151 results match your criteria: "Pontifical Catholic University of Rio de Janeiro - PUC-Rio[Affiliation]"

Arsenic (As) causes health effects, especially cancer. Rice ( L.) can contain high As concentrations.

View Article and Find Full Text PDF

Santa Lucía peloid is a sediment used in pelotherapy in Cuban primary health care services. Therefore, in addition to physicochemical regulated parameters, other analyses are required to complement their physicochemical characterization and understand potential element mobility, radiological risk, and toxicity as well as likely bioactive compounds present in Santa Lucía peloid. For these purposes, inorganic and organic elements and compounds were considered to evaluate Santa Lucía peloid's quality.

View Article and Find Full Text PDF
Article Synopsis
  • * The proposed methodology uses advanced techniques like adaptive template matching, IMSLIC, and convolutional neural networks to automate the detection of the spinal cord in CT images, reducing human error and making the process more efficient.
  • * Testing on 36 CT images showed high accuracy (92.55%), specificity (92.87%), and sensitivity (89.23%) for spinal cord detection, indicating that this computational approach is effective for treatment planning in radiotherapy.
View Article and Find Full Text PDF

The addition of 2-bromobenzylmagnesium bromide to chiral N- tert-butanesulfinyl imines derived from tetralone-type ketones proceeds with high levels of diastereocontrol. The resulting sulfinamide derivatives were transformed into dibenzoazaspiro compounds after a palladium-catalyzed intramolecular N-arylation. DFT calculations have been performed to rationalize the stereochemical course of the reaction.

View Article and Find Full Text PDF

This is a description of the indirect determination of kanamycin sulfate though the photoluminescence enhancement of an aqueous dispersion of amino-functionalized graphene quantum dots (amino-GQDs) coupled with gold nanoparticles (AuNPs) in a cationic surfactant-rich medium. Specifically, cetyltrimethylammonium bromide (CTAB) was used as the cationic surfactant in our work. Previously, solid phase extraction with a cartridge packed with aminoglycoside-selective imprinted polymer ensured selectivity in kanamycin determination in yellow-fever vaccine and veterinary pharmaceutical samples.

View Article and Find Full Text PDF

The most commonly used solution in chrome plating bath is chromic acid (hexavalent Cr), and a considerable amount of mists is released into the air and consequently produce hazards to workers. Thus, the aim of this study was to evaluate whether the biomarker of exposure to metals, specially Cr levels, presents associations with hematological and biochemical parameters and if they can alter the activity of enzymes that contain thiol groups such as pyruvate kinase, creatine kinase, adenylate kinase, and δ-aminolevulinate dehydratase. Fifty male chrome plating workers were used for exposed group and 50 male non-exposed workers for control group.

View Article and Find Full Text PDF

The environmental costs and benefits of high-yield farming.

Nat Sustain

September 2018

Conservation Science Group, Department of Zoology, Downing St, Cambridge CB2 3EJ, UK.

How we manage farming and food systems to meet rising demand is pivotal to the future of biodiversity. Extensive field data suggest impacts on wild populations would be greatly reduced through boosting yields on existing farmland so as to spare remaining natural habitats. High-yield farming raises other concerns because expressed per unit area it can generate high levels of externalities such as greenhouse gas (GHG) emissions and nutrient losses.

View Article and Find Full Text PDF

After publication, it was highlighted that the original publication [1] contained a spelling mistake in the first name of Marcelo Gattas. This was incorrectly captured as Marelo Gattass in the original article which has since been updated.

View Article and Find Full Text PDF

Are metals and pyrene levels additional factors playing a pivotal role in air pollution-induced inflammation in taxi drivers?

Toxicol Res (Camb)

January 2018

Laboratory of Toxicology (LATOX) , Department of Analysis , Universidade Federal do Rio Grande do Sul , Av. Ipiranga 2752 , 90610-000 , Porto Alegre , RS , Brazil . Email: ; ; Tel: (+55)51 3308-5297.

This study aimed to evaluate which xenobiotic (As, Hg, Pb or pyrenes) is primarily responsible for the inflammatory process in taxi drivers. Multiple regression analysis showed that Hg is the main xenobiotic responsible for the increase of cytokine levels. These associations suggest that co-exposure to pollutants could be a risk factor for health effects.

View Article and Find Full Text PDF

Optimization of sugarcane bagasse pretreatment using alkaline hydrogen peroxide through ANN and ANFIS modelling.

Bioresour Technol

November 2018

Department of Chemical and Materials Engineering (DEQM), Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rua Marquês de São Vicente, 225 - Gávea, Rio de Janeiro, RJ 22451-900, Brazil. Electronic address:

The present study compares the optimization using Artificial Neural Networks (ANN) and Adaptive Network-based Fuzzy Inference System (ANFIS) in the sugarcane bagasse delignification process using Alkaline Hydrogen Peroxide (AHP). Two variables were assessed experimentally: temperature (25-45 °C) and hydrogen peroxide concentration (1.5-7.

View Article and Find Full Text PDF

In the present study, in situ lichens (Flavoparmelia caperata) were used to assess the deposition of atmospheric trace elements in the metropolitan area of Huancayo (Junín, Peru). In total, ten sampling sites were chosen and categorized as urban, peri-urban (rural-urban) and rural areas according to land use. In addition, samples were also collected from a non-contaminated area categorized as a control site.

View Article and Find Full Text PDF

The determination of kanamycin sulfate was made indirectly by measuring its effect on photoluminescent amino functionalized graphene quantum dots (GQDs-amino) associated with gold nanoparticles (AuNPs) that were produced by the reduction of AuCl with NaBH in an aqueous dispersion of GQDs-amino (obtained by the pyrolysis of citric acid and glutathione) also containing the cationic surfactant CTAB. The AuNPs-GQDs-amino-CTAB system presents a suppressed photoluminescence that is amplified in the presence of kanamycin. Under optimized experimental conditions, the photoluminescence amplification of the nanomaterial system showed a linear response as a function of kanamycin concentration, covering three orders of magnitude (10 to 10 mol L).

View Article and Find Full Text PDF
Article Synopsis
  • * A deep learning technique combined with the particle swarm optimization (PSO) algorithm was employed to optimize neural network hyperparameters without manual adjustments.
  • * Testing on CT scans yielded impressive results with 97.62% accuracy, demonstrating the effectiveness of the PSO algorithm in enhancing sensitivity and reducing false positives in nodule classification.
View Article and Find Full Text PDF
Article Synopsis
  • * This study introduces a new diagnostic methodology for lung nodules that uses image processing and pattern recognition, specifically employing mean phylogenetic distance and taxonomic diversity index as texture descriptors.
  • * The methodology was tested on CT images with impressive results: sensitivity (93.42%), specificity (91.21%), accuracy (91.81%), and an area under the ROC curve of 0.94, indicating its strong performance in distinguishing between benign and malignant tumors.
View Article and Find Full Text PDF

Unlabelled: Cognitive impairment in Parkinson's disease (PD) results in significant morbidity and mortality being early diagnosis essential. Identification of patients who are at higher risk of developing cognitive impairment based only on clinical data is not sufficient. To this end, magnetic resonance imaging (MRI) with automatic segmentation, such as FreeSurfer, could be a useful tool with high accuracy because it has histological validation.

View Article and Find Full Text PDF
Article Synopsis
  • * It utilizes the DDSM database and includes a two-phase methodology: training (classifying breast tissue and regions) and testing (involves various preprocessing steps and false positive reductions).
  • * The results indicate high accuracy rates, with over 95% in classifying breast tissue and strong sensitivity and specificity in detecting mass regions, demonstrating the effectiveness of the proposed method.
View Article and Find Full Text PDF

Stabilization of spherical nanoparticles of iron(III) hydroxides in aqueous solution by wormlike micelles.

J Colloid Interface Sci

March 2018

Department of Physical-Chemistry, Institute of Chemistry, University of Campinas, P.O. BOX 6154, 13084-862 Campinas, SP, Brazil. Electronic address:

Hypothesis: The low K value of Fe(OH) (3 × 10 at 298 K) explain the immediate coagulation when the pH of a solution of Fe(III) is adjusted to 7. However, stable dispersions of Fe(OH) can be formed when the pH is adjusted to 7 in the presence of wormlike micelles formed by cetyltrimethylammonium bromide and sodium salicylate. The formation of a structure containing Fe(OH) nanoparticles decorating wormlike micelles is responsible for the high stability of the dispersions.

View Article and Find Full Text PDF

This work reports on the preparation and characterization of anisotropic composition nanoparticles based on the electrostatic binding of dodecyltrimethylammonium surfactant to poly(acrylic acid) blocks of diblock copolymers with poly(ethylene oxide) (PEO) and poly(-isopropyl acrylamide) (PNIPAm). These nanoparticles form kinetically stable dispersions and display liquid-crystalline cores with a micellar cubic structure, as determined by small-angle X-ray scattering. Mixtures with different proportions of the two block copolymers and stoichiometric amounts of CTA were prepared and their behavior was compared with that of the parent nanoparticles.

View Article and Find Full Text PDF

Neural network modeling to support an experimental study of the delignification process of sugarcane bagasse after alkaline hydrogen peroxide pre-treatment.

Bioresour Technol

November 2017

Department of Chemical and Materials Engineering (DEQM), Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rua Marquês de São Vicente, 225 - Gávea, Rio de Janeiro, RJ 22430-060, Brazil. Electronic address:

The present study examines the use of Artificial Neural Networks (ANN) as prediction and fault detection tools for the delignification process of sugarcane bagasse via hydrogen peroxide (HO). Experimental conditions varied from 25 to 45°C for temperature and from 1.5% to 7.

View Article and Find Full Text PDF

Lung cancer is pointed as the major cause of death among patients with cancer throughout the world. This work is intended to develop a methodology for diagnosis of lung nodules using images from the Image Database Consortium and Image Database Resource Initiative (LIDC-IDRI). The proposed methodology uses image processing and pattern recognition techniques.

View Article and Find Full Text PDF

Few studies have evaluated magnetic resonance imaging (MRI) visual scales in Parkinson's disease-Mild Cognitive Impairment (PD-MCI). We selected 79 PD patients and 92 controls (CO) to perform neurologic and neuropsychological evaluation. Brain MRI was performed to evaluate the following scales: Global Cortical Atrophy (GCA), Fazekas, and medial temporal atrophy (MTA).

View Article and Find Full Text PDF

Background: Although there have been significant advances in network, hardware, and software technologies, the health care environment has not taken advantage of these developments to solve many of its inherent problems. Research activities in these 3 areas make it possible to apply advanced technologies to address many of these issues such as real-time monitoring of a large number of patients, particularly where a timely response is critical.

Objective: The objective of this research was to design and develop innovative technological solutions to offer a more proactive and reliable medical care environment.

View Article and Find Full Text PDF

Background And Objective: Lung cancer remains one of the most common cancers globally. Temporal evaluation is an important tool for analyzing the malignant behavior of lesions during treatment, or of indeterminate lesions that may be benign. This work proposes a methodology for the analysis, quantification, and visualization of small (local) and large (global) changes in lung lesions.

View Article and Find Full Text PDF

Background And Objective: Medical image processing can contribute to the detection and diagnosis of human body anomalies, and it represents an important tool to assist in minimizing the degree of uncertainty of any diagnosis, while providing specialists with an additional source of diagnostic information. Strabismus is an anomaly that affects approximately 4% of the population. Strabismus modifies vision such that the eyes do not properly align, influencing binocular vision and depth perception.

View Article and Find Full Text PDF

Environmental exposure and effects on health of children from a tobacco-producing region.

Environ Sci Pollut Res Int

January 2017

Laboratory of Toxicology (LATOX), Department of Analyses, Faculty of Pharmacy, Federal University of Rio Grande do Sul (UFRGS), Avenida Ipiranga 2752, Santa Cecília, Porto Alegre, RS, CEP: 90610-000, Brazil.

Children may be environmentally exposed to several hazards. In order to evaluate the health of children living in a tobacco-producing region, different biomarkers of exposure and effect, as well as hematological parameters, were evaluated. Biomarkers of exposure to the following xenobiotics were assessed: pesticides, nicotine, toxic elements, and organic solvents.

View Article and Find Full Text PDF