Publications by authors named "Ana Quevedo"

Fiber-based materials have emerged as a promising option to increase the efficiency of water treatment plants while reducing their environmental impacts, notably by reducing the use of unsustainable chemicals and the size of the settling tank. Cellulose fiber-based super-bridging agents are sustainable, reusable, and versatile materials that considerably improve floc separation in conventional settling tanks or via alternative screening separation methods. In this study, the effectiveness of fiber-based materials for wastewater treatment was evaluated at lab-scale (0.

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We developed a capillary electrophoresis method to separate polystyrene particles (PSPs) with different sizes or different surface functionalities. Separations were performed in buffer and 100 mg L clay or 100 mg L Suwanee River humic acid. In all solutions, PSPs were baseline or near-baseline resolved in less than 15 minutes.

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Objective: To determine if higher levels of circulating interleukin (IL)-15 are positively associated with improvement in insulin resistance in postmenopausal women (PW) with metabolic syndrome (MS).

Methods: According to the median value of IL-15 at baseline, PW older than or equal to 45 years were divided into two groups: higher ( = 43) and lower ( = 42) IL-15. There was a 9-month follow-up period with clinical assessments at baseline and at 9 months (criteria of metabolic syndrome, body fat, and insulin resistance).

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Whether the antibacterial properties of silver nanoparticles (AgNPs) are simply due to the release of silver ions (Ag ) or, additionally, nanoparticle-specific effects, is not clear. We used experimental evolution of the model environmental bacterium Pseudomonas putida to ask whether bacteria respond differently to Ag or AgNP treatment. We pre-evolved five cultures of strain KT2440 for 70 days without Ag to reduce confounding adaptations before dividing the fittest pre-evolved culture into five cultures each, evolving in the presence of low concentrations of Ag , well-defined AgNPs or Ag-free controls for a further 75 days.

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The physicochemical characterization of nanomaterials (NMs) is often an analytical challenge, due to their small size (at least one dimension in the nanoscale, i.e. 1-100 nm), dynamic nature, and diverse properties.

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Evaluation of the uptake pathways in cells during exposure to nanoparticles (NPs) is key for risk assessment and the development of safer nanomaterials, as the internalisation and fate of NPs is linked to their toxicity and mode of action. Here, we determined the uptake mechanisms activated during the internalisation of 10, 30, and 100 nm AgNPs by embryonic zebrafish cells (ZF4). The uptake results demonstrated an NP size- and time-dependent uptake, showing the highest total silver uptake for the smallest AgNP (10 nm) at the lowest exposure concentration (2.

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Cell death is the process that regulates homeostasis and biochemical changes in healthy cells. Silver nanoparticles (AgNPs) act as powerful cell death inducers through the disruption of cellular signalling functions. In this study, embryonic zebrafish cells (ZF4) were used as a potential early-stage aquatic model to evaluate the molecular and cell death mechanisms implicated in the toxicity of AgNPs and Ag.

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In Latin America, there is an increasing interest in the implementation and dissemination of evidence-based, family-centered interventions to prevent youth behavioral problems. While families' participation in interventions is integral to achieving the interventions' desired impact, little is known about what predicts Latin American families' attendance. The current study provides a unique opportunity to explore the participation of families living in the United States, Ecuador, and Chile in an evidence-based intervention, Familias Unidas.

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The response to radiation of polymer gel dosimeters has previously been measured by magnetic resonance imaging (MRI) in terms of changes in the water transverse relaxation rate (R ) or magnetization transfer (MT) parameters. Here we report a new MRI approach, based on detecting nuclear Overhauser enhancement (NOE) mediated saturation transfer effects, which can also be used to detect radiation and measure dose distributions in MAGIC-f (Methacrylic and Ascorbic Acid and Gelatin Initiated by Copper Solution with formaldehyde) polymer gels. Results show that the NOE effects produced by low powered radiofrequency (RF) irradiation at specific frequencies offset from water may be quantified by appropriate measurements and over a useful range depend linearly on the radiation dose.

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The informed consent comprehension process is key to engaging potential research subject participation. The aim of this study is to compare informed consent comprehension between two methods: standard and video-delivered. We compared the in-person and video-delivered informed consent process in the Familias Unidas intervention.

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Purpose: Familias Unidas is an efficacious and effective family-based intervention for preventing and reducing substance use and unsafe sexual behaviors among Latino youth. To facilitate its dissemination, Familias Unidas was shortened from a 12-week intervention to a 6-week intervention and evaluated. We hypothesized that brief Familias Unidas would be efficacious in reducing substance use and unsafe sexual behaviors relative to a comparison condition.

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Background: Lipoprotein(a) [Lp(a)] is a known risk factor for cardiovascular disease, yet its influence on metabolic syndrome (MS) is still controversial. The purpose of this study was to assess the impact generated by this diagnosis in serum Lp(a) concentrations.

Materials And Methods: A total of 1807 subjects of both genders (55.

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Objective: Contribution of a case of penile metastasis in a patient with metastatic rectal carcinoma.

Methods: A 70-Year-old patient was referred to our consultation after the discovery of "penis indurations" having been diagnosed of rectal carcinoma 18 months before. After physical examination penile biopsies were carried out.

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The aim of this work was to evaluate the effects of cadmium on the ovarian parenchyma. An experimental study was designed with 25 Swiss albino mice (healthy females) living 50 days under controlled laboratory conditions. For the experimental group, 21 mice were selected at random and divided into 3 groups (B, C, and D) of 7 animals each; thereafter they were exposed, respectively, to 50, 100 and 150 ppm of cadmium chloride dissolved in water offered ad libitum.

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The purpose of the present study was to assess the impact of occupational exposure to noise and its relationship with other factors that can induce hearing loss in the electric plant workers of a petrochemical industry of the west of Venezuela. A cross-sectional study was conducted that included sonometry tests, carried out according to the established methodology by COVENIN rules, and the occupational medical evaluation and liminal tonal audiometrics test in 75 workers. The equivalent noise levels (Leq) was quantified in different workplaces.

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Vibrio vulnificus produces serious illnesses that are commonly associated with shellfish consumption, particularly raw oysters. Ingestion can result in fatal septicemia in susceptible individuals with hepatitis, cirrhosis, immune dysfunction, diabetes, or hemochromatosis (metabolic iron overload). Therefore, postharvest treatments to reduce vibrio levels in oysters have been recommended.

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