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1.
Phys Rev Lett ; 132(13): 136301, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613271

RESUMO

We study noninteracting fermionic systems undergoing continuous monitoring and driven by biased reservoirs. Averaging over the measurement outcomes, we derive exact formulas for the particle and heat flows in the system. We show that these currents feature competing elastic and inelastic components, which depend nontrivially on the monitoring strength γ. We highlight that monitor-induced inelastic processes lead to nonreciprocal currents, allowing one to extract work from measurements without active feedback control. We illustrate our formalism with two distinct monitoring schemes providing measurement-induced power or cooling. Optimal performances are found for values of the monitoring strength γ, which are hard to address with perturbative approaches.

2.
Biomacromolecules ; 24(9): 4180-4189, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37606546

RESUMO

Chitin nanocrystals (ChNCs) are unique to all other bio-derived nanomaterials in one aspect: the inherent presence of a nitrogen moiety. By tuning the chemical functionality of this nanomaterial, and thus its charge and hydrogen bonding capacity, one can heavily impact its macroscopic properties such as its rheological and self-assembly characteristics. In this study, two types of ChNCs are made using acid hydrolysis (AH-ChNCs) and oxidative (OX-ChNCs) pathways, unto which deacetylation using a solvent-free procedure is utilized to create chitosan nanocrystals (ChsNCs) of varying degree of deacetylation (DDA). These nanocrystals were then studied for their rheological behavior and liquid crystalline ordering. It was found that with both deacetylation and carboxylation of ChNCs, viscosity continually increased with increasing concentrations from 2 to 8 wt %, contrary to AH-ChNC dispersions in the same range. Interestingly, increasing the amine content of ChNCs was not proportional to the storage modulus, where a peak saturation of amines provided the most stiffness. Conversely, while the introduction of carboxylation increased the elastic modulus of OX-ChNCs by an order of magnitude from that of AH-ChNCs, it was decreased by increasing DDA. Deacetylation and carboxylation both inhibited the formation of a chiral nematic phase. Finally, these series of nanocrystals were incorporated into biodegradable pectin-alginate films as a physical reinforcement, which showed increased tensile strength and Young's modulus values for the films incorporated with ChsNCs. Overall, this study is the first to investigate how surface functionalization of chitin-derived nanocrystals can affect their rheological and liquid crystalline properties and how it augments pectin/alginate films as a physical reinforcement nanofiller.


Assuntos
Quitosana , Nanopartículas , Quitina , Biopolímeros , Pectinas , Alginatos , Aminas
3.
Phys Rev Lett ; 129(26): 260603, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36608188

RESUMO

We introduce and study a new model consisting of a single classical random walker undergoing continuous monitoring at rate γ on a discrete lattice. Although such a continuous measurement cannot affect physical observables, it has a nontrivial effect on the probability distribution of the random walker. At small γ, we show analytically that the time evolution of the latter can be mapped to the stochastic heat equation. In this limit, the width of the log-probability thus follows a Family-Vicsek scaling law, N^{α}f(t/N^{α/ß}), with roughness and growth exponents corresponding to the Kardar-Parisi-Zhang (KPZ) universality class, i.e., α_{KPZ}^{1D}=1/2 and ß_{KPZ}^{1D}=1/3, respectively. When γ is increased outside this regime, we find numerically in 1D a crossover from the KPZ class to a new universality class characterized by exponents α_{M}^{1D}≈1 and ß_{M}^{1D}≈1.4. In 3D, varying γ beyond a critical value γ_{M}^{c} leads to a phase transition from a smooth phase that we identify as the Edwards-Wilkinson class to a new universality class with α_{M}^{3D}≈1.

4.
Chem Rev ; 120(2): 986-1041, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31725267

RESUMO

Localized surface plasmon resonance (LSPR) is a physical phenomenon exhibited by nanoparticles of metals including coinage metals, alkali metals, aluminum, and some semiconductors which translates into electromagnetic, thermal, and chemical properties. In the past decade, LSPR has been taken advantage of in the context of catalysis. While plasmonic nanoparticles (PNPs) have been successfully applied toward enhancing catalysis of inorganic reactions such as water splitting, they have also demonstrated exciting performance in the catalysis of organic transformations with potential applications in synthesis of molecules from commodity to pharmaceutical compounds. The advantages of this approach include improved selectivity, enhanced reaction rates, and milder reaction conditions. This review provides the basics of LSPR theory, details the mechanisms at play in plasmon-enhanced nanocatalysis, sheds light onto such nanocatalyst design, and finally systematically presents the breadth of organic reactions hence catalyzed.

5.
Angew Chem Int Ed Engl ; 61(42): e202207206, 2022 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-36006856

RESUMO

To unlock nature's potential for functional biomaterials, many efforts have been devoted to isolating the nanocrystalline domains within the supramolecular structure of polysaccharides. Yet, low reactivity and yield in aqueous systems along with excessive solvent usage hinders its development. In this report, the first solvent-free pathway to access carboxylated chitin and cellulose nanocrystals with excellent mass balance is described, relying on a new method coined high-humidity shaker aging (HHSA). The method involves a mild grinding of the polysaccharide with ammonium persulfate followed by an aging phase under high-humidity and on a shaker plate. Insights into the mechanism were uncovered, which highlighted the unique role of high humidity to afford a gradual uptake of water by the material up to deliquescence when the reaction is complete. This process was then validated for direct synthesis of nanocrystals from biomass sources including crab and soft wood pulp.


Assuntos
Celulose , Nanopartículas , Materiais Biocompatíveis , Celulose/química , Quitina/química , Umidade , Nanopartículas/química , Polissacarídeos/química , Água
6.
Compr Rev Food Sci Food Saf ; 20(6): 6027-6056, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34435448

RESUMO

The active packaging materials fabricated using natural polymers is increasing in recent years. Electrohydrodynamic processing has drawn attention in active food packaging due to its potential in fabricating materials with advanced structural and functional properties. These materials have the significant capability in enhancing food's quality, safety, and shelf-life. Through electrospinning and electrospray, fibers and particles are encapsulated with bioactive compounds for active packaging applications. Understanding the principle behind electrohydrodynamics provides fundamentals in modulating the material's physicochemical properties based on the operating parameters. This review provides a deep understanding of electrospray and electrospinning, along with their advantages and recent innovations, from food packaging perspectives. The natural polymers suitable for developing active packaging films and coatings through electrohydrodynamics are intensely focused. The critical properties of the packaging system are discussed with characterization techniques. Furthermore, the limitations and prospects for natural polymers and electrohydrodynamic processing in active packaging are summarized.


Assuntos
Embalagem de Alimentos , Polímeros
7.
Compr Rev Food Sci Food Saf ; 20(5): 5258-5282, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34318596

RESUMO

Microbial growth and fluctuations in environmental conditions have been shown to cause microbial contamination and deterioration of food. Thus, it is paramount to develop reliable strategies to effectively prevent the sale and consumption of contaminated or spoiled food. Responsive packaging systems are designed to react to specific stimuli in the food or environment, such as microorganisms or temperature, then implement an informational or corrective response. Informative responsive packaging is aimed at continuously monitoring the changes in food or environmental conditions and conveys this information to the users in real time. Meanwhile, packaging systems with the capacity to control contamination or deterioration are also of great interest. Encouragingly, corrective responsive packaging attempting to mitigate the adverse effects of condition fluctuations on food has been investigated. This packaging exerts its effects through the triggered release of active agents by environmental stimuli. In this review, informative and corrective responsive packaging is conceptualized clearly and concisely. The mechanism and characteristics of each type of packaging are discussed in depth. This review also summarized the latest research progress of responsive packaging and objectively appraised their advantages. Evidently, the mechanism through which packaging systems respond to microbial contamination and associated environmental factors was also highlighted. Moreover, risk concerns, related legislation, and consumer perspective in the application of responsive packaging are discussed as well. Broadly, this comprehensive review covering the latest information on responsive packaging aims to provide a timely reference for scientific research and offer guidance for presenting their applications in food industry.


Assuntos
Embalagem de Alimentos , Conservação de Alimentos , Fazendas , Contaminação de Alimentos/prevenção & controle , Qualidade dos Alimentos
8.
Phys Rev Lett ; 125(4): 040603, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32794778

RESUMO

We introduce the asymmetric extension of the quantum symmetric simple exclusion process which is a stochastic model of fermions on a lattice hopping with random amplitudes. In this setting, we analytically show that the time-integrated current of fermions defines a height field that exhibits quantum nonlinear stochastic Kardar-Parisi-Zhang dynamics. Similarly to classical simple exclusion processes, we further introduce the discrete Cole-Hopf (or Gärtner) transform of the height field that satisfies a quantum version of the stochastic heat equation. Finally, we investigate the limit of the height field theory in the continuum under the celebrated Kardar-Parisi-Zhang scaling and the regime of almost-commuting quantum noise.

9.
Biomacromolecules ; 21(6): 2236-2245, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-32223230

RESUMO

In this study, we demonstrate for the first time the fabrication of carboxylated chitosan nanocrystals (ChsNC) with high degree of deacetylation (DDA) at >80% and narrow size distribution. We also studied its application as a sustainable support material for metal-based catalysts. Carboxylated chitin nanocrystals (ChNCs) were initially prepared through partial cleavage of glycosidic bonds in chitin by ammonium persulfate, with concurrent oxidation of chitin C6 primary alcohols to produce carboxylate groups on the surface of the ChNCs. ChsNCs were subsequently prepared using an alkaline deacetylation procedure in the presence of NaBH4 to preserve the nanorod structure of the biomaterial. The resulting nanocrystals feature both carboxyl and amino functional groups. Transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) spectroscopy were used to determine the morphology and composition of these carboxylated ChNCs and ChsNCs. Subsequently, we tested the ability of the as-made ChsNCs as a biomass-based catalyst support for Au nanoparticles (NPs) using the 4-nitrophenol reduction and the aldehyde-amine-alkyne (A3) coupling reactions to demonstrate its capabilities in regard to the ones of cellulose nanocrystals (CNCs). In particular, Au NPs over ChsNCs featured the highest turnover frequency (TOF) value for the 4-nitrophenol reduction reported for all Au-based catalysts supported on carbon-based systems. Spectroscopic and imaging techniques confirmed the importance of precisely controlling the redox state of Au as it is being deposited to afford a highly disperse active site on the bionano-support.


Assuntos
Quitosana , Nanopartículas Metálicas , Catálise , Celulose , Ouro , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Beilstein J Org Chem ; 16: 2477-2483, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33093927

RESUMO

In this report, chitin and chitosan nanocrystals were used as biomass-based supports for Pd nanoparticles (NPs) used as a heterogeneous catalyst for the Heck coupling reaction. By using a one-pot fabrication method, a Pd salt precursor was directly reduced and deposited onto these nanocrystal catalysts. Characterization of these nanocomposites showed disperse Pd NPs on the surfaces of the chitinous nanocrystals. Heck coupling model reactions revealed full product yield in relatively benign conditions, outcompeting the use of other catalysts supported on biomass-based nanomaterials, including cellulose nanocrystals. These initial results show the potential for using chitinous nanomaterials as effective catalyst supports in cross-coupling reactions.

11.
Phys Rev Lett ; 123(8): 080601, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31491217

RESUMO

We present the solution to a model of fermions hopping between neighboring sites on a line with random Brownian amplitudes and open boundary conditions driving the system out of equilibrium. The average dynamics reduces to that of the symmetric simple exclusion process. However, the full distribution encodes for a richer behavior, entailing fluctuating quantum coherences which survive in the steady limit. We determine exactly the steady statistical distribution of the system state. We show that the out-of-equilibrium quantum coherence fluctuations satisfy a large-deviation principle, and we present a method to recursively compute exactly the large-deviation function. As a by-product, our approach gives a solution of the classical symmetric simple exclusion process based on fermion technology. Our results open the route towards the extension of the macroscopic fluctuation theory to many-body quantum systems.

12.
Hum Brain Mapp ; 39(11): 4420-4439, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30113112

RESUMO

This study aimed to identify biomarkers of major depressive disorder (MDD), by relating neuroimage-derived measures to binary (MDD/control), ordinal (severe MDD/mild MDD/control), or continuous (depression severity) outcomes. To address MDD heterogeneity, factors (severity of psychic depression, motivation, anxiety, psychosis, and sleep disturbance) were also used as outcomes. A multisite, multimodal imaging (diffusion MRI [dMRI] and structural MRI [sMRI]) cohort (52 controls and 147 MDD patients) and several modeling techniques-penalized logistic regression, random forest, and support vector machine (SVM)-were used. An additional cohort (25 controls and 83 MDD patients) was used for validation. The optimally performing classifier (SVM) had a 26.0% misclassification rate (binary), 52.2 ± 1.69% accuracy (ordinal) and r = .36 correlation coefficient (p < .001, continuous). Using SVM, R2 values for prediction of any MDD factors were <10%. Binary classification in the external data set resulted in 87.95% sensitivity and 32.00% specificity. Though observed classification rates are too low for clinical utility, four image-based features contributed to accuracy across all models and analyses-two dMRI-based measures (average fractional anisotropy in the right cuneus and left insula) and two sMRI-based measures (asymmetry in the volume of the pars triangularis and the cerebellum) and may serve as a priori regions for future analyses. The poor accuracy of classification and predictive results found here reflects current equivocal findings and sheds light on challenges of using these modalities for MDD biomarker identification. Further, this study suggests a paradigm (e.g., multiple classifier evaluation with external validation) for future studies to avoid nongeneralizable results.


Assuntos
Encéfalo/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Imageamento por Ressonância Magnética , Imagem Multimodal , Adulto , Estudos de Coortes , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Máquina de Vetores de Suporte
13.
Hum Brain Mapp ; 38(9): 4370-4385, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28594150

RESUMO

BACKGROUND: Reduced cortical thickness is a candidate biological marker of depression, although findings are inconsistent. This could reflect analytic heterogeneity, such as use of region-wise cortical thickness based on the Freesurfer Desikan-Killiany (DK) atlas or surface-based morphometry (SBM). The Freesurfer Destrieux (DS) atlas (more, smaller regions) has not been utilized in depression studies. This could also reflect differential gender and age effects. METHODS: Cortical thickness was collected from 170 currently depressed adults and 52 never-depressed adults. Visually inspected and approved Freesurfer-generated surfaces were used to extract cortical thickness estimates according to the DK atlas (68 regions) and DS atlas (148 regions) for region-wise analysis (216 total regions) and for SBM. RESULTS: Overall, except for small effects in a few regions, the two region-wise approaches generally failed to discriminate depressed adults from nondepressed adults or current episode severity. Differential effects by age and gender were also rare and small in magnitude. Using SBM, depressed adults showed a significantly thicker cluster in the left supramarginal gyrus than nondepressed adults (P = 0.047) but there were no associations with current episode severity. CONCLUSIONS: Three analytic approaches (i.e., DK atlas, DS atlas, and SBM) converge on the notion that cortical thickness is a relatively weak discriminator of current depression status. Differential age and gender effects do not appear to represent key moderators. Robust associations with demographic factors will likely hinder translation of cortical thickness into a clinically useful biomarker. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc. Hum Brain Mapp 38:4370-4385, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Adolescente , Adulto , Fatores Etários , Idoso , Córtex Cerebral/patologia , Transtorno Depressivo Maior/patologia , Transtorno Depressivo Maior/terapia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença , Fatores Sexuais , Adulto Jovem
14.
J Food Sci Technol ; 54(1): 260-266, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28242924

RESUMO

Fresh coriander leaves are highly perishable in nature and their sensory quality and nutritional value decreases without proper processing or preservation. In the present study, three aqueous solutions of sodium hypochlorite (SH, 100 mg/L), chlorine dioxide (CD, 10 mg/L), and sodium butyl p-hydroxybenzoate (SBPH, 12 mg/L), and tap water, were used to treat fresh coriander for 15 min. The treated samples were packed in PVC boxes with ambient air under packaged under passive modified atmosphere packaging conditions and stored at 4 °C for 10 days. Effects of washing treatments on color, total chlorophyll contents, ascorbic acid contents, total contents of phenolic compounds, and total aerobic bacterial counts (APC) were investigated. CD treatment has the least detrimental effects on color, total chlorophyll contents and ascorbic acid contents of fresh coriander, followed by SH treatment. In addition, CD treatment showed a greater reduction in APC and maintained the microbial load at lower levels than other treatments during the 10-day storage period.

15.
Hum Brain Mapp ; 36(9): 3472-85, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26033168

RESUMO

In the last decade, many studies have used automated processes to analyze magnetic resonance imaging (MRI) data such as cortical thickness, which is one indicator of neuronal health. Due to the convenience of image processing software (e.g., FreeSurfer), standard practice is to rely on automated results without performing visual inspection of intermediate processing. In this work, structural MRIs of 40 healthy controls who were scanned twice were used to determine the test-retest reliability of FreeSurfer-derived cortical measures in four groups of subjects-those 25 that passed visual inspection (approved), those 15 that failed visual inspection (disapproved), a combined group, and a subset of 10 subjects (Travel) whose test and retest scans occurred at different sites. Test-retest correlation (TRC), intraclass correlation coefficient (ICC), and percent difference (PD) were used to measure the reliability in the Destrieux and Desikan-Killiany (DK) atlases. In the approved subjects, reliability of cortical thickness/surface area/volume (DK atlas only) were: TRC (0.82/0.88/0.88), ICC (0.81/0.87/0.88), PD (0.86/1.19/1.39), which represent a significant improvement over these measures when disapproved subjects are included. Travel subjects' results show that cortical thickness reliability is more sensitive to site differences than the cortical surface area and volume. To determine the effect of visual inspection on sample size required for studies of MRI-derived cortical thickness, the number of subjects required to show group differences was calculated. Significant differences observed across imaging sites, between visually approved/disapproved subjects, and across regions with different sizes suggest that these measures should be used with caution.


Assuntos
Córtex Cerebral/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Reconhecimento Automatizado de Padrão/métodos , Software , Adolescente , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Tamanho do Órgão , Reprodutibilidade dos Testes , Adulto Jovem
16.
Heliyon ; 10(3): e24901, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38314263

RESUMO

Phenolic branched-chain fatty acid (PBC-FA) emulsion was produced by dissolving it in ethanol and mixing with water (pH 7). The resulting monodispersed emulsion droplets were approximately 200 nm in diameter. The stability of the emulsion was evaluated by storing it at 4 and 20 °C for 30 days. The antimicrobial activity of the PBC-FA emulsion was tested against Escherichia coli and Listeria innocua (8 log CFU/mL) by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using a microdilution method. The PBC-FA was effective against L. innocua with MIC and MBC of 14.1 µg/mL and caused membrane permeation as determined with SEM and Live/Dead cell assay, but was not effective against E. coli O157:H7 at the tested concentrations (5-250 µg/mL). We also evaluated PBC-FA emulsion's potential to be used as a wash against L. innocua inoculated on apples. The results showed that the 500 µg/mL PBC-FA emulsion with 5 % ethanol had equivalent antimicrobial activity (2-3 logs reductions) against L. innocua as the 20 µg/mL chlorine solution, a commonly used sanitizer. 500 µg/mL PBC-FA emulsion had better antimicrobial efficacy when organic matter (chemical oxygen demand: 9.0 g/L) was present compared to 20 µg/mL of chlorine. The effect of PBC-FA on the quality of the apples, was determined by measuring changes in color, firmness, and soluble solids content over a 14-day storage period at 20 °C. The quality of the apples was not affected by PBC-FA over the 14-day storage period, suggesting that PBC-FA emulsion can be used as a wash for apples without affecting their quality.

17.
Int J Food Microbiol ; 419: 110748, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38772217

RESUMO

An antimicrobial coating was produced by mixing phenolic branched-chain fatty acid (PBC-FA) with glycerol and a carboxymethyl cellulose solution (CMC) at pH 7. The resulting PBC-FA-CMC solution formed an emulsion with an average droplet size of 77 nm. The emulsion in the coating solution was stable for at least 30 days at 20 °C. The in vitro antimicrobial activity of the film formed from the PBC-FA emulsion was tested against a mixture of 3 strains of Listeria innocua (7 log CFU/mL). Film with a concentration of 1000 µg/mL of PBC-FA effectively reduced the population of L. innocua below the limit of detection (<1.48 log CFU/mL) in vitro. The effect of the 1000 µg/mL PBC-FA-CMC coating formulation was then evaluated against L. innocua inoculated on "Gala" apples. Results showed that compared with the non-coated control, the coating reduced L. innocua populations by ~2 log CFU/fruit and ~6 log CFU/fruit on the apple when enumerated on tryptic soy agar and selective media (PALCAM), respectively, indicating that PBC-FA applied as a coating on apples resulted in the sub-lethal injury of bacterial cells. When L. innocua was inoculated onto PBC-FA-coated apples, the L. innocua population decreased by ~4 log CFU/fruit during 14 days of shelf-life at 20 °C. The PBC-FA coating lowered the moisture loss but did not affect the color, firmness, or soluble solids content of apples during the 14-day at 20 °C. Overall, this study revealed that there is a potential that PBC-FA can be used as an antimicrobial coating to inactivate Listeria and preserve the quality of apples.


Assuntos
Listeria , Malus , Listeria/efeitos dos fármacos , Listeria/crescimento & desenvolvimento , Malus/microbiologia , Frutas/microbiologia , Ácidos Graxos/farmacologia , Conservação de Alimentos/métodos , Microbiologia de Alimentos , Contagem de Colônia Microbiana , Fenóis/farmacologia
18.
J Food Prot ; 87(7): 100297, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38734414

RESUMO

Salmonella is capable of surviving dehydration within various foods, such as dried fruit. Dried fruit, including apple slices, have been the subject of product recalls due to contamination with Salmonella. A study was conducted to determine the fate of Salmonella on apple slices, following immersion in three antimicrobial solutions (viz., ε-polylysine [epsilon-polylysine or EP], sodium bisulfate [SBS], or peracetic acid [PAA]), and subsequent hot air dehydration. Gala apples were aseptically cored and sliced into 0.4 cm thick rings, bisected, and inoculated with a five-strain composite of desiccation-resistant Salmonella, to a population of 8.28 log CFU/slice. Slices were then immersed for 2 min in various concentrations of antimicrobial solutions, including EP (0.005, 0.02, 0.05, and 0.1%), SBS (0.05, 0.1, 0.2, and 0.3%), PAA (18 or 42 ppm), or varying concentrations of PAA + EP, and then dehydrated at 60°C for 5 h. Salmonella populations in positive control samples (inoculated apple slices washed in sterile water) declined by 2.64 log after drying. In the present study, the inactivation of Salmonella, following EP and SBS treatments, increased with increasing concentrations, with maximum reductions of 3.87 and 6.20 log (with 0.1 and 0.3% of the two compounds, respectively). Based on preliminary studies, EP concentrations greater than 0.1% did not result in lower populations of Salmonella. Pretreatment washes with either 18 or 42 ppm of PAA inactivated Salmonella populations by 4.62 and 5.63 log, respectively, following desiccation. Combining PAA with up to 0.1% EP induced no greater population reductions of Salmonella than washing with PAA alone. The addition of EP to PAA solutions appeared to destabilize PAA concentrations, reducing its biocidal efficacy. These results may provide antimicrobial predrying treatment alternatives to promote the reduction of Salmonella during commercial or consumer hot air drying of apple slices.


Assuntos
Contagem de Colônia Microbiana , Microbiologia de Alimentos , Malus , Ácido Peracético , Polilisina , Salmonella , Malus/microbiologia , Ácido Peracético/farmacologia , Salmonella/efeitos dos fármacos , Polilisina/farmacologia , Humanos , Sulfatos/farmacologia , Conservação de Alimentos/métodos , Relação Dose-Resposta a Droga , Dessecação , Contaminação de Alimentos/análise , Manipulação de Alimentos/métodos , Qualidade de Produtos para o Consumidor
19.
Surv Ophthalmol ; 68(4): 601-614, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36931437

RESUMO

We compare efficacy of treatments for chronic central serous chorioretinopathy (CSCR) > 3 months. Four treatment classes were considered: photodynamic therapy (PDT), subthreshold laser therapies (SLT), mineralocorticoid receptor antagonists (MRA) and antivascular endothelial growth factor (anti-VEGF) agents. Pairwise and network meta-analyses (NMA) of the primary outcomes (complete resolution of subretinal fluid (SRF), mean change in best corrected visual acuity (BCVA as logMAR) and mean change in SRF) and secondary outcomes (mean change in central retinal thickness, and central choroidal thickness (µm), recurrence of SRF, and adverse events) at 3, 6, and 12 months were compared. Confidence in Network Meta-Analysis (CINeMA) informed the certainty of NMA evidence. Eleven RCTs of 458 eyes (450 patients) were included. NMA at 3 months showed that both PDT and SLT were superior to control for resolution of SRF (OR 4.83; 95% CI 1.72-13.55 and 2.27; 1.14-4.49, respectively) and SLT was superior to control for improving BCVA (MD -0.10; -0.17 to -0.04). PDT was superior to SLT for improving CRT (MD -42.88; -75.27 to -10.50). On probability ranking, PDT and SLT were consistently the best-ranked treatments for each outcome at 3 months, but low confidence of evidence and paucity of studies preclude definitive conclusions.


Assuntos
Coriorretinopatia Serosa Central , Terapia a Laser , Fotoquimioterapia , Humanos , Coriorretinopatia Serosa Central/terapia , Metanálise em Rede , Retina , Tomografia de Coerência Óptica , Fármacos Fotossensibilizantes/uso terapêutico , Doença Crônica , Angiofluoresceinografia , Estudos Retrospectivos , Resultado do Tratamento
20.
Foods ; 12(23)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38231609

RESUMO

This study investigated the mechanism of how lauric arginate ethyl ester (LAE) improves the photoinactivation of bacteria by curcumin after diluting the 100 µmol/L stock curcumin-LAE micelle solution to the concentration used during the treatment based on the curcumin concentration. The photoinactivation of bacteria was conducted by irradiating the 1 µmol/L curcumin-LAE solution containing cocktails of Escherichia coli and Listeria innocua strains (7 log CFU/mL) for 5 min with UV-A light (λ = 365 nm). The changes in solution turbidity, curcumin stability, and bacterial morphology, viability, and recovery were observed using SEM, TEM, and live/dead cell assays. The study found that LAE enhances the photoinactivation of bacteria by increasing the permeability of cell membranes which could promote the interaction of reactive oxygen species produced by photosensitized curcumin with the cell components. The combination of curcumin and LAE was demonstrated to be more effective in inhibiting bacterial recovery at pH 3.5 for E. coli, while LAE alone was more effective at pH 7.0 for L. innocua.

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