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1.
Sensors (Basel) ; 23(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37837016

RESUMO

Electrochemical NOx sensors based on yttria-stabilized zirconia (YSZ) provide a reliable onboard way to control NOx emissions from glass-melting furnaces. The main limitation is the poisoning of this sensor by sulfur oxides (SOx) contained in the stream. To overcome this drawback, an "SO2 trap" with high SOx storage capacity and low affinity to NOx is required. Two CuO/BaO/SBA-15 traps with the same CuO loading (6.5 wt.%) and different BaO loadings (5 and 24.5 wt.%, respectively) were synthetized, thoroughly characterized and evaluated as SO2 traps. The results show that the 6.5%CuO/5%BaO/SBA-15 trap displays the highest SO2 adsorption capacity and can fully adsorb SO2 for a specific period of time, while additionally displaying a very low NO adsorption capacity. A suitable quantity of this material located upstream of the sensor could provide total protection of the NOx sensor against sulfur poisoning in glass-furnace exhausts.

2.
J Environ Sci (China) ; 99: 311-323, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33183710

RESUMO

Photochemical aging of volatile organic compounds (VOCs) in the atmosphere is an important source of secondary organic aerosol (SOA). To evaluate the formation potential of SOA at an urban site in Lyon (France), an outdoor experiment using a Potential Aerosol Mass (PAM) oxidation flow reactor (OFR) was conducted throughout entire days during January-February 2017. Diurnal variation of SOA formations and their correlation with OH radical exposure (OHexp), ambient pollutants (VOCs and particulate matters, PM), Relative Humidity (RH), and temperature were explored in this study. Ambient urban air was exposed to high concentration of OH radicals with OHexp in range of (0.2-1.2)×1012 molecule/(cm3•sec), corresponding to several days to weeks of equivalent atmospheric photochemical aging. The results informed that urban air at Lyon has high potency to contribute to SOA, and these SOA productions were favored from OH radical photochemical oxidation rather than via ozonolysis. Maximum SOA formation (36 µg/m3) was obtained at OHexp of about 7.4 × 1011molecule/(cm3•sec), equivalent to approximately 5 days of atmospheric oxidation. The correlation between SOA formation and ambient environment conditions (RH & temperature, VOCs and PM) was observed. It was the first time to estimate SOA formation potential from ambient air over a long period in urban environment of Lyon.


Assuntos
Poluentes Atmosféricos , Aerossóis/análise , Poluentes Atmosféricos/análise , França , Material Particulado , Fotoquímica
3.
Angew Chem Int Ed Engl ; 53(42): 11342-5, 2014 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-25169625

RESUMO

Yttrium-stabilized zirconia (YSZ) has been extensively studied as an electrolyte material for solid oxide fuel cells (SOFC) but its performance in heterogeneous catalysis is also the object of a growing number of publications. In both applications, oxygen activation on the YSZ surface remains the step that hinders utilization at moderate temperature. It was demonstrated by oxygen isotope exchange that a dual catalyst bed system consisting of two successive LaMnO3 and YSZ beds without intimate contact drastically enhances oxygen activation on the YSZ surface at 698 K. It can be concluded that LaMnO3 activates the triplet ground-state of molecular oxygen into a low-lying singlet state, thereby facilitating the activation of the O2 molecule on the YSZ oxygen vacancy sites. This phenomenon is shown to improve the catalytic activity of the LaMnO3-Pd/YSZ system for the partial oxidation of methane.

4.
Front Microbiol ; 12: 780201, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34925284

RESUMO

Efflux pumps contribute to multidrug resistance in Acinetobacter baumannii due to their ability to expel a wide variety of structurally unrelated compounds. This study aimed to characterize the effect of subinhibitory concentrations of clinically-relevant antibiotics and disinfectants on the promoter activity of members of the Resistance-Nodulation-Division (RND) family in A. baumannii. The promoter regions from three RND efflux pumps (AdeABC, AdeFGH and AdeIJK) and the AdeRS regulatory system from three different A. baumannii strains (ATCC 17961, ATCC 17978, and ATCC 19606) were cloned into a luciferase reporter system (pLPV1Z). Promoter activity was quantitatively assessed in both exponential and stationary phase cultures after exposure to subinhibitory concentrations of four antibiotics from different classes (rifampicin, meropenem, tigecycline and colistin) and two disinfectants (ethanol and chlorhexidine). Subinhibitory concentrations of the compounds tested had variable effects on promoter activity that were highly dependent on the A. baumannii strain, the compound tested and the growth phase. Fold changes in AdeABC promoter activity ranged from 1.97 to 113.7, in AdeFGH from -5.6 to 1.13, in AdeIJK from -2.5 to 2, and in AdeRS from -36.2 to -1.32. Taken together, these results indicate that subinhibitory concentrations of clinically-relevant antibiotics and disinfectants affect the promoter activity of RND family members in A. baumannii in a strain and growth phase dependent manner. These results may have important implications for the treatment of infections caused by A. baumannii.

5.
PLoS One ; 15(9): e0238963, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881939

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0164736.].

6.
Clin EEG Neurosci ; 51(1): 3-9, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31537100

RESUMO

Major depressive disorder (MDD) is a multidimensional disorder that is characterized by the presence of alterations in mood, cognitive capacity, sensorimotor, and homeostatic functions. Given that about half of the patients diagnosed with MDD do not respond to the various current treatments, new techniques are being sought to predict not only the course of the disease but also the characteristics that differentiate responders from non-responders. Using the electroencephalogram, a noninvasive and inexpensive tool, most studies have proposed that patients with MDD have some lateralization in brain electrical activity, with alterations in alpha and theta rhythms being observed, which would be related to dysfunctions in emotional capacity such as the absence or presence of responses to the different existing treatments. These alterations help in the identification of subjects at high risk of suffering from depression, in the differentiation into responders and nonresponders to various therapies (pharmacological, electroconvulsive therapy, and so on), as well as to establish in which period of the disease the treatment will be more effective. Although the data are still inconclusive and more research is needed, these alpha and theta neurophysiological markers could support future clinical practice when it comes to establishing an early diagnosis and treating state disorders more successfully and accurately of mood disorders.


Assuntos
Ondas Encefálicas/fisiologia , Depressão/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Ritmo Teta/fisiologia , Afeto/fisiologia , Animais , Biomarcadores/análise , Humanos
7.
PLoS One ; 11(10): e0164736, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27749904

RESUMO

BACKGROUND: The increase in immigration in Barcelona between 2000 and 2008 forced a reorganization of the control of tuberculosis (TB). TB clinical units (TBCU) were created and community health workers (CHW) were gradually included. OBJECTIVE: To understand trends in the incidence of TB among immigrants, their main characteristics and treatment compliance during the period 1991-2013. DESIGN: We conducted a cross-sectional population-based study of cases detected among immigrants by the Tuberculosis Program in Barcelona, Spain. Sociodemographic, clinical characteristics and risk factors were described. The annual incidence was calculated for various periods and geographical areas of origin. In the linear trend analysis, a p-value of <0.05 was considered statistically significant. RESULTS: We detected 3,284 cases. Incidence decreased from 144.8/100,000 inhabitants in 1991 to 53.4/100,000 in 2013. Individuals born in Pakistan-India-Bangladesh had the highest average annual incidence (675/100,000). In all, 2,156 cases (65.7%) were male. 2,272 (69.2%) had pulmonary TB, of which 48.2% were smear-positive. 33% of the cases (1,093) lived in the inner city. Contact tracing (CT) coverage in smear-positive individuals rose from 56.8% in 1991-1999 to 81.4% in 2000-2013 (p<0.01); this value was less than 50% in people from Africa and Eastern European countries. The case fatality rate was 3.6% overall and 9.8% among those born in high-income countries (p<0.01). The highest rate of treatment default (12.8%) was observed among cases from the Maghreb. The rate of successful treatment increased from 69.9% in 1991-1999 to 87.5% in 2000-2013 (p<0.01). CONCLUSION: The incidence of TB in immigrants is decreasing in Barcelona. Organizational actions, such as incorporating CHWs and TBCUs, have been decisive for the observed improvements.


Assuntos
Emigração e Imigração , Tuberculose/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Cidades , Estudos Transversais , Demografia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Espanha/epidemiologia , Taxa de Sobrevida , Tuberculose/mortalidade , Adulto Jovem
8.
J Colloid Interface Sci ; 431: 105-11, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24996018

RESUMO

Gold-containing poly(urea-formaldehyde) microparticles were prepared by the in situ polymerization method using a series of stabilization agents with different chemical nature. The effects of cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA) and tetrakis(hydroxymethyl)phosphonium chloride (THPC) on the morphology, the particle size of encapsulated gold, the gold particle size distribution and the encapsulation efficiency were investigated by using scanning electron microscopy, X-ray diffraction and atomic absorption analyses. The chemical nature of stabilizer had a marked influence on both the encapsulated gold particle size and the encapsulation efficiency. Both gold particle size and gold encapsulation efficiency increased when decreasing the stabilizer polarity number. All the microparticles here prepared were tested in the liquid phase selective oxidation of glycerol. The glycerol conversion increased and the glyceric acid selectivity decreased when decreasing gold particle sizes. Results showed that use of stabilizers with hydrophobic surfaces enhanced the selectivity to C3 products in the resulting catalysts. On the other hand, the use of stabilizers with hydrophilic surfaces increased the C-C bond cleavage products in the resulting catalysts.


Assuntos
Glicerol/química , Ouro/química , Nanopartículas Metálicas/química , Catálise , Oxirredução , Tamanho da Partícula
10.
Psicothema ; 24(4): 573-80, 2012 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-23079354

RESUMO

The goal of the present study is to analyze the influence of training in initiation to learning reading. Participants in the study were 144 preschool children from four public schools of Galicia, from a rural area of the Region of Paradanta. Out of the total sample, 72 were assigned to the experimental groups and 72 to the control groups. The design was pretest-posttest with randomized participants. Reading skills were measured with the Visual Recognition and Grapheme-Phoneme Conversion Test (TECOL).The data was analyzed with repeated measures analysis of variance. Training significantly increased the reading skill scores of the experimental groups, compared to the control groups. The program has shown a triple interaction between Measure Training × Level School. This means that there was significant variation in mean scores of reading skills as a result of training and according to the different school levels. It is concluded that the basic reading skill to develop in early childhood education is the identification and naming of letters.


Assuntos
Aprendizagem , Leitura , Ensino , Pré-Escolar , Humanos , Ensino/métodos
11.
J Vis Exp ; (45)2010 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-22158024

RESUMO

Counting cells is often a necessary but tedious step for in vitro cell culture. Consistent cell concentrations ensure experimental reproducibility and accuracy. Cell counts are important for monitoring cell health and proliferation rate, assessing immortalization or transformation, seeding cells for subsequent experiments, transfection or infection, and preparing for cell-based assays. It is important that cell counts be accurate, consistent, and fast, particularly for quantitative measurements of cellular responses. Despite this need for speed and accuracy in cell counting, 71% of 400 researchers surveyed(1) who count cells using a hemocytometer. While hemocytometry is inexpensive, it is laborious and subject to user bias and misuse, which results in inaccurate counts. Hemocytometers are made of special optical glass on which cell suspensions are loaded in specified volumes and counted under a microscope. Sources of errors in hemocytometry include: uneven cell distribution in the sample, too many or too few cells in the sample, subjective decisions as to whether a given cell falls within the defined counting area, contamination of the hemocytometer, user-to-user variation, and variation of hemocytometer filling rate(2). To alleviate the tedium associated with manual counting, 29% of researchers count cells using automated cell counting devices; these include vision-based counters, systems that detect cells using the Coulter principle, or flow cytometry(1). For most researchers, the main barrier to using an automated system is the price associated with these large benchtop instruments(1). The Scepter cell counter is an automated handheld device that offers the automation and accuracy of Coulter counting at a relatively low cost. The system employs the Coulter principle of impedance-based particle detection(3) in a miniaturized format using a combination of analog and digital hardware for sensing, signal processing, data storage, and graphical display. The disposable tip is engineered with a microfabricated, cell- sensing zone that enables discrimination by cell size and cell volume at sub-micron and sub-picoliter resolution. Enhanced with precision liquid-handling channels and electronics, the Scepter cell counter reports cell population statistics graphically displayed as a histogram.


Assuntos
Contagem de Células/instrumentação , Animais , Células COS , Contagem de Células/economia , Contagem de Células/métodos , Linhagem Celular Tumoral , Chlorocebus aethiops , Células HEK293 , Células HeLa , Humanos
12.
Methods Cell Biol ; 86: 29-57, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18442643

RESUMO

As the field of embryonic stem cell culture and differentiation advances, many diverse culturing techniques will ultimately be necessary in order to fully reproduce the various environments these cells normally encounter during development. Although most of the work to date has been performed on solid plastic supports, this growth support has several limitations in its representation of the in vivo environment. Impermeable substrates force the cells to exchange their gas and nutrients exclusively through the top side of the cultured cells. In contrast, cells growing in vivo are exposed from several directions to factors from the blood, other cells, soluble factors, and liquid-air interfaces. Additionally, solid plastic presents a smooth two-dimensional surface that is not experienced in vivo. Therefore, the use of traditional plastic presents limitations upon normal cellular morphology, function, and differentiation. An important alternative to growth on solid plastic is the growth of cells on microporous membranes. One of the many advantages to cell growth on porous membrane substrates is their ability to provide a surface that better mimics a three-dimensional in vivo setting. A porous membrane allows multidirectional exposure to nutrients and waste products. In addition, the membrane separation of dual chambers allows for the coculture of cells of different origin to study how cells interact through indirect signaling or through providing a conditioned niche for the proper growth and differentiation of cell types.


Assuntos
Técnicas de Cultura de Células/instrumentação , Diferenciação Celular , Células-Tronco Embrionárias , Matriz Extracelular , Células-Tronco Pluripotentes , Animais , Técnicas de Cultura de Células/métodos , Células Cultivadas , Técnicas de Cocultura , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/fisiologia , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Humanos , Membranas Artificiais , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/fisiologia , Porosidade , Propriedades de Superfície
13.
Reumatol Clin ; 4(4): 155-8, 2008 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-21794522

RESUMO

Streptococcus agalactiae (S agalactiae) is a germ habitually associated with infections in neonates and women during the pregnancy and the immediate puerperiumum. S. agalactiae has also been related with bacteriemias, endocarditis and bone, joint, skin and soft tissues infections in adults with concomitant diseases and even in immunocompetent patients. In the last years more than 70 cases of septic arthritis in adults due to this germ have been communicated. We present two cases of axial and peripheral joint infection due to S. agalactiae, comparing finds, treatment and evolution with the cases published until April, 2008.

14.
J Am Coll Nutr ; 24(5): 361-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16192261

RESUMO

BACKGROUND: Dietary supplementation with Virgin olive oil is considered cardioprotective. Decreasing LDL and apolipoprotein (apo) AII-lipoproteins is also appropriate for CHD protection and treatment. AIM: To study the effects of an 8%En dietary exchange of linoleic acid for oleic acid on serum and lipoprotein levels and serum and LDL-TBARS in postmenopausal women consuming a diet rich in fat (46%En; saturated/monounsaturated/polyunsaturated profile: 1.1/1.9/1). EXPERIMENTAL DESIGN: 14 postmenopausal women (63 +/- 11 years) were assigned to exchange during 28-day dietary period the culinary oil used for years consisting in a blend of olive oil plus sunflower oil (SO) for extra virgin olive oil (EVOO). SO and EVOO represented 62% of the total lipid intake. DETERMINATIONS: Dietary intakes, serum Lp(a), and cholesterol, triglycerides, phospholipids, protein, apolipoproteins AI, AII, B were determined in serum and lipoproteins. RESULTS: The dietary intervention decreased serum total cholesterol (TC), phospholipids, apo AII (all, p < 0.001) and apo B (p < 0.01). Except for triglycerides, all components of the LDL fraction decreased (at least, p < 0.05). HDL-cholesterol was not affected but HDL-phospholipids and HDL-lipids decreased (at least, p < 0.01). VLDL-apo B and VLDL-proteins decreased (all, p < 0.001). Serum Lp(a), TBARS and LDL-TBARS were not affected by the dietary exchange. The estimate of 10-year cardiovascular risk decreased (p < 0.05). Apo AII (p = 0.061) and LDL-cholesterol (p < 0.05) underwent greater modifications in normocholesterolemics, while LDL-phospholipids (p = 0.094), experienced greater alterations in hypercholesterolemics. No significant interaction was observed between dietary exchange and age (> or <65 yrs). CONCLUSIONS: These findings suggest that the dietary exchange of an olive oil and sunflower oil blend for extra virgin olive decreases LDL and apo AII levels, and the estimate of 10-year cardiovascular risk.


Assuntos
Apolipoproteína A-II/sangue , Doenças Cardiovasculares/prevenção & controle , LDL-Colesterol/sangue , Óleos de Plantas/farmacologia , Pós-Menopausa/sangue , Apolipoproteínas B/sangue , Doenças Cardiovasculares/sangue , Colesterol/sangue , HDL-Colesterol/sangue , VLDL-Colesterol/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Azeite de Oliva , Óleos de Plantas/administração & dosagem , Pós-Menopausa/fisiologia , Fatores de Risco , Óleo de Girassol , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Triglicerídeos/sangue
15.
J Nutr ; 132(1): 50-4, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11773507

RESUMO

Increased HDL-cholesterol levels have been associated with lower coronary heart disease (CHD) risk. However, HDL are heterogeneous lipoproteins, and particles enriched in apolipoprotein (Apo) AII have been associated with increased CHD risk. We examined the effect of dietary intervention on HDL composition in 14 postmenopausal women subjected to two consecutive diet periods, i.e., an oleic acid sunflower oil diet followed by a palmolein diet, each lasting 4 wk. The linoleic acid was kept at 4% total energy and the cholesterol intake at 400 mg/d. The palmolein diet increased serum total cholesterol (TC) (P < 0.001), phospholipids (P < 0.001), Apo AII (P < 0.001), HDL cholesterol (P < 0.05), HDL lipids (P < 0.05), HDL proteins (P < 0.01) and the HDL total mass (P < 0.05). The HDL cholesterol/Apo AI ratio was increased 22.0% (P < 0.05), whereas the HDL cholesterol/Apo AII and the Apo AI/Apo AII ratios were decreased 19.4% (P < 0.01) and 30.4%, (P < 0.001), respectively. When the effects of the dietary intervention were examined according to the cholesterolemia status (< or >6.2 mmol/L), the most significant changes (P < 0.001) were related to Apo AII levels. Moreover, a significant dietary oil by cholesterol level interaction was found for Apo AII and the HDL cholesterol/Apo AII ratio. In summary, a palmolein diet increased TC and HDL cholesterol compared with oleic acid sunflower oil diet; however, the increase in Apo AII but not in Apo AI suggests the impairment of reverse cholesterol transport and potentially an increase in CHD risk. This effect was more marked in women with serum TC > 6.2 mmol/L.


Assuntos
Apolipoproteína A-II/sangue , Doença das Coronárias/etiologia , Gorduras na Dieta/administração & dosagem , Lipoproteínas HDL/química , Pós-Menopausa/sangue , Idoso , Apolipoproteína A-I/sangue , Doença das Coronárias/sangue , Gorduras na Dieta/sangue , Ácidos Graxos/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Avaliação Nutricional , Óleo de Palmeira , Óleos de Plantas/administração & dosagem , Óleos de Plantas/química , Fatores de Risco , Óleo de Girassol
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