The foetal development of the human osseous labyrinth in a computed tomographic study

A CT study was performed on 8 foetuses aged between 20 and 38 weeks. In foetuses at the 20th week the semicircular canals, the spiral canal of the cochlea and the initial (labyrinthine) part of the facial canal are visible. At week 24 the tympanic part of the facial canal is observed. In the 31st week the cochlea is divided into 2 compartments, and in the 38th week the vestibular aqueduct and osseous labyrinth are seen

Identification of Sulfate Sources and Biogeochemical Processes in an Aquifer Affected by Peatland: Insights from Monitoring the Isotopic Composition of Groundwater Sulfate in Kampinos National Park, Poland

Temporal and spatial variations of the concentration and the isotopic composition of groundwater sulfate in an unconfined sandy aquifer covered by peatland have been studied to better understand the sources and biogeochemical processes that affect sulfate distribution in shallow groundwater systems influenced by organic rich sediments. The groundwater monitoring was carried out for one year at hydrogeological station Pożary located within the protected zone of the Kampinos National Park. Sulfur (δ34SSO4) and oxygen (δ18OSO4) isotopic composition of dissolved sulfates were analyzed together with oxygen (δ18OH2O) and hydrogen (δ2HH2O) isotopic composition of water and major ions concentration at monthly intervals. The research revealed three main sources of sulfates dissolved in groundwater, namely, (a) atmospheric sulfates—supplied to the aquifer by atmospheric deposition (rain and snow melt), (b) sulfates formed by dissolution of evaporite sulfate minerals, mainly gypsum—considerably enriched in 34S and 18O, and (c) sulfate formed during oxidation of reduced inorganic sulfur compounds (RIS), mainly pyrite—depleted in 34S and 18O. The final isotopic composition and concentration of dissolved SO42− in groundwater are the result of overlapping processes of dissimilatory sulfate reduction, oxidation of sulfide minerals, and mixing of water in aquifer profile

Problems in “age” dating of groundwater drained by the Pieniny springs

W artykule zaprezentowano wyniki oznaczeń trytu w wodach z czterech źródeł usytuowanych na terenie Pienińskiego Par¬ku Narodowego. Za pomocą programu FLOWPC podjęto próbę oszacowania trytowego wieku wód w systemie hydrogeologicznym, tj. czasu wymiany wody w zbiornikach drenowanych przez źródła. Z uwagi na skomplikowany porowo-szczelinowy system krążenia wód i niewielkie obszary zasilania najbardziej prawdopodobne wyniki uzyskuje się dla modeli dyspersyjnych i eksponencjalno-tłokowych. Uzyskane wyniki szacowania wieku wód, niezależnie od przyjętego modelu i jego parametrów, potwierdzają stosunkowo młody wiek wód, nieprzekraczający najprawdopodobniej 30 lat, i świadczą o drenowaniu przez badane źródła wód współczesnego zasilania infiltracyjnego.The paper presents the results of tritium determinations in four springs located within the Pieniny National Park. The attempt of assessing the age of groundwater, i.e. the groundwater tritium turnover time in the drained reservoirs was made using the FLOWPC computer code application. Due to the complex fissure-pore groundwater circulation system as well as relatively small recharge areas, the most reliable results were obtained for dispersion and exponential-piston flow models. The obtained groundwater age estimations, regar¬dless of the assumed model and its parameters, corroborated the relatively young age of studied waters, presumably not exceeding 30 years. This proves that the studied springs in the Pieniny National Park are recharged mainly by modern infiltration

Thermal and Mineral WatersOrigin, Properties and Applications /

XV, 135 p. 85 illus., 49 illus. in color.online r

Direct round window stimulation with the Med-El Vibrant Soundbridge: 5 years of experience using a technique without interposed fascia

The objective of this study was to present 5 years of surgical experience, and the extended results of hearing preservation (based on 3-year follow-up), with the Med-El Vibrant Soundbridge (VSB) in which the floating mass transducer (FMT) is placed directly against the round window membrane, and the fascia is used only as covering tissue to keep it in position. A retrospective survey of surgical and audiological data was conducted to evaluate the performance and stability of patient hearing, with audiometric measurements performed over fixed time intervals up to 36 months. 21 patients, aged 19–62 years (mean 48.4), with mixed or conductive, bilateral or unilateral hearing loss were included in this study. Surgical intervention involved monaural implantation of the Med-El VSB between 2006 and 2009. The results were assessed using pure tone audiometry. In 5 years of experience with the technique, no significant complications or device extrusion were observed except for two revision surgeries requiring FMT repositioning. In the 3-year follow-up, we observed stable hearing in the implanted ear. It is concluded that direct round window stimulation without interposed fascia is an alternative for patients with hearing impairment caused by chronic otitis media and/or lack of ossicles, especially after modified radical mastoidectomy. It allows good results in a selected group of patients, although further observation on a larger population is needed to confirm long-term validity and effectiveness