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© 2022 Elsevier B.V. All rights reserved., The present study employed data collected during the Mycosands survey to investigate the environmental factors influencing yeasts and molds distribution along European shores applying a species distribution modelling approach. Occurrence data were compared to climatic datasets (temperature, precipitation, and solar radiation), soil datasets (chemical and physical properties), and water datasets (temperature, salinity, and chlorophyll-a concentration) downloaded from web databases. Analyses were performed by MaxEnt software. Results suggested a different probability of distribution of yeasts and molds along European shores. Yeasts seem to tolerate low temperatures better during winter than molds and this reflects a higher suitability for the Northern European coasts. This difference is more evident considering suitability in waters. Both distributions of molds and yeasts are influenced by basic soil pH, probably because acidic soils are more favorable to bacterial growth. Soils with high nitrogen concentrations are not suitable for fungal growth, which, in contrast, are optimal for plant growth, favored by this environment. Finally, molds show affinity with soil rich in nickel and yeasts with soils rich in cadmium resulting in a distribution mainly at the mouths of European rivers or lagoons, where these metals accumulate in river sediments., Ana Sampaio thanks to the Foundation for Science and Technology and FEDER under Programe PT2020 for financial support to CITAB (UID/AGR/04033/2020)

Chirality and morphology are essential factors for protein function and interactions with other biomacromolecules. Extracellular matrix (ECM) proteins are also similar to other proteins in this sense; however, the complexity of the natural ECM makes it difficult to study these factors at the cellular level. The synthetic peptide nanomaterials harbor great promise in mimicking specific ECM molecules as model systems. In this work, we demonstrate that mechanosensory responses of stem cells are directly regulated by the chirality and morphology of ECM-mimetic peptide nanofibers with strictly controlled characteristics. Structural signals presented on l-amino acid containing cylindrical nanofibers (l-VV) favored the formation of integrin β1-based focal adhesion complexes, which increased the osteogenic potential of stem cells through the activation of nuclear YAP. On the other hand, twisted ribbon-like nanofibers (l-FF and d-FF) guided the cells into round shapes and decreased the formation of focal adhesion complexes, which resulted in the confinement of YAP proteins in the cytosol and a corresponding decrease in osteogenic potential. Interestingly, the d-form of twisted-ribbon like nanofibers (d-FF) increased the chondrogenic potential of stem cells more than their l-form (l-FF). Our results provide new insights into the importance and relevance of morphology and chirality of nanomaterials in their interactions with cells and reveal that precise control over the chemical and physical properties of nanostructures can affect stem cell fate even without the incorporation of specific epitopes.

Different properties of substrates based on tung compost (TC), carbonized rice husk (CRH) and earthworm humus (H) were analyzed, besides the effect of the formulations on the production of lettuce seedlings, cv. Veneranda. The experiment was carried out in Pelotas, Rio Grande do Sul State, Brazil, from December 2012 to February 2013, in a greenhouse, using completely randomized design with seven treatments and three replications. The used substrates were formulated on a volume basis: T1= commercial substrate S10® (control); T2= 90% carbonized rice husk (CRH) + 10% humus (H); T3= 75% CRH + 15% tung compost (TC) + 10% H; T4= 55% CRH + 35% TC + 10% H; T5= 35% CRH + 55% TC + 10% H; T6= 15% CRH + 75% TC + 10% H; T7= 90% TC + 10% H. Seedlings were produced in polystyrene trays with 200 cells, being evaluated 35 days after sowing. The substrate with larger proportion of CRH (T2 with 90% CRH) showed suitable dry density (DD) and total porosity (TP), high pH and aeration space (AS), low easily available water (EAW), electric conductivity (EC), and nutrient content, constituting an inert substrate, not being indicated as substrate due to the lower development of the seedlings. Using 15% TC, an increase was noticed in DD, AEW, EC and nutrients and, a decrease in TP, AS and pH due to, mainly, the size of tung compost particles, which accommodated themselves and altered physical and chemical properties of the substrates. Substrates with 90% and 75% TC (T7 and T6) provided the greatest shoot length, fresh and dry shoot mass and leaf area for lettuce seedlings due to higher nutrient content, also considering physical and chemical properties of these substrates. Pure CRH is not indicated to be used as substrate, but mixed with tung compost (T6), it provides high quality seedlings. Tung compost was effective in producing lettuce seedlings, since the composting is able to eliminate phytotoxic substances from this material which can hinder the seedling growth. RESUMO Analisou-se diferentes características em substratos a base de composto de tungue (TC), casca de arroz carbonizada (CRH) e húmus de minhoca (H), assim como, o efeito das formulações na produção de mudas de alface, cv. Veneranda. O experimento foi realizado no município de Pelotas-RS, de dezembro de 2012 a fevereiro de 2013, em casa de vegetação, utilizando delineamento experimental inteiramente casualizado com sete tratamentos e três repetições. Os substratos utilizados foram formulados em base de volume: T1= substrato comercial S10® (controle); T2= 90% CRH + 10% H; T3= 75% CRH + 15% TC + 10% H; T4= 55% CRH + 35% TC + 10% H; T5= 35% CRH +55% TC+10% H; T6= 15% CRH + 75% TC + 10% H; T7= 90% TC + 10% H. As mudas foram produzidas em bandejas de poliestireno expandido de 200 células e, aos 35 dias após a semeadura, foram avaliadas. O substrato com maior proporção de CRH (T2 with 90% CRH) teve densidade seca (DD) e porosidade total (TP) adequadas, altos pH e espaço de aeração (AS) e baixos água facilmente disponível (EAW), condutividade elétrica (EC) e teor de nutrientes, constituindo-se em um substrato inerte, não sendo indicado como substrato devido ao menor desenvolvimento das mudas. A partir de 15% de TC houve um aumento na DD, AEW, EC e nutrientes e redução na TP, AS e pH devido principalmente ao tamanho e composição das partículas do composto de tungue, que se acomodaram e alteraram as características físicas e químicas dos substratos. Substratos com 90% e 75% de TC (T7 e T6) proporcionaram o maior comprimento da parte aérea, massa fresca e seca da parte aérea e área foliar na mudas de alface, devido ao maior teor de nutrientes, aliado as características físicas e químicas desses substratos. A CRH pura não é indicada para uso como substrato, mas em mistura com o composto de tungue (T6) proporcionou a obtenção de mudas de qualidade. O composto de tungue foi eficiente em produzir mudas de alface, desde que a compostagem seja realizada de forma correta para eliminar os compostos fitotoxicos presentes neste material que poderiam prejudicar o desenvolvimento das mudas.

Zn1-xMnxO is one of the prominent materials that have attractive fundamental properties suitable for device applications that include spintronics. In the present study, aluminium co-doped Zn1-xMnxO films have been synthesized by chemical spray pyrolysis on Corning 7059 glass substrates at a constant temperature of 400 oC. The ‘Al’ composition in the layers was varied in the range, 0.0-0.07 and ‘Mn’ composition in the layers was fixed at x = 0.15. The compositional analysis shows the presence of zinc, manganese, oxygen and aluminium without any other impurities. All the films were polycrystalline and showed the hexagonal wurtzite structure of ZnO with (002) crystal plane as the preferred orientation. The film exhibited a maximum optical transmittance of > 60% and the evaluated band gap was 3.22 eV at an Al-doping level of 0.07. The highest remnant magnetization of 3.14x10-4 emu and coercive field of 464.8 Oe was observed in this study for an Al-doping of 0.07. The crystallite size, morphology, optical band gap and electrical resistivity were found to be significantly affected by changing the ‘Al’ concentration.

Here, a new, fast, and versatile method for the incorporation of colloidal quantum dots (QDs) into ionic matrices enabled by liquid-liquid diffusion is demonstrated. QDs bear a huge potential for numerous applications thanks to their unique chemical and physical properties. However, stability and processability are essential for their successful use in these applications. Incorporating QDs into a tight and chemically robust ionic matrix is one possible approach to increase both their stability and processability. With the proposed liquid-liquid diffusion-assisted crystallization (LLDC), substantially accelerated ionic crystallization of the QDs is shown, reducing the crystallization time needed by one order of magnitude. This fast process allows to incorporate even the less stable colloids including initially oil-based ligand-exchanged QDs into salt matrices. Furthermore, in a modified two-step approach, the seed-mediated LLDC provides the ability to incorporate oil-based QDs directly into ionic matrices without a prior phase transfer. Finally, making use of their processability, a proof-of-concept white light emitting diode with LLDC-based mixed QD-salt films as an excellent color-conversion layer is demonstrated. These findings suggest that the LLDC offers a robust, adaptable, and rapid technique for obtaining high quality QD-salts. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

In this work, a model-experimental feedback approach is developed and applied to fabricate high-quality, warm-white light-emitting diodes based on quantum dots (QDs) as color-conversion materials. Owing to their unique chemical and physical properties, QDs offer huge potential for lighting applications. Nevertheless, both emission stability and processability of the QDs are limited upon usage from solution. Incorporating them into a solid ionic matrix overcomes both of these drawbacks, while preserving the initial optical properties. Here borax (Na2B4O7·10H2O) is used as a host matrix because of its lower solubility and thereby reduced ionic strength in water in comparison with NaCl. This guarantees the stability of high-quality CdSe/ZnS QDs in the aqueous phase during crystallization and results in a 3.4 times higher loading amount of QDs within the borax crystals compared to NaCl. All steps from the synthesis via mixed crystal preparation to the warm-white LED preparation are verified by applying the model-experimental feedback, in which experimental data and numerical results provide feedback to each other recursively. These measures are taken to ensure a high luminous efficacy of optical radiation (LER) and a high color rendering index (CRI) of the final device as well as a correlated color temperature (CCT) comparable to an incandescent bulb. By doing so, a warm-white LED with a LER of 341 lm/Wopt, a CCT of 2720 K and a CRI of 91.1 is produced. Finally, we show that the emission stability of the QDs within the borax crystals on LEDs driven at high currents is significantly improved. These findings indicate that the proposed warm-white light-emitting diodes based on QDs-in-borax hold great promise for quality lighting. © 2015 American Chemical Society.

A large number of magnetite crystals from a fault zone — Gongchangling, China — have been studied from different point of view : grain-size distribution, crystal habit, twin morphology, natural etching features on {111}, chemical and physical properties, inclusion of other minerals, as well as microstructures of defects. A detailed statistics on the degree of departure of the crystals from a regular morphology and on the various morphological types of twins suggests a synkinematic crystallization of the magnetite under shearing stresses. This hypothesis is supported further on by the TEM observation of antiphase domains, linear dislocations, unit-cell twinnings and other defects. Decrepitation temperatures of fluid inclusions, the nature of cogenetic minerals, the etching features and δO¹⁸values all plead for a pneumatelytic origin of the magnetite connected with the magmatic activity of Proterozoic granites. This study gives the first keys to unravel the metallogenesis of the rich iron ores in Gongchangling., Un grand nombre de cristaux de magnétite issus d'une zone de faille — située à Gongchangling, Chine — ont été étudiés sous divers aspects : distribution de taille, faciès cristallin, morphologie des macles, figures naturelles d'attaque sur les faces {111}, propriétés chimiques et physiques, inclusions minérales et microstructures des défauts. Une statistique détaillée du degré de distorsion du faciès cristallin et des différents types morphologiques de macles, suggère une cristallisation syntectonique de la magnétite, sous contraintes de cisaillement. La validité de cette hypothèse est renforcée par les observations en MET de domaines antiphase, de dislocations linéaires, de maclage à l'échelle de la maille cristalline et d'autres défauts. Les températures de décrépitation des inclusions fluides, la nature des minéraux cogénétiques, les figures d'attaque ainsi que les mesures isotopiques de δO¹⁸ plaident en faveur d'une origine pneumatolitique de la magnétite liée à l'activité magmatique des granites protérozoïques. Cette étude fournit les premières clés pour comprendre la métallogenèse des riches gisements ferrifères de Gengchangling., Chen Kuang-Yuan, Sun Dai-Sheng, Wang Zu-Fu, Yang Ta-Yu, Liu Wei. The genetic significance of magnetite twins from China. In: Bulletin de Minéralogie, volume 105, 1, 1982. pp. 11-19.