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3. Do Magnetic Fields Destroy Black Hole Accretion Disk g-Modes?

Author

Ortega-Rodríguez, Manuel, Solís-Sánchez, Hugo, Arguedas-Leiva, J. Agustín, Wagoner, Robert V., and Levine, Adam

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Diskoseismology, the theoretical study of normal mode oscillations in geometrically thin, optically thick accretion disks, is a strong candidate to explain some QPOs in the power spectra of many black hole X-ray binary systems. The existence of g-modes, presumably the most robust and visible of the modes, depends on general relativistic gravitational trapping in the hottest part of the disk. As the existence of the required cavity in the presence of magnetic fields has been put into doubt by theoretical calculations, we will explore in greater generality what the inclusion of magnetic fields has to say on the existence of g-modes. We use an analytical perturbative approach on the equations of MHD to assess the impact of such effects. Our main conclusion is that there appears to be no compelling reason to discard g-modes. In particular, the inclusion of a non-zero {\it radial} component of the magnetic field enables a broader scenario for cavity non-destruction, especially taking into account recent simulations' saturation values for the magnetic field., Comment: 15 pages, 7 figures, accepted for publication in The Astrophysical Journal

Published
2015
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13. Efectos tóxicos agudos y crónicos de los hidrocarburos sobre crustáceos de las familias palaemonidae y hyalellidae: revisión sistemática.

Author

LEIVA, J. VALERIA YON, MARINA, ADAN, LAURENTE, ALESSANDRA, ROJAS PALACIOS, JIMENA RUBY, MAURTUA, KIARA, GRACIELA ÁLVAREZ, MARÍA, ZEVALLOS, PIERO, and IANNACONE, JOSÉ

Subjects
*POLYCYCLIC aromatic hydrocarbons, *AMPHIPODA, *DNA damage, *POISONS, *AQUATIC organisms
Abstract

Contamination by polycyclic aromatic hydrocarbons (PAH) in freshwater ecosystems represents a serious environmental problem. When they enter the water, either by oil spills or industrial discharges, they adhere to suspended particles, accumulating in sediments and causing them to be absorbed by aquatic organisms, such as decapods and amphipods. Therefore, to evaluate the effects of PAHs on Macrobrachium borelli and Hyalella azteca, a bibliographic compilation was made considering the axes of hydrocarbon toxicity and adaptation mechanisms for these pollutants. The results for decapods indicate a high toxicity for the water-soluble fraction with diesel, although this does not prevent normal hatching of eggs. For amphipods, it was found that, according to their mortality, it is a more sensitive species than other organisms, such as chironomids. In addition, the sublethal effects due to PAH exposure vary in the affectation in the size and behavior of the organism, as well as DNA damage. Finally, the adaptive mechanisms it possesses are not considered effective for the survival of the species. [ABSTRACT FROM AUTHOR]

Published
2024
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15. Infection-specific PET imaging with 18F-fluorodeoxysorbitol and 2-[18F]F-¿-aminobenzoic acid: An extended diagnostic tool for bacterial and fungal diseases

Author

Rua, M. (Marta), Simón-Martínez, J.A. (Jon Ander), Collantes, M. (María), Ecay, M. (Margarita), Leiva, J. (José), Carmona-Torre, F. (Francisco de A.), Ramos-Membrive, R. (Rocío), Pareja, F. (Félix), Pulagam, K.R. (Krishna R.), Llop, J. (Jordi), Pozo, J.L. (José Luis) del, and Peñuelas-Sanchez, I. (Ivan)

Subjects
18[F]FPABA, Folate, PABA para-aminobenzoic acid, 18[F]FDS, PET imaging, Sorbitol, FDG (18F-fluorodeoxyglucose)-PET, CT, Mouse model
Abstract

Introduction Suspected infectious diseases located in difficult-to-access sites can be challenging due to the need for invasive procedures to isolate the etiological agent. Positron emission tomography (PET) is a non-invasive imaging technology that can help locate the infection site. The most widely used radiotracer for PET imaging (2-deoxy-2[F-18] fluoro-D-glucose: [F-18]FDG) shows uptake in both infected and sterile inflammation. Therefore, there is a need to develop new radiotracers able to specifically detect microorganisms. MethodsWe tested two specific radiotracers: 2-deoxy-2-[F-18]-fluoro-D-sorbitol ([F-18]FDS) and 2-[F-18]F-rho-aminobenzoic acid ([F-18]FPABA), and also developed a simplified alternative of the latter for automated synthesis. Clinical and reference isolates of bacterial and yeast species (19 different strains in all) were tested in vitro and in an experimental mouse model of myositis infection. Results and discussionNon-lactose fermenters (Pseudomonas aeruginosa and Stenotrophomonas maltophilia) were unable to take up [F-18]FDG in vitro. [F-18]FDS PET was able to visualize Enterobacterales myositis infection (i.e., Escherichia coli) and to differentiate between yeasts with differential assimilation of sorbitol (i.e., Candida albicans vs. Candida glabrata). All bacteria and yeasts tested were detected in vitro by [F-18]FPABA. Furthermore, [F-18]FPABA was able to distinguish between inflammation and infection in the myositis mouse model (E. coli and Staphylococcus aureus) and could be used as a probe for a wide variety of bacterial and fungal species.

Published
2023

20. The value of the continuous genotyping of multi-drug resistant tuberculosis over 20 years in Spain

Author

Iglesias, M.J., Ibarz, D., Cebollada, A., Comín, J., Jiménez, M.S., Vázquez, M.C., Samper, S., Cabezas, T., Reyes, A., Ruiz, I., García, P., López, M.D., Cardeñoso, L., de la Calle, I.J., Ruiz, P., Alados, J.C., Román, J., Villa-Real, R., Saavedra, J., Amores, C., Bermúdez, P., Sánchez, M.A., Montiel, N., Bernal, S., Lepe, J.A., Batista, N., Roldán, E., Torres, L., Navarro, C., Chocarro, P., Aldea, M.J., Viñuelas, J., Vitoria, M.A., Palacios, J.J., Villar, H., Prendes, P., Blanco, M., Vázquez, F., Telenti, M., Sánchez, I., Carbo, L., Escobar, S., Ramírez, A., Gallegos, C., Pérez, M.C., Lecuona, M., Díez, O., Copado, R., Campos, I., Cañas, F., Salas, C., Fernández, C., Roíz, M.P., Barba, I., Manrique, E., Carranza, R., Maroto, A.S., González, A., Rodríguez, E., Martino, V., Sánchez, C., Martínez, C., Robles, P., Simarro, E., Romero, C., López, R., Blanco, M.D., Nebreda, T., Rodríguez, J., Fernández, J.M., Álvarez, E., Jaime, M.L., Tejero, M.D., Alberte, A., Oteda, E., Megías, G., Labayru, C., Ibáñez, R., Campos, A., Carrero, P., Villó, J.M., Sans, T., Pujol, I., Clivillé, X., Castellví, J.B., de Batlle, J., Mariscal, D., Prat, C., García, M., Alcalde, F., Gallén, C., Sauca, G., Cuchi, E., Alonso, C., Corcoy, F., Schmidt, G., Tortola, M.T., Garduño, E., Moreno, J.J., Hernández, P., Montes, I., Roman, J., Alonso, P., Rodríguez, A., Barbeyto, L., Fernández, B., Domínguez, D., Villanueva, R., Iglesias, I., Vasallo, F.J., Sevillano, J., Pascual, A., Pérez del Molino, M.L., Ugalde, E., Dopereiro, R., Cuadros, J.A., Pelayo, I., Cacho, J., Cogollos, R., Páez, M., Prieto, S., Fernández, R., López, P., Domingo, D., Millán, R., Bonilla, I., Merino, P., Toro, C., Ruiz, M.J., Menéndez, M., Romero, P., Tato, M., Simón, M., Urmeneta, A., Delgado, A., García, L., Cobos, J., Merino, J., Aznar, E., Piqueras, J., Navarro, M.D., Artero, J.M., Navascués, A., Gil, A., Leiva, J., Elorduy, L., Urra, E., Idígoras, P., Pérez-Trallero, E., Canut, A., Barrios, J.L., Michans, L., Ayarza, R., García, F., Unzaga, M.J., Navarro, M., Gonzalo, N., Martín, C., Gimeno, A., Elia, M., Sabater, S., Rodríguez, J.C., Santos, M., Bosque, M., López, J., Tabernero, E., Galán, M.I., Instituto de Salud Carlos III - ISCIII, and Instituto de Salud Carlos III

Subjects
Male, 0301 basic medicine, Genotyping Techniques, Extensively Drug-Resistant Tuberculosis, Minisatellite Repeats, 0302 clinical medicine, Drug Resistance, Multiple, Bacterial, Tuberculosis, Multidrug-Resistant, Epidemiology, Cluster Analysis, 030212 general & internal medicine, Child, Phylogeny, media_common, Molecular Epidemiology, Mycobacterium bovis, Multidisciplinary, biology, Multi-drug-resistant tuberculosis, Age Factors, Middle Aged, Phylogenetics, Exact test, Child, Preschool, Population Surveillance, Infectious diseases, Medicine, Female, Microbial genetics, Adult, medicine.medical_specialty, Tuberculosis, Adolescent, Science, Policy and public health in microbiology, Article, Young Adult, 03 medical and health sciences, medicine, Humans, media_common.cataloged_instance, European union, Clinical microbiology, Genotyping, Respiratory tract diseases, Molecular epidemiology, Health care, Infant, Newborn, Infant, Mycobacterium tuberculosis, medicine.disease, biology.organism_classification, 030104 developmental biology, Risk factors, Spain, Demography
Abstract

Molecular epidemiology of circulating clinical isolates is crucial to improve prevention strategies. The Spanish Working Group on multidrug resistant tuberculosis (MDR-TB) is a network that monitors the MDR-TB isolates in Spain since 1998. The aim of this study was to present the study of the MDR-TB and extensively drug-resistant tuberculosis (XDR-TB) patterns in Spain using the different recommended genotyping methods over time by a national coordinated system. Based on the proposed genotyping methods in the European Union until 2018, the preservation of one method, MIRU-VNTR, applied to selected clustered strains permitted to maintain our study open for 20 years. The distribution of demographic, clinical and epidemiological characteristics of clustered and non-clustered cases of MDR/XDR tuberculosis with proportion differences as assessed by Pearson's chi-squared or Fisher's exact test was compared. The differences in the quantitative variables using the Student's-t test and the Mann-Whitney U test were evaluated. The results obtained showed a total of 48.4% of the cases grouped in 77 clusters. Younger age groups, having a known TB case contact (10.2% vs 4.7%) and XDR-TB (16.5% vs 1.8%) were significantly associated with clustering. The largest cluster corresponded to a Mycobacterium bovis strain mainly spread during the nineties. A total of 68.4% of the clusters detected were distributed among the different Spanish regions and six clusters involving 104 cases were grouped in 17 and 18 years. Comparison of the genotypes obtained with those European genotypes included in The European Surveillance System (TESSy) showed that 87 cases had become part of 20 European clusters. The continuity of MDR strain genotyping in time has offered a widespread picture of the situation that allows better management of this public health problem. It also shows the advantage of maintaining one genotyping method over time, which allowed the comparison between ancient, present and future samples. The molecular methods applied in this work were supported by the Carlos III Health Institute in the context of two consecutive Grants FIS15/0317 and 18/0336 and JC was awarded a scholarship by the Government of Aragon / European Social Fund, “Building Europe from Aragon”. Sí

Published
2020

23. Difusión de humedad en mezclas de moldeo para machos de fundición

Author

Hernández-Ruiz, J. E., Valencia- Morales, E., Villar-Cociña, E., and Vega- Leiva, J.

Subjects
Moisture, diffusion and molding mixtures, Humedad, difusión y mezclas de moldeo, Clay industries. Ceramics. Glass, TP785-869
Abstract

The moisture diffusion in molding mixtures employing in foundry processes is described. Using gravimetric techniques the humectation kinetic behavior of different types of molding mixtures for foundry cores were registered. The mixture higroscopicity is compared using the porcentual increase in wet mass. The kinetic study is ending with the calculations effective coefficients of diffusion of the atmospheric water in the mixtures to different bleakness. For this goal the fitting through non lineal methods was used. The influences of the agglutinative and draw materials in the hygroscope properties of these were analyzed too.Se describe la difusión de humedad en mezclas de moldeo utilizadas en los procesos de fundición. Empleando técnicas gravimétricas se registra el comportamiento de la cinética de humectación de diferentes tipos de mezclas de moldeo para machos de fundición. La higroscopicidad de las mezclas es comparada usando el criterio del incremento porcentual en masa húmeda. El estudio cinético se concluye con los cálculos de los coeficientes efectivos de difusión del agua atmosférica en las mezclas a distintas intemperies. Para este propósito se emplean métodos de ajuste no lineal. También se analiza la influencia de los materiales aglutinantes y desarenantes en las propiedades higroscópicas de estas mezclas.

Published
2002

32. Registered report protocol: Evaluation of a contextualized teaching evaluation project

Author

Leiva J, Matas-Terron A, and Caballero Pdf

Subjects
World Wide Web, Protocol evaluation, Computer science
Abstract

Teacher evaluation can be an underused resource for teaching improvement, as it is reduced to a single questionnaire to be answered by students. The lack of flexibility and adaptability prevents them from developing their potential. This paper provides a record of the protocol that is being applied in a relation to an educational innovation project that aims to develop a contextualized alternative to the current system of teaching assessment that is being carried out at the University of Malaga (Spain). For this purpose, an evaluation based on the Contribution Analysis is being carried out (Mayne, 2008). This procedure is based on the project’s Theory of Change (Roger, 2014) from which a procedure is established to confirm the causality of the changes observed. The procedure is currently underway and the first partial results are expected by the end of 2021. The results of the evaluation will make it possible to assess the efficiency of the project, as well as its capacity to solve the problems of questionnaire-based teaching evaluation. Resumen La evaluación docente puede ser un recurso infrautilizado para la mejora de la enseñanza, ya que se reduce a un solo cuestionario para ser respondido por los estudiantes. La falta de flexibilidad y adaptabilidad les impide desarrollar su potencial. Este artículo proporciona un registro del protocolo que se está aplicando en relación a un proyecto de innovación educativa que tiene como objetivo desarrollar una alternativa contextualizada al actual sistema de evaluación docente que se está llevando a cabo en la Universidad de Málaga (España). Para ello, se está realizando una evaluación basada en el Análisis de Contribuciones (Mayne, 2008). Este procedimiento se basa en la Teoría del Cambio del proyecto (Roger, 2014) a partir del cual se establece un procedimiento para confirmar la causalidad de los cambios observados. El procedimiento está actualmente en curso y se esperan los primeros resultados parciales para finales de 2021. Los resultados de la evaluación permitirán valorar la eficacia del proyecto, así como su capacidad para resolver los problemas de evaluación docente mediante cuestionarios.

Published
2021
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34. Azole and Amphotericin B MIC Values against Aspergillus fumigatus: High Agreement between Spectrophotometric and Visual Readings Using the EUCAST EDef 9.3.2 Procedure

Author

Serrano-Lobo, J., Gómez, A., Sánchez-Yebra, W., Fajardo, M., Lorenzo, B., Sánchez-Reus, F., Vidal, I., Fernández-Torres, M., Sánchez-Romero, I., de Alegría-Puig, C.R., del Pozo, J.L., Muñoz, P., Escribano, P., Guinea, J., Sánchez-Gómez, J., Lozano, I., Marfil, E., de la Rosa, M.M., García, R.T., Cobo, F., Castro, C., López, C., Rezusta, A., Peláez, T., Castelló-Abietar, C., Cos-Tales, I., Serra, J.L., Jiménez, R., Echeverría, C.L., Pérez, C.L., Megías-Lobón, G., Ayats, J., Martín, M.T., Sánchez-Hellín, V., Ibáñez, E., Pemán, J., Pazos, C., Rodríguez-Mayo, M., Pérez-Ayala, A., Gómez, E., Serrano, J., Reigadas, E., Rodríguez, B., Zvezdanova, E., Díaz-García, J., González Leiva, J., Machado, M., García-Rodríguez, J., Vallejo, M.R., López-Soria, L., Marimón, J.M., Vicente, D., and Hernáez-Crespo, S.

Subjects
Azoles, Posaconazole, Antifungal Agents, Itraconazole, Microbial Sensitivity Tests, azoles, Microbiology, Aspergillus fumigatus, 03 medical and health sciences, 0302 clinical medicine, EUCAST, Drug Resistance, Fungal, Amphotericin B, parasitic diseases, medicine, Pharmacology (medical), spectrophotometric, 030212 general & internal medicine, Pharmacology, chemistry.chemical_classification, Voriconazole, 0303 health sciences, Aspergillus, biology, 030306 microbiology, biology.organism_classification, bacterial infections and mycoses, Infectious Diseases, chemistry, amphotericin B, Mic values, Azole, medicine.drug
Abstract

The EUCAST EDef 9.3.2 procedure recommends visual readings of azole and amphotericin B MICs against Aspergillus spp. Visual determination of MICs may be challenging. In this work, we aim to obtain and compare visual and spectrophotometric MIC readings of azoles and amphotericin B against Aspergillus fumigatus sensu lato isolates. A total of 847 A. fumigatus sensu lato isolates (A. fumigatus sensu stricto [n = 828] and cryptic species [n = 19]) were tested against amphotericin B, itraconazole, voriconazole, posaconazole, and isavuconazole using the EUCAST EDef 9.3.2 procedure. Isolates were classified as susceptible or resistant/non-wild type according to the 2020 updated breakpoints. The area of technical uncertainty for the azoles was defined in the updated breakpoints. Visual and spectrophotometric (fungal growth reduction of >95% compared to the control, read at 540 nm) MICs were compared. Essential (±1 2-fold dilution) and categorical agreements were calculated. Overall, high essential (97.1%) and categorical (99.6%) agreements were found. We obtained 100% categorical agreements for amphotericin B, itraconazole, and posaconazole, and consequently, no errors were found. Categorical agreements were 98.7 and 99.3% for voriconazole and isavuconazole, respectively. Most of the misclassifications for voriconazole and isavuconazole were found to be associated with MIC results falling either in the area of technical uncertainty or within one 2-fold dilution above the breakpoint. The resistance rate was slightly lower when the MICs were obtained by spectrophotometric readings. However, all relevant cyp51A mutants were correctly classified as resistant. Spectrophotometric determination of azole and amphotericin B MICs against A. fumigatus sensu lato isolates may be a convenient alternative to visual endpoint readings.

Published
2020

40. First national survey of the diagnosis of Helicobacter pylori infection in Clinical Microbiology Laboratories in Spain

Author

Miqueleiz-Zapatero A, Alba-Rubio C, Domingo-Garcia D, Canton R, de la Pedrosa E, Aznar-Cano E, Leiva J, Montes M, Sanchez-Romero I, Rodriguez-Diaz J, Alarcon-Cavero T, and Grp Trabajo Diagnost Microbiol Hel

Subjects
Helicobacter pylori, Gastric biopsy, Microbiological diagnosis, Survey, Techniques
Abstract

Introduction: The aim of this study was to know, through a national survey, the methods and techniques used for the diagnosis of Helicobacter pylori (Hp) in the different Clinical Microbiology Services/Laboratories in Spain, as well as antibiotic resistance data. Methods: The survey requested information about the diagnostic methods performed for Hp detection in Clinical Microbiology laboratories, including serology, stool antigen, culture from gastric biopsies, and PCR. In addition, the performance of antibiotic susceptibility was collected. Data on the number of samples processed in 2016, positivity of each technique and resistance data were requested. The survey was sent by email (October-December 2017) to the heads of 198 Clinical Microbiology Laboratories in Spain. Results: Overall, 51 centers from 29 regions answered the survey and 48/51 provided Hp microbiological diagnostic testing. Concerning the microbiological methods used to diagnose Hp infection, the culture of gastric biopsies was the most frequent (37/48), followed by stool antigen detection (35/48), serology (19/48) and biopsy PCR (5/48). Regarding antibiotic resistance, high resistance rates were observed, especially in metronidazole and clarithromycin (over 33%). Conclusion: Culture of gastric biopsies was the most frequent method for detection of Hp, but the immunochromatographic stool antigen test was the one with which the largest number of samples were analyzed. Nowadays, in Spain, it concerns the problem of increased antibiotic resistance to 'first-line' antibiotics. (C) 2019 Elsevier Espana, S.L.U. and Sociedad Espanola de Enfermedades Infecciosas y Microbiologia Clinica. All rights reserved.

Published
2020

47. Association between depressive symptoms and disability in older adults of 12 high Andean communities from Peru.

Author

Valenzuela‐Iglesias, Mia F., Ccama‐Leiva, J. Lorena, Urrunaga‐Pastor, Diego, Runzer‐Colmenares, Fernando M., and Parodi, José F.

Subjects
*OLDER people, *MOUNTAIN sickness, *MENTAL depression, *REMINISCENCE therapy, *GERIATRIC Depression Scale, *POISSON regression, *MEDICAL care
Abstract

Objective: Our objective was to evaluate the association between depressive symptoms and disability in older adults residing in 12 high Andean communities in Peru. Material and Methods: We carried out a secondary data analysis of a cross‐sectional study that included older adults (60 years or older) from 12 high Andean communities in Peru from 2013 to 2019. Depressive symptoms were defined as a score of two or more in the abbreviated Geriatric Depression Scale, while disability was defined as a score of less than 95 in the Barthel index. We also included sociodemographic characteristics, medical and personal history, and functional and performance‐based tests. We used crude and adjusted Poisson regression models to evaluate the association of interest and estimated prevalence ratios (PR) with their respective 95% confidence intervals (95% CI). Results: We included 442 older adults with a mean age of 73 ± 6.9 in the analysis; 63.1% (n = 279) were women, and 79.9% (n = 353) had no education or incomplete primary school. 50.9% (n = 225) of the participants had depressive symptoms, and 49.8% (n = 220) had disability. The adjusted Poisson regression model showed that depressive symptoms increased the probability of disability (adjusted PR = 1.67; 95% CI: 1.34–2.08; p < 0.001) in older adults living at high altitude. Conclusions: Depressive symptoms was associated with a greater probability of disability in older adults living at high altitude. Longitudinal studies are needed for better understanding of this association in high altitude populations along with timely interventions to reduce the impact of both geriatric syndromes. Key points: Approximately one in two older adults from high Andean communities had depressive symptoms or disabilityDepressive symptoms was associated with a greater probability of disability in older adults living at high altitudeTo our knowledge, this is the first study that evaluates the association between depressive symptoms and disability in elderly residents in high altitude communitiesIt is relevant to improve health services at the primary health care level to generate timely interventions and reduce the impact of depression and disability in this population group [ABSTRACT FROM AUTHOR]

Published
2022
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