The Chern-Simons diffusion rate in strongly coupled N=4 SYM plasma in an external magnetic field

We calculate the Chern-Simons diffusion rate in a strongly coupled N=4 SUSY Yang-Mills plasma in the presence of a constant external $U(1)_R$ magnetic flux via the holographic correspondence. Due to the strong interactions between the charged fields and non-Abelian gauge fields, the external Abelian magnetic field affects the thermal Yang-Mills dynamics and increases the diffusion rate, regardless of its strength. We obtain the analytic results for the Chern-Simons diffusion rate both in the weak and strong magnetic field limits. In the latter limit, we show that the diffusion rate scales as $B\times T^2$ and this can be understood as a result of a dynamical dimensional reduction.Comment: 10 pages, 1 figure, typos corrected, comments adde

Factors affecting site-specific response analysis

The engineering purpose of a site-specific response analysis is to estimate the uniform hazard acceleration spectrum on the ground surface for a selected hazard level. One of the mandatory components for site response analyses is one or more representative acceleration time histories that need to be scaled with respect to the calculated seismic hazard level for the selected site. The selection and scaling procedures of earthquake acceleration records play an important role in this approach. The effects and differences in using two different scaling approaches are studied: scaling with respect to ground motion parameters and response spectrum scaling. A set of homogeneous ground motion prediction relationships are developed for peak ground acceleration, peak ground velocity, root-mean-square acceleration, Arias intensity, cumulative absolute velocity, maximum spectral acceleration, response spectrum intensity, and acceleration spectrum intensity based on a uniform set of acceleration records for ground motion parameter scaling. The uncertainties associated with site response analysis are considered as epistemic and aleatory uncertainties in source characteristics, soil profile, and soil properties. Aleatory variability is due to the intrinsic randomness of natural systems; it cannot be reduced with additional data (Passeri et al. 2020), however; its variability may be modeled by probability distribution functions. Thus, one possibility is to determine the probability distribution of the acceleration spectrum calculated on the ground surface for all possible input acceleration records, site profiles, and dynamic soil properties. The variability in the earthquake source and path effects are considered using a large number of acceleration records compatible with the site-dependent earthquake hazard in terms of fault mechanism, magnitude, and distance range recorded on stiff site conditions. Likewise, a large number of soil profiles may be considered to account for the site condition variability. The uncertainties related to dynamic soil properties may be considered as possible variability of maximum dynamic shear modulus in site response analyses. A methodology is proposed to estimate a uniform hazard acceleration spectrum on the ground surface based on the probabilistic assessment of the factors involved in site response analysis. The uniform hazard acceleration spectra obtained from a case study are compared with the spectra calculated by probabilistic models proposed in the literature.WOS:000743801200001Scopus - Affiliation ID: 60105072Science Citation Index ExpandedQ1-Q2Article; Early AccessUluslararası işbirliği ile yapılmayan - HAYIROcak2022YÖK - 2021-22Oca

Risk factors associated with post-traumatic stress symptoms following childbirth in Turkey

OBJECTIVE: this study examined factors associated with symptoms of post-traumatic stress (PTS) following childbirth in women with normal, low-risk pregnancies in Nigde, Turkey. DESIGN: a prospective longitudinal design where women completed questionnaire measures at 20+ weeks' gestation and 6-8 weeks after birth. SETTING: eligible pregnant women were recruited from nine family healthcare centres in Nigde between September 2013 and July 2014. PARTICIPANTS: a total of 242 women completed questionnaires at both time points. MEASURES: PTS symptoms were measured using the Impact of Event Scale-Revised (IES-R) 6-8 weeks after birth. Potential protective or risk factors of childbirth self-efficacy, fear of childbirth, adaptation to pregnancy/motherhood, and perceived social support were measured in pregnancy and after birth. Perceived support and control during birth was measured after birth. Demographic and obstetric information was collected in pregnancy using standard self-report questions. FINDINGS: PTS symptoms were associated with being multiparous, having a planned pregnancy, poor psychological adaptation to pregnancy, higher outcome expectancy but lower efficacy expectancy during pregnancy, urinary catheterization during labour, less support and perceived control in birth, less satisfaction with hospital care, poor psychological adaptation to motherhood and increased fear of birth post partum. Regression analyses showed the strongest correlates of PTS symptoms were high outcome and low efficacy expectancies in pregnancy, urinary catheterization in labour, poor psychological adaptation to motherhood and increased fear of birth post partum. This model accounted for 29% of the variance in PTS symptoms. CONCLUSIONS: this study suggests women in this province in Turkey report PTS symptoms after birth and this is associated with childbirth self-efficacy in pregnancy, birth factors, and poor adaptation to motherhood and increased fear of birth post partum. IMPLICATIONS FOR PRACTICE: maternity care services in Turkey need to recognise the potential impact of birth experiences on women's mental health and adaptation after birth. The importance of self-efficacy in pregnancy suggests antenatal education or support may protect women against developing post partum PTS, but this needs to be examined further

Synthesis and structural characterization of trans-bis[1,3-bis(methoxy- ethyl)-4,5-bis(2,4,6-trimethylphenyl)imidazolidin-2-ylidene]dichloro- palladium(II)

A Pd(II) complex of a new N-heterocyclic carbene (NHC) ligand with bulky substituents and functionalized methoxy-donor side arms has been synthesized and characterized by elemental analyses, 1H and 13C NMR, and IR spectroscopy. Molecular and crystal structures of the title complex have been determined by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/c, with a = 15.927(2), b = 8.489(2), c = 20.309(5) Å, β = 99.213(2)°, Z = 2, Dx = 1.253 g cm-3. The palladium atom is situated on an inversion center. There are several weak intramolecular C-H⋯N/O interactions. © 2007 Verlag der Zeitschrift für Naturforschung

The assessment of the knowledge and awareness about glaucoma in glaucoma patients and general population: a sample from Turkey

Background: The study aimed to evaluate the level of knowledge and awareness of glaucoma and their possible determinants in a group of people diagnosed with glaucoma and in a population based group without glaucoma.Methods: The study included people with an age range of 40 to 80years; 410 patients without glaucoma who admitted to primary health care service and 113 patients who admitted to hospitals with diagnosis of glaucoma. In addition to Glaucoma Knowledge Level Questionnaire (GKLQ), participants were asked about their socio-demographic characteristics, level of awareness and resources of the information about glaucoma. Multivariate logistic regression and multiple linear regression analyses were used to assess the variants which have impact on the level of the awareness about glaucoma and to evaluate the factors effective on the score of GKLQ, respectively.Results: The ratio of awareness about glaucoma was found to be 64.1% in people without glaucoma. The knowledge and awareness about glaucoma were found to be higher in glaucoma patients compared to healthy people but not at a desired level. The education level was the only factor effecting both awareness and knowledge about glaucoma.Conclusions: As awareness about glaucoma can lead to early detection, the assessment of the knowledge and awareness about glaucoma is very important in terms of disease prevention. Health education and preventive health care services should be programmed including for both glaucoma patients and healthy people based on the level of their education

Holographic Pomeron and the Schwinger Mechanism

We revisit the problem of dipole-dipole scattering via exchanges of soft Pomerons in the context of holographic QCD. We show that a single closed string exchange contribution to the eikonalized dipole-dipole scattering amplitude yields a Regge behavior of the elastic amplitude; the corresponding slope and intercept are different from previous results obtained by a variational analysis of semi-classical surfaces. We provide a physical interpretation of the semi-classical worldsheets driving the Regge behavior for (-t)>0 in terms of worldsheet instantons. The latter describe the Schwinger mechanism for string pair creation by an electric field, where the longitudinal electric field E_L=\sigma_T tanh(\chi/2) at the origin of this non-perturbative mechanism is induced by the relative rapidity {\chi} of the scattering dipoles. Our analysis naturally explains the diffusion in the impact parameter space encoded in the Pomeron exchange; in our picture, it is due to the Unruh temperature of accelerated strings under the electric field. We also argue for the existence of a "micro-fireball" in the middle of the transverse space due to the soft Pomeron exchange, which may be at the origin of the thermal character of multiparticle production in ep/pp collisions. After summing over uncorrelated multi-Pomeron exchanges, we find that the total dipole-dipole cross section obeys the Froissart unitarity bound.Comment: 17 pages, 4 figures, version 2: minor typos corrected, references adde

A Gauge-Gravity Relation in the One-loop Effective Action

We identify an unusual new gauge-gravity relation: the one-loop effective action for a massive spinor in 2n dimensional AdS space is expressed in terms of precisely the same function [a certain multiple gamma function] as the one-loop effective action for a massive charged scalar in 4n dimensions in a maximally symmetric background electromagnetic field [one for which the eigenvalues of F_{\mu\nu} are maximally degenerate, corresponding in 4 dimensions to a self-dual field, equivalently to a field of definite helicity], subject to the identification F^2 \Lambda, where \Lambda is the gravitational curvature. Since these effective actions generate the low energy limit of all one-loop multi-leg graviton or gauge amplitudes, this implies a nontrivial gauge-gravity relation at the non-perturbative level and at the amplitude level.Comment: 6 page

Effect of photoperiod and host distribution on the horizontal transmission of Isaria fumosorosea (Hypocreales: Cordycipitaceae) in greenhouse whitefly assessed using a novel model bioassay

A model bioassay was used to evaluate the epizootic potential and determine the horizontal transmission efficiency of Isaria fumosorosea Trinidadian strains against Trialeurodes vaporariorum pharate adults under optimum conditions (25±0.5°C, ~100% RH) at two different photoperiods. Untreated pharate adults were arranged on laminated graph paper at different distributions to simulate varying infestation levels on a leaf surface. Four potential hosts were located 7, 14 and 21 mm away from a central sporulating cadaver simulating high, medium and low infestation levels, respectively. Percent hosts colonized were recorded 7, 12, 14 and 21 days post-treatment during a 16- and 24-h photophase. After 21 days, mean percent hosts colonized at the highest, middle and lowest infestation levels were 93 and 100%, 22 and 58%, 25 and 39% under a 16- and 24-h photophase, respectively. From the results, it was concluded that the longer the photophase, the greater the percentage of hosts colonized, and as host distance increased from the central sporulating cadaver, colonization decreased. The use of this novel model bioassay technique is the first attempt to evaluate the epizootic potential and determine the horizontal transmission efficiency of I. fumosorosea Trinidadian strains under optimal environmental conditions at different photoperiods. This bioassay can be used to assess horizontal transmission efficiency for the selection of fungi being considered for commercial biopesticide development