External Validity of the Novel Surrogate Measures for Occipitocervical Alignment

Abstract Purpose: Occipitocervical fusion is a rare and often challenging surgical procedure. Several methods have been introduced to obtain the best measures for occipitocervical alignment. The mandible-C2 angle was first introduced in 2020. In this study we aimed to evaluate the out-of-sample validity of this measures. Methods: To compare our results, we followed the same methodology as the root article. We retrospectively studied 274 lateral cervical radiographs of patients aging 1 to 87 years who had no cervical pathology evident on X-ray. A board-certified radiologist and a second-year radiology resident, performed the measurements pertaining to five specific angles as suggested by Bellabarba. The five angles measured consisted of (1) anterior C2 body/anterior mandible angle, (2) anterior C2 body/posterior mandible angle, (3) posterior C2 body/anterior mandible angle, (4) posterior C2 body/posterior mandible angle, and (5) Occiput-C2 Angle. Results: Inter-rater correlation data was calculated for single and average measures. The Inter-rater agreement for individual angle measures of O-C2A, AB/AM, AB/PM, PB/AM, and PB/ PM were 0.49, 0.11, 0.25, 0.33, and 0.49 respectively. The Intraclass correlation coefficient for average measures of O-C2A, AB/AM, AB/PM, PB/AM, and PB/PM were 0.66, 0.20, 0.40, 0.50, and 0.66 respectively. Conclusion: Our study did not show satisfying results to confirm using these angles as a reliable marker for occipitocervical alignment, except for one of them, showing outcomes relatively compatible with our standard angl

In Vitro Fertilized Embryos do not Secrete Detectable HLA-G on Day Two

ABSTRACT Background: Pregnancy is a successful transplantation. The factors evading rejection of the fetus are poorly understood. Recently an interest has grown, in HLA-G molecules as one of these factors. Since these antigens are mainly expressed on the surface of cytotrophoblasts that are in direct contact with maternal tissues, it has been suggested that these molecules may have a role in induction of immune tolerance in mothers. Objective: to find the association of soluble HLA-G (sHLA-G) and the success of pregnancy with intracytoplasmic sperm injection (ICSI) procedure. Methods: In this study, the supernatant of 287 individually cultured embryos corresponding to 96 women under ICSI procedure were assayed for soluble HLA-G1 and G5 by a sandwich ELISA. Results: Clinical pregnancy successfully occurred in 30 of candidates. No differences in clinical parameters (age, infertility duration, stimulation regimen) were observed between pregnant and nonpregnant women under ICSI procedure. None of the embryo supernatants in either group showed any detectable sHLA-G molecules. Conclusion: Our results showed that detectable level of sHLA-G is not produced by day 2 embryos and such a measurement may not provide reliable information for embryo selection and estimation of pregnancy success

Krein Regularization of \lambda\phi^4

We calculate the four-point function in \lambda\phi^4 theory by using Krein regularization and compare our result, which is finite, with the usual result in \lambda\phi^4 theory. The effective coupling constant (\lambda_\mu) is also calculated in this method

Effective Action of λφ3 in Krein Space Quantization

The appearance of divergence creates computational issues in the process of calculating the one-loop effective action of λφ3 in quantum field theory. In this paper, it is demonstrated that using Krein space quantization with Ford’s method of fluctuated metrics, divergence can be removed and that without using any traditional regularization method, it is possible to arrive at a finite solution for the effective action.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author