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We describe the Stiefel–Whitney classes (SWCs) of orthogonal representations 휋 of the finite special linear groups G = SL ⁡ (2 , F q) , in terms of character values of 휋. From this calculation, we can answer interesting questions about SWCs of 휋. For instance, we determine the subalgebra of H * ⁢ (G , Z / 2 ⁢ Z) generated by the SWCs of orthogonal 휋, and we also determine which 휋 have non-trivial mod 2 Euler class. [ABSTRACT FROM AUTHOR]

Certain convergence estimates for the semi-exponential operators associated with 1 + x² are established including weighted approximation, a direct result involving classical modulus of continuity and quantitative Voronovskaya-type theorem in weighted spaces. Initially, the moments are obtained following a recurrence relation for these operators and then some direct results are estimated. [ABSTRACT FROM AUTHOR]

Byline: Tarang. Goyal, Anupam. Varshney, Neha. Malik A young woman presented with vulval and facial papules for 5 years. On examination, symmetrical lichenified plaques with confluent and discret skin-colored papules [...]

In the present paper, we propose a sequence of generalized genuine Baskakov–Durrmeyer-type link operators. In terms of ordinary approximation, we estimate local and global direct results and also study the weighted approximation result. In terms of simultaneous approximation, we establish an asymptotic formula of Voronovskaja kind. In the last section, we prove convergence in L p {L_{p}} -norm. [ABSTRACT FROM AUTHOR]

Motivated by a number of recent investigations, we consider a new analogue of Bernstein-Durrmeyer operators based on certain variants. We derive some approximation properties of these operators. We also compute local approximation and Voronovskaja type asymptotic formula. We illustrate the convergence of aforementioned operators by making use of the software MATLAB which we stated in the paper. [ABSTRACT FROM AUTHOR]

In the present paper, we consider ( p, q )-analogue of the Baskakov–Beta operators and using it, we estimate some direct results on approximation. Also, we represent the convergence of these operators graphically using MATLAB. [ABSTRACT FROM AUTHOR]

Several modifications of the discrete operators are available in the literature. In the recent years, certain modifications of the well-known Baskakov and Szasz--Mirakyan operators have been discussed based on certain parameters. We propose mixed summation-integral type operators and estimate the quantitative asymptotic formula and a global direct result for the special case. For general case, we establish moments and some direct convergence results in ordinary approximation, which includes pointwise approximation, asymptotic formula and a direct result in terms of modulus of continuity. [ABSTRACT FROM AUTHOR]

Young people living with HIV in the US have the potential to live long and healthy lives. However, the psychosocial impact of an HIV diagnosis, complicated by poverty, inequality, stigma and marginalization, create structural and behavioral challenges for young people that can overwhelm them and their health care providers. This narrative provides a reflective analysis of insights and discussions captured through participant observation at a five-day conference for young people living with HIV. The manuscript provides practitioners with an additional interpretive lens, highlighting participant observation as a valuable methodology to better understand and design programs for young people living with HIV. The article calls for youth-led, peer-based approaches that focus on support for disclosure of HIV status, self-esteem in relationships and adherence to medication. [ABSTRACT FROM AUTHOR]

Hodgkin lymphoma (HL) demonstrates heterogenous histologic findings, clinical presentation, and outcomes. Using the United States Surveillance, Epidemiology, and End Results (SEER) data we examined relationships between patient characteristics, clinical features at diagnosis, and survival in HL patients. From 2000 to 2007, 16,710 cases were recorded in 17 SEER registries. Blacks and Asians had low incidence (black/white incidence rate ratio (IRR) 0.86, P < .01; Asian/white IRR 0.43, P < .01). The bimodal pattern of incidence was less prominent for black males. Asians and Blacks presented at a mean age of 38 years compared to 42 years for Whites (P < .001). Race was a predictor for survival with HR of 1.19 (95% CI 1.11-1.28) for Blacks. Age was the most important predictor of survival (HR for patients ≥45 years 5.08, 95% CI 4.86-5.31). These current patterns for presentation and outcomes of HL help to delineate key populations in order to explore risk factors for HL and strategies to improve treatment outcomes. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The sigma-1 and sigma-2 receptors have been shown to play important roles in CNS diseases, cancer, and other disorders. These findings suggest that targeting these proteins with small-molecule modulators may be of important therapeutic value. Here we report the development of a new class of tetrahydroindazoles that are highly potent and selective ligands for sigma-1. Molecular modeling was used to rationalize the observed structure-activity relationships and identify key interactions responsible for increased potency of the optimized compounds. Assays for solubility and microsomal stability showed this series possesses favorable characteristics and is amenable to further therapeutic development. The compounds described herein will be useful in the development of new chemical probes for sigma-1 and to aid in future work therapeutically targeting this protein. [ABSTRACT FROM AUTHOR]

Background: Flexible endoscopic cricopharyngeal myotomy and septotomy offer a minimally invasive transluminal option for the treatment of symptomatic Zenker's diverticulum (ZD). There is currently no consensus regarding postoperative follow-up imaging. We suggest a standardized computed tomography (CT) esophagram protocol for radiographic evaluation of postoperative findings., Methods: Single center retrospective analysis of patients with symptomatic ZD who underwent flexible endoscopic diverticulotomy and postoperative imaging with CT esophagram from January 2015 to March 2020. An experienced radiologist blinded to the initial imaging reports prospectively interpreted all CT esophagram findings, in order to minimize bias., Results: Twenty-one patients underwent CT esophagram following flexible endoscopic diverticulotomy for ZD. Diverticulotomy was technically successful in all patients. Most common findings on imaging included: atelectasis (13/21; 62%), persistent esophageal diverticulum (7/21; 33%), pneumomediastinum (3/21; 14%), aspiration (2/21; 10%), and extraluminal air and contrast extravasation consistent with focal esophageal perforation (1/21; 5%)., Conclusions: We describe a standardized, simple, and accessible CT esophagram protocol for postoperative imaging of patients with post-flexible endoscopic cricopharyngeal myotomy and septotomy for ZD. CT esophagram facilitates a definitive exclusion of focal esophageal perforation as a postoperative complication of flexible endoscopic diverticulotomy by ruling out extraluminal air and contrast extravasation., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tgh.amegroups.com/article/view/10.21037/tgh-20-269/coif). DY reports that he is a consultant for Boston Scientific, Lumendi, and Steris, outside the submitted work; PVD reports that he is a consultant for Boston Scientific, Olympus, Cook Medical, Lumendi, and Microtech, outside the submitted work. The other authors have no conflicts of interest to declare., (2022 Translational Gastroenterology and Hepatology. All rights reserved.)

Chemokines such as stromal derived factor 1 and their G protein coupled receptors are well-known regulators of the development and functions of numerous tissues. C-X-C motif chemokine ligand 12 (CXCL12) has two receptors: C-X-C chemokine motif receptor 4 (CXCR4) and atypical chemokine receptor 3 (ACKR3). ACKR3 has been described as an atypical "biased" receptor because it does not appear to signal through G proteins and, instead, signals solely through the β -arrestin pathway. In support of this conclusion, we have shown that ACKR3 is unable to signal through any of the known mammalian G α isoforms and have generated a comprehensive map of the G α activation by CXCL12/CXCR4. We also synthesized a series of small molecule ligands which acted as selective agonists for ACKR3 as assessed by their ability to recruit β -arrestin to the receptor. Using select point mutations, we studied the molecular characteristics that determine the ability of small molecules to activate ACKR3 receptors, revealing a key role for the deeper binding pocket composed of residues in the transmembrane domains of ACKR3. The development of more selective ACKR3 ligands should allow us to better appreciate the unique roles of ACKR3 in the CXCL12/CXCR4/ACKR3-signaling axis and better understand the structural determinants for ACKR3 activation. SIGNIFICANCE STATEMENT: We are interested in the signaling produced by the G protein coupled receptor atypical chemokine receptor 3 (ACKR3), which signals atypically. In this study, novel selective ligands for ACKR3 were discovered and the site of interactions between these small molecules and ACKR3 was defined. This work will help to better understand the unique signaling roles of ACKR3., Competing Interests: The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2022 by The Author(s).)

Stressed soybeans produce a group of phytoalexins that belong to the 6a-hydroxypterocarpan family of flavonoids. Certain of the more prominent members, such as the glyceollins I, II, and III, have demonstrated potential antidiabetic properties and promising cytotoxicity in both human breast and prostate cancer cell cultures with preliminary studies in animals further demonstrating antitumor effects in estrogen-dependent, human breast cancer cell implants. Although syntheses of glyceollin I have been reported previously, this work constitutes the first total directed synthesis of (±)-glyceollin II. It involves 12 steps with an overall yield of 7% using practical methods that should be readily scalable to produce quantities needed for advanced biological characterization. Highlights include a novel intramolecular benzoin condensation, a chelation-controlled lithium aluminum hydride-mediated reduction, and an intramolecular cyclization via the formation of a transient epoxide intermediate to cap the construction of the 6a-hydroxypterocarpan system. Additionally, a dihydro analogue has been obtained, and several isolated intermediates have been made available for evaluation of their biological properties and possible contributions toward elaborating key structure-activity relationship data among this family of promising phytoalexins elicited from stressed soybeans.