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Abstract

The primary objective of the case study is to improve monitoring, controlling, planning and managing the extraction processes in surface lignite mining. Under the North Bohemian Lignite Basin (also Most Basin) conditions and the Sokolov Basin, wheeled excavators are deployed as the main technology for extracting coal and overlying rock. Their real-time spatial position can be tracked based on data from GNSS technology, inclinometers, and incremental rotary encoders. The measured data is sent to a remote server and stored in the database. It also serves to calculate volumes of extracted masses. Volume calculation, space position visualisation, and wheel boom movements are performed in KVASoftware. It is a program designed for modelling and designing quarries. Knowing the position of the wheel against the digital terrain (quarry), the model is essential for the implementation of many risk-elimination applications, namely with respect to the geological conditions, occupational safety, observance of the profile grade line, the area of extraction, qualitative parameters of the raw material, etc. The mathematical model of backfilling extracted materials is also an integral part of the above-mentioned system.
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Bibliography

[1] J. Benndorf, Mike W.N. Buxton, Sensor-based real-time resource model reconciliation for improved mine production control – a conceptual framework. Mining Technology 125, 1, 54-64 (2016). DOI: https://doi.org/10.1080/14749009.2015.1107342
[2] GeoTel s.r.o., KVA Software, Z jišťování polohy kolesa rýpadla K 800/103/N1 pomocí GP S [GP S – A ided D etermination of the Position of the Bucket Wheel of the K800 Excavator"
[3] Team of authors, Hornická ročenka 2017 [Mining yearbook 2017]: Ostrava, Montanex. ISBN 978-80-7225-454-5, (2018), (in Czech).
[4] D. Sladková, R. Kapica, M. Vrubel, M. Michalusová, Výpočty objemů odtěžených hmot v reálném čase [Calculations of volumes of excavated masses in real-time]. Z pravodaj hnědé uhlí. Most: V ýzkumný ústav pro hnědé uhlí a.s. 2, 10-15 (2012), ISSN 1213-1660, (in Czech).
[5] D. Vrublová, R. Kapica, B . Gibesová, J. Mudruňka, A . Struś, Application of GNSS technology in surface mining. Geodesy and Cartography 42, 4, 122-128 (2016). ISSN: 20296991, DOI: https://doi.org/10.3846/20296991.2016.1268433
[6] D. Vrublová, R. Kapica, M. Vrubel, E . Jiránková, Přesnost určování prostorové polohy kolesa rýpadel [Accuracy of the spatial position determination of excavator wheels]. Z pravodaj hnědé uhlí. Most: V ýzkumný ústav pro hnědé uhlí a. s. 3, 10-15 (2015), ISSN 1213-1660, (in Czech).
[7] J. Benndorf, Making Use of Online Production Data: Sequential Updating of Mineral Resource Models. Mathematical Geosciences 47 (5), 547-563 (2015). DOI: https://doi.org/10.1007/s11004-014-9561-y
[8] M. Vrubel, D. Sládková, M. Talácko, New possibilities of GPS technology in mine surveying. In Proceedings of the 13th International Congress of ISM, Budapest, ISBN 978-963-9038-18-9 (2007).
[9] D. Vrublová, M. Vrubel, I. Maňas, L. Nábělková, Surveying system for bucket wheel excavators and spreaders tracking as a contribution to automation of mining process at Severočeské doly a.s.. In the Proceedings of the International Conference of Geodesy and Mining Surveying 2018: XXV. SDMG conference, 24-26. October 2018, Pilsen. VSB – Technical University of Ostrava, (2018), (in Czech).
[10] J.W. Van Der Merwe, D.C. Andersen, Applications and benefits of 3D laser scanning for the mining industry. Journal of the Southern African Institute of Mining and Metallurgy 113 (3), 213-219 (2013). ISSN: 2225 6253.
[11] Nebojša B. Gnjatović, Srđan M. Bošnjak, Ivan Lj. Milenović, Aleksandar Z. Stefanović, Bucket wheel excavators: Dynamic response as a criterion for validation of the total number of buckets. Engineering Structures 225, 111313 (2020). ISSN 0141-0296, DOI: https://doi.org/10.1016/j.engstruct.2020.111313
[12] D. Sladková, R. Kapica, M. Vrubel, Global navigation satellite system (GNSS) technology for automation of surface mining. International Journal of Mining Reclamation and Environment 25 (3), 284-294, ISSN: 17480930, (2011). DOI: https://doi.org/10.1080/17480930.2011.608879
[13] I. Maňas, Princip generování ploch a výpočtů objemů v Báňském modelu [The principle of generating surfaces and calculating volumes in the Mining Model]. Technická zpráva k programu [Technical report to the program], (2010). (in Czech).
[14] L. Horák, Návrh klasifikace tektonických zlomů z pohledu jejich rizikovosti pro postupy kolesových velkorýpadel [Draft classification of tectonic faults in view of their risk level for the process of large bucket wheel excavators], posudek [assessment]. GeoTec, (2009). (in Czech).
[15] R. Kapica, D. Vrublová, M. Vrubel, The system of tracking the position of the bucket excavator’s wheel for prevention of risk situations. Acta Geodyn. Geomater. 15, 3 (191), 277-287, (2018). DOI: https://doi.org/10.13168/ AGG.2018.0020
[16] E. Jiránková, Utilisation of surface subsidence measurements in assessing failures of rigid strata overlying extracted coal seams. Int. J. Rock Mech. Min. Sci. 53, 111-119, (2012). DOI: https://doi.org/10.1016/j.ijrmms.2012.05.007
[17] L. Al-Shrouf, N. Szczepanski, D. Söffker, Online feature-based multisensor object detection system for bucket-wheel excavators. Int J Adv Manuf Technol 82, 1213-1226 (2016). DOI: https://doi.org/10.1007/s00170-015-7375-9
[18] J. Polák, K. Bailotti, J. Pavliska, L. Hrabovský, Dopravní a manipulační zařízení II [Transport and handling equipment]. Ostrava, VSB-Technical university of Ostrava, (2003). ISBN 80-248-0493-X. (in Czech).
[19] Y. Yuan, Y., Lv, L., Wang, S. et al., Multidisciplinary co-design optimization of structural and control parameters for bucket wheel reclaimer. Front. Mech. Eng. 15, 406-416 (2020). DOI: https://doi.org/10.1007/s11465-019-0578-2
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Authors and Affiliations

Dana Vrublová
1
ORCID: ORCID
Roman Kapica
2
ORCID: ORCID
Stanislav Smelik
3
ORCID: ORCID
Markéta Smeliková
3
ORCID: ORCID

  1. VŠB – Technical University of Ostrava , Faculty of Mining and Geology, Institute of Combined Studies in Most, Dělnická 21, Most, Czech Republic
  2. VŠB – Technical University of Ostrava, Faculty of Mining and Geology, Department of Geodesy and Mine Surveying, 17. listopadu 15, Ostrava – Poruba, 708 00, Czech Republic
  3. Geodetic Office, Baška 111, 739 01 Baška, Czech Republic
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Abstract

The shortage of investment areas may be at least partially satisfied by the development of reclaimed post-mining areas. These are often subsidence zones levelled with hard coal mine waste or reclaimed sub-level old dumps of this waste. From the geotechnical point of view, such grounds represent anthropogenic grounds containing mine waste, and they are considered as possessing unfavourable properties in terms of the foundation of building structures. The paper initially presents the analysis of the properties of waste from the hard coal mining industry, emphasising that they expose several beneficial properties enabling their safe use. The second part of the article is devoted to the determination of soil density using the DPSH probe. It has been found that the applicable standards lack complex relationships that would allow for a reliable interpretation of the measurement results in a wide range of soil types. The last part presents exemplary results of measurements made with the DPSH probe at a construction site. The obtained results allowed for the formulation of several conclusions regarding the possibility of building on a ground made of hard coal waste and the use of dynamic sounding to assess the geotechnical properties of such anthropogenic soil.
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Authors and Affiliations

Rafał Jendruś
1
ORCID: ORCID
Grzegorz Pach
1
ORCID: ORCID
Grzegorz Strozik
1
ORCID: ORCID

  1. Silesian University of Technology, Department of Mining, Safety Engineering and Industrial Automation, 44-100 Gliwice, Poland
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Abstract

The paper presents the results of assessment studies of the time course for technical wear in masonry buildings located in the area of mining-induced ground deformations. By using fuzzy inference system (FIS) and the “if-then” rule, corresponding language labels describing actual damage recorded in structure components were translated into scalar outputs describing the degree of damage to the building. Adopting this approach made it possible to separate damage resulting from additional effects coming from mining-induced ground deformations and the natural wear and tear of masonry structure. By using statistical analysis an exponential function for the condition of building damage and the function of natural wear and tear were developed. Both phenomena were subject to studies as a function of time regarding the technical age of building structure. The results obtained were used to develop a model for the course of technical wear of traditionally constructed buildings used within mining areas.

In the course of natural wear and tear buildings located in mining areas are additionally exposed to forced ground deformations. The increase of internal forces in structure components induced by those effects results in creating an additional stress factor and damage. The hairline cracks and cracks of building structure components take place when the intensity value of mining effects becomes higher than the component stress resistance and repeated effects result in the decrease of structure rigidity. The observations of building behaviour in mining areas show that the intensity of mining activity and the multiplicity of its effect play a substantial role in the course of technical wear of buildings. The studies show that the level of damage resulting from mining effects adds up to natural wear and tear of the building and impairs the global technical condition as compared to similar buildings used outside mining areas.

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Authors and Affiliations

Izabela Dorota Bryt-Nitarska
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Abstract

The objectives of the study were to recognize the main motives for engagement in actions beyond basic professional duties among various professional groups and to identify selected properties of the subject and context of activities that contribute to such beyond-duties engagement. A set of questionnaires in electronic or paper form was completed by 209 employees, including 104 representatives of assistance professions and 95 representatives of creative professions, aged between 21 and 67 years (M = 37.54, SD = 9.55). It was established that the main motives for beyondduties engagement in both groups of professionals under study were self-actualization and acting for the benefit of others. With the use of structural equation modelling, subjective and contextual determinants of engagement in actions beyond basic professional duties were identified as self-efficacy and action meaningfulness. The research discusses the phenomenon of engagement in extra activities at work from the perspective of the acting person/employee. The study results can be useful for managers in setting goals of appropriate type and manner to their employees as well as for task assignment.
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Authors and Affiliations

Agnieszka Bożek
1

  1. Jagiellonian University
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Abstract

The present article attempts to discuss whether a medical conference poster intended for a specific English-speaking discourse community shares the properties of discourse colony (Hoey 1986). The author analyses 12 e-posters, which were displayed during an international neurological conference, presenting findings on epilepsy treatment. First, the author characterises the conference poster, which is followed by a description of discourse community and discourse colony. Next, the analysis of the e-posters is carried out and the results of the analysis are presented. On the basis of these results it might be said that the medical conference poster could be considered a discourse colony as it shares some of its properties.

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Authors and Affiliations

Jacek Pradela
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Abstract

The height of the fundamental frequency (F0) is frequently cited as the major acoustic feature that distinguishes the female voice from the male voice. Women tend to have a signifi cantly higher mean F0 than men. Some studies have indicated that the variability of the fundamental frequency also differs between the two genders and women’s voices may involve higher prosodic explicitness than men’s voices. This study investigates the way in which these features are utilised in rendering the voice of male and female characters in the reading aloud of fiction. To achieve this aim, a representative sample of dialogues selected from audiobooks was analysed acoustically. The results reveal that the reader’s F0 tends to slightly increase in fragments with female characters, but other predictions have not been confirmed. There is no decrease of F0 in dialogues with male characters and, in general, the reader’s variability of F0 seems not to be influenced by the character’s gender.

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Authors and Affiliations

Łukasz Stolarski
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Abstract

Objective: Self-report questionnaire is informative to assess general hearing disability. The aims of this study were to investigate the reliability of Turkish version of spatial hearing questionnaire (SHQ) and to analyze the validity of the SHQ by the correlation with speech, spatial, and qualities of hearing questionnaire (SSQ) and Turkish matrix sentence test (TMST).
Methods: The first part of the study was the psychometric properties of the SHQ with 192 participants (137 with normal hearing, 55 with hearing loss). In the second and main part of the study, we applied two questionnaires (SHQ and SSQ) and TMST to people other than those included in the first part ofthe study (88 participants with bilateral sensorineural hearing loss). We compared the results of these two questionnaires and the TMST with the speech discrimination (SD) scores.
Results: Turkish spatial hearing questionnaire’s internal consistency was 0.94 and 0.97 for individuals with normal hearing and for individuals with hearing loss, respectively. Moderate, positive, statistically significant correlation was observed between the SHQ and SSQ (r = 0:606, p = 0:001 in individuals with hearing loss who do not wear any hearing aid, and r = 0:627, p = 0:001 in hearing aid users), and SHQ and SD (r = 0:561, p = 0:032 in hearing aid users). According to TMST, moderate, positive, statistically significant correlation was found between SSQ and adaptive TMST in individuals with hearing loss who do not wear any hearing aid (r = 0:330, p = 0:033 for S0N90 and r = 0:364, p = 0:018 for S0N270).
Conclusions: Turkish SHQ is a valid and reliable questionnaire for assessing hearing functions. SHQ, SSQ, and TMST are clinically beneficial measuring tools in planning the process of hearing rehabilitation and follow-up.

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Authors and Affiliations

Bünyamin Çildir
1
Suna Tokgöz-Yilmaz
2
Gonca Sennaroğlu
3

  1. Ankara Yıdırım Beyazıt University, Health Sciences Faculty, Speech Language Therapy Department, Ankara, Turkey
  2. Ankara University, Health Sciences Faculty, Audiology Department, Ankara, Turkey
  3. Hacettepe University, Health Sciences Faculty, Audiology Department, Ankara, Turkey
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Abstract

The presented review discusses recent research on human echolocation by blind and sighted subjects, aiming to classify and evaluate the methodologies most commonly used when testing active echolocation methods. Most of the reviewed studies compared small groups of both blind and sighted volunteers, although one in four studies used sighted testers only. The most common trial procedure was for volunteers to detect or localize static obstacles, e.g., discs, boards, or walls at distances ranging from a few centimeters to several meters. Other tasks also included comparing or categorizing objects. Few studies utilized walking in real or virtual environments. Most trials were conducted in natural acoustic conditions, as subjects are marginally less likely to correctly echolocate in anechoic or acoustically dampened rooms. Aside from live echolocation tests, other methodologies included the use of binaural recordings, artificial echoes or rendered virtual audio. The sounds most frequently used in the tests were natural sounds such as the palatal mouth click and finger snapping. Several studies have focused on the use of artificially generated sounds, such as noise or synthetic clicks. A promising conclusion from all the reviewed studies is that both blind and sighted persons can efficiently learn echolocation.
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Authors and Affiliations

Michał Bujacz
1
Bartłomiej Sztyler
1
Natalia Wileńska
1
Karolina Czajkowska
1
Paweł Strumiłło
1

  1. Institute of Electronics, Lodz University of Technology, Łódz, Poland
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Abstract

The radiation of sound waves from partially lined duct is treated by using the mode-matching method in conjunction with the Wiener-Hopf technique. The solution is obtained by modification of the Wiener-Hopf technique and involves an infinite series of unknowns which are determined from an infinite system of linear algebraic equations. Numerical solution of this system is obtained for various values of the problem parameters, whereby the effects of these parameters on the sound diffraction are studied. A perfect agreement is observed when the results of radiated field are compared numerically with a similar work existing in the literature.

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Authors and Affiliations

Burhan Tiryakioglu
Ahmet Demir
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Abstract

This paper deals with the finite element analysis of the demagnetization process of the line start permanent magnet synchronous motor. Special attention has been paid to demagnetization risk assessment after resynchronization during a short-term supply power outage. The current and torque waveforms have been determined assuming the difference depending initial rotor position angle. It has been demonstrated that the highest demagnetization risk occurs when resynchronization (motor reclosing) is performed whe induced electromotive forces are in anti-phase to the supply voltage waveforms. The effect of cage winding resistance on the risk of demagnetization is examined and discussed.

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Authors and Affiliations

Tomasz Zawilak
ORCID: ORCID
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Abstract

The cartography and quantification of irrigated fields in the context of decreasing rainfall constitute a key element for water resources management. Therefore, in this context, the use of remote sensing methods applied to Landsat-type images with a high spatial resolution for monitoring the changes in land use in general and irrigated crops, in particular, is highly relevant. This paper aims to present a method for mapping spatial and temporal changes in irrigated parcels in the Guigou Plain, located in the central Middle Atlas, based on Landsat images and fieldwork. For the years 1985, 1998, 2010 and 2018, the use of a supervised classification method based on the principle of machine learning, fed by precise field surveys, has made it possible to highlight a significant extension of irrigated areas to the expense of pastureland and rainfed crops. Over the entire period under consideration, the results obtained with good precision (98.5% overall accuracy) showed that the area under irrigated crops has increased from approximately 699 ha to 3988 ha, i.e. an increase of 570%. The corollary of this increase is strong pressure on the water resource, especially groundwater. This information on the total extension of irrigated plots can be taken as a reference in the perspective of reasoned management of water resources in the sector.
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Authors and Affiliations

Abdelaziz El-Bouhali
1 2 3
ORCID: ORCID
Adeline Cotonnec
2
ORCID: ORCID
Sébastien Lebaut
1
ORCID: ORCID
Mhamed Amyay
3
Alban Thomas
2
ORCID: ORCID
Khadija El Ouazani Ech-Chahdi
3
Mohamed Laouanne
3
Emmanuel Gille
1

  1. University of Lorraine, Research Unit “LOTERR”, F-57000 Metz, France
  2. Rennes 2 University, LETG-Rennes UMR 6554 CNRS, Rennes, France
  3. Sidi Mohamed Ben Abdellah University, Fez, Morocco
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Abstract

Permanent grasslands are the most environment-friendly way of using agricultural lands. Apart from producing fodder, grasslands play many other important non-productive functions. Biodiversity is the key factor decisive for their high natural and productive values. Grasslands play an important role in water retention. Not all types of grasslands may be used agriculturally. Out of 16 types of habitats, 10 may be used for production, the others are biologically valuable. The surface area of permanent grasslands in Poland has markedly decreased during the last decade. Now, they constitute slightly more than 20% of agricultural lands occupying 3127.8 thous. ha (in 2019) including 2764 thous. ha of meadows and 363.8 thous. ha of pastures.
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Authors and Affiliations

Mirosław Gabryszuk
1
ORCID: ORCID
Jerzy Barszczewski
1
ORCID: ORCID
Barbara Wróbel
1
ORCID: ORCID

  1. Institute of Technology and Life Sciences – National Research Institute, Falenty, Hrabska Av. 3, 05-090 Raszyn, Poland
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Abstract

The effect of additions of silver or titanium (0.5 or 3 vol.%) microparticles on the microstructure, as well as some physical properties of Al2O3-based composites, were studied. The processing method for the manufacturing of alumina-based composites was a combination of RBAO and SPS processes. After the SPS process, bodies with almost full density were obtained. Observations by optical microscopy show a very fine and homogenous microstructure in all samples. Concerning mechanical properties, the addition of metals on alumina increases its fracture toughness significantly (112% for the sample with additions of silver, while the composite with additions of titanium fracture toughness increases by 72%). In terms of optical properties, both silver and titanium improve the absorbance in the visible range.
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Authors and Affiliations

Enrique Rocha-Rangel
1
ORCID: ORCID
Carlos A. Calles-Arriaga
1
ORCID: ORCID
Juan López-Hernández
1
ORCID: ORCID
José A. Rodríguez-García
1
ORCID: ORCID

  1. Universidad Politécnica de Victoria, Ciudad Victoria, México
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Abstract

The aim of this study was to determine the time-dependent effectiveness of photo-stimulation against bovine sperm cells using a multi-wavelength LED (Light Emitting Diode). Spermatological parameters were evaluated for viability, acrosome structure and motility. In addition, the effect of photo-stimulation on frozen-thawed sperm cells subjected to in vitro capacitation was evaluated in terms of changes in mitochondrial membrane potential. The study consisted of two separate experiments and a total of 32 sperm samples obtained from separate bulls were used. All sperm samples were obtained from Holstein bulls using an artificial vagina. Semen was diluted to a final concentration of 92 x 106 spermatozoa per ml in 0.25 ml straws. The sperm cells were frozen using the conventional method. Straws were kept in a 37°C water bath for 20 seconds and diluted 1:4 in phosphate buffered saline (PBS) to eliminate the potentially deleterious effect of glycerol, the main permeable cryoprotectant in the freezing medium for bull sperm. This dilution also helped in the evaluation of sperm quality parameters. In the first experiment, whereas the 15-10-15 showed no differences with the control, other treatments such as 10-10-10, 5-5-5, and 3-1-3 exhibited significantly higher percentages of viable spermatozoa at 24h. The results obtained for acrosome integrity were pretty much similar to those observed in the sperm viability assessment. In effect, while the treatment consisting of 15-10-15 had no positive effects, shorter treatments exerted a much more positive effect. The percentages of acrosome-intact spermatozoa in 2-1-2 and 1-1-1 were significantly higher than those obtained in the control. The significant differences in mitochondrial membrane potential were observed at 0, 2, 4 and 24h post-photo-stimulation in all treatments, except 15-10-15. The highest increase in the percentage of spermatozoa exhibiting high mitochondrial membrane potential was found in 10-10-10, 5-5-5 and 3-1-3 treatments. With regard to total and progressive motility, whereas 10-10-10 was the best regime, 5-5-5 and 3-1-3 treatments also had a positive effect. However, 15-10-15 appeared to have a stimulating effect upon progressive motility at 2h and 4h but later declined and showed no significant differences with regard to the control at 24h. In the second experiment, not immediately after thawing but after having been kept at room temperature for up to 24h, it was observed that there was no statistical difference in terms of viability, acrosome integrity and total/progressive motility between photostimulation and the control group. This indicates that photo- stimulation is less able to exert a beneficial effect when post-thawed sperm are not immediately stimulated. As a result it was determined that photo-stimulation at a pattern of 10-10-10, 5-5-5, 3-1-3 and, to a lesser extent 2-1-2, increases the resilience of frozen-thawed bull sperm when applied upon thawing.
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Bibliography


Abdel-Salam Z, Dessouki SH, Abdel-Salam SA, Ibrahim MA, Harith MA (2011) Green laser irradiation effects on buffalo semen. Theri-ogenology 75: 988-994.
Aitken RJ (1997) Molecular mechanisms regulating human sperm function. Mol Hum Reprod 3: 169-173.
Aitken RJ, West K M (1990) Analysis of the relationship between reactive oxygen species production and leucocyte infiltration in fractions of human semen separated on Percoll gradients. Int J Androl 13: 433-451.
Antognazza MR, Abdel Aziz I, Lodola F (2019) Use of Exo- genous and Endogenous Photomediators as Efficient ROS Modulation Tools: Results and Perspectives for Therapeutic Purposes. Oxid Med Cell Longev 2019: 2867516.
Avci P, Gupta A, Sadasivam M, Vecchio D, Pam Z, Pam N, Hamblin MR (2013) Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring. Semin Cutan Med Surg 32: 41-52.
Brand˜ao AC, Arruda RP, Andrade AF, Zaffalon FG, Tarrag´o OF, Visintin JA, Assumpção ME (2008) Effect of diode laser on motility, plasma and acrosomal membrane integrity, and mitochondrial membrane potential of cryopreserved stallion spermatozoa. Anim Reprod Sci 107: 309-310.
Breitbart H, Levinshal T, Cohen N, Friedmann H, Lubart R (1996) Changes in calcium transport in mammalian sperm mitochondria and plasma membrane irradiated at 633 nm (He-Ne laser). J Photochem Photobiol B 34: 117-121.
Bucak MN, Sariozkan S, Tuncer PB, Sakin F, Atessahin A, Kulaksiz R, Cevik M (2010) The effect of antioxidants on post-thawed Angora goat (Capra hircus ancryrensis) sperm parameters, lipid peroxidation and antioxidant activities. Small Rumin Res 89: 24-30.
Cohen N, Lubart R, Rubinstein S, Breitbart H (1998) Light irradiation of Mouse spermatozoa: Stimulation of in vitro fertilization and calcium signals. Photochem Photobiol 68: 407-413.
Corral-Baqués MI, Rivera MM, Rigau T, Rodríguez-Gil JE, Rigau J (2009) The effect of low-level laser irradiation on dog spermatozoa motility is dependent on laser output power. Lasers Med Sci 24: 703-713.
Cui L, Li XY, He DY, Chen L, Gong SL (2013) Study on microtexture of laser welded 5A90 aluminium-lithium alloys using electron backscattered diffraction. Sci Technol Weld 18: 204–209.
Dall Agnol MA, Nicolau RA, de Lima CJ, Munin E (2009) Comparative analysis of coherent light action (laser) versus non-coherent light (light-emitting diode) for tissue repair in diabetic rats. Lasers Med Sci 24: 909-916.
Darszon A, Treviño CL, Wood C, Galindo B, Rodríguez- -Miranda E, Acevedo JJ, Hernández-González EO, Beltrán C, Martínez-López P, Nishigaki T (2007) Ion channels in sperm motility and capacitation. Soc Reprod Fertil Suppl 65: 229-244.
de Almeida TG, Alves MB, Batissaco L, Torres MA, de Andrade AF, Mingoti RD, de Arruda RP, Celeghini EC (2019) Does low-level laser therapy on degenerated ovine testes improve post-thawed sperm characteristics? Lasers Med Sci 34: 1001-1009.
de Rezende MU, Varone BB, Martuscelli DF, Ocampos GP, Freire GM, Pinto NC, de Sousa MV (2022) Pilot study of the effect of therapeutic photobiomodulation on postoperative pain in knee arthroplasty. Braz J Anesthesiol 72: 159-161
Desan PH, Weinstein AJ, Michalak EE, Tam EM, Meesters Y, Ruiter M J, Horn E, Telner J, Iskandar H, Boivin DB, Lam RW (2007) A controlled trial of the Litebook light- -emitting diode (LED) light therapy device for treatment of Seasonal Affective Disorder (SAD). Bmc Psychiatry 7(1): 1-8.
Fekrazad E, Keyhan H, Fekrazad R, Tajik A (2014) Effect of Diode Lasers on Human Sperm Motility. Acad Res Int 5: 21-25.
Fernandes GH, de Carvalho PD, Serra AJ, Crespilho AM, Peron JP, Rossato C, Leal-Junior EC, Albertini R (2015) The effect of low-level laser irradiation on sperm motility, and integrity of the plasma membrane and acrosome in cryopreserved bovine sperm. PLoS One 10: e0121487.
Frangez HB, Frangez I, Verdenik I, Jansa V, Klun IV (2015) Photobiomodulation with light-emitting diodes improves sperm motility in men with asthenozoospermia. Lasers Med Sci 30: 235-240.
Garner DL, Johnson LA (1995) Viability assessment of mammalian sperm using SYBR-14 and propidium iodide. Biol Reprod 53: 276-284.
Huang YY, Nagata K, Tedford CE, McCarthy T, Hamblin MR (2013) Low-level laser therapy (LLLT) reduces oxidative stress in primary cortical neurons in vitro. J Biophotonics 6: 829-838.
Iaffaldano N, Meluzzi A, Manchisi A, Passarella S (2005) Improvement of stored turkey semen quality as a result of He-Ne laser irradiation. Anim Reprod Sci 85: 317-325.
Iaffaldano N, Paventi G, Pizzuto R, Di Iorio M, Bailey JL, Manchisi A, Passarella S (2016) Helium-neon Laser Irradiation of Cryopreserved Ram Sperm Enhances Cytochrome C Oxidase Activity and ATP Levels Improving Semen Quality. Theriogenology 86: 778-784.
Iaffaldano N, Rosato MP, Paventi G, Pizzuto R, Gambacorta M, Manchisi A, Passarella S (2010) The irradiation of rabbit sperm cells with He-Ne laser prevents their in vitro liquid storage dependent damage. Anim Reprod Sci 119: 123-129.
Kim CH, Ahn DC (2012) Coaxial monitoring of keyhole during Yb:YAG laser welding. Opt Laser Technol 44: 1874-1880.
Lubart R, Wollman Y, Friedmann H, Rochkind S, Laulicht I (1992) Effects of visible and near infrared lasers on cell cultures. J Photochem Photobiol B 12: 305-310.
Maia MS, Bicudo SD, Sicherle CC, Rodello L, Gallego IC (2010) Lipid peroxidation and generation of hydrogen peroxide in frozen-thawed ram semen cryopreserved in extenders with antioxidants. Anim Reprod Sci 122: 118-123.
Muiño R, Tamargo C, Hidalgo CO, Peña AI (2008) Identification of sperm subpopulations with defined motility characteristics in ejaculates from Holstein bulls: effects of cryopreservation and between-bull variation. Anim Reprod Sci 109: 27-39.
Nagy S, Jansen J, Topper EK, Gadella BM (2003) A triple- -stain flow cytometric method to assess plasma- and acrosome-membrane integri-ty of cryopreserved bovine sperm immediately after thawing in presence of egg-yolk particles. Biol Reprod 68: 1828-1835.
Ocaña-Quero JM, Gomez-Villamandos R, Moreno-Millan M, Santisteban-Valenzuela JM (1997) Biological effects of helium-neon (He-Ne) laser irradiation on acrosome reaction in bull sperm cells. J Photochem Photobiol B 40: 294-298.
Omur A, Balcı S (2020) Evaluatıon of the effects of photostimulation on freze-thawed bull sperm cells in terms of motility: preliminary as-sessment. CRYO2020 The 57th Annual Meeting Of The Society For Cryobiology. July 21-23. 97: 289-290
Omur AD, Coyan K (2016) Protective effects of the antioxidants curcumin, ellagic acid and methionine on motility, mitochondrial transmem-brane potential, plasma membrane and acrosome integrity in freeze-thawed Merino ram sperm. Vet Med 61: 10-16.
Pezo F, Zambrano F, Uribe P, Ramírez-Reveco A, Romero F, Sanchéz R (2018) LED-based red light photostimulation improves short-term response of cooled boar semen exposed to thermal stress at 37°C. Andrologia 51: e13237.
Prieto-Martínez N, Morató R, Muiño R, Hidalgo CO, Rodríguez-Gil JE, Bonet S, Yeste M (2017) Aquaglyceroporins 3 and 7 in bull spermatozoa: identification, localisation and their relationship with sperm cryotolerance. Reprod Fertil Dev 29: 1249-1259.
Rashid K, Sil PC (2015) Curcumin ameliorates testicular damage in diabetic rats by suppressing cellular stress mediated mitochondria and endoplasmic reticulum dependent apoptotic death. Biochim Biophys Acta 1852: 70-82.
Rodríguez-Gil JE (2019) Photostimulation and thermotaxis of sperm: Overview and practical implications in porcine reproduction. Theriogenology 137: 8-14.
Saltmarche AE (2008) Low level laser therapy for healing acute and chronic wounds-the extendicare experience. Int Wound J 5: 351-360.
Soares LE, Guirado MM, Berlingieri G, Ramires MC, Lyra LA, Teixeira IS, Oliveira, PC, Tateno RY, Palma LF, Campos L (2021) Intranasal photobiomodulation therapy for COVID-19-related olfactory dysfunction: a Brazilian multicenter case series. Photodiagnosis Photodyn Ther 36: 102574.
Wenbin Y, Wenzhong L, Mengzhao L, Baotian Z, Laizeng AI, Tongya L (1996) Effects of laser radiation on Saanen buck’s sperm energy metabolism. In: Proceedings of the sixth ınternational conference on goats. Beijing, China.
Wright C, Milne S, Leeson H (2014) Sperm DNA damage caused by oxidative stress: modifiable clinical, lifestyle and nutritional factors in male infertility. Rep Biomed Online 28: 684-703.
Yeste M, Codony F, Estrada E, Lleonart M, Baslasch S, Peña A, Bonet S, Rodríguez-Gil JE (2016) Specific LED-based red light photo-stimulation procedures improve overall sperm function and reproductive performance of boar ejaculates. Sci Rep 6: 22569.
You DY, Gao XD, Katayama S (2014) Review of laser welding monitoring. Sci Technol Weld Join 19: 181-201.
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Authors and Affiliations

A.D. Ömür
1 2 3

  1. Department of Reproduction and Artificial Insemination, Faculty of Veterinary Medicine, Atatürk University, 25240, Yakutiye/ Erzurum, Turkey
  2. Department of Biochemistry, Faculty of Veterinary Medicine, Atatürk University, 25240, Yakutiye/Erzurum, Turkey
  3. Department of Molecular Biology and Genetics, Faculty of Science, Atatürk University, 25240, Yakutiye/Erzurum, Turkey
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Abstract

Testicular torsion is a frequently encountered clinical condition that requires urgent treatment. The aim of this study is to investigate the efficacy of Anise (Pimpinella anisum L.) in treating the pathological condition due to ischemia and reperfusion injury by using biochemical, histopathological and immunohistochemical methods.
A total of 6 groups were formed with 8 male Wistar Albino rats in each group. Group 1 (n=8): control group, Group 2 (n=8): Anise aqueous solution was given orally 5 ml/kg by gavage for 30 days. Group 3 (n=8): Ischemia and Reperfusion (I/R) group, bilateral testicles were rotated 270° and reperfused after 30 minutes of ischemia. Group 4 (n=8): I/R+ Anise group, Group 5 (n=8): Anise+ I/R group and Group 6 (n=8): Anise+ I/R+ Anise group.
The results of the Anise group and the Control group were similar. However, the damage in the I/R group was considerably more severe than in any of the other study groups. While it was observed that spermatogenic cells started to regenerate in the I/R+Anise group, edema and congestion were observed in the Anise+I/R group. In the Anise+I/R+Anise group, all histological findings and biochemical parameters were similar to those of the control group.
It was observed that anise had protective effects in ischemia and reperfusion injury in rat testicles.
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Authors and Affiliations

E. Yildizhan
1
M. Akkus
1
B.V. Ulger
2
F. Asır
1
S. Söker
1
E. Gündüz
3
M. Rençber
4
M. Barçin
2

  1. Dicle University, Faculty of Medicine, Department of Histology and Embryology, Kıtılbıl Mah. 21280, Diyarbakır, Turkey
  2. Dicle University, Faculty of Medicine, Department of General Surgery, Kıtılbıl Mah. 21280, Diyarbakır, Turkey
  3. Dicle University, Faculty of Medicine, Department of Emergency Medicine, Kıtılbıl Mah. 21280, Diyarbakır, Turkey
  4. Department of General Surgery, Viransehir State Hospital, Ceylanpınar Yolu No:3, 63700 Viranşehir/Şanlıurfa, Turkey
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Abstract

Starting from a subjective viewpoint on the decreasing interest in invertebrate fossil taxonomy, this essay discusses its importance in palaeobiological studies exemplified with cases from the palaeobiogeography and palaeoecology of rugose corals, and aims at provoking a discussion on the topic. The possible causes of this negative declining trend include inherent problems of palaeontological taxonomy, and changing systems in science and higher education.
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Bibliography


Arrigoni, R., Berumen, M.L., Chen, C.A., Terraneo, T.I., Baird, A.H., Payri, C. and Benzoni, F. 2016. Species delimitation in the reef coral genera Echinophyllia and Oxypora (Scleractinia, Lobophylliidae) with a description of two new species. Molecular Phylogenetics and Evolution, 105, 146–159.
Baird, A.H., Hoogenboom, M.O. and Huang, D. 2017. Cyphastrea salae, a new species of hard coral from Lord Howe Island, Australia (Scleractinia, Merulinidae). ZooKeys, 662, 49–66.
Bamber, E.W., Rodríguez, S., Richards, B.C. and Mamet, B. 2017. Uppermost Viséan and Serpukhovian (Mississippian) rugose corals and biostratigraphy. Canadian Cordillera. Palaeontographica Canadiana, 36, 1–169.
Berkowski, B. and Zapalski, M.K. 2018. Large dwellers of the Silurian Halysites biostrome: rhizosessile life strategies of cystiphyllid rugose corals from the Llandovery of Gotland. Lethaia, 51, 581–595.
Billings, E. 1858. Report for the year 1857. Report of Progress, 147–192. Geological Survey of Canada; Montreal.
Cowman, P.F., Quattrini, A.M., Bridge, T.C.L., Watkins-Colwell, G.J., Fadli, N., Grinblat, M., Roberts, T.E., McFadden, C.S., Miller, D.J. and Baird, A.H. 2020. An enhanced target-enrichment bait set for Hexacorallia provides phylogenomic resolution of the staghorn corals (Acroporidae) and close relatives. Molecular Phylogenetics and Evolution, 153, 106944.
Dana, J.D. 1846–1849. Zoophytes. United States Exploring Expedition during the years 1838–1842, 7, 740 pp. Lea and Blanchard; Philadelphia.
Fedorowski, J. 1980. Some aspects of coloniality in corals. Acta Palaeontologica Polonica, 25, 429–437.
Fedorowski, J. 1986. The rugose coral faunas of the Carboniferous/ Permian boundary interval. Acta Palaeontologica Polonica, 31, 394–402.
Fedorowski, J. 1997. Diachronism in the development and extinction of Permian Rugosa. Geologos, 2, 59–164.
Fedorowski, J. 2019. Bashkirian Rugosa (Anthozoa) from the Donets Basin (Ukraine). Part 7. The Family Neokoninckophyllidae Fomichev, 1953, with a preliminary revision of Moscovian taxa. Acta Geologica Polonica, 69, 59–81.
Fedorowski, J. and Bamber, E.W. 2007. Remarks on lithostrotionid phylogeny in western North America and western Europe. In: Hubman, B. and Piller, W.E. (Eds), Fossil corals and sponges. Proceedings of the 9th International Symposium on Fossil Cnidaria and Porifera, Graz, 2003. Österreichische Akademie der Wissenschaften. Schriftenreihe der Erdwissenschaftlichen Kommissionen, 17, 251–273.
Fedorowski, J., Bamber, E.W. and Richards, B.C. 2019. Bashkirian rugose corals from the Carboniferous Mattson Formation in the Liard Basin, northwest Canada – stratigraphic and paleobiogeographic implications. Acta Palaeontologica Polonica, 64, 851–870.
Fedorowski, J., Bamber, E.W. and Stevens, C.H. 2007. Lower Permian colonial rugose corals, Western and Northwestern Pangaea: Taxonomy and distribution, 231 pp. National Research Council of Canada Research Press; Ottawa.
Garcia-Bellido, D.C. and Rodríguez, S. 2005. Palaeobiogeographical relationships of poriferan and coral assemblages during the late Carboniferous and the closure of the western Palaeotethys Sea-Panthalassan Ocean connection. Palaeogeography, Palaeoclimatology, Palaeoecology, 219, 321– 331.
Gómez-Herguedas, A. and Rodríguez, S. 2009. Paleoenvironmental analysis based on rugose corals and microfacies: a case study at La Cornuda section (Early Serpukhovian, Guadiato Area, SW Spain). Lethaia, 42, 39–54.
Groot, G. de 1963. Carboniferous corals of northern Palencia (Spain). Leidse Geologische Mededelingen, 29, 1–124.
Hill, D. 1981. Coelenterata, Supplement 1, Rugosa and Tabulata. In: Teichert, C. (Ed.), Treatise on Invertebrate Paleontology, Part F, 762 pp. Geological Society of America and University of Kansas Press; Lawrence.
Humboldt, A. v. and Bonpland, A. 1805–1829. Voyage aux régions équinoxiales du Nouveau Continent, fait de 1799 à 1804. Maze; Paris.
Kelly, W.A. 1942. Lithostrotionidae in the Rocky Mountains. Journal of Paleontology, 16, 351–361.
Kitahara, M.V., Capel, K.C.C. and Migotto, A.E. 2020. Coenocyathus sebroecki sp. nov.: a new azooxanthellate coral (Scleractinia, Caryophylliidae) from southeastern Brazil. Marine Biodiversity, 50 (4), 1–9.
Kitahara, M.V., Fukami, H., Benzoni, F. and Huang, D. 2016. The new systematics of Scleractinia: integrating molecular and morphological evidence. In: Goffredo, S. and Dubinsky, Z. (Eds), The Cnidaria, past, present and future: The world of Medusa and her sisters, 41–59. Springer; Cham.
Lamarck, J.-B. M. de. 1816. Histoire naturelle des animaux sans vertèbres. Tome second, 568 pp. Verdière; Paris.
Linnæus, C. 1766–1767. Systema naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Ed. 12. 1, Regnum Animale, 1 and 2, pp. 1–532 [1766], pp. 533–1327 [1767]. Laurentii Salvii; Holmiae.
Lonsdale, W. 1845. Description of some characteristic Palaeozoic corals from Russia, Vol. 1. In: Murchison, R.I., Verneuil, E. de and Keyserling, A. v. (Eds), The Geology of Russia in Europe and the Ural Mountains, 591–634. Murray; London.
McCoy, F. 1849. On some new genera and species of Carboniferous corals and Foraminifera. Annals and Magazine of Natural History, Series 2, 3, 1–20.
Milne Edwards, H. and Haime, J. 1848. Mémoire 2. Monographie des turbinolides. Annales des Sciences Naturelles, Zoologie, Series 3, 9, 211–344.
Milne Edwards, H. and Haime, J. 1851. A monograph of British fossil corals, 322 pp. Palaeontographical Society of London; London.
Minato, M. and Kato, M. 1965a. Waagenophyllidae. Journal of the Faculty of Sciences, Hokkaido University. Series 4. Geology and Mineralogy, 12, 1–241.
Minato, M. and Kato, M. 1965b. Durhaminidae. Journal of the Faculty of Sciences, Hokkaido University. Series 4. Geology and Mineralogy, 13, 13–86.
Oliver, W.A. Jr. 1976. Presidential address. Biogeography of Devonian rugose corals. Journal of Paleontology, 50, 365–373.
Oliver, W.A. Jr. and Pedder, A.E.H. 1979. Biogeography of Late Silurian and Devonian rugose corals in North America. In: Gray, J. and Boucot, A.J. (Eds), Historical biogeography, plate tectonics and changing environment, 131–145. Oregon State University Press; Cornvallis.
Orbigny, A. d’ 1852. Cours élémentaire de paleontology et géologie stratigraphique. Vol. 2, 1146 pp. Victor Masson; Paris.
Paz-García, D.A., Hellberg, M.E., García-de-León, F.J. and Balart, E.F. 2015. Switch between morphospecies of Pocillopora corals. The American Naturalist, 186 (3), 434–440.
Rodríguez, S. 1984. Corales rugosos del este des Asturias. Unpublished Ph.D. thesis, 528 pp. Departamento de Paleontologia, Facultad de Ciencias Geológicas, Universidad Complutense de Madrid.
Rodríguez, S. and Kullmann, J. 1999. Rugose corals from the upper member of the Picos de Europa Formation (Moscovian, Cantabrian Mountains, NW Spain). Palaeontographica, Abteilung A, 252, 23–92.
Said, I., Rodríguez, S., Somerville, I.D. and Cózar, P. 2011. Environmental study of coral assemblages from the Upper Viséan Tizra Formation (Adarough Area, Morocco): implication for Western Palaeotethys biogeography. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen, 260, 101–118.
Saville Kent, W. 1871. On some new and little-known species of madrepores, or stony corals, in the British Museum collection. Proceedings of the Scientific Meetings of the Zoological Society of London, 1871, 275–286.
Scotese, C.R. 2001. Atlas of Earth History. Vol. 1. Paleogeography, 52 pp. PALEOMAP Project; Arlington.
Sorauf, J.E. and Kissling, D.L. 2012. Rugosans immured in Silurian Paleofavosites; Brassfield Formation (Llandovery) of Ohio. Geologica Belgica, 5, 220–225.
Torsvik, T.H. and Cocks, L.R.M. 2017. Earth History and Palaeogeography, 317 pp. Cambridge University Press; Cambridge.
Vinn, O. and Mõtus, M.A. 2014. Endobiotic rugosan symbionts in stromatoporoids from Sheinwoodian (Silurian) of Baltica. Plos One, 9, 1–6.
Wang, H.C. 1950. A revision of the Zoantharia Rugosa in the light of their minute skeletal structures. Philosophical Transactions of the Royal Society of London. Series B Biological Sciences, 611, 175–264.
Wedekind, R. 1927. Die Zoantharia Rugosa von Gotland (bes. Nordgotland), Nebst Bemerkungen zur Biostratigraphie des Gotlandium. Sveriges Geologiska Undersökning, 19, 1–94.
Wu, W.S. and Zhou, K.J. 1982. Upper Carboniferous corals from Kalping and Aksu, Xinjiang. Academia Sinica. Nanjing Institute of Geology and Palaeontology, Bulletin, 1982, 213– 239. [In Chinese with English summary]
Ziegler, P.A. 1988. Laurussia – the old red continent. In: Mc- Millan, N.J., Embry, A.F. and Glass, D.J. (Eds), Devonian of the World. 1. Regional synthesis. Proceedings of the Second International Symposium on the Devonian System, 5–48. Canadian Society of Petroleum Geologists; Calgary.
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Authors and Affiliations

Jerzy Fedorowski
1

  1. Institute of Geology, Adam Mickiewicz University, Bogumiła Krygowskiego 12, 61-680 Poznań, Poland
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Abstract

Low manganese and sulfur gray irons were produced by adding inoculant base Fe-Si with small amounts of Al and Ca in the ladle. The effect of the cast thickness, inoculant amount and shakeout time of the green sand molds were studied on the graphite flake formation by microscopically techniques. A thermodynamic analysis was carried out for the cast iron produced with the FactSage 7.2 software. Stability phase diagrams were obtained for both gray cast irons to different manganese (0.1 to 0.9 wt.%) and sulfur (0.01 to 0.12 wt.%) amounts to 1150°C. It was shown that lower amounts of manganese and sulfur allow forming the 3Al2O3·2SiO2, Al2O3, and ZrO2 solid compounds. The thermodynamic results match with those obtained by SEM-EDS. It is possible to form MnS particles in the liquid phase when the solubility product (%Mn) × (%S) equals 0.042 and 0.039 for heats A and B, respectively.

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Authors and Affiliations

G. Reyes-Castellanos
A. Cruz-Ramírez
E. Colin-García
V.H. Gutiérrez-Pérez
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Abstract

New computational procedures developed within the framework of international research projects „Grispe” and „Grispe Plus” are briefly presented and characterised here. Considered algorithms pertain to the verification of bearing capacity and serviceability of selected bearing structure components erected with especially shaped thinwalled sheet metal panels. Structural components of this type are so far rather absent from the codes, and as a result the unequivocal design requirements have not been developed for them. Key problems related to the detailed analysis of the following element classes: steel decks with embossments, indentations and/or outwards stiffeners; liner trays; corrugated sheeting; curved profiles; cladding and roof profile assemblies; perforated and holed profiles; external interlocking planks and their assemblies are indicated in the text. The procedures formulated as a part of the projects indicated above have been delivered to CEN as an official proposal of amendments and/or additions submitted for introduction to the new generation of Eurocodes currently under preparation, and especially as an extension to the code EN 1993-1-3.

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Authors and Affiliations

M. Maslak
M. Pazdanowski
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Abstract

This work deals with the analysis of elasto-plastic post-buckling state of rectangular laminated plates subjected to combined loads, such as uniform compression and shear. The plates are built of specially orthotropic symmetrical layers. The analysis is carried out on the basis of nonlinear theory of orthotropic plates involving plasticity. The solution can be obtained in the analytical-numerical way using Prandtl-Reuss equations. The preliminary results of numerical calculations are also presented in figures.
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Authors and Affiliations

Ryszard Grądzki
Katarzyna Kowal-Michalska
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Abstract

The subject of the article is the specific nature of historical narration in digital media (YouTube). Both the media where the Polish state is the channel owner and ones belonging to individual political parties and fractions are being studied. The relationship between the narration and national identity is analyzed. The question under discussion is to what extent national identity is a phenomenon ingrained in the ethnic and historical peculiarities of a given society. The authors contrasts the primordialist concept with Ernest Gellner’s modernist concept. In the second part the authors refer to the discussion about the significance of historical narration for the formation of identity: if historical narration is just an accidental component of identity formation processes or rather a fundamental one.
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Authors and Affiliations

Dawid Gralik
1
ORCID: ORCID
Adrian Trzoss
1
ORCID: ORCID
Wiktor Werner
1
ORCID: ORCID

  1. Adam Mickiewicz University, Poznań
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Abstract

The influence of sheeting made by sandwich panels on the lateral-torsional buckling resistance of hot rolled purlin was studied in this paper. The actual shear and torsional stiffness as well as resistance of connections between sandwich panel and purlins were considered in analysis. Parameters of these factors were determined using the finite element method, as well as by own experimental tests. Simple models with beam elements were used in LBA analysis to calculate the critical moments of the purlins. Advanced models with GMNIA analysis using shell elements was performed to simulate the behaviour of the purlins stabilized by sandwich panels. The results show that the stiffness of sheeting made by sandwich panels is insufficient to ensure the full protection of purlin against lateral-torsional buckling. The connections resistance also limited the ability of purlins stabilisation. Nevertheless including sandwich panels in purlin stability analysis results in a significant increase in their LTB resistance.
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Authors and Affiliations

Marcin Górski
1
Aleksander Kozłowski
2

  1. Rzeszów University of Technology, Faculty of Civil and Environmental Engineering and Architecture, ul. Poznańska 2, 35-084 Rzeszów, Poland
  2. Rzeszów University of Technology, Faculty of Civil and Environmental Engineeringand Architecture, ul. Poznańska 2, 35-084 Rzeszów

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