Publications by authors named "Davide Mariotti"

This study provides a systematic and comprehensive investigation of the transformation process of copper-based metal-organic frameworks (Cu-BTC MOFs) into nanoporous copper oxides (P-CuO) through controlled calcination. While calcination is a well-established method for producing MOF-derived oxides, previous studies have primarily focused on their applications. Most of them often lack detailed exploration of the transformation process and decomposition mechanisms though it is crucial for achieving tunability in MOF-derived structures.

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We present the formation of a composite film made out of formamidinium lead iodide (FAPI) and molybdenum disulphide quantum dots (MoS QDs) and propose a corresponding photovoltaic device architecture based on a 'type-I' alignment of the two materials' electronic energy levels. The introduction of the MoS QDs has not compromised the overall crystallinity of the FAPI film and the composite absorber has shown improved stability. We report on the benefits of this composite film and energy band arrangement as the photogenerated carriers in MoS QDs, both positive and negative, are injected into the FAPI host matrix, resulting in an increased current density of 24.

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Creating tin-alloyed silicon nanocrystals with tailored bandgap values is a significant challenge, primarily because a substantial concentration of tin is essential to observe useful changes in the electronic structure. However, high concentration of Sn leads to instability of the silicon-tin nanocrystals. This work introduces a completely new approach to doping and the modification of the electronic structure of nanoparticles by incorporating few-atom clusters in nanocrystals, deviating from isolated atom doping or attempting alloying.

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  • Researchers developed a new low-temperature plasma-assisted method to create GdFeO nanoparticles from solid metallic foils of Gd and Fe, enabling both colloidal and thin film forms.
  • Characterization techniques like electron microscopy and spectroscopy confirmed the successful formation of the orthorhombic perovskite GdFeO phase and a uniform distribution of elements.
  • The nanoparticles displayed properties typical of antiferromagnetic materials, with potential applications in magnetic memory devices and gas sensors facilitated by a modified one-step thin film deposition process.
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  • The study focused on the effectiveness of tixagevimab/cilgavimab (T/C) as pre-exposure prophylaxis (PrEP) in immunocompromised individuals, categorizing them into groups based on their COVID-19 history.
  • A total of 231 participants were included, with a significant portion having hematological diseases and receiving multiple vaccine doses; breakthrough infections (BTIs) occurred in 56 participants (24%) but were mostly mild to moderate.
  • Immune markers were measured over time, showing an initial increase in anti-RBD IgG antibodies at 3 months, a decline at 6 months, and low neutralizing antibodies, reinforcing T/C's clinical efficacy in reducing severe COVID-19
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  • Exsolution of metal nanoparticles from perovskite oxides is an effective method for creating catalyst-support systems, but traditional methods require high temperatures and long processing times.* -
  • Plasma direct exsolution offers a breakthrough by enabling the extraction of nickel nanoparticles at room temperature and atmospheric pressure, taking only minutes to complete.* -
  • Experiments show that the exsolved nanoparticles demonstrate good catalytic performance in reactions like methanation and oxidation, indicating that this low-temperature technique could enhance the practical use of catalyst systems.*
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  • This study looked at how well people with HIV responded to a COVID-19 booster shot, focusing on their fight against different virus versions (XBB sublineages).
  • It found that some people didn't have a strong response 15 days after the shot, and that the protection got weaker over time, especially over 6 months.
  • The researchers suggested that to better protect people with HIV in the future, a new vaccine specifically for a virus version called XBB.1.5 should be used.
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This study examines the effect of quantum confinement and surface orientations on the electronic properties of NiO quantum dots. It compares NiO nanocrystals produced via atmospheric-pressure microplasma and femtosecond laser (fs-laser) ablation in water, finding that both methods yield quantum-confined nanocrystals with a defined face-centered cubic lattice. Notably, fs-laser synthesis generates crystalline nanocrystals from both crystalline and amorphous targets.

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Progress in electrochemical water-splitting devices as future renewable and clean energy systems requires the development of electrodes composed of efficient and earth-abundant bifunctional electrocatalysts. This study reveals a novel flexible and bifunctional electrode () by hybridizing macroscopically assembled carbon nanotube ribbons () and atmospheric plasma-synthesized NiO quantum dots (QDs) with varied loadings to demonstrate bifunctional electrocatalytic activity for stable and efficient overall water-splitting (OWS) applications. Comparative studies on the effect of different electrolytes, e.

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  • * The most effective method was heating at 70 °C, which decreased MPXV titer significantly, while Triton X-100 was the least effective.
  • * While UV-C and heat effectively reduced MPXV infectiousness, they negatively affected the detection of MPXV DNA and proteins, highlighting a trade-off in sample handling procedures.
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  • The study investigates the decline of immune responses in people living with HIV (PLWH) after vaccination and booster doses, focusing on those with low CD4 counts (≤200 cells/mm).
  • It measured neutralizing antibodies and T cell responses at multiple time points to assess the effectiveness of the primary vaccine cycle and booster dose.
  • Results showed that those with low CD4 counts experienced a more significant drop in neutralizing antibodies, but booster doses increased these levels and maintained them longer against certain variants, even though T cell responses remained detectable across all groups.
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An atmospheric-pressure plasma system is developed and is used to treat carbon nanotube assemblies, producing a hybrid carbon-zinc structure. This system is integrated into a floating-catalyst chemical vapor deposition furnace used for the synthesis of macroscopic assemblies of carbon nanotubes to allow for the in-line, continuous, and single-step production of nano-composite materials. Material is deposited from a sacrificial zinc wire in the form of nanoparticles and can coat the surface of the individual carbon nanotubes as they form.

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The design and fabrication of eco-friendly and cost-effective (photo)electrocatalysts for the oxygen evolution reaction (OER) is a key research goal for a proper management of water splitting to address the global energy crisis. In this work, we focus on the preparation of supported MnO/graphitic carbon nitride (g-CN) OER (photo)electrocatalysts by means of a novel preparation strategy. The proposed route consists of the plasma enhanced-chemical vapor deposition (PE-CVD) of MnO nanoarchitectures on porous Ni scaffolds, the anchoring of controllable g-CN amounts by an amenable electrophoretic deposition (EPD) process, and the ultimate thermal treatment in air.

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Objectives: To investigate immunogenicity of SARS-CoV-2 vaccine third booster dose (3BD; fifth dose) with bivalent vaccine original/BA4/5 vaccine in people living with HIV (PLWH).

Methods: This is an observational cohort study to evaluate the outcomes of SARS-CoV-2 vaccination (HIV-VAC study). We analyzed microneutralization assay and interferon-γ production in 48 PLWH on antiretroviral therapy with clusters of differentiation (CD4) count <200 cell/mm and/or previous AIDS according to immunization status: vaccinated PLWH who had a previous SARS-CoV-2 infection (hybrid immunization, HI) vs those only vaccinated (non-hybrid immunization, nHI) and current CD4 count.

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Nanocrystals have a great potential for future materials with tunable bandgap, due to their optical properties that are related with the material used, their sizes and their surface termination. Here, we concentrate on the silicon-tin alloy for photovoltaic applications due to their bandgap, lower than bulk Si, and also the possibility to activate direct band to band transition for high tin concentration. We synthesized silicon-tin alloy nanocrystals (SiSn-NCs) with diameter of about 2-3 nm by confined plasma technique employing a femtosecond laser irradiation on amorphous silicon-tin substrate submerged in liquid media.

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  • * The effectiveness of these nanofluids relies on their high stability and performance under various conditions, which is crucial for practical applications in solar energy systems.
  • * This review explores recent advancements in nanofluid development, including preparation methods, performance metrics, and stability assessments, while also addressing challenges and future prospects for their use in solar collectors.
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We discuss the electronic properties of quantum-confined nanocrystals. In particular, we show how, starting from the discrete molecular states of small nanocrystals, an approximate band structure (quasi-band structure) emerges with increasing particle size. Finite temperature is found to broaden the discrete states in energy space forming even for nanocrystals in the quantum-confinement regime quasi-continuous bands in k-space.

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Background: Lymphopenia, particularly when restricted to the T-cell compartment, has been described as one of the major clinical hallmarks in patients with coronavirus disease 2019 (COVID-19) and proposed as an indicator of disease severity. Although several mechanisms fostering COVID-19-related lymphopenia have been described, including cell apoptosis and tissue homing, the underlying causes of the decline in T-cell count and function are still not completely understood.

Objective: Given that viral infections can directly target thymic microenvironment and impair the process of T-cell generation, we sought to investigate the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on thymic function.

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  • In a study on peritoneal fibrosis, the HDAC inhibitor MS-275 was found to promote the expression of miR-769-5p, which can reverse mesothelial to mesenchymal transition (MMT) and reduce the invasive properties of mesothelial cells.
  • The transcription factor Wilms' tumor 1 (WT1) was identified as a key regulator that enhances miR-769-5p expression after HDAC1 inhibition, indicating a complex interplay in cellular communication that could impact treatment strategies for fibrosis. *
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Localized surface plasmon resonance (LSPR) of metallic nanostructures is a unique phenomenon that controls the light in sub-wavelength volumes and enhances the light-matter interactions. Traditionally, the excitation and measurement of LSPR require bulky external light sources, and efforts to scale down to nano-plasmonic devices have predominantly relied on the system's miniaturization and associated accessories. Addressing this, here we show the generation and detection of LSPR wavelength (λ) shifts in large-area nanostructured Au surfaces using frictional charges generated by triboelectric surfaces.

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Ferroic domain dynamics, as a function of external stimuli, can be collectively described as scale-invariant avalanches characterised by a critical exponent that are sensitive to the complexity of the domain microstructure. The understanding and manipulation of these avalanches lies at the heart of developing novel applications such as neuromorphic computing. Here we combine in situ heating optical observations and mean-field analysis to investigate the collective domain behaviour in pure-ferroelastic lanthanum aluminate (LaAlO[Formula: see text]) as a function of aspect ratio, the ratio of sample length to width, where the movement of the domains is predominantly driven by thermal stresses via thermal expansion/contraction during heat cycling.

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