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Abstract

The resistance of winter wheat varieties to Puccinia recondite f. sp. tritici was investigated at the Lithuanian Institute of Agriculture during 2001–2003. Effectiveness of resistance genes was investigated at seedling, tillering and adult plant stages. Virulence tests done during the 2000–2003 period showed that the majority of Lr genes used in European wheat were not sufficiently efficient. However, testing of cultivars at the first leaf stage revealed that the Lr37 gene in combination with the other genes was very effective. The experimental cultivars were sown in 2 times: in autumn and spring, without vernalization. The main task of spring-sown nursery was to improve the effectiveness of the experiment and investigate the effect of different Lr genes of non-vernalized plants at tillering growth stage. The Lr37 gene was found to be the most effective at both adult plant stage and tillering growth stage. Disease severity and plant resistance type at tillering stage were stable in all experimental years, which is important for the breeding program. The investigations revealed that the correlations between resistance at seedling and the other two stages were up to r = 0.81 (significant at p = 0.01**). The correlations between leaf rust severity and varietal resistance type at tillering were very high (r = 0.86–0.91**) in the same year. The correlation of leaf rust severity at adult plant stage was strong (r = 0.78**) between 2001 and 2002, but too low for reliable selection of resistant cultivars in the other years. Spring-sown nursery was complementary to collect resistance data in the years unfavourable for leaf rust development.

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Authors and Affiliations

Žilvinas Liatukas
Vytautas Ruzgas
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Abstract

The knowledge of performance characteristics of turbine stage groups is still insufficient, particularly in the general case of changes of operating conditions. This situation is caused mainly by the scarcity of experimental data available. In such case, the opportunity to obtain the required data, using mathematical modelling and numerical simulation of the operation of stage groups under off-design conditions instead of physical experiment, seems to be attractive. The application of this idea for impulse type turbine stage groups was presented in [I], [2]. Here we discuss similar results but obtained for reaction type turbine stage groups, that is: - mathematical model for computer simulation of operation of reaction type turbine stage group, under variable regime (based on Ainley's and Mathieson's method with some improvements); - simulation results for a number of stage groups designed according to former BBC and traditional concepts; - more general properties of these groups (in relation to flow capacity and efficiency) obtained from the analysis of simulation data; - comparison of observed properties of impulse and reaction typy turbine stage groups.
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Authors and Affiliations

Andrzej Miller
Janusz Lewandowski
Zofia Trzcińska
Kamal Ahmad Abed
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Abstract

The aim of this study was to determine the ecological characteristics of vascular plants colonizing serpentine mining waste dumps and quarries in Lower Silesia. The investigated flora was analyzed with regard to species composition, geographical-historical status, life forms, as well as selected ecological factors, such as light and trophic preferences, soil moisture and reaction, value of resistance to increased heavy metals content in the soil, seed dispersal modes and occurrence of mycorrhiza. There were 113 species of vascular plants, belonging to 28 families, found on seven sites in the study. The most numerous families were Asteraceae, Poaceae, Fabaceae and Caryophyllaceae. Only 13% of all plants recorded occurred on at least five of the study sites. The most numerous were species related to dry grassland communities, particularly of the Festuco-Brometea class, which included taxa endangered in the region of Lower Silesia: Avenula pratensis, Salvia pratensis, Festuca valesiaca. Apophytes dominated in the flora of the investigated communities. Hemicryptophytes were the most numerous group and therophytes were also abundant. The serpentine mining waste dumps and querries hosted heliophilous species which prefer mesic or dry habitats moderately poor in nutrients, featuring neutral soil reaction. On two study sites 30% of the flora composition consisted of species that tolerate an increased content of heavy metals in the soil. Anemochoric species were the most numerous with regard to types of seed dispersal. Species with an arbuscular type of mycorrhiza were definitely dominant in the flora of all the study sites, however, the number of nonmycorrhizal species was also relatively high. It was suggested that both the specific characteristics of the habitats from serpentine mining and the vegetation of adjacent areas had a major impact on the flora composition of the communities in the investigated sites.

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Authors and Affiliations

Dorota Kasowska
Anna Koszelnik-Leszek
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Abstract

This paper presents the modeling and the resolution of a two dimensional cutting stock problem for a wooden industry. It is about a real problem of minimization of the wood wastes for an industry of furnishing. The raw material to be cut is a set of beams of various sizes. The purpose of the cut is to supply a list of orders characterized by a set of articles of various sizes. The problem is converted into an integer linear program where the decision variables are the numbers of beams to cut according to a set of feasible “patterns”. The designed solution is a heuristic in two stages: – Generation of the feasible patterns by various classic heuristics of the Bin-packing Problem. – Resolution of the integer linear program with the generated patterns as input variables. Moreover, based on this approach, the “Application Cutting Optimization” is developed to allow the immediate resolution of the problem and widening the stock management horizon. To end, a real case is studied to confirm the effectiveness of this approach.
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Authors and Affiliations

Amine Bouaine
Maria Lebbar
Mohamed Ait Ha
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Abstract

What is a Global Stratotype Section and Point (GSSP) benchmark, and what role does it play in delineating geological boundaries?
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Authors and Affiliations

Andrzej Wierzbowski
1

  1. Faculty of Geology, University of Warsaw
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Abstract

The investigation presented in this work concerned one-dimensional modelling of transient flow in an axial turbine stage. Because of the compound motion in the rotor-blade channels, the model of this flow path element was considered the most difficult to solve. The basic modelling approaches and the usefulness of the Euler and Lagrange methods for mathematical description are discussed. Relevant applied model based on the Lagrange method is described. Results of a successful numerical simulation of transient flow in a turbine stage are presented. This success opens the opportunity to build and solve one-dimensional models of dynamic flows in turbine cascades and entire flow paths.
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Authors and Affiliations

Nikołaj Uzunow
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Abstract

This study presents a fuzzy analytic hierarchy process (FAHP) by integrating analytic hierarchy process (AHP) and fuzzy cognition to evaluate the construction risks of tunnel portals. Wuguanyi Tunnel is taken as the research objective to validate the performance of the proposed method. The result shows that the proposed decision making method can effectively identify risk factors and determine the risk level during the construction of tunnel portals. Finally, the corresponding control measures during the construction of the Wuguanyi Tunnel portal are proposed according to the risk assessment results.

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Authors and Affiliations

Xianghui Deng
ORCID: ORCID
Rui Wang
ORCID: ORCID
Tian Xu
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Abstract

The results of a systematic study of the influence of meridional contours overlap in the stator-rotor axial interspace of the impulse and reactive type stages of a high-pressure steam turbine on the flow structure and gas-dynamic efficiency of the flow part are introduced. The studied flow parts of the impulse and reactive stages are typical for high-power high-pressure steam turbines. It is shown that the stages that have no overlaps and/or have a smooth shape of meridional contours have the best gasdynamic efficiency, and the most negative effect on the flow part is caused by the presence of caverns in the stator-rotor interspace. For cases where, due to technological limitations, it is impossible to avoid the presence of caverns and overlaps with a sharp (step-wise) change in the shape of the meridional contours, it is recommended to perform overlaps with positive size of overlap values near the rotor blades.
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Bibliography

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Authors and Affiliations

Andrii Rusanov
1
Roman Rusanov
1

  1. The A. N. Pidgorny Institute of Mechanical Engineering Problems NAS of Ukraine, Dm. Pozharsky 2/10, 61046 Kharkiv, Ukraine
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Abstract

The purpose of the study is to determine the characteristic features of personal functioning at different stages of professional development. The survey involved 139 professionals from various fields (74 women and 65 men) aged 24 to 67 years. The sample is divided into 5 groups according to the stage of professional development. A comparative analysis of groups by parameters of professional self-realisation, emotional burnout and psychological well-being is carried out. The results obtained demonstrate the nonlinear, complex dynamics of self-realisation of the individual throughout life and clarify the internal mechanisms of professional development at each stage. The stages of primary and secondary professionalisation are accompanied by the greatest need for self-improvement and at the same time, exaggerated and unrealistic ideas about one's own professional competence. An increased symptomatology of emotional burnout has been identified, which accompanies the peak of professional excellence and determines the next stage of professional activity decline after 30 years of work experience. The coincidence of the normative age and professional crises entails a profound crisis of the pre-retirement age, which is characterised primarily by a loss of goal-setting. People who continue to work in the post-retirement age have the highest rates of self-fulfillment, which leads to overall satisfaction with life and self. The described patterns open new perspectives for the development of ways of psychological counselling and organisational support of specialists.
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Bibliography

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Bochelyuk, V. Y., Panov, M. S., Shostya, I. V., & Katasanov, O. M. (2016b). Socio-psychological aspects of self-understanding of the individual in professional communication. Theoretical and Applied Problems of Psychology, 3, 26–33. http://tpppjournal.com.ua/contents/n3y2k16folder/n3y2k16a3.html
Bochelyuk, V. Y., Zavatska, N. E., Kononenko, A. O., Novitska, L. V., & Fedorov, A. Y. (2016a). Socio-psychological features of self- realization of the individual in modern society. Severodonetsk: SNU named after V. Dal.
Chen, F.-P., & Oh, H. (2019). Staff views on member participation in a mental health clubhouse. Health and Social Care in the Community, 27(3), 788–796. https://doi.org/10.1111/hsc.12697
Cobos, T. L., & González, M. C. (2021). Professional competences of future teachers of secondary education: Case study of the formative evaluation promoted by e-rubrics in the specialty of physics and chemistry. Profesorado, 25(1), 197–221. https://revistaseug.ugr.es/index.php/profesorado/article/view/8374
Glavinska, O. D., Ovdiyenko, I. M., Brukhovetska, O. V., Chausova, T. V., & Didenko, M. S. (2020). Professional self-realization as a factor in the psychological well-being of specialists of caring professions. Journal of Intellectual Disability – Diagnosis and Treatment, 8, 548–559. https://doi.org/10.6000/2292-2598.2020.08.03.32
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Authors and Affiliations

Vitalii Y. Bocheliuk
1
Liana V. Spytska
2
Iryna V. Shaposhnykova
3
Anastasiia V. Turubarova
4
Mykyta S. Panov
4

  1. Zaporizhzhia Polytechnic National University, Zaporizhzhia, Ukraine
  2. Volodymyr Dahl East Ukrainian National University, Severodonetsk, Ukraine
  3. Kherson State University, Kherson, Ukraine
  4. Khortytsia National Educational Rehabilitation Academy, Khortytsia, Ukraine
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Abstract

In small steam turbines, sometimes the efficiency is not as important as the cost of manufacturing the turbine. The Curtis wheel is a solution allowing to develop a low output turbine of compact size and with a low number of stages. This paper presents three fully dimensional computational fluid dynamics cases of a Curtis stage with full and partial admission. A 1 MW steam turbine with a Curtis stage have been designed. The fully admitted stage reaches a power of over 3 MW. In order to limit its output power to about 1 MW, the partial admission was applied. Five variants of the Curtis stage partial admission were analyzed. Theoretical relations were used to predict the partial admission losses which were compared with a three-dimensional simulations. An analysis of the flow and forces acting on rotor blades was also performed.
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Bibliography

[1] Achille M., Cardarelli S., Pantano F., Zito M.: Design and CFD analysis of a Curtis turbine stage. In: Proc. 29th Int. Conf. on Efficiency, Cost, Optimisation, Simulation and Environmental Impact of Energy Systems, ECOS 2016, Portorož, June 19–23, 2016.
[2] Rashid S., Tremmel M., Waggott J., Moll R.: Curtis stage nozzle/rotor aerodynamic interaction and the effect on stage performance. J. Turbomach. 129(2007), 3, 551–562
[3] Perycz S.: Steam and Gas Turbines. Ossolineum, Wrocław 1992.
[4] Surwilo J., Lampart P., Szymaniak M.: CFD analysis of fluid flow in an axial multi-stage partial-admission ORC turbine. Open Eng. 5(2015), 1, 360–364.
[5] Kosowski K., Piwowarski M., Włodarski W., Stepien R.: A multistage turbine for a micro power plant. In: Proc. IFToMM Int. Symp. on Dynamics of Steam and Gas Turbines (R. Rzadkowski, Ed.), Gdansk, 1-3 Dec., 2009, Wydawn. IMP PAN, Gdansk 2009, 283–290.
[6] Pan Y., Yuan Q., Zhu G.: Numerical Investigation on the Influence of Inlet Structure on Partial-admission Losses. Proc. Chin. Soc. Electr. Eng. 38(2018), 14, 4156– 4164.
[7] Sakai N., Harada T., Imai Y.: Numerical study of partial admission stages in steam turbine. JSME Int. J. B-Fluid T. 49(2006), 2, 212–217.
[8] Lampart P., Szymaniak M., Rzadkowski R.: Unsteady load of partial admission control stage rotor of a large power steam turbine. In Proc. ASME Turbo EXPO 2004, Power for Land, Sea and Air, Vienna, June 14–17, 2004, ASME GT-2004- 53886, 2004.
[9] Koprowski A., Rzadkowski R.: Computational fluid dynamics analysis of 1 MW steam turbine inlet geometries. Arch. Thermodyn. 42(2021), 1, 35–55.
[10] Rusanov A., Rusanov R.: The influence of stator-rotor interspace overlap of meridional contours on the efficiency of high-pressure steam turbine stages. Arch. Thermodyn. 42(2021), 1, 97–114.
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[17] Wagner W., Pruss A.: The IAPWS formulation 1995 for the thermodynamic properties of ordinary water substance for general and scientific use. J. Phys. Chem. Ref. Data 31(2002), 2, 387–535
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Authors and Affiliations

Arkadiusz Koprowski
1
Romuald Rządkowski
1 2

  1. Institute of Fluid-Flow Machinery Polish Academy of Sciences, Fiszera 14, 80-952 Gdansk, Poland
  2. Air Force Institute of Technology, Ksiecia Bolesława 6, 01-494 Warsaw, Poland
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Abstract

Systematic attempts to maximise the efficiency of gas turbine units are achieved, among other possibilities, by increasing the temperature at the inlet to the expansion section. This requires additional technological solutions in advanced systems for cooling the blade rows with air extracted from the compressor section. This paper introduces a new mathematical model describing the expansion process of the working medium in the turbine stage with air film cooling. The model includes temperature and pressure losses caused by the mixing of cooling air in the path of hot exhaust gases. The improvement of the accuracy of the expansion process mathematical description, compared with the currently used models, is achieved by introducing an additional empirical coefficient estimating the distribution of the cooling air along the profile of the turbine blade. The new approach to determine the theoretical power of a cooled turbine stage is also presented. The model is based on the application of three conservation laws: mass, energy and momentum. The advantage of the proposed approach is the inclusion of variable thermodynamic parameters of the cooling medium. The results were compared with the simplified models used in the literature: separate Hartsel expansion, mainstream pressure, weighted-average pressure and fully reversible. The proposed model for expansion and the determination of theoretical power allows for accurate modelling of the performance of a cooled turbine stage under varying conditions.
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Authors and Affiliations

Paweł Trawiński
1

  1. Institute of Heat Engineering, Warsaw University of Technology, Nowowiejska 21/25, 00-665, Warsaw, Poland
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Abstract

The current survey was carried out to evaluate the effect of different nitrogen levels (0, 2.1, 3.0, 3.9 g ∙ pot–1 nitrogen as urea 46%) on tomato fruit worm Helicoverpa armigera on six common tomato cultivars (e.g., Kingston, Riogrand, Earlyurbana, Redston, Superstrain-B and Primoearly) under laboratory conditions [25 ± 1°C, 60 ± 5% RH, 16 : 8 (L : D) h]. The mortality, developmental period of immature stages as well as the longevity and fecundity of adult stages were recorded. Data were analyzed based on the age-stage, two-sex lifetable theory. The longest (24.21 ± 0.59 days) larval developmental period was recorded in Earlyurbana variety with zero nitrogen level and the shortest (15.44 ± 0.36 days) in Superstrain-B variety with the highest nitrogen level. Consequently, the net reproductive rate (R0) ranged from 35.7 ± 7.06 to 62.16 ± 18.9 offspring/female/individual in Redston variety with zero nitrogen level and in Superstrain-B variety with the highest nitrogen level, respectively. The lowest and highest values of the intrinsic rate (r) and finite rate of increase (l) were estimated for Redston variety with zero level of nitrogen (0.0712 ± 0.0065 and 1.0732 ± 0.0069 day–1) and Superstrain-B variety with the highest nitrogen fertilizer (0.1507 ± 0.0057 and 1.1629 ± 0.0066 day–1), respectively. The results demonstrated that nitrogen fertilizer influenced nearly all the life parameters of the pest which depended on the cultivars. Finally, it could be concluded that Kingston and Superstrain-B were suitable and Earlyurbana and Redston were unsuitable host plant cultivars for H. armigera.

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Authors and Affiliations

Fereshteh Salehi
Gholamhossein Gharekhani
Jalal Shirazi
Nahid Vaez
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Abstract

The root-knot nematode Meloidogyne graminicola is an economically important pest in rice production. The identification of a nematode species is an important basis in nematode management to reduce yield losses by extracting nematode DNA as an early step in molecular identification. This study aimed to investigate the optimal extraction method and number of M. graminicola for nematode genomic analysis based on PCR (polymerase chain reaction) and Sanger sequencing. The DNA extraction methods used in this study were the CTAB, SDS, and commercial kit (GeneAidTM Tissue/Blood DNA Mini Kit). The results revealed that the three DNA extraction methods could be used to analyze the nematode genomics based on PCR and Sanger sequencing using one nematode, both in a second-stage juvenile and a female, equipped with the process of nematode destruction by freezing. This finding was shown by the amplification of all DNA templates with Mg-F3 and Mg-R2 primers through PCR with a size of 370 bp, while Sanger sequencing obtained 372 bp.
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Authors and Affiliations

Rendyta Morindya
1
Siwi Indarti
1
Alan Soffan
1
ORCID: ORCID
Sedyo Hartono
1

  1. Plant Protection, Faculty of Agriculture, Universitas Gadjah Mada, Yogyakarta, Indonesia
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Abstract

Paper is considering the purpose and the process of development of last stage blade for intermediate pressure module of 13K215 steam turbine. In the last 20–30 years most of the steam turbine manufacturers were focused on improving such a turbine mainly by upgrading low pressure module. In a result of such a modernization technology were changed from impulse to reaction. The best results of upgrading were given by developing low pressure last stage blade. With some uncertainty and based on state of art knowledge, it can be stand that improving of this part of steam turbine is close to the end. These above indicators show an element on which future research should be focused on – in the next step it should be intermediate pressure module. In the primary design the height of intermediate pressure last stage blade was 500 mm but because of change of technology this value was decreased to 400 mm. When to focus on reaction technology, the height of the last stage blade is related to output power and efficiency. Considered here is the checking the possibility of implementing blades, in a reaction technology, higher than 400 mm and potentially highest. Article shows a whole chosen methodology of topic described above. It leads through the reasons of research, limitations of 13K215 steam turbine, creation of three-dimensional models, fluid flow calculations, mechanical integrity calculations and proposed solutions of design.
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Bibliography

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Authors and Affiliations

Radoslaw Bondyra
1
Jan Przytulski
1
Krzysztof Dominiczak
2

  1. GE Power Ltd, Stoczniowa 2, 82-300 Elblag, Poland
  2. Institute of Fluid Flow Machinery Polish Academy of Sciences, Fiszera 14, 80-231 Gdansk, Poland
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Abstract

The population dynamics of Tetranychus urticae (two-spotted spider mite – TSSM) are influenced by environmental factors, which were investigated to identify methods limiting the development and harmfulness of this pest. This paper presents findings from a laboratory study on the effect of spraying with water-based extracts of Mentha piperita and Tagetes patula plants on the growth rate of TSSM larvae and nymphs. The time required for the transformation of the larvae into protonymphs was longer for T. patula water- based extracts than extracts from M. piperita. Differences in the time of transformation from the nymphal stage to adult TSSM were also observed depending on the plant waterbased extracts, their concentration, and the host plant on which nymphs were developing. The use of 100 g ∙ l-1 French marigold extract was associated with longer transformation time of nymphs on discs of pea leaves than all tested concentrations of French marigold extract applied to sugar beet leaves. Ten percent of the extracts from peppermint plants had a stronger limiting effect on TSSM nymphs on pea leaves than on bean or sugar beet leaves.
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Authors and Affiliations

Magdalena Jakubowska
1
ORCID: ORCID
Renata Dobosz
2
ORCID: ORCID
Alicja Szabelska-Beręsewicz
3
ORCID: ORCID
Joanna Zyprych-Walczak
3
ORCID: ORCID
Jolanta Kowalska
4
ORCID: ORCID
Anna Tratwal
1
ORCID: ORCID

  1. Department of Monitoring and Signalling of Agrophages, Institute of Plant Protection –National Research Institute, Poznań, Poland
  2. Department of Entomology and Animal Pests, Institute of Plant Protection – National Research Institute, Poznań, Poland
  3. Department of Mathematical and Statistical Methods, Poznań University of Life Sciences, Poznań, Poland
  4. Department of Organic Agriculture and Environmental Protection, Institute of Plant Protection – National Research Institute, Poznań, Poland
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Abstract

Plant responses to glyphosate applied at different doses were examined for one glyphosate resistant (R) and one glyphosate susceptible (S) population of Conyza albida and C. bonarienis. Growth rates and development stages of five R C. albida and three R C. bonarienis populations were also compared with those of their respective S counterparts to investigate the possible impact of the glyphosate resistance trait on their fitness. The GR50 values for C. albida R (3.94−5.22 kg a.i. · ha−1) and S (0.24−0.31 kg a.i. · ha−1) populations were higher than those of C. bonariensis R (0.60−1.51 kg a.i. · ha−1) and S (0.10−0.13 kg a.i. · ha−1). The growth rate (slope b) of one R C. albida population was lower than the respective S and other R populations, while growth rates of most R and S C. bonariensis populations were similar. Some R populations showed inconsistent differences in some development stages when compared to those of the S ones, which cannot be attributed to the glyphosate resistance trait.

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Authors and Affiliations

Philippos N. Mylonas
Costas N. Giannopolitis
Panagiotis G. Efthimiadis
Georgios C. Menexes
Ilias G. Eleftherohorinos
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Abstract

All plants contain varying levels of phenolic acids (metabolites) thus playing an important role in resistance mechanisms as constituents of cell walls, as constitutive antimicrobial compounds of plants or induced in response to infection against many diseases, in particular fusarium head blight caused by Fusarium species. To this end, the objective of this research was to study the variation in phenolic acid composition during the kinetics of filling wheat grains, in order to determine the best variety resistant to fusarium head blight. For this purpose, free and bound phenolic analyses were carried out by HPLC-DAD on five durum wheat varieties at the stage 5 to 8 days after the flowering stage (early grains). We showed that at the level of the samples analyzed, several phenolic acids were present at different concentrations, but others were absent [ cis-ferulic acid (free phenolic acid), and sinapic acid (bound phenolic acid)]. The results also showed that the content of bound phenolic acids was much higher than that of free phenolic acids in all varieties. In addition, these phenolic acids existed in free soluble form or were mostly present in insoluble form bound to cell walls. For free acids, the results showed that significant amounts of transferulic acid were detected in comparison to all free phenolic acids (56.72 μg · g –1 DM for G10). For bound acids, ferulic acid is the main bound phenolic acid which has much higher levels (4913.92 μg · g –1 DM for G1), followed by p-coumaric acid (3098.99 μg · g–1 DM for G1). Moreover, the sum of monomers (bound acids) was much higher than that of dehydrodiferulic acids (DiFA).
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Authors and Affiliations

Salah Hadjout
1 2
Mohamed Zouidi
1
Saïfi Merdas
1

  1. Centre de Recherche en Aménagement du Territoire, CRAT, Campus Universitaire Zouaghi Slimane, Constantine, Algérie
  2. Ecole Nationale Supérieure Agronomique, ENSA, El-Harrach, Alger, Algérie
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Abstract

On the basis of the obtained expeditionary data, the authors performed a comprehensive analysis of the ecosystems’ modern transformation in the studied area. In the course of the analysis, the authors found that at the present stage there have been quantitative changes (depletion of natural resources) in used landscapes, along with them, there are changes in qualitative characteristics (accumulation of resources). Now, against the background of vegetation and soil degradation, ways of their restoration are observed. New combinations of degraded and self-recovering ecosystems have emerged. Based on the analysis of the current state of different ecological systems and their relationships, the authors determined the possibilities of the dynamics of their combinations functioning by stages. This will make it possible to give a more reliable forecast of the ongoing processes in the ecosystems of the Republic of Kazakhstan.
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Authors and Affiliations

Tilepbergen Ryspekov
1
ORCID: ORCID
Marzhan Balkozha
2
ORCID: ORCID

  1. Kazakh National Agrarian Research University, Faculty of Agrobiology, Almaty, Kazakhstan
  2. Kazakh National Agrarian Research University, Faculty of Water, Land and Forest Resources, 8 Abai Ave, 050010, Almaty, Kazakhstan
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Abstract

The impact of Garnet addition into the AL7075 Aluminium matrix on the physical, mechanical and corrosion properties are studied in this research paper. Al 7075/garnet composites are fabricated by using two-stage stir casting method in different (0, 5, 10, 15) volume percentages. Photomicrograph of prepared samples revealed the uniform distribution of garnet reinforcement into the base matrix. The corrosion rate is calculated by potentiodynamic polarization method. The actual density is increased by around 1.2% for Al 7075 / garnet (15%) composite as compared to base alloy. Micro hardness of Al 7075 / garnet (15%) composite is raised by around 47 (34%) compare to as cast base matrix. Al7075 / garnet (15%) composite tensile strength stood at 252 Mpa, which is 40% greater than the base alloy. Al 7075 / 15% garnet composites reduce around 97% of corrosion rate than the base matrix. Alloy elements influenced the corrosion than Garnet reinforcement.
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Bibliography

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Authors and Affiliations

M. Sambathkumar
1
ORCID: ORCID
P. Navaneethakrishnan
1
ORCID: ORCID
K.S.K. Sasikumar
1
ORCID: ORCID
R. Gukendran
1
ORCID: ORCID
K. Ponappa
2
ORCID: ORCID

  1. Kongu Engineering College, Department of Mechanical Engineering, Erode, Tamilnadu, India
  2. Indian Institute of Information Technology Design and Manufacturing Jabalpur, Department of Mechanical Engineering, Jabalpur, India
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Abstract

I n t r o d u c t i o n: A high neutrophil-to-lymphocyte ratio (NLR) has been reported to be a strong biomarker of inflammation.

A i m: We sought to evaluate the impact of NLR on long-term all-cause and cardio-vascular (CV) mortality in hemodialysis (HD) patients.

Ma t e r i a l a n d Me t h o d s: A total of 84 chronic kidney disease (CKD) stage 5 patients with 54 of them on HD, with a median age of 61.5 (51.3–74.8) years were enrolled. The association between NLR and clinical biomarkers was investigated. Multivariable Cox regression analysis was used to find significant predictors of all-cause and CV mortality at follow-up.

R e s u l t s: The median NLR (interquartile range) was 3.0 (2.1–4.1). Patients with NLR ≥3.9 (the highest tertile) had higher five-year all-cause mortality then remaining patients (53.6% vs. 30.4%; p = 0.039). On the contrary, only a trend towards increased CV mortality was observed (25.0% vs. 42.9%; p = 0.10). NLR ≥3.9 was a significant predictor of all-cause mortality at five years [hazard ratio (95%CI): 2.23 (1.10– 4.50); p = 0.025] in Cox regression model adjusted for age, gender, and diabetes status. Similarly, while using NLR as continuous variable a significant association between NLR and all-cause mortality was confirmed even after adjustment for covariates [hazard ratio per 1 unit increase (95%CI): 1.26 (1.06–1.51); p = 0.009] with the area under the receiver operating characteristic (ROC) curve of 0.64. Correlations between NLR and WBC, concentration of fibrinogen, albumin were observed.

C o n c l u s i o n s: Asymptomatic inflammation measured by NLR showed an association with long-term all-cause mortality in stage 5 CKD patients, even while white blood cell count was in the normal range.

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Authors and Affiliations

Karolina Woziwodzka
Artur Dziewierz
Magdalena Pawica
Agnieszka Panek
Marcin Krzanowski
Paulina Gołasa
Paweł Latacz
Magdalena Burkat
Marek Kuźniewski
Katarzyna Krzanowska
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Abstract

The outdoor pot experiments on the influence of weeds' growth stage and climate conditions on herbicides' effect were carried out in the Danish Institute of Agriculture Science in 2000-2001. The experiment concerning growth stage took into consideration three phases of Galium aparine: l, 2 and 3 whorls. The influence of temperature was performed using climate simulator running at three temperatures: 8/2°C, l 6.5/8°C, 24/16°C. The rain was applied using rain simulator 1, 3 and 6 hours after herbicides' treatment. Herbicides: Grody! 75 WG (amidosulfuron 750 g*kg-1), Aurora Super 61,5 WG (mecoprop 600 g=kg' + carfentrazone-ethyl 15 g*kt1), Lintur 70 WG (dicamba 65.9 g=kg', triasulfuron 4.1 g=kg') and Chwastox Trio 540 SL (dicamba 40 g*r1, MCPA 200 g"l', mecoprop 300 g*r') were applied in four doses: full recommended, 1/2, 1/4 and 1/8 of full dose on G. aparine. Grody! 75 WG and Aurora Super 61,5 WG were the most efficient to the youngest plants of G. aparine. Differences in susceptibility among three growth stages (1, 2, 3 whorls) to Grody! 75 WG were higher than to Aurora Super 61,5 WG. Effectiveness of tested herbicides tended to increase as temperature rose. The addition of adjuvant improved activity of herbicide Lintur 70 WG that showed satisfactory weed control even at four time reduced dose independently from temperature. The rain treatment 1, 3 and 6 hours after spraying caused reduction of Aurora Super 61,5 WG activity at 1/4 and 1/8 doses. The half dose gave a good result only when rain was applied 6 hours after treatment. Herbicide Grody! 75 WG was efficient after rain application (1, 3, 6 HAT) only at full dose.
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Authors and Affiliations

Renata Kieloch
Krzysztof Domaradzki
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Abstract

Many performing artists in the interwar period in Poland assumed stage names, which were considered a tool of promoting one’s image, but also served other functions, such as the concealment of identity. Over two hundred such pseudonyms — together with the respective artists’ birth names — have been collected and analysed in the article. Approximately in the case of half of them was the original given name retained, and only the surname underwent a change. The comparison of the assumed names with the real ones shows that many names were shortened, and/or made to sound foreign or exotic. Minority surnames — Jewish/German, Russian, Ukrainian — were frequently made to sound Polish, while the Polish ones were foreignised (to make them look English, Italian, French) or vaguely exoticised.

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Authors and Affiliations

Justyna B. Walkowiak
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Abstract

Research regarding blade design and analysis of flow has been attracting interest for over a century. Meanwhile new concepts and design approaches were created and improved. Advancements in information technologies allowed to introduce computational fluid dynamics and computational flow mechanics. Currently a combination of mentioned methods is used for the design of turbine blades. These methods enabled us to improve flow efficiency and strength of turbine blades. This paper relates to a new type turbine which is in the phase of theoretical analysis, because the working fluid is a mixture of steam and gas generated in a wet combustion chamber. The main aim of this paper is to design and analyze the flow characteristics of the last stage of gas-steam turbine. When creating the spatial model, the atlas of profiles of reaction turbine steps was used. Results of computational fluid dynamics simulations of twisting of the last stage are presented. Blades geometry and the computational mesh are also presented. Velocity vectors, for selected dividing sections that the velocity along the pitch diameter varies greatly. The blade has the shape of its cross-section similar to action type blades near the root and to reaction type blades near the tip. Velocity fields and pressure fields show the flow characteristics of the last stage of gas-steam turbine. The net efficiency of the cycle is equal to 52.61%.
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Authors and Affiliations

Stanisław Jerzy Głuch
1
Paweł Ziółkowski
1
Łukasz Witanowski
2
Janusz Badur
2

  1. Gdansk University of Technology, Faculty of Mechanical Engineering and Ship Building, Narutowicza 11/12, 80-233 Gdansk, Poland
  2. Institute of Fluid Flow Machinery Polish Academy of Sciences, Fiszera 14, 80-231 Gdansk, Poland
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Abstract

The low frequency ripple of the input side current of the single-phase inverter will reduce the efficiency of the power generation system and affect the overall performance of the system. Aiming at this problem, this paper proposes a two-modal modulation method and its MPC multi-loop composite control strategy on the circuit topology of a single-stage boost inverter with a buffer unit. The control strategy achieves the balance of active power on both sides of AC and DC by controlling the stable average value of the buffer capacitor voltage, and provides a current reference for inductance current of the DC input side. At the same time, the MPC controller uses the minimum inductor current error as the cost function to control inductor current to track its reference to achieve low frequency ripple suppression of the input current. In principle, it is expounded that the inverter using the proposed control strategy has better low frequency ripple suppression effect than the multi-loop PI control strategy, and the conclusion is proved by the simulation data. Finally, an experimental device of a single-stage boost inverter using MPC multi-loop composite control strategy is designed and fabricated, and the experimental results show that the proposed research scheme has good low frequency ripple suppression effect and strong adaptability to different types of loads.
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Authors and Affiliations

Haiyang Liu
1
Yiwen Chen
1
Sixu Luo
1
ORCID: ORCID
Jiahui Jiang
2
ORCID: ORCID
Haojun Jian
3

  1. Fujian Key Laboratory of New Energy Generation and Power Conversion, Fuzhou University, China
  2. College of Electrical Engineering, Qingdao University, China
  3. State Grid Fujian Electric Power Co., Ltd. China

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