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Description of Intra-Annual Changes in Cambial Activity and Differentiation of Secondary Conductive Tissues of Aesculus hippocastanum Trees Affected by the Leaf Miner Cameraria ohridella
Get PDFAesculus hippocastanum trees are commonly infested by the leaf miner Cameraria ohridella, whose larval activity causes the destruction of the leaf parenchyma and induces defoliation. Pest attacks result in, e.g., production of smaller fruits and tree re-flowering in autumn. Concerning pest influence on stem structure only scarce information of narrower annual growth rings of wood has been published. Therefore, we determined the effect of the presence of the leaf miner infestation on intra-annual cambial activity and on differentiation of conductive tissues. These data were compared with phenological phases and pest activity. Pest feeding resulted in changes in onset, cessation and duration of cambial divisions, and differentiation of secondary xylem. The duration of cambial activity was about a month shorter in heavily infested trees and was connected with premature tree defoliation. Affected trees were characterised by a reduction in cambial divisions and earlier cessation of wood differentiation resulting in narrower wood rings. Furthermore, the infested trees exhibited altered wood structure, with more vessels of smaller diameters, however these changes did not affect its theoretical hydraulic conductivity. Interestingly, pest attack did not influence secondary phloem differentiation. The probable influence of long-term infestation on tree growth and condition was discussed.O
Multi-seasonal systematic camera-trapping reveals fluctuating densities and high turnover rates of Carpathian lynx on the western edge of its native range
Get PDFCamera-trapping and capture-recapture models are the most widely used tools for estimating densities of wild felids that have unique coat patterns, such as Eurasian lynx. However, studies dealing with this species are predominantly on a short-term basis and our knowledge of temporal trends and population persistence is still scarce. By using systematic camera-trapping and spatial capture-recapture models, we estimated lynx densities and evaluated density fluctuations, apparent survival, transition rate and individual's turnover during five consecutive seasons at three different sites situated in the Czech-Slovak-Polish borderland at the periphery of the Western Carpathians. Our density estimates vary between 0.26 and 1.85 lynx/100 km2 suitable habitat and represent the lowest and the highest lynx densities reported from the Carpathians. We recorded 1.5-4.1-fold changes in asynchronous fluctuated densities among all study sites and seasons. Furthermore, we detected high individual's turnover (on average 46.3 +- 8.06% in all independent lynx and 37.6 +- 4.22% in adults) as well as low persistence of adults (only 3 out of 29 individuals detected in all seasons). The overall apparent survival rate was 0.63 +- 0.055 and overall transition rate between sites was 0.03 +- 0.019. Transition rate of males was significantly higher than in females, suggesting male-biased dispersal and female philopatry. Fluctuating densities and high turnover rates, in combination with documented lynx mortality, indicate that the population in our region faces several human-induced mortalities, such as poaching or lynx-vehicle collisions. These factors might restrict population growth and limit the dispersion of lynx to other subsequent areas, thus undermining the favourable conservation status of the Carpathian population. Moreover, our study demonstrates that long-term camera-trapping surveys are needed for evaluation of population trends and for reliable estimates of demographic parameters of wild territorial felids, and can be further used for establishing successful management and conservation measures.Postprin
Auxin (IAA) and soluble carbohydrate seasonal dynamics monitored during xylogenesis and phloemogenesis in Scots pine
Get PDFThe metabolic activity of phytohormones and the accumulation of carbohydrates affect the reactivation of the cambial zone and the radial increment of woody plants. We aimed to monitor the dynamics of indole-3-acetic acid (IAA) concentration and amounts of soluble carbohydrates during xylem and phloem formation of one growing season (2015). Six sample trees of Scots pine (Pinus sylvestris L.), aged 80 years on average, growing in the Sobešice research site (404 m a.s.l.) in the Czech Republic were selected. We obtained microcore samples at weekly intervals by the Trephor tool method for cell formation analysis and spectrophotometric determination of IAA and soluble carbohydrate contents. We found that time of the highest concentration of IAA (last week of April) coincided with time of the maximum number of cells in the cambial zone and highest expansion of the cell enlargement stage. When the IAA concentration was too low to be measured, latewood tracheids started to form, and late phloem sieve cell formation ceased. The highest concentration of soluble carbohydrates was 200.40 +- 21.6 µg GLU per sample (May 14). This coincided with the fastest weekly xylem cell increment. This research shows that IAA and soluble carbohydrate dynamics directly affects xylem and phloem formation.O
Ayahuasca in the Czech Republic
Get PDFAyahuasca is a preparation used in "traditional Amazonian medicine". This book focuses on its utilization in the Czech Republic and the possibilities of using it for therapeutic purposes in local conditions. The book contains a classification of rituals and the characteristics of their organizers and participants. An on-line questionnaire survey was conducted among ayahuasca users from November 1, 2015, to December 31, 2016. The research sample consists of 46 respondents (23 women and 23 men) that once took part in some rituals. Similarly, semi-structured interviews with an average length of 50 minutes recorded with informants. Grounded theory method was applied to analyse the interviews conducted. The results confirm that rituals are adapted according to the needs of the users. The respondents use ayahuasca not only because of healing, but also for spiritual and religious reasons, curiosity/experiment and personality development. In local conditions, the therapeutic potential of ayahuasca lies primarily in the treatment of lifestyle diseases.O
Ayahuasca in the Czech Republic
No full textAyahuasca je přípravek používaný v "tradiční amazonské medicíně". Tato kniha je zaměřena na její užívání v České republice a možnosti jejího terapeutického využití v místních podmínkách. Publikace obsahuje klasifikaci rituálů a charakteristiky jejich pořadatelů a účastníků. Terénní výzkum mezi uživateli ayahuascy byl v návaznosti na on-line dotazníkové šetření realizován od 1. 11.2015 do 31. 12. 2016. Výzkumný vzorek tvoří 46 osob (23 žen a 23 mužů), které se minimálně jednou zúčastnily nějakého typu rituálu. S těmito osobami byly nahrány semi-strukturované rozhovory o průměrné délce 50 min., které byly následně analyzovány metodou zakotvené teorie. Výsledky výzkumu potvrzují, že rituály se uzpůsobují potřebám uživatelů. Ti ayahuascu užívají nejen kvůli léčení, ale také ze spirituálních a náboženských důvodů, ze zvědavosti/experimentu a kvůli osobnostnímu rozvoji. Terapeutický potenciál ayahuascy v místních podmínkách spočívá ze-jména v léčbě civilizačních chorob.Ayahuasca is a preparation used in traditional Amazonian medicine". This book focuses on its utilization in the Czech Republic and possibilities of its utilization for therapeutic purposes in local conditions. The publication contains a classification of rituals and the characteristics of their organizers and participants. Following on-line questionnaire survey, the field work among ayahuasca users was done from November 1, 2015 to December 31, 2016. The research sample consists of 46 persons (23 women and 23 men) who at least once took part in some type of ritual. There were the semi-structured inter-views with an average length of 50 minutes recorded with informants. These interviews were subsequently analyzed by the Grounded theory method. The results confirm that rituals are adapted according to the needs of the users. They use ayahuasca not only because of healing, but also for spiritual and religious reasons, curiosity/experiment and personality development. In local conditions, the therapeutic potential of ayahuasca lies primarily in the treatment of lifestyle diseases.Published Versio
Open Source Tools for Text Processing
Get PDFPublished VersionThis book contains study material for the course Open source word processing tools intended for education at the university level. It is the result of a project dealing with the application of open source tools in teaching. It shows that even for demanding publications there is no need to use expensive licensed software, and it is even possible to efficiently create documents that are difficult to implement in other environments or with a high proportion of manual work. The text emphasizes an efficient approach to document processing – the wide use of so-called structural (semantic) markup that allow separating the document from its visual form, thus achieving greater flexibility and reusability of the processed material. The technological tool is the Open Source system XƎLATEX widely used in the scientific and professional field, in education and in selected publishing houses. It is a principle whose mastery brings significant advantages to users when processing professional texts, such as various seminar and final theses, articles, proceedings and other publications. Together with the individual elements of the XƎLATEX system, the book also contains an explanation of the necessary typographical principles and rules applied in common types of documents. It thus brings a complete view of document processing
Valuation of government bonds: The exchange rate is an important aspect
Get PDFInterest rates are currently very low in the countries. In these countries bonds are issued with low or negative yields. In this paper, I empirically investigate the factors that affect the price of bonds. I follow international arbitrage pricing theory to determine the relationship between factors and the price of bonds. The international arbitrage pricing theory applies a multi-linear regression model. The regression model is used for emerging markets and developing markets separately. I have a unique data set of 46 countries. The main data are the monthly returns on government bonds in the period 2010 - 2015. Exchange risk influences the bond prices. Currency movements can bring further yield for investors.O
Efficiency comparison and efficiency development of the metallurgical industry in the EU: Parametric and non-parametric approaches
Get PDFThis article deals with the development of technical (production) efficiency in the metallurgical industry in EU countries with an emphasis on the situation in the Czech Republic. The efficiency of individual countries was estimated for the period from 1995 to 2015. The parametric stochastic frontier analysis method with different settings was chosen to estimate efficiency and the results were verified using a competitive non-parametric data envelopment analysis method. It was found that during the period under review, there was an average increase in efficiency in the metallurgical industry. The largest increase in efficiency (confirmed by all types of models) was observed in the Czech Republic. A visible positive efficiency shift was also recorded in Spain and Greece. Surprisingly, there has been a decline in efficiency in Sweden and Italy.O
Graphene Oxide as a Nanocarrier for Biochemical Molecules: Current Understanding and Trends
Get PDFThe development of an advanced and efficient drug delivery system with significant improvement in its efficacy and enhanced therapeutic value is one of the critical challenges in modern medicinal biology. The integration of nanomaterial science with molecular and cellular biology has helped in the advancement and development of novel drug delivery nanocarrier systems with precision and decreased side effects. The design and synthesis of nanocarriers using graphene oxide (GO) have been rapidly growing over the past few years. Due to its remarkable physicochemical properties, GO has been extensively used in efforts to construct nanocarriers with high specificity, selectivity, and biocompatibility, and low cytotoxicity. The focus of this review is to summarize and address recent uses of GO-based nanocarriers and the improvements as efficient drug delivery systems. We briefly describe the concepts and challenges associated with nanocarrier systems followed by providing critical examples of GO-based delivery of drug molecules and genes. Finally, the review delivers brief conclusions on the current understanding and prospects of nanocarrier delivery systems.O
Survey and diversity of grapevine pinot gris virus in algeria and comprehensive high-throughput small rna sequencing analysis of two isolates from vitis vinifera cv. Sabel revealing high viral diversity
Get PDFGrapevine Pinot gris virus (GPGV) is a putative causal agent of grapevine leaf mottling and deformation disease that has been reported worldwide throughout the grapevine-growing regions. Fifty-four grapevines collected from five Algerian grapevine-growing regions were tested for the presence of GPGV in phloem tissues. Eight of the tested grapevines were infected by GPGV. Viromes of two selected Vitis vinifera cv. Sabel grapevines infected by GPGV and showing virus-like symptoms were analyzed by small RNA sequencing. Phylogenetic analyses of the partial coding sequence (cds) of the RNA-dependent RNA polymerase (RdRp) domain showed that all Algerian GPGV isolates were grouped with some already-described asymptomatic isolates. This study provides the first survey of the occurrence of GPGV in Algeria. Moreover, Grapevine fleck virus, Grapevine rupestris stem pitting-associated virus, Grapevine virus B, Grapevine rupestris vein feathering virus, Hop stunt viroid and Grapevine yellow speckle viroid 1 were detected in Algeria for the first time.O