In vitro and in vivo antifungal properties of silver nanoparticles against Rhizoctonia solani, a common agent of rice sheath blight disease

Sheath blight disease in rice has caused major crop losses worldwide. Managing the causal agent of disease Rhizoctonia solani Kühn is difficult because of its broad host range and formation of sclerotia which can survive in harsh environmental conditions; therefore developing innovative disease management methods without application of hazardous chemicals has been considered as the main concern to maintain sustainable agriculture. This presented research has revealed the negative impact of Silver nanoparticles (SNPs) on R. solani and disease progress both in vitro and in vivo. The adverse effects of the SNPs on R. solani are significantly dependent on the quantity of SNPs, sprayed at different concentrations in vitro. The highest inhibition level against sclerotia formation and mycelia growth are 92 and 85%, respectively, at a SNPs concentration of 50 ppm. In vivo glasshouse experiments also showed that SNPs at the same concentration favorably affects both the fresh and dry weight of rice plants with a remarkable suppressive effect on the lesion development in leaves

First report of oomycetes associated with the invasive tree Parkinsonia aculeata (Family: Fabaceae)

Phytophthora species have caused the decline and dieback of multiple tree species in Australia and around the world. Dieback in invasive trees in Australia has been observed for decades, motivating research into the potential causes of dieback to be used for biological control of these invasive species. Despite wide-ranging and ongoing research into invasive plant dieback, Phytophthora species have been largely ignored as potential causal agents of dieback, with the focus more on latent fungal pathogens living as endophytes. We conducted the first survey of Phytophthora and other oomycetes to determine their association with dieback of the invasive tree, Parkinsonia aculeata L. (Fabaceae). Using zoospore baiting, we recovered 37 oomycete isolates from roots and soil of healthy and dieback-affected P. aculeata in Kununurra, Western Australia and Charters Towers, Queensland. Using molecular taxonomy, we identified ten unique oomycete taxa, predominantly composed of Phytophthora palmivora, Ph. nicotianae and Phytopythium vexans. Parkinsonia dieback occurs across multiple climatic zones including those experiencing severe drought. We recovered fewer oomycete isolates from soil and roots in drought-affected Charters Towers than Kununurra, which had experienced recent rainfall. This may be because oomycetes require soil moisture for the dispersal of zoospores. None of the genotypes identified were consistently isolated from dieback-affected trees suggesting that any association with parkinsonia dieback may be localised. More extensive surveys and pathogenicity screenings of isolated oomycetes are required to evaluate their role in the parkinsonia dieback phenomenon

Rayleigh–Bénard convection of a viscoplastic liquid in a trapezoidal enclosure

.The objective of this paper is to clarify the role of sloping walls on convective heat transport in Rayleigh–Bénard convection within a trapezoidal enclosure filled with viscoplastic fluid. The rheology of the viscoplastic fluid has been modeled with Bingham fluid model. The system of coupled nonlinear differential equations was solved numerically by Galerkin's weighted residuals scheme of finite element method. The numerical experiments are carried out for a range of parameter values, namely, Rayleigh number (5.103 ≤ Ra ≤ 105), yield number (0 ≤ Y ≤ Yc), and sidewall inclination angle (ϕ = 0,  π/6,  π/4,  π/3) at a fixed Prandtl number (Pr = 500). Effects of the inclination angle on the flow and temperature fields are presented. The results reveal that inclination angle causes a multicellular flow and appears as the main parameter to govern heat transfer in the cavity. The heat transfer rate is found to increase with the increasing angle of the sloping wall for both Newtonian and yield stress fluids. On the other hand, the plug regions also found to increase with increasing φ, which is unusual but perhaps not unexpected behavior. In the yield stress fluids, the flow becomes motionless above a critical yield number Yc because the plug regions invade the whole cavity. The critical yield number Yc is also affected by the change of inclination angle and increases significantly with the increase of φ

OpenPNM: A Pore Network Modeling Package

Pore network modeling is a widely used technique for simulating multiphase transport in porous materials, but there are very few software options available. This work outlines the OpenPNM package that was jointly developed by several porous media research groups to help address this gap. OpenPNM is written in Python using NumPy and SciPy for most mathematical operations, thus combining Python's ease of use with the performance necessary to perform large simulations. The package assists the user with managing and interacting with all the topological, geometrical, and thermophysical data. It also includes a suite of commonly used algorithms for simulating percolation and performing transport calculations on pore networks. Most importantly, it was designed to be highly flexible to suit any application and be easily customized to include user-specified pore-scale physics models. The framework is fast, powerful, and concise. An illustrative example is included that determines the effective diffusivity through a partially water-saturated porous material with just 29 lines of code

Prenatal urban traffic noise exposure impairs spatial learning and memory and reduces glucocorticoid receptor expression in the hippocampus of male rat offspring

Introduction: Exposure to noise stress during early life may permanently affect the structure and function of the central nervous system. The aim of this study was to evaluate the effects of prenatal exposure to urban traffic noise on the spatial learning and memory of the rats' offspring and the expression of glucocorticoid receptors (GRs) in their hippocampi. Methods: Three g\roups of pregnant rats were exposed to recorded urban traffic noise for 1, 2 or 4 h/day during the last week of pregnancy. At the age of 45 days, their male offspring were introduced to the Morris water maze (MWM) for assessment of spatial learning and memory. The corticosterone levels were measured in the offspring's sera by radioimmunoassay, and the relative expression of glucocorticoid and mineralocorticoid receptors (MRs) in their hippocampi was evaluated via RT-PCR. Results: Facing urban traffic noise for 2 and 4 h/day during the third trimester of pregnancy caused the offspring to spend more time and to travel a larger distance than the controls to find the target platform. Analogously, these two groups were inferior to their control counterparts in the probe test. Also, prenatal noise stress elevated the corticosterone concentration in the sera of the rats' offspring and dose-dependently decreased the relative expression of the mRNA of both GRs and MRs in their hippocampi. Conclusions: Urban traffic noise exposure during the last trimester of pregnancy impairs spatial learning and memory of rat offspring and reduces GRs and MRs gene expression in the hippocampus

Prenatal urban traffic noise exposure impairs spatial learning and memory and reduces glucocorticoid receptor expression in the hippocampus of male rat offspring

Introduction: Exposure to noise stress during early life may permanently affect the structure and function of the central nervous system. The aim of this study was to evaluate the effects of prenatal exposure to urban traffic noise on the spatial learning and memory of the rats' offspring and the expression of glucocorticoid receptors (GRs) in their hippocampi. Methods: Three g\roups of pregnant rats were exposed to recorded urban traffic noise for 1, 2 or 4 h/day during the last week of pregnancy. At the age of 45 days, their male offspring were introduced to the Morris water maze (MWM) for assessment of spatial learning and memory. The corticosterone levels were measured in the offspring's sera by radioimmunoassay, and the relative expression of glucocorticoid and mineralocorticoid receptors (MRs) in their hippocampi was evaluated via RT-PCR. Results: Facing urban traffic noise for 2 and 4 h/day during the third trimester of pregnancy caused the offspring to spend more time and to travel a larger distance than the controls to find the target platform. Analogously, these two groups were inferior to their control counterparts in the probe test. Also, prenatal noise stress elevated the corticosterone concentration in the sera of the rats' offspring and dose-dependently decreased the relative expression of the mRNA of both GRs and MRs in their hippocampi. Conclusions: Urban traffic noise exposure during the last trimester of pregnancy impairs spatial learning and memory of rat offspring and reduces GRs and MRs gene expression in the hippocampus

Theranostic nanoparticles enhance the response of glioblastomas to radiation

YesDespite considerable progress with our understanding of glioblastoma multiforme (GBM) and the precise delivery of radiotherapy, the prognosis for GBM patients is still unfavorable with tumor recurrence due to radioresistance being a major concern. We recently developed a cross-linked iron oxide nanoparticle conjugated to azademethylcolchicine (CLIO-ICT) to target and eradicate a subpopulation of quiescent cells, glioblastoma initiating cells (GICs), which could be a reason for radioresistance and tumor relapse. The purpose of our study was to investigate if CLIO-ICT has an additive therapeutic effect to enhance the response of GBMs to ionizing radiation. Methods: NSG™ mice bearing human GBMs and C57BL/6J mice bearing murine GBMs received CLIO-ICT, radiation, or combination treatment. The mice underwent pre- and post-treatment magnetic resonance imaging (MRI) scans, bioluminescence imaging (BLI), and histological analysis. Tumor nanoparticle enhancement, tumor flux, microvessel density, GIC, and apoptosis markers were compared between different groups using a one-way ANOVA and two-tailed Mann-Whitney test. Additional NSG™ mice underwent survival analyses with Kaplan–Meier curves and a log rank (Mantel–Cox) test. Results: At 2 weeks post-treatment, BLI and MRI scans revealed significant reduction in tumor size for CLIO-ICT plus radiation treated tumors compared to monotherapy or vehicle-treated tumors. Combining CLIO-ICT with radiation therapy significantly decreased microvessel density, decreased GICs, increased caspase-3 expression, and prolonged the survival of GBM-bearing mice. CLIO-ICT delivery to GBM could be monitored with MRI. and was not significantly different before and after radiation. There was no significant caspase-3 expression in normal brain at therapeutic doses of CLIO-ICT administered. Conclusion: Our data shows additive anti-tumor effects of CLIO-ICT nanoparticles in combination with radiotherapy. The combination therapy proposed here could potentially be a clinically translatable strategy for treating GBMs

Characterization of Actinomycetes Antagonist Fusariumoxysporum f.sp.passiflora Isolated from Rhizosphere Soil ofPurple Passion Fruit Plants, South Sulawesi, Indonesia

To survey rhizosphere actinomycetes as potential biocontrol against fungal diseaseof passion fruits, rhizosphere soil of the plant were used as an isolation sources. Twenty fivestrains were assigned to Streptomyces-like strain based on morphological properties of sporechain. Four strain with distinguishing characteristic based on the macroscopic appearance ofcolonies on different media, were recovery from rhizosphere soil of passion fruits plantsuggesting that various Streptomyces spp. grow surrounding of plant roots. On an agarmedium, four strains (11.43%) commonly formed a clear growth-inhibition zone against fungal pathogen of passion fruits, Fusarium oxysporum f.sp. radicalix passiflori (FORP), indicatingthat this strains can produce antifungal substances. The present results indicate that four strainare a suitable candidate for the biocontrol of fusarium wilt. Keywords: Actinomycetes, AntifungalFusarium oxysporum f.sp.passiflora Rhizosphere, Purple Passion Fruit Plants, South Sulawesi, Indonesi