The airborne transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via respiratory fluids and droplets suggests that mouthwashes containing substances with virucidal activity ...can help reduce viral spread. We conducted a multicenter, double-blind, placebo-controlled, randomized trial to assess the virucidal activity of cetylpyridinium chloride (CPC) mouthwashes. Outpatients who tested positive for SARS-CoV-2 infection with or without symptoms were randomized to perform washes and gargles for 1 min with 15 mL of either colored distilled water or 0.07% CPC (Vitis CPC Protect) mouthwash. The study outcomes were the SARS-CoV-2 log10 viral RNA load and the nucleocapsid protein levels, both in saliva at 1 and 3 h after the intervention. In total, 118 patients were enrolled and randomized (mean SD, age 46 14 y). Thirteen of 118 participants (11%) did not complete follow-up or had insufficient sample volume for testing and were excluded from the analysis. The assessment of the viral load showed no significant differences between groups at any of the investigated points. However, the levels of SARS-CoV-2 nucleocapsid protein of lysed viruses were significantly higher in the CPC group compared with the control group at 1 h (adjusted difference 269.3 pg/mL; 95% confidence interval CI, 97.1–441.5) and at 3 h postintervention (561.1 pg/mL; 95% CI, 380.0–742.2). In nonhospitalized patients with asymptomatic or mild symptomatic SARS-CoV-2 infection, a 0.07% CPC mouthwash, compared to placebo, was associated with a significant increase of nucleocapsid protein levels in saliva, indicating enhanced disruption of viral particles.
This work describes the behaviour of water molecules in 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid under nanoconfinement, between graphene sheets. By means of molecular dynamics ...simulations, the adsorption of water molecules at the graphene surface is studied. A depletion of water molecules in the vicinity of the neutral and negatively charged graphene surfaces, and their adsorption at the positively charged surface are observed in line with the preferential hydration of the ionic liquid anions. The findings are appropriately described using a two-level statistical model. The confinement effect on the structure and dynamics of the mixtures is thoroughly analyzed using the density and the potential of mean force profiles, as well as by the vibrational densities of the states of water molecules near the graphene surface. The orientation of water molecules and the water-induced structural transitions in the layer closest to the graphene surface are also discussed.
ABSTRACT
We here report the detection of extended He ii λ4686 nebular emission in the central region of NGC 1569 using the integral field spectrograph MEGARA at the 10.4 m Gran Telescopio Canarias. ...The observations cover a field of view (FoV) of 12.5 arcsec × 11.3 arcsec at a seeing-limited spatial resolution of ∼15 pc and at a spectral resolution of R = 6000 in the wavelength range 4330–5200 Å. The emission extends over a semicircular arc of ∼40 pc width and ∼150 pc diameter around the superstar cluster A (SSC-A). The AV derived using Balmer decrement varies from the Galactic value of 1.6 mag to a maximum of ∼4.5 mag, with a mean value of 2.65 ± 0.60 mag. We infer 124 ± 11 Wolf–Rayet (WR) stars in SSC-A using the He ii λ4686 broad feature and AV = 2.3 mag. The He+ ionizing photon rate from these WR stars is sufficient to explain the luminosity of the He ii nebula. The observationally determined total He+ and H0 ionizing photon rates, their ratio, and the observed number of WR stars in SSC-A are all consistent with the predictions of simple stellar population models at an age of 4.0 ± 0.5 Myr and a mass of (5.5 ± 0.5) × 105 M⊙. Our observations reinforce the absence of WR stars in SSC-B, the second most massive cluster in the FoV. None of the other locations in our FoV where He ii λ4686 emission has been reported from narrow-band imaging observations contain WR stars.
Inhibition and paradoxical choice González, Valeria V.; Blaisdell, Aaron P.
Learning & behavior,
12/2023, Letnik:
51, Številka:
4
Journal Article
Recenzirano
Odprti dostop
The present study evaluated the role of inhibition in paradoxical choice in pigeons. In a paradoxical choice procedure, pigeons receive a choice between two alternatives. Choosing the “suboptimal” ...alternative is followed 20% of the time by one cue (the S+) that is always reinforced, and 80% of the time by another cue (S-) that is never reinforced. Thus, this alternative leads to an overall reinforcement rate of 20%. Choosing the “optimal” alternative, however, is followed by one of two cues (S3 or S4), each reinforced 50% of the time. Thus, this alternative leads to an overall reinforcement rate of 50%. González and Blaisdell (
2021
) reported that development of paradoxical choice was positively correlated to the development of inhibition to the S- (signal that no food will be delivered on that trial) post-choice stimulus. The current experiment tested the hypothesis that inhibition to a post-choice stimulus is causally related to suboptimal preference. Following acquisition of suboptimal preference, pigeons received two manipulations: in one condition one of the cues in the optimal alternative (S4) was extinguished and, in another condition, the S- cue was partially reinforced. When tested on the choice task afterward, both manipulations resulted in a decrement in suboptimal preference. This result is paradoxical given that both manipulations made the suboptimal alternative the richer option. We discuss the implications of our results, arguing that inhibition of a post-choice cue increases attraction to or value of that choice.
In this article, a mathematical microbial electrochemical cell (MEC) dynamic model is proposed. The model is derived from mass balances of a continuous flow MEC system which consists of two ...interconnected chambers. The system is described by a set of nonlinear ordinary differential equations (ODEs) that describes: (i) the competition of anodophilic and methanogenic microbial populations for a common substrate and; (ii) biomass growth and retention in the anodic compartment. Open loop behavior is evaluated via numerical simulations. The model is suitable both for process optimization and online control applications. Parametric sensitivity, stability, and convergence properties of the proposed model are also addressed in this article.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Pharmaceuticals and their by-products are recalcitrant contaminants in water. Moreover, the high consumption of these drugs has many detrimental effects on body waters and ecosystems. In this timely ...review, the advances in molecular engineering of layered double hydroxides (LDH) that have been used for the removal of pharmaceutical pollutants are discussed. The approach starts from the strategies to obtain homogeneous synthesis of LDH that allow the doping and/or surface functionalization of different metals and oxides, producing heterojunction systems as well as composites with carbon and silica-based materials with high surface area. Adsorption is considered as a traditional removal of pharmaceutical pollutants, so the kinetic and mechanism of this phenomenon are analyzed based on pH, temperature, ionic strength, in order to obtain new insights for the formation of multifunctional LDH. Advanced oxidation methodologies, mainly heterogeneous photocatalysis and Fenton-like processes, stand out as the more efficient even to obtain the mineralization of the drugs. The LDH have the advantage of structural memory that favors regeneration processes. The reconstruction of calcined LDH can be used to improve drug removal, through a combination of adsorption capacity/catalytic activity. A meticulous analysis of the persistence, toxicity and bioaccumulation of the most common pharmaceuticals has allowed us to highlight the ability of the LDH to remove recalcitrant drugs at relatively low concentrations (ppm, ppb), in contrast to other mixed oxide nanostructures and homogeneous oxidation processes. In this sense, the mechanism of drug removal by LDH is discussed based on the importance of the use of composites, scavenger agents, Fenton and electro-Fenton processes, membranes, thin films and coatings, among others. In addition, the ecotoxicity of LDH is also reviewed to indicate that these layered structures can exhibit biocompatibility or high toxicity depending on the adsorbed drug and ions/metals that compose them. Undoubtedly, the LDH have a unique flexible structure with adsorption capacity and catalytic activity, facts that explain the important reasons for their extensive use in the environmental remediation of pharmaceutical pollutants from water.
•LDH nanomaterials can resolve the actual emerging pharmaceutical pollutants issues.•The use of LDH positively affects the water cycle to overcome toxic waste.•LDH can work as an adsorbent/catalytic agent for removal of pharmaceuticals.•Reconstruction of calcined LDH can be used to improve drug removal.
Our main objective was to investigate the numbers of days necessary for the disappearance of the cough caused by an angiotensin‐converting enzyme inhibitor (ACEI) subsequent to the discontinuation of ...treatment, and to identify the associated factors that contribute to the appearance of said cough and angioneurotic edema. We studied 1101 patients with hypertension treated with an ACEI for 15 years. A multivariate analysis of binary logistic regression was performed to identify predisposing cough factors. In the 1101 patients treated with ACEI, 270 were diagnosed as having a cough caused by an ACEI (24.5%). The average numbers of days until the cough disappeared was 6.06 ± 1.58 days. The significant predisposing factors of the cough were female sex (odds ratio OR, 1.77; 95% confidence interval CI, 1.31‐2.39), previous diagnosis of obstructive sleep apnea (OR, 1.85; 95% CI, 1.31‐2.61), and concomitant use of thiazides (OR, 1.50; 95% CI, 1.11‐2.04). Statins were shown as a protective factor (OR, 0.69; 95% CI, 0.51‐0.93). In the case of angioneurotic edema, 25 patients (2.3%) were diagnosed, without significant determinants. Our analysis showed that the cough disappeared in a period of ≤10 days for 96.7% of patients diagnosed with a cough, subsequent to the discontinuation of ACEI treatment. The risk factors identified for the appearance of a cough include female sex, previous obstructive sleep apnea, and concomitant use of thiazides. The use of statins was found to be a protective factor. The incidence of angioneurotic edema in our cohort is greater than that described in the literature.
The aim of this study was to compare the pushout bond strength (POBS) of three hydraulic cements, when used at thicknesses of 3 and 5 mm.
78 root slices of 3 and 5 mm of thickness were obtained from ...human teeth. Cylindrical cavities of 1.4 mm of diameter were drilled and filled with Biodentine (BD), Totalfill Root Repair paste (TF) or ProRoot MTA White (PMTA). Pushout tests were performed 21 days later. The fracture pattern of each sample was also analyzed. POBS data were analyzed with Welch and Brown-Forsythe and Tamhane's post hoc tests and a Weibull analysis was also performed.
In the 3 mm group, TF showed significantly lower bond strength than BD and PMTA. In the 5 mm group, BD showed significantly higher bond strength than TF. Both BD and TF showed higher bond strength when the thickness of the sample increased, while PMTA did not.
TF and BD achieve higher pushout bond strength resistance when used at a thickness of 5 mm than at 3 mm, while the mean resistance of PMTA is less influenced by the thickness. At 5 mm of thickness, BD and PMTA exhibit similar resistance to displacement. However, the behavior of BD is more predictable than that of its predecessor. BD is a reliable hydraulic cement for clinical situations where thick cavities need to be filled and displacement resistance plays an important role. Clinicians need to consider choosing specific hydraulic cements according to the thickness of material to be used.
► The growth rate of four seawater microalgae strains is modeled. ► The influence of nitrate limitation on lipids productivity enhancement is modeled. ► Continuous operation is compared to two-stage ...culture to improve lipid accumulation. ► Optimal operation conditions for lipids production with Nannochloropsis are provided.
Continuous cultures of Nannochloropsis gaditana, Tetraselmis chuii, Tetraselmis suecica and Phaeodactylum tricornutum were carried out at different dilution rates and culture media in order to check their influence on biomass productivity. N. gaditana attained maximum biomass productivity of 0.49g/lday at a dilution rate of 0.421/day. The influence of nitrate concentration on biomass productivity was tested by continuous cultures of N. gaditana. At 8.0mM nitrate and dilution rates ranging between 0.30 and 0.401/day, maximum biomass productivities were achieved. To enhance lipid accumulation, a two-stage culture strategy consisting in a first stage of nitrate-replete conditions followed by a nitrate-depleted phase was performed. The accumulated productivity was 51mgFATTY ACIDS/lday. Results showed an important change in the fatty acids profile and an increase in the neutral lipids content, representing 73.1% of total lipids. Additionally, the combination of nitrogen depletion and light stress was proved to contribute to lipid enhancement.
A comprehensive study of the toxicity of lanthanides (LN) in relation to the media composition will enhance the prediction of their potential adverse effects for living organisms. Here we examined ...the effect of different media on the V. faba root elongation and on the cytotoxic (mitotic index) and the genotoxic (micronucleated cell number) effects from toxicity tests with Ce, Gd and Lu (100, 800 and 6400 μg L−1). Three different exposure media were selected: the standard Hoagland media (SH); an alternative SH, without phosphates (SH-P); and distilled water (DW). In the SH no cyto-genotoxic effects were observed and even, for low LN content, potential root elongation stimulation was reported. The absence of toxic effects was explained by a drastic decrease of the total dissolved LN concentration due to the presence of phosphates causing LN precipitation. In SH-P, LN remained largely soluble and inhibition of root elongation was observed mainly for the highest treatments. While in the tests done in DW, toxic effects were obtained for all treatments. Our results showed that in absence of phosphorous, LN appear mainly as free form and complexed in carbonates and sulphates, and can cause toxic effects, whereas toxicity is not expected when phosphorous is available in aquatic media. The highest LN root contents were observed for the tests using distilled water, possibly due to the absence of competition by Ca2+ for uptake. The present work demonstrated that media composition has a great impact in assessing the ecotoxicology of lanthanides.
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•Lanthanide toxic effects are not expected when phosphorous is present in media.•In test solution without P, LN showed genotoxicity effects in V. faba roots.•Chemical speciation calculations are needed to predict realistic LN toxic effects.•LN has high affinity to complex with PO4, sulphates and carbonates.
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