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Different instrumentation procedures of the alveolar ridge expansion technique (ARST) with or without Guided Bone Regeneration have proven to be effective for successful implant placement in cases of alveolar bone width between 3mm and 6mm. Conventional bone splitting techniques require flap arising. This technical note demonstrates a method for flapless guided bone splitting. For this purpose, a newly developed surgical guide with internal irrigation channels was used. Using CAD‐CAM additive technology, a narrow slot along the field of interest and a pin of a cooling pipe was designed and implemented in a surgical guide template. The bone split was performed flapless through the surgical guide while the cooling pipe was connected to it. During surgery, the piezo‐driven instrument was moved within that slot, and the irrigation solution was directly rinsing it at point of entry through the irrigation channel. This procedure was performed on a 3.3 mm wide alveolar ridge achieving over 3 mm of bone gain. The described method combines several positive aspects. The micro‐invasive flapless surgical procedure might improve postoperative healing. Additionally, sufficient cooling of the bone might lead to less thermal affection of bone cells and less resorption of the cortical bone. However, systematic studies are needed to confirm the observations of the presented case report., This technical note demonstrates a method for flapless guided bone splitting, for this a newly developed surgical guide with internal irrigation channels was designed.

Objectives The aim of the present clinical study was to determine the stability of color and resistance against abrasion and attrition of provisional single implant restorations. Material and Methods A group of 16 patients were treated with provisional crowns made of Telio CAD. Shortly before the insertion the crowns were photographed and scanned using a 3D‐laser scanner. After 8 weeks of clinical usage, the crowns were photographed and scanned again. The vertical occlusal wear and color changes between the restorations were measured. Results The occlusal plane of the original crown showed a statistically significant reduction of 0.052 mm ± 0.037 mm 8 weeks after placement (p

OBJECTIVES The aim of this study is to analyze the effectiveness of screencast training videos for users from different professional backgrounds on the basis of the quality and quantity of virtual 3D implant planning as evaluated using assessment software. METHODS Participants in the study were dental students (n = 21), dental technicians (n = 16), or practicing dentists (n = 16) with no knowledge of the implant planning software CoDiagnostiX or any experience in virtual implant planning. They were randomly divided into 2 groups: The participants of the control group were presented training videos on CBCT (cone beam computed tomography) and implant planning, additional to the traditional software manual. The participants of the experimental group received, additionally, a training video on the planning software, produced in the form of a screencast. Then 3 implant planning procedures were performed by all participants. The quality of implant planning was assessed using the Treatment Evaluation Tool software, and time for planning was measured. RESULTS Paired sample tests showed significantly shorter planning times for the experimental groups consisting of dentists and students (P < 0.001). A comparison of the results of the individual groups reveals that students and dental technicians who had not received prior screencast training were significantly less precise in their planning (P < 0.001). CONCLUSION This study suggests a promising outcome for the future use of screencasts in the acquisition of software skills for dental software. There is a need for tools for objective self-assessment of effectiveness in software training.

Phylogenetic comparative methods have been used to model trait evolution, to test selection versus neutral hypotheses, to estimate optimal trait-values, and to quantify the rate of adaptation towards these optima. Several authors have proposed algorithms calculating the likelihood for trait evolution models, such as the Ornstein-Uhlenbeck (OU) process, in time proportional to the number of tips in the tree. Combined with gradient-based optimization, these algorithms enable maximum likelihood (ML) inference within seconds, even for trees exceeding 10,000 tips. Despite its useful statistical properties, ML has been criticised for being a point estimator prone to getting stuck in local optima. As an elegant alternative, Bayesian inference explores the entire information in the data and compares it to prior knowledge but, usually, needs much longer time, even on small trees. Here, we propose an approach to use the full potential of ML and Bayesian inference, while keeping the runtime within minutes. Our approach combines (i) a new algorithm for parallel traversal of the lineages in the tree, enabling parallel calculation of the likelihood; (ii) a previously published method for adaptive Metropolis sampling. In principle, the strategy of (i) and (ii) can be applied to any likelihood calculation on a tree which proceeds in a pruning-like fashion, leading to enormous speed improvements. We implement several variants of the parallel algorithm in the form of a generic C++ library, "SPLiTTree", capable to choose automatically the optimal algorithm for a given task and computing platform. We give examples of models of discrete and continuous trait evolution that are amenable to parallel likelihood calculation. As a complete showcase, we implement the phylogenetic Ornstein-Uhlenbeck mixed model (POUMM) in the form of an easy-to-use and highly configurable R-package that calls the library as a back-end. In addition to the above-mentioned usage of comparative methods, POUMM allows to estimate non-heritable variance and phylogenetic heritability. Using SPLiTTree, calculating the POUMM likelihood on a 4-core SIMD-enabled processor is up to 10 times faster than serial implementations written in C and hundreds of times faster than serial implementations written in R. By combining SPLiTTree likelihood calculation with adaptive Metropolis sampling, the time for Bayesian POUMM inference on a tree of ten thousand tips is reduced from several days to a few minutes.

A total of 36 consecutive clinical and two fecal-screening carbapenem-resistant Klebsiella pneumoniae isolates from two Bulgarian university hospitals (Varna and Pleven) were investigated. Susceptibility testing, conjugation experiments, and plasmid replicon typing were carried out. Beta-lactamases were characterized by isoelectric focusing, PCR, and sequencing. Clonal relatedness was investigated by RAPD and multilocus sequence typing (MLST). Most of the isolates demonstrated multidrug resistance profile. Amikacin and tigecycline retained good activity with susceptibility rates of 95 and 87%, respectively. The resistance rate to colistin was 63%. Six RAPD- and MLST-types were identified: the dominating MLST-type was ST15 (27 isolates), followed by ST76 (six isolates), and ST1350 (two isolates). ST101, ST258, and ST151 were detected once. All except one of the K. pneumoniae produced KPC-2, mostly in combination with CTX-M-15, while for one isolate (ST101) the enzymes OXA-48 and CTX-M-14 were found. All KPC-2-producing transconjugants revealed the presence of IncFII plasmid. The OXA-48- and CTX-M-14-producing isolate showed the presence of L/M replicon type. The dissemination of KPC-2-producing K.pneumoniae in Bulgaria is mainly due to the sustained spread of successful ST15 clone and to a lesser extent of ST76 clone. This is the first report of OXA-48 producing ST101 K. pneumoniae in Bulgaria.

The commonly used parameters characterizing fuel cells and in particular microbial fuel cells (MFCs) electrical performance are open circuit voltage (OCV), maximum power, and short circuit current. These characteristics are usually obtained from polarization and power curves. In the present study, the expanded uncertainties of operational characteristics for yeast-based fuel cell were evaluated and the main sources of uncertainty were determined. Two approaches were used: the uncertainty budget building for sources uncertainty estimation and a statistical treatment of identical MFCs results – for operational characteristics uncertainty calculation. It was found that in this particular bioelectrochemical system the major factor contributing to operational characteristics uncertainties was the electrodes' resistance. The operational characteristics uncertainties were decreased from 19 to 13% for OCV, from 42 to 14% for maximal power, and from 46 to 13% for short circuit current with the usage of electrodes with resistance in the interval 6–7 Ω. The described approaches can be used for operational characteristics expanded uncertainties calculation of all types of fuel cells using data from polarization measurements.

In this paper, we report for the first time that Candida melibiosica 2491 yeast strain expresses enhanced phytase activity when used as a biocatalyst in biofuel cells. The polarization also results in an increase of the yeast biomass. Higher steady-state electrical outputs, assigned to earlier production of an endogenous mediator, were achieved at continuous polarization under constant load. The obtained results prove that the C. melibiosica yeast-based biofuel cell could be used for simultaneous electricity generation and phytate bioremediation. In addition, the higher phytase activity obtained by interruptive polarization suggests a new method for increasing the phytase yield from microorganisms. Copyright © 2014 John Wiley & Sons, Ltd.

Our objective was to investigate the plasmid replicon-types involved in spread of ESBLs among Bulgarian Klebsiella pneumoniae and Escherichia coli. Sixty-three isolates, with transferable beta-lactam resistance determinants, collected between 2007 and 2009 in six medical institutions, were analysed with respect to their antimicrobial susceptibility, ESBL-, RAPD-, and plasmid replicon-type. Phylogenetic typing and screening for the O25b-ST131 lineage were carried out for E. coli. The predominant ESBLs were CTX-M-15 (81%) among E. coli and CTX-M-3 (58%) among K. pneumoniae. Other sporadically found ESBLs were SHV-12 and TEM-139, and for the first time in Bulgaria, CTX-M-1 and CTX-M-14. Replicon typing revealed that plasmids carrying blaCTX-M-3 exclusively belonged to IncL/M-type, while blaCTX-M-15 was predominantly (94%) associated with IncF-type plasmids. Among E. coli, 59% of the isolates were clonally related. Isolates of that cluster produced CTX-M-15, belonged to the O25b-ST131 lineage, predominantly harboured plasmids with the FIA replicon, and were found in five centres. Among CTX-M-3-producing K. pneumoniae, two prevailing RAPD-types were found, one remained restricted to one centre and the second was found in three centres. The incompatibility groups IncN and IncA/C linked with blaSHV-12 respectively blaTEM-139 were found only once. To the best of our knowledge, this is the first detailed investigation of plasmids carrying ESBL genes among Bulgarian isolates demonstrating wide distribution of conjugative IncF plasmids among CTX-M-15-producing E. coli and IncL/M plasmids among CTX-M-3 positive K. pneumoniae isolates.

The paper reports results from Langmuir probe current-voltage (IV) characteristic measurements in argon and oxygen low-gas-pressure magnetized plasma. The plasma was produced in a stainless steel discharge tube with length 1.5 m and diameter 0.17 m with a hot filaments cathode. The wall of the discharge tube was grounded. An axial magnetic field B was created by a solenoid. A platinum cylindrical Langmuir probe with radius R = 5· 10−5 m and length L = 5· 10−3 m was placed axially and radially at the center of the discharge tube in order to perform measurements along and across the magnetic field. Using the second derivatives of the measured IV probe characteristics, the EEDF in argon and oxygen was evaluated. The derivatives were taken numerically. Measurements in an argon (i.e., in the absence of negative ions) were performed to obtain results for comparison with the measurements in an oxygen gas discharge, where a high density of negative ions is expected. In the measurements of the second derivatives of the IV characteristics with the probe parallel to the magnetic field in oxygen, a peak appears close to the plasma potential due to the registration of negative ions. In the same time, the electron part of the second derivative was substantially suppressed relatively to the case with the probe oriented perpendicular to the magnetic field. Thus using the appropriate orientation of the probe and a low magnetic field, when the electron part of the second derivative is suppressed, since the negative ion part is not affected by the low magnetic field applied, we can evaluate precisely the negative ion density. The results from the plasma parameters evaluation (plasma potential, electron and negative ion densities and electron temperatures) are presented and discussed (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Ouzounova-Raykova V, Jordanov D, El-Tibi M, Mitov I. Gonococcal infection in symptomatic and asymptomatic persons seeking medical clinics in Sofia. A 3-year study 2008–2010. APMIS 2011; 119: 864–7. The aim was to determine the prevalence of gonococcal infection and to compare the results with those received by other researchers, because in Bulgaria a good medical practice for the laboratory confirmation, report and therapy is lacking. A total of 617 specimens from symptomatic and asymptomatic persons attending clinics in Sofia from January 2008 to December 2010 were tested by culture and in-house PCR. Using PCR Neisseria gonorrhoeae was identified in six urethral (6.25%) and eight (1.54%) cervical specimens. By applying culture method, N. gonorrhoeae positive result was found in 12 swabs – one cervical and one urethral swab less. The positive results correspond predominantly to persons with genital complains and suspicions for gonococcal or other sexually transmitted infection. This is the first study in Bulgaria since 1989 and determines the prevalence of N. gonorrhoeae to 2.3% over a 3-year period. Detection by culture was slightly less sensitive than by nucleic acid amplification test (NAAT). Continuous monitoring of gonorrhea by culture and NAAT is important for public health in Bulgaria.

doi: 10.1111/j.1741-2358.2010.00409.x Dental care and treatment needs of elderly in nursing homes in Saarland: perceptions of the homes managers Objective: To investigate nursing home managers’ perceptions and attitudes towards oral health care and access to dental services for aged care facility residents. Method: Questionnaires containing 28 closed-ended questions were mailed to all 114 nursing homes in Saarland, Germany. Descriptive statistics were calculated for response items. Results: Facility response rate was 39%. None of the nursing homes in this study offered systematic dental health care. Initial dental screening was carried out only in one facility. In 81%, dental examinations only took place if required. Although stationary dental equipment was available only in one home, dental treatment was carried out in 71% of the cases by a dentist in the nursing home. Eighty-four per cent of the homes’ managements rated the state of the dentition of the inhabitants as satisfying. Over half of the managers indicated satisfaction with the know-how of their nursing staff concerning oral hygiene procedures. The most significant barriers to provision of dental care in the facilities according to their managers were staff shortage, lack of interest of the inhabitants and financial concerns. Conclusions: The results of this study showed an urgent need for estimating a programme for systematic dental care for institutionalised elder people in the federal state of Saarland.

GelBandFitter is a computer program that uses non-linear regression techniques to fit mathematical functions to densitometry profiles of protein gels. This allows for improved quantification of gels with partially overlapping and potentially asymmetric protein bands. The program can also be used to analyze immunoblots with closely spaced bands. GelBandFitter was developed in Matlab and the source code and/or a Windows executable file can be downloaded at no cost to academic users from http://www.gelbandfitter.org.

Scientists aspire to understand the underlying physics behind the formation of instabilities in soft matter and how to manipulate them for diverse investigations, while engineers aim to design materials that inhibit or impede the nucleation and growth of these instabilities in critical applications. The present paper reviews the field-induced rotational instabilities which may occur in chiral smectic liquid-crystalline layers when subjected to an asymmetric electric field. Such instabilities destroy the so-named bookshelf geometry (in which the smectic layers are normal to the cell surfaces) and have a detrimental effect on all applications of ferroelectric liquid crystals as optical materials. The transformation of the bookshelf geometry into horizontal chevron structures (in which each layer is in a V-shaped structure), and the reorientation dynamics of these chevrons, are discussed in details with respect to the electric field conditions, the material properties and the boundary conditions. Particular attention is given to the polymer-stabilisation of smectic phases as a way to forbid the occurrence of instabilities and the decline of related electro-optical performances. It is also shown which benefit may be gained from layer instabilities to enhance the alignment of the liquid-crystalline geometry in practical devices, such as optical recording by ferroelectric liquid crystals. Finally, the theoretical background of layer instabilities is given and discussed in relation to the experimental data.

Membranes based on sulfonated arylene polymers and their cross-linked blends were prepared. embedding the ionomers into textile or porous ptfe matrix and/or doping with zrp nanoparticles reduced the swelling, and improved the thermal stability. ptfe reinforcement led to an excellent single cell performance, which is promising for pemfc applications. some of the membranes performed better than nafion(r). the net methanol crossover correlates with the membranae thickness and composition, but surprisingly, suppression of the methanol crossover alone, does not enhance u/i performance. esr experiments of oxidative degradation of the monomer by oh center dot at ph > 10 leads to phenoxyl and semi-quinone radicals. this study focuses on the case where o-2(center dot-) or o-1(2) are the damaging species, i.e. above ph 11.7, and the dominant reaction is that involving the aromatic ring. under conditions of fuel starvation, the acid protons get depleted, which may lead to high local ph values, even in an overall acidic environment. it is therefore important to be aware of the entirely different form of degradation chemistry at high ph. in the presence of both ho center dot radicals and oxygen, complete degradation of the aromatic rings can be observed, within hours. in view of this, perfluorinated membranes are more inert. cross-linked arylene polymer blend membranes and ptfe-reinforced arylene ionomer membranes can be regarded as promising for further development, due to their high stability and excellent pemfc performance.

To predict hydroxyl-radical-initiated degradation of new proton-conducting polymer membranes based on sulfonated polyetherketones (PEK) and polysulfones (PSU), three nonfluorinated aromatics are chosen as model compounds for EPR experiments, aiming at the identification of products of HO.-radical reactions with these monomers. Photolysis of H2O2 was chosen as the source of HO. radicals. To distinguish HO.-radical attack from direct photolysis of the monomers, experiments were carried out in the presence and absence of H2O2. A detailed investigation of the pH dependence was performed for 4,4′-sulfonylbis[phenol] (SBP), bisphenol A (= 4,4′-isopropylidenebis[phenol]; BPA), and [1,1′-biphenyl]-4,4′-diol (BPD). At pH ≥ pKA of HO. and H2O2, reactions between the model compounds and O2.− or 1O2 are the most probable ways to the phenoxy and ‘semiquinone’ radicals observed in this pH range in our EPR spectra. A large number of new radicals give evidence of multiple hydroxylation of the aromatic rings. Investigations at low pH are particularly relevant for understanding degradation in polymer-electrolyte fuel cells (PEFCs). However, the chemistry depends strongly on pH, a fact that is highly significant in view of possible pH inhomogeneities in fuel cells at high currents. It is shown that also direct photolysis of the monomers leads to ‘semiquinone’-type radicals. For SBP and BPA, this involves cleavage of a CC bond.

Three different electron beam irradiated fluoropolymers (ETFE, FEP, and PVDF) as well as their grafting reactions with styrene in different diluents were investigated by means of electron spin resonance (ESR). Depending on the atmosphere during irradiation, ESR spectra of peroxy and alkyl radicals were observed. Radical decay as a function of time and temperature was investigated in the presence and absence of solvent. Grafting levels and number of monomer units per chain were calculated for both types of radicals. Irradiation atmosphere, grafting temperature, and added solvent affect the morphology of the fluoropolymers, in particular the crystalline versus amorphous fractions and their swelling. They thus influence the rate at which the initial radicals at the polymer backbone are reached during the grafting process. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3323–3336, 2006

A comparative study on the kinetics and mechanism of mechanochemical activation (by high energy grinding) of magnetite (Fe 3 0 4 ) and maghemite (γ-Fe 2 O 3 ) has been carried out. It has been established that during the activation the crystal lattice is distorted and phase and structure transformations occur. The phase compositions of intermediate and final products are registered by Mossbauer spectroscopy and X-ray analysis. It was found that the end product of mechanochemical activation of Fe 3 O 4 and γ-Fe 2 O 3 is highly dispersed hematite. The kinetics of phase changes are determined for the two iron oxides which are characterized by different valency states and cation distributions in the spinel lattice. The different rates of phase transformations have been explained by a phonon mechanism of energy dissipation for maghemite and a mixed phonon-electron mechanism for magnetite.

The preparation and catalytic properties of mixed Fe–Mo–W catalyst toward methanol oxidation are investigated. Mossbauer spectroscopy, X-ray diffraction and chemical studies revealed the formation of two types of solid solutions with compositions Fe 2 (Mo x W 1− x O 4 ) 3 and (Mo x W 1− x )O 3 . The solid solutions formed are characterized by high activity and selectivity upon methanol oxidation and are of interest in view of their practical application.