. Beyond hydrogen, most valorisation processes require the removal of O2 to avoid its recombination with CO on any downstream hot catalytic surface. Moreover, if the oxygen scavenging is performed directly inside the plasma volume, it can also shift the dissociation equilibrium that is responsible for the well-known trade-off between energy efficiency and conversion, thus improving efficiency when larger specific energy densities are applied. In this paper we first report on the plasma dissociation of pure CO2 in a water cooled, high power(<2 kW), Dielectric Barrier Discharge with high gas flow regime (<3600sccm), and then we explore the synergistic oxygen removal by the partial oxidation of methane for syngas production. The presence of CH4, even in small amounts, removes oxygen from the outstream and from the discharge region, as confirmed by mass and optical emission spectroscopies, and enhances the process in two ways: it allows to feed the system with gas having a low CH4 to CO2 ratio (0.1–0.3) instead of pure CO2, where landfill and waste gases are undesired climate altering emissions with a similar composition that currently require flaring; it will allow to use directly the reactor outstream into a WGS reactor, or any other CO valorisation process without the necessity to remove downstream O2
Insights from applications of the RSTM tool for coupled CFD-activation fluid simulation
No full textAccurate prediction of the activation of fluids flowing under irradiation is important for the timely development of fusion technology. One of the major current issues is the cooling water of ITER, which becomes activated by plasma neutrons during nuclear operations, thus raising a number of radiological implications such as radiation effects on sensitive equipment, compliance with radiological protection zoning, and compliance with radioactivity limits in regulations of pressure equipment and effluents. Further significant applications are the activation of other service fluids in ITER and of the LiPb in both ITER and DEMO breeding blanket modules. To avoid systematic uncertainties, simulation of the activation of fluids flowing in arbitrarily complex 3D geometry, flow regimes and neutron fields requires full coupling of activation with fluid-dynamics physics models. No such tools were available until recently: the Radio-Species Transport Model (RSTM), based on the well-established ANSYS Fluent® UDS methodology, is one conceived and developed at F4E. Here we review the methodology and capabilities of the RSTM, as well as earlier development, validation, benchmarking and application activities. We then report currently ongoing further applications and benchmarking being performed in collaboration with specific tasks of the EUROFusion programme Preparation for ITER Operation. Computations, results and comparison with other methodologies for several cases of interest are presented and discussed
Electrodeposition of Iron Selenide Films: Electrochemical and Morphological Characterizations
No full textIn recent years, iron-based superconductors have attracted attention due to their interesting electromagnetic properties that open wide application prospects. Among these, FeSe is particularly studied since it is both a superconductor with a bulk critical transition temperature, Tc, of 8 K and a semiconductor used in solar cells. For the design of an iron-based superconductor, the preparation of larger samples is envisaged, and the possibility of maintaining low manufacturing costs is extremely appealing. One possible technique suitable for this purpose is electrodeposition, which combines inexpensive equipment to the easy scaling towards larger/longer samples. In this work, we study the possibility of using electrodeposition as a method for FeSe film growth. We start by analyzing the electrochemical behaviour of the precursor solution via cyclic voltammetry before attempting electrodeposition. We find out that the main drawback of this technique is the microstructure of the deposited film, which is made mostly of unconnected grains. This issue does not rule out this technique for the preparation of superconducting thin films, but it has to be addressed in view of a potential application of this technique to the preparation of an iron-based coated conductor