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The paper presents a non-local line method used to the fatigue life calculation of notched elements. The presented method is based on the concept of an effective length which determines the size of the equivalent fatigue zone. Effective values of normal stress calculated in the critical plane with a weight function were applied when determining the equivalent fatigue zone. Simulation studies were performed for two types of steel and two types of loading. Five different series of tests and simulations were used. Experimental studies were carried out for 40 HM-T and EA4T steels. These materials are used in railway industry, including the manufacturing of coupling bars. The notched test specimens contained notches with a tip radius of 0.2, 0.5, 0.8 and 1 mm. Stress calculations were performed using the finite element method by adopting cyclic material properties described by the model of a multi-linear hardening. Non-local calculations were performed in a defined critical plane for normal stress distribution and a weight function. As a result, the function of variation of the effective length depending on the loading level and geometry of the notch has been determined. [ABSTRACT FROM AUTHOR]

The work presents verification of Neuber's fictitious radius method, used in fatigue life calculation of notched elements and welded joints. Stress values, calculated according with fictitious radius method, were compared with smooth specimens Basquin fatigue curves, and number of cycles was read. However, obtained calculated number of cycles of fatigue life does not correspond to experimental fatigue life, especially in a low cycle fatigue range. Hence, different equivalent microstructural length values were calculated for different loading levels. It was observed that equivalent microstructural length depends on loading level and type of loading. Finally, equivalent microstructural length was presented in a linear regression equation, as dependant on loading level and its relation to yield strength. [ABSTRACT FROM AUTHOR]

In the paper, the concept of non-local line method is presented and used for determining the effective length for notched elements. Experimental tests and calculations were performed for 40 HM-T (42CrMo4+QT) steel made specimens of two types, i.e. smooth specimens, and notched specimens with notch radius equal to 0.2 mm, 0.5 mm, 0.8 mm, and 1 mm. The performed FEM calculations took into account the multi-linear hardening model and cyclic material properties. The concept of the presented non-local line method bases on finding the position of critical plane and determining the effective length, meant as the fracture process zone. During numerical stress gradient simulations, also the weight function was implemented. It was observed that the effective length increases as the load increases.

Obesity is a chronic disease caused primarily by the imbalance between the amount of calories supplied to the body and energy expenditure. Not only does it deteriorate the quality of life, but most importantly it increases the risk of cardiovascular diseases and the development of type 2 diabetes mellitus, leading to reduced life expectancy. In this review, we would like to present the molecular pathomechanisms underlying obesity, which constitute the target points for the action of anti-obesity medications. These include the central nervous system, brain-gut-microbiome axis, gastrointestinal motility, and energy expenditure. A significant part of this article is dedicated to incretin-based drugs such as GLP-1 receptor agonists (e.g., liraglutide and semaglutide), as well as the brand new dual GLP-1 and GIP receptor agonist tirzepatide, all of which have become "block-buster" drugs due to their effectiveness in reducing body weight and beneficial effects on the patient's metabolic profile. Finally, this review article highlights newly designed molecules with the potential for future obesity management that are the subject of ongoing clinical trials.

Purpose: Flexible bronchoscopy (FB) causes airway narrowing and may cause respiratory failure (RF). Noninvasive mechanical ventilation (NIV) is used to treat RF. Until recently, little was known about noninvasive mechanical ventilation assisted flexible bronchoscopy (NIV-FB) risk and complications., Materials and Methods: A retrospective analysis of NIV-FB performed in 20 consecutive months (July 1, 2018-February 29, 2020) was performed. Indications for: FB and NIV, as well as impact of comorbidities, blood gas results, pulmonary function test results and sedation depth, were analyzed to reveal NIV-FB risk. Out of a total of 713 FBs, NIV-FB was performed in 50 patients with multiple comorbidities, acute or chronic RF, substantial tracheal narrowing, or after previously unsuccessful FB attempt., Results: In three cases, reversible complications were observed. Additionally, due to the severity of underlining disease, two patients were transferred to the ICU where they passed away after >48h. In a single variable analysis, PaO 2 69 ​± ​18.5 and 49 ​± ​9.0 [mmHg] (p ​< ​0.05) and white blood count (WBC) 10.0 ​± ​4.81 and 14.4 ​± ​3.10 (p ​< ​0.05) were found predictive for complications. Left heart disease indicated unfavorable NIV-FB outcome (p ​= ​0.046)., Conclusions: NIV-FB is safe in severely ill patients, however procedure-related risk should be further defined and verified in prospective studies., Competing Interests: Declaration of competing interest The authors declare no conflict of interests., (Copyright © 2021 Medical University of Bialystok. Published by Elsevier B.V. All rights reserved.)

Recently, it has been shown in the murine model that platelet maturation takes place, to some extent, in the lungs. The extrapolation of these findings to humans leads to the possibility that chronic lung diseases could affect platelet maturation and, consequently, the platelet count. The aim of this study was to investigate whether there are changes in the platelet count in patients with chronic obstructive disease (COPD). The study included 44 patients, aged 66.5 ± 5.5 years, in stage II-IV COPD. The control group consisted of 48 age- and gender-matched patients without any respiratory diseases. We failed to find a significant difference in the platelet count between the two groups: 231 ± 80 vs. 223 ± 63 x 10 3 /μL, respectively (p = 0.61). However, the number of platelets in the COPD patients was inversely associated with hemoglobin content (r = -0.57; p < 0.001), hematocrit (r = -0.40; p = 0.006), and the red cell count (r = -0.51; p < 0.001); the blood morphology indices that are typically increased in severe COPD. Such associations were absent in the control non-COPD group. We conclude that COPD has no influence on the platelet count in humans.