Modelling of the radio spectrum evolution in the binary pulsar B1259−-63

In this paper we give the first attempt to model the evolution of the spectrum of PSR B1259$-$63 radio emission while the pulsar orbits the companion Be star. As suggested by Kijak et al. (Mon. Not. R. Astron. Soc. 418:L114, 2011a) this binary system can be useful in understanding the origin of the gigahertz-peaked spectrum of pulsars. The model explains, at least qualitatively, the observed alterations of the spectral shape depending on the orbital phases of this pulsar. Thus, our results support the hypothesis that the external factors have a significant impact on the observed radio emission of a pulsar. The model can also contribute to our understanding of the origin of some non-typical spectral shapes(e.g. flat or broken spectra).Comment: 9 pages, 2 tables, 3 figure

Good for the heart, good for the Earth: proposal of a dietary pattern able to optimize cardiovascular disease prevention and mitigate climate change

Background and aims: Human and planetary health are inextricably interconnected through food systems. Food choices account for 50% of all deaths for cardiovascular diseases (CVD) - the leading cause of death in Europe - and food systems generate up to 37% of total greenhouse gas (GHG) emissions. Methods and results: Based on a systematic revision of meta-analyses of prospective studies exploring the association between individual foods/food groups and the incidence of CVD, we identified a dietary pattern able to optimize CVD prevention.. This dietary pattern was compared to the current diet of the European population. The nutritional adequacy of both diets was evaluated according to the European Food Safety Authority (EFSA) recommended nutrient intake for the adult population, and their environmental impact was evaluated in terms of carbon footprint (CF). As compared to the current diet, the desirable diet includes higher intakes of fruit, vegetables, wholegrains, low glycemic index (GI) cereals, nuts, legumes and fish, and lower amounts of beef, butter, high GI cereals or potatoes and sugar. The diet here identified provides appropriate intakes of all nutrients and matches better than the current Europeans' one the EFSA requirements. Furthermore, the CF of the proposed diet is 48.6% lower than that of the current Europeans' diet. Conclusion: The transition toward a dietary pattern designed to optimize CVD prevention would improve the nutritional profile of the habitual diet in Europe and, at the same time, contribute to mitigate climate change by reducing the GHG emissions linked to food consumption almost by half

Spectrum evolution in binary pulsar B1259-63/LS 2883 Be star and gigahertz-peaked spectra

We study the radio spectrum of PSR B1259-63 orbiting around the Be star LS 2883 and show that the shape of the spectrum depends on the orbital phase. At frequencies below 3 GHz PSR B1259-63 flux densities are lower when measured near the periastron passage than those measured far from periastron. We suggest that an interaction of the radio waves with the Be star environment accounts for this effect. While it is quite natural to explain the pulsar eclipse by the presence of an equatorial disk around LS 2883, this disk alone cannot be responsible for the observed spectral evolution of PSR B1259-63 and we, therefore, propose a qualitative model which explains this evolution. We consider two mechanisms that might influence the observed radio emission: free-free absorption and cyclotron resonance. We believe that this binary system can hold the clue to the understanding of gigahertz-peaked spectra of pulsars.Comment: 5 pages, 4 figures, MNRAS Letters, 418, L114-L118 (2011

Nucleic acid-based fluorescent probes and their analytical potential

It is well known that nucleic acids play an essential role in living organisms because they store and transmit genetic information and use that information to direct the synthesis of proteins. However, less is known about the ability of nucleic acids to bind specific ligands and the application of oligonucleotides as molecular probes or biosensors. Oligonucleotide probes are single-stranded nucleic acid fragments that can be tailored to have high specificity and affinity for different targets including nucleic acids, proteins, small molecules, and ions. One can divide oligonucleotide-based probes into two main categories: hybridization probes that are based on the formation of complementary base-pairs, and aptamer probes that exploit selective recognition of nonnucleic acid analytes and may be compared with immunosensors. Design and construction of hybridization and aptamer probes are similar. Typically, oligonucleotide (DNA, RNA) with predefined base sequence and length is modified by covalent attachment of reporter groups (one or more fluorophores in fluorescence-based probes). The fluorescent labels act as transducers that transform biorecognition (hybridization, ligand binding) into a fluorescence signal. Fluorescent labels have several advantages, for example high sensitivity and multiple transduction approaches (fluorescence quenching or enhancement, fluorescence anisotropy, fluorescence lifetime, fluorescence resonance energy transfer (FRET), and excimer-monomer light switching). These multiple signaling options combined with the design flexibility of the recognition element (DNA, RNA, PNA, LNA) and various labeling strategies contribute to development of numerous selective and sensitive bioassays. This review covers fundamentals of the design and engineering of oligonucleotide probes, describes typical construction approaches, and discusses examples of probes used both in hybridization studies and in aptamer-based assays

Hydrochemical flood flow of the Vistula -august 2001

Intense rain in the south em part of the Vistula 's watershed in Ju(v 2001 resulted in floods in many places and in flood water flows on the Vistula and its tributaries. The culmination of the flood reached the Gulf of Gdańsk in the night of 5th August 2001. In the period 4th to 6th August, 10 samples of water were taken, and d1e content of biogenic substances and of other components in these samples was determined. Basing on water flow measurements and on the content of the investigated components, the loads were calculated and compared with mean multi-annual loads for the pen·od 1984- 1998. It was found that the mean biogen load, related to water flow, was exceeded many times. Also the relationships between the analysed components, water flow and variability during the period of investigations were detennined. Obtained results show that there may be a very significant influence of biogens on the condition of the environment and on the dynamics of biocenotic processes of the Gulf of Gdańsk in the period before and after the propagation of flood waters of the Vistula

Walidacja metody oznaczania węgla całkowitego, nieorganicznego i organicznego w wodach morskich

Validation is a process of setting parameters characterizing the proficiency of actions and limitations of a method and an assessment of its usefulness for particular purposes. As a result, it ensures that the analysis process is carried out in a reliable and precise way and gives reliable results. For the validation process marine water was used, as well as the addition of standard solutions. Uncertainty in the results, limit of quantification, precision, repeatability and reproducibility, recovery and accuracy of the method were obtained. The results of the validation of the method for determination of total inorganic and organic carbon in marine waters are discussed in this paper. For this purpose, a Shimadzu analyser TOC-L was used. The discussed method is based on infrared detection NDIR. A halogen scrubber type B was used for determined the compounds. This allowed the analysis time at the stage of the sample preparation to be shortened. It increased the absorption of salt contained in a sample, as a result of which, the dilution stage could be omitted, and the final result is affected by a smaller error. The method of the validation for determination of total inorganic and organic carbon received accreditation of the Polish Centre for Accreditation and joined a wide range of the analyses carried out in the Laboratory of the Department of Environment Protection of the Marine Institute in Gdańsk.Walidacja jest procesem ustalania parametrów charakteryzujących sprawność działania i ograniczeń metody oraz sprawdzeniem jej przydatności do określonych celów. W efekcie można uzyskać pewność, że proces analizy przebiega w sposób rzetelny i precyzyjny oraz daje wiarygodne wyniki. Do procesu walidacji wykorzystano wodę morską, a także tą samą wodę z dodatkami wzorców. Walidacja metody pozwoliła na określenie takich parametrów, jak: niepewność wyników, granica oznaczalności, precyzja, powtarzalność i odtwarzalność, a także odzysk i dokładność metody. W niniejszej pracy omówione zostały wyniki walidacji metod oznaczania węgla całkowitego, nieorganicznego i organicznego w próbkach wody morskiej. W tym celu wykorzystano analizator TOC-L firmy Shimadzu. Omawiana metoda polega na detekcji w podczerwieni NDIR. Do przeprowadzenia badań zastosowano skruber halogenów typu B. Pozwolił on na skrócenie czasu analizy na etapie przygotowania próbki. Zwiększył on pochłanianie soli zawartej w próbce, w wyniku czego można było pominąć etap rozcieńczania, a wynik końcowy obarczony jest mniejszym błędem. Metoda oznaczania węgla całkowitego, nieorganicznego i organicznego uzyskała akredytację Polskiego Centrum Akredytacji i dołączyła do szerokiego grona analiz wykonywanych w Laboratorium Zakładu Ochrony Środowiska Instytutu Morskiego w Gdańsku

Oznaczanie związków ropopochodnych w osadach dennych

The following study was a theoretical base for selection, development and validation of the analytical procedure for determination of petroleum hydrocarbons in bottom sediments to be used in a commercial research laboratory. Crude oil and petroleum products belong to the group of pollutants that are easily accumulated in sediments. The process of accumulation of petroleum substances is due to the large sorption capacity. Having accumulated in sediments, the substances may constitute a secondary source of pollution which, despite being cut-off from the primary sources, may yet cause environmental pollution for a number of years. Recognition of the level of contamination in sediments, and monitoring of changes in the environment require employment of appropriate analytical procedures, which would ensure that the work is less laborious and time-consuming.Niniejsza praca stanowiła podstawę teoretyczną do wyboru i opracowania właściwej procedury analitycznej oznaczania węglowodorów ropopochodnych w osadach dennych do zastosowania w komercyjnym laboratorium badawczym. Ropa naftowa i produkty ropopochodne należą do tych zanieczyszczeń, które mogą gromadzić się w osadach dennych. Proces kumulacji substancji ropopochodnych spowodowany jest dużą pojemnością sorpcyjną. Kumulując się w osadach substancje te mogą stanowić wtórne źródło zanieczyszczeń, które mimo odcięcia źródeł pierwotnych jeszcze długie lata będą przyczyną zanieczyszczenia środowiska. Poznanie stopnia skażenia osadów dennych jak i monitorowanie zmian w środowisku, wymaga posiadania odpowiednich procedur analitycznych, które zapewnią małą czaso- i pracochłonność

Ocena stężeń tributylocyny w próbkach z Portu Gdynia

Tributyltin (TBT) may affect various organisms. TBT has been used in antifouling paints for the protection of ship hulls and hence harbor sediments may contain high concentrations of TBT. This study shows TBT concentrations found in sediments from three basins (No. V, VI, and VIII) of the Port of Gdynia. TBT concentrations ranged from 291 to 1689 ngSn·g-1 d.w. and should be classified as highly contaminated and grossly contaminated [20]. These results indicate that TBT in harbour sediments is an environmental risk that may be emphasized by dredging operations in the region. However, obtained results confirm also the global tendency for depreciating content of TBT in port sediments after the global banning on the use of TBT in 2008.Tributylocyna (TBT) może wpływać negatywnie na różne organizmy. TBT była stosowana jako komponent w farbach przeciwporostowych do ochrony kadłubów statków, dlatego też osady portowe mogą zawierać wysokie stężenia TBT. W pracy przedstawiono ocenę zawartości TBT w osadach z trzech basenów (nr V, VI i VIII) w Porcie Gdynia. Stężenia TBT zawierały się w zakresie od 291 do 1689 ngSn-g-1 s.m. i powinny być klasyfikowane jako wysoce zanieczyszczone i rażąco zanieczyszczone [20]. Wyniki te wskazują, że TBT w osadach portowych stanowi realne ryzyko środowiskowe, które może być zwiększone w wyniku prowadzenia prac pogłębiarskich w porcie. Jednakże, uzyskane wyniki potwierdzają również ogólną tendencję do zmniejszania zawartości TBT w osadach portowych w wyniku wprowadzenia zakazu stosowania TBT w 2008 roku

Walidacja metody oznaczania tributylocyny (TBT) w gruntach i osadach dennych

Tributyltin (TBT) belongs to the group of persistent pollutants harming the marine environment. It is a danger to many aquatic organisms, especially those inhabiting seabed sediments. TBT was used mainly in production of antifouling paints applied on ship’s hulls. Currently, it is prohibited to use most products containing TBT [6; 8; 16]. The objective of this study was to confirm applicability of the method for determining the levels of tributyltin compounds in soils and bottom sediments which remains in accordance with the HELCOM recommendations [11]. In Poland, there is no sufficient data on the levels of TBT concentrations in the Baltic Sea, which is why it is so important to monitor these compounds in the seabed sediments, where they tend to accumulate.Tributylocyna (TBT) zaliczana jest do trwałych zanieczyszczeń środowiska morskiego. Zagraża wielu organizmom wodnym, zwłaszcza bytującym w osadach dennych. TBT wykorzystywana była głównie do produkcji farb przeciwporostowych używanych do malowania kadłubów statków. Obecnie stosowanie większości środków zawierających TBT zostało zabronione [6; 8; 16]. Celem przeprowadzonej walidacji było potwierdzenie możliwości stosowania metody oznaczania zawartości tributylocyny w osadach dennych i gruntach zgodnej z zaleceniami HELCOM [11]. W Polsce brakuje wystarczających danych o poziomach stężeń TBT w Bałtyku, dlatego tak ważne jest monitorowanie tych związków w osadach dennych, w których się kumulują