High‐Performance and Stable Perovskite Solar Cells Based on Dopant‐Free Arylamine‐Substituted Copper(II) Phthalocyanine Hole‐Transporting Materials

A power conversion efficiency (PCE) as high as 19.7% is achieved using a novel, low‐cost, dopant‐free hole transport material (HTM) in mixed‐ion solution‐processed perovskite solar cells (PSCs). Following a rational molecular design strategy, arylamine‐substituted copper(II) phthalocyanine (CuPc) derivatives are selected as HTMs, reaching the highest PCE ever reported for PSCs employing dopant‐free HTMs. The intrinsic thermal and chemical properties of dopant‐free CuPcs result in PSCs with a long‐term stability outperforming that of the benchmark doped 2,2′,7,7′‐Tetrakis‐(N,N‐di‐p‐methoxyphenylamine)‐9,9′‐Spirobifluorene (Spiro‐OMeTAD)‐based devices. The combination of molecular modeling, synthesis, and full experimental characterization sheds light on the nanostructure and molecular aggregation of arylamine‐substituted CuPc compounds, providing a link between molecular structure and device properties. These results reveal the potential of engineering CuPc derivatives as dopant‐free HTMs to fabricate cost‐effective and highly efficient PSCs with long‐term stability, and pave the way to their commercial‐scale manufacturing. More generally, this case demonstrates how an integrated approach based on rational design and computational modeling can guide and anticipate the synthesis of new classes of materials to achieve specific functions in complex device structures.     

Vertical Redistribution of Soil Organic Carbon Pools After Twenty Years of Nitrogen Addition in Two Temperate Coniferous Forests

Nitrogen (N) inputs from atmospheric deposition can increase soil organic carbon (SOC) storage in temperate and boreal forests, thereby mitigating the adverse effects of anthropogenic CO₂ emissions on global climate. However, direct evidence of N-induced SOC sequestration from low-dose, long-term N addition experiments (that is, addition of < 50 kg N ha⁻¹ y⁻¹ for > 10 years) is scarce worldwide and virtually absent for European temperate forests. Here, we examine how tree growth, fine roots, physicochemical soil properties as well as pools of SOC and soil total N responded to 20 years of regular, low-dose N addition in two European coniferous forests in Switzerland and Denmark. At the Swiss site, the addition of 22 kg N ha⁻¹ y⁻¹ (or 1.3 times throughfall deposition) stimulated tree growth, but decreased soil pH and exchangeable calcium. At the Danish site, the addition of 35 kg N ha⁻¹ y⁻¹ (1.5 times throughfall deposition) impaired tree growth, increased fine root biomass and led to an accumulation of N in several belowground pools. At both sites, elevated N inputs increased SOC pools in the moderately decomposed organic horizons, but decreased them in the mineral topsoil. Hence, long-term N addition led to a vertical redistribution of SOC pools, whereas overall SOC storage within 30 cm depth was unaffected. Our results imply that an N-induced shift of SOC from older, mineral-associated pools to younger, unprotected pools might foster the vulnerability of SOC in temperate coniferous forest soils.

     

Noemi Controls Production of Flavonoid Pigments and Fruit Acidity and Illustrates the Domestication Routes of Modern Citrus Varieties

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Endophytes from wild cereals protect wheat plants from drought by alteration of physiological responses of the plants to water stress

Endophytes contribute to plant performance, especially under harsh conditions. We therefore hypothesized that wild plants have retained beneficial endophytes that are less abundant or not present in related crop plants. To test this hypothesis, we selected two endophytes that were found in Sharon goatgrass, an ancestor of wheat, and tested their effect on bread wheat. Both endophytes infected wheat and improved sustainability and performance under water-limited conditions. To determine how the endophytes modify plant development, we measured parameters of plant growth and physiological status and performed a comparative metabolomics analysis. Endophyte-treated wheat plants had reduced levels of stress damage markers and reduced accumulation of stress-adaptation metabolites. Metabolomics profiling revealed significant differences in the response to water stress of endophyte-treated plants compared with untreated plants. Our results demonstrate the potential of endophytes from wild plants for improvement of related crops and show that the beneficial effects of two endophytes are associated with alteration of physiological responses to water-limited conditions.     

Precise Gene Editing Preserves Hematopoietic Stem Cell Function following Transient p53-Mediated DNA Damage Response

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In vitro interaction between ceftazidime and vancomycin/teicoplanin in the presence of azithromycin againstPseudomonas aeruginosa

Pseudomonas aeruginosa is an opportunistic pathogen, intrinsically resistant to many antibiotics and prone to acquire resistance against many drugs. It is assumed that agents that disorganise the structure of the outer membrane might allow the passage of other drugs into cell. To verify this hypothesis, ceftazidime (CAZ) has been tested in association with glycopeptides (GLYs) and azithromycin (AZI). Time-kill experiments were performed on a representative strain. CAZ in combination with GLYs showed 99, 90 and 10% of CFU/ml reduction in 33.9,52.5 and 13.6% of the cases, respectively; the addition of AZI increased the incidence of 99% CFU/ml reduction to 42% of the cases. Indifference was the most common finding, and additive/synergism in the other cases. Present findings demonstrated that CAZ favourably reacted with GLYs in the presence of AZI.     

Overexpression of sialidase NEU3 increases the cellular radioresistance potential of U87MG glioblastoma cells

The plasma membrane-associated sialidase NEU3 is known to play important roles in different physiological and pathophysiological processes such as proliferation, cellular differentiation and tumorigenesis. Up-regulation of NEU3 has been associated to several tumors and recently it was demonstrated that its down-modulation in glioblastoma cells promotes cell invasiveness. To date, no information concerning the possible role played by NEU3 in relation to tumor radioresistance is available. Here we show that overexpression of NEU3 in glioblastoma U87MG cells activates PI3K/Akt signaling pathway resulting in an increased radioresistance capacity and in an improved efficiency of double strand DNA-repair mechanisms after irradiation. Our results demonstrate for the first time that NEU3 contributes to the radioresistance features of U87MG cells, bringing to evidence a novel rand peculiar role of the enzyme in cancer biology.     

In silico and in vivo analysis of ABI3 and VAL2 genes during somatic embryogenesis of Coffea arabica: competence acquisition and developmental marker genes

Plant Cell, Tissue and Organ Culture (PCTOC) - The employment of biotechnology-based approaches such as somatic embryogenesis has been applied to several plants including Coffea sp. Despite the...