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1.
ACS Photonics ; 10(12): 4079-4103, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38145171

RESUMEN

Metasurfaces have recently emerged as a promising technological platform, offering unprecedented control over light by structuring materials at the nanoscale using two-dimensional arrays of subwavelength nanoresonators. These metasurfaces possess exceptional optical properties, enabling a wide variety of applications in imaging, sensing, telecommunication, and energy-related fields. One significant advantage of metasurfaces lies in their ability to manipulate the optical spectrum by precisely engineering the geometry and material composition of the nanoresonators' array. Consequently, they hold tremendous potential for efficient solar light harvesting and conversion. In this Review, we delve into the current state-of-the-art in solar energy conversion devices based on metasurfaces. First, we provide an overview of the fundamental processes involved in solar energy conversion, alongside an introduction to the primary classes of metasurfaces, namely, plasmonic and dielectric metasurfaces. Subsequently, we explore the numerical tools used that guide the design of metasurfaces, focusing particularly on inverse design methods that facilitate an optimized optical response. To showcase the practical applications of metasurfaces, we present selected examples across various domains such as photovoltaics, photoelectrochemistry, photocatalysis, solar-thermal and photothermal routes, and radiative cooling. These examples highlight the ways in which metasurfaces can be leveraged to harness solar energy effectively. By tailoring the optical properties of metasurfaces, significant advancements can be expected in solar energy harvesting technologies, offering new practical solutions to support an emerging sustainable society.

2.
Nanotechnology ; 34(50)2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37738967

RESUMEN

Titanium nitride (TiN) has recently emerged as an alternative to coinage metals to enable the development of integrated plasmonic devices at visible and medium-infrared wavelengths. In this regard, its optical performance can be conveniently tuned by tailoring the process parameters of physical vapor deposition methods, such as magnetron sputtering and pulsed laser deposition (PLD). This review first introduces the fundamental features of TiN and a description on its optical properties, including insights on the main experimental techniques to measure them. Afterwards, magnetron sputtering and PLD are selected as fabrication techniques for TiN nanomaterials. The fundamental mechanistic aspects of both techniques are discussed in parallel with selected case studies from the recent literature, which elucidate the critical advantages of such techniques to engineer the nanostructure and the plasmonic performance of TiN.

3.
ACS Photonics ; 10(9): 3291-3301, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37743938

RESUMEN

We report a quasi-unitary broadband absorption over the ultraviolet-visible-near-infrared range in spaced high aspect ratio, nanoporous titanium oxynitride nanotubes, an ideal platform for several photothermal applications. We explain such an efficient light-heat conversion in terms of localized field distribution and heat dissipation within the nanopores, whose sparsity can be controlled during fabrication. The extremely large heat dissipation could not be explained in terms of effective medium theories, which are typically used to describe small geometrical features associated with relatively large optical structures. A fabrication-process-inspired numerical model was developed to describe a realistic space-dependent electric permittivity distribution within the nanotubes. The resulting abrupt optical discontinuities favor electromagnetic dissipation in the deep sub-wavelength domains generated and can explain the large broadband absorption measured in samples with different porosities. The potential application of porous titanium oxynitride nanotubes as solar absorbers was explored by photothermal experiments under moderately concentrated white light (1-12 Suns). These findings suggest potential interest in realizing solar-thermal devices based on such simple and scalable metamaterials.

4.
ACS Catal ; 13(15): 10205-10216, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37560189

RESUMEN

Large-scale development of electrochemical cells is currently hindered by the lack of Earth-abundant electrocatalysts with high catalytic activity, product selectivity, and interfacial mass transfer. Herein, we developed an electrocatalyst fabrication approach which responds to these requirements by irradiating plasmonic titanium nitride (TiN) nanocubes self-assembled on a carbon gas diffusion layer in the presence of polymeric binders. The localized heating produced upon illumination creates unique conditions for the formation of TiN/F-doped carbon hybrids that show up to nearly 20 times the activity of the pristine electrodes. In alkaline conditions, they exhibit enhanced stability, a maximum H2O2 selectivity of 90%, and achieve a H2O2 productivity of 207 mmol gTiN-1 h-1 at 0.2 V vs RHE. A detailed electrochemical investigation with different electrode arrangements demonstrated the key role of nanocomposite formation to achieve high currents. In particular, an increased TiOxNy surface content promoted a higher H2O2 selectivity, and fluorinated nanocarbons imparted good stability to the electrodes due to their superhydrophobic properties.

5.
ACS Nano ; 17(12): 11427-11438, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37310716

RESUMEN

Nanoscale investigation of the reactivity of photocatalytic systems is crucial for their fundamental understanding and improving their design and applicability. Here, we present a photochemical nanoscopy technique that unlocks the local spatial detection of molecular products during plasmonic hot-carrier-driven photocatalytic reactions with nanometric precision. By applying the methodology to Au/TiO2 plasmonic photocatalysts, we experimentally and theoretically determined that smaller and denser Au nanoparticle arrays present lower optical contribution with quantum efficiency in hot-hole-driven photocatalysis closely related to the population heterogeneity. As expected, the highest quantum yield from a redox probe oxidation is achieved at the plasmon peak. Investigating a single plasmonic nanodiode, we unravel the areas where oxidation and reduction products are evolved with subwavelength resolution (∼200 nm), illustrating the bipolar behavior of such nanosystems. These results open the way to quantitative investigations at the nanoscale to evaluate the photocatalytic reactivity of low-dimensional materials in a variety of chemical reactions.

6.
ACS Appl Mater Interfaces ; 14(16): 18453-18463, 2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35436405

RESUMEN

Broadband absorption of solar light is a key aspect in many applications that involve an efficient conversion of solar energy to heat. Titanium nitride (TiN)-based materials, in the form of periodic arrays of nanostructures or multilayers, can promote significant heat generation upon illumination thanks to their efficient light absorption and refractory character. In this work, pulsed laser deposition was chosen as a synthesis technique to shift metallic bulk-like TiN to nanoparticle-assembled hierarchical oxynitride (TiOxNy) films by increasing the background gas deposition pressure. The nanoporous hierarchical films exhibit a tree-like morphology, a strong broadband solar absorption (∼90% from the UV to the near-infrared range), and could generate temperatures of ∼475 °C under moderate light concentration (17 Suns). The high heat generation achieved by treelike films is ascribed to their porous morphology, nanocrystalline structure, and oxynitride composition, which overall contribute to a superior light trapping and dissipation to heat. These properties pave the way for the implementation of such films as solar absorber structures.

7.
Front Cardiovasc Med ; 9: 1013262, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36684586

RESUMEN

Thrombosis of the lung microvasculature is a characteristic of COVID-19 disease, which is observed in large excess compared to other forms of acute respiratory distress syndrome and thus suggests a trigger for thrombosis that is endogenous to the lung. Our recent work has shown that the SARS-CoV-2 Spike protein activates the cellular TMEM16F chloride channel and scramblase. Through a screening on >3,000 FDA/EMA approved drugs, we identified Niclosamide and Clofazimine as the most effective molecules at inhibiting Spike-induced TMEM16 activation. As TMEM16F plays an important role in stimulating the procoagulant activity of platelets, we investigated whether Spike directly affects platelet activation and pro-thrombotic function and tested the effect of Niclosamide and Clofazimine on these processes. Here we show that Spike, present either on the virion envelope or on the cell plasma membrane, promotes platelet activation, adhesion and spreading. Spike was active as a sole agonist or, even more effectively, by enhancing the function of known platelet activators. In particular, Spike-induced a marked procoagulant phenotype in platelets, by enhancing Ca2+ flux, phosphatidylserine externalization on the platelet outer cell membrane, and thrombin generation. Eventually, this increased thrombin-induced clot formation and retraction. Both Niclosamide and Clofazimine blocked this Spike-induced procoagulant response. These findings provide a pathogenic mechanism to explain lung thrombosis-associated with severe COVID-19 infection. We propose that Spike, present in SARS-CoV-2 virions or exposed on the surface of infected cells in the lungs, enhances the effects of inflammation and leads to local platelet stimulation and subsequent activation of the coagulation cascade. As platelet TMEM16F is central in this process, these findings reinforce the rationale of repurposing Niclosamide for COVID-19 therapy.

8.
Transfus Apher Sci ; 59(4): 102817, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32532691

RESUMEN

Passive immunotherapy with plasma derived from patients convalescent from SARS-CoV-2 infection can be a promising approach in the treatment of COVID-19 patients. It is important that Blood Establishments are prepared to satisfy requests for immune plasma by defining the requirements applicable to plasma donors and the standards for preparation, qualification, storage, distribution and control of use of the product. This position paper is aimed to give recommendations on biological characteristics of a plasma preparation from convalescent donors and to support the evaluation of this therapeutic approach in more rigorous investigations.


Asunto(s)
Betacoronavirus/inmunología , Infecciones por Coronavirus/terapia , Inmunización Pasiva , Neumonía Viral/terapia , Anticuerpos Antivirales/sangre , Eliminación de Componentes Sanguíneos/métodos , Donantes de Sangre , COVID-19 , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/inmunología , Selección de Donante/normas , Humanos , Sueros Inmunes/efectos adversos , Sueros Inmunes/aislamiento & purificación , Inmunización Pasiva/efectos adversos , Inmunización Pasiva/métodos , Pandemias , Neumonía Viral/sangre , Neumonía Viral/inmunología , Etiquetado de Productos , Riesgo , SARS-CoV-2 , Sueroterapia para COVID-19
9.
Blood Transfus ; 18(3): 163-166, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32453687

RESUMEN

Passive immunotherapy with plasma derived from convalescent patients recovering from SARS-CoV-2 infection can be a promising approach in the treatment of COVID-19 patients. It is important that blood establishments are ready to satisfy requests for immune plasma by defining the requirements applicable to plasma donors and the standards for preparation, qualification, storage, distribution, and control of product use. This Position paper aims to give recommendations on the biological characteristics of a plasma preparation from convalescent donors and to support the evaluation of this therapeutic approach in more rigorous investigations.


Asunto(s)
Anticuerpos Antivirales/uso terapéutico , Betacoronavirus/inmunología , Infecciones por Coronavirus/terapia , Inmunización Pasiva/métodos , Plasma/inmunología , Neumonía Viral/terapia , Anticuerpos Antivirales/efectos adversos , Bancos de Sangre/organización & administración , Bancos de Sangre/normas , Donantes de Sangre/legislación & jurisprudencia , COVID-19 , Europa (Continente) , Humanos , Esquemas de Inmunización , Inmunización Pasiva/efectos adversos , Inmunización Pasiva/normas , Consentimiento Informado , Italia , Pandemias , SARS-CoV-2 , Sueroterapia para COVID-19
10.
Nano Lett ; 20(5): 3663-3672, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32320257

RESUMEN

Most of existing solar thermal technologies require highly concentrated solar power to operate in the temperature range 300-600 °C. Here, thin films of refractory plasmonic TiN cylindrical nanocavities manufactured via flexible and scalable process are presented. The fabricated TiN films show polarization-insensitive 95% broadband absorption in the visible and near-infrared spectral ranges and act as plasmonic "nanofurnaces" capable of reaching temperatures above 600 °C under moderately concentrated solar irradiation (∼20 Suns). The demonstrated structures can be used to control nanometer-scale chemistry with zeptoliter (10-21 L) volumetric precision, catalyzing C-C bond formation and melting inorganic deposits. Also shown is the possibility to perform solar thermal CO oxidation at rates of 16 mol h-1 m-2 and with a solar-to-heat thermoplasmonic efficiency of 63%. Access to scalable, cost-effective refractory plasmonic nanofurnaces opens the way to the development of modular solar thermal devices for sustainable catalytic processes.

13.
ACS Appl Energy Mater ; 3(5): 4658-4668, 2020 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-33829149

RESUMEN

Electrocatalytic reduction of CO2 recently emerged as a viable solution in view of changing the common belief and considering carbon dioxide as a valuable reactant instead of a waste product. In this view, we herein propose the one-step synthesis of gold nanostructures of different morphologies grown on fluorine-doped tin oxide electrodes by means of pulsed-laser deposition. The resulting cathodes are able to produce syngas mixtures of different compositions at overpotentials as low as 0.31 V in CO2-presaturated aqueous media. Insights into the correlation between the structural features/morphology of the cathodes and their catalytic activity are also provided, confirming recent reports on the remarkable sensitivity toward CO production for gold electrodes exposing undercoordinated sites and facets.

14.
G Ital Cardiol (Rome) ; 20(12): 706-721, 2019 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-31834295

RESUMEN

The management of patients with heart disease or suspected heart disease, who are hospitalized and/or who should undergo surgery or an invasive procedure, is very complex for the comorbidities often present, the multiple therapies taken and the frequent presence of advanced cardiac devices.The purpose of this document is to provide indications and standardize the behavior of different clinicians in the management of heart disease patients or those with suspected heart disease in order (i) to manage acute cardiac conditions with appropriate timing and accuracy, and (ii) to define the cardiovascular risk in the individual patient with appropriate timing and indications, allowing patients to face any surgery or invasive procedure with the lowest risk correlated to his heart disease.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/métodos , Cardiopatías/cirugía , Atención Perioperativa/métodos , Cardiología/métodos , Cardiopatías/fisiopatología , Humanos , Italia , Riesgo , Factores de Tiempo
15.
Adv Mater ; 31(31): e1805513, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30773753

RESUMEN

Photoelectrochemical (PEC) water splitting is a promising approach for producing hydrogen without greenhouse gas emissions. Despite decades of unceasing efforts, the efficiency of PEC devices based on earth-abundant semiconductors is still limited by their low light absorption, low charge mobility, high charge-carrier recombination, and reduced diffusion length. Plasmonics has recently emerged as an effective approach for overcoming these limitations, although a full understanding of the involved physical mechanisms remains elusive. Here, the reported plasmonic effects are outlined, such as resonant energy transfer, scattering, hot electron injection, guided modes, and photonic effects, as well as the less investigated catalytic and thermal effects used in PEC water splitting. In each section, the fundamentals are reviewed and the most representative examples are discussed, illustrating possible future developments for achieving improved efficiency of plasmonic photoelectrodes.

16.
Oncotarget ; 10(3): 383-394, 2019 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-30719231

RESUMEN

Late diagnosis for Hepatocellular Carcinoma (HCC) remains one of the leading causes for the high mortality rate. The apurinic/apyrimidinic endonuclease 1 (APE1), an essential member of the base excision DNA repair (BER) pathway, contributes to cell response to oxidative stress and has other non-repair activities. In this study, we evaluate the role of serum APE1 (sAPE1) as a new diagnostic biomarker and we investigate the biological role for extracellular APE1 in HCC. sAPE1 level was quantified in 99 HCC patients, 50 non-HCC cirrhotic and 100 healthy controls. The expression level was significantly high in HCC (75.8 [67.3-87.9] pg/mL) compared to cirrhosis (29.8 [18.3-36.5] pg/mL] and controls (10.8 [7.5-13.2] pg/mL) (p < 0.001). The sAPE1 level corresponded with its protein expression in HCC tissue. sAPE1 had high diagnostic accuracy to differentiate HCC from cirrhotic (AUC = 0.87, sensitivity 88%, specificity 71%, cut-off of 36.3 pg/mL) and healthy subjects (AUC 0.98, sensibility 98% and specificity 83%, cut-off of 19.0 pg/mL). Recombinant APE1, exogenously added to JHH6 cells, significantly promotes IL-6 and IL-8 expression, suggesting a role of sAPE1 as a paracrine pro-inflammatory molecule, which may modulate the inflammatory status in cancer microenvironment. We described herein, for the first time to our knowledge, that sAPE1 might be considered as a promising diagnostic biomarker for HCC.

17.
Recenti Prog Med ; 109(2): 124-126, 2018 Feb.
Artículo en Italiano | MEDLINE | ID: mdl-29493637

RESUMEN

HLA typing requests for association studies of immune-mediated diseases are often redundant and inadequate. We designed a series of meta-analyses to evaluate the accuracy of typing and distribution of HLA alleles predisposing to diseases, aiming at developing an app that can help doctors in choosing the most suitable molecular analysis. The first study was on celiac disease (CD) and HLA-DQ in children. We searched all english articles published in the main bibliographic databases up to May 2016. The search strategy has been developed using controlled terms (e.g. MeSH) and free terms. We identified 1885 articles. 1334 abstracts were examined. 46 manuscripts were evaluated, and 13 studies were included in the meta-analysis (740 CD and 943 controls). The risk of developing CD in children with allelic variants encoding the HLA-DQ2.5 and/or HLA-DQ8 molecules has been confirmed. The greatest CD risk resides in carriers of two DQ2.5 molecules, i.e. subjects homozygous for the DQB1*02:01 and DQA1*05 alleles (OR=5.4, 95 % CI=4.1-6.8) compared to any other DQ genotype. Carriers of two DQB1*02:01 (chain ß2) alleles and one DQA1*05 (chain α5) allele have the same risk (p=0.8089) of DQ2.5 homozygotes (OR=5.3%, 95 CI=4,1 to 6.5). We found no differences between DQ8/ß2 and DQ2.5/DQ8, nor between ß2/DQX and DQ2.5/X. We suggest a two-step process: first typing the DQB1*02:01 allele and, in case of a negative result, full typing of HLA-DQ.


Asunto(s)
Enfermedad Celíaca/genética , Predisposición Genética a la Enfermedad , Antígenos HLA-DQ/genética , Alelos , Estudios de Casos y Controles , Enfermedad Celíaca/diagnóstico , Niño , Genotipo , Humanos , Aplicaciones Móviles
18.
Autoimmun Rev ; 16(12): 1230-1236, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29037901

RESUMEN

Juvenile Idiopathic Arthritis (JIA) is characterized with a variable pattern of articular involvement and systemic symptoms and, thus, it has been classified in several subtypes. Genetic predisposition to JIA is mainly due to HLA class II molecules (HLA-DRB1, HLA-DPB1), although HLA class I molecules and non-HLA genes have been implicated, too. Here, we carried out a meta-analysis including selected studies designed to assess HLA genetic background of JIA patients, compared to healthy controls; particularly, we focused our attention on HLA-DRB1. In summary, our meta-analysis showed four main findings regarding HLA-DRB1 locus as a genetic factor of JIA: i) HLA-DRB1*08 is a strong factor predisposing to JIA, both for oligo-articular and poly-articular forms (oJIA>pJIA); ii) HLA-DRB1*01 and HLA-DRB1*04 may be involved in the genetic predisposition of Rheumatoid Factor (RF) positive forms of JIA; iii) HLA-DRB1*11 was confirmed to be predisposing to oligo-articular JIA; iv) HLA-DRB1*04 was confirmed to have a role in systemic JIA. Importantly, RF positivity seems to select the JIA clinical subset with the strongest immunogenetic similarities with adult rheumatoid arthritis.


Asunto(s)
Artritis Juvenil/genética , Predisposición Genética a la Enfermedad , Cadenas HLA-DRB1/genética , Alelos , Artritis Juvenil/diagnóstico , Humanos , Factor Reumatoide
19.
Acta Cardiol ; 70(6): 707-11, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26717220

RESUMEN

OBJECTIVES: The objective of this study is to evaluate the prevalence of HR2 polymorphism among patients with pulmonary embolism (PE) and healthy subjects. BACKGROUND: Polymorphism in the factor V gene named HR2 has been described as a possible risk factor for venous thromboembolism (VTE) development. Contradictive results on this association have been reported. METHODS: Eighty-five patients admitted for PE and 72 healthy subjects were included in the study. Thrombophilia screening using genetic tests for factor V Leiden (G1691A/Leiden and HR2 haplotype) and other genetic mutations were investigated. RESULTS: Of 85 patients with PE, 20 (23.53%) carried the HR2 haplotype. Further, a majority of the patients with HR2 haplotype had recurrent venous thrombosis or PE (15 out of 20 patients). The HR2 haplotype was detected in 6 (8.3%) out of 72 healthy subjects. Patients had significantly higher HR2 haplotype frequency than healthy controls (P = 0.001). HR2 carriers had a three-fold increase in risk of developing PE (OR = 3.38, 95% CI = 1.27-8.96, P = 0.011). After adjustment for other tested defects for thrombophilia, HR2 haplotype was associated with increased risk of thromboembolic events (OR = 3.05, 95% CI = 1.11-8.35, P = 0.03). However, after adjustment for sex and age, HR2 polymorphism was no longer associated with the risk of thromboembolic event (OR = 1.22, 95% CI = 0.34-4.38, P = 0.76). CONCLUSIONS: Our study does not support the notion that factor V HR2 haplotype might be a risk factor for thrombosis despite its high prevalence among patients with PE.


Asunto(s)
ADN/genética , Factor V/genética , Predisposición Genética a la Enfermedad , Polimorfismo Genético , Embolia Pulmonar/genética , Adulto , Factor V/metabolismo , Femenino , Frecuencia de los Genes , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Embolia Pulmonar/sangre , Estudios Retrospectivos
20.
Sci Rep ; 5: 17989, 2015 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-26656852

RESUMEN

Brain-Derived Neurotrophic Factor (BDNF) has attracted increasing interest as potential biomarker to support the diagnosis or monitor the efficacy of therapies in brain disorders. Circulating BDNF can be measured in serum, plasma or whole blood. However, the use of BDNF as biomarker is limited by the poor reproducibility of results, likely due to the variety of methods used for sample collection and BDNF analysis. To overcome these limitations, using sera from 40 healthy adults, we compared the performance of five ELISA kits (Aviscera-Bioscience, Biosensis, Millipore-ChemiKine(TM), Promega-Emax(®), R&D-System-Quantikine(®)) and one multiplexing assay (Millipore-Milliplex(®)). All kits showed 100% sample recovery and comparable range. However, they exhibited very different inter-assay variations from 5% to 20%. Inter-assay variations were higher than those declared by the manufacturers with only one exception which also had the best overall performance. Dot-blot analysis revealed that two kits selectively recognize mature BDNF, while the others reacted with both pro-BDNF and mature BDNF. In conclusion, we identified two assays to obtain reliable measurements of human serum BDNF, suitable for future clinical applications.


Asunto(s)
Biomarcadores , Factor Neurotrófico Derivado del Encéfalo/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Ensayo de Inmunoadsorción Enzimática/normas , Adulto , Anciano , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Juego de Reactivos para Diagnóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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