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1.
Trop Biomed ; 39(4): 575-578, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36602218

RESUMO

Malaria and dengue fever are among the most common mosquito-borne diseases worldwide; however, reports of coinfection are rare. We present a case of severe malaria and dengue coinfection in a 16-yearold female patient presenting with fever, thrombocytopenia, pleural effusion, myopericarditis, and acute respiratory distress syndrome. Dengue infection was confirmed by the presence of immunoglobin M antibodies and nonstructural protein 1, while malaria was confirmed by the presence of Plasmodium vivax in thick and thin blood smears. This is the first report of a dengue/malaria coinfection in Mexico.


Assuntos
Coinfecção , Doenças Transmissíveis , Vírus da Dengue , Dengue , Malária Vivax , Malária , Animais , Humanos , Feminino , Adolescente , Plasmodium vivax , Coinfecção/diagnóstico , México , Dengue/complicações , Dengue/diagnóstico , Malária Vivax/complicações , Malária Vivax/diagnóstico
2.
Sci Rep ; 11(1): 12027, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103560

RESUMO

We report on the delithiation of LiCoO2 thin films using oxalic acid (C2H2O4) with the goal of understanding the structural degradation of an insertion oxide associated with Li chemical extraction. Using a multi-technique approach that includes synchrotron radiation X-ray diffraction, scanning electron microscopy, micro Raman spectroscopy, photoelectron spectroscopy and conductive atomic force microscopy we reveal the balance between selective Li extraction and structural damage. We identify three different delithiation regimes, related to surface processes, bulk delithiation and damage generation. We find that only a fraction of the grains is affected by the delithiation process, which may create local inhomogeneities. However, the bulk delithiation regime is effective to delithiate the LCO film. All experimental evidence collected indicates that the delithiation process in this regime mimics the behavior of LCO upon electrochemical delithiation. We discard the formation of Co oxalate during the chemical extraction process. In conclusion, the chemical route to Li extraction provides additional opportunities to investigate delithiation while avoiding the complications associated with electrolyte breakdown and simplifying in-situ measurements.

3.
Med Vet Entomol ; 35(4): 652-657, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34173246

RESUMO

The deer ked Lipoptena mazamae (Diptera: Hippoboscidae) (Róndani), is a blood-feeding obligate ectoparasite of several species of deer and brocket. However, at present little information is available about its role as a vector of hemoparasites. Nonetheless, it is considered a competent vector for the transmission of Bartonella species. The aim of this study was performing the morphological and molecular identification of ked flies and to carry out the detection of Bartonella. We collected specimens from Chiná, Campeche, Mexico associated with white-tailed deer. Using polymerase chain reaction (PCR), of COI, gltA and rpoB genes, we were able to obtain the first barcode for L. mazamae from Mexico and identified a new species of Bartonella which was found with a prevalence of 73%. The data obtained in this study confirmed the presence of L. mazamae associated with white-tailed deer and its possible role as vector of Candidatus Bartonella odocoilei n. sp. in Mexico and we considered that it may also be present in white-tailed deer populations in the U.S.A. Additional investigations into Bartonella species associated with deer ked could provide further insight into their pathogenicity and its role as a zoonotic agent.


Assuntos
Bartonella , Cervos , Dípteros , Animais , Bartonella/genética , Cervos/parasitologia , México/epidemiologia
4.
Food Sci Technol Int ; 26(6): 493-502, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32070143

RESUMO

The demand for sustainable and healthy food is increasing. Therefore, it is necessary to find new sources of functional ingredients for design of novel food products. Microalgae are reliable sources of functional ingredients, ready for exploitation with purpose of production of human food. This work explores consumers' acceptance of novel foods based on microalgae. To achieve natural and realistic eating location, sensory analysis was conducted in a real restaurant in Universitat Politècnica de València. A check-all-that-apply questionnaire and hedonic scale registered the consumers' expectations (N = 85), perceptions and acceptance, before and after taste of typical Valencian breadsticks. Food neophobia can affect acceptability of novel foods, thus, participants completed a test designed to measure their attitudes towards new food. Microalgae breadsticks have distinctive characteristics compared to control breadsticks, such as colour, flavour and odour, because of microalgae presence. Still, those breadsticks were as acceptable as the control breadsticks according to the consumer preferences. Consumers expected more differences amongst both breadsticks before tasting, but they lowered the differences in perception after trying them. Consumers consider that the product is healthier, and they would understand if it had greater expense. We believe this information can be useful for selling / marketing this novel product.


Assuntos
Comportamento do Consumidor , Manipulação de Alimentos , Percepção Gustatória , Adulto , Idoso , Transtorno Alimentar Restritivo Evitativo , Comportamento de Escolha , Cor , Feminino , Preferências Alimentares , Humanos , Masculino , Microalgas , Pessoa de Meia-Idade , Odorantes , Paladar
5.
Sci Rep ; 9(1): 11514, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395922

RESUMO

The second order nonlinear optical response of gold nanoprisms arrays is investigated by means of second harmonic generation (SHG) experiments and simulations. The polarization dependence of the nonlinear response exhibits a 6-fold symmetry, attributed to the local field enhancement through the excitation of the surface plasmon resonances in bow-tie nanoantennas forming the arrays. Experiments show that for polarization of the input light producing excitation of the plasmonic resonances in the bow-tie nanoantennas, the SHG signal is enhanced; this despite the fact that the linear absorption spectrum is not dependent on polarization. The results are confirmed by electrodynamic simulations which demonstrate that SHG is also determined by the local field distribution in the nanoarrays. Moreover, the maximum of SHG intensity is observed at slightly off-resonance excitation, as implemented in the experiments, showing a close relation between the polarization dependence and the structure of the material, additionally revealing the importance of the presence of non-normal electric field components as under focused beam and oblique illumination.

6.
J Phys Chem B ; 122(2): 745-756, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-28885023

RESUMO

We report a surface X-ray diffraction study of the crystalline structure changes and critical behavior across the (3√2 × âˆš2)R45° → (√2 × âˆš2)R45° surface phase transition at 360 K for 0.5 monolayers of Sn on Cu(100). The phase transition is of the order-disorder type and is due to the disordering of the Cu atomic vacancies present in the low temperature phase. Two different atomic sites for Sn atoms, characterized by two different heights, are maintained across the surface phase transition.

7.
Nanotechnology ; 26(44): 444001, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26469205

RESUMO

Plasmonic crystals, which consist of periodic arrangements of surface features at a metal-dielectric interface, allow the manipulation of optical information in the form of surface plasmon polaritons. Here we investigate the excitation and propagation of plasmonic beams in and around finite size plasmonic crystals at telecom wavelengths, highlighting the effects of the crystal boundary shape and illumination conditions. Significant differences in broad plasmonic beam generation by crystals of different shapes are demonstrated, while for narrow beams, the propagation from a crystal onto the smooth metal film is less sensitive to the crystal boundary shape. We show that by controlling the boundary shape, the size and the excitation beam parameters, directional control of propagating plasmonic modes and their behaviour such as angular beam splitting, focusing power and beam width can be efficiently achieved. This provides a promising route for robust and alignment-independent integration of plasmonic crystals with optical communication components.

8.
J Food Sci ; 80(8): E1725-34, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26130376

RESUMO

In this paper, physico-chemical and structural properties of cut and cooked purple-flesh potato, green bean pods, and carrots have been studied. Three different cooking methods have been applied: traditional cooking (boiling water at 100 °C), cook-vide (at 80 and 90 °C) and sous-vide (at 80 °C and 90 °C). Similar firmness was obtained in potato applying the same cooking time using traditional cooking (100 °C), and cook-vide and sous-vide at 90 °C, while in green beans and carrots the application of the sous-vide (90 °C) required longer cooking times than cook-vide (90 °C) and traditional cooking (100 °C). Losses in anthocyanins (for purple-flesh potatoes) and ascorbic acid (for green beans) were higher applying traditional cooking. ß-Carotene extraction increased in carrots with traditional cooking and cook-vide (P < 0.05). Cryo-SEM micrographs suggested higher swelling pressure of starch in potatoes cells cooked in contact with water, such as traditional cooking and cook-vide. Traditional cooking was the most aggressive treatment in green beans because the secondary walls were reduced compared with sous-vide and cook-vide. Sous-vide preserved organelles in the carrot cells, which could explain the lower extraction of ß-carotene compared with cook-vide and traditional cooking. Sous-vide cooking of purple-flesh potato is recommended to maintain its high anthocyanin content. Traditional boiling could be recommended for carrots because increase ß-carotenes availability. For green beans, cook-vide, and sous-vide provided products with higher ascorbic acid content.


Assuntos
Antocianinas/análise , Antioxidantes/análise , Ácido Ascórbico/análise , Culinária/métodos , Temperatura Alta , Verduras/química , beta Caroteno/análise , Daucus carota/química , Fabaceae/química , Humanos , Solanum tuberosum/química , Amido/química , Água
9.
Sci Rep ; 4: 7234, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25429786

RESUMO

Plasmonic crystals provide many passive and active optical functionalities, including enhanced sensing, optical nonlinearities, light extraction from LEDs and coupling to and from subwavelength waveguides. Here we study, both experimentally and numerically, the coherent control of SPP beam excitation in finite size plasmonic crystals under focussed illumination. The correct combination of the illuminating spot size, its position relative to the plasmonic crystal, wavelength and polarisation enables the efficient shaping and directionality of SPP beam launching. We show that under strongly focussed illumination, the illuminated part of the crystal acts as an antenna, launching surface plasmon waves which are subsequently filtered by the surrounding periodic lattice. Changing the illumination conditions provides rich opportunities to engineer the SPP emission pattern. This offers an alternative technique to actively modulate and control plasmonic signals, either via micro- and nano-electromechanical switches or with electro- and all-optical beam steering which have direct implications for the development of new integrated nanophotonic devices, such as plasmonic couplers and switches and on-chip signal demultiplexing. This approach can be generalised to all kinds of surface waves, either for the coupling and discrimination of light in planar dielectric waveguides or the generation and control of non-diffractive SPP beams.

10.
Eur Phys J E Soft Matter ; 37(7): 22, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25080174

RESUMO

A slab of nematic-side-chain-liquid-single-crystal elastomer (NSCLSCE), with the director initially oriented in the z -direction, is subjected to a pair of equal mechanical loads and electrical force fields in the x , y directions. The electric fields tend to make easier the rotation of the director after the application of the mechanical force field. A nonlinear expression for the free energy density is used to obtain the interval of stretching for which the system becomes unstable. However, the elastic energy of the network is assumed to be linear. The stress-strain curves predicted by the model show an unstable zone between two linearly increasing segments. The possibility of bifurcation phenomena has been examined.

11.
Nutr Hosp ; 26(4): 803-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22470027

RESUMO

The food frequency questionnaires are widely used in epidemiological researches like dietary assessment method. Traditionally, they have been self-administered in paper but the use of information and communication technologies has led to develop Internet and computerized food frequency questionnaires. It is the objective of this article to offer a global perspective of the new technologies applied to FFQ. It will be presented the purpose of the food frequency questionnaire, the number of strengths of the web-based surveys versus print-surveys and finally, a description of the manuscripts that have used web-based and computerized FFQ.


Assuntos
Inquéritos sobre Dietas/métodos , Inquéritos e Questionários , Computadores , Métodos Epidemiológicos , Comportamento Alimentar , Humanos , Internet
12.
Nutr Hosp ; 26(6): 1378-84, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22411386

RESUMO

OBJECTIVE: To test the reliability of dietary intake data measured with an online food frequency questionnaires (FFQ) applied to a university population by comparing the results with those from a paper and pencil version. MATERIALS AND METHODS: A total of 50 students were recruited from the second-year Food Technology course at the Universitat Politècnica de València (Comunidad Valenciana, Spain) in the academic year 2008-2009. The students were between the ages of 20-32. The participants completed both presentation modes of the FFQ (paper and pencil and online) in a cross-over study with a time interval of 3-week. To study the effect of ordering of the questionnaires, participants were randomly assigned to group A (paper and pencil FFQ first) and group B (online FFQ first). Both self-administered semi-quantitative presentations of the FFQ included 84 food items divided into six groups (dairy products; eggs, meat and fish; vegetables, legumes and fruits; bread, cereals and similar; oils, fats and sweets; beverages and pre-cooked). Participants were asked how frequently and how much each food item they had consumed in the previous year. RESULTS: The response rate was 78% (39 students, 23% men and 77% women). For the total sample, the median dietary intakes were higher for the paper and pencil FFQ than the online version for energy (2,077 vs. 1,635 kcal/day), proteins (96 vs. 88 g/day), carbohydrates (272 vs. 211 g/day), and fat (70 vs. 58 g/day), respectively. These differences were statistically significant. However, there were not significant differences between the two presentations when the consumption by groups of food was calculated, except for "beverages and pre-cooked" group. CONCLUSIONS: The pilot testing showed that this online FFQ is a useful tool for estimating the intake of food groups in this university population. On the other hand, the differences found in the results of the absolute quantities of energy and nutrients intakes were not clear. These differences could be due to the problems that the participants had for reporting portion size in the paper and pencil FFQ as photographs of portion sizes were not presented.


Assuntos
Inquéritos sobre Dietas/métodos , Inquéritos e Questionários , Adulto , Peso Corporal , Estudos Cross-Over , Interpretação Estatística de Dados , Carboidratos da Dieta , Gorduras na Dieta , Proteínas Alimentares , Ingestão de Energia , Comportamento Alimentar , Feminino , Alimentos , Preferências Alimentares , Humanos , Internet , Estilo de Vida , Masculino , Atividade Motora , Projetos Piloto , Reprodutibilidade dos Testes , Fumar , Universidades , Adulto Jovem
13.
Nutr Hosp ; 26(6): 1440-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22411394

RESUMO

OBJECTIVE: To introduce and describe a new tool called UPV-FFQ to evaluate dietary intake of the university population. The new tool consists principally in a self-administered online food frequency questionnaire (FFQ). MATERIALS AND METHODS: The tool UPV-FFQ has been developed by means of web pages applying the technology ASP.NET 2.0 and using the database SQL Server 2005 as support. To develop the FFQ has been used as model the paper and pencil FFQ called "Dieta, salud y antropometría en la población universitaria". RESULTS: The tool has three parts: (1) a homepage, (2) a general questionnaire and (3) a FFQ. The FFQ has a closed list of 84 food items commonly consumed in Valencia region. The respondents has to indicate the food items that they consume (2 possible options), the frequency of consumption (9 response options) and the quantity consumed (7 response options). The UPV-FFQ has approximately 250 color photographs that represents to three portion sizes. The photographs are useful to help the respondents to choose the portion sizes that more adjusts to their habitual portions. The new tool provides quantitative information of the habitual intake of 31 nutritional parameters and provides qualitative information of the general questionnaire. A pilot study was done for a total of 57 respondents. The media time spend to fill in was 15 minutes. CONCLUSIONS: The pilot study concluded that the questionnaire was ease-of-use, low cost and time-effectiveness questionnaire. The format and the sequence of the questions were easily understood.


Assuntos
Inquéritos sobre Dietas/métodos , Dieta , Ingestão de Alimentos , Internet , Inquéritos e Questionários , Comportamento Alimentar , Feminino , Humanos , Masculino , Projetos Piloto , Reprodutibilidade dos Testes , Espanha , Estudantes , Universidades , Adulto Jovem
14.
J Phys Condens Matter ; 21(5): 055001, 2009 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-21817288

RESUMO

We present measurements of the Fermi surface and underlying band structure of Sn/Cu(100)-[Formula: see text]. This phase is observed for a coverage of 0.60-0.65 monolayers. Its electronic structure is characterized by a free-electron-like surface band folded with the reconstruction periodicity. At variance with other surface phases of Sn on Cu(100), no temperature-induced phase transition is observed for this phase from 100 K up to the desorption of Sn.

15.
J Phys Condens Matter ; 21(13): 134011, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21817486

RESUMO

The application of genetic algorithms to the analysis of surface x-ray diffraction data is discussed and the implementation of a genetic algorithm of evolutionary type is described in detail. The structure of Sn/Cu(100)-[Formula: see text] is determined on the basis of surface x-ray diffraction data analysed using this algorithm. The results are compared to previous findings using other techniques.

16.
J Phys Condens Matter ; 21(47): 474216, 2009 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-21832495

RESUMO

We report an investigation into the surface electronic structure of Pb/Cu(100) in the submonolayer coverage range. A prominent surface band is detected in the whole coverage range analysed. The band is gradually filled as Pb coverage increases. For a Pb coverage of 0.375 ML, corresponding to the c(4 × 4) phase, a strong c(4 × 4) folding of this state is observed in the valence band. The origin of these results and the nature of the surface electronic structure of Pb/Cu(100)- c(4 × 4) are discussed.

18.
Rev. Méd. Clín. Condes ; 18(1): 15-19, ene. 2007. tab
Artigo em Espanhol | LILACS | ID: lil-473225

RESUMO

La infección articular sigue siendo un motivo relativamente frecuente de consulta, tanto en los Servicios de Urgencia como en las consultas del médico general. De ahí que el diagnóstico precoz y la derivación oportuna para el inicio de un tratamiento mixto que considera el uso adecuado de esquemas antibióticos asociado a aseo quirúrgico, son cruciales en su manejo y pronóstico -que aun no se encuentra exento de complicaciones incluso de mortalidad en algunos pacientes con enfermedades predisponentes-. En esta revisión se realiza un análisis referente al diagnóstico y tratamiento oportuno que a menudo requiere de la participación de distintos especialistas para un mejor resultado en beneficio de la funcionalidad articular y/o de una complicación de mayor riesgo para el paciente.


Assuntos
Humanos , Articulações/microbiologia , Artrite Infecciosa/diagnóstico , Artrite Infecciosa/terapia , Diagnóstico Diferencial , Staphylococcus/patogenicidade , Streptococcus/patogenicidade
19.
J Chem Phys ; 125(14): 144719, 2006 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-17042643

RESUMO

We present an analysis of the electronic structure of C60 adsorbed on a vicinal Au(111) surface at different fullerene coverages using photoemission, x-ray absorption, and scanning tunneling microscopy/spectroscopy (STS). STS provides a straightforward determination of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) levels with respect to the Fermi energy. At C60 coverages of 0.5 and 1 ML a 2.7 eV wide HOMO-LUMO gap is found. The near-edge x-ray absorption fine structure (NEXAFS) spectrum for the 0.5 ML C60 nanomesh structure displays a significant intensity at the low energy side of the LUMO exciton peak, which is explained as due to absorption into HOMO-LUMO gap states localized at individual C60 cluster edges. From 0.5 to 1 ML we observe a rigid shift of the HOMO-LUMO peaks in the STS spectra and an almost complete quenching of the gap states feature in NEXAFS.

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