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s " Trichoderma and Pseudomonas strains were isolated from cucumber rhizosphere. " Strains were tested for eliciting systemic resistance against Fusarium in cucumber. " Combining Trichoderma and Pseudomonas leads to enhanced induced resistance. " This enhanced effectiveness is observed in cucumber but not in Arabidopsis. " In cucumber the enhanced effectiveness is paralleled by enhanced priming of defense genes.

Magnetic techniques are suitable to detect iron oxides even in trace concentrations. However, since several iron oxides may be simultaneously present in natural and synthetic samples, mixtures of magnetic particles and magnetic interactions between grains can complicate magnetic signatures. Among the iron oxide minerals, hematite (α-Fe2O3) and magnetite (Fe3O4) are the most common. In this work, different commercial hematite powders, normally used as Fe precursor in laboratory synthesis of Fe-containing oxides, were characterized using X-ray diffractometry (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometry (VSM). The effects of different concentrations of the hematite and magnetite on the magnetic properties of a set of mixtures (from 1 to 10 wt% magnetite) were then investigated by measuring the hysteresis loops, first order reversal curves (FORCs), thermal demagnetization, and isothermal remanent magnetization (IRM) curves. The three commercial hematite powders presented different magnetic behaviors mostly due to the effects of particle size. The magnetic results of mixtures reveal that it is very difficult to identify hematite magnetic signals by means of hysteresis loops, FORCs, or thermal demagnetization when even a small amount of magnetite (>5 wt%) is present due to magnetite’s high specific magnetization. However, IRM was found to be a sensitive method to determine the presence of hematite when magnetite is simultaneously present as high as 10 wt%.

In this study, the treatment of pistachio nuts by Bacillus subtilis UTBSP1, a promising isolate to degrade aflatoxin B1 (AFB1), caused to reduce the growth of Aspergillus flavus R5 and AFB1 content on pistachio nuts. Fluorescence probes revealed that the cell free supernatant fluid from UTBSP1 affects spore viability considerably. Using high-performance liquid chromatographic (HPLC) method, 10 fractions were separated and collected from methanol extract of cell free supernatant fluid. Two fractions showed inhibition zones against A. flavus. Mass spectrometric analysis of the both antifungal fractions revealed a high similarity between these anti-A. flavus compounds and cyclic-lipopeptides of surfactin, and fengycin families. Coproduction of surfactin and fengycin acted in a synergistic manner and consequently caused a strong antifungal activity against A. flavus R5. There was a positive significant correlation between the reduction of A. flavus growth and the reduction of AFB1 contamination on pistachio nut by UTBSP1. The results indicated that fengycin and surfactin-producing B. subtilis UTBSP1 can potentially reduce A. flavus growth and AFB1 content in pistachio nut.

Although natural materials are the subject of most Earth science articles, fundamental studies on analogous synthetic materials, produced under laboratory‐controlled conditions, can provide significant insight into expected behavior of natural systems. Iron, a common element in natural aluminosilicates as well as high‐level nuclear wastes, plays a crucial role in crystallization behavior. In the present study, effects of Fe‐Al substitution in nepheline‐based aluminosilicate glasses (NaAl(1 − x)FexSiO4, x = 0.0–1.0) were investigated to assess the role of iron in crystallization, employing semiquantitative X‐ray diffraction (XRD), vibrating sample magnetometry (VSM), and electron probe microanalysis (EPMA). Fe promotes nepheline crystallization when substituted for Al in low additions (x < 0.3), yet suppresses it at higher additions (x > 0.5). Since effect of Fe is the subject of the present work and is the most common magnetic element, magnetic techniques were used to further analyze the phase assemblage. VSM measurements revealed that Fe oxides, i.e., hematite and magnetite, are present in cases even when their fractions are below the XRD detection limit, and backscattered electron micrographs confirm their presence. EPMA also shows that Fe incorporation in nepheline increases with increasing Fe‐Al substitution, up to a maximum of x = 0.37 for the nepheline crystals in the sample with starting glass of Na(Al0.3Fe0.7)SiO4. The residual glass, on the other hand, contains approximately constant Fe concentration x ~ 0.54–0.59 for all samples with starting Fe addition 0.4 ≤ x ≤ 0.8, and excess iron is expelled into Fe oxide phases. The significance of these results for geological processes and immobilization of high‐level nuclear waste is discussed.

Sintered thermoelectric (TE) nanoparticle films are known to have a high figure-of-merit ZT factor and are considered for waste hear recovery and heating and cooling applications. The conventional process of thermal sintering of TE nanoparticles requires an inert environment and long heating times, and cannot be used on polymer substrates due to the requirements of the process (e.g., heating up to 400 C). In this communication, the authors demonstrate for the first time the use of an intense flash of UV light from a Xenon lamp to sinter TE nanoparticles within milliseconds under ambient conditions on flexible polymer as well as glass substrates to create functional TE films. Photonic sintering is used to fabricate Bismuth Telluride thermoelectric films with a conductivity of 3200 S m À1 (a 5-6 orders of magnitude increase over unsintered films) and a peak power factor of 30 mW m À1 K À2 . Modeling is used to gain an insight into the physical processes occurring during photonic sintering process and identify the critical parameters controlling the process. This work opens-up an exciting possibility of extremely rapid fabrication of TE generators under ambient conditions on a variety of flexible and rigid substrates.Thermoelectric generators based on the Seebeck effect have shown a great promise for waste heat recovery in diverse applications such as automotive engines, power plants, and microelectronics. [1] Thermoelectric devices have also been considered for heating and cooling applications. [2] The efficiency of thermoelectric materials is determined by the figure-of-merit ZT which is defined by ZT ¼ α 2 σT/κ, where α, σ, κ, and Tare Seebeck coefficient, electrical conductivity, thermal conductivity, and absolute temperature, respectively. The ZT factor of TE generators can be significantly enhanced by making nanostructured TE materials using nanoparticles due to the reduction in lattice thermal conductivity. [3] High performance TE films have been demonstrated by printing nanoparticles followed by thermal sintering at around 400 C in an inert environment. [4] However, the conventional sintering methods such as thermal sintering in a furnace suffer from two major limitations. First, the process of thermal sintering can take several hours per batch and is unsuitable for rapid fabrication methods such as roll-to-roll manufacturing [5] of TE generators. Second, the conventional thermal sintering exposes both the printed film and substrate to high temperatures, which limits the type of substrate that can be used to form the films.To overcome these challenges, we demonstrate in this work the use of photonic sintering method [6,7] to create TE films from Bismuth Telluride-based nanoparticles where sintering/densification is achieved over large areas (several square inches), in extremely short periods of time (milliseconds per pulse) and using a rigid glass as well as flexible polymer substrate. Due to the high speed of sintering, this method is highly compatible with rapid roll-to-roll manufacturing of low-cost

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