13,896 research outputs found
Three-point Green function of massless QED in position space to lowest order
The transverse part of the three-point Green function of massless QED is
determined to the lowest order in position space. Taken together with the
evaluation of the longitudinal part in arXiv:0803.2630, this gives a relation
for QED which is analogous to the star-triangle relation. We relate our result
to conformal-invariant three-point functions.Comment: 8 page
Complex fermion mass term, regularization and CP violation
It is well known that the CP violating theta term of QCD can be converted to
a phase in the quark mass term. However, a theory with a complex mass term for
quarks can be regularized so as not to violate CP, for example through a zeta
function. The contradiction is resolved through the recognition of a dependence
on the regularization or measure. The appropriate choice of regularization is
discussed and implications for the strong CP problem are pointed out.Comment: REVTeX, 4 page
Fertility and early pregnancy outcomes after treatment for cervical intraepithelial neoplasia: systematic review and meta-analysis
OBJECTIVE:
To determine the impact of cervical excision for cervical intraepithelial neoplasia on fertility and early pregnancy outcomes.
DESIGN:
Systematic review and meta-analysis of cohort studies.
DATA SOURCES:
Medline and Embase.
ELIGIBILITY CRITERIA:
Studies assessing fertility and early pregnancy outcomes in women with a history of treatment for cervical intraepithelial neoplasia versus untreated women. We classified the included studies according to treatment type and fertility or early pregnancy endpoint.
ANALYSIS:
Pooled relative risks and 95% confidence intervals using a random effect model, and interstudy heterogeneity with I(2) statistics.
RESULTS:
15 studies fulfilled the inclusion criteria and were included. The meta-analysis did not provide any evidence that treatment for cervical intraepithelial neoplasia adversely affected the chances of conception. The overall pregnancy rate was higher for treated women than for untreated women (four studies; 43% v 38%, pooled relative risk 1.29, 95% confidence interval 1.02 to 1.64), although the heterogeneity between studies was high (P<0.0001). Pregnancy rates did not differ between women with an intention to conceive (two studies; 88% v 95%, 0.93, 0.80 to 1.08) and the number requiring more than 12 months to conceive (three studies, 15% v 9%, 1.45, 0.89 to 2.37). Although the rates for total miscarriages (10 studies; 4.6% v 2.8%, 1.04, 0.90 to 1.21) and miscarriage in the first trimester (four studies; 9.8% v 8.4%, 1.16, 0.80 to 1.69) was similar for treated and untreated women, cervical treatment was associated with a significantly increased risk of miscarriage in the second trimester. The rate was higher for treated women than for untreated women (eight studies; 1.6% v 0.4%, 16,558 women; 2.60, 1.45 to 4.67). The number of ectopic pregnancies (1.6% v 0.8%; 1.89, 1.50 to 2.39) and terminations (12.2% v 7.4%; 1.71, 1.31 to 2.22) was also higher for treated women.
CONCLUSION:
There is no evidence suggesting that treatment for cervical intraepithelial neoplasia adversely affects fertility, although treatment was associated with a significantly increased risk of miscarriages in the second trimester. Research should explore mechanisms that may explain this increase in risk and stratify the impact that treatment may have on fertility and early pregnancy outcomes by the size of excision and treatment method used
Cosmological Symmetry Breaking, Pseudo-scale invariance, Dark Energy and the Standard Model
The energy density of the universe today may be dominated by the vacuum
energy of a slowly rolling scalar field. Making a quantum expansion around such
a time dependent solution is found to break fundamental symmetries of quantum
field theory. We call this mechanism cosmological symmetry breaking and argue
that it is different from the standard phenomenon of spontaneous symmetry
breaking. We illustrate this with a toy scalar field theory, whose action
displays a U(1) symmetry. We identify a symmetry, called pseudo-scale
invariance, which sets the cosmological constant exactly equal to zero, both in
classical and quantum theory. This symmetry is also broken cosmologically and
leads to a nonzero vacuum or dark energy. The slow roll condition along with
the observed value of dark energy leads to a value of the background scalar
field of the order of Planck mass. We also consider a U(1) gauge symmetry
model. Cosmological symmetry breaking, in this case, leads to a non zero mass
for the vector field. We also show that a cosmologically broken pseudo-scale
invariance can generate a wide range of masses.Comment: 18 pages, no figure
The Risk of Awkward Posture with the Incidence of Work-related Musculoskeletal Disorders (WMSDs) in Massage Therapist
Many massage therapists experience work-related skeletal muscle disorders (WMSDs). This study aimed to determine the proportion of the incidence of WMSDs and the relationship with the incident of posture WMSDs in massage therapists. The type of research was quantitative analytic observational with cross sectional design. The type of massage under study was traditional massage. Population and sample were massage therapist in Pekanbaru City 2017 with sample size 77 people taken by consecutive sampling technique. Data collection and processing used interviews with quesonnaires, documentation and Rapid Upper Limb Assesment (RULA). Level of risk of WMSDs incident used semi-qualitave analysis and nordic body map. WMSDs incidence rate in massage therapist was high enough that was 61%. The results showed that the variables significantly correlated with incidence of WMSDs were odd posture (POR: 8,30, 95% CI: 2,401-8,753), length of work (POR: 10,109; 95% CI:2,567-39,811) and age (POR: 7,649 95% CI: 2,567-39,811). The most WMSDs complaints on both hands were 57 people (74%), left shoulder and right shoulder were 27 people (35.1%) and lower back were 19 (24,7%). It is advisable in massage therapists to avoid awkward posture while massaging clients by improving work posture, posion while massaging and placing the equipment used within the reach of the hand. 
Utensils-The Major Non-Ferrous Industry of India
Aluminium and brass domestic utensils are major products of the Indian non- ferrous industry amounting to 80 per cent of the total consumption of these metals in India. The utensils industry is thus a much more significant part of the non-ferrous metal industry in India than elsewhere in the world. The annual production of brass utensils is
over 40,000 tons, of which only 7000 tons are produced
in registered factories , the balance being manufactured by the cottage industries. Aluminium utensils, on the other hand, are mostly manufactured in factories, the annual production being estimated at over 12,000 tons . India is an exporter of aluminium wares and utensils ( 978 tons worth Rs. 61 lakhs in 1951 ) and brass wares and
utensils ( worth Rs. 35 lakhs in 1951 ) mostly to the East African, Middle Eastern and South Asian countries.
Production of aluminium and copper in India is not able at present to meet the demands of industry and has to be augmented by imports to the tune of Rs. 750 lakhs ( including zinc). Aluminium is the only non-ferrous metal production of which can be readily increased to any large extent in India ; this is being organized under the country's first Five Year Plan. From the point of view of
national economics it is necessary that for utensils
copper alloys be replaced by aluminium and its alloys in so far as this can be done without any prejudice to the indigenous manufacture of copper.This replacement could be easily effected if conservatism and antipathy of consumers against aluminium utensils could be eradicated by suitable
publicity accompanied by improved design and manufacture of aluminium utensils. The need for technical control and standardization is emphasized
Domain wall dynamics in integrable and chaotic spin-1/2 chains
We study the time evolution of correlation functions, spin current, and local
magnetization in an isolated spin-1/2 chain initially prepared in a sharp
domain wall state. The results are compared with the level of spatial
delocalization of the eigenstates of the system which is measured using the
inverse participation ratio. Both integrable and non-integrable regimes are
considered. Non-integrability is introduced to the integrable Hamiltonian with
nearest neighbor couplings by adding a single site impurity field or by adding
next-nearest-neighbor couplings. A monotonic correspondence between the
enhancement of the level of delocalization, spin current and magnetization
dynamics occurs in the integrable domain. This correspondence is however lost
for chaotic models with weak Ising interactions.Comment: 9 pages, 5 figures, 1 tabl
Improving the efficiency of the detection of gravitational wave signals from inspiraling compact binaries: Chebyshev interpolation
Inspiraling compact binaries are promising sources of gravitational waves for
ground and space-based laser interferometric detectors. The time-dependent
signature of these sources in the detectors is a well-characterized function of
a relatively small number of parameters; thus, the favored analysis technique
makes use of matched filtering and maximum likelihood methods. Current analysis
methodology samples the matched filter output at parameter values chosen so
that the correlation between successive samples is 97% for which the filtered
output is closely correlated. Here we describe a straightforward and practical
way of using interpolation to take advantage of the correlation between the
matched filter output associated with nearby points in the parameter space to
significantly reduce the number of matched filter evaluations without
sacrificing the efficiency with which real signals are recognized. Because the
computational cost of the analysis is driven almost exclusively by the matched
filter evaluations, this translates directly into an increase in computational
efficiency, which in turn, translates into an increase in the size of the
parameter space that can be analyzed and, thus, the science that can be
accomplished with the data. As a demonstration we compare the present "dense
sampling" analysis methodology with our proposed "interpolation" methodology,
restricted to one dimension of the multi-dimensional analysis problem. We find
that the interpolated search reduces by 25% the number of filter evaluations
required by the dense search with 97% correlation to achieve the same
efficiency of detection for an expected false alarm probability. Generalized to
higher dimensional space of a generic binary including spins suggests an order
of magnitude increase in computational efficiency.Comment: 23 pages, 5 figures, submitted to Phys. Rev.
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