934 research outputs found
Boundary conditions and Berry phase in magnetic nanostructures
The effect of micromagnetic boundary conditions on the Berry curvature and topological Hall effect in granular nanostructures is investi- gated by model calculations. Both free surfaces and grain boundaries between interacting particles or grains affect the spin structure. The Dzyaloshinskii-Moriya interactions yield corrections to the Erdmann-Weierstrass boundary conditions, but the Berry curvature remains an exclusive functional of the local spin structure, which greatly simplifies the treatment of nanostructures. An explicit example is a model nanostructure with cylindrical symmetry whose spin structure is described by Bessel function and which yields a mean-field-type Hall-effect contribution that can be related to magnetic-force-microscopy images
Establishing Contingency Analysis with FACTS Devices Using Power World Simulator
Contingency analysis is the protection of power system operation under the loss of one or more of the major power system components. It is widely used to predict the effect of outages of transmission lines and generators. To calculate the number of violation, contingency analysis is the most preferable choice. Power systems use contingency analysis to foretell the result of any component failure. Contingency analysis is an application that uses a simulated model of power system to judge the result and calculate any overload. The proposed method approaches the flexible AC transmission system (FACTS) device to reduce the power flow in heavily loaded line and also increase the system performance. In this work, FACTS devices were implemented in IEEE 6-bus and IEEE 14-bus system and it is simulated by using Power World Simulator Software.Citation:Ă‚Â MONISHA, B., and Balamurugan, K. (2018). Establishing Contingency Analysis with FACTS Devices Using Power World Simulator. Trends in Renewable Energy, 4, 114-131. DOI: 10.17737/tre.2018.4.3.005
Cultural Diversity among the Employees and its Effect in Organizational Climate
Cultural diversity is a group of diverse individuals from different cultures or societies. The study is conducted to explore how manage workforce diversity and its consequences to the company’s existence as well as examine how companies’ deal with challenges that comes with employees from diverse cultural backgrounds. The study describe diversity challenges that can affect the working climate and conflict between the employees through the diversity .The result shows that cultural diversity plays an effective role in some companies however inadequate mentoring and guidance could cause a company low productivity. For this reason there is must be regular improvement in ways to effectively manage a cultural diverse in workforce as the world keeps advancing
COMBINED EFFECT OF SELECTIVE BIOACTIVE COMPOUNDS FROM PLANT ORIGIN IN AN ANIMAL MODEL OF ANXIETY
Objective: Evidence is emerging that specific combinations of bioactive compounds may be far more effective in protecting against several diseases as compared to the effect of a single compound. The present study was aimed to investigate the interactive effect of Diosgenin and Silymarin, the bioactive compounds from plant origin in an animal model of anxiety.
Methods: Albino wistar rats of either sex were divided into five groups and treated for 5 d. Group I and II served as control and standard and test groups were treated with Diosgenin (100 mg/kg, p. o.), Silymarin (100 mg/kg, p. o.) and combination of Diosgenin (50 mg/kg, p. o.)+Silymarin (50 mg/kg, p. o.), respectively. Diazepam (1 mg/kg, i. p.) was used as a standard for the study. Anxiolytic effects were studied in the Elevated plus-maze, Hole-board test and Light/Dark model.
Results: The results suggested that Diosgenin when given alone at a dose of 100 mg/kg, does not shown significant anxiolytic effect when as compared with control. Whereas, the compound Silymarin (100 mg/kg) shown significant anti-anxiety effect (P<0.01), independently. The same two bioactive compounds, given in combination at a dose of 50 mg/kg, (each), exhibited significant anxiolytic-like effect, potentially.
Conclusion: It can be concluded that Diosgenin has got a synergistic effect on anti-anxiety action when given in combination with Silymarin
Studies on nutrient solubilization, biocontrol and plant growth promoting traits of Burkholderia cepacia from tea soil
A study was undertaken to isolate a novel indigenous bacterial strain namely Burkholderia cepacia from tea soils to solubilize potassium (K) and phosphorus (P) sources respectively. The isolated strain was screened based on its solubilization potential in both broth and agarized medium amended with various K and P sources. Plant growth promoting traits and biocontrol activity of the purified strain against tea pathogens such as Pestalotiopsis theae, Glomerella cingulata, Poria hypolateritia, Phomopsis theae and Hypoxylon serpens were studied. Results revealed a significant solubilizing zone in agar medium blended with muriate of potash (MOP) (2.0 cm), sulphate of potash (SOP) (1.2 cm), rock phosphate (1.6 cm) and single super phosphate (0.8 cm). The release of available K was quantified in liquid medium supplemented with MOP and was found to be higher (41.5 mg L-1) than SOP. Among different P sources, rock phosphate (35.2 mg L-1) showed higher solubilization than single super phosphate (30.2 mg L-1) by the test organism on 5th day of incubation. B. cepacia was found to produce a large amount of bioactive compounds like siderophore (12.3 ÎĽg mL-1), IAA (263.3 ÎĽg mL-1) and GA3 (14.9 ÎĽg mL-1) including exo-polysaccharides (46.8 ppm). The test organism also showed a remarkable biocontrol activity against P. theae (52.5%), G. cingulata (42.5%), H. serpens (47.5%), Phomopsis theae (32.7%) and P. hypolateritia (30.9%). The secondary metabolites production by an efficient strain B. cepacia revealed that the strain could produce a wide range of volatile compounds
Occurrences of pathogenic Vibrio parahaemolyticus from Vellar estuary and shrimp ponds
Vibrio parahaemolyticus is the predominant seafood pathogen associated with human gastroenteritis. Samples were collected from Vellar estuary, shrimp ponds and shrimp for characterization of V. parahaemolyticus. A total of 26 blue green centre (BG) Vibrio strains were isolated and characterized through biochemical tests, toxR gene and 16S rRNA gene sequencing. Based on pathogenic characteristics, six strains were confirmed as pathogenic V. parahaemolyticus. This report implies that preventative measure must be taken before consumption of fish and shrimp.Keywords: Estuary, shrimp pond, Vibrio parahaemolyticus, protease, haemolysis, toxR geneAfrican Journal of Biotechnology Vol. 12(14), pp. 1624-162
Self-vacancies in Gallium Arsenide: an ab initio calculation
We report here a reexamination of the static properties of vacancies in GaAs
by means of first-principles density-functional calculations using localized
basis sets. Our calculated formation energies yields results that are in good
agreement with recent experimental and {\it ab-initio} calculation and provide
a complete description of the relaxation geometry and energetic for various
charge state of vacancies from both sublattices. Gallium vacancies are stable
in the 0, -, -2, -3 charge state, but V_Ga^-3 remains the dominant charge state
for intrinsic and n-type GaAs, confirming results from positron annihilation.
Interestingly, Arsenic vacancies show two successive negative-U transitions
making only +1, -1 and -3 charge states stable, while the intermediate defects
are metastable. The second transition (-/-3) brings a resonant bond relaxation
for V_As^-3 similar to the one identified for silicon and GaAs divacancies.Comment: 14 page
Postbuckling Behaviour of Anisotropic Laminated Composite Plates due to Shear Loading
This study investigates postbuckling behaviour of laminated composite plates using a nine-noded shear flexible quadrilateral plate element. The formulation includes nonlinear strain-displacement relation based on von Karman's assumption. The nonlinear governing equations are solved through iteration. A detailed parametric study is carried out to bring out the influence of ply-angle, aspect ratio and material properties on the postbuckling strength of laminates due to in-plane shear loads
Obstetric Renal Failure: A Prospective study
INTRODUCTION :
The unique vulnerability of the kidneys in pregnancy was first noted in 1843 when John Lever recognized that proteinuria occurring in association with maternal convulsions was an entity separate from chronic kidney disease. Lever’s observation came 16 years after Richard Bright’s recognition of proteinuria as a marker for kidney disease. The distinction between primary kidney disease and preeclampsia remains one of the most common issues addressed by nephrologists seeing pregnant women.
Pregnancy in a woman with kidney disease or the development of primary kidney disease in a pregnant woman has long been recognized as dangerous. In 1936, Dieckman recommended termination of pregnancy if nephrosis occurred before 30 weeks gestation. At that time, not only was there no effective treatment for kidney failure, but antibiotics, steroids, and effective antihypertensive treatment were not available. Women with known kidney disease were discouraged from becoming pregnant, and most of our knowledge about pregnancy in kidney disease has been acquired only because women wanted children ignored the advice of their physicians.
In 1970 Lindheimer and Katz observed that successful pregnancy was the rule in women with kidney disease whose kidney function was well preserved. Some investigators associated poor outcomes with specific glomerular lesions, and only later did it become clear that preconception
serum creatinine was more important than the specific kidney disease (except in case of lupus nephritis). Until the 1980, most series of pregnancy in women with kidney disease included only a few women with serum creatinine greater than 1.4 mg/dl. Over the following 10 years, more than 7
reports were published detailing 226 pregnancies in 196 women with moderate to severe preexisting kidney disease. Collective experience indicated that these women risked more rapid progression to kidney failure if they became pregnant. At the same time, advances in the care of premature newborns resulted in the survival of more than 90% of infants
from pregnancies in this group of women.
MATERIALS AND METHODS :
All patients who were referred to Department of Nephrology with renal failure complicating pregnancy between Jan 2006 and Jan 2008 were included in this study. Total patients were 52 in number. All of these patients were referred from different parts of Tamilnadu. Most of these patients were referred from Department of Obstetrics attached to our college and from various District headquarters hospital. Their age ranged between 20 and 35 years, the mean being 25.5 years.
CONCLUSION :
Pregnancy-related ARF has virtually disappeared from the
economically advanced countries. This progress is chiefly attributed to legalized abortion, consequently, to a decline in septic abortion, and improvement in antenatal care. The incidence of severe ARF in pregnancy is high in the Indian and septic abortion remains the major cause of ARF.
Despite legalization of abortion, good number pregnant women seek abortion from untrained and unlicensed abortionist under unhygienic conditions, probably due to social stigma attached to abortion. In contrast to the low rates of cortical necrosis (1.5%). In early pregnancy in western countries its incidence remains high (25%) in India. The frequency distribution of ARF in pregnancy is still bimodal in Indian subcontinent, where as early peak of ARF in pregnancy has disappeared in the developed countries. Thus, ARF in pregnancy is larger in largely preventable because it is usually the result of obstetric complication and not
intrinsic renal disease. With this in mind, pregnancy related acute renal failure could be viewed as a public health problem rather than a nephrological problem
Vulval carcinoma at the site of recent Bartholin gland excision: a rare case report
Around 2-7% of all vulvar cancers are represented by primary carcinomas of Bartholin gland. Here we are presenting such a rare case of carcinoma of Bartholin gland. 45/F P2L2 presented in our OPD with non-healing lesion in vulva for 2 months. She had history of Bartholin’s cyst excision (elsewhere), 2 months back (the exact time since when she is having the non-healing lesion in vulva). Diagnostic biopsy revealed it to be vulval squamous cell carcinoma. She was given two cycles of Neo adjuvant chemotherapy (Inj. Paclitaxel and Carboplatin). In view of better response to the treatment patient was planned for surgery. Patient underwent wide local excision with bilateral inguinofemoral lymphadenectomy. Although the majority of vulvar lesions are benign, especially in women younger than 50 years of age, any solid mass should be carefully evaluated for malignancy. Preferably biopsy of Bartholin gland should be considered if the patient is more than 40 years of age and should be mandatory in a menopausal woman
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