423 research outputs found
Endovenous laser ablation: the role of intraluminal blood
AbstractObjectiveIn this histological study, the role of the intraluminal blood during endovenous laser ablation was assessed.MethodsIn 12 goats, 24 lateral saphenous veins were treated with a 1500-nm diode laser. Four goats were treated in an anti-Trendelenburg position (group 1). The next four goats were treated in a Trendelenburg position (group 2) and the remaining four goats in the Trendelenburg position with additional injection of tumescent liquid (group 3). Postoperatively, the veins were removed after 1 week and sent for histological examination. We measured the number of perforations. Vein wall necrosis and the perivenous tissue destruction were quantified using a graded scale.ResultsThe ‘calculated total vein wall destruction’ was significantly higher in the third group (81.83%), as compared with groups one (61.25%) (p < 0.001) and two (65.92%) (p < 0.001). All three groups showed a significant difference in the perivenous tissue destruction scale (p < 0.001) with the lowest score occurring in the third group. Vein wall perforations were significantly more frequent in groups one and two as compared with the third group (T-test respectively p < 0.001, p = 0.02).ConclusionA higher intraluminal blood volume results in reduced total vein wall destruction. Injection of tumescent liquid prevents the perivenous tissue destruction and minimises the number of perforations
Antiviral activity of synthetic aminopyrrolic carbohydrate binding agents: targeting the glycans of viral gp120 to inhibit HIV entry
An experience in modelling business process architecture
We present a mapping of a previously designed Business Process
Architecture (BPA) meta-model onto ArchiMate, i.e., the de facto standard
Enterprise Architecture (EA) modelling language. This construct mapping allows
developing process maps, i.e., descriptions of (views of) the business process
architecture of an organization. We demonstrate the development of these process maps using the Signavio Business Process Management (BPM) modelling
platform. The developed process maps are part of the organization’s enterprise
architecture model and are linked to BPMN process diagrams that detail the
functional, control-flow, data and resource aspects of the business processes
included in the process map. Our research contributes to the integration of BPM
and EA by researching BPA as a concept common to both disciplines
All optical wavelength conversion via cross phase modulation in chalcogenide glass rib waveguides
We demonstrate all-optical wavelength conversion in a 5 cm
As2S3 chalcogenide glass rib waveguide with 5.4 ps pulses over a
wavelength range of 10 nm near 1550 nm. We present frequency resolved
optical gating (FROG) measurements that show good converted pulse
integrity in terms of amplitude and phase in the frequency and time
domains. The short interaction length ensures that dispersion induced walkoff
does not hinder the conversion range of the device
Three-Terminal Junctions operating as mixers, frequency doublers and detectors: A broad-band frequency numerical and experimental study at room temperature
The frequency response of nanometric T- and Y-shaped three-terminal junctions (TTJs) is investigated experimentally and numerically. In virtue of the parabolic down-bending of the output voltage of the central branch obtained at room temperature under a push-pull fashion input, we analyze: the low-frequency performance (<1 MHz) of TTJs operating as mixers, their RF capability as doublers up to 4 GHz and detection at 94 GHz. Special attention is paid to the impedance matching and cut-off frequency of the measurement set-up. The numerical study is done by means of Monte Carlo simulations. We illustrate the intrinsic functionality of the device as frequency doubler or rectifier up to THz. The role of the width of the central branch on the highfrequency response is also explored, finding different cut-off frequencies for doubling and detection as a consequence of the diverse working principles of both mechanisms and the particular geometry of the TTJs.ROOTHz (FP7-243845
Chloride anion transporters inhibit growth of methicillin-resistant: Staphylococcus aureus (MRSA) in vitro
A series of aminopyrrolic receptors were tested as anion transporters using POPC liposome model membranes. Many were found to be effective Cl(−) transporters and to inhibit clinical strains of Staphylococcus aureus growth in vitro. The best transporters proved effective against the methicillin-resistant Staphylococcus aureus (MRSA) strains, Mu50 and HP1173. Tris-thiourea tren-based chloride transporters were also shown to inhibit the growth of S. aureus. in vitro
Advances in high power short pulse fiber laser systems and technology
We review recent advances in Yb fiber lasers and amplifiers for high power short pulse systems. We go on to describe associated recent developments in fiber components for use in such systems. Examples include microstructured optical fibers for pulse compression and supercontinuum generation, and advanced fiber grating technology for chirped-pulse amplifier systems
An evaluation of the intuitiveness of the PGA modeling language notation
The Process-Goal Alignment (PGA) modeling method is a domain-specific modeling language that aims to achieve strategic fit of the business strategy with the internal infrastructure and processes. To ensure the acceptance and correct understanding of PGA models by business-oriented end-users, an intuitively understandable notation is of paramount importance. However, the current PGA notation was not formally tested up to now. In the paper at hand, we apply an evaluation technique for testing the intuitiveness of domain-specific modeling languages to bridge that research gap. Based on an analysis of the tasks, we propose improvements to six elements of the initial PGA notation. Our research contributes a comprehensive description of the empirical modeling language evaluation, which enables the reproducibility of the evaluation procedure by the conceptual modeling community
A knowledge, attitudes, and practice survey among obstetrician-gynaecologists on intimate partner violence in Flanders, Belgium
BACKGROUND: Intimate partner violence (IPV) has consistently been found to afflict one in twenty pregnant women and is therefore considered a leading cause of physical injury, mental illness and adverse pregnancy outcome. A general antenatal screening policy has been advocated, though compliance with such guidelines tends to be low. We therefore attempted to identify potential barriers to IPV screening in a context where no guidelines have been instigated yet. METHODS: Questionnaire-based Knowledge, Attitude, and Practice survey among obstetrician-gynaecologists in Flanders, Belgium (n = 478). RESULTS: The response rate was 52.1% (249/478). Gynaecologists prove rather unfamiliar with IPV and therefore largely underestimate the extent of the problem. Merely 6.8% (17/249) of the respondents ever received or pursued any kind of education on IPV. Accordingly they do feel insufficiently skilled to deal with IPV, yet sufficiently capable of recognizing IPV among their patients. Survey participants largely refute the incentive of universal screening in favour of opportunistic screening and do not consider pregnancy as a window of opportunity for routine screening. They do consider screening for IPV as an issue of medical liability and therefore do not suffer from a lack of motivation to screen. In addition, obstetrician-gynaecologists do believe that screening for IPV may be an effective means to counteract abusive behaviours. Yet, their outcome expectancy is weighed down by their perceived lack of self-efficacy in dealing with IPV, by lack of familiarity with referral procedures and by their perceived lack of available referral services. Major external or patient-related barriers to IPV screening included a perceived lack of time and fear of offending or insulting patients. Overall, merely 8.4 % (21/245) of gynaecologists in this survey performed some kind of IPV questioning on a regular basis. Finally, physician education was found to be the strongest predictor of a positive attitude towards screening and of current screening practices. CONCLUSION: Endorsement of physician training on IPV is an important first step towards successful implementation of screening guidelines for IPV. Additional introduction of enabling and reinforcement strategies such as screening tools, patient leaflets, formal referral pathways, and physician feedback may further enhance compliance with screening recommendations and guidelines
<i>Gaia</i> Data Release 1. Summary of the astrometric, photometric, and survey properties
Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7.
Aims. A summary of Gaia DR1 is presented along with illustrations of the scientific quality of the data, followed by a discussion of the limitations due to the preliminary nature of this release.
Methods. The raw data collected by Gaia during the first 14 months of the mission have been processed by the Gaia Data Processing and Analysis Consortium (DPAC) and turned into an astrometric and photometric catalogue.
Results. Gaia DR1 consists of three components: a primary astrometric data set which contains the positions, parallaxes, and mean proper motions for about 2 million of the brightest stars in common with the HIPPARCOS and Tycho-2 catalogues – a realisation of the Tycho-Gaia Astrometric Solution (TGAS) – and a secondary astrometric data set containing the positions for an additional 1.1 billion sources. The second component is the photometric data set, consisting of mean G-band magnitudes for all sources. The G-band light curves and the characteristics of ∼3000 Cepheid and RR-Lyrae stars, observed at high cadence around the south ecliptic pole, form the third component. For the primary astrometric data set the typical uncertainty is about 0.3 mas for the positions and parallaxes, and about 1 mas yr−1 for the proper motions. A systematic component of ∼0.3 mas should be added to the parallax uncertainties. For the subset of ∼94 000 HIPPARCOS stars in the primary data set, the proper motions are much more precise at about 0.06 mas yr−1. For the secondary astrometric data set, the typical uncertainty of the positions is ∼10 mas. The median uncertainties on the mean G-band magnitudes range from the mmag level to ∼0.03 mag over the magnitude range 5 to 20.7.
Conclusions. Gaia DR1 is an important milestone ahead of the next Gaia data release, which will feature five-parameter astrometry for all sources. Extensive validation shows that Gaia DR1 represents a major advance in the mapping of the heavens and the availability of basic stellar data that underpin observational astrophysics. Nevertheless, the very preliminary nature of this first Gaia data release does lead to a number of important limitations to the data quality which should be carefully considered before drawing conclusions from the data
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