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Effect of sodium sulphate salinity for production of docosahexaenoic acid (DHA) by Thraustochytrids aureum RAK-21

Abstract

Background: The demand for DHAs in human nutrition, fish feeds, and pharmaceutical applications is rapidly growing and it will become inadequate for supplying the expanding market. In order to meet the expected rise in the demand and to circumvent the drawbacks of the fish oil, it is important to develop new sources of this important nutrient, which leads the need for alternative production processes for DHA.

Objectives: The effect of sodium sulphate salinity on Docasahexaenoic acid (DHA) synthesis in Thraustochytrids aureum RAK-21 was studied with media constitution as well as conditions in batch fermentation.

Methods: Thraustochytrids aureum RAK-21 resuspended cell system using shake ask fermentation was deployed to study the production of DHA synthesis. The effects of key parameters such as salinity, different types of carbon sources, nitrogen sources, temperature, and pH on DHA production were also investigated.

Results: The sodium sulphate salinity was much influenced in growth as well as DHA production as compared with sodium chloride in medium. The results showed that sodium sulphate (30g/L) in the presence of peptone (15g/L) and sucrose (20g/L) were the most effective medium for higher DHA production at pH 7 and 35° C.

Conclusions: The present study reveals that sulphate ions are an important element for effective DHA synthesis along with sodium ions. It may influence the primary or co-metabolism pathways of DHA and other Long-chain polyunsaturated fatty acid (LCPUFA) production.

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Methods of Reliability Index Determination Concerning Municipal Water Quality

References Barański B., Szymczak W., i inni: Podstawy metod oceny ryzyka zdrowotnego. Wydawnictwo Instytutu Medycyny Pracy. Łódź, 1995 r. Brandowski A.: Koncepcja nauki o bezpieczeństwie. Zagadnienia Eks-ploatacji Maszyn. Wydawnictwo. PAN, z. 3(95), 1993, s. 261-279. Rak J.: Niezawodność systemu uzdatniania wód powierzchniowych. Zeszyty Naukowe Politechniki Rzeszowskiej, seria Budownictwo i Inżynieria Środowiska. z. 20. Oficyna Wydawnicza Politechniki Rzeszowskiej, Rzeszów

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Waterborne Phytophthora Species Occurrence and Diversity in the Valley of the Rák Brook

Abstract

This paper reports on a two-year monitoring of Phytophthora species occurring in the catchment area of the Rák Brook near Sopron. P. gonapodyides, P. lacustris, P. plurivora and P. pseudosyringae were found in the course of surveys completed in the vegetation period of 2011 and 2012. Diversity profiles and cluster analysis were calculated in order to compare the Phytophthora communities detected at different sites and times. Seasonal differences were observed in the species compositions. Temperature data and basic hydrological parameters were found to determine the presence or absence of waterborne Phytophthora species in the catchment area of the Rák Brook. Pathogenicity of the Phytophthora species discovered was confirmed and evaluated against sessile oak seedlings.

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The Possible Use of the FMEA Method to Ensure Health Safety of Municipal Water

.) MacGillivray, B. H., Hamilton, P. D., Strutt, J. E., and Pollard, S. J. T.: Risk analysis strategies in the water utility sector: an inventory of applications for better and more credible decision making , Critical Reviews in Environmental Science and Technology, 36(2): 85-139, 2006 Rak J., Tchórzewska-Cieślak B.: Metody analizy i oceny ryzyka w systemie zaopatrzenia w wodę. Oficyna Wydawnicza Politechniki Rzeszowskiej. Rzeszów 2005. Rak J., Tchórzewska-Cieślak B., Kalda G.: Metoda analizy ryzyka przyczyn i skutków

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Shift Work and Cancer: State of Science and Practical Consequences

Shift Work and Cancer: State of Science and Practical Consequences

In 2007, an expert Working Group convened by the IARC Monographs Programme concluded that shift work that involves circadian disruption is probably carcinogenic to humans (Group 2A). We scrutinised the epidemiological basis for this conclusion, with a focus on, but not limited to, breast and prostate cancers. We further considered practical consequences for shift workers in our industry against the background of new findings.

We carried out a literature search including the epidemiological studies cited by IARC and newer available literature on shift work and cancer.

Since the IARC assessment, eleven new studies have emerged, ten of which have already been published, with inconclusive results. Heterogeneity of exposure metrics and study outcomes and emphasis on positive but non-significant results make it difficult to draw general conclusions. Also, several reviews and commentaries, which have been published meanwhile, came to equivocal results. Published evidence is widely seen as suggestive but inconclusive for an adverse association between night work and breast cancer, and limited and inconsistent for cancers at other sites and all cancers combined.

At this point in time it can not be ruled out that shift work including night work may increase the risk for some cancers in those who perform it. However, shift schedules can be organised in ways that minimise the associated health risks, and the risks may be further reduced through the implementation of structured and sustained health promotion programs specifically tailored to the needs of shift workers.

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New Mississippian trilobite association from the Brno vicinity and its significance (Moravian Karst, Czech Republic)

., Leichmann J., Bábek O. & Melichar R. 2003: Brunovistulian Terrane (Central Europe) and Istanbul Zone (NW Turkey): Late Proterozoic and Paleozoic tectonostratigraphic development and paleogeography. Geol. Carpathica 54, 139-152. Kalvoda J., Bábek O., Fatka O., Leichmann J., Melichar R. & Špaček P. 2008: Brunovistulian terrane (Bohemian Massif, Central Europe) from late Proterozoic to late Paleozoic: a review. Int. J. Earth Sci. 97, 497-518. Kalvoda J., Devuyst F. X., Bábek O., Dvořák L., Rak Š. & Rez J. 2010: High

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Water surface topology of supercritical junction flow

models – the significance of the Weber number. J. Hydrol., 35, 2, 199–212. Pfister, M., Chanson, H., 2014. Two-phase air-water flows: Scale effects in physical modelling. J. Hydrodyn. Ser. B, 26, 2, 291–298. Pfister, M., Gisonni, C., 2014. Head losses in junction manholes for free surface flows in circular conduits. J. Hydraul. Eng., 140, 9, 1–6. Pinto Coelho, M.M., 2015. Experimental determination of free surface levels at open-channel junction. J. Hydraul. Res., 53, 3, 394–399. Rak, G., 2017. Topološka struktura vodne gladine na sotočju pri

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Method of Analysis and Assessment of ICT System Safety in a Water Company

. 4. Liderman K.: Analiza ryzyka dla potrzeb bezpieczeństwa teleinformatycznego. Biuletyn Instytutu Automatyki i Robotyki, 16/2001. 5. Liderman K.: Bezpieczeństwo teleinformatyczne. Wydawnictwo Instytutu Automatyki i Robotyki Wojskowej Akademii Technicznej, Warszawa 2001. 6. Piegdoń I., Tchórzewska-Cieślak B.: Methods of visualizing the risk of lack of water supply. Safety and Reliability: Methodology and Applications - Proceedings of the European Safety and Reliability Conference, ESREL 2014. 7. Rak J.: Podstawy bezpieczeństwa systemów

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Bayesian Inference in the Analysis of the Failure Risk of the Water Supply Network

. Grabski F., Jaźwiński J.: Identyfikacja stanu obiektu technicznego w oparciu o klasyfikację bayesowską. Mat. VII Konferencji Naukowej „Bezpieczeństwo systemów”, Kościelisko’98. Wydawnictwo Instytutu Technicznego Wojsk Lotniczych, Warszawa 1998. 5. Kwietniewski M.: Reliability modeling of Water Distribution System (WDS) for Operation and Maintenance Needs. Archives of Hydro-Engineering and Environmental Mechanics, Monografie Instytutu Budownictwa Wodnego PAN, 51(1), 2004. 6. Kwietniewski M., Rak J.: Niezawodność infrastruktury wodociągowej i kanalizacyjnej w

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Technological Innovation in the Aspect of Safety in the Process of Heat Supply

heating systems: A review of modelling and optimization . Solar Energy, 136, 49–64. DOI: 10.1016/j.solener.2016.06.054. Rak, A., 2016. Narzędzia informatyczne do zarządzania i optymalizacji pracy systemu ciepłowniczego. Zeszyty Naukowe UE w Katowicach, 308, 115-127. Rak, A., 2017. Selected aspects of hydraulic issues in heating systems. Production Engineering Archives, 14, 27-32. Rak, A., 2018. Selected aspects of technological innovations management in district heating companies. MATEC Web of Conferences, 183. DOI: 10.1051/matecconf/201818304003

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