Publications by authors named "Marek Vlk"

Hybrid integration of photonic chips with electronic and micromechanical circuits is projected to bring about miniature, but still highly accurate and reliable, laser spectroscopic sensors for both climate research and industrial applications. However, the sensitivity of chip-scale devices has been limited by immature and lossy photonic waveguides, weak light-analyte interaction, and etalon effects from chip facets and defects. Addressing these challenges, we present a nanophotonic waveguide for methane detection at 3270.

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The increasing incidence of trauma in medicine brings with it new demands on the materials used for the surgical treatment of bone fractures. Titanium, its alloys, and steel are used worldwide in the treatment of skeletal injuries. These metallic materials, although inert, are often removed after the injured bone has healed.

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Nanophotonic waveguides are at the core of a great variety of optical sensors. These structures confine light along defined paths on photonic chips and provide light-matter interaction via an evanescent field. However, waveguides still lag behind free-space optics for sensitivity-critical applications such as trace gas detection.

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Background: Knowledge of the phenotypic pattern of oral squamous epithelium is important in the histopathologic evaluation of lesions including cancer. The literature on normal epithelium is controversial as the phenotype has not been evaluated in samples from completely healthy tissue donors without a history of tobacco and alcohol exposure.

Methods: In this study, we evaluated normal upper lip fornix and gingival mucosa from carefully selected young healthy donors without a history of smoking and alcohol exposure, and keratin types 8, 10, 14, and 17, filaggrin, and Ki67 were investigated in these donors.

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Background: The major limitation of photodynamic therapy with 5-aminolevulinic acid (ALA-PDT) is proper photosensitizer penetration. The nodular form of BCC (nBCC) is perceived as a contraindication to ALA-PDT because the tumor layer is thicker than 2 mm. We have improved on the results of previous studies that used an ablative laser to limit tumor thickness.

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Objective: With proper noninvasive ultrasound measurement of tumor depth, case selection for laser pre-ablation followed by PDT is possible. This combination of methods provides a less invasive approach to the treatment of BCC.

Background Data: Basal cell carcinoma (BCC) primarily affects the face, and, therefore, radical excision is problematic because of the possibility of poor aesthetic outcomes.

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Backgrounds And Objectives: Photodynamic therapy (PDT), via topical aminolevulinic acid (ALA) is an effective treatment for basal cell carcinomas not exceeding a depth of 2 mm. This limits the treatment of basal cell carcinoma (non-melanoma skin cancer) to superficial forms and nodular therapy (only in aesthetically desired locations). This paper addresses the effectiveness of reducing tumor mass via initial Er:YAG laser ablation to depths that are therapeutically responsive to PDT with ALA.

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Aim: To assess the success of genioglossus advancement and hyoid myotomy in the obstructive sleep apnoea syndrome (OSAS) therapy by comparing pre- and postoperative respiratory values during sleep. One of the surgical methods of widening the upper airways is to advance the spina mandibulae together with the genioglossus insertion. Thus the whole tongue is advanced, including its base.

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