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Number of results: 32
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Abstract

Pulse electrochemical machining (PECM) provides an economical and e.ective method for machining high strength, heat-resistantmaterials into complex shapes such as turbine blades, die, molds and micro cavities. Pulse Electrochemical Machining involves the application of a voltage pulse at high current density in the anodic dissolution process. Small interelectrode gap, low electrolyte .ow rate, gap state recovery during the pulse o.-times lead to improved machining accuracy and surface .nish when compared with ECM using continuous current. This paper presents a mathematical model for PECM and employs this model in a computer simulation of the PECM process for determination of the thermal limitation and energy consumption in PECM. The experimental results and discussion of the characteristics PECM are presented.
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Abstract

Selected Legal Regulations and Cultural Aspects of Urban Development. Nowadays, the issue of urban development belongs to key elements of development in general. Urban development is a multifaceted phenomenon (covering economic, social, administrative, promotional, ecological and a number of other aspects). They are too numerous to discuss them in one short article. For this reason this paper is dedicated only to the phenomena regulated by law: physical planning, suburbanization (initially called urban sprawl), monument conservation and – additionally – culture (as a factor influencing the legal regulations). The key hypothesis is that developers are not the only ones to blame for the way the country looks. This hypothesis has generally been corroborated.
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Abstract

According to the Grant Map of the Ministry of Development (MoD) as of March-April 2017, there were 1716 urban regeneration (revitalization) projects implemented in Poland between 2007-2013. Data from 11 voivodeships (out of 16 regions NUTS 2 in Poland) and 977 projects was sufficient to provide a representative sample (56,9% of projects presented in the Grant Map). The main methods used in the article included observation and review of MoD statistical data and literature on the subject. As observed by the author, between 2007-2013 the definition of urban regeneration (revitalization) was only mentioned in one of the footnotes to the housing guidelines, which was a poor legal basis for the regional managing authorities. Similarly, there was no solid basis in the strategic documents (national) for that period: they did not provide any definition of revitalization. It was in the interest of the beneficiaries, as well as – partly – in the interest of those managing authorities to satisfy the local needs, especially those needs which were not considered the result of the shift to the post-industrial era, but rather as a result of numerous institutional and political events. Due to these features, the period 2007-2013 was dominated by infrastructure projects aimed at the quality of life but also efficient in terms of spending European money. It seems that there was an agreement between regional managing authorities and the benefi ciaries (potential voters) as to the way of spending the revitalization funding. This was understood differently at national level, but because institutions at this level were not involved directly in the urban regeneration (revitalization), their influence on regional units was minor. Even more so because the managing authorities were also interested in speeding up the process of spending European resources.
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Abstract

Isozyme, RAPD and AFLP markers were evaluated and compared for their ability to determine genetic similarity in a set of 18 parental lines of winter oilseed rape F<sub>1</sub> hybrids developed using CMS ogura. Five isozyme systems, 64 RAPD starters and 23 EcoRI+3/MseI+3 AFLP primer combinations generated 597 polymorphic markers. These polymorphic fragments were chosen for estimation of genetic similarity. Of the total number of polymorphic products, polymorphic zymograms constituted only 3.0% of the markers, 57 RAPD primers 37.7%, and 23 AFLP primer combinations 59.3%. The size of RAPD polymorphic products ranged from 564 to 2100 bp. On average there were four amplified bands per primer, with 61.0% polymorphism. The AFLP polymorphic fragments ranged from 72 to 1352 bp in size. AFLP assays generated 15 bands per primer pair on average and detected roughly four times more bands than with RAPD analysis. The genetic similarity coefficients based on all marker data range from 0.52 to 0.84. The correlation of genetic similarities based on RAPD and AFLP markers was 0.58. Estimated genetic similarity based on isozyme data was not correlated with genetic similarity derived from the two DNA-based markers. The dendrogram constructed with the three types of markers taken together grouped all the winter oilseed rape parental lines into several similar clusters. The genomic distribution and frequency of the RAPD and AFLP markers can serve well as estimators of genetic similarity between parental lines of F<sub>1</sub> CMS ogura hybrids
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Abstract

Papillophlebitis is an uncommon disease in clinical practice. We would like to present a case of a 29-year-old patient with atypical orbital pain and fl ashings, presenting relative aff erent pupillary defect and already typical of the disease entity: ophthalmoscopic picture of the fundus and big blind spot in perimetry. We present a complex and interdisciplinary diagnostic process that excludes general diseases such as hypertension, diabetes, coagulation disorders and neurological causes. We leave the only identifiable abnormality and potential source in the infl ammatory process of periodontal infl ammation and sinus jaw changes. We also describe the process of remitting the changes and fi nally a favorable end result of the primarily a very disturbing clinical picture that this disease may present.
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Abstract

The study examined changes in lysine decarboxylase (LDC), ornithine decarboxylase (ODC) and tyrosine decarboxylase (TyDC) activity in tissues of pea (Pisum sativum L.) infested by the pea aphid (Acyrthosiphon pisum Harris). The aphid induced increased ODC activity after one day and at two weeks. The effect was clearly systemic. TyDC activity increased after one day and at one week at feeding sites (aerial parts), while LDC activity increased only after one day of infestation and then decreased. Attack by aphids also affected enzyme activity in root tissues not directly damaged by the herbivores. The mechanisms of the response induced by pea aphid infestation in pea are discussed.
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