13,896 research outputs found

    Three-point Green function of massless QED in position space to lowest order

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    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

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    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

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    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

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    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

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    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.&nbsp

    Utensils-The Major Non-Ferrous Industry of India

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    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

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    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

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    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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