Campylobacter concisus Impairs Sodium Absorption in Colonic Epithelium via ENaC Dysfunction and Claudin-8 Disruption

The epithelial sodium channel (ENaC) can increase the colonic absorptive capacity for salt and water. Campylobacter concisus is a common pathogenic epsilonproteobacterium, causing enteritis and diarrhea. It can induce barrier dysfunction in the intestine, but its influence on intestinal transport function is still unknown. Therefore, our study aimed to characterize C. concisus effects on ENaC using the HT-29/B6-GR/MR (epithelial cell line HT-29/B6 transfected with glucocorticoid and mineralocorticoid receptors) cell model and mouse colon. In Ussing chambers, C. concisus infection inhibited ENaC-dependent Na+ transport as indicated by a reduction in amiloride-sensitive short circuit current (-55%, n = 15, p < 0.001). This occurred via down-regulation of β- and γ-ENaC mRNA expression and ENaC ubiquitination due to extracellular signal-regulated kinase (ERK)1/2 activation, predicted by Ingenuity Pathway Analysis (IPA). In parallel, C. concisus reduced the expression of the sealing tight junction (TJ) protein claudin-8 and induced claudin-8 redistribution off the TJ domain of the enterocytes, which facilitates the back leakage of Na+ ions into the intestinal lumen. In conclusion, C. concisus caused ENaC dysfunction via interleukin-32-regulated ERK1/2, as well as claudin-8-dependent barrier dysfunction-both of which contribute to Na+ malabsorption and diarrhea

Talent management motives and practices in an emerging market: A comparison between MNEs and local firms

This paper compares the differences in talent management motivations and practices between MNEs and local firms in the emerging market of Turkey. It uses institutional theory and the resource based view of the firm to explain these differences. Examining data from 201 firms the findings show significant differences between the talent management motives of MNEs and local firms, with MNEs having more tactical motivations for their talent management systems. The study also shows significant differences in the talent management practices between MNEs and local firms, with MNEs implementing more robust systems of talent management overall. The findings indicate that the motives for TM and the practices that are pursued by organizations are society-bound. The study of TM motives and practices has to be framed within the context of the institution as this shapes the way in which actors perceive and respond to environmental and organizational stimuli and the extent to which they seek to protect the rules that shape and structure their environments

Hybrid parallelization of a seeded region growing segmentation of brain images for a GPU cluster

The introduction of novel imaging technologies always carries new challenges regarding the processing of the captured images. 3D Polarized Light Imaging (PLI) is such a new technique. It enables the mapping of single nerve fibers in postmortem human brains in unprecedented detail. Due to the very high resolution at sub-millimeter scale, an immense amount of image data has to be reconstructed three-dimensionally before it can be analyzed. Some of the steps in the reconstruction pipeline require a previous segmentation of the large images. This task of image processing creates black-and-white masks indicating the object and background pixels of the original images. It has turned out that a seeded region growing approach achieves segmentation masks of the desired quality. To be able to process the millions of images acquired with PLI for a single human brain, the region growing has to be parallelized for a supercomputer. However, the choice of the seeds as a preprocessing step of the region growing has to be automated in order to enable a parallel execution. A hybrid parallelization has been applied to the automated seeded region growing to exploit the architecture of a GPU cluster. The hybridity consists of an MPI based parallelization on the CPUs and the execution of some well-chosen, data-parallel subtasks on the GPUs as accelerators. This approach achieves a linear speedup behavior so that the runtime can be reduced to a reasonable amount

High Precision Sensor of Antenna System Position

V první části se práce zabývá popisem různých metod řešení snímání velikosti elevace a azimutu anténního systému. Dále se pak diagnostikou předchozího systému, který se v předchozích letech příliš neosvědčil kvůli vzniku chyb nastavovaných úhlů. Ve druhé části se práce zabývá návrhem a konstrukcí snímacího systému, který je založen na absolutním snímání úhlů natočení, s integrovanou ochranou proti přetočení i nulovací funkcí pro uvedení systému do výchozího stavu. V závěru je pak shrnutí dosažených výsledků praktické realizace.Katedra aplikované elektroniky a telekomunikacíObhájenoThe thesis in the first part description the different methods of scan size elevation and azimuth antenna system. Next the thesis deals with the diagnosis of the previous system, which in previous years it work with errors of set angles. In the second part of the thesis deals with the design of a new sensor system, which is based on absolute sensing rotation angles, with integrated angle limit protection and reset functions for the system default state. At the end is a summary of the results of practical implementation