1,574 research outputs found
Micropalaeontological studies of recent sediments from the Cilicia Basin (N.E. Mediterranean)
Imperial Users onl
Berry's phase in noncommutative spaces
We introduce the perturbative aspects of noncommutative quantum mechanics.
Then we study the Berry's phase in the framework of noncommutative quantum
mechanics. The results show deviations from the usual quantum mechanics which
depend on the parameter of space/space noncommtativity.Comment: 7 pages, no figur
Bound of Noncommutativity Parameter Based on Black Hole Entropy
We study the bound of the noncommutativity parameter in the noncommutative
Schwarzschild black hole which is a solution of the noncommutative ISO(3,1)
Poincare gauge group. The statistical entropy satisfying the area law in the
brick wall method yields a cutoff relation which depends on the
noncommutativity parameter. Requiring both the cutoff parameter and the
noncommutativity parameter to be real, the noncommutativity parameter can be
shown to be bounded as .Comment: LaTeX 7 pages, references added, minor correction
Nucleate pool boiling heat transfer of binary nano mixtures under atmospheric pressure around a smooth horizontal cylinder
Influence of Al2O3 nanoparticles on nucleate pool boiling heat transfer of diluted binary water-glycerol mixtures has been experimentally measured up to heat flux 91 kW/m2 at diluted volume fractions of 1% to 5% of glycerol into pure water at volumetric concentrations 0.5%, 1% and 1.5% of Al2O3 nanoparticles. Obtained results indicate that presence of nanoparticles into the mixtures result in increasing the pool boiling heat transfer coefficient values and also result in decreasing the wall superheat temperature of surface. Increased values of heat transfer are increased with increasing the volume fractions of Al2O3 too. Generally, it is concurred that Al2O3 nanoparticles typically enhance the pool boiling heat transfer coefficient of binary water-glycerol mixture in comparison with absence of nanoparticles circumstances, up to 25% at 1.5% Al2O3. Additionally, new simple semi - mathematical model has been proposed for a rough estimating of enhanced values with uncertainty about 8%
The Noncommutative Anandan's Quantum Phase
In this work we study the noncommutative nonrelativistic quantum dynamics of
a neutral particle, that possesses permanent magnetic and electric dipole
momenta, in the presence of an electric and magnetic fields. We use the
Foldy-Wouthuysen transformation of the Dirac spinor with a non-minimal coupling
to obtain the nonrelativistic limit. In this limit, we will study the
noncommutative quantum dynamics and obtain the noncommutative Anandan's
geometric phase. We analyze the situation where magnetic dipole moment of the
particle is zero and we obtain the noncommutative version of the
He-McKellar-Wilkens effect. We demonstrate that this phase in the
noncommutative case is a geometric dispersive phase. We also investigate this
geometric phase considering the noncommutativity in the phase space and the
Anandan's phase is obtained.Comment: 15 pages, revtex4, version to appear in Physical Review
Comparing the Effects of Active and Passive Intradialytic Pedaling Exercises on Dialysis Efficacy, Electrolytes, Hemoglobin, Hematocrit, Blood Pressure and Health-Related Quality of Life
Background: The effect of exercise during hemodialysis has been a controversial issue, however, there are just few studies about the effect of active exercise during hemodialysis.
Objectives: This study aimed to compare the effects of passive and active intradialytic pedaling exercises on dialysis efficacy, electrolytes, hemoglobin, hematocrit, blood pressure and health-related quality of life in hemodialysis patients.
Patients and Methods: This quasi-experimental study was conducted on 16 hemodialysis patients in Akhavan hemodialysis center in Kashan from April to November 2013. Active or passive intradialytic pedaling exercise was performed using a Mini-Bike for 30 minutes during the first two hours of the dialysis sessions. The quality of life (QOL) was assessed before and after the intervention. Blood pressure was examined at the beginning and then hourly during the dialysis sessions. Dialysis efficacy, levels of phosphorus, calcium, sodium, potassium and Blood urea nitrogen (BUN) were measured at the end of the intervention. Kolmogorov-Smirnov test, paired t test, Wilcoxon signed rank and Friedman tests and repeated measure analysis of variancewere used to analyze the data.
Results: No significant changes were observed in serum potassium, phosphorus and calcium levels at the end of the passive exercise program compared to the baseline. However, phosphorus levels were significantly decreased in the active exercise program (P < 0.05). Moreover, the mean diastolic blood pressure was significantly decreased after the passive exercise (P = 0.039). Passive exercise did not significantly change the dialysis efficacy, urea reduction rate, hemoglobin and calcium levels. The mean overall QOL was 63.78 ± 21.15 at the beginning of the study, which was increased to 77.07 ± 21.14 at the end of eight weeks of the intradialytic exercise (P = 0.007).
Conclusions: The passive intradialytic exercise had a positive effect on blood pressure. The active exercise could decrease the serum phosphorus and potassium levels. Moreover, both exercise programs could significantly improve the QOL. Both active and passive intradialytic exercises can have some beneficial effects
Comparison of antibiotics and bacteriocins antibacterial activity on Xanthomonas citri subsp.citri
Citrus canker is a citrus disease species created by the bacterium Xanthomonas citri subsp.citri. Many citrus, such as oranges, lime, and grapefruit are affected by the infectious bacteria and stems, leaves and fruits are experiencing loss. In this experiment antibacterial effects of five kinds of antibiotics including ampicillin, kanamycin, chloramphenicol, penicillin, streptomycin, Cronobacteriocin DGH2 and Enterobacteriocin DGH4 were evaluated on 107 strains of Xanthomonas citri subsp.citri. MIC and MBC data for antibiotics and bacteriocins against Xanthomonas strains were performed. According to this project, Xanthomonas strains were comparatively susceptible and resistant to Cronobacteriocin DGH2, Enterobacteriocin DGH4, ampicillin, kanamycin, chloramphenicol, penicillin and streptomycin. NIGEB-183 strain is the most sensitive to these antibiotics and bacteriocins. However, only the NIGEB-242R1 strain is resistant to chloramphenicol. Penicillin has minimum inhibitory effects on Xanthomonas strains. Based on this case study, chloramphenicol is the most antibacterial activity among antibacterial agents and this compound is a good candidate for inhibitory activity. Cronobacteriocin DGH2 has a moderate antibacterial activity against Xanthomonas strains
Effect of Estradiol and Soy Extract on the Onset of PTZ-Induced Seizure in Ovariectomized Rats: Implications for Nurses and Midwives
Background: In many epileptic women, the ovarian cycle influences the risk and severity of seizures. Previous studies have reported inconsistent findings regarding the neural excitatory effects of estrogen. Soybean is a rich source of plant estrogens. Therefore, soy intake can affect the risk and severity of seizures in women. Nurses and midwives need to be aware of the effects of diets containing estrogen in pregnant and post-menopausal women, as well as during the sexual cycle periods.
Objectives: Due to the limitations of human studies, this study aimed to investigate the effect of estradiol and soy extract on the onset of pentylenetetrazol (PTZ)-induced seizures in ovariectomized rats.
Materials and Methods: In this experimental study, sixty female Wistar rats were randomly divided into six groups of ten. All of the groups except for the negative control groups were ovariectomized. One group received estradiol (100 µg/kg), one group was treated with alcoholic extract of soy (20 mg/kg), and the other group received vehicle over 28 days. PTZ (90 mg/kg) was used to induce seizure in all groups. Behavioral changes were observed over 30 minutes. All data were analyzed using a two-way analysis of variance with Tukey’s post-hoc test.
Results: The mean ± SD of the clonic seizure threshold was 61.84 ± 8.53 in the group that received estradiol, while it was 71.70 ± 10.85 in the control group, 64.69 ± 3.23 in rats with laparotomy without removing the ovaries, 51.30 ± 6.84 in rats with laparotomy and removing the ovaries, 52.7 ± 7.18 in ovariectomized rats that received sesame oil as vehicle, and 59.2 ± 4.91, in the soy groups. Therefore, estradiol significantly increased the clonic seizure threshold, while the alcoholic extract of soy had no effect.
Conclusions: We concluded that the chronic administration of estradiol has an anticonvulsant effect in the animal model. However, alcoholic extract of soy has no effect on the onset of clonic seizures
Celecoxib as an Adjuvant to Fluvoxamine in Moderate to Severe Obsessive-compulsive Disorder: A Double-blind, Placebo-controlled, Randomized Trial
Introduction: A growing body of evidence implicates inflammatory cascades in the pathophysiology of obsessive-compulsive disorder (OCD), making this pathway a target for development of novel treatments. Methods: 50 outpatients with moderate to severe OCD participated in the trial, and underwent 10 weeks of treatment with either celecoxib (200 mg twice daily) or placebo as an adjuvant to fluvoxamine. Participants were investigated using Yale-Brown Obsessive Compulsive Scale (Y-BOCS). The main outcome measure was to assess the efficacy of celecoxib in improving the OCD symptoms. Results: General linear model repeated measures demonstrated significant effect for time � treatment interaction on the Y-BOCS total scores F (1.38, 66.34)=6.91, p=0.005. Kaplan-Meier estimation with log-rank test demonstrated significantly more rapid response in the celecoxib group than the placebo group (p<0.001). There was no significant difference in adverse event frequencies between the groups. Discussion: The results of the current study suggest that celecoxib could be a tolerable and effective adjunctive treatment for more rapid and more satisfying improvements in OCD symptoms. © Georg Thieme Verlag KG Stuttgart, New York
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