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Introduction: Odontogenic inflammation is a fairly common condition, and depends on the quality of oral health. Unfortunately, the incidence in the Czech population is increasing. It is also sometimes connected with life-threatening complications. Aim: To describe an unusual method of treating phlegmonous inflammation of the mouth floor and neck, complicated by necrotizing fasciitis.Material and Method, Results: The authors demonstrate a strategy of treating odentogennic phlegmonous inflammation of the mouth floor in a patient with a blood coagulation disorder and advanced liver cirrhosis. The course of treatment was complicated by a massive gastric ulcer bleeding and due to the large necrosis of the soft tissue of the neck. Application of local negative pressure was used successfully. Conclusion: The local application of negative pressure in the surgical treatment of necrotizing fasciitis in the head and neck region is not very common. Recently, a number of authors have described the feasibility of this procedure in this anatomical location. The main advantages are, among others, shorter and less costly treatment and reduced stress for medical staff.

While the importance of anaerobic methane oxidation has been reported for marine ecosystems, the role of this process in soils is still questionable. Grasslands used as pastures for cattle overwintering show an increase in anaerobic soil micro-sites caused by animal treading and excrement deposition. Therefore, anaerobic potential methane oxidation activity of severely impacted soil from a cattle winter pasture was investigated in an incubation experiment under anaerobic conditions using 13C-labelled methane. We were able to detect a high microbial activity utilizing CH4 as nutrient source shown by the respiration of 13CO2. Measurements of possible terminal electron acceptors for anaerobic oxidation of methane were carried out. Soil sulfate concentrations were too low to explain the oxidation of the amount of methane added, but enough nitrate and iron(III) were detected. However, only nitrate was consumed during the experiment. 13C-PLFA analyses clearly showed the utilization of CH4 as nutrient source mainly by organisms harbouring 16:1ω7 PLFAs. These lipids were also found as most 13C-enriched fatty acids by Raghoebarsing et al. (2006) after addition of 13CH4 to an enrichment culture coupling denitrification of nitrate to anaerobic oxidation of methane. This might be an indication for anaerobic oxidation of methane by relatives of "Candidatus Methylomirabilis oxyfera" in the investigated grassland soil under the conditions of the incubation experiment.

Short-term diurnal changes in emissions of CO2 and N2O were determined in a cattle overwintering area during three specific periods of the year. Production of both N2O and CO2, as determined with gas chambers buried in soil and spatially distributed changed rapidly, and the general course of fluxes of the two gases was different. CO2 emissions were basically controlled by temperature, and most gas chambers showed the same trends in CO2 flux, indicating low spatial heterogeneity. In contrast, N2O emissions were much more spatially heterogeneous and each chamber had its own time course of emission; therefore, the relationship between flux and temperature was more complicated for N2O than CO2. For estimating gas emissions over long periods, we strongly recommend the use of frequent emission measurements during periods of high gas fluxes.

This paper presents a work in progress on experiments with embedded operating systems for the MicroBlaze processor. Modern embedded systems based on a configurable platform incorporating a similar processor core are gaining importance with the ongoing effort to minimize cost and development time. After an overview of the configurable platform based on this processor core, we devote our attention to uClinux OS. This OS has been successfully ported for the MicroBlaze processor, and we present our current experience with it. At the end of the paper we discuss several possible booting strategies and recommend further development of U-BOOT.

This paper deals with the distance estimation issue in 802.15.4 wireless sensor networks. On a basis of signal strength of received frames a distance between two sensor nodes using the log-normal shadowing radio propagation model (LNSM) is estimated. Basic problems of signal strength based systems are variation of RSSI parameter and correct calibration of coefficients for the LNSM model. For distance estimation in wireless networks, static and dynamic methods of calibration were already introduced. Static calibration has significant drawback in adaptation to the dynamical environment changes. Proposed work deals with an experimental validation of dynamic calibration method for distance estimation in wireless sensor networks. This method for dynamic estimation of radio environment parameters results in the significant improvements in the distance estimation accuracy in comparison with the known static methods.

All known localization techniques for wireless sensor and ad-hoc networks require certain set of reference nodes being used for position estimation. The anchor-free techniques in contrast to anchor-based do not require reference nodes called anchors to be placed in the network area before localization operation itself, but they can establish own reference coordinate system to be used for the relative position estimation. We observed that contemporary anchor-free localization algorithms achieve a low localization error, but dissipate significant energy reserves during the recognition of reference nodes used for the position estimation. Therefore, we have proposed the optimized anchor-free localization algorithm referred to as BRL (Boundary Recognition aided Localization), which achieves a low localization error and mainly reduces the communication cost of the reference nodes recognition phase. The proposed BRL algorithm was investigated throughout the extensive simulations on the database of networks with the different number of nodes and densities and was compared in terms of communication cost and localization error with the known related algorithms such as AFL and CRP. Through the extensive simulations we have observed network conditions where novel BRL algorithm excels in comparison with the state of art.

This paper presents the investigation of energy demands during localization of wireless nodes in ad-hoc networks. We focus on the method based on the received signal strength (RSS) to estimate the distances between the nodes. To deal with the uncertainty of this technique, statistical methods are used. It implies more measurement samples to be taken and consequently more energy to be spent. Therefore, we investigate the accuracy of localization and the consumed energy in the relation to the number of measurement samples. The experimental measurements were conducted with IRIS sensor motes and their results related to the proposed energy model. The results show that the expended energy is not related linearly to the localization error. First, improvement of the accuracy rises fast with more measurement samples. Then, adding more samples, the accuracy increase is moderate, which means that the marginal energy cost of the additional improvement is higher.

A numerical 0D kinetic model is developed here to simulate the detailed kinetics of the ground and excited electronic states of atmospheric gases occurring under streamer discharge conditions. The model is based on an extended kinetic scheme that involves state-to-state vibrational kinetics of the ground electronic states of N2, O2 and NO diatomics, including e–V, V–V and V–T energy transfers, and contains about 104 processes for more than 500 tracked state-specific states (including the higher excited and autoionising states of NI/OI atomic species), and also for state-non-specific species. This scheme takes into account the most important radiative processes occurring in N2 and N2–O2 mixtures that are of diagnostic interest, including the extreme ultraviolet and vacuum ultraviolet radiation produced by many excited and autoionising states of NI/OI. The dependence of the rates of electron-impact processes on the reduced electric field E/N is found by solving the Boltzmann equation for electrons in the two-term approximation using the Boltzmann equation solver Open Source library, BOLOS. We examine several test cases: pure nitrogen at 50 and 200 Torr and synthetic air at 10, 50 and 760 Torr, at a gas temperature of 300 K. The numerical results for pure nitrogen were compared with experimental results recently obtained by laser induced fluorescence for metastables. Good qualitative agreement was observed between numerical simulations and experiments at vibronic levels v  =  2–5, giving important feedback on the appropriateness of the kinetic scheme. Numerical results were also used to find several general spectrometric signatures that might be helpful in the development of diagnostic procedures. [ABSTRACT FROM AUTHOR]

Time-resolved microscopic ICCD images, emission waveforms and spectra of triggered single-surface coplanar dielectric barrier micro-discharges were acquired with nanosecond time resolution. The micro-discharges were produced in pure argon by applying periodic high-voltage waveforms to a pair of embedded metallic electrodes at atmospheric pressure, and microscopic images of single micro-discharge events complemented with spectrally resolved emission were acquired with a time resolution of a few nanoseconds. Due to the low jitter of the micro-discharge onset with respect to the high-voltage pulse, we succeeded in separating the very weak emission produced during the course of streamer formation from the emission produced during the transition between the streamer and the subsequent transient glow phase. We identified the characteristic spectrometric signatures of the transition between the streamer and glow phases by analysing the lines belonging to the Ar(3s23p54p → 3s23p54s) multiplet. By linking optical and electrical measurements, we estimated the electron density with a high temporal resolution. The electron densities of the streamer discharge, determined spectroscopically, were in the range of 1019–1020 m−3, while an estimate of 1021 m−3 was obtained using macroscopic electrical analysis combined with ICCD imaging. The evolution of selected population ratios of 2p levels during streamer evolution was determined for the first time, and this may be used in the future for advanced streamer diagnostics. [ABSTRACT FROM AUTHOR]

The formation of N2(A3 ) metastable species, produced by cathode-directed streamer discharge, was investigated using the technique of laser-induced fluorescence. A triggered single streamer filament was periodically produced in pure nitrogen (and in nitrogen with admixtures of oxygen) at total pressure of 50 Torr and metastable species were monitored during the streamer channel decay in the centre of the discharge gap. We revealed the dynamics of individual vibrational (v  =  0–8) levels of N2(A3 ) for various oxygen admixtures (0–20%). In pure nitrogen, the observed evolution of the N2(A3 ) during the decaying streamer channel is evidence of initial vibrational relaxation of high vibrational levels towards the v  =  2 and 3 levels, followed by a delayed increase of terminal (v  =  0, 1) levels. A calibration procedure based on the rate of energy-pooling processes was used to place all detected vibronic levels in pure nitrogen on the absolute scale. Population maxima exceeding 1  ×  1014 cm−3 were fixed for the v  =  2 and 3 vibrational levels, while the lowest v  =  0 level reaches only 3  ×  1013 cm−3. Populations of v  =  2–5 vibrational levels were also estimated for N2  +  O2 mixtures after scaling of laser-induced fluorescence signals obtained at various oxygen admixtures. The total N2(A3 ) population in an air-like mixture is formed mainly by v  =  3–4 vibronic levels with the population maximum of ~3  ×  1013 cm−3 fixed at the shortest analyzed delay. This observation, together with the fact that we were unable to detect v  =  0 and 1 levels (fluorescence signals below detection threshold), gives a strong evidence of the inhibition of Δv  =  2 vibrational relaxation towards terminal v  =  0 and 1 levels, causing much lower populations of the lowest v  =  0–1 levels. By analyzing data obtained in pure nitrogen and in nitrogen with three different oxygen admixtures, we have estimated the quenching rate constants of N2(A3 , v)  +  O2 and N2(A3 , v)  +  N2 processes for v  =  2–6 vibrational levels which are consistent with data from the literature. Quenching rate constants for nitrogen reflect the N2(A3 , v)  →  N2(A3 , v  −  2) relaxation process, however the v  =  2 rate constant shows a much larger value compared with the published data. [ABSTRACT FROM AUTHOR]

Many studies proved that non-equilibrium discharges generated at atmospheric pressure are highly effective for the bio-decontamination of surfaces of various materials. One of the key processes that leads to a desired result is plasma etching and thus the evaluation of etching rates of organic materials is of high importance. However, the comparison of reported results is rather difficult if impossible as different authors use diverse sources of atmospheric plasma that are operated at significantly different operational parameters. Therefore, we report here on the systematic study of the etching of nine different common polymers that mimic the different structures of more complicated biological systems, bovine serum albumin (BSA) selected as the model protein and spores of Bacillus subtilis taken as a representative of highly resistant micro-organisms. The treatment of these materials was performed by means of atmospheric pressure dielectric barrier discharge (DBD) sustained in open air at constant conditions. All tested polymers, BSA and spores, were readily etched by DBD plasma. However, the measured etching rates were found to be dependent on the chemical structure of treated materials, namely on the presence of oxygen in the structure of polymers. [ABSTRACT FROM AUTHOR]

The initial stages of transient luminous events (TLEs) occurring in the upper atmosphere of the Earth are, in a certain pressure range, controlled by the streamer mechanism. This paper presents the results of the first laboratory experiments to study the TLE streamer phenomena under conditions close to those of the upper atmosphere. Spectrally and highly spatiotemporally resolved emissions originating from radiative states (second positive system) and (first negative system) have been recorded from the positive streamer discharge. Periodic ionizing events were generated in a barrier discharge arrangement at a pressure of 4 torr of synthetic air, i.e. simulating the pressure conditions at altitudes of ≃37 km. Employing Abel inversion on the radially scanned streamer emission and a 2D fitting procedure, access was obtained to the local spectral signatures within the over 106  m s−1 fast propagating streamers. The reduced electric field strength distribution within the streamer head was determined from the ratio of the band intensities with peak values up to 500 Td and overall duration of about 10 ns. The 2D profiles of the streamer head electric fields were used as an experimentally obtained input for kinetic simulations of the streamer-induced air plasma chemistry. The radial and temporal computed distribution of the ground vibrational levels of the radiative states involved in the radiative transitions analyzed (337.1 nm and 391.5 nm), atomic oxygen, nitrogen, nitric oxide and ozone concentrations are vizualized and discussed in comparison with available models of the streamer phase of Blue Jet discharges in the stratosphere. [ABSTRACT FROM AUTHOR]

Introduction and aim: Dental models are widely used in dentistry. The transmission of oral cavity situation outside patient's mouth brings us information in the field of diagnostics, treatment planning, and the fabrication planning of dental products. Dental models can be used in any dental field. They are particularly linked to prosthodontics, orthodontics, and maxillofacial surgery. The aim of this article is to report the benefits of the intraoral scanning in conjuction with 3D printing to the reader. Also, it describes their basic principles and presents the most useful technologies of 3D printing for production in dentistry according to the current literature. Materials and methods: The literature search and survey were focused on intraoral scanning and 3D printing. PubMed, Scopus, and Ebsco databases were used to find the articles. Their applicability in dentistry, the inclusion of a control group, and the age of the article within five years were essential for their subsequent selection. Conclusion: The included studies show that the technologies of direct intraoral scanning and 3D printing are already clinically usable today, and in the future we can expect their further development for everyday practice.

The evolution of individual v = 0–10 vibrational levels of N2(A3) metastable species produced by filamentary streamer discharge was investigated by the laser-induced fluorescence technique. Triggered single streamer filament was periodically produced in pure nitrogen at a pressure of 200 torr and metastable species were monitored during the streamer channel decay in the centre of the discharge gap. The observed dynamics of N2(A3) vibrational levels follow two very different scenarios: while higher (v  >  6) vibronic levels decay exponentially in hundreds of nanoseconds, the populations of lower levels (v  ≤  6) definitely increase, first reaching a local maximum on a microsecond timescale and then decreasing afterwards. Population maxima of N2(A3, v  ≤  6) levels occur after the streamer onset with a certain delay, which decreases with increasing vibrational number. Interpretation of experimental observation based on a 0D kinetic model of the post-discharge period takes into account the most important processes redistributing populations between the N2(A3), N2 and N2 vibronic levels. The model reproduces experimental observations fairly well, including observed maxima delays occurring due to the collisional cascade, which transfers metastable species from higher even/odd vibrational levels towards v = 0/v = 1 terminal levels through the Δv = 2 vibrational relaxation mechanism. A calibration procedure based on the rate of energy-pooling processes was used to determine absolute populations of the v = 0 and 1 levels from LIF data, and the model results were utilized to place on an absolute scale all the higher (v  >  1) measured vibronic levels. Vibrational distributions obtained from calibrated LIF data at selected instants show a reasonable qualitative agreement with model predictions. Population maxima exceeding 3   ×   1014 cm−3 were fixed for v = 2 and 3 vibrational levels, while the lowest v = 0 level reaches only 8–9   ×   1013 cm−3. Lastly, we show that the observed rate of the v = 2 level decay is not compatible with published rate constants for the v = 2  →  v = 0 vibrational relaxation. [ABSTRACT FROM AUTHOR]

This paper reviews optical diagnostic methods and approaches applied to study the fundamentals of streamer discharges, considering the peculiarities of streamers developing in atmospheric gases at high (1 bar) as well as low (<10 mbar) pressures. A critical discussion is devoted to the cross-sections for electron-impact excitation/ionization/dissociation processes and corresponding rate constants in relation to methods used to probe streamer properties. The most important spectrometric signatures of radiative transitions of diatomic as well as atomic species are discussed on the basis of their synthetic models with a brief guide on how to simulate the most important emissions. Basic differences between UV–vis–NIR spectra produced by electron-impact and various heavy-particle energy-transfer processes during streamer evolution are presented and possible strategies based on 2D projections of cylindrically symmetric streamers to determine radial distributions of excited species within the streamer channel are discussed. The use of emission techniques to obtain the rotational temperatures and vibrational distributions of excited states of diatomics and laser-induced fluorescence techniques to probe the vibrational manifold of the lowest triplet metastable state of the nitrogen molecule is addressed. [ABSTRACT FROM AUTHOR]