Preparation of SNOM probes with special properties

Tato bakalářská práce je zaměřena na přípravu funkčních sond z konvenčního dutého optického vlákna a jejich testování při měření na aparatuře SNOM. Dále se zde studují speciální vlastnosti těchto sond především jejich využití jako "nanoGIS". Předpokládá se vyřešení hlavních problémů spojených s přípravou sondy jako je například leptání vlákna zevnitř.This bachelor thesis is focused on preparation and testing of probes from a hollow optical fibre and their application in SNOM measurement. Further, special properties of these probes are studied, namely their use as a "nanoGIS". The main problems as etching from the inside are assumed to be solved.

Loss of flotillin expression results in weakened desmosomal adhesion and Pemphigus vulgaris-like localisation of desmoglein-3 in human keratinocytes

Desmosomes are adhesion plaques that mediate cell-cell adhesion in many tissues, including the epidermis, and generate mechanical resistance to tissues. The extracellular domains of desmosomal cadherin proteins, desmogleins and desmocollins, are required for the interaction with cadherins of the neighbouring cells, whereas their cytoplasmic tails associate with cytoplasmic proteins which mediate connection to intermediate filaments. Disruption of desmosomal adhesion by mutations, autoantibodies or bacterial toxins results in severe human disorders of e.g. the skin and the heart. Despite the vital role of desmosomes in various tissues, the details of their molecular assembly are not clear. We here show that the two members of the flotillin protein family directly interact with the cytoplasmic tails of desmogleins. Depletion of flotillins in human keratinocytes results in weakened desmosomal adhesion and reduced expression of desmoglein-3, most likely due to a reduction in the desmosomal pool due to increased turnover. In the absence of flotillins, desmoglein-3 shows an altered localisation pattern in the cell-cell junctions of keratinocytes, which is highly similar to the localisation observed upon treatment with pemphigus vulgaris autoantibodies. Thus, our data show that flotillins, which have previously been connected to the classical cadherins, are also of importance for the desmosomal cell adhesion

Multireflector Antennas - Cascaded Structures with Frequency Selective Surfaces

The problem of increasing the gain of directional multiband antennas is solved in the paper. A single-fed multiband (wideband) planar dipole is combined with cascaded (sandwiched) reflectors made of frequency selective surfaces. Each of those reflectors is placed in a quarter-wavelength distance from the dipole at the frequency of operation. The impedance matching is particularly achieved by active element properties, and impedance symmetrization. Further transformation is made by a planar circuit, placed on the active element plane. The antenna gain is set by the reflector elements amount (reflector plane dimensions). The antenna structure enables its setting into arrays with in-phase feeding

Electrical characterization of capacitively-coupled radio-frequency discharges in hydrogen

This work presents modeling and experimental results for the electrical characterization of capacitively-coupled radio-frequency discharges in hydrogen. A two-dimensional, time-dependent fluid model is used to describe the dynamics of electrons and positive ions H+, H2+, and H3+at different frequencies (13.56–80 MHz), pressures (0.2–1 Torr), and rf applied voltages (50–800 V). The current-voltage relationship is reported and found in good qualitative agreement with experiment. The distribution, between electrons and ions, of the electrical power coupled to the plasma is analyzed. An investigation of the scaling laws for several important plasma parameters is also carried out.Fundação Calouste Gulbenkia

Live Donor Partial Hepatectomy for Liver Transplantation: Is There a Learning Curve?

Background: Donor safety is the first priority in living donor liver transplantation (LDLT). Objective: To determine the characteristics and outcome of live liver donors who underwent donor hepatectomy from January, 1997 to May, 2007 at Massachusetts General Hospital. Methods: 30 patients underwent LDLT between January, 1997 and May, 2007 at our institution. Results: The type of graft was the right lobe (segments 5-8) in 14, left lobe (segments 2-4) in 4, and left lateral sector (segments 2 and 3) in 12 patients. The mean donor age was 36 (range: 26-57) years. The mean follow-up was 48 (range: 18-120) months. No deaths occurred. Overall, 8 (26.6%) patients experienced a total of 14 post-operative complications. Donor complications based on graft type were as follows: left lateral sector (16.7%), left lobe (25%), and right lobe (35.7%). The experience was divided into two periods 1997-2001 (n=15) and 2002-2007 (n=15). Overall complications during 2 periods were 40% and 13.3%, respectively (p<0.001). The incidence of grade III complication also significantly decreased; 66.7% vs 33.3% (p<0.01). Conclusion: Partial hepatectomy in living donors has a learning curve which appears to be approximately 15 cases. This learning curve is not restricted to the surgeons performing the procedure but involves all aspects of patient care

Concordances in Positive Scalar Curvature and Index Theory

We apply the strategy to study of diffeomorphisms via block diffeomorphisms to the world of positive scalar curvature (psc) metrics. For each closed psc manifold, we construct the cubical set of all psc block metrics, the so called concordance set, which only encodes concordance information of psc metrics within its homotopy type. We show that the concordance is a cubical Kan set, give a geometric description for the group structure of the combinatorial homotopy groups, and construct a comparison map from the cubical model of the space of psc metrics on the underlying manifold to the concordance set. Next, we build a concordance-themed model for real K-theory based on the notion of invertible block Dirac operators and use it to factor the index difference through the concordance set. In the final part of this thesis, we construct the psc Hatcher spectral sequence, which is a non-index-theoretic tool to get information about the difference of the space of psc metrics and the concordance set.2023-03-0

Concordances in Positive Scalar Curvature and Index Theory

We apply the strategy to study of diffeomorphisms via block diffeomorphisms to the world of positive scalar curvature (psc) metrics. For each closed psc manifold $M$, we construct the cubical set $\widetilde{\mathcal{R}^{+}_{\bullet}}(M)$ of all psc block metrics, which only encodes concordance information of psc metrics within its homotopy type. We show that $\widetilde{\mathcal{R}^{+}_{\bullet}}(M)$ is a cubical Kan set, give a geometric description for the group structure of the combinatorial homotopy groups, and construct a comparison map from the cubical model $\mathcal{R}^+_{\bullet}(M)$ of the space of psc metrics on $M$ to $\widetilde{\mathcal{R}^{+}_{\bullet}}(M)$. Next, we build a concordance-themed model for real $K$-theory based on the notion of invertible block Dirac operators and use it to factor the index difference through $\widetilde{\mathcal{R}^{+}_{\bullet}}(M)$. In the final part of this thesis, we construct the psc Hatcher spectral sequence, which is a non-index-theoretic tool to get information about the difference of $\mathcal{R}^+_{\bullet}(M)$ and $\widetilde{\mathcal{R}^{+}_{\bullet}}(M)$.Comment: 259 pages, 10 figures, PhD-Thesi

Donor Kidney Recovery Methods and the Incidence of Lymphatic Complications in Kidney Transplant Recipients

Background: Lymphatic leak and lymphocele are well-known complications after kidney transplantation. Objective: To determine the incidence of lymphatic complications in recipients of living donor kidneys. Methods: Among 642 kidney transplants performed between 1999 and 2007, the incidence of lymphatic complications was retrospectively analyzed in recipients of living donor kidneys procured by laparoscopic nephrectomy (LP, n=218) or by open nephrectomy (OP, n=127) and deceased donor kidneys (DD, n=297). A Jackson-Pratt drain was placed in the retroperitoneal space in all recipients and was maintained until the output became less than 30 mL/day. Results: Although the incidence of symptomatic lymphocele, which required therapeutic intervention, was comparable in all groups, the duration of mean±SD drain placement was significantly longer in the LP group—8.6±2.7 days compared to 5.6±1.2 days in the OP group and 5.4±0.7 days in the DD group (p<0.001). Higher output of lymphatic drainage in recipients of LP kidneys could lead to a higher incidence of lymphocele if wound drainage is not provided. Conclusion: More meticulous back table preparation may be required in LP kidneys to decrease lymphatic complications after kidney transplantation. These observations also support the suggestion that the major source of persistent lymphatic drainage following renal transplantation is severed lymphatics of the allograft rather than those of the recipient’s iliac space

Allergologische Diagnostik von Überempfindlichkeitsreaktionen auf Arzneimittel

Drug hypersensitivity reactions have to be tested to identify the culprit substance. The history includes the general information and specific data concerning used drugs, the classification and circumstances of the reaction. Skin tests are performed in all hypersensitivity reactions with allergic symptoms. Tests should be done between four weeks and six months after clearance of the symptoms by performing skin prick test, intradermal test, patch test or photopatch test. Validated tests for the detection of specific IgE antibodies in the serum are available for only few drugs, especially betalactam antibiotics. Other laboratory tests, e.g., the basophil activation test are done only in special cases. Provocation tests are indicated, if the culprit drug cannot be identified by the above mentioned tests. If possible, the evaluation of provocation tests should rely on objective parameters. The concluding assessment will be discussed with the patient and will be documented in an allergy pass