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Number of results: 38
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Abstract

In this paper a cross-shaped isolator consisting of cuboidal magnets and a cylindrical isolator are compared by resonance frequency to volume ratio and shape. Both isolators are capable of obtaining a low resonance frequency, i.e. 0.15 Hz and 0.01 Hz for the cross and cylinder, respectively. The volume of both isolators is comparable, only the shape is different, resulting in a tall structure with a small footprint for the cross and a flat with a large diameter cylindrical structure. A sensitivity analysis shows that due to the large amount of magnets, the cross-shaped isolator is less sensitive to manufacturing tolerances.

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Authors and Affiliations

D.T.E.H. Van Casteren
J.J.H. Paulides
E.A. Lomonova
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Abstract

The problem of transmitting vibrations with audible frequencies by steel springs, constituting the vibration isolation system was considered in this paper. The analytical relationships allowing determining the value of the transmissibility for the springs resonance frequencies responsible for the transmissibility of high frequency vibrations have been derived and checked by means of FEM method. Also the occurrence of the increasing stresses in the springs in the areas between the resonances has been shown. The typical system, i.e. the serial system with rubber cushion, has been analyzed, reducing the transmission of high frequency vibrations by the spring. It has been shown that the transmission is reduced not as a result of differences in the wave impedance of the boundary of both media but due to the increased dispersion of energy in the rubber, and the analytical relationships allowing the evaluation of the effectiveness of this method have been derived.
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Authors and Affiliations

Jerzy Michalczyk
Leszek Majkut
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Abstract

First psychological research at Arctowski station were conducted in 1979. In the nineties the American team under direction of prof. L. Palinkas conducted research in order to determine the patterns of multicultural psychosocial adaptation. The author discusses stress as a result of isolation and extreme conditions.

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Authors and Affiliations

Stanisław Rakusa-Suszczewski
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Abstract

The article presents the research on the reduction of noise and vibrations carried out using screen theory and its implementation in practice. Acoustic screens are divided according to their application and structures. The article deals with the application of screens in practice, gives their theoretical evaluation and analyses influences of their structure and materials. The evaluation of positive and negative acoustic properties of the screens is given. The conclusion is that screen acoustic properties may be improved by including new elements into design of screens, thus increasing their efficiency in reducing noise effect. Theoretical calculations are performed, and the obtained results are analyzed. In conclusion, it is stated that cylindrical, semi-cylindrical or conical elements have to be applied in the screens.

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Authors and Affiliations

Danielius Guzas
Robertas Klimas
Vaclovas Tricys
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Abstract

In this fast-changing environmental condition, the effect of fossil fuel in vehicle is a significant concern. Many sustainable sources are being studied to replace the exhausting fossil fuel in most of the countries. This paper surveys the types of electric vehicle’s energy sources and current scenario of the onroad electric vehicle and its technical challenges. It summarizes the number of state-of-the-art research progresses in bidirectional dcdc converters and its control strategies reported in last two decades. The performance of the various topologies of bidirectional dc-dc converters is also tabulated along with their references. Hence, this work will present a clear view on the development of state-of-the-art topologies in bidirectional dc-dc converters. This review paper will be a guide for the researchers for selecting suitable bidirectional traction dc-dc converters for electric vehicle and it gives the clear picture of this research field.

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Authors and Affiliations

Lavanya Anbazhagan
Jegatheesan Ramiah
Vijayakumar Krishnaswamy
Divya Navamani Jayachandra
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Abstract

The structural concept of the dome dates back to the Pantheon in Rome. It is used as the cover of many churches and mosques all around the world. Light solutions, with a well-visible dome-shaped truss skeleton, are often preferred in modern architecture. Base isolation techniques can be adopted to mitigate the seismic effects. This paper aims to investigate the efficiency of different designs for the truss skeleton. To solve the problem, one has to assign the constraints, the materials and the geometry of the dome, its supporting structure and the isolation devices (number, locations, and type). The screening of the effects of different scheme assumptions on structural behaviour provides a better insight into the problem.
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Authors and Affiliations

Sara Casciati
1
ORCID: ORCID

  1. SIART srl, Pavia, Italy
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Abstract

Rhizoctonia solani was isolated from 91 % of alder and birch seedlings with stem rot symptoms and 2-3% of seeds. Sowing of seeds to substratum infested with R. solani resulted in pre-and postemergence damping off. On leaves and stem parts of alder and birch, inoculated with 3 isolates of R. solani, necrosis spread from 0.22 to 0.52 mm/hr.
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Authors and Affiliations

Leszek B. Orlikowski
Barbara Duda
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Abstract

Phytophthora cinnarnorni dominated among isolates obtained from diseased 9 species of ericaceous plants. Inoculation of leaves or shoot parts by that species resulted in the fast development of necrosis. In greenhouse trials the pathogen caused root and shoot rot within 10-12-week-growth. The source of isolate had significant influence on the development of Phytophthora rot.
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Authors and Affiliations

Leszek B. Orlikowski
Grażyna Szkuta
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Abstract

The technical requirements for the determination of physical parameters of vibration isolating material have not been standardized in Europe and Poland yet, which significantly hinders the ability to compare vibration isolating materials offered on the market. Therefore, there is a need for establishing a norm that could be applied both for the determination of the physico-mechanical properties of elastic vibration isolation elements in rail transport for domestic and foreign producers as well as in their selection for application in a specific vibration isolation system. The paper presents a proposal to standardize the methodology of the estimation of vibration isolation materials physical parameters authorized for use in vibration isolation systems used in rail transport. Methodology for measuring the physico-mechanical parameters of vibration isolating material presented in the paper forms uniform test procedure developed based on a fragmentary norms for flexible materials testing. The use of the proposed research methodology enables the creation of a unified database of elastic materials which parameters will be easy to compare, and choice between them will become easier for designers of vibration isolation systems used in rail transport.

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Authors and Affiliations

Jarosław Bednarz
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Abstract

Phytophthora cambivora was isolated from the bark lesions of two 10- and 15-year-old of analysed alder trees. Additionally, Botrytis cinerea, 3 Fusarium species, Mucor spp., P. alni and Trichoderma spp. were recovered from diseased tissues. Isolates of P. cambivora from six plant species, used for inoculation of alder seedlings and plant parts, cause dthe development of necrosis. Isolate from Chamaecyparis lawsoniana was the weakest pathogen whereas those from Abies alba, Acer pennsylvanicum and Alnus glutinosa were the strongest.

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Authors and Affiliations

Leszek B. Orlikowski
Tomasz Oszako
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Abstract

Phytophthora citricola was isolated from diseased seedlings of European beech and Silver fir taken from the most of surveyed nurseries. Fusarium species, Pythium ultimum and Rhizoctonia solani were also found in diseased plant tissues.Isoates of P. citricola fro mboth plants and additionally from heather and rhododendron colonised leaf blades, needles and stem parts of beech and fir. In greenhouse trials on inoculated 1-year-old seedlings necrosis spread about 2 mm/24 hr on beech stems whereas on fir about 1.5 mm/24 hr.

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Authors and Affiliations

Leszek B. Orlikowski
Barbara Duda
Grażyna Szkuta
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Abstract

Research over a three year period indicated that P. ramorum occurred rarely in Poland on Rhododendron spp., in spite of established monitoring in nurseries, trade stands, forest and water from early spring to late autumn each year. The pathogen was not found in forests on Vaccinium vitisidaea, Calluna vulgaris, Fagus sylvatica and Quercus rubra, proving its limited spread. The species was detected, however, from 2 rivers. P. citricola was isolated from most of surveyed plants. Besides this P. cactorum, P. cinnamomi, P.citrophthora and P. nicotianae var. nicotianae were isolated from diseased plants. Additionally Pestalotia sydowiana, species of Fusarium, Botrytis cinerea and Trichoderma were often found in diseased plant tissues. Laboratory and glasshouse research showed slight differences in colonization of plants by P. ramorum and P. citricola. However, taking into account the range of host plants, and frequency of pathogen occurrence in infected plant material and water, it became clear that P. citricola poses a much greater danger than P. ramorum to the natural environment in Poland.

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Authors and Affiliations

Leszek B. Orlikowski
Tomasz Oszako
Aleksandra Trzewik
Teresa Orlikowska
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Abstract

The paper presents an analogue circuit testing method that engages the analysis of the time response to a non-periodic stimulus specialized for the verification of selected specifications. The decision about the current circuit diagnostic state depends on an amplitude spectrum decomposition of the time response measured during the test. A shape of the test excitation spectrum is optimized with the use of a differential evolution algorithm and it allows for achieving maximum fault coverage and the optimal conditions for fault isolation. Genotypes of the evolutionary system encode the amplitude spectrum of candidates for testing stimuli by means of rectangle frequency windows with amplitudes determined evolutionarily.

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Authors and Affiliations

Tomasz Golonek
Piotr Jantos
Jerzy Rutkowski
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Abstract

Stem canker and black scurf of potato (Solanum tuberosum L.) caused by Rhizoctonia solani Kühn are important and epidemic diseases in potato-growing regions worldwide, including Iran. In this study, 120 isolates were retrieved from infected stem canker from six potato- growing regions in Iran (Isfahan, Ardebil, Fars, Hamedan, Kurdestan and Kerman). Out of these, 30 isolates were selected as representatives for genetic and virulence analysis. The isolates were analyzed by one sequence analyzes of the ITS-rDNA region, random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR), as well as virulence studies. Based on sequence analysis of the ITS-rDNA region, all 30 isolates were assigned to the anastomosis group (AG) and all were assigned to AG-3 PT. Cluster analysis using the unweighted pair group method with the arithmetic averages (UPGMA) method for both RAPD and ISSR markers revealed that they were divided into three main groups, with no correlation to geographical regions of the isolates. Pathogenicity tests showed that all isolates were pathogenic on potato cv. Agria; however, virulence variability was observed among the isolates. The grouping based on RAPD analysis and virulence variability was not correlated.

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Authors and Affiliations

Mehdi Nasr Esfahani
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Abstract

Roman Ingarden’s work is widely taken as promoting a philosophical anthropology in which considerations from philosophy of ecology, that is, ecophilosophy, have no secure place. I think this contention is too hasty, even though Ingarden himself did not undertake reflections on the responsibility of humans for their natural environment. It is true that here and there he was giving explicit expression to his conviction of the unimportance of biological origins of humans, and was putting a strong emphasis on culture and other intentional creatures of humanity. In my paper I have tried to trace and describe Ingardenian understanding of humans in relation to their environment, and especially to nature. I have made an attempt to show how free human actions are possible, which in turn enforces on humans some responsibility for their actions, including those that impinge upon the nature around them.
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Authors and Affiliations

Adriana Schetz
1
ORCID: ORCID

  1. Uniwersytet Szczeciński, Instytut Filozofii i Kognitywistyki, ul. Krakowska 71–79, 71-017 Szczecin
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Abstract

In the text On Responsibility and Its Ontic Foundations Roman Ingarden stated that responsibility for an act requires the existence of a specific structure of objective and subjective realities, which presuppose the possibility of free choice, the existence of the past, non‑relatively understood values, and personal identity. However, Ingarden’s proposal, which includes ideas such as ‘relatively isolated systems’ or the ‘center of self’ as a condition of the ownership of action, results in insoluble theoretical difficulties. An important cause of this situation is the fact that the whole structure of the argument suggests reflection on the broadly understood issue of responsibility, while the actual intention of the text is narrower. The recurring theme in Ingarden’s A Little Book on Man is the question of inner dignity and the building up of a moral character by an individual, who in the moment of life’s predicament is able to make the right choice. The ontical foundations that Ingarden is looking for in the text On Responsibility and Its Ontic Foundations do not concern the general area of responsibility, but try to justify philosophically the belief in the project of building moral character.
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Authors and Affiliations

Anna Dziedzic
1

  1. Uniwersytet Warszawski, Wydział Filozofii, ul. Krakowskie Przedmieście 3, 00-927 Warszawa
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Abstract

The aim of this paper is defined in the two title questions related to Roman Ingarden’s research: (1) What constitutes the specificity and uniqueness of human cognitive system? (2) Is Roman Ingarden’s answer defensible in the light of today’s naturalistic tendencies? In response to the first question, the multidimensional structure of human being is indicated, thanks to which man has access to the sphere of values. In the axiological and ontological aspect the power of man to create new realities is emphasized. In the epistemological and ontological aspect three dimensions of this structure are shown, which are correlated, complex and relatively isolated systems of body, soul and consciousness. Next, in response to the second question, Ingarden’s nonreductive approach is discussed against the background of information processes and the issue of self-knowledge. However, his strong ontological assumptions are shown as well. In conclusion, the author emphasizes that Ingarden’s main research strategy remains consistently grounded in ontology (and in this sense it is anti‑naturalistic), but in some aspects it is compatible with today’s naturalist approaches favored in neurocognitive studies.
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Authors and Affiliations

Urszula Żegleń
1
ORCID: ORCID

  1. Uniwersytet Mikołaja Kopernika w Toruniu, Instytut Badań Informacji i Komunikacji, ul. Bojarskiego 1, 87-100 Toruń
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Abstract

RNA extraction involves several main stages, regardless of the method of extraction: homogenization, effective denaturation of proteins from RNA, inactivation of ribonuclease and removal of any DNA, protein, and some residual contamination. Isolation of undamaged intact RNA is challenging when the related tissue contains high levels of polysaccharides and phenols. Several efforts have been made towards the comparison and optimization of extraction and purification methods for RNA from plant tissues. This is dictated by the necessity of obtaining RNA of a good quality and in a sufficient quantity for further molecular analyzes. Plant storage organs (such as bulbs or seeds) rich in polysaccharide and polyphenolic compounds present distinct challenges for total RNA isolation. Such components, considered in this case as contamination, may bind and co-precipitate with nucleic acids and negatively affect later assays. Since standard routine protocols yield unacceptable results in bulbs, we have designed a new method for RNA extraction. We used two modified procedures (based on CTAB and sarkosyl reagents) of RNA extraction from so called “difficult plant material” and compared them to a popular RNA isolation base on the column isolation kit and TriPure reagent. Our modified protocols dealt with problems of both RNA degradation and low yield caused by co-purification with polysaccharides present in plant bulbs. In this study we have shown that improvement of the CTAB and sarkosyl method with a lyophilization step of plant tissues leads to isolation of high quality RNA from difficult material like storage organs of bulbous plants. The main changes in the procedure compared to the previously described methods concerned the different order of lithium chloride and sodium acetate addition, lithium chloride concentration increase and modification of centrifugation conditions. Gel electrophoresis and spectrophotometer analysis confirmed the high quality and integrity of the obtained RNA. The modified procedures allowed for obtaining a satisfying amount of RNA concentration in the range from 280 to 950 ng/μl depending on the plant species. Thus, the demonstrated RNA isolation methods are efficient and can be used for plant material rich in polysaccharides, such as bulbs.

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Authors and Affiliations

Maria Duszyn
Brygida Świeżawska
Mateusz Kwiatkowski
Krzysztof Jaworski
Adriana Szmidt-Jaworska
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Abstract

Microvibrations are mechanical oscillations caused by components such as the reaction wheels of an attitude control system of a spacecraft. These microvibrations are transferred through the spacecraft structure onto important instruments (e.g., optical instruments), causing those to produce diminished results (e.g., reduced image quality, imprecise geolocation etc.). At the present state, microvibrations in spacecraft cannot be actively controlled because their very high frequencies of up to 1000 Hz are above the control bandwidth a current attitude control system can provide. However, being able to reduce the effects of microvibrations on a space mission is becoming increasingly more critical as the envelope of future optical satellite missions expands. Furthermore, the advancements made in the performance of small satellites as well as the growing interest in laser and quantum communication call for a cost-efficient solution for managing microvibrations. This paper describes how cheap MEMS-based measurement systems have already proven that they are a potential solution. Showing high sensitivity and low-noise performance while allowing fast and easy prototyping.
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Bibliography

[1] ECSS. Micro-vibrations, Space Engineering: Spacecraft Mechanical Loads Analysis Handbook, ECSS-E-HB-32-26A, 2013.
[2] A. Bronowicki. Forensic investigation of reaction wheel nutation on isolator. In 49th AIAA Structures, Structural Dynamics, and Materials Conference, Schaumburg, IL, USA, 7-10 April 2008. doi: 10.2514/6.2008-1953
[3] T. Runte, Z. Perez, and M. Baro. Microvibration engineering – a key to high-performance space missions. In 70th International Astronautical Congress, Washington, D.C., USA, 21-25 Oct. 2019.
[4] C.J. Dennehy. A survey of reaction wheel disturbance modeling approaches for spacecraft line-of-sight jitter performance analysis. In Proceeding of 18 European Space Mechanisms and Tribology Symposium, Munich, Germany, 18-20 Sept. 2019.
[5] H. Heimel. Spacewheel microvibration-sources, appearance, countermeasures. In Proceedings of the 8th International ESA Conference on Guidance & Navigation Control Systems, Karlove Vary, Czech Republic, 5-10 June 2011.
[6] C. Dennehy and O.S. Alvarez-Salazar. Spacecraft micro-vibration: A survey of problems, experiences, potential solutions, and some lessons learned. Technical report, 2018.
[7] M. Manso and M. Bezzeghoud. On-site sensor noise evaluation and detectability in low cost accelerometers. In Proceedings of the 10th International Conference on Sensor Networks – SENSORNETS, pages 100–106. [Online], 9-10 Febr. 2021. doi: 10.5220/0010319001000106.
[8] G. Heinzel, A. Rudiger, and R. Schilling. Spectrum and spectral density estimation by the Discrete Fourier Transform (DFT), including a comprehensive list of window functions and some new flat-top windows. Technical report, 2002.
[9] A. Wiebe. Entwicklung eines Teststandes zur Messung von Mikrovibrationen inklusive Auslegung eines Datenaufnahmesystems. Technical report, 2021.
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Authors and Affiliations

Antonio Garcia
1
Tim Gust
1
Enes Basata
1
Tim Gersting
1
Michal Deka
1
Sven Thiele
1
Mohammad Salah
1
Matias Bestard Koerner
2
Torben Runte
3
Miguel Gonzalez
3

  1. City University of Applied Sciences Bremen, Institute of Aerospace Technologies, Bremen, Germany
  2. German Aerospace Center – DLR, Institute of Space Systems. Guidance, Navigation and Control Systems. Bremen, Germany
  3. OHB System AG, Bremen, Germany
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Abstract

Plastics have become indispensable in everyday life due to their properties. For this reason, the accumulation of polymer waste in the natural environment is becoming a serious global problem. The aim of the research was to isolate microorganisms capable of biodegrading plastics. The studies focused on the biodegradation of low-density polyethylene as the most common polymer. Seven and five bacterial strains were isolated from the landfill and compost, respectively. The morphological and biochemical characteristics of the isolates were determined. These isolates were able to survive in an environment where the only carbon source was LDPE, but no increase in biomass was obtained. However, analysis of the spectra obtained by the ATR-FTIR method showed the formation of chemical changes on the polymer surface. Bacterial biofilm formation was visualized by scanning electron microscopy. The toxicity of plastic biodegradation products in a liquid environment was tested and their safety for plants was confirmed. However, these biodegradation products have acute lethal toxicity for the Daphnia magna.
LDPE films were pre-treated with H 2O 2, HNO 3, or heat. The biodegradation of HNO 3-treated LDPE by isolated bacteria was the most significant. The weight loss was approximately 8%, and 6%, for landfill and compost-isolated bacterial strains, respectively.
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Authors and Affiliations

Elżbieta Szczyrba
1
ORCID: ORCID
Tetiana Pokynbroda
2
ORCID: ORCID
Nataliia Koretska
2
ORCID: ORCID
Agnieszka Gąszczak
1
ORCID: ORCID

  1. Instytut Inżynierii Chemicznej Polskiej Akademii Nauk, ul. Bałtycka 5, 44-100 Gliwice, Poland
  2. Department of Physical Chemistry of Fossil Fuels of the Institute of Physical-Organic Chemistry and Coal Chemistry named after L.M. Lytvynenko of the National Academy of Sciences of Ukraine, Naukova str, 79060, Lviv, Ukraine
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Abstract

Common alder (Alnus glutinosa) decline has been observed in most of European countries since 1993. In Poland decline of alder trees has been observed during the last 6 years. Alder Phytophthora was recorded, however, only from one sampling area in the middle of the country. Species of Armillaria, Fusarium, Mucor, Penicillium and Trichoderma were also isolated from diseased trees. Inoculation of alder stem pans, leaves and seedlings with Phytophthora isolates resulted in the development and spread of necrosis. Studies will be continued in the nearest years.
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Authors and Affiliations

Leszek B. Orlikowski
Tomasz Oszako
Grażyna Szkuta
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Abstract

Phoma exigua var. inoxydabilis var. nov. predominated among fungal isolates obtained from diseased stem runners and leaves of periwinkle ( Vinca minor). The growth of the fungus was observed at temperature ranges from 7.5 to 30°C with optimum at 25°C. Abundant formation of picnidia was noticed mainly on malt extract agar at temp. I 5-25°C. On potato-dextrose agar picnidia were observed 3-5 days later. On inoculated leaves of periwinkle, development of necrosis was observed at temperature I0-25°C with optimum 20°C. On field grown periwinkle the first necrosis on the base of stem runners was observed 2 weeks after inoculation and during the next I O weeks discoloration of tissues occurred on about 1/2 of their length.
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Authors and Affiliations

Leszek B. Orlikowski
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Abstract

A comprehensive characterization of four selected fault distinguishability methods is presented herein. All considered methods are derived from structural residual approaches referring to model-based diagnostics. In particular, these methods are based on a binary diagnostic matrix, fault isolation system, sequences of symptoms, and their combinations. Fault distinguishability issues are discussed based on an example of four pressure vessel system. Substantial benefits are shown in fault distinguishability figures obtained by utilising extended knowledge regarding fault-symptom relation. Finally, the values of three fault distinguishability metrics are calculated for each method. For the case study, the highest score is achieved using the multivalued fault isolation method combined with a diagnosis utilising information regarding the antecedence of symptoms.

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Authors and Affiliations

J.M. Kościelny
M. Bartyś
K. Rostek
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Abstract

This project aimed to isolate and characterize volcanic soil Actinobacteria from Deception Island, Antarctic. A total of twenty−four Actinobacteria strains were isolated using four different isolation media (Starch casein agar, R2 agar, Actinomycete isolation agar, Streptomyces agar) and characterized basing on 16S rRNA gene sequences. Tests for secondary metabolites were performed using well diffusion method to detect antimicrobial activities against eight different pathogens, namely Staphyloccocus aureus ATCC 33591, Bacillus megaterium , Enterobacter cloacae , Klebsiella oxytoca , S. enterica serotype Enteritidis, S. enterica serotype Paratyphi ATCC 9150, S. enterica serotype Typhimurium ATCC 14028 and Vibrio cholerae . Antimicrobial properties were detected against Salmonella paratyphi A and Salmonella typhimurium at the concentration of 0.3092±0.08 g/ml. The bioactive strains were identified as Gordonia terrae , Leifsonia soli and Terrabacter lapilli. Results from this study showed that the soil of Deception Island is likely a good source of isolation for Actinobacteria. The volcanic soil Actinobacteria are potentially rich source for discovery of antimicrobial compounds.
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Authors and Affiliations

Yoke−Kqueen Cheah
Learn−Han Lee
Cheng−Yun Catherine Chieng
Vui−Ling Clemente Michael Wong

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