30,553 research outputs found
Prenatal detection of esophageal atresia: A systematic review and meta-analysis
No full textIntroduction: The primary aim of this systematic review was to quantify the diagnostic performance of ultrasound, magnetic resonance imaging and amniotic fluid analysis in detecting esophageal atresia prenatally. The secondary aim was to explore the accuracy of individual imaging signs in identifying this anomaly. Material and methods: MEDLINE, Embase and Cochrane databases were searched. The quality of studies was assessed using the revised tool for the quality assessment of diagnostic accuracy studies. Summary estimates of sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio for the predictive accuracy of ultrasound, magnetic resonance imaging and amniotic fluid analysis in detecting esophageal atresia were computed using the hierarchical summary receiver operating characteristic or DerSimonian-Laird random-effect model, according to the number of studies included in each analysis. PROSPERO registration number: CRD42017055828. Results: Twenty studies (73 246 fetuses, 1760 affected by esophageal atresia) were included. Overall, prenatal ultrasound had a sensitivity of 31.7%. Only two studies reported all data for diagnostic accuracy; based on these studies, prenatal ultrasound had a sensitivity of 41.9%, a specificity of 99.9%, a positive likelihood ratio of 88.1, a negative likelihood ratio of 0.58 and a diagnostic odds ratio of 153.7. Prenatal ultrasound correctly identified 77.9% of cases with esophageal atresia and 21.9% esophageal atresia with an associated tracheo-esophageal fistula. Polyhydramnios was present in 56.3% of cases affected by esophageal atresia, and a small or absent stomach was identified in 50.0% cases. When performed following a suspicious ultrasound, fetal magnetic resonance imaging had an good overall diagnostic accuracy for esophageal atresia, with a sensitivity of 94.7%, a specificity of 89.3%, a positive likelihood ratio of 8.8, a negative likelihood ratio of 0.06 and a diagnostic odds ratio of 149.3. Finally, amniotic fluid analysis with an esophageal atresia index ≥3 had a sensitivity of 89.9% and a specificity of 99.6% in detecting esophageal atresia. Conclusions: Ultrasound alone is a poor diagnostic tool for identifying esophageal atresia prenatally, and has a high rate of false positive diagnoses. Magnetic resonance imaging and amniotic fluid analysis have high diagnostic accuracy for esophageal atresia. We would recommend their use following a suspicious ultrasound. © 2019 Nordic Federation of Societies of Obstetrics and Gynecolog
Institutional reform in emerging securities markets
Get PDFIn the long run, sound, efficient securities markets can contribute to economic growth; in the short run, they play an important role in financial liberalization. The author provides a guide to issues involved in institutional and regulatory reform of securities markets - and a discussion of the practical implications of different policy options and sequencing decisions. He argues that establishing sound securities markets requires institutional development that is a substantial task for many developing countries. Prerequisities for the development of securities markets include: (a) a macroeconomic and fiscal environment conducive to the supply of quality securities; (b) a legal, regulatory, and institutional infrastructure that can support efficient operation of the securities market. Essentially such an infrastructure must provide four things: (a) certainty about property rights and contracts; (b) transparent trading and other procedures and public disclosure by companies of all information relevant to the value of their securities; (c) protection against unfair practices by insiders and intermediaries; and (d) protection against the financial failure of intermediaries and market institutions such as clearinghouses. The author also provides examples of the policy conflicts and uncertainties that are routine in securities market reform and development, and suggests approaches to managing them.Financial Intermediation,Environmental Economics&Policies,Insurance&Risk Mitigation,Banks&Banking Reform,Economic Theory&Research
Erratum to: Effect of moderate red wine intake on cardiac prognosis after recent acute myocardial infarction of subjects with Type 2 diabetes mellitus (Diabetic Medicine, (2006), 23, 9, (974-981), 10.1111/j.1464-5491.2006.01886.x)
No full textIn an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola.In an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola
Elaboration on Kwapien's theorem: Representing bounded mean zero functions f as coboundary f = g ◦ T − g
No full textIn [8] Kwapien proved that every mean zero function f ∈ L∞[0, 1] we can write as f = g ◦ T − g for some g ∈ L∞[0, 1] and some measure preserving transformation T of [0, 1]. However, as was discovered in [4] there is a gap in the proof for the case that f is not continuous. The aim of this bachelor thesis is filling in that gap in the proof. We first extend Kwapien’s proof for continuous functions to certain other measure spaces. Thereafter, we use the method of proof suggested by Kwapien, to proof the theorem for mean zero function f ∈ L∞[0, 1] for which λ(f−1({x})) = 0 for all x ∈ R. Using this result we then proof that every mean zero function f ∈ L∞[0, 1] can be written as a sum f =(g1 ◦ T1 − g1) + (g2 ◦ T2 − g2) where g1, g2 ∈ L∞[0, 1] and where T1, T2 are measure preserving transformations of [0, 1]. We finish this thesis with an application of Kwapien’s theorem in the study to singular traces Applied Mathematic
TWO-PHOTON SPECTROSCOPY OF THE AND STATES OF
No full text Research supported by AFOSR K. Hoshiba et al. J. Phys. B 18, 1.875 (1985). T. Sakai et al., J. Phys. B. 21, 229 (1988).Author Institution: Molecular Physics Laboratory, SRI InternationalThe and states of are excited from the ground by two photons near 207 nm and detected by vuv fluorescence or by ionization by a third photon. The laser source for these measurements is an excimer-pumped dye laser operating with PBBO dye at 415 nm. This light is doubled in a crystal and focused into a cell containing a mixture of in He. The uv wavelengths were calibrated against the (3.0) band in NO, which was calibrated against in the visible. Vibrational levels were observed in the state and in the state, based on the previous electron-impact , and partially resolved rotationally (the effective excitation linewidth is ). These assignments are supported by simulations of the two-photon excitation spectra. Although the fluorescence has not yet been spectrally resolved, we believe that it arises predominantly from the triplet state even when the singlet is initially excited. In the latter case, the fluorescence is temporally delayed, and increases in intensity as the He density is increased. The two-phonon excitation scheme we have developed should be useful in investigating the kinetics of the 158 nm laser, which is believed to arise from a transition from the outer well of the state to a weakly bound state correlating to ground state atoms.$^{2}
Free product subgroups between Chevalley groups G(Φ,F) and G(Φ,F[t])
No full textAbstractWe investigate subgroups of a Chevalley group G=G(Φ,A) over a ring A, containing its elementary subgroup E=E(Φ,F) over a subring F⊆A. Assume that the root system Φ is simply laced and A=F[t] is a polynomial ring. We show that if G is of adjoint type, then there exists an element g∈E(Φ,A) such that 〈g,E(Φ,F)〉=〈g〉*E(Φ,F), where 〈X〉 denotes the subgroup, generated by a set X, and * stands for the free product.It follows that under the above assumptions the lattice L=L(E,G) is not standard. Moreover, combining the above result with theorems of Nuzhin and the author one obtains a necessary and sufficient condition for L to be standard provided that A and F are fields of characteristic not 2 and Φ≠G2
f(G,T) and its Cosmological Implications
Get PDFA coupled formulation of the Gauss-Bonnet invariant term G and the
energy momentum trace T term provide a modified f(G,T) gravity,
has been analyzed in this study. The functional form for the
f(G,T) gravity has been taken as f(G,T)=αT+ βGThe presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
b-Generalized Skew Derivations on Multilinear Polynomials in Prime Rings
No full textLet R be a prime ring of characteristic different from 2, Qr be its right Martindale quotient ring and C be its extended centroid. In this paper we define b-generalized skew derivations of prime rings. Then we describe all possible forms of two b-generalized skew derivations F and G satisfying the condition F(x)x − xG(x) = 0, for all x ∈ S, where S is the set of the evaluations of a multilinear polynomial f(x1, ..., xn) over C with n non-commuting variables. Several potential research topics related to our current work are also presented. © 2021, The Author(s), under exclusive license to Springer Nature Switzerland AG
Corrigendum to “Presence and function of kisspeptin/KISS1R system in swine ovarian follicles” (Theriogenology (2018) 115 (1–8), (S0093691X1830147X), (10.1016/j.theriogenology.2018.04.006))
No full textThe authors regret the following changes to the author group G. Basinia, F. Grassellia, S. Bussolatia, R. Ciccimarraa, M. Maranesib, A. Bufalarib, C. Dall'Agliob, F. Parilloc,#, M. Zeranib,c,*. a Dipartimento di Scienze Mediche Veterinarie, Università di Parma, 43126 Parma, Italy. b Dipartimento di Medicina Veterinaria, Università di Perugia, 06126 Perugia Italy. c Scuola di Bioscienze e Medicina Veterinaria, Università di Camerino, 62024 Matelica Italy. # Deceased. * Corresponding author: tel.: +39 0755857642; fax +39 0755857654. E-mail address: [email protected] (M. Zerani). And to the acknowledgements and figures
Logarithmic variance profiles and the corresponding f-1 spectra of temperature fluctuations in turbulent Rayleigh-Bénard convection
No full textWe report experimental results for the temperature variance 2(z) and the corresponding frequency spectra P(f) in turbulent Rayleigh-Bénard convection (RBC) in a cylindrical sample of aspect ratioT= D/L = 1:00 (D = 1:12 m is the diameter and L = 1:12 m the height). The measurements were conducted in the Rayleigh-number range 1011 < Ra < 1:35 1014 and Pr ' 0:8. For Ra = 1:35x1014, 2(z) could be described well by a logarithmic dependence on the vertical position z in a range of z 1 < z < z 2 with z 1 ' 70 and z 2 = 0:1L. Here L=(2Nu) is the thickness of a thin thermal sublayer adjacent to the horizontal plate where the heat flux (denoted by the Nusselt number Nu) is carried mostly by thermal diffusion. In the log layer, we found that the temperature spectra had a significant frequency range over which P(f) f with close to 1. As Ra decreased, increased so that the log layer became thinner. At Ra = 2:05 1011, z 2 < z 1 and therefore there was no range for a log layer. Correspondingly, the temperature spectrum near the horizontal plate did not have the f1 scaling form either
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