► Single phase Ni0.5Cu0.25Zn0.25Fe2−xInxO4 ferrites were synthesized by citrate–nitrate precursor auto combustion. ► Magnetic properties decreased due to the substitution of In3+ ions. ► Dielectric ...properties decreased with increase in frequency. ► This composition can be used for multilayer chip inductor (MLCI) applications.
In submitted research; nanocrystalline powders having elements Ni0.5Cu0.25Zn0.25Fe2−xInxO4 with varied amounts of indium (x=0.0, 0.1, 0.2, 0.3 and 0.4) were grown-up by modified citrate to nitrate alchemy. The realism of single phase cubic spinel creation of the synthesized ferrite samples was studied by the DTA-TGA, XRD, SEM, EDX, FT-IR, VSM and dielectric measurements. SEM was applied to inspect the morphological variations and EDX was used to determine the compositional mass ratios. The studies on the dielectric constant (ε′), dielectric loss (ε″), loss tangent (tanδ), ac conductivity (σac), resistive and reactive parts of the impedance analysis (Z’ and Z”) at room temperature were also carried out. The saturation magnetizations (Ms) were determined using the vibrating sample magnetometer (VSM). Ms. decreased with the increase In3+ doping content, as Fe3+ of 5μB ions are replaced by In3+ of 0μB ions.
•Optical band gap of bulk iron oxide powder has been tailored using pulse laser ablation.•Crystalline size dependent optical and magnetic properties have been studied.•In the present study it is ...shown that strain depends on crystalline size and different phases of iron oxide NPs.
Iron oxide (Fe2O3) bulk powder have been ablated/fragmented in different liquid medium by Nd:YAG laser beam using 1064nm wavelength. Sodium dodecyl sulfate (SDS), cetyltrimethyl ammonium bromide (CTAB) and double distilled water (DDW) are used as liquid medium. Crystalline size, lattice strain, phase and structure of ablated particles have been investigated using synchrotron X-ray diffraction. Optical band gap energy of as purchased Fe2O3 found 1.92eV that increased to 2.03eV after ablation in CTAB determined by UV–vis absorption spectroscopy. Magnetic properties have been analyzed by hysteresis loops using vibrating sample magnetometer (VSM). Crystalline sizes have been found in the range of 29.23–16.54nm and coercivity tailored in the range of 206.91–298.36Oe using laser ablation. Saturation magnetization and remanence have been found in the range of 0.013–3.41emu/g and 0.0023–.0.51emu/g respectively. Particle shape and size have been examined by scanning electron microscopy (SEM). CTAB (cationic) and SDS (anionic) surfactants are used as capping agent. CTAB produces phase transformation in ablated iron oxide (Fe2O3). Crystallinity and crystalline size of ablated particles in DDW increased due to presence of rich oxygen in it due to oxidation. Ablated Fe2O3 nanoparticles have been widely used experimentally for numerous in vivo applications such as MRI contrast enhancement agent, tissue repair, immunoassay, detoxification of biological fluids, hyperthermia, drug delivery and cell separation.
The disaccharide trehalose and trehalose-6-phosphate that are present in trace amounts are suggested to have a signaling function in plants. Recently, it was demonstrated that trehalose metabolism ...contributes to Arabidopsis thaliana defense against the green peach aphid (GPA; Myzus persicae Sülzer), an important insect pest of a large variety of plants. TPS11 (TREHALOSE PHOSPHATE SYNTHASE11)-dependent trehalose metabolism was shown to curtail GPA infestation by promoting starch accumulation and expression of the PAD4 (PHYTOALEXIN-DEFICIENT4) gene, which has important roles in regulating antibiosis and antixenosis against GPA. Here we show that trehalose metabolism is similarly activated in leaves of GPA-infested tomato (Solanum lycopersicum) plants and likely contributes to tomato defense against GPA. GPA-infested leaves of tomato accumulated trehalose, which was accompanied by the transient upregulation of SlTPS11, a homolog of the Arabidopsis TPS11. GPA-infestation was also accompanied by starch accumulation and the upregulation of SlPAD4, the tomato homolog of Arabidopsis PAD4. Furthermore, trehalose application induced SlPAD4 expression and starch accumulation, and curtailed GPA infestation, suggesting that like in Arabidopsis trehalose contributes to tomato defense against GPA.
Fusarium graminearum causes Fusarium head blight, an important disease of wheat. F. graminearum can also cause disease in Arabidopsis thaliana. Here, we show that the Arabidopsis LOX1 and LOX5 genes, ...which encode 9-lipoxygenases (9-LOXs), are targeted during this interaction to facilitate infection. LOX1 and LOX5 expression were upregulated in F. graminearum-inoculated plants and loss of LOX1 or LOX5 function resulted in enhanced disease resistance in the corresponding mutant plants. The enhanced resistance to F. graminearum infection in the lox1 and lox5 mutants was accompanied by more robust induction of salicylic acid (SA) accumulation and signaling and attenuation of jasmonic acid (JA) signaling in response to infection. The lox1- and lox5-conferred resistance was diminished in plants expressing the SA-degrading salicylate hydroxylase or by the application of methyl-JA. Results presented here suggest that plant 9-LOXs are engaged during infection to control the balance between SA and JA signaling to facilitate infection. Furthermore, since silencing of TaLpx-1 encoding a 9-LOX with homology to LOX1 and LOX5, resulted in enhanced resistance against F. graminearum in wheat, we suggest that 9-LOXs have a conserved role as susceptibility factors in disease caused by this important fungus in Arabidopsis and wheat.
Localized infection in plants often induces systemic acquired resistance (SAR), which provides long-term protection against subsequent infections. A signal originating in the SAR-inducing organ is ...transported to the distal organs, where it stimulates salicylic acid (SA) accumulation and priming, a mechanism that results in more robust activation of defenses in response to subsequent pathogen infection. In recent years, several metabolites that promote long-distance SAR signaling have been identified. However, the mechanism or mechanisms by which plants perceive and respond to the SAR signals are largely obscure. Here, we show that, in Arabidopsis thaliana, the FLOWERING LOCUS D (FLD) is required for responding to the SAR signals leading to the systemic accumulation of SA and enhancement of disease resistance. Although the fld mutant was competent in accumulating the SAR-inducing signal, it was unable to respond to the SAR signal that accumulates in petiole exudates of wild-type leaves inoculated with a SAR-inducing pathogen. Supporting FLD's role in systemic SAR signaling, we observed that dehydroabietinal and azelaic acid, two metabolites that, in wild-type plants, promote SAR-associated systemic accumulation of SA and priming, respectively, were unable to promote SAR in the fld mutant. FLD also participates in flowering, where it functions to repress expression of the flowering repressor FLOWERING LOCUS C (FLC). However, epistasis analysis indicates that FLD's function in SAR is independent of FLC.
Fusarium graminearum is the principal causative agent of Fusarium head blight (FHB), a devastating disease of wheat and barley. This fungus can also colonize Arabidopsis thaliana. Disease resistance ...was enhanced in transgenic wheat and Arabidopsis plants that constitutively overexpress the NONEXPRESSOR OF PATHOGENESIS-RELATED GENES 1 (NPR1) gene, which regulates salicylic acid (SA) signaling and modulates the activation of jasmonic acid (JA)-dependent defenses. Here, we provide several lines of evidence that reveal an important role for SA and JA signaling in Arabidopsis defense against F. graminearum. SA level was elevated in fungus-inoculated leaves, and SA application and biologically activated systemic acquired resistance enhanced resistance. Furthermore, the disruption of SA accumulation and signaling in the sid2 mutant and NahG transgenic plant, and the npr1 and wrky18 mutants, respectively, resulted in heightened susceptibility to this fungus in leaves and inflorescence. JA signaling was activated in parallel with SA signaling in the fungus-challenged plants. However, the hyperresistance of the JA pathway mutants opr3, coi1, and jar1 indicates that this pathway contributes to susceptibility. Genetic and biochemical experiments indicate that the JA pathway promotes disease by attenuating the activation of SA signaling in fungus-inoculated plants. However, the hypersusceptibility of the jar1 npr1 double mutant compared with the npr1 mutant suggests that JAR1 also contributes to defense, signifying a dichotomous role of JA and a JAR1-dependent mechanism in this interaction.
Merck & Co, Inc (Kenilworth, NJ) is investing in approaches to enrich clinical trial data and augment decision making through use of digital health technologies, outpatient sampling, and real‐time ...data access. As part of this strategy, a phase I study was conducted to explore a few technologies of interest. In this fixed‐sequence two‐period trial, 16 healthy subjects were administered 50‐mg once‐daily sitagliptin packaged in a bottle that electronically captured the date and time study medication was dispensed (period 1) and in a traditional pharmacy bottle (period 2). Dried blood spot samples were collected for sitagliptin concentration analysis on select study days, both in clinic and at home, with collection time recorded using an electronic diary in period 1 and by clinic staff in period 2. Study results demonstrated the feasibility and subject acceptance of collecting digital adherence data and outpatient dried blood spot samples in clinical trials and highlighted areas for future improvements.
Fusarium head blight (FHB) is a devastating disease of wheat and barley which causes extensive losses worldwide. Monogenic, gene-for-gene resistance to FHB has not been reported. The best source of ...resistance to FHB is a complex, quantitative trait derived from the wheat cv. Sumai 3. Here, we show that the Arabidopsis thaliana NPR1 gene (AtNPR1), which regulates the activation of systemic acquired resistance, when expressed in the FHB-susceptible wheat cv. Bobwhite, confers a heritable, type II resistance to FHB caused by Fusarium graminearum. The heightened FHB resistance in the transgenic AtNPR1-expressing wheat is associated with the faster activation of defense response when challenged by the fungus. PR1 expression is induced rapidly to a high level in the fungus-challenged spikes of the AtNPR1-expressing wheat. Furthermore, benzothiadiazole, a functional analog of salicylic acid, induced PR1 expression faster and to a higher level in the AtNPR1-expressing wheat than in the nontransgenic plants. We suggest that FHB resistance in the AtNPR1-expressing wheat is a result of these plants being more responsive to an endogenous activator of plant defense. Our results demonstrate that NPR1 is an effective candidate for controlling FHB.
Direct infusion electrospray ionization triple quadrupole precursor scanning for three oxidized fatty acyl anions revealed 86 mass spectral peaks representing polar membrane lipids in extracts from ...Arabidopsis (Arabidopsis thaliana) infected with Pseudomonas syringae ñ í tomato DC3000 expressing AvrRpt2 (PstAvr). Quadrupole time-of-flight and Fourier transform ion cyclotron resonance mass spectrometry provided evidence for the presence of membrane lipids containing one or more oxidized acyl chains. The membrane lipids included molecular species of phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, digalactosyldiacylglycerol, monogalactosyldiacylglycerol, and acylated monogalactosyldiacylglycerol.The oxidized chains were identified at the level of chemical formula and included Cⁱɸ H⁷ O (abbreviated 18:4-O, to indicate four double bond equivalents and one oxygen beyond the carbonyl group),CⁱɸH⁹ O (18:3-O), CⁱɸHⁱ O (18:2-O), CⁱɸH⁹O⁴(18:3-2O),CⁱɸHⁱO⁴(18:2-2O), and Cⁱ⁶HO (16:4-O). Mass spectral signals from the polar oxidized lipid (ox-lipid) species were quantified in extracts of Arabidopsis leaves subjected to wounding, infection by PstAvr, infection by a virulent strain of P.syringae, and low temperature. Ox-lipids produced low amounts of mass spectral signal, 0.1% to 3.2% as much as obtained in typical direct infusion profiling of normal-chain membrane lipids of the same classes. Analysis of the oxidized membrane lipid species and normal-chain phosphatidic acids indicated that stress-induced ox-lipid composition differs from the basal ox-lipid composition. Additionally, different stresses result in the production of varied amounts, different timing, and different compositional patterns of stress-induced membrane lipids. These data form the basis for a working hypothesis that the stressspecific signatures of ox-lipids, like those of oxylipins, are indicative of their functions.
•Plant defense against aphids, which are phloem sap-consuming pests of plants and vectors of diseases, is reviewed here.•A conglomerate of defenses that impact aphid behavior, growth, survival and ...reproduction are exerted at multiple steps during infestation.•The effector function as well as defense elicitor role of proteins present in aphid saliva is beginning to be recognized.•Host defense against aphids is modulated by viruses they transmit.•Plants have also evolved compensatory mechanisms that allow them to tolerate aphid infestation.
Aphids are amongst the most damaging pests of plants that use their stylets to penetrate the plant tissue to consume large amounts of phloem sap and thus deprive the plant of photoassimilates. In addition, some aphids vector important viral diseases of plants. Plant defenses targeting aphids are broadly classified as antibiosis, which interferes with aphid growth, survival and fecundity, and antixenosis, which influences aphid behavior, including plant choice and feeding from the sieve elements. Here we review the multitude of steps in the infestation process where these defenses can be exerted and highlight the progress made on identifying molecular factors and mechanisms that contribute to host defense, including plant resistance genes and signaling components, as well as aphid-derived effectors that elicit or attenuate host defenses. Also discussed is the impact of aphid-vectored plant viruses on plant-aphid interaction and the concept of tolerance, which allows plant to withstand or recover from damage resulting from the infestation.