99 research outputs found

    Bounds on Energy and Laplacian Energy of Graphs

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    Let G be simple graph with n vertices and m edges. The energy E(G) of G, denotedby E(G), is dened to be the sum of the absolute values of the eigenvalues of G. Inthis paper, we present two new upper bounds for energy of a graph, one in terms ofm,n and another in terms of largest absolute eigenvalue and the smallest absoluteeigenvalue. The paper also contains upper bounds for Laplacian energy of graph

    Efficacy and safety of two different doses of intrathecal calcitonin, a randomized controlled study

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    Background: Adjuvants play an important role in enhancing the quality of anesthesia and also in reducing the requirement of primary anesthetic and its related adverse events. Calcitonin is one such adjuvant. But there is still uncertainty regarding the appropriate dose of calcitonin to achieve maximum analgesic efficacy and safety. The current study is conducted to add to the existing evidence on the subject and was aimed to compare the efficacy and safety of two different doses of calcitonin as an adjuvant in patients undergoing spinal anesthesia.Methods: A prospective randomized controlled double-blind trial was conducted in the Department of Anesthesiology and Intensive Care, Sir Sunderlal Hospital, Banaras Hindu University from May 2006 to May 2007. A total of 80 participants aged between 18 to 60 years, with ASA I and II physical status, undergoing infra-umbilical surgeries were randomly allocated to one of the 4 intervention groups. All the 4 intervention groups received 0.5% bupivacaine (H) 3ml as a primary anesthetic agent. Group I and III received 50 IU and 100 IU salmon calcitonin as an adjuvant. Group II received placebo and group IV (control) received no adjuvant. Pinprick test, Bromage scale and 10-point Visual analog scale (VAS) were used to measure the efficacy.Results: All the study groups were comparable with respect to all baseline variables. The time interval to the first dose of analgesia was longest in 100 I.U. calcitonin group, followed by 50 I.U. calcitonin group, placebo control group. The mean duration of analgesia (in minutes) among group I (100I.U. calcitonin) was 230.00±92.39, 159.25±21.59 among group II (Placebo), 161.50±31.20 among group III (50 I.U. calcitonin) and 142.75±20.22 among group IV. Considering group IV (control group) as base line. The differences of duration of analgesia (in minutes) in group I, group II and group III with baseline value (group IV) were statistically significant (P value <0.05). Even though the proportion of subjects developing adverse events was slightly higher in 100 I.U calcitonin groups compared to other groups, they were minor adverse events and were managed appropriately. There were no significant differences across the study groups in terms of hemodynamic stability.Conclusions: Salmon calcitonin as adjuvant increases the duration of postoperative analgesia. Even though the there slightly higher incidence of adverse events with 100 I.U calcitonin they are minor and the risk-benefit ratio favors calcitonin use. To make a categorical recommendation on the appropriate dose, there is further need for large-scale studies and pooled analysis

    Assessment of Radon in groundwater and associated human risk from Sankarabarani River Sub Basin, Southern India

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    Radon (222Rn) and associated human risk assessment in groundwater from quaternary shallow aquifers of Sankarabarani River sub basin, Southern India has been attempted by considering 41 groundwater samples and analysed for 222Rn using scintillation Radon monitoring system. The Radon ranges between 0.140±0.01 Bq l-1 to 7.869±0.33 Bq l-1 with an average of 1.797±0.12Bq l-1 and found to be within the maximum contamination level of Environmental Protection Agency (11.1 Bq l-1). The doses of ingestion and inhalation calculated for radon varies between 0.709 µSv y-1 to 39.933µSv y-1 with an average of 9.121µSv y-1which is within the prescribed dose limit of 100µSv y-1 by World Health Organisation. Uranium speciation attempted suggests saturated Haiweeite and Soddyite as sources for uranium/radon into the aquifer systems. The Eh-pH diagram suggests uraninite solubility within the pH ranges 6 to 8 within the groundwater environment

    Vector rogue waves and dark bright boomeronic solitons in autonomous and non autonomous settings

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    In this work, we consider the dynamics of vector rogue waves and ark bright solitons in two component nonlinear Schrodinger equations with various physically motivated time dependent non linearity coefficients, as well as spatio temporally dependent potentials. A similarity transformation is utilized to convert the system into the integrable Manakov system and subsequently the vector rogue and dark bright boomeron like soliton solutions of the latter are converted back into ones of the original non autonomous model. Using direct numerical simulations we find that, in most cases, the rogue waves formation is rapidly followed by a modulational instability that leads to the emergence of an expanding soliton train. Scenarios different than this generic phenomenology are also reported

    Investigation of Submarine Groundwater Discharge using Thermal Satellite and Radon mapping along the East Coast of the Tamil Nadu and Pondicherry Region, India

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    Submarine groundwater discharge (SGD) demarcated as a significant component of hydrological cycle found to discharge greater volumes of terrestrial fresh and recirculated seawater to the ocean associated with chemical constituents (nutrients, metals, and organic compounds) aided by downward hydraulic gradient and sediment-water exchange. Delineating SGD is of primal significance due to the transport of nutrients and contaminants due to domestic, industrial, and agricultural practices that influence the coastal water quality, ecosystems, and geochemical cycles. An attempt has been made to demarcate the SGD using thermal infrared images and radon-222 (222Rn) isotope. Thermal infrared images processed from LANDSAT-8 data suggest prominent freshwater fluxes with higher temperature anomalies noted in Cuddalore and Nagapattinam districts, and lower temperature noted along northern and southern parts of the study area suggest saline/recirculated discharge. Groundwater samples were collected along the coastal regions to analyze Radon and Physico-chemical constituents. Radon in groundwater ranges between 127.39 Bq m-3 and 2643.41 Bq m-3 with an average of 767.80 Bq m-3. Calculated SGD fluxes range between -1.0 to 26.5 with an average of 10.32 m day-1. Comparison of the thermal infrared image with physio-chemical parameters and Radon suggest fresh, terrestrial SGD fluxes confined to the central parts of the study area and lower fluxes observed along with the northern and southern parts of the study area advocate impact due to seawater intrusion and recirculated seawater influence

    Estimating groundwater inputs from Sankarabarani River Basin, South India to the Bay of Bengal evaluated by Radium (226Ra) and nutrient fluxes

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    Sankarabarani river basin gains significance due to presence of major industrial, agricultural, urban development and tourist related activities has influenced the water quality in the estuarine environment.&nbsp; Investigations about river water quality has been attempted but not more studies focus about the evaluation of groundwater discharge a significant process that connects groundwater and the coastal seawater have been attempted.&nbsp; For the present study, radium (226Ra) a naturally occurring isotope was measured at three locations and used as effective tracers for estimating the groundwater discharge along with nutrient inputs to the Bay. Groundwater samples representing north east monsoon (December, 2017) has been collected during tidal variation in three locations (Location A- away from the coast towards inland, Location B-intermediate between Location A and the coast and Location C-at the estuary). 226Ra mass balance calculated groundwater fluxes irrespective of tidal variations were 2.27×108 m3/d, 2.19×108 m3/d and 5.22×107m3/d for A, B and C locations respectively. The nutrients like Dissolved inorganic nitrogen (DIN), Dissolved inorganic Phosphate (DIP) and Dissolved Silica (DSi) were found to be influencing the coastal groundwater by contributing fluxes to the sea of about 679.33 T mol/day. The study suggests increasing radium and nutrient fluxes to the Bay altering the coastal ecosystems would result in surplus algal blooms creating hypoxia

    Exact soliton solutions, shape changing collisions and partially coherent solitons in coupled nonlinear Schroedinger equations

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    We present the exact bright one-soliton and two-soliton solutions of the integrable three coupled nonlinear Schroedinger equations (3-CNLS) by using the Hirota method, and then obtain them for the general NN-coupled nonlinear Schroedinger equations (N-CNLS). It is pointed out that the underlying solitons undergo inelastic (shape changing) collisions due to intensity redistribution among the modes. We also analyse the various possibilities and conditions for such collisions to occur. Further, we report the significant fact that the various partial coherent solitons (PCS) discussed in the literature are special cases of the higher order bright soliton solutions of the N-CNLS equations.Comment: 4 pages, RevTex, 1 EPS figure To appear in Physical Review Letter

    Pseudo cardiac tamponade in the setting of excess pericardial fat

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    Cardiac tamponade is the phenomenon of hemodynamic compromise caused by a pericardial effusion. Following a myocardial infarction, the most common causes of pericardial fluid include early pericarditis, Dressler's syndrome, and hemopericardium secondary to a free wall rupture. On transthoracic echocardiography, pericardial fluid appears as an echo-free space in between the visceral and parietal layers of the pericardium. Pericardial fat has a similar appearance on echocardiography and it may be difficult to discern the two entities. We present a case of a post-MI patient demonstrating pseudo tamponade physiology in the setting of excessive pericardial fat
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