337 research outputs found

    Thrips-tospovirus interactions: biological and molecular implications

    Get PDF
    The occurrence of thrips vectors in considerable numbers enables their functioning in a dual role as vectors and as direct crop pests. The resistance of thrips to pesticides has enabled quick transmission of viruses, the transient nature of their populations being essentially responsible for the infection. The feeding behaviour of thrips contributes in a large measure towards their ability to act as vectors, enabling leaf-to-leaf transmission of the tospoviruses. The specific association of the tospoviruses and thrips vectors, particularly relating to the molecular profiles, needs increasing scrutiny to come to proper conclusions. A better understanding of the nature of virus multiplication and the pathways leading to their entry into the salivary glands and the ability of the second instar larvae to inoculate plants need further inputs. The intraspecific diversity of thrips vectors as a result of population studies from various parts of the country, would further enable a better understanding of the ability of each species to transfer the virus, besides better appreciation of the chemical ecology of thrips-host-plant interaction, not to mention the relevance of serodiagnosis in detecting disease or health

    Kairomones of Heliothis armigera and Corcyra cephalonica and their influence on the parasitic potential of Trichogramma chilonis (Trichogrammatidae: Hymenoptera)

    Get PDF
    Kairomones from moth scales tend to influence the parasitic potential byTrichogramma chilonis Ishii. Hexatriacontane, pentacosane, heptadecane, docosane and 2, 6, l0-dodecatrienal-3, 7, 11-trimethyl were identified from the active moth scale extract ofHeliothis armigera Hubner (its natural host) andCorcyra cephalonica Stainton (a laboratory host). The significance of an array of compounds from moth scales with kairomonal activity for manipulating entomophagous insects in biological control programmes is discussed

    Modeling Camera Effects to Improve Visual Learning from Synthetic Data

    Full text link
    Recent work has focused on generating synthetic imagery to increase the size and variability of training data for learning visual tasks in urban scenes. This includes increasing the occurrence of occlusions or varying environmental and weather effects. However, few have addressed modeling variation in the sensor domain. Sensor effects can degrade real images, limiting generalizability of network performance on visual tasks trained on synthetic data and tested in real environments. This paper proposes an efficient, automatic, physically-based augmentation pipeline to vary sensor effects --chromatic aberration, blur, exposure, noise, and color cast-- for synthetic imagery. In particular, this paper illustrates that augmenting synthetic training datasets with the proposed pipeline reduces the domain gap between synthetic and real domains for the task of object detection in urban driving scenes

    Linear and non-linear regression analysis for the sorption kinetics of Rhodamine dye from aqueous solution using Chitosan-Jackfruit nanocomposite

    Get PDF
    This paper presents experimental results such as the adsorbate-adsorbent chemical properties and chemical interaction as well as adsorption conditions. The experimental results were fitted to batch kinetic studies to obtain the characteristic parameters of each model. According to the evaluation using the Kinetic equation, the maximum sorption capacity at dye concentration was 19.6 (mg g-1), pH 11.6 (mg g-1) and temperature 24.2 (mg g-1) Rhodamine dye were investigated. For all of the systems studied, the pseudo-first-order and pseudo-second-order model provided the best correlation of the kinetic experimental data. The results revealed that with increasing temperature and decreasing pH, ionic strength, and adsorbate concentration, dye removal efficiency has increased. Chitosan-Jackfruit nanocomposite could remove 90.2% dye from the solution containing 40 mg/L dye at 100 min. The results indicated that dye removal followed pseudo-second-order kinetic (R2>0.99). According to the findings, Chitosan-Jackfruit nanocomposites an effective adsorbent for direct dye removal from wastewater

    Synthesis of Iron Oxide Magnetic Nanoparticles: Characterization and its Biomedical Application

    Get PDF
    In the present time, Iron oxide magnetic nanoparticles (IOMNPs) have paid considerable attention due to their exclusive applications in terms of surface-to-volume ratio, superparamagnetism, high surface area, biosensor, bio-separation, catalysis, and biomedicine. Our goal was to synthesis iron oxide magnetic nanoparticles by chemical route technique. The preparation method had a very large effect on the size, shape, and surface chemistry of the magnetic nanoparticles including their applications. The iron chloride solution was prepared by mixing deionized water with iron chloride tetrahydrate. The synthesized powder was characterized by XRD, UV-vis, SEM, FT-IR, DLS, FL, and TGA techniques. Moreover, antibacterial activity was evaluated using the synthesized IOMNPs against Escherichia coli (A), Pseudomonas (B), Enterobacter (C), Staphylococcus aureus (D), and Bacillus subtilis (E) in the concentration of 0.1 mg and 0.5 mg. The results showed that Bacillus subtilis possess a higher antibacterial activity at the concentration of 0.5 mg comparing the other bacterial species. The outcome of this work would contribute to the present understanding of the biomedical application with the obtained size, shape, and synthesized method

    Green Synthesis and Characterization of Antibacterial Studies by Iron Oxide Nanoparticles using Carica papaya Leaf Extract

    Get PDF
    In present years, the synthesis of iron oxide nanoparticles (IONPs) has established excessive potential in biological applications due to their non-toxic role in biological systems, biocompatibility, and biodegradability. Ongoing research efforts focused on IONPs in the expansion of novel technologies as they can be synthesized with surface modification. Here we have studied the antibacterial effects of IONPs which were synthesized effectively through a green synthesis route by using leaf extract of the Carica papaya plant. The formation of IONPs was confirmed by the color change. The crystallinity of IONPs was determined by XRD and the morphology by using SEM, which showed spherical particles of well-dispersed size. The absorption peak was determined by UV–vis spectroscopy at 390 nm. Average particle size distribution was obtained at 56 nm using PSA.  FL spectroscopy indicated the higher emission wavelength by redshift at 641.6 nm. TGA showed that the IONPs are thermally stable up to 200⁰C with no decomposition. The outcome would pave a way for utilizing IONPs for better biomedical application

    AEROBIOLOGY OF MULBERRY FIELDS IN VELLORE DISTRICT

    Get PDF
    ABSTRACT Mulberry which forms the exclusive source of food for commercial silk producing silk worm (Bombyx mori L.) is affected by a number of diseases and pests. The aerobiology of crop field was very limited and much of the fields were to be opened for investigation. It affects the nutrition, growth and cocoon production of silkworm. Hence a detailed investigation was carried out on the aerobiology of mulberry fields in Vellore district. The Vellore district comprises of eight taluks, 14 ranges and 64 subdivisions. Much of the Vellore district land area is cultivated by Mulberry as a cottage industry. It is found that from October to January rainfall was maximum, Vaniyambadi, Tirupattur and Gudiyattam receives maximum rain. The humidity is relatively maximum during the period of October to September 1999. The temperature was maximum from March to June. This helps for the spread and growth of various microflora and airspores in Vellore district environs. From these data, the causative organisms of various diseases of Mulberry were identified. This data will be helpful for the treatment, management of the much useful plant Mulberry in Vellore district

    Metabolic Disorder Dysfunction in Parkinson’s Disease: Bioenergetics, Redox Homeostasis and Central Carbon Metabolism

    Get PDF
    The loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and the accumulation of protein inclusions (Lewy bodies) are the pathological hallmarks of Parkinson’s disease (PD). PD is triggered by genetic alterations, environmental/occupational exposures and aging. However, the exact molecular mechanisms linking these PD risk factors to neuronal dysfunction are still unclear. Alterations in redox homeostasis and bioenergetics (energy failure) are thought to be central components of neurodegeneration that contribute to the impairment of important homeostatic processes in dopaminergic cells such as protein quality control mechanisms, neurotransmitter release/metabolism, axonal transport of vesicles and cell survival. Importantly, both bioenergetics and redox homeostasis are coupled to neuro-glial central carbon metabolism. We and others have recently established a link between the alterations in central carbon metabolism induced by PD risk factors, redox homeostasis and bioenergetics and their contribution to the survival/death of dopaminergic cells. In this review, we focus on the link between metabolic dysfunction, energy failure and redox imbalance in PD, making an emphasis in the contribution of central carbon (glucose) metabolism. The evidence summarized here strongly supports the consideration of PD as a disorder of cell metabolism

    Synthesis and Characterization of Silver Nanoparticles from Ashyranthus aspera Extract for Antimicrobial Activity Studies

    Get PDF
    Development of biologically inspired experimental processes for the synthesis of nanoparticles is evolving into an important branch of nanotechnology. Plant-mediated synthesis of nanomaterials has been increasingly gaining popularity due to its eco-friendly nature and cost-effectiveness. In the present study, we were synthesized silver (Ag) nanoparticles using aqueous extracts of fresh leaves of Ashyranthus aspera medicinal plants as bio-reducing agents. UV-Vis spectrometer used to monitor the reduction of Ag ions and the formation of AgNPs in the medium. UV-Vis spectra and visual observation showed that the color of the fresh leaf extracts of Ashyranthus aspera turned into grayish-brown respectively, after treatment with Ag precursors. XRD and SEM have been used to investigate the morphology of prepared AgNPs. The peaks in the XRD pattern are associated with that of the Face-Centered-Cubic (FCC) form of metallic silver. TGA/DTA results associated with weight loss and exothermic reaction due to the desorption of chemisorbed water. FTIR was performed to identify the functional groups which form a layer covering AgNPs and stabilize the AgNPs in the medium. Moreover, silver nanoparticles using aqueous leaf extracts of Ashyranthus aspera were separately tested for their antibacterial activity against Gram-positive bacteria ( Staphylococcus aureus ) and Gram-negative bacteria ( Enterobacter ). The results showed that the bacterial growth was inhibited by the extracts containing AgNPs Nanoparticles. The biosynthesized nanoparticle was prepared from Ashyranthus aspera leaf extracts exhibits potential applications as broad-spectrum antimicrobial agents

    Character and spatial distribution of OH/H<SUB>2</SUB>O on the surface of the moon seen by M<SUP>3</SUP> on Chandrayaan-1

    Get PDF
    The search for water on the surface of the anhydrous Moon had remained an unfulfilled quest for 40 years. However, the Moon Mineralogy Mapper (M3) on Chandrayaan-1 has recently detected absorption features near 2.8 to 3.0 micrometers on the surface of the Moon. For silicate bodies, such features are typically attributed to hydroxyl- and/or water-bearing materials. On the Moon, the feature is seen as a widely distributed absorption that appears strongest at cooler high latitudes and at several fresh feldspathic craters. The general lack of correlation of this feature in sunlit M3 data with neutron spectrometer hydrogen abundance data suggests that the formation and retention of hydroxyl and water are ongoing surficial processes. Hydroxyl/water production processes may feed polar cold traps and make the lunar regolith a candidate source of volatiles for human exploration
    corecore