Resistance to tomato plants to Verticillium albo-atrum

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Class of Semihyperrings from Partitions of a Set

In this paper we show that a partition {P α : α ∈ Λ} of a non-empty set S, where Λ is an ordered set with the least element α 0 and P α 0 is a singleton set, induces a hyperaddition + such that (S,+) is a commutative hypermonoid. Also by using a collection of subsets of S, induced by the partition of the set S, we define hypermultiplication on S so that (S,+,·) is a semihyperring

Ultrasonic propagation in solids

This dissertation gives a critical survey of the present state of knowledge in the field of ultrasonic propagation in solids. Acoustic waves of high frequency suffer absorption during propagation and the analysis of this absorption has both theoretical and technical interest. The observed loss mechanisms in solids: thermal conductivity, thermoelastic relaxation, scattering, plastic flow, structural relaxation, anharmonic coupling and magnetic effects. Theoretical explanations of these various types of losses in single and polycrystalline solids and also in high polymers, such as in rubbers and plastics are given. For reliable measurements, suitable transducers and precision experimental techniques are essential. Ultrasonic generators such as magnetostrictive, piezo electric, and the recently developed multicrystalline ceramic transducers are described. The experimental procedures for the measurement of sound velocity and attenuation during propagation are broadly grouped into three classes, (a) Resonant methods, (b) Optical methods, and (c) Pulse techniques. Optical diffraction methods are extensively used for velocity measurement and for the determination of elastic and elasto-optic constants of solids, whereas the resonant and pulse methods are used for both velocity and absorption measurement. At megacycle frequencies, at present, the pulse technique is the only method for precision absorption measurement. The recent measurement of attenuation at low temperatures and the relation with 'dislocation' theory are discussed. Attenuation measurements lead to another practical application in the use of certain solids, as delay lines in radar systems and in devices for storing informations. A chapter on solid delay lines has been included. The equivalence of the theory of heat and high frequency sound transmission and the earlier theory of heat transmission by Debye, have been discussed

Seven Level Modified Cascaded Inverter for Induction Motor Drive Applications

In this paper, an H-bridge inverter topology with reduced switch count technique is introduced. This technique reduces the number of controlled switches used in conventional multilevel inverter. To establish a single phase system, the proposed multilevel inverter requires one H-bridge and a multi conversion cell. A multi conversion cell consists of three equal voltage sources with three controlled switches and three diodes. In conventional method, twelve controlled switches are used to obtain seven levels. Due to involvement of twelve switches the harmonics, switching losses, cost and total harmonic distortion are increased. This proposed topology also increases the level to seven with only seven controlled switches. It dramatically reduces the complexity of control circuit, cost, lower order harmonics and thus effectively reduces total harmonic distortion. Keywords: Cascaded Multilevel Inverter, H-bridge Inverter, Total Harmonic Distortion, Sinusoidal Pulse Width Modulation, Insulated Gate Bipolar Transisto

In vitro antioxidant activity of Vetiveria zizanioides root extract

Free radicals induce numerous diseases by lipid peroxidation and DNA damage. It has been reported that some of the extracts from plants possess antioxidant properties capable of scavenging free radicals in vivo. Vetiveria zizanioides belonging to the family Gramineae, is a densely tufted grass which is widely used as a traditional plant for aromatherapy, to relieve stress, anxiety, nervous tension and insomnia. In this regard, the roots of V. zizanioides was extracted with ethanol and used for the evaluation of various in vitro antioxidant activities such as reducing power ability, superoxide anion radical scavenging activity, deoxyribose degradation assay, total antioxidant capacity, total phenolics and total flavonoid composition. The various antioxidant activities were compared with suitable antioxidants such as butyl hydroxy toluene, ascorbic acid, quercetin, alpha tocopherol, pyrocatechol and curcumin respectively. The generation of free radicals O2·, H2O2, OH and N O· were effectively scavenged by the ethanolic extract of V. zizanioides. In all these methods, the extract showed strong antioxidant activity in a dose dependent manner. The results obtained in the present study clearly indicates that V. zizanioides scavenges free radicals, ameliorating damage imposed by oxidative stress in different disease conditions and serve as a potential source of natural antioxidant. The study provides a proof for the ethnomedical claims and reported biological activities. The plant has, therefore, very good therapeutic and antioxidant potential

In vitro antioxidant activity of Vetiveria zizanioides root extract

Free radicals induce numerous diseases by lipid peroxidation and DNA damage. It has been reported that some of the extracts from plants possess antioxidant properties capable of scavenging free radicals in vivo. Vetiveria zizanioides belonging to the family Gramineae, is a densely tufted grass which is widely used as a traditional plant for aromatherapy, to relieve stress, anxiety, nervous tension and insomnia. In this regard, the roots of V. zizanioides was extracted with ethanol and used for the evaluation of various in vitro antioxidant activities such as reducing power ability, superoxide anion radical scavenging activity, deoxyribose degradation assay, total antioxidant capacity, total phenolics and total flavonoid composition. The various antioxidant activities were compared with suitable antioxidants such as butyl hydroxy toluene, ascorbic acid, quercetin, alpha tocopherol, pyrocatechol and curcumin respectively. The generation of free radicals O2-, H2O2, OH and NO were effectively scavenged by the ethanolic extract of V.zizanioides. In all these methods, the extract showed strong antioxidant activity in a dose dependent manner. The results obtained in the present study clearly indicates that V. zizanioides scavenges free radicals, ameliorating damage imposed by oxidative stress in different disease conditions and serve as a potential source of natural antioxidant. The study provides a proof for the ethnomedical claims and reported biological activities. The plant has, therefore, very good therapeutic and antioxidant potential

Investigation of Antidiabetic, Antihyperlipidemic, and In Vivo Antioxidant Properties of Sphaeranthus indicus Linn. in Type 1 Diabetic Rats: An Identification of Possible Biomarkers

The present investigation was aimed to study the antidiabetic, antihyperlipidemic, and in vivo antioxidant properties of the root of Sphaeranthus indicus Linn. in streptozotocin- (STZ-) induced type 1 diabetic rats. Administration of ethanolic extract of Sphaeranthus indicus root (EESIR) 100 and 200 mg/kg to the STZ-induced diabetic rats showed significant (P < .01) reduction in blood glucose and increase in body weight compared to diabetic control rats. Both the doses of EESIR-treated diabetic rats showed significant (P < .01) alteration in elevated lipid profile levels than diabetic control rats. The EESIR treatment in diabetic rats produced significant increase in superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and decrease in thiobarbituric acid reactive substances (TBARS) levels than diabetic control rats. Administration of EESIR 200 mg/kg produced significant (P < .01) higher antioxidant activity than EESIR 100 mg/kg. The high performance liquid chromatography (HPLC) analysis of EESIR revealed the presence of biomarkers gallic acid and quercetin. In conclusion, EESIR possess antidiabetic, antihyperlipidemic, and in vivo antioxidant activity in type 1 diabetic rats. Its antioxidant and lipid lowering effect will help to prevent diabetic complications, and these actions are possibly due to presence of above biomarkers

Discovery of potential cholesterol esterase inhibitors using in silico docking studies

New drug discovery is considered broadly in terms of two kinds of investigational activities such as exploration and exploitation. This study deals with the evaluation of the cholesterol esterase inhibitory activity of flavonoids apigenin, biochanin, curcumin, diosmetin, epipervilline, glycitein, okanin, rhamnazin and tangeritin using in silico docking studies. In silico docking studies were carried out using AutoDock 4.2, based on the Lamarckian genetic algorithm principle. The results showed that all the selected flavonoids showed binding energy ranging between -7.08 kcal/mol to -5.64 kcal/mol when compared with that of the standard compound gallic acid (-4.11 kcal/mol). Intermolecular energy (-9.13 kcal/mol to -7.09 kcal/mol) and inhibition constant (6.48 µM to 73.18 µM) of the ligands also coincide with the binding energy. All the selected flavonoids contributed cholesterol esterase inhibitory activity, these molecular docking analyses could lead to the further develop-ment of potent cholesterol esterase inhibitors for the treatment of obesity