Performance of parallel FDTD method for shared- and distributed-memory architectures: Application tobioelectromagnetics.

This work provides an in-depth computational performance study of the parallel finite-difference time-domain (FDTD) method. The parallelization is done at various levels including: shared- (OpenMP) and distributed- (MPI) memory paradigms and vectorization on three different architectures: Intel's Knights Landing, Skylake and ARM's Cavium ThunderX2. This study contributes to prove, in a systematic manner, the well-established claim within the Computational Electromagnetic community, that the main factor limiting FDTD performance, in realistic problems, is the memory bandwidth. Consequently a memory bandwidth threshold can be assessed depending on the problem size in order to attain optimal performance. Finally, the results of this study have been used to optimize the workload balancing of simulation of a bioelectromagnetic problem consisting in the exposure of a human model to a reverberation chamber-like environment.

Re-certification of hydroxyvitamin D standards by isotope pattern deconvolution.

BACKGROUND: Vitamin D testing in analytical clinical laboratories has been experiencing a rapid increase of demand over the last years, as it plays a key role in several disorders. Due to the narrow ranges of medical significance regarding its concentration levels in human serum, accurate and precise determinations of vitamin D metabolites are required. METHODS: We present an isotope dilution mass spectrometry quantification method for the re-certification of routine commercial standards used in method validation steps, isotope pattern deconvolution (IPD) based on LC-MS/MS. RESULTS: IPD allowed to compensate for the observed biases of +4.7% for 25(OH)D3, -29% for 25(OH)D2 and -30% for 24,25(OH)2D3 standard concentrations, respectively in an easy, cheap and straightforward way. CONCLUSIONS: Is has been observed that, in some cases, discrepancies may exist between stated purity or amount of routinely used commercial standards and actual values, which would lead to unwanted bias in the developed methodologies. The present correction has helped meeting the regulations established by international standardization programs, including Vitamin D Standardization Program (VDSP).

Comparison of isotope pattern deconvolution and calibration curve quantification methods for the determination of estrone and 17ß-estradiol in human serum.

A Liquid Chromatography coupled to tandem mass spectrometry (LC-MS/MS) based method have been developed for the determination of the main estrogen compounds -estrone (E1) and 17ß-estradiol (E2)- in human serum. Two isotope dilution mass spectrometry (IDMS) quantification procedures have been used: a classical calibration curve-based method were compared to a recently developed isotope pattern deconvolution (IPD) method. IPD is based on isotopic abundance measurements and multiple linear regression. Validation was performed in terms of intra-assay repeatability (n = 5), inter-assay reproducibility (n = 9) and accuracy using spiked steroid-free serum at 5 concentration levels and 3 certified reference materials. Both methodologies meet EMEA requirements yielding recoveries between 79-106% and coefficient of variations of 1.7-8.3% along all experiments. Limits of quantification as low as 5 ng/L were achieved. 40 real samples were analysed for comparison purposes showing a great correlation between calibration and IPD concentration values. Real samples were also quantified by routine immunoassay analysis, which showed a significant proportional bias of 2.55 for E1 and good correlation for E2. While methods were considered suitable for routine or countercheck analysis within the context of hospital's needs, IPD has demonstrated to be faster and cost saving.

Evaluation of uncertainty sources in the determination of testosterone in urine by calibration-based and isotope dilution quantification using ultra high performance liquid chromatography tandem mass spectrometry.

Three quantification methodologies, namely calibration with internal standard (Cal-IS, non-weighted), weighted calibration with internal standard (wCal-IS) and isotope pattern deconvolution (IPD) have been used for the determination of testosterone in urine by LC-MS/MS. Uncertainty has been calculated and compared for the three methodologies through intra- and inter-laboratory reproducibility assays. IPD showed the best performance for the intra-laboratory reproducibility, with RSD and combined uncertainty values below 4% and 9% respectively. wCal-IS showed similar performance, while Cal-IS where not constant and clearly worse at the lowest concentration assayed (2ng/mL) reaching RSD values up to 16%. The inter-laboratory assay indicated similar results although wCal-IS RSD (20%) was higher than IPD (10%) and Cal-IS get worse with RSD higher than 40% for the lowest concentration level. Uncertainty budgets calculated for the three procedures revealed that intercept and slope were the most important factors contributing to uncertainty for Cal-IS. The main factors for wCal-IS and IPD were the volumes of sample and/or standard measured.

Atypical presentation in adults in the largest community outbreak of leishmaniasis in Europe (Fuenlabrada, Spain).

Since 2009, the largest reported outbreak of leishmaniasis by Leishmania infantum in Europe was reported in Fuenlabrada, Spain. In our hospital, 90 adults with localized leishmanial lymphadenopathy (LLL) or visceral leishmaniasis (VL) were treated during this outbreak; 72% were men, and the mean age was 46.2 years (range 15-95 years). A total of 17 cases (19%) were LLL, an atypical form with isolated lymphadenopathies without other symptoms. All LLL cases occurred in immunocompetent subjects, and only one subject (6%) was a native of sub-Saharan Africa. Diagnosis was performed by fine needle aspiration cytology of the lymphadenopathy. Serology was negative in 38%. LLL outcomes at 6 months were benign, even with doses of liposomal amphotericin B that were often lower (10 mg/kg) than those recommended for VL in Mediterranean areas. A total of 73 subjects (81%) presented with typical VL; 66% of this group were immunocompetent, and 50% of those who were immunocompetent were descendants of natives of sub-Saharan Africa. The rK39 test and polymerase chain reaction were the most useful tests for confirmation of the diagnosis. An initial response to treatment was observed in 99% of cases, and relapses occurred in 14% of cases. Leishmaniasis should be included in the differential diagnosis of isolated lymphadenopathies in endemic areas. LLL could be considered a more benign entity, one different than VL, and less aggressive management should be studied in future investigations.

Efecto de la contaminación con hidrocarburos sobre hongos formadores de micorrizas vesículo-arbusculares (mva) / Effect of hydrocarbon pollution on vesicular arbuscular mycorrhizal fungi (vam)

Se estudió el efecto de hidrocarburos sobre hongos formadores de micorrizas vesículo-arbusculares (MVA) en condiciones de campo y de laboratorio. Plantas de alfalfa (Medicago sativa) con y sin inoculación del endófitoGlomus mosseae, fueron transplantadas en el campo en parcelas contaminadas con hidrocarburos y en parcelas testigo no contaminadas. El mismo ensayo se realizó en condiciones de laboratorio en macetas, para lo cual se probaron 2 endófitos: G. mosseae y G. fasciculatum. La contaminación con hidrocarburo, tanto en condiciones de campo como de laboratorio, redujo la colonización en las raices. En el campo, en el suelo contaminado, los niveles más altos de colonización se produjeron cuando las plantas se inocularon previamente y en laboratorio, cuando el hongo MVA colonizó la raíz antes del contacto con el hidrocarburo. G. fasciculatum mostró ser más eficiente que G. mosseae en el crecimeinto de plantas de alfalfa

Efecto de la aplicación secuencial de fungicidas sobre hongos formadores de micorrizas vesiculo-arbusculares en condiciones de campo / Effect of sequential application of fungicides on vesicular-arbuscular mycorrhizal fungi in field conditions

Se estudió en condiciones de campo, el efecto de la aplicación secuencial de los fungicidas benomilo (sistémico) y mancozeb (de contacto) sobre la colonización vesículo-arbuscular en raíces de plantas de trigo y sobre la producción de esporas de hongos formadores de micorrizas vesículo-arbusculares. Estos fungicidas no afectaron la evolución de la colonización micorrizica de las raíces la cual siguió una curva sigmoide típica en todos los tratamientos; pero hicieron que variara la calidad de la misma, reduciendo el porcentaje de arbúsculos y aumentando el número de vesículas. Sin embargo la aplicación secuencial produjo una disminución del "plateau" de las curvas en las parcelas tratadas cuando se las compara con la testigo. El número de las esporas en el suelo no fue afectada por estos tratamientos

Efecto de la contaminación con hidrocarburos sobre geohongos saprotropos / Effect of hydrocarbon pollution on saprotrophic soil fungi

Se investigó la variación de la micota saprotrofa de suelos contaminados con hidrocarburos y testigos. El número de propágulos fúngicos en los suelos contaminados fue mucho menor que en el testigo. Aspergillus foetidus y A. niger fueron muy afectados por la contaminación. Cylindrocarpon didymun, Fusarium solani y Penicillium restrictum mantuvieron sus frecuencias en la parcela contaminada en relación a la testigo. Penicillium thomii (en profundidad), Talaromyces helicus y T. rotundus tuvieron frecuencias más altas en la parcela contaminada que en la testigo. Rhizoctonia sp. (en superficie) y Trichoderma harzianum aumentaron sus frecuencias en la parcela contaminada al final del ensayo. Las relaciones de los isoprenoides con sus respectivos normales (pristano nC17 y fitano nC18) demostraron que la degradación del hidrocarburo en el suelo fue escasa

Interacciones entre hongos formadores de micorrizas vesiculo-arbusculares (vam) y bradyhizomium; su efecto en el crecimiento de la soja (glicine max) / Interactions between fungi producers of vesicular-arbuscular mycorrhizal (vam) and bradyrhizobium: it effect over soybean growth (glicine max)

Se estudió la interacción entre hongos vam nativos de suelos agrícolas de la provincia de Buenos Aires (Argentina), Glomus epigaeus y Bradyrhizobium japonicum en plantas de soja. La inoculación tripartita: vam nativas, G. epigaeus y B. japonicum produjeron plantas más vigorosas, con mayor número de nódulos y de mayor tamaño en relación a plantas no inoculadas. El contenido de nitrogeno en la porción aérea de las plantas aumentó un 102 porciento y el del fósforo un 233 porciento en plantas con inoculación tripartita, en relación al testigo no inoculado