Influence of Zn excess on compositional, structural and vibrational properties of Cu2ZnSn0.5Ge0.5Se4 thin films and their effect on solar cell efficiency

This Accepted Manuscript will be available for reuse under a CC BY-NC-ND licence after 24 months of embargo periodThe effect of Zn content on compositional, structural and vibrational properties of Cu2ZnSn1-xGexSe4 (CZTGSe, x ~ 0.5) thin films is studied. Kesterite layer is deposited by co-evaporation onto 5 × 5 cm2 Mo/SLG substrate followed by a thermal treatment at maximum temperature of 480 °C, obtaining areas with different composition and morphology which are due to the sample position in the co-evaporation system and to the non-uniform temperature distribution across the substrate. Kesterite layers with higher Zn amounts are characterized by lower Cu and Ge contents; however, a uniform Ge distribution through the absorber layer is detected in all cases. The excess Zn concentration leads to the formation of ZnSe secondary phase on the surface and in the bulk of the absorber as determined by Raman spectroscopy. When higher Ge content and no ZnSe are present in the absorber layer, a compact structure is formed with larger grain size of kesterite. This effect could explain the higher Voc of the solar cell. The Zn content does not affect the bandgap energy significantly (Eg near 1.3 eV), although the observed effect of Zn excess in CZTGSe results in a decreased device performance from 6.4 to 4.2%. This investigation reveals the importance of the control of the off-stoichiometric CZTGSe composition during the deposition process to enhance solar cells propertiesThis work was supported by Spanish Ministry of Science, Innovation and Universities Project WINCOST (ENE2016-80788-C5-2-R) and European Project INFINITE CELL (H2020-MSCA-RISE-2017-777968). ARP also acknowledges financial support from Community of Madrid within Youth Employment Program (PEJD-2017-PRE/IND-4062). MG acknowledges the financial support from ACCIÓ-Generalitat de Catalunya within the TECNIOspring Plus fellowship (TECSPR18-1-0048

Caracterización química y cuantificación del rendimiento de extracción de pigmento en siete accesiones mexicanas de Bixa orellana

Achiote (Bixa orellana) is a plant used for obtaining a natural dye rich on carotenoids (mainly bixin and norbixin); it is also the plant species with the highest content of tocotrienols in nature. In the present work, the pigment extraction yield of seven Mexican accessions of Bixa orellana was quantified. Also color parameters and content of tocotrienols, tocopherols, norbixin, bixin, total phenolic compounds and antioxidant capacity were evaluated in the corresponding annatto extracts. The highest percentage of pigment extraction yield was obtained with KOH (4.84%). Accessions 43 (L*= 4.01 ± 0.79, C*= 7.33 ± 1.07, h= 25.76 ± 6.35) and 50 (L*= 3.17 ± 0.64, C*= 6.81 ± 0.53, h= 26.41 ± 4.41) had the lowest color values, meaning these accessions had a darker and redder color. Four accessions showed the highest content of bixin: accession 48 (3.1%), 45 (2.6%) 43 (2.4%) and 47 (2.2%). Accession 50 had showed the highest content of total phenolic compounds and of tocotrienols (T3), mainly the isoform δ-T3 (5.03 ± 0.64 mg g−1 Seed Dry Weight), as well as the highest antioxidant capacity.El achiote (Bixa orellana) es una planta utilizada para obtener un colorante natural rico en carotenoides (principalmente bixina y norbixina); además, es la especie vegetal con el mayor contenido de tocotrienoles. En este trabajo, se determinó el rendimiento de extracción de pigmento de siete accesiones mexicanas de Bixa orellana. También se evaluaron los parámetros de color y el contenido de tocotrienoles, tocoferoles, norbixina, bixina, compuestos fenólicos totales y la capacidad antioxidante en extractos de annato. El mayor porcentaje de rendimiento de extracción de pigmento fue obtenido con KOH (4.847905%). Las accesiones 43 (L*= 4.01 ± 0.79, C*= 7.33 ± 1.07, h= 25.76 ± 6.35) y 50 (L*= 3.17 ± 0.64, C*= 6.81 ± 0.53, h= 26.41 ± 4.41) presentaron los valores más bajos de los párametros de color, lo que significa que estas accesiones tuvieron un color más oscuro y más rojo. Cuatro accesiones mostraron el mayor contenido de bixina: accesión 48 (3.1%), 45 (2.6%) 43 (2.4%) and 47 (2.2%). La accession 50 mostró el mayor contenido de compuestos fenólicos totales y de tocotrienoles (T3), principalmente la isoforma δ-T3 (5.03 ± 0.64 mg g-1 Peso Seco), así como también la mayor capacidad antioxidante.Fil: Raddatz Mota, D.. Universidad Autónoma Metropolitana; MéxicoFil: Pérez Flores, L. J.. Universidad Autónoma Metropolitana; MéxicoFil: Carrari, Fernando Oscar. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Insani, Ester Marina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Asis, Ramón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Mendoza Espinoza, J. A.. Universidad Nacional Autónoma de México; MéxicoFil: Díaz de León Sánchez, F.. Universidad Autónoma Metropolitana; MéxicoFil: Rivera Cabrera, F.. Universidad Autónoma Metropolitana; Méxic

Automatic calculation of pelvis morphology from CT images

Pelvimetry is the study of the pelvis morphology in women for labor planning and medical assessment. This can be achieved by manually annotating pelvic CT images for extracting several measures of interest, which can be both time-consuming and subjective. While machine learning has achieved significant success in 2D landmarking applications, results in pelvic CT images are still limited, particularly with small datasets. This paper presents a two-step approach for detecting 3D landmarks in pelvic CT images. First, a simple CNN coarsely estimates landmark locations, serving as a starting point for further refinement. Then, higher resolution 3D patches and independent neural networks are used to obtain the final position for each landmark. Our model has shown promising results, obtaining an average distance error of 6.71 mm across 7 landmarks. These values allowed the calculation of the morphological measurements, demonstrating a strong correlation with the manual values. The proposed model has shown promising results, offering efficient and accurate predictions of the anatomical landmarks in CT examinations

A chemical genetic screen reveals a role for proteostasis in capsule and biofilm formation by Cryptococcus neoformans

Pathogenic microorganisms employ specialized virulence factors to cause disease. Biofilm formation and the production of a polysaccharide capsule are two important virulence factors in Cryptococcus neoformans, the fungal pathogen that causes meningoencephalitis. Here, we show that the bipolar disorder drug lithium inhibits formation of both virulence factors by a mechanism involving dysregulation of the ubiquitin/proteasome system. By using a chemical genetics approach and bioinformatic analyses, we describe the cellular landscape affected by lithium treatment. We demonstrate that lithium affects many different pathways in C. neoformans, including the cAMP/protein kinase A, inositol biosynthesis, and ubiquitin/proteasome pathways. By analyzing mutants with defects in the ubiquitin/proteasome system, we uncover a role for proteostasis in both capsule and biofilm formation. Moreover, we demonstrate an additive influence of lithium and the proteasome inhibitor bortezomib in inhibiting capsule production, thus establishing a link between lithium activity and the proteasome system. Finally, we show that the lithium-mimetic drug ebselen potently blocks capsule and biofilm formation, and has additive activity with lithium or bortezomib. In summary, our results illuminate the impact of lithium on C. neoformans, and link dysregulation of the proteasome to capsule and biofilm inhibition in this important fungal pathogen

High-level quinolone resistance is associated with the overexpression of smeVWX in Stenotrophomonas maltophilia clinical isolates

AbstractStenotrophomonas maltophilia is the only known bacterium in which quinolone-resistant isolates do not present mutations in the genes encoding bacterial topoisomerases. The expression of the intrinsic quinolone resistance elements smeDEF, smeVWX and Smqnr was analysed in 31 clinical S. maltophilia isolates presenting a minimum inhibitory concentration (MIC) range to ciprofloxacin between 0.5 and > 32 μg/mL; 11 (35.5%) overexpressed smeDEF, 2 (6.5%) presenting the highest quinolone MICs overexpressed smeVWX and 1 (3.2%) overexpressed Smqnr. Both strains overexpressing smeVWX presented changes at the Gly266 position of SmeRv, the repressor of smeVWX. Changes at the same position were previously observed in in vitro selected S. maltophilia quinolone-resistant mutants, indicating this amino acid is highly relevant for the activity of SmeRv in repressing smeVWX expression. For the first time SmeVWX overexpression is associated with quinolone resistance of S. maltophilia clinical isolates

Influence of volume and bouts of sedentary time and physical activity on school-aged youth’s physical fitness: The UP&DOWN longitudinal study

Background: The aim of this study was to examine associations of total volume and bouts of sedentary time (ST) and moderate to vigorous physical activity (MVPA) with physical fitness (PF) in youth. Methods: This was a 2-year follow-up study with 1418 children and adolescents (51.7% boys). Accelerometers were used to assess ST and MVPA. Cardiorespiratory and muscular fitness values were objectively measured and combined in a global PF variable. Weight status was objectively obtained. Linear regression analyses were used to examine the cross-sectional (using scores at baseline) and longitudinal associations (using the change in the variables) of total volume and bouts of ST and MVPA with PF. Results: Total ST was negatively associated with global PF (β = −0.488, P < .001 in cross-sectional analysis; β = −0.234, P = .003 in longitudinal analysis). However, this association was not independent of MVPA. Total volume of MVPA showed a positive association with global PF independently of ST and weight status (β = 0.285, P < .001 in cross-sectional analysis; β = 0.119, P = .001 in longitudinal analysis). Longitudinal associations found between ST and MVPA accumulated in bouts of various lengths and global PF became nonsignificant when their respective total volumes are included in the model. Conclusions: These results underline the need to accumulate minutes of MVPA, regardless of the bout duration, to increase PF levels in yout

ANTIMICROBIAL ACTIVITY OF MEDICINAL PLANTS FROM THE HUAUTLA SIERRA BIOSPHERE RESERVE IN MORELOS (MÉXICO)

Twenty-two extracts from nine Mexicanmedicinal plants of eight different familiesused for people neighbor to Huautla SierraBiosphere Reserve (REBIOSH) in differentinfectious diseases were assayed in vitro todetermine their antibacterial activity againstStaphylococcus aureus, Streptococcus faecalis; Escherichia coli; Proteus mirabilis;Salmonella typhi and the yeast Candidaalbicans. Most plants showed antibacterialactivity, while two plants showed activityagainst range 0.25 a 4 mg/mL almost onemicroorganism used. The extracts showedminimum inhibitory concentration (MIC)against S. aureus and S. faecalis, representsmicroorganisms Gram-positive were hexanic and acetonic extracts of Bursera copallifera and hexanic extract of B. grandifolia.The ethanol extract of Lippia graveolensshowed a MIC value of 1 mg/mL againstyeast Candida albicans.Se determinó la actividad antimicrobianade veintidós extractos orgánicos de nueveespecies vegetales medicinales de ochodiferentes familias, que son comúnmenteempleadas por los habitantes de las comunidades vecinas a la reserva de la biosferaSierra de Huautla (REBIOSH), Morelos,para tratar diferentes padecimientos infecciosos. Los microorganismos empleadosfueron: Staphylococcus aureus; Streptococcus faecalis; Escherichia coli; Proteusmirabilis; Salmonella typhi y la levaduraCandida albicans. La mayoría de los extractos de las plantas probadas inhibieronel crecimiento microbiano en un rango de0.25 a 4 mg/mL de al menos uno de losmicroorganismos utilizados. Los extractosque mostraron las menores concentracionesmínimas inhibitorias (CMI) frente a losmicroorganismos S. aureus y S. faecalis,representativos de Gram-positivos fueron el extracto hexánico y acetónico de Burseracopallifera y el hexánico de B. grandifolia.El extracto etanólico de Lippia graveolenslogró inhibir a C. albicans con una CMIde 1 mg/mL

Microwave energy supplied by a prototype oven prevents the spread of Fusarium wilt during the propagation of melon plantlets by seed

The re-use of propagation trays in nursery greenhouses is one of the main ways in which fusarium wilt is spread in melon crops (Cucumis melo). The causal agent of the disease is the fungus Fusarium oxysporum f. sp. melonis. This paper reports that exposing these seed trays to the energy produced by a prototype microwave oven during the commercial production of melon plantlets can prevent the spread of this pathogen with only a very small increase in production costs

Ionic conductivity of nanocrystalline yttria-stabilized zirconia: grain boundary and size effects

We report on the effect of grain size on the ionic conductivity of yttria-stabilized zirconia samples synthesized by ball milling. Complex impedance measurements, as a function of temperature and frequency are performed on 10 mol % yttria-stabilized zirconia nanocrystalline samples with grain sizes ranging from 900 to 17 nm. Bulk ionic conductivity decreases dramatically for grain sizes below 100 nm, although its activation energy is essentially independent of grain size. The results are interpreted in terms of a space-charge layer resulting from segregation of mobile oxygen vacancies to the grain-boundary core. The thickness of this space-charge layer formed at the grain boundaries is on the order of 1 nm for large micron-sized grains but extends up to 7 nm when decreasing the grain size down to 17 nm. This gives rise to oxygen vacancies depletion over a large volume fraction of the grain and consequently to a significant decrease in oxide-ion conductivity