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1.
Front Vet Sci ; 11: 1401592, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38933703

RESUMO

Feline chronic enteropathies (FCE) are common causes of chronic gastrointestinal signs in cats and include different diseases such as food-responsive enteropathy (FRE), inflammatory bowel diseases (IBD), and low-grade intestinal T-cell lymphoma (LGITL). Although changes in intestinal microbiota and fecal metabolites have been reported in dogs and humans with chronic enteropathy, research in cats has been limited. Therefore, this study aimed to evaluate the fecal microbiota and lipid-related fecal metabolites in cats with FCE to a clinically healthy comparison group (CG). A total of 34 cats with FCE (13 FRE, 15 IBD, and 6 LGITL) and 27 cats in the CG were enrolled in this study. The fecal microbiota was evaluated by the qPCR-based feline Dysbiosis Index (DI). The feline DI in cats with CE (median: 1.3, range: -2.4 to 3.8) was significantly higher (p < 0.0001) compared to CG (median: - 2.3, Range: -4.3 to 2.3), with no difference found among the FCE subgroups. The fecal abundances of Faecalibacterium (p < 0.0001), Bacteroides (p < 0.0001), Fusobacterium (p = 0.0398), Bifidobacterium (p = 0.0004), and total bacteria (p = 0.0337) significantly decreased in cats with FCE. Twenty-seven targeted metabolites were measured by gas chromatography-mass spectrometry, including long-chain fatty acids (LCFAs), sterols, and bile acids (BAs). Fecal concentrations of 5 of 12 LCFAs were significantly increased in cats with FCE compared to CG. Fecal concentrations of zoosterol (p = 0.0109), such as cholesterol (p < 0.001) were also significantly increased in cats with FCE, but those of phytosterols were significantly decreased in this group. No differences in fecal BAs were found between the groups. Although no differences were found between the four groups, the fecal metabolomic pattern of cats with FRE was more similar to that of the CG than to those with IBD or LGITL. This could be explained by the mild changes associated with FRE compared to IBD and LGITL. The study showed changes in intestinal microbiota and alteration of fecal metabolites in FCE cats compared to the CG. Changes in fecal lipids metabolites suggest a dysmetabolism of lipids, including LCFAs, sterols, and unconjugated BAs in cats with CE.

2.
ACS Appl Nano Mater ; 6(23): 21579-21586, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38093804

RESUMO

The strategic field of renewable energy production and storage requires novel nanoscale platforms that can feature competitive solar energy conversion properties. Photochemical reactions that promote energy storage, such as water splitting and oxygen-hydrogen evolution reactions, play a crucial role in this context. Here, we demonstrate a novel photoelectrochemical device based on large-area (cm2) self-organized Au nanowire (NW) arrays, uniformly coated with ultrathin TiO2 films. The NW arrays act both as transparent nanoelectrodes and as a plasmonic metasurface that resonantly enhances the very weak visible photocurrent generated by a prototype photoelectrochemical oxygen evolution reaction. We demonstrate a polarization-sensitive plasmon-enhanced photocurrent that reaches a gain of about 3.8 in the visible spectral range. This highlights the potential of our novel nanopatterned plasmonic platform in photochemistry and energy storage.

3.
Aquat Toxicol ; 265: 106779, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38016241

RESUMO

Pharmaceuticals released into the environment (PiEs) represent an environmental problem of growing concern for the health of ecosystems and humans. An increasing number of studies show that PiEs pose a risk to aquatic organisms. The aim of the present work was to contribute to increasing the knowledge of the effects of PiE on marine biota focusing on the effect of paracetamol on the motility of hemocytes in Mytilus galloprovincialis, a bivalve mollusk species widely utilized as bioindicator organism. Hemocytes are the immunocompetent cells of bivalve mollusks. An early and key stage of mollusk immune response is represented by the recruitment and migration of these cells to the site of infection. Therefore, motility is an intrinsic characteristic of these cells. Here, we first characterized the spontaneous cell movement of M. galloprovincialis hemocytes when plated in a TC-treated polystyrene 96-well microplate. Two different cellular morphotypes were distinguished based on their appearance and motility behavior: spread cells and round-star-shaped cells. The two motility morphotypes were characterized by different velocities as well as movement directness, which were significantly lower in round-star-shaped cells with respect to spread cells. The sensitivity of the motility of M. galloprovincialis hemocytes to paracetamol at different concentrations (0.02, 0.2 and 2 mg/L) was investigated in vitro after 1h and 24h exposure. Paracetamol induced alterations in the motility behavior (both velocity and trajectories) of the hemocytes and the effects were cell-type specific. The study of hemocyte movements at the single cell level by cell tracking and velocimetric parameters analysis provides new sensitive tools for assessing the effects of emerging pollutants at the cellular levels in non-target organisms.


Assuntos
Mytilus , Poluentes Químicos da Água , Animais , Humanos , Lisossomos , Hemócitos , Acetaminofen/toxicidade , Ecossistema , Poluentes Químicos da Água/toxicidade
4.
ACS Appl Nano Mater ; 6(19): 18623-18631, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37854851

RESUMO

Thermal scanning-probe lithography (t-SPL) is a high-resolution nanolithography technique that enables the nanopatterning of thermosensitive materials by means of a heated silicon tip. It does not require alignment markers and gives the possibility to assess the morphology of the sample in a noninvasive way before, during, and after the patterning. In order to exploit t-SPL at its peak performances, the writing process requires applying an electric bias between the scanning hot tip and the sample, thereby restricting its application to conductive, optically opaque, substrates. In this work, we show a t-SPL-based method, enabling the noninvasive high-resolution nanolithography of photonic nanostructures onto optically transparent substrates across a broad-band visible and near-infrared spectral range. This was possible by intercalating an ultrathin transparent conductive oxide film between the dielectric substrate and the sacrificial patterning layer. This way, nanolithography performances comparable with those typically observed on conventional semiconductor substrates are achieved without significant changes of the optical response of the final sample. We validated this innovative nanolithography approach by engineering periodic arrays of plasmonic nanoantennas and showing the capability to tune their plasmonic response over a broad-band visible and near-infrared spectral range. The optical properties of the obtained systems make them promising candidates for the fabrication of hybrid plasmonic metasurfaces supported onto fragile low-dimensional materials, thus enabling a variety of applications in nanophotonics, sensing, and thermoplasmonics.

5.
Int J Biol Macromol ; 253(Pt 6): 127406, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37832612

RESUMO

This work proposes the use of supercritical CO2 to impregnate starch (potato and corn) aerogels with quercetin for a potential fungistatic application. Starch aerogels were successfully produced with supercritical drying, but different results were found depending on the amylose/amylopectin ratio. A higher amount of amylose increases aerogels' specific surface area (with a structure with nanofibrils and nodes) due to the linear and amorphous character of this polymer, whereas a higher amount of amylopectin decreases this property until values of only 25 m2·g-1, obtaining an aerogel with a rough surface. These results were explained with XRD, thermogravimetric, and rheological results (triple step with two temperature sweeps and a time sweep and steady state analysis) concerning hydrogel formation. In fact, retrogradation step plays a more important role in hydrogel formation for a starch source with a higher amount of amylopectin due to an increase in the different polymers' interactions. Supercritical impregnation of quercetin on the aerogels was successfully performed (a loading around 0.30 % with respect to the amount of polymer), and in vitro results indicated that the aerogels produced a fungistatic effect on different types of fungi, but only in the first 12 h because the microorganisms adapted to the surrounding environment. Finally, a compartmental model was used to fit the drug release, which is controlled by quercetin aqueous solubility, indicating the main mass transfer resistances (mass transfer through aerogels was always around 500 min-1 and dissolution process mass transfer from 5·10-3 to 1.65·10-3 s-1) and how an increase in the specific surface area of the aerogels (in the case of corn aerogel) provided a stronger initial burst (70-80 % in 20 min). In fact, this initial burst release was mathematically related to a parameter, that varies from 0.178 to 0.036 depending on the aerogel composition. This study shows that starch aerogels can be impregnated with a hydrophobic compound with fungistatic effect by using supercritical CO2, modifying in addition the drug release by changing the native starch.


Assuntos
Portadores de Fármacos , Amido , Amido/química , Portadores de Fármacos/química , Amilose , Quercetina , Amilopectina , Modelos Epidemiológicos , Dióxido de Carbono , Hidrogéis
6.
Plants (Basel) ; 12(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37514243

RESUMO

The success of Space missions and the efficacy of colonizing extraterrestrial environments depends on ensuring adequate nutrition for astronauts and autonomy from terrestrial resources. A balanced diet incorporating premium quality fresh foods, such as microgreens, is essential to the mental and physical well-being of mission crews. To improve the nutritional intake of astronaut meals, two levels of potassium iodide (KI; 4 µM and 8 µM) and an untreated control were assessed for iodine (I) biofortification, and overall nutraceutical profile of four microgreens: tatsoi (Brassica rapa L. subsp. narinosa), coriander (Coriandrum sativum L.), green basil, and purple basil (Ocimum basilicum L.). A dose-dependent increase in I was observed at 8 µM for all species, reaching concentrations of 200.73, 118.17, 93.97, and 82.70 mg kg-1 of dry weight, in tatsoi, coriander, purple basil, and green basil, respectively. Across species, I biofortification slightly reduced fresh yield (-7.98%) while increasing the antioxidant activity (ABTS, FRAP, and DPPH). LC-MS/MS Q extractive orbitrap analysis detected 10 phenolic acids and 23 flavonoids among microgreen species. The total concentration of phenolic acids increased (+28.5%) in purple basil at 8 µM KI, while total flavonoids in coriander increased by 23.22% and 34.46% in response to 4 and 8 µM KI, respectively. Both doses of KI increased the concentration of total polyphenols in all species by an average of 17.45%, compared to the control.

7.
Molecules ; 28(12)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37375237

RESUMO

Polyphenols have attracted great interest as potent antioxidant compounds and nutraceuticals; however, their antioxidant properties represent a multifaceted phenomenon, including pro-oxidant effects under particular conditions and complex behavior when multiple polyphenols are simultaneously present. Moreover, their intracellular behavior cannot always be predicted from their ability to counteract the production of ROS in acellular assays. The present work aimed to study the direct intracellular redox activity of two polyphenols, resveratrol and quercetin, singly and in mixture in a cellular short-term bioassay under both basal and pro-oxidant conditions. The study was carried out by spectrofluorimetric assessment of the intracellular fluorescence of CM-H2DCFDA-charged HeLa cells under either basal conditions, due to the reactive species associated with the normal cellular oxidative metabolism, or pro-oxidant conditions induced by H2O2 exposure. Under basal conditions, the obtained results showed a significant antioxidant effect of quercetin and a weaker antioxidant effect of resveratrol when used singly, while antagonism of their effect was detected in their equimolar mixtures at all the concentrations used. Under exposure of the cells to H2O2, quercetin exhibited a dose-dependent intracellular antioxidant activity whereas resveratrol manifested a pro-oxidant intracellular activity, while their equimolar mixtures showed an intracellular interaction between the 2 polyphenols, with additive effects at 5 µM and synergic at 25 µM and 50 µM. Thus, the results clarified the direct intracellular antioxidant/pro-oxidant activity of quercetin and resveratrol alone and in their equimolar mixtures in the cell model HeLa cells and highlighted that the antioxidant properties of polyphenols in mixtures at the cellular level depend not only on the nature of the compounds themselves but also on the type of interactions in the cellular system, which in turn are influenced by the concentration and the oxidative status of the cell.


Assuntos
Quercetina , Estilbenos , Humanos , Resveratrol/farmacologia , Quercetina/farmacologia , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peróxido de Hidrogênio , Células HeLa , Polifenóis/farmacologia , Oxirredução , Estilbenos/farmacologia
8.
Plants (Basel) ; 12(12)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37375931

RESUMO

With increasing frequency and severity of droughts in various parts of the world, agricultural productivity may suffer major setbacks. Among all the abiotic factors, drought is likely to have one of the most detrimental effects on soil organisms and plants. Drought is a major problem for crops because it limits the availability of water, and consequently nutrients which are crucial for plant growth and survival. This results in reduced crop yields, stunted growth, and even plant death, according to the severity and duration of the drought, the plant's developmental stage, and the plant's genetic background. The ability to withstand drought is a highly complex characteristic that is controlled by multiple genes, making it one of the most challenging attributes to study, classify, and improve. Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR) technology has opened a new frontier in crop enhancement, revolutionizing plant molecular breeding. The current review provides a general understanding of principles as well as optimization of CRISPR system, and presents applications on genetic enhancement of crops, specifically in terms of drought resistance and yield. Moreover, we discuss how innovative genome editing techniques can aid in the identification and modification of genes conferring drought tolerance.

9.
Nanotechnology ; 34(36)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37279698

RESUMO

Following defocused ion beam sputtering, large area highly corrugated and faceted nanoripples are formed on calcite (10.4) faces in a self-organized fashion. High resolution atomic force microscopy (AFM) imaging reveals that calcite ripples are defined by facets with highly kinked (11.0) and (21¯.12) terminations.In situAFM imaging during the exposure of such modified calcite surfaces to PbCl2aqueous solution reveals that the nanostructured calcite surface promotes the uptake of Pb. In addition, we observed the progressive smoothing of the highly reactive calcite facet terminations and the formation of Pb-bearing precipitates elongated in registry with the underlying nanopattern. By SEM-EDS analysis we quantified a remarkable 500% increase of the Pb uptake rate, up to 0.5 atomic weight % per hour, on the nanorippled calcite in comparison to its freshly cleaved (10.4) surfaces. These results suggest that nanostructurated calcite surfaces can be used for developing future systems for lead sequestration from polluted waters.


Assuntos
Carbonato de Cálcio , Nanoestruturas , Chumbo , Água , Microscopia de Força Atômica/métodos
10.
ACS Appl Nano Mater ; 6(7): 6230-6240, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37092122

RESUMO

Thin-film organic photovoltaic (OPV) devices represent an attractive alternative to conventional silicon solar cells due to their lightweight, flexibility, and low cost. However, the relatively low optical absorption of the OPV active layers still represents an open issue in view of efficient devices that cannot be addressed by adopting conventional light coupling strategies derived from thick PV absorbers. The light coupling to thin-film solar cells can be boosted by nanostructuring the device interfaces at the subwavelength scale. Here, we demonstrate broadband and omnidirectional photon harvesting in thin-film OPV devices enabled by highly ordered one-dimensional (1D) arrays of nanogrooves. Laser interference lithography, in combination with reactive ion etching (RIE), provides the controlled tailoring of the height and periodicity of the silica grooves, enabling effective tuning of the anti-reflection properties in the active organic layer (PTB7:PCBM). With this strategy, we demonstrate a strong enhancement of the optical absorption, as high as 19% with respect to a flat device, over a broadband visible and near-infrared spectrum. The OPV device supported on these optimized nanogrooved substrates yields a 14% increase in short-circuit current over the corresponding flat device, highlighting the potential of this large-scale light-harvesting strategy in the broader context of thin-film technologies.

11.
Mar Environ Res ; 188: 105988, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37080092

RESUMO

The work aimed to study the induction of morphological alterations in M. galloprovincialis in the field and its suitability to be integrated into a sensitive, simple, and cost-effective cell-based multimarker approach for the detection of the stress status induced by pollution in coastal marine environments in view of ecotoxicological biomonitoring and assessment application. Cellular morphometric alterations was paralleled by the analysis of standardized biomarkers such as lysosomal membrane destabilization, and genotoxocity biomarkers such as micronuclei and binuclated cells frequencies were investigated. The study was carried out by means of a transplanting experiment in the field, using caged organisms from an initial population exposed in the field in two multi-impacted coastal sites of the central Mediterranean area, Bagnoli in the eastern Tyrrhenian Sea and Augusta-Melilli-Priolo in the western Ionian Sea. Capo Miseno (NA) for the Tyrrhenian area and Brucoli (ME) for the Ionian area were chosen as control sites. Hemocyte enlargement and filopodial elongation increased frequencies were observed in organisms exposed to the impacted sites. These morphometric alterations showed strong agreement with the lysosomal membrane destabilization and biomarkers of genotoxicity, suggesting their usefulness in detecting the pollutant-induced stress syndrome related to genotoxic damage.


Assuntos
Mytilus , Poluentes Químicos da Água , Animais , Hemócitos , Monitoramento Ambiental , Poluição Ambiental , Biomarcadores/análise , Poluentes Químicos da Água/análise
12.
Nanoscale ; 15(4): 1953-1961, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36625311

RESUMO

Novel light harvesting platforms and strategies are crucial to develop renewable photon to energy conversion technologies that overcome the current global energy and environmental challenges. Two-dimensional (2D) transition metal dichalcogenide (TMD) semiconductor layers are particularly attractive for photoconversion applications but new ultra-compact photon harvesting schemes are urgently required to mitigate their poor photon absorption properties. Here, we propose a flat-optics scheme based on nanogrooved ultra-thin MoS2 layers conformally grown onto large area (cm2 scale) nanopatterned templates. The subwavelength re-shaping of the 2D-TMD layers promotes the excitation of photonic Rayleigh anomaly (RA) modes, uniquely boosting a strong in-plane electromagnetic confinement. By tailoring the illumination conditions, we demonstrate effective tuning of the photonic anomalies over a broadband visible spectrum across the absorption band of relevant polluting dye molecules. Thanks to the strong photonic in-plane confinement, we achieve a resonant enhancement of the photodissociation rate of methylene blue (MB) molecules, well above a factor of 2. These results highlight the potential of flat-optics photon harvesting schemes for boosting photoconversion efficiency in large-scale hybrid 2D-TMD/polymer layers, with a strong impact in various applications ranging from new-generation photonics to waste water remediation and renewable energy storage.

13.
Toxics ; 11(1)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36668785

RESUMO

Throughout the cold and the warm periods of 2020, chemical and toxicological characterization of the water-soluble fraction of size segregated particulate matter (PM) (<0.49, 0.49−0.95, 0.95−1.5, 1.5−3.0, 3.0−7.2 and >7.2 µm) was conducted in the urban agglomeration of Thessaloniki, northern Greece. Chemical analysis of the water-soluble PM fraction included water-soluble organic carbon (WSOC), humic-like substances (HULIS), and trace elements (V, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd and Pb). The bulk (sum of all size fractions) concentrations of HULIS were 2.5 ± 0.5 and 1.2 ± 0.3 µg m−3, for the cold and warm sampling periods, respectively with highest values in the <0.49 µm particle size fraction. The total HULIS-C/WSOC ratio ranged from 17 to 26% for all sampling periods, confirming that HULIS are a significant part of WSOC. The most abundant water-soluble metals were Fe, Zn, Cu, and Mn. The oxidative PM activity was measured abiotically using the dithiothreitol (DTT) assay. In vitro cytotoxic responses were investigated using mitochondrial dehydrogenase (MTT). A significant positive correlation was found between OPmDTT, WSOC, HULIS and the MTT cytotoxicity of PM. Multiple Linear Regression (MLR) showed a good relationship between OPMDTT, HULIS and Cu.

14.
J Hazard Mater ; 448: 130872, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36716558

RESUMO

Atmospheric particulate matter (PM) is one of the major risks for global health. The exact mechanisms of toxicity are still not completely understood leading to contrasting results when different toxicity metrics are compared. In this work, PM10 was collected at three sites for the determination of acellular oxidative potential (OP), intracellular oxidative stress (OSGC), cytotoxicity (MTT assay), and genotoxicity (Comet assay). The in vitro tests were done on the A549 cell line. The objective was to investigate the correlations among acellular and intracellular toxicity indicators, the variability among the sites, and how these correlations were influenced by the main sources by using PMF receptor model coupled with MLR. The OPDTTV, OSGCV, and cytotoxicity were strongly influenced by combustion sources. Advection of African dust led to lower-than-average intrinsic toxicity indicators. OPDTTV and OSGCV showed site-dependent correlations suggesting that acellular OP may not be fully representative of the intracellular oxidative stress at all sites and conditions. Cytotoxicity correlated with both OPDTTV and OSGCV at two sites out of three and the strength of the correlation was larger with OSGCV. Genotoxicity was correlated with cytotoxicity at all sites and correlated with both, OPDTTV and OSGCV, at two sites out of three. Results suggest that several toxicity indicators are useful to gain a global picture of the potential health effects of PM.


Assuntos
Poluentes Atmosféricos , Material Particulado , Material Particulado/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Poeira , Estresse Oxidativo
15.
Plants (Basel) ; 11(22)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36432786

RESUMO

Microgreens represent a new generation of food products, commonly used to garnish and embellish culinary dishes, and recently associated with an increasing interest in their nutraceutical and phytochemical profiles. Four Apiaceae species: Pimpinella anisum L. (anise), Anthriscus cerefolium L. (chervil), Carum carvi L. (caraway), and Anethum graveolens L. (dill) were assessed for fresh yield, macro- and microminerals, total chlorophylls, total ascorbic acid, carotenoids, polyphenols, and their antioxidant activity. Anise was the species yielding the most (2.53 kg m-2) and having the highest lutein content (18.4 µg g-1 dry weight (DW)). Chervil and dill were characterized by the highest total ascorbic acid content (~151 mg AA g-1 fresh weight (FW)). The phenolic profile highlighted the presence of five flavonoid derivatives and 12 phenolic acid derivatives, with quinic acid derivatives being the most abundant phenols in the species tested. In addition, anise, caraway, and dill proved to be considerably rich in total polyphenols (~11056 µg g-1 DW). Caraway and dill were characterized by the highest antioxidant activity measured by the DPPH and ABTS methods, whereas the FRAP method revealed caraway as having the highest antioxidant activity. Such results highlight the potential of Apiaceae species as an alternative to other families which are commonly used for microgreens production.

16.
Opt Express ; 30(10): 17371-17382, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221562

RESUMO

Flat optics nanogratings supported on thin free-standing membranes offer the opportunity to combine narrowband waveguided modes and Rayleigh anomalies for sensitive and tunable biosensing. At the surface of high-refractive index Si3N4 membranes we engineered lithographic nanogratings based on plasmonic nanostripes, demonstrating the excitation of sharp waveguided modes and lattice resonances. We achieved fine tuning of these optical modes over a broadband Visible and Near-Infrared spectrum, in full agreement with numerical calculations. This possibility allowed us to select sharp waveguided modes supporting strong near-field amplification, extending for hundreds of nanometres out of the grating and enabling versatile biosensing applications. We demonstrate the potential of this flat-optics platform by devising a proof-of-concept nanofluidic refractive index sensor exploiting the long-range waveguided mode operating at the sub-picoliter scale. This free-standing device configuration, that could be further engineered at the nanoscale, highlights the strong potential of flat-optics nanoarrays in optofluidics and nanofluidic biosensing.


Assuntos
Técnicas Biossensoriais , Luz , Óptica e Fotônica , Refratometria
17.
Plants (Basel) ; 11(15)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35956509

RESUMO

A promising strategy for sustainably increasing the quality and yield of horticultural products is the use of natural plant biostimulants. In this work, through a greenhouse experiment, we evaluated the effect of a legume-derived biostimulant at three dose treatments (0.0 control, 2.5 mL L-1, and 5.0 mL L-1) on the yield performance, nutrients traits, leaf anatomical traits, gas exchanges, and carbon photosynthetic assimilation of greenhouse lettuce. The lettuce plants were foliar sprayed every 7 days for 5 weeks. The application of plant biostimulant, at both lower and higher dosages, increased the nutrient use efficiency, root dry weight, and leaf area. However, it is noteworthy that the 5.0 mL L-1 dose enhanced photosynthetic activity in the early phase of growth (15 DAT), thus supplying carbon skeletons useful for increasing the number of leaves and their efficiency (higher SPAD), and for boosting nutrient uptake (P, S, and K) and transport to leaves, while the 2.5 mL L-1 dose exerted specific effects on roots, increasing their dimension and enabling them to better use nitrate and Ca. A higher dose of biostimulant application might find its way in shorter growing cycle, thus presenting new horizons for new lines of research in baby leaves production.

18.
Anal Chim Acta ; 1206: 339556, 2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35473859

RESUMO

A gold nanostructured electrochemical sensor based on modified GC electrode for thiols' detection is described and characterized. This sensor is a suitable device for the measurement of the oxidative potential (OP) of the atmospheric particulate matter (PM), considered a global indicator of adverse health effects of PM, as an alternative to the classic spectrophotometric methods. The operating principle is the determination of the OP, through the measurement of the consumption of DTT content. The DTT-based chemical reactivity is indeed a quantitative acellular probe for assessment of the capacity of the atmospheric PM to catalyze reactive oxygen species generation which contributes to the induction of oxidative stress in living organisms and in turn to the outcome of adverse health effects. To make the sensors, glassy carbon electrodes, traditional (GC) and screen printed (SPE) electrodes, have been electrochemically modified with well-shaped rounded gold nanoparticles (AuNPs) by using a deposition method that allows obtaining a stable and efficient modified surface in a very simple and reproducible modality. The chemical and morphological characterization of the nano-hybrid material has been performed by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy coupled with electron dispersive spectroscopy analysis (SEM/EDS). The electrochemical properties have been evaluated by cyclic voltammetry (CV) and chrono-amperometry (CA) in phosphate buffer at neutral pH as requested in DTT assay for OP measurements. The electroanalytical performances of the sensor in DTT detection are strongly encouraging showing low LODs (0.750 µM and 1.5 µM), high sensitivity (0.0622 µA cm-2 µM-1 and 0.0281 µA cm-2 µM-1), wide linear and dynamic ranges extending over 2-4 orders of magnitude and high selectivity. FIA preliminary results obtained on measuring the DTT rate consumption in six PM aqueous extracts samples showed a good correlation with measurements obtained in parallel on the same set of samples by using the classic spectrophotometric method based on the Ellman's reactive use. These results confirm the high selectivity of the method and its suitability for application to be applied in PM oxidative potential measurements.


Assuntos
Ouro , Nanopartículas Metálicas , Carbono/química , Ditiotreitol , Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Nanopartículas Metálicas/química , Estresse Oxidativo , Fosfatos
19.
Nanotechnology ; 33(30)2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35385839

RESUMO

Highly porous Germanium surfaces with uniformly distributed columnar nanovoid structures are fabricated over a large area (wafer scale) by large fluence Sn+irradiation through a thin silicon nitride layer. The latter represents a one-step highly reproducible approach with no material loss to strongly increase photon harvesting into a semiconductor active layer by exploiting the moth-eye antireflection effect. The ion implantation through the nitride cap layer allows fabricating porous nanostructures with high aspect ratio, which can be tailored by varying ion fluence. By comparing the reflectivity of nanoporous Ge films with a flat reference we demonstrate a strong and omnidirectional reduction in the optical reflectivity by a factor of 96% in the selected spectral regions around 960 nm and by a factor of 67.1% averaged over the broad spectral range from 350 to 1800 nm. Such highly anti-reflective nanostructured Ge films prepared over large-areas with a self-organized maskless approach have the potential to impact real world applications aiming at energy harvesting.

20.
Animals (Basel) ; 13(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36611675

RESUMO

Feline calicivirus (FCV) infection in cats can led to several diverse clinical presentations, ranging from mild upper respiratory signs to virulent systemic disease. Herein, we report a paw and mouth disease case in a 7-year-old household cat due to an FCV infection. An asymptomatic cat living in the same household was also infected with FCV. Clinical and pathological investigations were combined with the molecular and phenotypical characterization of the FCV strains. The RNA of the FCV was detected using qualitative and quantitative reverse transcription (RT)-PCR assays, and FCV antigen was confirmed by immunohistochemistry. After the whole genome analysis, the strains detected in the two cats appeared to be genetically diverse from FCVs previously detected in association with paw and mouth disease and with virulent systemic disease. Interestingly, the isolates obtained in this study were resistant to low pH conditions and slightly susceptible to bile salts, but they were susceptible to a trypsin treatment, revealing a phenotype pattern that is different from that which has been observed for respiratory FCVs.

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