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Desiccation in green algae: mechanisms and aquisition of tolerance
Belza, Václav Cedrik ; Pichrtová, Martina (advisor) ; Němcová, Yvonne (referee)
This thesis summarizes the current knowledge of the mechanisms that allow green algae to tolerate even severe desiccation. It provides a comprehensive overview, ranging from the definition of desiccation stress and its impacts on algal cells, through mechanisms that algae employ in defense, to the evolutionary background as well as a synthesis of recent research on the acquisition of desiccation tolerance and factors conditioning it. The first chapter defines the desiccation stress itself and breaks down the processes by which it can damage algal cells, including both morphological and physiological effects. The second chapter discusses diverse mechanisms involved in protection against desiccation. From mechanisms aimed at prevention of water loss (e.g. mucilage production or modification of cell wall permeability), through mechanisms that cause desiccation tolerance (e.g. accumulation of antioxidants, stabilization of proteins and phospholipids etc.), to the formation of resilient life stages. The third chapter is devoted to the evolutionary-historical background behind the emergence of desiccation tolerance per se and overview in which algal groups it is observable today. The last section is a synthesis of modern knowledge regarding acquisition of desiccation tolerance during algal life and...
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Interaction of microwave radiation with moisture in porous building materials
Paťha, Martin ; Šuhajdová, Eva (referee) ; Šuhajda, Karel (advisor)
This thesis deals with interaction of microwave radiation with wet in porous material. It examines the distribution of the temperature field, the efficiency of the method and the financial demands of the method. The most important part of this thesis was an experiment, from which all important values ??were based. The first part deals with the necessary theory and the second part is the experiment itself. The experiment was carried out for three levels of material wet. Eight samples were used for this experiment, which remained unchanged throughout the experiment. The thesis draws on previous researches that were carried out on this or similar topic.
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Algal and Cyanobacterial Adaptations to Low Temperature and Desiccation
Jimel, Matouš ; Elster, Josef (advisor) ; Košťál, Vladimír (referee)
Algae and cyanobacteria, due of their evolutionary antiquity, are widely distributed primary producers that can withstand extreme environmental stresses. Low temperature, freezing and melting, and desiccation and rewetting, are common stresses prevalent mainly in polar regions and in winter seasons of temperate areas. In terms of physiological effects, these types of stresses share similar effects or are closely related to one another. Low temperatures and desiccation exert a variety of stresses that need to be negated or lessened by adaptations. Specifically, adaptations to chill, freeze, and desiccation stresses will be discussed, as well as strategies that allow for stress avoidance or resistant morphological adaptations. In this thesis, characteristics, functions and mechanisms of these adaptations and stresses are reviewed, as well as potential biotechnological uses of said adaptations. Key words: algae, cyanobacteria, freezing, chill, desiccation, abiotic stress, cryoprotectants, osmoprotectants, akinetes, cryoinjury
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The effect of desiccation on streptophyte algae - mechanisms of stress resistance
Pošmourný, Martin ; Pichrtová, Martina (advisor) ; Vosolsobě, Stanislav (referee)
In this thesis I dealt streptophyta algae resistance against desiccation. Even though the area previously devoted only a few people. Considerable amount of work in recent years has been published on the subject. They were found interesting information and discovered new facts. Research continues on and on, and it would be useful to look at what was observed. I believe that understanding this phenomenon is the key to understanding some of the events in the evolution of nature and realizing how tough life can be on the very border of its possible occurrence. I tried to sort out the current knowledge about the mechanisms of stress resistance streptophyta algae and hope that I obtained an overview will help me understand better this issues. So far, it has been observed several approaches to defend against drying. Preventing drying, adaptation to water shortage and tolerance to desiccation. Among the preventive methods of defense include creating clusters of cells, multi-layered mats or secretion mucilage. As an adaptation to the lack of water algae evolved more complex answers in the form of changes in ultrastructure, or regulation of physiological processes. Klebsormidium is capable of half an hour to start the production of significant quantities callose and incorporate it into the cell wall. This...
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Algal and Cyanobacterial Adaptations to Low Temperature and Desiccation
Jimel, Matouš ; Elster, Josef (advisor) ; Košťál, Vladimír (referee)
Algae and cyanobacteria, due of their evolutionary antiquity, are widely distributed primary producers that can withstand extreme environmental stresses. Low temperature, freezing and melting, and desiccation and rewetting, are common stresses prevalent mainly in polar regions and in winter seasons of temperate areas. In terms of physiological effects, these types of stresses share similar effects or are closely related to one another. Low temperatures and desiccation exert a variety of stresses that need to be negated or lessened by adaptations. Specifically, adaptations to chill, freeze, and desiccation stresses will be discussed, as well as strategies that allow for stress avoidance or resistant morphological adaptations. In this thesis, characteristics, functions and mechanisms of these adaptations and stresses are reviewed, as well as potential biotechnological uses of said adaptations. Key words: algae, cyanobacteria, freezing, chill, desiccation, abiotic stress, cryoprotectants, osmoprotectants, akinetes, cryoinjury
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Interaction of microwave radiation with moisture in porous building materials
Paťha, Martin ; Šuhajdová, Eva (referee) ; Šuhajda, Karel (advisor)
This thesis deals with interaction of microwave radiation with wet in porous material. It examines the distribution of the temperature field, the efficiency of the method and the financial demands of the method. The most important part of this thesis was an experiment, from which all important values ??were based. The first part deals with the necessary theory and the second part is the experiment itself. The experiment was carried out for three levels of material wet. Eight samples were used for this experiment, which remained unchanged throughout the experiment. The thesis draws on previous researches that were carried out on this or similar topic.
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The effect of desiccation on streptophyte algae - mechanisms of stress resistance
Pošmourný, Martin ; Pichrtová, Martina (advisor) ; Vosolsobě, Stanislav (referee)
In this thesis I dealt streptophyta algae resistance against desiccation. Even though the area previously devoted only a few people. Considerable amount of work in recent years has been published on the subject. They were found interesting information and discovered new facts. Research continues on and on, and it would be useful to look at what was observed. I believe that understanding this phenomenon is the key to understanding some of the events in the evolution of nature and realizing how tough life can be on the very border of its possible occurrence. I tried to sort out the current knowledge about the mechanisms of stress resistance streptophyta algae and hope that I obtained an overview will help me understand better this issues. So far, it has been observed several approaches to defend against drying. Preventing drying, adaptation to water shortage and tolerance to desiccation. Among the preventive methods of defense include creating clusters of cells, multi-layered mats or secretion mucilage. As an adaptation to the lack of water algae evolved more complex answers in the form of changes in ultrastructure, or regulation of physiological processes. Klebsormidium is capable of half an hour to start the production of significant quantities callose and incorporate it into the cell wall. This...
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Effect of harvest interval from the end of the vegetation potato on the occurrance Rhizoctonia cancer
ZENÁHLÍK, David
The thesis on the topic of the influence of the time period distance of the harvest from the end of the vegetation on the occurrence of "potato fenkines on the bulbs." There were 11 varieties of the potatoes chosen for the observation. Their vegetation was terminated by the desication resource called Reglone. From the end of the terminated vegetation during 10 days until the harvest there were 4 samples taken and they were evaluated on the occurrence and it's percentage of the "potato flakiness on the bulbs" in accordance with the scale of Wenzel and Demel (1976). There were there varietes selected for the evaluation; Flavia (VR), Riviera (VR), Rosara (VR), Merida (R), Adéla (R), the Baccara (R), Marabel (R), Ditta (PR), Laura (PR), Maréna (PP) and Saturn (PP). The achieved results of the "potato flakiness" weere evalunted statistically. The aim of the evlution of the ("potato flakiness on their bulls") Rhizoctonia solani. The term of the vegetation termination depends on the grover and must be in written documentation. The harvest alome can follow after the the drawal period in the desiccation resource, which uswally 15 days. The results indicale that whem the harvest of the potatoes is made at the proper time after the termination of the vegetation, the potato bulls are withhout any largen percentage accurence of the "flakiness". The results achieved during the years 2012 and 2013 indicate that in early implementation off all the working operations important for the potato growing, which begin with sorting out, followed by plantig, care, chemical sprays, selection, parades, desiccation and the harvest, the "flakiness" dinďt exceed 5% of the occurence. Another results indicate that the taken bulls were undamaged and the difference of the occurrence of the "flakiness"on each sample appeared in a variety of ways. The years of abseving the experiment proved that there was an increase in the "flakiness" on the surface for a given time period.
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