Analysis of the possibilities in railways shape assessing using GNSS mobile measurements

In recent years, a dynamic development of satellite positioning techniques using both static and mobile GNSS coordinates register mode can be observed. In addition, still developing Real-time GNSS Networks, post-processing algorithms and another measurement signal analysis algorithms, make the satellite measurements increasingly used in railway industry sector. In the article the possibilities which follows from the mobile satellite measurements in railway engineering are briefly presented. In the years 2009-2015, the authors conducted a series of field investigations on operated railway lines. The obtained results of these measurements led to the development of a number of algorithms that increase the range of applicability of GNSS measurements. The analysis of obtained results also showed how the accuracy of the measurements have increased since 2009. The achieved accuracy has been increased due to a development of GNSS positioning systems as well as improvement of the measurement methodology, i.e. configurations of satellite receivers and layouts of their placement on a mobile measuring platform. It was also found that the development of data analysis algorithms contributed to the increase in the obtained accuracy in assessment of a railway track axis shape. The authors indicate the possibilities of applying GNSS techniques at various stages of construction and operation of railways. According to the authors, the most important advantage of both the presented measurement technique and computational methodology is the ability to effectively and relatively low-cost data acquisition regarding the existing state of the railway line. These data can be successfully used to design changes to the geometry of railway lines, and therefore satellite positioning has enormous application potential in the process of modernization of operated railway lines

Retrotransposon-based genetic variation of Poa annua populations from contrasting climate conditions

Background Poa annua L. is an example of a plant characterized by abundant, worldwide distribution from polar to equatorial regions. Due to its high plasticity and extraordinary expansiveness, P. annua is considered an invasive species capable of occupying and surviving in a wide range of habitats including pioneer zones, areas intensively transformed by human activities, remote subarctic meadows and even the Antarctic Peninsula region. Methods In the present study, we evaluated the utility of inter-primer binding site (iPBS) markers for assessing the genetic variation of P. annua populations representing contrasting environments from the worldwide range of this species. The electrophoretic patterns of polymerase chain reaction products obtained for each individual were used to estimate the genetic diversity and differentiation between populations. Results iPBS genotyping revealed a pattern of genetic variation differentiating the six studied P. annua populations characterized by their different climatic conditions. According to the analysis of molecular variance, the greatest genetic variation was recorded among populations, whereas 41.75% was observed between individuals within populations. The results of principal coordinates analysis (PCoA) and model-based clustering analysis showed a clear subdivision of analyzed populations. According to PCoA, populations from Siberia and the Kola Peninsula were the most different from each other and showed the lowest genetic variability. The application of STRUCTURE software confirmed the unique character of the population from the Kola Peninsula. Discussion The lowest variability of the Siberia population suggested that it was subjected to genetic drift. However, although demographic expansion was indicated by negative values of Fu’s FS statistic and analysis of mismatch distribution, it was not followed by significant traces of a bottleneck or a founder effect. For the Antarctic population, the observed level of genetic variation was surprisingly high, despite the observed significant traces of bottleneck/founder effect following demographic expansion, and was similar to that observed in populations from Poland and the Balkans. For the Antarctic population, the multiple introduction events from different sources are considered to be responsible for such an observation. Moreover, the results of STRUCTURE and PCoA showed that the P. annua from Antarctica has the highest genetic similarity to populations from Europe. Conclusions The observed polymorphism should be considered as a consequence of the joint influence of external abiotic stress and the selection process. Environmental changes, due to their ability to induce transposon activation, lead to the acceleration of evolutionary processes through the production of genetic variability

Rapid environmental changes in the western antarctic peninsula region due to climate change and human activity

The Antarctic and the Southern Ocean are a critically important part of the Earth system. The climatic, physical, and biological properties of this region are closely linked to other parts of the global environment. 200 years of direct human impact, recent climate amelioration and changes in the main sources and circulation of biogenic compounds as well as accumulation of industrial contaminants have significantly affected the whole ecosystem. Particularly sensitive is the region of the Western Antarctic Peninsula, which is considered to be one of the hot spots of the Earth. In this paper, we review recent literature and compare it with historical data to estimate and predict the consequences of this process. The Antarctic ecosystems can no longer be regarded as pristine. Global as well as local human influence has transgressed the barriers isolating that continent from the rest of the World, causing previously observed changes to accelerate

Energy efficiency in the polish residential building stock: A literature review

peer reviewedThe Polish energy market heavily relies on coal. Pressured by the European Union, the Polish government has recently decided to accelerate coal phase-out and to gradually shut down all coal mines by 2049. In that context, it is necessary to assess the Polish energy market's state regarding energy efficiency, especially in the building stock. This paper aims to provide an overview of the current state of energy efficiency of residential buildings in Poland and insights into its future trends. A literature review was conducted, accompanied by focus group discussions with Polish building energy efficiency experts. The Polish energy sector is under a remarkable transformation that may be going too fast. A large gap between expectations, practices, and requirements can be observed. Raising awareness and capacity building in the energy efficiency sector, and a set of accessible guidelines should be developed so that the transformation is implemented correctly. A SWOT analysis results define the key opportunities and threats that are critical to meet net-zero emissions goals. The paper provides findings and insights on the 2020 targets status quo and raises awareness among stakeholders and fills a knowledge gap regarding energy efficiency in the Polish residential building stock.Zero Energy and Low Carbon Buildings in Belgium & Polan

The effects of methanesulfonic acid on seed germination and morphophysiological changes in the seedlings of two Colobanthus species

The effect of methanesulfonic acid (MSA) on the morphophysiology and biochemistry of the subantarctic species Colobanthus apetalus and the Antarctic species Colobanthus quitensis was examined. We evaluated the effects of various concentrations of MSA on the germination capacity and germination rate of seeds, seedling growth, chlorophyll fluorescence in cotyledons, and the proline content of seedlings under laboratory conditions at temperatures of 20°C (day) and 10°C (night) with a 12/12 h photoperiod. The examined C. apetalus seeds were grown in a greenhouse, and C. quitensis seeds were harvested in Antarctica and grown in a greenhouse (Olsztyn, Poland). The seeds of C. apetalus were characterized by the highest germination capacity and the highest germination rate, whereas C. quitensis seedlings were characterized by the most favorable growth and development. Only the highest concentrations of MSA decreased the intensity of chlorophyll fluorescence in the cotyledons of both Colobanthus species. The proline content of C. apetalus and C. quitensis seedlings increased significantly after MSA treatments. The results of this study clearly indicated that Colobanthus quitensis is more resistant to chemical stress induced by MSA. This is a first study to investigate the influence of MSA on the morphophysiology and biochemistry of higher plants

Range‑wide pattern of genetic variation in Colobanthus quitensis

There is only one species representing Magnoliopsida which is considered as native to the Antarctic, i.e., Antarctic pearlwort (Colobanthus quitensis). Although it was intensively studied toward the morphophysiological adaptation to extreme environmental conditions of that area, there is still a lack of sufficient data on its genetic variability. Nine C. quitensis populations from Chile and the Maritime Antarctic were sampled to estimate the pattern of genetic variation in relation to the geographic distribution of analyzed populations and postglacial history of the species. The retrotransposon-based DNA marker system used in our studies appeared to be effective in revealing genetic polymorphism between individuals and genetic differentiation among populations. Although the level of polymorphism was low (9.57%), the Analysis of Molecular Variance showed that overall population differentiation was high (FST = 0.6241) and revealed significant differentiation between the Northern and Southern Group of populations as well as the population from Conguillio Park. The observed genetic subdivision of C. quitensis populations was confirmed by Bayesian clustering and results of Principal Coordinates Analysis. The Southern Group of populations was characterized by generally higher genetic diversity, which was expressed by the values of the effective number of alleles, expected heterozygosity and by the distribution of private alleles. Our results suggest that the species may have survived the Last Glacial Maximum in refugia located both on the South American continent and in geographically isolated islands of the Maritime Antarctic, i.e., they support the concept of the multiregional origin of C. quitensis in Antarctica

Application of Least Squares with Conditional Equations Method for Railway Track Inventory Using GNSS Observations

Satellite geodetic networks are commonly used in surveying tasks, but they can also be used in mobile surveys. Mobile satellite surveys can be used for trackage inventory, diagnostics and design. The combination of modern technological solutions with the adaptation of research methods known in other fields of science offers an opportunity to acquire highly accurate solutions for railway track inventory. This article presents the effects of work carried out using a mobile surveying platform on which Global Navigation Satellite System (GNSS) receivers were mounted. The satellite observations (surveys) obtained were aligned using one of the methods known from classical land surveying. The records obtained during the surveying campaign on a 246th km railway track section were subjected to alignment. This article provides a description of the surveying campaign necessary to obtain measurement data and a theoretical description of the method employed to align observation results as well as their visualisation. Document type: Articl