475 research outputs found
Effect of nitric oxide donors on uterine and sub-endometrial blood flow in patients with unexplained infertility: a randomized controlled trial
Background: Impaired sub-endometrial perfusion might reduce endometrial receptivity and possibly contribute to unexplained infertility. A favorable effect on sub-endometrial blood flow has been demonstrated with nitric oxide.Methods: This randomized controlled trial evaluated the effect of nitroglycerine on uterine and sub-endometrial blood flow in women with unexplained infertility. Sixty women were randomized into 2 equal groups. The study group received 5mg nitroglycerine patch daily from day 2 of the cycle till the evaluation day and the control group received no treatment. Independent of the study arms, 30 parous women were included as the fertile group. Six to eight days after detecting luteinizing hormone surge, women were assessed for endometrial thickness, uterine artery blood flow with color Doppler and sub-endometrial blood flow with three-dimensional power Doppler.Results: Compared to fertile women, cases with unexplained infertility (control group) had a significantly thinner endometrium, higher uterine artery Doppler indices and lower sub-endometrial blood flow. Women who received nitroglycerin showed a significant improvement in sub-endometrial blood flow while uterine artery blood flow did not show a significant difference; however, the values were also comparable to fertile women. In addition, no effect on endometrial thickness was found with nitroglycerin treatment. Nitroglycerin treatment side effects were headache, blurring of vision and hypotension. These adverse effects were not significant compared to controls.Conclusions: In women with unexplained infertility, nitroglycerin significantly improved the sub-endometrial blood flow but did not affect the endometrial thickness
Extended Absolute Parallelism Geometry
In this paper, we study Absolute Parallelism (AP-) geometry on the tangent
bundle of a manifold . Accordingly, all geometric objects defined in
this geometry are not only functions of the positional argument , but also
depend on the directional argument . Moreover, many new geometric objects,
which have no counterpart in the classical AP-geometry, emerge in this
different framework. We refer to such a geometry as an Extended Absolute
Parallelism (EAP-) geometry. The building blocks of the EAP-geometry are a
nonlinear connection assumed given a priori and linearly independent
vector fields (of special form) defined globally on defining the
parallelization. Four different -connections are used to explore the
properties of this geometry. Simple and compact formulae for the curvature
tensors and the W-tensors of the four defined -connections are obtained,
expressed in terms of the torsion and the contortion tensors of the EAP-space.
Further conditions are imposed on the canonical -connection assuming that it
is of Cartan type (resp. Berwald type). Important consequences of these
assumptions are investigated. Finally, a special form of the canonical
-connection is studied under which the classical AP-geometry is recovered
naturally from the EAP-geometry. Physical aspects of some of the geometric
objects investigated are pointed out and possible physical implications of the
EAP-space are discussed, including an outline of a generalized field theory on
the tangent bundle of Comment: 27 pages, LaTeX-file, The last version of this paper was replaced by
mistake (by arXiv: 0905.0209[gr-qc]
Maximizing irrigation water use and crop productivity under mulching with geotextile for lettuce plants (Lactuca sativa L. var. capitata)
One of the fields that will be negatively impacted by climate change is agriculture, particularly in developing countries. Most crops are affected when grown under limited water supplies as it produces low productivity, especially during the late growing stage. For this reason, it is important to improve irrigation efficiency and crop yield. Two successive seasons were conducted during 2021 and 2022 to test the action of mulching types on iceberg lettuce plants (Lactuca sativa L. var. capitata) with irrigation stress. In the sandy loam soil conditions of the El Sharkia Governorate in Belbeis, Egypt, iceberg lettuce plants were grown with different types of mulching (no mulching, white geotextile sheet, and black plastic sheet) under varying levels of water (100, 80, and 60% of ETc, or evapotranspiration). Results showed that mulching the soil surface with plastic and geotextile produced the highest data of soil moisture content inside the root zoon. In conclusion, compared to the control (no mulching), all mulching types treatments result in a significant increase in yield parameters. In this study, however, mulching with white geotextile sheets and requiring 100% ETc irrigation proved to be the statistically most effective treatment, while 80% ETc combined with white geotextile sheet get values were statistically equal to the results with the control (100% ETc without mulching). It is possible to achieve results similar yield to the control or better, while saving an amount of irrigation water of up to 20% by using ETo 80 % combined with mulching with white geotextile sheet without any negative effect on the plant. However, it can be recommended to use geotextile compared to black plastic, as plastic requires more time to degrade, which will be harmful to the environment
Teleparallel Lagrange Geometry and a Unified Field Theory
In this paper, we construct a field theory unifying gravity and
electromagnetism in the context of Extended Absolute Parallelism (EAP-)
geometry. This geometry combines, within its structure, the geometric richness
of the tangent bundle and the mathematical simplicity of Absolute Parallelism
(AP-) geometry. The constructed field theory is a generalization of the
Generalized Field Theory (GFT) formulated by Mikhail and Wanas. The theory
obtained is purely geometric. The horizontal (resp. vertical) field equations
are derived by applying the Euler-Lagrange equations to an appropriate
horizontal (resp. vertical) scalar Lagrangian. The symmetric part of the
resulting horizontal (resp. vertical) field equations gives rise to a
generalized form of Einstein's field equations in which the horizontal (resp.
vertical) energy-momentum tensor is purely geometric. The skew-symmetric part
of the resulting horizontal (resp. vertical) field equations gives rise to a
generalized form of Maxwell equations in which the electromagnetic field is
purely geometric. Some interesting special cases, which reveal the role of the
nonlinear connection in the obtained field equations, are examined. Finally,
the condition under which our constructed field equations reduce to the GFT is
explicitly established.Comment: Latex file, 33 page
Search for R-parity Violating Supersymmetry in Dimuon and Four-Jets Channel
We present results of a search for R-parity-violating decay of the neutralino
chi_1^0, taken to be the Lightest Supersymmetric Particle. It is assumed that
this decay proceeds through one of the lepton-number violating couplings
lambda-prime_2jk (j=1,2; k=1,2,3). This search is based on 77.5 pb-1 of data,
collected by the D0 experiment at the Fermilab Tevatron in ppbar collisions at
a center of mass energy of 1.8 TeV in 1992-1995.Comment: 10 pages, 3 figure
Improved W boson mass measurement with the D0 detector
We have measured the W boson mass using the D0 detector and a data sample of
82 pb^-1 from the Tevatron collider. This measurement used W -> e nu decays,
where the electron is close to a boundary of a central electromagnetic
calorimeter module. Such 'edge' electrons have not been used in any previous D0
analysis, and represent a 14% increase in the W boson sample size. For these
electrons, new response and resolution parameters are determined, and revised
backgrounds and underlying event energy flow measurements are made. When the
current measurement is combined with previous D0 W boson mass measurements, we
obtain M_W = 80.483 +/- 0.084 GeV. The 8% improvement from the previous D0
measurement is primarily due to the improved determination of the response
parameters for non-edge electrons using the sample of Z bosons with non-edge
and edge electrons.Comment: submitted to Phys. Rev. D; 20 pages, 18 figures, 9 table
Direct Search for Charged Higgs Bosons in Decays of Top Quarks
We present a search for charged Higgs bosons in decays of pair-produced top
quarks in pbar p collisions at sqrt(s) = 1.8 TeV using 62.2 pb^-1 of data
recorded by the D0 detector at the Fermilab Tevatron collider. No evidence is
found for signal, and we exclude at 95% confidence most regions of the (M
higgs, tan beta) parameter space where the decay t->H b has a branching
fraction greater than 0.36 and B(H -> tau nu) is large.Comment: 11 pages, 4 figures, submitted to Phys. Rev. Let
Study of CP violation in Dalitz-plot analyses of B0 --> K+K-KS, B+ --> K+K-K+, and B+ --> KSKSK+
We perform amplitude analyses of the decays , , and , and measure CP-violating
parameters and partial branching fractions. The results are based on a data
sample of approximately decays, collected with the
BABAR detector at the PEP-II asymmetric-energy factory at the SLAC National
Accelerator Laboratory. For , we find a direct CP asymmetry
in of , which differs
from zero by . For , we measure the
CP-violating phase .
For , we measure an overall direct CP asymmetry of
. We also perform an angular-moment analysis of
the three channels, and determine that the state can be described
well by the sum of the resonances , , and
.Comment: 35 pages, 68 postscript figures. v3 - minor modifications to agree
with published versio
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