THE CONTROL OF BACTERIAL BLIGHT OF POMEGRANATE USING THE METHANOLIC EXTRACTS OF INDIAN BAEL AND LEUCAS ASPERA

Objectives: Blight disease occurring due to Xanthomonas axonopodis (pv. Punicae) has been creating a problem in pomegranate cultivation whose symptoms appear on leaves as well as on fruits and stem and thereby causing a detrimental effect on yield by reducing it to nearly 70–75%. In recent years, the disease has been controlled by nanoparticles (silver and copper). We are looking forward to an organic and more economic method for the control of blight disease of pomegranate which is farmer and consumer friendly. Methods: In the present work, the causative agent of disease was isolated from the infected pomegranate fruit which was collected from Bellary, Karnataka on nutrient agar media using streak plating method. Secondary metabolites were extracted from Leucas aspera and Indian bael using methanol as solvent from maceration and soxhlet extraction techniques for about six hours. These methods are considered as the traditional methods for extracting phenolic compounds along with the ultrasound assisted solvent extraction (UASE) method. Since UASE degrades the phenols and certain metabolites which act as nutrients we did not go for this technique. The Phytochemical screening of extracts was conducted to check the presence of secondary metabolites having antimicrobial activity. The methanolic extracts were characterised using thin layer chromatography (TLC) and Fourier transform infra-red (FTIR) spectroscopy. The antimicrobial activity for extracts of L. aspera and Indian bael were tested by agar disc diffusion method. Results: Clear Zone of Inhibition (ZOI) were observed for methanolic extracts of L. aspera (40 mg/ml and 100mg/ml) and Indian bael (160 mg/ml) which shows that the blight disease could be controlled. Conclusion: Indian bael methanolic extract (160 mg/ml) shows better control against growth of Xanthomonas species with higher ZOI values than L. aspera extracts (100 mg/ml and 40 mg/ml)

Ex vivo fucosylation improves human cord blood engraftment in NOD-SCID IL-2Rγ null mice

Delayed engraftment remains a major hurdle after cord blood (CB) transplantation. It may be due, at least in part, to low fucosylation of cell surface molecules important for homing to the bone marrow microenvironment. Because fucosylation of specific cell surface ligands is required before effective interaction with selectins expressed by the bone marrow microvasculature can occur, a simple 30-minute ex vivo incubation of CB hematopoietic progenitor cells with fucosyltransferase-VI and its substrate (GDP-fucose) was performed to increase levels of fucosylation. The physiologic impact of CB hematopoietic progenitor cell hypofucosylation was investigated in vivo in NOD-SCID interleukin (IL)-2Rγ null (NSG) mice. By isolating fucosylated and nonfucosylated CD34 + cells from CB, we showed that only fucosylated CD34 + cells are responsible for engraftment in NSG mice. In addition, because the proportion of CD34 + cells that are fucosylated in CB is significantly less than in bone marrow and peripheral blood, we hypothesize that these combined observations might explain, at least in part, the delayed engraftment observed after CB transplantation. Because engraftment appears to be correlated with the fucosylation of CD34 + cells, we hypothesized that increasing the proportion of CD34 + cells that are fucosylated would improve CB engraftment. Ex vivo treatment with fucosyltransferase-VI significantly increases the levels of CD34 + fucosylation and, as hypothesized, this was associated with improved engraftment. Ex vivo fucosylation did not alter the biodistribution of engrafting cells or pattern of long-term, multilineage, multi-tissue engraftment. We propose that ex vivo fucosylation will similarly improve the rate and magnitude of engraftment for CB transplant recipients in a clinical setting

The erosion behavior of 304 stainless steel at elevated temperatures

The objective of this paper is to characterize the solid particle erosion behavior of an annealed 304 stainless steel (SS) over the temperature range of 300 to 763 K. Silicon carbide was used as the erodent. Impact velocity and angle were kept constant at 115 m/s and 90 deg (normal), respectively. The results indicated that the erosion rate of 304 SS as a function of test temperature went through a minimum at around 548 K. None of the empirical models or parameters proposed in the literature for correlating room-temperature erosion resistance with a variety of mechanical or thermophysical properties of the eroding or erodent material explained the observed erosion rate vs temperature behavior. However, the results were qualitatively explained on the basis of a localization model for erosion. An analysis of the erosion data also indicated that oxidation of the eroding material and related effects on erosion were unimportant even at the highest test temperature of 763 K

Various Trade-Off Scenarios in Thermo-Hydrodynamic Performance of Metal Foams Due to Variations in Their Thickness and Structural Conditions

The long standing issue of increased heat transfer, always accompanied by increased pressure drop using metal foams, is addressed in the present work. Heat transfer and pressure drop, both of various magnitudes, can be observed in respect to various flow and heat transfer influencing aspects of considered metal foams. In this regard, for the first time, orderly varying pore density (characterized by visible pores per inch, i.e., PPI) and porosity (characterized by ratio of void volume to total volume) along with varied thickness are considered to comprehensively analyze variation in the trade-off scenario between flow resistance minimization and heat transfer augmentation behavior of metal foams with the help of numerical simulations and TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) which is a multi-criteria decision-making tool to address the considered multi-objective problem. A numerical domain of vertical channel is modelled with zone of metal foam porous media at the channel center by invoking LTNE and Darcy–Forchheimer models. Metal foams of four thickness ratios are considered (1, 0.75, 0.5 and 0.25), along with varied pore density (5, 10, 15, 20 and 25 PPI), each at various porosity conditions of 0.8, 0.85, 0.9 and 0.95 porosity. Numerically obtained pressure and temperature field data are critically analyzed for various trade-off scenarios exhibited under the abovementioned variable conditions. A type of metal foam based on its morphological (pore density and porosity) and configurational (thickness) aspects, which can participate in a desired trade-off scenario between flow resistance and heat transfer, is illustrated

Various Trade-Off Scenarios in Thermo-Hydrodynamic Performance of Metal Foams Due to Variations in Their Thickness and Structural Conditions

The long standing issue of increased heat transfer, always accompanied by increased pressure drop using metal foams, is addressed in the present work. Heat transfer and pressure drop, both of various magnitudes, can be observed in respect to various flow and heat transfer influencing aspects of considered metal foams. In this regard, for the first time, orderly varying pore density (characterized by visible pores per inch, i.e., PPI) and porosity (characterized by ratio of void volume to total volume) along with varied thickness are considered to comprehensively analyze variation in the trade-off scenario between flow resistance minimization and heat transfer augmentation behavior of metal foams with the help of numerical simulations and TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) which is a multi-criteria decision-making tool to address the considered multi-objective problem. A numerical domain of vertical channel is modelled with zone of metal foam porous media at the channel center by invoking LTNE and Darcy–Forchheimer models. Metal foams of four thickness ratios are considered (1, 0.75, 0.5 and 0.25), along with varied pore density (5, 10, 15, 20 and 25 PPI), each at various porosity conditions of 0.8, 0.85, 0.9 and 0.95 porosity. Numerically obtained pressure and temperature field data are critically analyzed for various trade-off scenarios exhibited under the abovementioned variable conditions. A type of metal foam based on its morphological (pore density and porosity) and configurational (thickness) aspects, which can participate in a desired trade-off scenario between flow resistance and heat transfer, is illustrated

Room temperature erosion behaviour of 304, 316 and 410 stainless steels

The main purpose of this investigation is to compare the room temperature erosion behaviour of three stainless steels, namely 304, 316 and 410 SS. Towards this purpose, the erosion rates of all three stainless steels have been determined at three impact angles (30°, 60° and 90°) and at two impact velocities (98 and 129 m s<SUP>−1</SUP>) for each angle. The results indicate that while the erosion rates of 304 and 316 SS are comparable, that of 410 SS is lower by 15%-20%. The improved erosion resistance of 410 SS, in spite of its lower ductility and strain-hardening capacity as compared with 304 and 316 SS, appears to be related to the fact that the depth to which plastic deformation extends beneath the eroded surface (L) is significantly lower in 410 SS and also to the presence of a "soft zone" beneath the eroded surface

Correlations and Numerical Modeling of Stacked Woven Wire-Mesh Porous Media for Heat Exchange Applications

Metal foams have gained attention due to their heat transfer augmenting capabilities. In the literature, correlations describing relations among their morphological characteristics have successfully been established and well discussed. However, collective expressions that categorize stacked wire mesh based on their morphology and thermo-hydraulic expressions required for numerical modeling are less explored in the literature. In the present study, cross relations among the morphological characteristics of stacked wire-mesh were arrived at based on mesh-size, wire diameter and stacking type, which are essential for describing the medium and determining key input parameters required for numerical modeling. Furthermore, correlation for specific surface area, a vital parameter that plays a major role in interstitial heat transfer, is provided. With the arrived correlations, properties of stacked wire-mesh samples of orderly varied mesh-size and porosity are obtained for various stacking scenarios, and corresponding thermo-hydraulic parameters appearing in the governing equations are evaluated. A vertical channel housing the categorized wire-mesh porous media is numerically modeled to analyze thermal and flow characteristics of such a medium. The proposed correlations can be used in confidence to evaluate thermo-hydraulic parameters appearing in governing equations in order to numerically model various samples of stacked wire-mesh types of porous media in a variety of heat transfer applications