445 research outputs found
Non-Linear Realisation of the Pure N=4, D=5 Supergravity
We perform the non-linear realisation or the coset formulation of the pure
N=4, D=5 supergravity. We derive the Lie superalgebra which parameterizes a
coset map whose induced Cartan-Maurer form produces the bosonic field equations
of the pure N=4, D=5 supergravity by canonically satisfying the Cartan-Maurer
equation. We also obtain the first-order field equations of the theory as a
twisted self-duality condition for the Cartan-Maurer form within the
geometrical framework of the coset construction.Comment: 12 page
CFD modelling of a hollow fibre system for CO2 capture by aqueous amine solutions of MEA, DEA and MDEA
YesA mass transfer model was developed for CO2 capture from a binary gas mixture of N2/CO2 in hollow fibre membrane contactors under laminar flow conditions. The axial and radial diffusions through membrane and convection in tube and shell sides with chemical reaction were investigated. COMSOL software was used to numerically solve a system of non-linear equations with boundary conditions by use of the finite element method. Three different amine solutions of monoethanolamine (MEA), diethanolamine (DEA) and n-methyldiethanolamine (MDEA) were chosen as absorbent in lumen to consider the mass transfer rate of CO2 and compare their removal efficiency. The modelling results were compared with experimental data available in the literature and a good agreement was observed. The CFD results revealed that MEA had the best performance for CO2 removal as compared to DEA and MDEA under various operating conditions due to the different CO2 loading factor of absorbents. Furthermore, efficiency of CO2 removal was highly dependent on the absorbent concentration and its flow rate, increasing of the gas flow rate caused a reduction in gas residence time in the shell and consequently declined CO2 mass transfer. The modelling results showed the influence of the absorbent concentration on the CO2 mass transfer has improved due to availability of absorbent reactants at the gas-liquid interface
Proportional resource allocation in dynamic n-player Blotto games
In this note, we introduce a general model of dynamic n-player multi-battle Blotto contests in which asymmetric resources and non-homogeneous battlefield prizes are possible. Each player’s probability of winning the prize in a battlefield is governed by a ratio-form contest success function and players’ resource allocation on that battlefield. We show that there exists a pure subgame perfect equilibrium in which players allocate their resources in proportion to the battlefield prizes for every history. We also give a sufficient condition that if there are two players and the contest success function is of Tullock type, then the subgame perfect equilibrium is unique
Dualisation of the D=9 Matter Coupled Supergravity
We perform the bosonic dualisation of the matter coupled N=1, D=9
supergravity. We derive the Lie superalgebra which parameterizes the coset map
whose Cartan form realizes the second-order bosonic field equations. Following
the non-linear coset construction we present the first-order formulation of the
bosonic field equations as a twisted self-duality condition.Comment: 16 page
Investigation of the Growth of Particles Produced in a Laval Nozzle
YesThis study focuses on numerical modeling of condensation of water vapor in a Laval nozzle, using the liquid drop nucleation theory. Influence of nozzle geometry, pressure, and temperature on the average drop size is reported. A computer program written in MATLAB was used used to calculate the nucleation and condensation of water vapor in the nozzle. The simulation results are validated with the available experimental data in the literature for steam condensation. The model reveals that the average drop size is reduced by increasing the divergent angle of the nozzle. The results also confirm that increasing the inlet pressure has a direct effect on the average drop size while temperature rise has an inverse effect on the drop size
Pharmacutical effects of ephedrine, atropine and mucosal phenilephrin on hemodynamic alterations of women during spinal anesthesia in cesarean section
Background and Objective: Hemodynamic alteration and hypotension due to spinal anesthesia
can reduce tissue perfusion and increase ischemic risk, myocardial infraction, renal failures
spinal damages and even deep veins thrombosis. This study was designed to compare
pharmaceutical effects of ephedrine, atropine and mucosal phenilephrin on hemodynamic
alteration of women during spinal anesthesia in cesarean section.
Materials and Methods: This randomized clinical and double blind study was done on 90
singleton pregnant women with ASA I and II class .the subjects gone elective cesarean section
and allocated into three groups. subjects were received 500 ml ringer lactate before spinal
anesthesia. Subjects in group I, II and III first received 0.1 mg/kg atropine (IV) 0.01mg/kg
ephedrine and 100µgr phenilephrin (mucosal) prior spinal anesthesia, respectively.
Hemodaynamic indexes including blood pressure, heart Rate, oxygen saturation and drug side
effects were determined every 5 minutes interval through the surgery. Data was analyzed by
using SPSS-11.5, Chi-Square and ANOVA tests.
Results: Hemodaynamic indexes were changed during study, but three medicine showed similar
effect on heart Rate, blood pressure and changes of oxygen saturation (P<0.05). There was a
significant differences among three groups for dosage of extra ephedrine to control of blood
pressure (P<0.05). This increase dosage of extra ephedrine was 56.7%,20% and in ephedrine,
phenilephrin and atropine groups,respectively. Nosia rate was 6.7%, 50% and 46.7% in
phenilephrin, atropine and ephedrine groups, respectively (P<0.05).
Conclusion: This study showed that to prevent of blood pressure drop following spinal anestasia
atropine, phenilephrin and ephedrine can be prescribed, but ephedrine is recommended for
lowering the rate of nosi
Dualisation of the D=7 Heterotic String
The dualisation and the first-order formulation of the D=7 abelian Yang-Mills
supergravity which is the low energy effective limit of the D=7 fully Higssed
heterotic string is discussed. The non-linear coset formulation of the scalars
is enlarged to include the entire bosonic sector by introducing dual fields and
by constructing the Lie superalgebra which generates the dualized coset
element.Comment: 20 page
Comparisons of competitive enzyme-linked immunosorbent assay and one step RT-PCR tests for the detection of Bluetongue virus in south west of Iran
Bluetongue is a noncontagious, arthropod-borne viral disease of both domestic and wild ruminants. Bluetongue virus (BTV) is the type of species of the genus Orbivirus within the family Reoviridae. BTV is endemic in some areas with cattle and wild ruminants serving as reservoirs for the virus. Clinical symptoms are often seen in sheep. There are several methods for the detection of Bluetongue virus, among them the molecular technique like RT-PCR is considered as the most sensitive and reliable one. The aim of this study was to comprise competitive enzyme-linked immunosorbent assay (C-ELISA) with one step RT-PCR test for the detection of BTV in sheep. A total of 770 blood samples were obtained from sheep (265 serum positive samples and 505 serum negative samples in C-ELISA). According to our data, out of the 265 serum positive samples in ELISA test, 234 were positive in RT-PCR assay whereas all serum negative samples were negative in RT-PCR experiment. According to the results, the PCR assay was more sensitive and reliable than ELISA technique for the diagnosis of Bluetongue virus.Key words: Bluetongue virus, C-ELISA, RT- PCR, Sheep, Iran
Do Independent Directors Curb Financial Fraud? The Evidence and Proposals for Further Reform
In this article, we argue that the U.S. corporate governance rules put too much faith in the independent board members and insufficient emphasis on the shareholders themselves to control and monitor the top management. Given the agency problem between the board of directors and the shareholders, outside directors can be captured by management, thereby leading to inadequate checks on management. The evidence presented in this paper shows that outside board members do not exercise sufficient controls on the management even when the management has gone awry. To solve this agency problem, we propose increasing the power of the principals: make shareholder resolutions binding on management, require a one share, one vote rule to increase the voting rights of shareholders, as well as give the shareholders the ability to directly nominate and/or actively vote against board members.https://deepblue.lib.umich.edu/bitstream/2027.42/139595/1/1352_Schipani_Nov17.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139595/4/1352_Schipani_Aug18.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139595/6/1352_SchipaniOct2018.pdfDescription of 1352_Schipani_Aug18.pdf : Aug 2018 Pre-publication draftDescription of 1352_SchipaniOct2018.pdf : October 2018 revisio
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