44 research outputs found
Hamiltonian formulation of systems with linear velocities within Riemann-Liouville fractional derivatives
The link between the treatments of constrained systems with fractional
derivatives by using both Hamiltonian and Lagrangian formulations is studied.
It is shown that both treatments for systems with linear velocities are
equivalent.Comment: 10 page
Hamilton-Jacobi quantization of singular Lagrangians with linear velocities
In this paper, constrained Hamiltonian systems with linear velocities are
investigated by using the Hamilton-Jacobi method. We shall consider the
integrablity conditions on the equations of motion and the action function as
well in order to obtain the path integral quantization of singular Lagrangians
with linear velocities.Comment: late
Analysis of correction methods for ships' measured speed during sea trials
For all new ships sea trials should be carried out as a part of the delivery from the yard to the ship owner. An important part of the delivery sea trial is to determine the speed capability of the ship in the contractual condition, which is traditionally deep, calm water and no wind, at some specified loading condition. However, it is seldom possible to perform this particular test under such conditions, and when the test is done in other conditions, the result is corrected back to the contractual condition. The correction can be of a significant magnitude. The correction procedure can be influenced by different parameters such as wind resistance, shallow water effect, sea currents and added resistance due to diffraction. There are different experimental methods for correction of measured speed. Since the latter parameter is the most important between others, in this article added resistance due to diffraction has been calculated for three ships using existing methods and comparisoned with the speed correction result of shipbuilder company (Hyundai Heavy Industries). The results show considerable deviation between HHI sea trial speed correction method and other methods. So HHI added resistance calculation method needs to be revised
Entropy as a function of Geometric Phase
We give a closed-form solution of von Neumann entropy as a function of
geometric phase modulated by visibility and average distinguishability in
Hilbert spaces of two and three dimensions. We show that the same type of
dependence also exists in higher dimensions. We also outline a method for
measuring both the entropy and the phase experimentally using a simple
Mach-Zehnder type interferometer which explains physically why the two concepts
are related.Comment: 19 pages, 7 figure
AmnioQuick® Duo+ for diagnosis of premature fetal membranes rupture
Background: Failure to identify women with premature fetal membranes rupture associated with infectious morbidities. Evaluation of the accuracy of AmnioQuick® Duo+ in diagnosing premature fetal membranes rupture compared to conventional diagnostic tests was the aim of this study.Methods: 220 pregnant women ≥37 and <39 weeks` gestation studied and classified into two groups; study group (premature fetal membranes rupture) and control group (no premature fetal membranes rupture). Participants examined by trans-abdominal ultrasound (TAS) and vaginal speculum to visualize amnion leaking and for collection of samples for fern, nitrazine and AmnioQuick® Duo+ tests on admission. A final diagnosis whether the studied women had PROM or not at the initial presentation made after delivery.Results: Sensitivity and specificity of the AmnioQuick® Duo+ to diagnose PROM was 93.6% and 86.4%; respectively compared with 72.7% and 80.9%; respectively for fern test and 76.4% and 83.6%; respectively for nitrazine test. Positive predictive value, negative predictive value and accuracy of AmnioQuick® Duo+ to detect PROM were 87.3%, 93.1% and 90%; respectively compared with 79.2%, 74.8% and 76.8%; respectively for fern test and 82.4%, 77.97% and 80%; respectively for nitrazine test. AmnioQuick® Duo+ test had higher accuracy to detect premature fetal membranes rupture compared to conventional diagnostic tests.Conclusions: AmnioQuick® Duo+ is accurate bedside immunoassay test, better than the individual conventional diagnostic tests and can used as complementary test to improve the management of women with women premature fetal membranes rupture
Quantum Particle-Trajectories and Geometric Phase
"Particle"-trajectories are defined as integrable paths
in projective space.
Quantum states evolving on such trajectories, open or closed, do not
delocalise in projection, the phase associated with the trajectories
being related to the geometric (Berry) phase and the Classical Mechanics
action. High Energy Physics properties of states evolving on
"particle"-trajectories are discussed.Comment: 4 page
Off-Diagonal Geometric Phases
We investigate the adiabatic evolution of a set of non-degenerate eigenstates
of a parameterized Hamiltonian. Their relative phase change can be related to
geometric measurable quantities that extend the familiar concept of Berry phase
to the evolution of more than one state. We present several physical systems
where these concepts can be applied, including an experiment on microwave
cavities for which off-diagonal phases can be determined from published data.Comment: 5 pages 2 figures - RevTeX. Revised version including geometrical
interpretatio
Titrated Misoprostol Versus Dinoprostone for Labor Induction
Background: Misoprostol is as effective as dinoprostone for labor induction with low cost and temperature stability.Aim: This study designed to compare titrated misoprostol regarding its safety and efficacy with dinoprostone for induction of labor.Subjects and Methods: Women with a single pregnancy, above 37 weeks’ gestation, cephalic presentation, modified Bishop’s score <8, and not in labor with reassuring fetal heart rate, admitted for labor induction enrolled in this randomized controlled study. Studied women were randomized into; Group I: received oral misoprostol titrated in sterile water (200 μg tablet was dissolved in 200 ml sterile water [1 μg/ml]), starting dose of 20 μg misoprostol required, given every 2 h, and stopped if adequate contractions obtained and Group II: received vaginal dinoprostone tablet maximum two doses followed by augmentation of labor by oxytocin ± amniotomy if there is no uterine contractions after two doses of dinoprostone. In Group I, if the contractions were inadequate after two doses of oral titrated misoprostol (20 μg [20 ml]), the starting dose increased to 40 μg (40 ml), escalating the dose from 5 to 10 ml (45–50 μg), and 20 ml (60 μg) maximum ± amniotomy. If the uterine contractions were adequate, the next dose of misoprostol or dinoprostone was omitted. Statistical analysis done using Student’s t‑test for quantitative data and Chi‑square test for qualitative data.Results: Induction‑to‑delivery time was significantly longer in misoprostol than dinoprostone group (975 vs. 670 min, respectively), (P = 0.01). About 20.2% (21/104) of women in misoprostol group did not deliver vaginally within 24 h compared to 7.4% (8/108) in dinoprostone group (significant difference, P = 0.01). Augmentation of labor was significantly high in dinoprostone (37.96% [41/108]) compared to misoprostol group (10.6% [11/104]) (P < 0.01).Conclusion: Titrated misoprostol for induction of labor seems to be associated with significantly longer induction‑to‑delivery time, low incidence of vaginal birth within 24 h, and less need for augmentation of labor compared to vaginal dinoprostone.KEY WORDS: Dinoprostone, labor induction, titrated misoprosto