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This paper presents the forming method of head toothing with the application of rolling extrusion technology. Tools numerical models were used in numerical calculations. The presented numerical results concern metals flow kinematics, distributions of stresses and strains. Determined in the process technological parameters of head toothing forming allow foreseeing real material flow in the experiment planned for conducting.

Kuba Ptaszkowski,1 Małgorzata Paprocka-Borowicz,2 Lucyna Słupska,2 Janusz Bartnicki,1,3 Robert Dymarek,4 Joanna Rosińczuk,4 Jerzy Heimrath,5 Janusz Dembowski,6 Romuald Zdrojowy6 1Department of Obstetrics, 2Department of Clinical Biomechanics and Physiotherapy in Motor System Disorders, Wroclaw Medical University, Wroclaw, Poland; 3Department of Obstetrics and Gynecology, Health Center Bitterfeld/Wolfen gGmbH, Bitterfeld-Wolfen, Germany; 4Department of Nervous System Diseases, 5Department of Gynaecology and Obstetrics, Faculty of Health Science, 6Department and Clinic of Urology, Faculty of Postgraduate Medical Training, Wroclaw Medical University, Wroclaw, Poland Objective: Muscles such as adductor magnus (AM), gluteus maximus (GM), rectus abdominis (RA), and abdominal external and internal oblique muscles are considered to play an important role in the treatment of stress urinary incontinence (SUI), and the relationship between contraction of these muscles and pelvic floor muscles (PFM) has been established in previous studies. Synergistic muscle activation intensifies a woman’s ability to contract the PFM. In some cases, even for continent women, it is not possible to fully contract their PFM without involving the synergistic muscles. The primary aim of this study was to assess the surface electromyographic activity of synergistic muscles to PFM (SPFM) during resting and functional PFM activation in postmenopausal women with and without SUI.Materials and methods: This study was a preliminary, prospective, cross-sectional observational study and included volunteers and patients who visited the Department and Clinic of Urology, University Hospital in Wroclaw, Poland. Forty-two patients participated in the study and were screened for eligibility criteria. Thirty participants satisfied the criteria and were categorized into two groups: women with SUI (n=16) and continent women (n=14). The bioelectrical activity of PFM and SPFM (AM, RA, GM) was recorded with a surface electromyographic instrument in a standing position during resting and functional PFM activity.Results: Bioelectrical activity of RA was significantly higher in the incontinent group than in the continent group. These results concern the RA activity during resting and functional PFM activity. The results for other muscles showed no significant difference in bioelectrical activity between groups.Conclusion: In women with SUI, during the isolated activation of PFM, an increased synergistic activity of RA muscle was observed; however, this activity was not observed in asymptomatic women. This may indicate the important accessory contribution of these muscles in the mechanism of continence. Keywords: pelvic floor muscles, postmenopausal period, stress urinary incontinence, surface electromyography, synergistic muscle

This paper presents results of numerical calculations for the rolling process by means of three tools of stepped shafts from aluminum alloy 7075. Forming with the usage of tools with three different wedge spreading angles underwent analysis. In the paper, the obtained distributions of stresses, strains and Cockcroft-Latham damage criterion were given. Moreover, the influence of the wedge spreading angle on shape faults presence in the obtained product was determined. At the same time, the force parameters, which play a crucial role in the designed experiment, were analyzed.

This paper presents results of numerical calculations of T-pipe joints (tee) forming process for a wide scope of industrial applications. FEM analyses were conducted for the chosen process technological parameters and tools designs. The kinematics of metal flow in the area of the formed flanges was analysed. Distributions of stresses, strains and damage criterion during forming were determined. Calculated values of forces and moments acting on tools and workpieces allow for designing of tools geometry for experimental verification of the proposed forming process.

In this paper the numerical analysis of bevel gear forming is presented. Simulations are made by means of FEM using Deform 3D software. Distributions of stress, strain, temperature and Cockroft - Latham damage criterion are presented at various process parameters. Obtained shape of final part and calculated loads during the process course can be useful for the further industrial applications.

The paper presents chosen aspects of the skew rolling process of hollow stepped products with the use of a skew rolling mill designed and manufactured at the Lublin University of Technology. This machine is characterized by the numerical control of spacing between the working rolls and the sequence of the gripper axial movement, which allows for the individual programming of the obtained shapes of parts such as stepped axles and shafts. The length of these zones and the values of possibly realizable cross-section reduction and obtained outlines are the subject of this research paper. The chosen results regarding the influence of the technological parameters used on the course of the process are shown in the present study. Numerical modelling using the finite element method in Simufact Forming, as well as the results of experimental tests performed in a skew rolling mill, were applied in the conducted research. The work takes into account the influence of cross-section reduction of the hollow parts and the feed rate per rotation on the metal flow mechanisms in the skew rolling process. The presented results concern the obtained dimensional deviations and changes in the wall thickness determining the proper choice of technological parameters for hollow parts formed by the skew rolling method. Knowledge about the cause of the occurrence of these limitations is very important for the development of this technology and the choice of the process parameters.

Predictions of the atmospheric dispersion of radionuclides accidentally released from a nuclear power plant are influenced by two large sources of uncertainty: one associated with the meteorological data employed, and one with the source term, i.e. the temporal evolution of the amount and physical and chemical properties of the release. A methodology is presented for quantitative estimation of the variability of the prediction of atmospheric dispersion resulting from both sources of uncertainty. The methodology, which allows for efficient calculation, and thus is well suited for real-time assessment, is applied to a hypothetical accidental release of radionuclides., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This article presents the results of theoretical-experimental testing of the process of rotational compression of hollow stepped shafts. The advantages of the technology and the potential area of its application were discussed. Further on, the limits of the rotational compression technology, preventing the manufacturing of high-quality products, were presented. The research was conducted on the basis of numerical modelling using the finite element method in Simufact Forming, as well as the results of experimental tests performed in a forging machine for rotational compression. On the basis of the results obtained, it can be stated that the process of rotational compression of hollow stepped shafts can be hindered by the following phenomena: uncontrolled slip, deformation of the semi-finished product wall, twisting of the formed steps, material cracking, and deformation of the cross-section of the formed steps. The possibility of those hindrances occurring depends heavily on the assumed technological parameters of the process. For this reason, knowledge of the cause of occurrence of those limitations is vital for the development of the technology and the choice of the process parameters.

The article presents the issue of material fracture during the process of cross-wedge rolling (CWR). The object of the research was the process of forming a harrow tooth preform. In the conducted analysis nine damage criteria were applied. The critical value of damage was determined with a new calibrating test, basing on rotational compression of a sample in a channel. The results of calculations were compared to the results of experimental testing performed in laboratory conditions in Lublin University of Technology. On the basis of the obtained results an assessment of the applied damage criteria and their applicability in the analysis of CWR processes was conducted.

Waste tanks at the nuclear facility located at Sellafield, UK, represent a nuclear source which could release radionuclides to the atmosphere. A model chain which combines atmospheric transport, deposition as well as riverine transport to sea has been developed to predict the riverine activity concentrations of 137 Cs. The source term was estimated to be 9 × 10 4  TBq of 137 Cs, or 1% of the assumed total 137 Cs inventory of the HAL (Highly Active Liquid) storage tanks. Air dispersion modelling predicted 137 Cs deposition reaching 127 kBq m -2 at the Vikedal catchment in Western Norway. Thus, the riverine transport model predicted that the activity concentration of 137 Cs in water at the river outlet could reach 9000 Bq m -3 in the aqueous phase and 1000 Bq kg -1 in solid phase at peak level. The lake and river reaches showed different transport patterns due to the buffering effects caused by dilution and slowing down of water velocity.

Background: Pelvic floor muscle (PFM) training is recommended to increase their strength and endurance. Muscles which act synergistically with PFM are taken into consideration in the therapeutic management of weakened PFM., Research Question: how does electromyography activity of the synergists muscle to PFM change concerning pelvis position and does the greater bioelectric activity of synergist muscles affect PFM function?, Methods: A prospective, observational study evaluating the surface electromyography (sEMG) activity of selected synergist muscles of the PFM depending on the orientation of the pelvis. One hundred thirty-one menopausal women registered for the study were screened for inclusion and exclusion criteria, and by the results, eighty-two participants were enrolled for measurements. The comparisons of results between the values obtained in different positions of the pelvis (anterior pelvic tilt - P1, posterior pelvic tilt - P2 and neutral pelvic tilt - P3) were performed using Kruskal-Wallis test. A multivariate linear regression analysis was used to assess relationships between the bioelectrical activity of PFM and activity of all tested muscles - rectus abdominis (RA), gluteus maximus (GM), and adductor magnus (AM)., Results: Higher RA, GM, AM bioelectrical activity was observed in the P2 as compared to P3 (during resting and functional PFM activity)(p < 0.05). Multivariate linear regression did not find the association between the bioelectrical activity of PFM and the activity of all synergist muscles in each position., Significance: sEMG activity of selected muscles acting synergistically with PFM differ depending on the pelvis position and is the highest in the posterior pelvic tilt. Greater activity of the synergists, resulting from the pelvic position, does not affect the myoelectric activity of PFM. It seems that muscles that act synergistically with PFM may not play such a significant role in the therapeutic management of PFM., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Pregnancy is a special time in the life of a woman, which induces many changes not only in the biological, but also in the biopsychosocial dimension., Objectives: The aim of the study was to evaluate the factors affecting the sense of coherence (SOC) among women during pregnancy. It was hypothesized that a high SOC will depend on a high level of received support, lack of the risk of mental disorders in the perinatal period and physiological course of pregnancy., Material and Methods: Factographic material was collected by a diagnostic survey method. As a 1st research tool, the Polish adaptation of the Sense of Coherence - Orientation to Life Questionnaire (SOC-29) was used. Another research tool was the Edinburgh Postnatal Depression Scale (EPDS), used here for pregnant women and therefore called Edinburgh Depression Scale (EDS)., Results: We analyzed the data of all 200 women with physiological pregnancies and 200 women with complicated pregnancies from whom a complete valid responses were obtained. All women were aged between 18 and 36 years. Significant predictors of low SOC results in the model were: age (odd ratio [OR] = 0.929, 95% confidence interval [CI] 0.870-0.992, p = 0.0280), being multipara (OR = 1.996, 95% CI 1.271-3.135, p = 0.0027), having never/occasionally husband/partner support (OR = 1.978, 95% CI 1.070-3.656, p = 0.0295), and EDS results (OR = 1.312, 95% CI 1.169-1.472, p = 0.0000)., Conclusions: Predisposing factors for the occurrence of a low rate of SOC in pregnant women are: lower age, multiparity, lack of social support, especially from the husband/partner, and the risk of depression during pregnancy. This may result from the fact that a strong SOC develops in the process of socialization, and with age we acquire the ability to accurately assess reality.

Poland is the second most important emission source after Germany in contributing atmospheric nitrogen deposition to the Baltic Sea basin. The main sectors contributing to reactive nitrogen emissions from Polish sources, in the period 1995-2014, are combustion and transportation, responsible together for over 97% of nitrogen oxide emissions, and agriculture responsible for over 98% of ammonia emissions. The EMEP MSC-W model with 50-km resolution was used for estimating the contribution of nitrogen emission sources from Poland to nitrogen deposition into the Baltic Sea basin and its sub-basins, in the period 1995-2014. Polish contribution in this period is mainly visible in annual wet deposition of reduced nitrogen with the range 13-18% and in wet deposition of oxidized nitrogen: 9-15%. Concerning sub-basins, a major contribution for Polish sources to total nitrogen deposition can be noticed for Baltic Proper with the range 13-19%, followed by northern sub-basins (7-18%) and finally by three western sub-basins (5-7%). Polish contribution to the Baltic Sea Basin in the year 2013 was analyzed in more detail using two models, the EMEP MSC-W model with 50-km resolution and model developed at the Institute of Meteorology and Water Management in Warsaw with 14-km resolution (IMWM Model). Both models give similar results concerning the deposition of oxidized nitrogen from Polish sources, but results show that the deposition of reduced nitrogen calculated with IMWM model is lower. The most likely reasons for the differences are different parameterizations of the deposition processes and chemical reactions in both models.

Background: Menopausal women often experience the prolapse of the uterus, bladder and rectum resulting from the failure and weakening of the pelvic floor muscles (PFM). Strengthening of the PFM through the standard exercises is recognized as an effective way of preventive measures and conservative treatment of the symptoms listed above, but still need to be improved., Aim: The goal was the objective assessment of resting and functional bioelectrical activity of PFM in women during menopause and its comparison in three different positions of the pelvis: anterior pelvic tilt - position 1 (P1), posterior pelvic tilt - position 2 (P2), and neutral pelvic tilt - position 3 (P3)., Design: Prospective, cross-sectional observational study., Setting: Department and Clinic of Urology of a University Hospital., Population: The target group of this study included women in the menopausal period (inpatient and outpatient)., Methods: The study evaluating resting and functional activity of the PFM depending on the orientation of pelvis. Bioelectric activity was assessed with an electromyographic instrument (sEMG) and endovaginal electrodes. The inclination angle was measured with an inclinometer. The comparisons of results between the values obtained in P1, P2, and P3 were performed using one-way Analysis of Variance (ANOVA)., Results: One hundred thirty-one registered for the study were screened for inclusion and exclusion criteria and on the basis of the results 82 participants were enrolled for analysis. The highest mean resting activity of sEMG PFM (µV) was observed in P2 and it amounted to 11.6 µV (SD=5.5 µV) in P1 the value equaled 9.8 µV (SD=4.8 µV) and P3-9.0 µV (SD=4.2 µV). The results revealed a significant statistical difference (main effect: P=0.0007). Considering the functional sEMG activity of PFM (µV), the highest mean value was recorded in P2., Conclusions: Posterior pelvic tilt position determines higher resting and functional bioelectric activity of PFM. Additionally, electromyographic activity of PFM increases during the pelvic movement backwards., Clinical Rehabilitation Impact: These positions should be implemented in therapy in order to improve the effectiveness of the effect on the pelvic floor.

The Russian nuclear submarine K-27 suffered a loss of coolant accident in 1968 and with nuclear fuel in both reactors it was scuttled in 1981 in the outer part of Stepovogo Bay located on the eastern coast of Novaya Zemlya. The inventory of spent nuclear fuel on board the submarine is of concern because it represents a potential source of radioactive contamination of the Kara Sea and a criticality accident with potential for long-range atmospheric transport of radioactive particles cannot be ruled out. To address these concerns and to provide a better basis for evaluating possible radiological impacts of potential releases in case a salvage operation is initiated, we assessed the atmospheric transport of radionuclides and deposition in Norway from a hypothetical criticality accident on board the K-27. To achieve this, a long term (33 years) meteorological database has been prepared and used for selection of the worst case meteorological scenarios for each of three selected locations of the potential accident. Next, the dispersion model SNAP was run with the source term for the worst-case accident scenario and selected meteorological scenarios. The results showed predictions to be very sensitive to the estimation of the source term for the worst-case accident and especially to the sizes and densities of released radioactive particles. The results indicated that a large area of Norway could be affected, but that the deposition in Northern Norway would be considerably higher than in other areas of the country. The simulations showed that deposition from the worst-case scenario of a hypothetical K-27 accident would be at least two orders of magnitude lower than the deposition observed in Norway following the Chernobyl accident., (Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.)