Reproducibility and accuracy of polarization mode dispersion measurements

Diplomová práca je rozdelená na dve časti. Prvá časť sa nesie v teoretickom duchu. Zaoberá sa matematicky a slovne všeobecným vznikom disperzií. Sústreďuje sa na vznik chromatickej a polarizačnej vidovej disperzie. V súvislosti s normou ITU-T sú tiež spomínané druhy optických vlákien pre kategóriu G.65X. Ďalšia pozornosť sa upriamuje najskôr na kompenzáciu a následne na meranie oboch spomínaných disperzií. Práca popisuje aj analyzátory merania a ich hlavné vlastnosti. Druhá časť práce sa venuje praktickým meraniam polarizačnej vidovej disperzie. Zo začiatku sú popísané použité komponenty využité pri zostrojení a meraní optických topológii, následne je spracovaný detailný rozbor každej optickej trasy. Záver tejto časti sa venuje výsledkom každej meracej metódy a ich vzájomným porovnaním. Merania v teplotnej komore sú predmetom ďalšej praktickej časti, ktorá zo začiatku zaznamenáva základné vlastnosti teplotnej komory. Dodatočne nasleduje popis meraní, analýza a záverečné hodnotenie v závislosti hodnoty polarizačnej vidovej disperzie na teplote.Thesis is divided into two parts. The first part is written rather in theoretical way. It deals with general formation of the dispersion mathematically and verbally. It focuses on the chromatic and polarization mode dispersion. Different types of optical fibers for category G.65X are mentioned as well in connection with the ITU-T. Further attention is drawn first to compensation and then the measurement both of the mentioned dispersions. The thesis describes also analyzers and their main features. The second part is devoted to practical measurements of polarization mode dispersion. In the beginning there are described the components used for construction of the optical measurements and topologies. It is followed by an analysis of an each optical link. The results of these measurement methods and their mutual comparisons are at the end of this section. Measurements in temperature chamber is the subject of a further practical part, which from the beginning captures the essential features of the temperature chamber. This is followed by a description of the measurements, analyses and final valuation depending on the amount of polarization mode dispersion versus the temperature.

Simulation and measurement of dispersions in optical access networks

Práca sa zaoberá detailným popisom chromatickej disperzie–CD a polarizačnej vidovej disperzie–PMD. V teoretickej časti sú rozoberané slovne i matematicky princípy vzniku disperzií, ďalej rozdelenie disperzií z pohľadu jednovidových a mnohovidových optických vlákien cez kompenzáciu, či už vláknami (chromatická disperzia) alebo systémom (polarizačná vidová disperzia). Teoretická časť nahliadne aj do normy ITU-T z pohľadu vlákien konkrétne G.652, G.653, G.655, G.656, G.657, ktoré sú opísané a porovnané. Predposledná časť sa zaoberá podstatnou témou a to meraním oboch spomínaných disperzií. Záver teoretickej časti sa venuje optickým prístupovým sieťam, kde je popísaná optická prístupová sieť ako taká, jej delenie a ku koncu sú popísané jednotlivé druhy sietí ako APON/BPON, GPON, EPON, 10GEPON a XG-PON. Praktická časť sa delí na meranie disperzií (EXFO FTB-5700) a simuláciu disperzií (OptSim). Oba kroky využívali rovnaký druh a dĺžku vlákna (6 km G.653, 20, 60 km G.652). Podľa vopred vytvorených meraných a simulačných schém sa získali parametre vlákien, ktoré sa na záver porovnali.Thesis deals with detailed description of the chromatic dispersion–CD and polarization mode dispersion–PMD. In theoretical part is dismantled at the beginning of words and mathematical principles of dispersion, further distribution of dispersion in terms of single-mode and multi-mode optic fibers through compensation, either fibers (chromatic dispersion) or systems (polarization mode dispersion). Theoretical part also consult the standard ITU-T specifically in term of fibers G.652, G.653, G.655, G.656, G.657, are described and compared. The penultimate section deals with major subject and by measuring both of the above dispersions. Finally, the theoretical part is devoted to optical access networks, which describes the optical access network such as its division and at the end describes the different types networks as APON/BPON, GPON, EPON, 10GEPON and XG-PON. The practical part is divided into measurement dispersions (EXFO FTB-5700) and simulation dispersions (OptSim). Both steps use the same type and length of fiber (6 km G.653, 20, 60 km G.652). According before creating the measured and simulation diagrams are obtained fibres parameters, which are finally compared.

Evidence of relationship between strain and In-incorporation:Growth of N-polar In-rich InAlN buffer layer by OMCVD

International audienc

Print Management System Model in a Large Organization

This article is focused on the analysis and solution of the issue of a printing system model in a large organization. It provides an overview of the current stat29e of the organization and its current printing system. Based on the information about strengths and weaknesses, the most suitable solution for the given organization was designed and subsequently implemented. The created design meets all the requirements required by the company, while minimizing the threats that the deployment of the new system and the resulting changes may have. The work also describes various ways of dealing directly with change, whether when dealing with the old printing system or preparing employees for its change. The new system brings clear unification of the press, its monitoring and administration under the supervision of its own employees without the need for external companies or support

Quercetin Ameliorates Testicular Damage in Zucker Diabetic Fatty Rats through Its Antioxidant, Anti-Inflammatory and Anti-Apoptotic Properties

The aim of this study was to investigate the effects of quercetin (QUE) on the testicular architecture as well as markers of oxidative, inflammatory, and apoptotic profile of male gonads in Zucker diabetic fatty (ZDF) rats suffering from Type 2 diabetes mellitus in the absence or presence of obesity. QUE was administered orally at a dose of 20 mg/kg/day for 6 weeks. Morphometric analysis revealed that QUE treatment led to an improvement in testicular appearance, particularly in the case of Obese ZDF rats. Furthermore, a significant stabilization of the antioxidant capacity (p < 0.05), superoxide dismutase and catalase activity (p < 0.01), with a concomitant decrease in lipid peroxidation (p < 0.05) were observed in Obese ZDF animals exposed to QUE. Our data also indicate a significant decline in the levels of interleukin (IL)-1 (p < 0.05), IL-6 (p < 0.01) and tumor necrosis factor alpha (p < 0.001) following QUE supplementation to Obese ZDF rats in comparison with their respective control. Finally, a significant down-regulation of the pro-apoptotic BAX protein (p < 0.0001) was observed in Obese ZDF rats administered with QUE, while a significant Bcl-2 protein overexpression (p < 0.0001) was recorded in Lean ZDF animals when compared to their untreated control. As such, our results suggest that QUE is a potentially beneficial agent to reduce testicular damage in ZDF rats with Type 2 diabetes mellitus by decreasing oxidative stress, chronic inflammation, and excessive cell loss through apoptosis

Identification of Bacterial Profiles and Their Interactions with Selected Quality, Oxidative, and Immunological Parameters of Turkey Semen

This study focused on the identification of naturally occurring bacteria in the reproductive fluid and impact on the quality of ejaculates obtained from the turkey breed British United Turkeys (BUT) Big 6 (n = 60). We determined possible relationships between the bacterial load and advanced sperm quality parameters that are important for effective artificial insemination and high fertility, as well as the concentration of selected antimicrobial proteins and pro-inflammatory markers of turkey semen. Sperm motility was assessed with computer-assisted sperm analysis (CASA), while the membrane and acrosome integrity were examined with smearing and staining methods. Reactive oxygen species (ROS) generation was quantified via luminometry, sperm DNA fragmentation was evaluated using the TUNEL assay, and the JC-1 assay was applied to evaluate the mitochondrial membrane potential. Cell lysates were prepared to investigate the extent of lipid and protein oxidation. Furthermore, levels of interleukins 1 and 6 (IL-1, IL-6), C-reactive protein, cathelicidin, and β-defensin were quantified in the seminal plasma using the ELISA method. The most dominant species identified by the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry was Escherichia coli, Proteus mirabilis, Staphylococcus lentus, and Citrobacter braakii. The bacterial load had a negative effect on the sperm motility (p < 0.001), as well as membrane (p < 0.05) and acrosome integrity (p < 0.01). A strong positive relationship between the bacterial load and DNA fragmentation (p < 0.001) was detected as well. Positive associations were recorded between the increasing presence of bacteria, ROS overgeneration (p < 0.001), and a subsequent oxidative damage to the proteins (p < 0.001) and lipids (p < 0.01). It was revealed that the antimicrobial peptides β-defensin (p < 0.001) and cathelicidin (p < 0.001) had a positive relationship with the motility. In contrast, pro-inflammatory markers, such as IL-1 (p < 0.001) and IL-6 (p < 0.001), had a negative impact on the motion behavior of turkey spermatozoa. Our results suggest that the semen quality may be notably affected by the bacterial quantity as well as quality. It seems that bacteriospermia is associated with inflammatory processes, oxidative stress, sperm structural deterioration, and a subsequent risk for a failed artificial insemination in turkey breeding

Seminal Bacterioflora of Two Rooster Lines: Characterization, Antibiotic Resistance Patterns and Possible Impact on Semen Quality

This study aimed to characterize the bacterial profiles and their association with selected semen quality traits among two chicken breeds. Thirty Lohmann Brown and thirty ROSS 308 roosters were selected for semen quality estimation, including sperm motility, membrane and acrosome integrity, mitochondrial activity, and DNA fragmentation. The oxidative profile of the semen, including the production of reactive oxygen species (ROS), antioxidant capacity, protein, and lipid oxidation, were assessed as well. Moreover, the levels of pro-inflammatory cytokines, including tumor necrosis factor alpha (TNF-α), interleukins 1 and 6 (IL-1, IL-6) and C-reactive protein, as well as the concentrations of selected antibacterial proteins (cathelicidin, β-defensin and lysozyme) in the seminal plasma were evaluated with the enzyme-linked immunosorbent assay. The prevailing bacterial genera identified by the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry were Citrobacter spp., Enterococcus spp., Escherichia spp. and Staphylococcus spp. While the bacterial load was significantly higher in the ROSS 308 line (p Escherichia coli presented with significantly (p p < 0.05) higher levels of β-defensin and lysozyme were found in the semen collected from the ROSS 308 roosters, which was characterized by a higher quality in comparison to the Lohmann Brown roosters. In conclusion, we emphasize the criticality of bacteriospermia in the poultry industry and highlight the need to include a more complex microbiological screening of semen samples designated for artificial insemination