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Number of results: 58
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Abstract

232 specimens of Notothenia coriiceps neglecta and 578 specimens of Notothenia rossi marmorata were collected in the region of Admiralty Bay during the period from March to December 1977. The age of the fish was determined from scales. Length — weight relationship was calculated for both species. The parameters of the von Bertalanffy equation were calculated for Notothenia coriiceps neglecta, whereas mean lengths for Notothenia rossi marmorata were given according to the particular age groups.
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Abstract

The approach of a unilateral impact of the financial sector on economic growth was invalidated by the last financial crisis which very quickly changed into a global economic crisis. The aim of the study is the analysis of the impact of the financial sector on economic growth in the context of the growing phenomenon of financialization, which was one of the significant reasons of the financial crisis. The study was focused on presenting the growing scale of this phenomenon and analysing the impact of money supply in USD and EUR on world GDP and the GDP of the USA and the Eurozone. The following hypothesis was postulated: the growing process of financialization causes the growth of the USD and EUR supply, influencing changes in the world GDP, the GDP of the USA and the Eurozone. The study confirmed the hypothesis of the relation of the money supply with changes in economic growth. However, influencing economic growth with the money supply causes the purchasing power of business entities to decrease and causes growing debt. Furthermore, it does not contribute to the strength of the real economy. A repair of the current “system“ should not be sought for in constantly increasing macroprudential regulations, but in a return to a country’s interventionism, leading to a change in the priorities of the actions of financial institutions; mainly banks, and the supply of money based on fixed parities (gold, energy).
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Abstract

The aim of the article is to analyse the spread and diffusion of socio-economic development in Poland in 2004-2016, while considering spatial aspects. Using the linear ordering method in the non-pattern version, a synthetic development measure for all municipalities in Poland was built based on a set of 77 features illustrating various socio-economic aspects, reduced to 25 features. For the measure constructed in this way, the convergence of the beta and sigma type has been examined, divided into 3 groups of municipalities (rural, urban and urban-rural), as well as in regional division. Using the methods of spatial econometrics, the occurrence of spatial effects was examined, in particular the attention was paid to the relationship between the processes of spreading development and spatial forms of diffusion of development. The analysis also allowed to determine the strength of local impacts of spatial connections between individual municipalities.
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Abstract

Recent works of the authors, concerning the future of urban regions, are synthesised in the paper. Three methodological paths – focused on exploring and creating the future of urban regions – are the backbone of the presented work. Within the fi rst path, creation of regional future by applying the concept of intellectual and strategic challenges is recommended. Second path introduces a new perspective for the future, based upon vehicles. A new philosophy of urban and regional growth emerges here. Third path is a new approach towards creation of regional specialisations in a contemporary notion of technological and creative economy.
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Abstract

This study was carried out on the background of Sutong Bridge project based on fracture mechanics, aiming at analyzing the growth mechanism of fatigue cracks of a bridge under the load of vehicles. Stress intensity factor (SIF) can be calculated by various methods. Three steel plates with different kinds of cracks were taken as the samples in this study. With the combination of finite element analysis software ABAQUS and the J integral method, SIF values of the samples were calculated. After that, the extended finite element method in the simulation of fatigue crack growth was introduced, and the simulation of crack growth paths under different external loads was analyzed. At last, we took a partial model from the Sutong Bridge and supposed its two dangerous parts already had fine cracks; then simulative vehicle load was added onto the U-rib to predict crack growth paths using the extended finite element method.
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Abstract

The article highlights the issues of the quality of the newly developed residential areas in Stockholm, in the times of one of the most development intense times in the history of the city. The city of Stockholm has a population of ca. one million residents today and is one of the fastest growing cities in Europe. The high increase in population numbers, high birth rate and strong economy have been the main factors contributing to the rapid city growth. The urgent need for new houses has been addressed by Stockholm’s politicians with an ambitious housing programme. The housing shortage together with the city´s booming economy and actively applied planning policies have created challenges for the decision makers and for the city planners. Most of Stockholm´s new residential areas are being planned outside the city centre which requires a revised approach to the character of the planned spaces and to their density. However, the issues of the quality of the currently planned and built areas are being raised more and more often. Not only the architectural quality has been discussed, but also the scale, structure typologies, the quality of the functional and spatial programmes and that of public spaces. A planning model that has been applied in Stockholm for several years is based on a close co-operation between the city´s planning administration bodies and private investors. A critical element of this kind of a planning model is a strong vision for the city´s future development. The city’s planning administration bodies assure an applicable guidance throughout the planning process. Analysis and conclusions presented in the article are based on practice at planning and administration bodies in Stockholm and in the region of Stockholm in the years 2005-2018.
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Abstract

Rare and endemic plant species represent important components of plant biodiversity which require protection to ensure their sustainable conservation. Cerastium banaticum (Rochel) Heuff. is such an endemic and rare species from Romania, for which the genetic variability of two natural populations was studied by SSR markers. Shannon’s information index revealed low levels of genetic diversity in both populations (I = 0.296). As the first attempt in a conservation program a reproducible micropropagation protocol was established starting from seeds, followed by multiplication, rooting, and ex vitro acclimatization. Among the various plant growth regulators tested the highest multiplication coefficient was achieved on a culture medium with 0.5 mg L-1 6-furfurylaminopurine (K) and 1 mg L-1 α-naphthaleneacetic acid (NAA). On this PGRs concentration a number of 26.6 shoots/individual explant with a mean length of 7.9 cm for new generated shoots was registered. The highest number of roots/individual initiated shoot was 2.6 and it was recorded on a culture medium with 0.5 mg L-1 2-isopentyl-adenine (2iP) and 0.1 mg L-1 NAA. The outdoor acclimatization was successfully performed in a specially designed rocky area in the ‘Alexandru Borza’ Botanical Garden, Cluj-Napoca (Romania).
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Abstract

Globally more than 5.2 billion hectares of farming fields are damaged through erosion, salinity and soil deterioration. Many salt stress tolerant bacteria have plant growth promoting (PGP) characteristics that can be used to overcome environmental stresses. Isolation and screening of salt-tolerant endophytes from Salicornia brachiata were achieved through surface sterilization of leaves followed by cultivation on 4% NaCl amended media. Performance of isolates towards indole-3-acetic acid (IAA) production, phosphate solubilization, ACC deaminase activity, ammonia production, siderophore production and stress tolerance were determined. On the basis of the highest plant growth promoting activity, SbCT4 and SbCT7 isolates were tested for plant growth promotion with wheat and maize crops. In the present study, a total of 12 morphologically distinct salt-tolerant endophytic bacteria was cultured. Out of 12 isolates, 42% of salt-tolerant endophytes showed phosphate solubilization, 67% IAA production, 33% ACC-deaminase activity, 92% siderophore production, 41.6% ammonia production and 66% HCN production. A dendrogram, generated on the basis of stress tolerance, showed two clusters, each including five isolates. The bacterial isolates SbCT4 and SbCT7 showed the highest stress tolerance, and stood separately as an independent branch. Bacterial isolates increased wheat shoot and root dry weights by 60–82% and 50–100%, respectively. Similarly, improved results were obtained with maize shoot (27–150%) and root (80–126%) dry weights. For the first time from this plant the bacterial isolates were identified as Paenibacillus polymyxa SbCT4 and Bacillus subtilis SbCT7 based on phenotypic features and 16S rRNA gene sequencing. Paenibacillus polymyxa SbCT4 and B. subtilis SbCT7 significantly improved plant growth compared to non-inoculated trials.
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Abstract

Rice blast is one of the most destructive rice diseases known to cause considerable yield losses globally. Plant growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF) are closely associated with rice plants and improve plant growth and health. To determine how isolated bacteria trigger rice growth, an assessment of phosphate solubilization and auxin production mechanisms was carried out in vitro and in vivo. In this study, the interactions between PGPR and Rhizophagus irregularis were evaluated in wildtype and CYCLOPS mutant plants to provide a sustainable solution against blast disease and reduce the amount of yield loss. Importantly, Bacillus subtilis UTSP40 and Pseudomonas fluorescens UTSP50 exhibited a suppressive effect on AMF colonization which shows the probable existence of a functional competition between AMF and PGPR to dominate the rhizosphere. On the other hand, R. irregularis decreased the biocontrol activity of B. subtilis UTSP40 in wild type, although this reduction was not significant in mutant plants. Results showed that the same defense-related genes were induced in the roots of wild type colonized by B. subtilis UTSP40 and R. irregularis. Therefore, plant cell programs may be shared during root colonization by these two groups of beneficial microorganisms.
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Abstract

The smart city concept is constantly evolving. More and researchers in Poland and also in the whole world deal with this issue. In practice, it is noted that in cities around the world you can find more and more implemented projects referred as smart, in particular in Barcelona, Vienna and Copenhagen and others. According to the classical definition, smart city means introducing solutions based on the latest information technologies to urban spaces in order to improve the quality of life of city residents. Smart city is a city concept in which solutions can solve the most important problems related to the functioning of cities, such as improvements in public transport and goods in cities, counteracting climate change through the use of energy-saving solutions of city lighting, social inclusion (access city) and others. The concept of smart city is based on IT solutions that are constantly modernized and adapted to specific needs of individual cities. By using real-time access to information, they help make more efficient decisions for city users. However, recent approaches highlight the relationship between modern network technologies and the urban community. One can notice the focus of the researchers on the relational approach, which means combining the smart city concept with the participation of residents in the city management process, and in particular making choices and implementing smart projects. In this sense, the smart city idea defines the way of managing a city in which relations between the self-government, IT providers and science as well as the inhabitants of the city are particularly important. Responding to the needs of residents is particularly important as counteracting the tendency to focus smart products and services in richer places and create socalled an innovation hub with the simultaneous periphery of the remaining districts. Criticism of the smart city concept focuses on the problem of the social polarization of cities, in which the technological revolution contributes more to the increase of socio-economic disparities rather than their decreasing. The aim of the article is to answer the question whether the implementation of the smart city concept polarizes the urban community and does it allow the inclusive development of cities?
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Abstract

A mathematical model of a plane, steady state biofilm, with the use of a single substrate kinetics, was proposed. A set of differential equations was solved. In order to analyse the biofilm’s behaviour, a number of simulations were performed. The simulations included varying process parameters such as detachment coefficient and substrate loading. Two detachment models were taken into consideration: one describing the detachment ratio as proportional to the thickness of the biofilm, and the other one proportional to the thickness of the biofilm squared. The results provided information about substrate and live cell distribution in biofilm and the influence of certain parameters on biofilm behaviour.
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Abstract

The ability to grow clonally is generally considered important for plants in Arctic regions but analyses of clonal characteristics are lacking for entire plant communities. To fill this gap, we assessed the clonal growth of 78 plant species in the Petuniabukta region, central Spitsbergen (Svalbard), and analyzed the clonal and other life−history traits in the regional flora and plant communities with respect to environmental gradients. We distinguished five categories of clonal growth organs: perennial main roots produced by non− clonal plants, epigeogenous rhizomes, hypogeogenous rhizomes, bulbils, and stolons. Clonal growth differed among communities of the Petuniabukta region: non−clonal plants prevailed in open, early−successional communities, but clonal plants prevailed in wetlands. While the occurrence of plants with epigeogenous rhizomes was unrelated to stoniness or slope, the occurrence of plants with hypogeogenous rhizomes diminished with increasing stoniness of the substratum. Although the overall proportion of clonal plants in the flora of the Petuniabukta region was comparable to that of central Europe, the flora of the Petuniabukta region had fewer types of clonal growth organs, a slower rate of lateral spread, and a different proportion of the two types of rhizomes.
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Abstract

In this paper, the deviation from eutectic composition in boundary layer for eutectic growth is studied by phase-field method. According to a series of artificial phase diagram, the lamellar eutectic growth of these alloy is simulated during directional solidification. At steady state, average growth velocity of eutectic lamella is equal to the pulling velocity. With the increasing of the liquidus slope of β phase, the average composition in boundary layer would deviate from eutectic composition and the deviation increases. The constitutional undercooling difference between both solid phases caused by the deviation increases with the increasing of the deviation. The β phase would develop a depression under the influence of the deviation.
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Abstract

Steel is a versatile material that has found widespread use because of its mechanical properties, its relatively low cost, and the ease with which it can be used in manufacturing process such as forming, welding and machining. Regarding to mechanical properties are strongly affected by grain size and chemical composition variations. Many industrial developments have been carried out both from the point of view of composition variation and grain size in order to exploit the effect of these variables to improve the mechanical proprieties of steels. It is also evident that grain growth are relevant to the mechanical properties of steels, thus suggesting the necessity of mathematical models able to predict the microstructural evolution after thermo cycles. It is therefore of primary importance to study microstructural changes, such as grain size variations of steels during isothermal treatments through the application of a mathematical model, able in general to describe the grain growth in metals. This paper deals with the grain growth modelling of steels based on the statistical theory of grain growth originally developed by Lücke [1] and here integrated to take into account the Zener drag effect and is therefore focused on the process description for the determination of the kinetics of grain growth curves temperature dependence.
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Abstract

This study examines the causal links between improvements in economic freedom and changes in GDP per capita of new EU members in transition in the period 2000‒2009. The empirical results suggest significant causality running from changes in monetary and fiscal freedom, trade openness, regulation of credit, labour, and business, legal structure and security of property rights, and access to sound money to movements in GDP per capita, especially in less and moderately developed CEE transition countries. Moreover, we find evidence that improvements in economic freedom are one of the main factors stimulating the convergence of these economies towards rich EU members. The evidence of causality in the opposite direction is much weaker.
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Abstract

The aim of this study was to assess the biological effect of the product Jodis Concentrate (JC) on the rabbit ovaries by evaluating the folliculogenesis and expression of oocyte-specific growth differentiation factor 9 (GDF9). The experiment was conducted with 30 female two month old New Zealand rabbits that were the F1 offspring born to mothers differently treated with Jodis concentrate. The control group (n=10), consisted of F1 offspring born to mothers without iodine treatment, and was not supple- mented with JC. The first experimental group (n=10), consisted of F1 offspring born to mothers treated with JC during pregnancy and the suckling period, and was supplemented with JC daily at a dose of 2 ml/L drinking. The second experimental group (n=10), consisted of F1 offspring born to mothers without iodine treatment, and was also supplemented daily with the same dose of JC - 2 ml/L drinking. All groups were fed with total mixed ration for growing rabbits. The trial lasted 48 days. The ovaries were weighed and prepared for histological examination. The GDF9 protein expression in the ovary was determined by immunohistochemical analysis. The addition of JC to the drinking water of female rabbits led to more active development of the ovarian follicles from primordial to tertiary stage in both experimental groups. More intensive GDF9 protein expression in the oocytes and cumulus cells of rabbits, supplemented with JC was observed.
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Abstract

The effects of gamma irradiation on the vernalization requirements, growth and development of winter wheat grown in a rainout shelter were studied during two successive growing seasons. Dry grains of winter wheat cv. Kobra were irradiated with 300 Gy radiation from a cobalt 60 gamma irradiator. Treated and control grains were pregerminated and subjected to vernalization for 0, 42 or 54 days. Morphological parameters of the plants developing from irradiated seeds (M1 generation) and the plants grown from the seeds produced by the irradiated plants (M2 generation) were measured in order to track the studied effects over two generations. Irradiation of dry grains slowed the growth and development of the plants regardless of the temperature treatment. The measured yield structure elements appeared to be lower for irradiated plants, but no clear effect of radiation on vernalization requirements was noted
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Abstract

Some materials-related microstructural problems calculated using the phase-field method are presented. It is well known that the phase field method requires mesh resolution of a diffuse interface. This makes the use of mesh adaptivity essential especially for fast evolving interfaces and other transient problems. Complex problems in 3D are also computationally challenging so that parallel computations are considered necessary. In this paper, a parallel adaptive finite element scheme is proposed. The scheme keeps the level of node and edge for 2D and level of node and face for 3D instead of the complete history of refinements to facilitate derefinement. The information is local and exchange of information is minimized and also less memory is used. The parallel adaptive algorithms that run on distributed memory machines are implemented in the numerical simulation of dendritic growth and capillary-driven flows.
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Abstract

Twinned dendrites in Al-Zn alloy with high Zn content (40% wt.%) were successfully prepared by directional solidification. At different directional solidification rates (1000 and 1500 μm/s), microstructures and growth orientation variations of Al twinned dendrite and non-twinned dendrite were characterized. By using the inverted trapezoidal graphite sleeve at 1000 μm/s, Al twinned dendrite were formed to developed feather crystal structures in longitudinal section. Its primary and secondary twinned dendrite were grew along [110] direction. Moreover the deviation angle between [110] direction of Al twinned dendrite and the heat flow direction was about 27.15°. While not using the inverted trapezoidal graphite sleeve at 1000 and 1500 μm/s, Al dendrite was the non-twinned dendrite and the twinned dendrite was not appeared. The experimental results showed that the higher temperature gradient, a certain pulling rate and convection environment were the formation conditions of twinned dendrites.
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Abstract

A strip yield model implementation by the present authors is applied to predict fatigue crack growth observed in structural steel specimens under various constant and variable amplitude loading conditions. Attention is paid to the model calibration using the constraint factors in view of the dependence of both the crack closure mechanism and the material stress-strain response on the load history. Prediction capabilities of the model are considered in the context of the incompatibility between the crack growth resistance for constant and variable amplitude loading.
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Abstract

This chapter provides a quantitative analysis to identify weak regions that have changed the innovation model. The analysis was carried out at the beginning of the project, in 2015, when only data on GDP per capita for the EU regions was available until 2011. It was designed to identify regions that have changed the innovation model for their in-depth qualitative research, that is to prepare case studies. To indicate the development paths of European regions, a comparative analysis of means was prepared. Innovation models and their change were indicated by clusters analysis. In addition, an econometric analysis of growth factors in the EU regions covering data on GDP per capita in the EU regions in 2014 was carried out in 2017.
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Abstract

Temperature gradient zone melting (TGZM) method was used to obtain bulk Si continuously for the efficient separation and purification of primary Si from the Si-Al alloy in this work. The effects of alloy thickness, temperature gradient and holding time in TGZM purification technology were investigated. Finally, the continuous growth of bulk Si without eutectic inclusions was obtained. The results showed that the growth rate of bulk Si was independent of the liquid zone thickness. When the temperature gradient was changed from 2.48 K/mm to 3.97 K/mm, the growth rate of bulk Si was enhanced from 7.9×10–5 mm/s to 2.47×10–4 mm/s, which was increased by about 3 times. The bulk Si could grow continuously and the growth rate was decreased with the increase of holding time from 1 h to 5 h. Meanwhile, low refining temperature was beneficial to the removal of impurities. With a precipitation temperature of 1460 K and a temperature gradient of 2.48 K/mm, the removal rates of Fe, P and B were 99.8%, 94.0% and 63.6%, respectively.
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