The mechanism behind Pd(II) and carbofuran-induced change of graphene quantum dots photoluminescence intensity

The increasing presence of pesticides and heavy metals in the environment and their negative impact on human, animal, and plant health, demand green, low-cost, and simple methods for their monitoring. Due to photoluminescence (PL) in the visible part of the spectrum, biocompatibility, and ecological acceptability, graphene quantum dots (GQDs) are at the center of attention in the field of optical sensing. GQDs show great potential as PL sensors for Pd(II) ions and insecticide carbofuran. In this work, FTIR spectroscopy and Density Functional Theory (DFT) calculation were used to resolve the mechanism of PL change in the presence of these analytes

Atención en un centro de parto según las recomendaciones de la Organización Mundial de la Salud

Centros de parto constituem modelo que\ud adota tecnologia apropriada na assistência\ud à parturiente. O objetivo foi caracterizar\ud a assistência intraparto em um centro de\ud parto extra-hospitalar quanto às práticas\ud recomendadas pela Organização Mundial\ud da Saúde (OMS). Estudo descritivo sobre\ud 1.079 partos assistidos de 2006 a 2009 na\ud Casa do Parto de Sapopemba, São Paulo,\ud Brasil. Os resultados mostraram ausculta\ud intermitente (média=7 controles); posição\ud materna no expulsivo semissentada\ud (82,3%), lateral (16,0%), outras (1,7%);\ud aceitação da dieta (95,6%); acompanhante\ud (93,3%); até três exames vaginais (85,4%);\ud banho de aspersão (84,0%), deambulação\ud (68,0%), massagem (60,1%), exercícios\ud com bola suíça (51,7%); amniotomia\ud (53,4%); ocitocina na dilatação (31,0%),\ud banho de imersão (29,3%), ocitocina no\ud expulsivo (25,8%) e episiotomia (14,1%).\ud Concluiu-se que os profissionais do centro\ud de parto utilizam práticas recomendadas\ud pela OMS, contudo existem práticas cujo\ud uso pode ser reduzido, tais como amniotomia,\ud administração de ocitocina, episiotomia\ud e posição semissentada no expulsivoBirth centers are maternal care models\ud that use appropriate technology when\ud providing care to birthing women. This\ud descriptive study aimed to characterize intrapartum\ud care in a freestanding birth center,\ud in light of the practices recommended\ud by the World Health Organization (WHO),\ud with 1,079 assisted births from 2006 to\ud 2009 in the Sapopemba Birth Center, São\ud Paulo, Brazil. Results included the use of\ud intermittent auscultation (mean=7 controls);\ud maternal positions during delivery:\ud semi-sitting (82.3%), side-lying (16.0%),\ud other positions (1.7%), oral intake (95.6%);\ud companionship (93.3%); exposure to up\ud to three vaginal examinations (85.4%),\ud shower bathing (84.0%), walking (68.0%),\ud massage (60.1%), exercising with a Swiss\ud ball (51.7%); amniotomy (53.4%), oxytocin\ud use during the first (31.0%) and second\ud stages of labor (25.8%), bath immersion\ud (29.3%) and episiotomy (14.1%). In this\ud birth center, care providers used practices\ud recommended by the WHO, although\ud some practices might have been applied\ud less frequentlyCentros de parto constituyen un modelo\ud que adopta la tecnología apropiada en la\ud atención a la parturienta. El objetivo fue caracterizar\ud la atención intraparto en un centro\ud de parto extra-hospitalario en relación a las\ud prácticas recomendadas por la Organización\ud Mundial de la Salud (OMS). Estudio descriptivo\ud sobre 1.079 partos atendidos del 2006 al\ud 2009 en la Casa de Parto de Sapopemba, São\ud Paulo, Brasil. Los resultados mostraron: auscultación\ud intermitente (media=7 controles);\ud posición materna en el expulsivo - semisentada\ud (82,3%), lateral (16,0%), otras (1,7%);\ud aceptación de dieta (95,6%); acompañante\ud (93,3%); hasta tres exámenes vaginales\ud (85,4%); baño en ducha (84,0%), deambulación\ud (68,0%), masaje (60,1%), ejercicios con\ud pelota suiza (51,7%); amniotomía (53,4%);\ud oxitocina durante la dilatación (31,0%), baño\ud de inmersión (29,3%), oxitocina durante el\ud expulsivo (25,8%) y episiotomía (14,1%). Se\ud concluyó que los profesionales del centro de\ud parto utilizan prácticas recomendadas por\ud la OMS, pero existen algunas prácticas cuyo\ud uso puede reducirse, tales como la amniotomía,\ud administración de oxitocina, episiotomía\ud y posición semisentada en el período\ud expulsivoCNPqPIBIC 115521/2008-

The antitumor immune response in HER-2 positive, metastatic breast cancer patients

The aim of this study was to determine the basis for anti-tumor immune reactivity observed in patients with human epidermal growth factor receptor-2 (HER-2) (3+) breast carcinoma using an in vitro model in which the role of the HER-2-specific monoclonal antibody Herceptin was also investigated. Patients with metastatic breast cancer who had their primary tumor resected were included in this study. Peripheral blood mononuclear cell (PBMC)-dependent cytotoxicity in the presence or absence of Herceptin were assessed using the survival of target breast adenocarcinoma MDA-MB-361 cells as a parameter in a (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) test. We observed a significant increase in PBMC-dependent cytotoxicity when autologous serum was introduced in the assay. Furthermore, the addition of Herceptin significantly increases their cytotoxicity. These data suggest that autologous serum constitutively contains factors that might affect PBMC-dependent cytotoxic activity against HER-2 positive cancer cells

Gamma-ray-induced structural transformation of GQDs towards the improvement of their optical properties, monitoring of selected toxic compounds, and photo-induced effect on bacterial strains

Structural modification of different carbon-based nanomaterials is often necessary to improve their morphology and optical properties, particularly the incorporation of N-atoms in graphene quantum dots (GQDs). Here, a clean, simple, one-step, and eco-friendly method for N-doping of GQDs using gamma irradiation is reported. GQDs were irradiated in the presence of the different ethylenediamine (EDA) amounts (1 g, 5 g, and 10 g) and the highest % of N was detected in the presence of 10 g. N-doped GQDs emitted strong, blue photoluminescence (PL). Photoluminescence quantum yield was increased from 1.45, as obtained for non-irradiated dots, to 7.24% for those irradiated in the presence of 1 g of EDA. Modified GQDs were investigated as a PL probe for the detection of insecticide Carbofuran (2,2-Dimethyl-2,3-dihydro-1-benzofuran-7- yl methylcarbamate) and herbicide Amitrole (3-amino-1,2,4-triazole). The limit of detection was 5.4 µmol L−1 for Carbofuran. For the first time, Amitrole was detected by GQDs in a turn-off/turn-on mechanism using Pd(II) ions as a quenching agent. First, Pd(II) ions were quenched (turn-off) PL of GQDs, while after Amitrole addition, PL was recovered linearly with Amitrole concentration (turn-on). LOD was 2.03 µmol L−1 . These results suggest that modified GQDs can be used as an efficient new material for Carbofuran and Amitrole detection. Furthermore, the phototoxicity of dots was investigated on both Gram-positive and Gram-negative bacterial strains. When bacterial cells were exposed to different GQD concentrations and illuminated with light of 470 nm wavelength, the toxic effects were not observed

A qualitative study of the use of netspeak in English language classroom : implementation of netspeak in high school and university language teaching

The aim of this research is to explore the presence and pedagogical implications of Netspeak in English language classroom. Netspeak is the type of language that evolves within the electronic environment, and it is classified as an informal language. The goal of this research is to examine how Netspeak is accepted by high school and university English language teachers from Finland and Serbia, and whether and how they implement Netspeak in their teaching. The topic of the educational use of Netspeak has not yet been widely explored, and, therefore, there are not many researches done on this matter. In this regard, researching the use of Netspeak for teaching purposes is a relatively new field, and this MA thesis brings new results on the subject and paves the way for further researches. It is a multidisciplinary research which combines linguistic research with media education. The data are collected through 18 interviews of the English teachers working in high schools and universities in Finland and Serbia, and through the review of 3 segments of written teaching materials in which the use of Netspeak is present. The method used in this qualitative study is inductive qualitative content analysis (IQCA). The findings show that the pedagogical potential of Netspeak is noticed by the teachers. The theory which comes out of the overall result of the research is that the majority of English language teachers implement Netspeak in their teaching. The approaches in the use of Netspeak are presented in the thesis

Beneficial effects of ceftriaxone against pentylenetetrazole-evoked convulsions.: Exp.Biology and Medicine

NRC publication: Ye

Nutrition and Health Claims Spectra of Pre-Packaged Foods on Serbian Supermarket Shelves: A Repeated Cross-Sectional Study

Nutrition and health claims (NHCs) are a powerful tool that influence consumers' final decision on the choice of food products. The purposes of this repeated cross-sectional study were to (i) assess the prevalence of pre-packaged food products containing nutrition and health claims among different food categories, (ii) to determine the type of NHCs labelled on the examined food products, and (iii) to evaluate the trend in the use of NHCs in comparison to the 2012 survey. The survey was conducted immediately before the full enforcement of the new national legislation on NHCs in 2020. It comprised 3141 pre-packaged food products from 10 product categories. In total, 21.2% of food products contained any claim (19.4% contained any nutrition claim; 8.2% contained any health claim). In comparison to the 2012 survey, we observed a rising trend in the presence of NHCs; the use of nutrition claims on food products increased three times and the use of health claims increased 1.3 times in the 2020 survey. Bearing in mind that NHCs are a powerful tool guiding consumers' food purchase decisions, NHCs should be supported by precise legislation and strict surveillance by the public health authorities

Antioxidative and Photo-Induced Effects of Different Types of N-Doped Graphene Quantum Dots

Due to the increasing number of bacterial infections and the development of resistivity toward antibiotics, new materials and approaches for treatments must be urgently developed. The production of new materials should be ecologically friendly considering overall pollution with chemicals and economically acceptable and accessible to the wide population. Thus, the possibility of using biocompatible graphene quantum dots (GQDs) as an agent in photodynamic therapy was studied. First, dots were obtained using electrochemical cutting of graphite. In only one synthetic step using gamma irradiation, GQDs were doped with N atoms without any reagent. Obtained dots showed blue photoluminescence, with a diameter of 19–89 nm and optical band gap of 3.23–4.73 eV, featuring oxygen-containing, amino, and amide functional groups. Dots showed antioxidative activity; they quenched •OH at a concentration of 10 μg·mL−1, scavenged DPPH• radicals even at 5 μg·mL−1, and caused discoloration of KMnO4 at 30 μg·mL−1. Under light irradiation, dots were able to produce singlet oxygen, which remained stable for 10 min. Photoinduced effects by GQDs were studied on several bacterial strains (Listeria monocytogenes, Bacillus cereus, clinical strains of Streptococcus mutans, S. pyogenes, and S. sangunis, Pseudomonas aeruginosa, and one yeast strain Candida albicans) but antibacterial effects were not noticed

Raman study of the interactions between highly ordered pyrolytic graphite (HOPG) and polyoxometalates: The effects of acid concentration

Heteropoly acids (HPAs) have found wide applications, such as in catalysis, energy conversion and storage, analytical chemistry, clinical medicine, materials science and others, but their use is limited due to their low surface area and high solubility in water. One of the possible ways to overcome these obstacles is to use height specific surface area supports for HPAs, such as carbon nanomaterials. Raman spectroscopy was applied for a studying the interaction between HPAs and highly ordered pyrolytic graphite (HOPG) as a model of a support. HOPG was exposed to two different HPAs: 12-tungsto-phosphoric acid and 12-molybodphosphoric acid, at different concentrations. It was noticed that 12-molybodphosphoric acid had stronger effects on the HOPG structure causing a weak doping and an increase of structural disorder. It was supposed that HOPG interacts with especially external oxygen atoms of 12-molybodphosphoric acid. Atomic force microscopy showed that the surface roughness of HOPG treated with 12-molybodphosphoric acid increases with increasing acid concentration, while in the case of HOPG exposed to 12-tungsto-phosphoric acid, the surface roughness concentration independent. The growth trend in the measured surface roughness (RMS) was in the agreement with the changes in the intensity ratio I-D/I-G obtained from the Raman spectra of the HOPG samples treated with 12-molybdophosphoric acid