light elements
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The primary intention of this work was to bring information on the research, development, and construction of advanced thin film light sensitive elements. They are designed to be used for direct monitoring of the time variable with the help of preciously calibrated color change induced by irradiation in variable ranges of the light spectrum. Protection of many objects of cultural heritage includes also their protection against light. The protection would not be possible without measuring the dosage of radiance, to which every such object has been exposed. Another important application area comprises the warning of users that their exposure to the UV light upon outdoor activities has passed. It was shown that the proposed principles are ideally suited for such purposes.
- Klíčová slova
- barevná změna, fotokatalýza, dermatologické dozimetry, expoziční dozimetry, tenké světlocitlivé vrstvy,
- MeSH
- čas MeSH
- dávka záření * MeSH
- dozimetry klasifikace MeSH
- fotochemie MeSH
- fotometrie MeSH
- kolorimetrie MeSH
- lidé MeSH
- muzea MeSH
- sluneční spáleniny prevence a kontrola MeSH
- sluneční záření * škodlivé účinky MeSH
- slunění MeSH
- světlo škodlivé účinky MeSH
- ultrafialové záření klasifikace škodlivé účinky MeSH
- výstavy jako téma MeSH
- vztah dávky záření a odpovědi MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
The recent revision of the Acidithiobacillia class using genomic taxonomy methods has shown that, in addition to the existence of previously unrecognized genera and species, some species of the class harbor levels of divergence that are congruent with ongoing differentiation processes. In this study, we have performed a subspecies-level analysis of sequenced strains of Acidithiobacillus ferrooxidans to prove the existence of distinct sublineages and identify the discriminant genomic/genetic characteristics linked to these sublineages, and to shed light on the processes driving such differentiation. Differences in the genomic relatedness metrics, levels of synteny, gene content, and both integrated and episomal mobile genetic elements (MGE) repertoires support the existence of two subspecies-level taxa within A. ferrooxidans. While sublineage 2A harbors a small plasmid related to pTF5, this episomal MGE is absent in sublineage 2B strains. Likewise, clear differences in the occurrence, coverage and conservation of integrated MGEs are apparent between sublineages. Differential MGE-associated gene cargo pertained to the functional categories of energy metabolism, ion transport, cell surface modification, and defense mechanisms. Inferred functional differences have the potential to impact long-term adaptive processes and may underpin the basis of the subspecies-level differentiation uncovered within A. ferrooxidans. Genome resequencing of iron- and sulfur-adapted cultures of a selected 2A sublineage strain (CCM 4253) showed that both episomal and large integrated MGEs are conserved over twenty generations in either growth condition. In turn, active insertion sequences profoundly impact short-term adaptive processes. The ISAfe1 element was found to be highly active in sublineage 2A strain CCM 4253. Phenotypic mutations caused by the transposition of ISAfe1 into the pstC2 encoding phosphate-transport system permease protein were detected in sulfur-adapted cultures and shown to impair growth on ferrous iron upon the switch of electron donor. The phenotypic manifestation of the △pstC2 mutation, such as a loss of the ability to oxidize ferrous iron, is likely related to the inability of the mutant to secure the phosphorous availability for electron transport-linked phosphorylation coupled to iron oxidation. Depletion of the transpositional △pstC2 mutation occurred concomitantly with a shortening of the iron-oxidation lag phase at later transfers on a ferrous iron-containing medium. Therefore, the pstII operon appears to play an essential role in A. ferrooxidans when cells oxidize ferrous iron. Results highlight the influence of insertion sequences and both integrated and episomal mobile genetic elements in the short- and long-term adaptive processes of A. ferrooxidans strains under changing growth conditions.
Seabuckthorn (Hippophae rhamnoides) is a dioecious shrub commonly used in the pharmaceutical, cosmetic, and environmental industry as a source of oil, minerals and vitamins. In this study, we analyzed the transposable elements and satellites in its genome. We carried out Illumina DNA sequencing and reconstructed the main repetitive DNA sequences. For data analysis, we developed a new bioinformatics approach for advanced satellite DNA analysis and showed that about 25% of the genome consists of satellite DNA and about 24% is formed of transposable elements, dominated by Ty3/Gypsy and Ty1/Copia LTR retrotransposons. FISH mapping revealed X chromosome-accumulated, Y chromosome-specific or both sex chromosomes-accumulated satellites but most satellites were found on autosomes. Transposable elements were located mostly in the subtelomeres of all chromosomes. The 5S rDNA and 45S rDNA were localized on one autosomal locus each. Although we demonstrated the small size of the Y chromosome of the seabuckthorn and accumulated satellite DNA there, we were unable to estimate the age and extent of the Y chromosome degeneration. Analysis of dioecious relatives such as Shepherdia would shed more light on the evolution of these sex chromosomes.
- MeSH
- chromozomy rostlin * MeSH
- DNA rostlinná genetika MeSH
- fylogeneze MeSH
- genom rostlinný MeSH
- Hippophae genetika MeSH
- molekulární evoluce MeSH
- pohlavní chromozomy * MeSH
- satelitní DNA * MeSH
- sekvenční analýza DNA metody MeSH
- transpozibilní elementy DNA * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Zhruba v poloviněmi nulého století se objevil v odborné a posléze i laické veřejnosti fenomén „informační exploze“ popisující pocit nečekaného všeobecného informačního zahlcení stále větším množstvím zveřejňovaných článků i knih, které již nebylomožno tehdy dostupnými prostředky přečíst, zpracovat a využívat. Nečekaný rozvoj veškerého výzkumu po druhé světové válce vedl totiž k neobvykle prudkému nárůstu nových dat a informací, jejichž rychlému zveřejňování napomáhala, zvláštěc estou elektronizace, i výrazná modernizace publikačních možností provázená vznikem řady nových časopisů. Šlo o jev celosvětový, který se záhy, přes jistou ideologicko-informační izolovanost za tehdejšího totalitního systému, objevil i v našem prostředí. Takové záplavěi nformací však v bibliograficko-dokumentačně- informační oblasti neodpovídal rozvoj nezbytných moderních postupů, které by nové informace rychle, přiměřeně k jejich vzniku, zpřístupňovaly netrpělivým uživatelům. Kritickým momentem úspěšnému vyřešení byl tehdy vznik celosvětového síťového propojení –wordwideweb, resp. internetu. Postupně se začalo dařit do náročného zpracování nových informací zavádět stále výkonnější informační technologie v čele s výpočetní technikou a možností síťového on-line přístupu. Mít k dispozici tuto techniku i potřebné programové postupy představovalo spolu s osvojením si příslušné informační a počítačové gramotnosti základní podmínky jak informační explozi řešit. Současné moderní technologie včetněrů zných uživatelsky příjemných vyhledavačů, rozcestníků a skladů dat, spolu s výkonnými bibliografickými databázemi umožňujícími i vstup do plnotextových zdrojů, dnes pak vrhají zcela jiný pohled na informační explozi vypadající zpočátku katastroficky. Samozřejmě, že je nutné najít finanční úhradu, jak si k tomu všemu zajistit přístup. Informační zabezpečení odborné práce, opírající se o takovýto základ, však představuje na prahu moderní informační společnosti jedinou možnost efektivní činnosti v jakékoliv oblasti. Je to také dobrá záruka jak předcházet případných dalším informačním záplavám.
The phenomenon of “Information explosion” emerged in the professional and later also in the unprofessional community in the middle of the twentieth century. It expresses feeling of an unexpected general congestion with increasing number of published articles and books, which are not possible to go through, process and use in the real time. Unexpected development of the science after the Second World War resulted in unusually high production of new data and information. Their fast release was enabled by modernization of the publication process together with an increase of the number of scientific journals. Despite the relative information isolationism during the totalitarian regiment, this worldwide process soon emerged also in our region. However, the overload in information was not balanced by modernization of methods in the bibliographic and librarian systems, which could bring the new information to the scientific community. The turning point in the transfer of information was the development of worldwide interconnection – the word wide web or the Internet. For the processing of new information it was possible to introduce gradually still more powerful information technologies based on computers with on-line connection to the Internet. To solve the information explosion it was necessary to possess such technology and necessary programs and to master the elements of information and computer know-how. Contemporary modern technology with various user-friendly search engines, catalogues, repositories, and with voluminous bibliographic databases enable the use of full-text sources and give a better view on the formerly catastrophically looking information explosion. Along with that it is necessary to find financial sources to cover the access to the system. Information support of the scientific work based on such possibilities represents in the brimof modern information society the only possibility of effective activity in any field. It is also a good way how to precede the possible next information overload.
- MeSH
- informační systémy MeSH
- informatika MeSH
- lékařská informatika MeSH
- přístup k informacím MeSH
- věda MeSH
- Publikační typ
- bibliografie MeSH
- databáze MeSH
- přehledy MeSH
De-etiolation is the first developmental process under light control allowing the heterotrophic seedling to become autotrophic. The phytohormones cytokinins (CKs) largely contribute to this process. Reversible phosphorylation is a key event of cell signaling, allowing proteins to become active or generating a binding site for specific protein interaction. 14-3-3 proteins regulate a variety of plant responses. The expression, hormonal regulation, and proteomic network under the control of 14-3-3s were addressed in tomato (Solanum lycopersicum L.) during blue light-induced photomorphogenesis. Two isoforms were specifically investigated due to their high expression during tomato de-etiolation. The multidisciplinary approach demonstrated that TFT9 expression, but not TFT6, was regulated by CKs and identified cis-regulating elements required for this response. Our study revealed >130 potential TFT6/9 interactors. Their functional annotation predicted that TFTs might regulate the activity of proteins involved notably in cell wall strengthening or primary metabolism. Several potential interactors were also predicted to be CK-responsive. For the first time, the 14-3-3 interactome linked to de-etiolation was investigated and evidenced that 14-3-3s might be involved in CK signaling pathway, cell expansion inhibition and steady-state growth rate establishment, and reprograming from heterotrophy to autotrophy. BIOLOGICAL SIGNIFICANCE: Tomato (Solanum lycopersicum L.) is one of the most important vegetables consumed all around the world and represents probably the most preferred garden crop. Regulation of hypocotyl growth by light plays an important role in the early development of a seedling, and consequently the homogeneity of the culture. The present study focuses on the importance of tomato 14-3-3/TFT proteins in this process. We provide here the first report of 14-3-3 interactome in the regulation of light-induced de-etiolation and subsequent photomorphogenesis. Our data provide new insights into light-induced de-etiolation and open new horizons for dissecting the post-transcriptional regulations.
- MeSH
- chromatografie afinitní MeSH
- mapy interakcí proteinů * MeSH
- proteiny 14-3-3 metabolismus MeSH
- proteomika * MeSH
- rostlinné proteiny metabolismus MeSH
- semenáček růst a vývoj MeSH
- Solanum lycopersicum růst a vývoj MeSH
- světlo * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Light-sheet fluorescence microscopy has emerged as a powerful platform for 3-D volumetric imaging in the life sciences. Here, we introduce an important step towards its use deep inside biological tissue. Our new technique, based on digital holography, enables delivery of the light-sheet through a multimode optical fibre--an optical element with extremely small footprint, yet permitting complex control of light transport processes within. We show that this approach supports some of the most advanced methods in light-sheet microscopy: by taking advantage of the cylindrical symmetry of the fibre, we facilitate the wavefront engineering methods for generation of both Bessel and structured Bessel beam plane illumination. Finally, we assess the quality of imaging on a sample of fluorescent beads fixed in agarose gel and we conclude with a proof-of-principle imaging of a biological sample, namely the regenerating operculum prongs of Spirobranchus lamarcki.
Recent studies on motility of Apicomplexa concur with the so-called glideosome concept applied for apicomplexan zoites, describing a unique mechanism of substrate-dependent gliding motility facilitated by a conserved form of actomyosin motor and subpellicular microtubules. In contrast, the gregarines and blastogregarines exhibit different modes and mechanisms of motility, correlating with diverse modifications of their cortex. This study focuses on the motility and cytoskeleton of the blastogregarine Siedleckia nematoides Caullery et Mesnil, 1898 parasitising the polychaete Scoloplos cf. armiger (Müller, 1776). The blastogregarine moves independently on a solid substrate without any signs of gliding motility; the motility in a liquid environment (in both the attached and detached forms) rather resembles a sequence of pendular, twisting, undulation, and sometimes spasmodic movements. Despite the presence of key glideosome components such as pellicle consisting of the plasma membrane and the inner membrane complex, actin, myosin, subpellicular microtubules, micronemes and glycocalyx layer, the motility mechanism of S. nematoides differs from the glideosome machinery. Nevertheless, experimental assays using cytoskeletal probes proved that the polymerised forms of actin and tubulin play an essential role in the S. nematoides movement. Similar to Selenidium archigregarines, the subpellicular microtubules organised in several layers seem to be the leading motor structures in blastogregarine motility. The majority of the detected actin was stabilised in a polymerised form and appeared to be located beneath the inner membrane complex. The experimental data suggest the subpellicular microtubules to be associated with filamentous structures (= cross-linking protein complexes), presumably of actin nature.
BACKGROUND: High-throughput sequencing (HTS) has revolutionized the way in which epigenetic research is conducted. When coupled with fully-sequenced genomes, millions of small RNA (sRNA) reads are mapped to regions of interest and the results scrutinized for clues about epigenetic mechanisms. However, this approach requires careful consideration in regards to experimental design, especially when one investigates repetitive parts of genomes such as transposable elements (TEs), or when such genomes are large, as is often the case in plants. RESULTS: Here, in an attempt to shed light on complications of mapping sRNAs to TEs, we focus on the 2,300 Mb maize genome, 85% of which is derived from TEs, and scrutinize methodological strategies that are commonly employed in TE studies. These include choices for the reference dataset, the normalization of multiply mapping sRNAs, and the selection among sRNA metrics. We further examine how these choices influence the relationship between sRNAs and the critical feature of TE age, and contrast their effect on low copy genomic regions and other popular HTS data. CONCLUSIONS: Based on our analyses, we share a series of take-home messages that may help with the design, implementation, and interpretation of high-throughput TE epigenetic studies specifically, but our conclusions may also apply to any work that involves analysis of HTS data.
The timing of seed germination is crucial for seed plants and is coordinated by internal and external cues, reflecting adaptations to different habitats. Physiological and molecular studies with lettuce and Arabidopsis thaliana have documented a strict requirement for light to initiate germination and identified many receptors, signaling cascades, and hormonal control elements. In contrast, seed germination in several other plants is inhibited by light, but the molecular basis of this alternative response is unknown. We describe Aethionema arabicum (Brassicaceae) as a suitable model plant to investigate the mechanism of germination inhibition by light, as this species has accessions with natural variation between light-sensitive and light-neutral responses. Inhibition of germination occurs in red, blue, or far-red light and increases with light intensity and duration. Gibberellins and abscisic acid are involved in the control of germination, as in Arabidopsis, but transcriptome comparisons of light- and dark-exposed A. arabicum seeds revealed that, upon light exposure, the expression of genes for key regulators undergo converse changes, resulting in antipodal hormone regulation. These findings illustrate that similar modular components of a pathway in light-inhibited, light-neutral, and light-requiring germination among the Brassicaceae have been assembled in the course of evolution to produce divergent pathways, likely as adaptive traits.
- MeSH
- Brassicaceae fyziologie účinky záření MeSH
- exprese genu účinky záření MeSH
- gibereliny metabolismus MeSH
- klíčení účinky záření MeSH
- kyselina abscisová metabolismus MeSH
- rostlinné geny * MeSH
- sluneční záření * MeSH
- transkriptom účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
