630 research outputs found
Pathogenic Yersinia and Listeria monocytogenes in organic pork production
The goal of this study is to determine the prevalence of pathogenic Yersinia and Listeria monocytogenes in organic pork production and assess risks in different steps of the pork production chain
Radiographic outcome of root canal treatment in general dental practice: tooth type and quality of root filling as prognostic factors
Objective:This study evaluated the radiographic outcome of root canal treatments (RCTs) performed by general dental practitioners (GDPs) with focus on tooth type and quality of root filling. Materials and methods:The target population included all patients receiving root filling by GDPs in City of Helsinki in 2010-2011. Equal numbers of each tooth type (anteriors, premolars, molars) by jaw were included, resulting in 426 teeth. Pre- and post-operative periapical radiographs were assessed to evaluate periapical status and quality of root filling. Statistical evaluation utilized Chi-squared tests, Cohen's kappa and logistic regression modelling. Results:The overall success rate of RCT was 67.4%, being 76.8%, 69.7% and 55.6% (p <.001) for anteriors, premolars and molars, respectively. The quality of root fillings varied by tooth type (p <.001); optimal fillings were least frequent (43%) in molars. In multifactorial analysis, RCTs were more likely to succeed in non-molars (OR = 1.8), in teeth with optimal root fillings (OR = 3.6) and in teeth without apical periodontitis (OR = 3.2). Conclusion:The quality of root fillings and radiographic outcome of RCTs varied considerably according to tooth type; success was least likely in molars. Improvement is needed in quality of RCTs by GDPs.Peer reviewe
The effect of illumination on the time to, and pupil area of, maximum mydriasis
This study was designed to evaluate the mydriatic effects of patients being dilated under differing illumination conditions. Twenty subjects, 1 a females and 1 a males, had their pupils dilated under darkened conditions and under normal illumination to determine if there would be a difference in the rate of mydriasis or overall pupil size at the point of maximum dilation. Iris colour and gender were separately evaluated factors in dilation results. Subjects were dilated using one drop each of 1% tetracaine, 2.5% phenylephrine HCI and 1% tropicamide. Pupil diameter was periodically measured using a Cogan pupillometer starting 6 minutes after drop instillation. Measurements with the pupillometer were taken at two-minute intervals throughout the 3 a-minute test period. The final measurement 33 minutes after instillation of the dilating drops was taken with a biomicroscope reticule; both horizontal and vertical diameters were measured. No Significant differences were seen between gender, iris colour and illumination type on the rate of maximum mydriasis. However, the relative pupil area was significantly greater following dilation under normal illumination conditions
Segregation, precipitation, and \alpha-\alpha' phase separation in Fe-Cr alloys: a multi-scale modelling approach
Segregation, precipitation, and phase separation in Fe-Cr systems is
investigated. Monte Carlo simulations using semiempirical interatomic
potential, first-principles total energy calculations, and experimental
spectroscopy are used. In order to obtain a general picture of the relation of
the atomic interactions and properties of Fe-Cr alloys in bulk, surface, and
interface regions several complementary methods has to be used. Using Exact
Muffin-Tin Orbitals method the effective chemical potential as a function of Cr
content (0-15 at.% Cr) is calculated for a surface, second atomic layer and
bulk. At ~10 at.% Cr in the alloy the reversal of the driving force of a Cr
atom to occupy either bulk or surface sites is obtained. The Cr containing
surfaces are expected when the Cr content exceeds ~10 at.%. The second atomic
layer forms about 0.3 eV barrier for the migration of Cr atoms between bulk and
surface atomic layer. To get information on Fe-Cr in larger scales we use
semiempirical methods. Using combined Monte Carlo molecular dynamics
simulations, based on semiempirical potential, the precipitation of Cr into
isolated pockets in bulk Fe-Cr and the upper limit of the solubility of Cr into
Fe layers in Fe/Cr layer system is studied. The theoretical predictions are
tested using spectroscopic measurements. Hard X-ray photoelectron spectroscopy
and Auger electron spectroscopy investigations were carried out to explore Cr
segregation and precipitation in Fe/Cr double layer and Fe_0.95Cr_0.05 and
Fe_0.85Cr_0.15 alloys. Initial oxidation of Fe-Cr was investigated
experimentally at 10^-8 Torr pressure of the spectrometers showing intense
Cr_2O_3 signal. Cr segregation and the formation of Cr rich precipitates were
traced by analysing the experimental spectral intensities with respect to
annealing time, Cr content, and kinetic energy of the exited electron.Comment: 16 pages, 14 figures, 52 reference
ESABALT - Improvement of Situational Awareness in the Baltic with the Use of Crowdsourcing
This paper presents the key assumptions and preliminary research on an integrated system called ESABALT, for enhancing maritime safety, which incorporates the latest technological advances in positioning, e-Navigation, Earth observation systems and multi-channel cooperative communications. The most novel part of the ESABALT concept, however, is a focus on user-driven crowdsourcing techniques for information gathering and integration. The system will consist of a situational awareness solution for real-time maritime traffic monitoring via utilizing various positioning technologies; an observation system of the marine environment relevant to transportation and accidents including assessing the sea ice, oil spread, waves, wind etc.; and a methodology for context-aware maritime communication with cooperative, multi-channel capabilities. The paper presents the intelligent, novel, user-driven solution and associated services developed in ESABALT for enhancing the maritime safety in the whole Baltic area
Reliability of prehospital patient classification in helicopter emergency medical service missions
Background Several scores and codes are used in prehospital clinical quality registries but little is known of their reliability. The aim of this study is to evaluate the inter-rater reliability of the American Society of Anesthesiologists physical status (ASA-PS) classification system, HEMS benefit score (HBS), International Classification of Primary Care, second edition (ICPC-2) and Eastern Cooperative Oncology Group (ECOG) performance status in a helicopter emergency medical service (HEMS) clinical quality registry (CQR). Methods All physicians and paramedics working in HEMS in Finland and responsible for patient registration were asked to participate in this study. The participants entered data of six written fictional missions in the national CQR. The inter-rater reliability of the ASA-PS, HBS, ICPC-2 and ECOG were evaluated using an overall agreement and free-marginal multi-rater kappa (Kappa(free)). Results All 59 Finnish HEMS physicians and paramedics were invited to participate in this study, of which 43 responded and 16 did not answer. One participant was excluded due to unfinished data entering. ASA-PS had an overall agreement of 40.2% and Kappa(free) of 0.28 in this study. HBS had an overall agreement of 44.7% and Kappa(free) of 0.39. ICPC-2 coding had an overall agreement of 51.5% and Kappa(free) of 0.47. ECOG had an overall agreement of 49.6% and Kappa(free) of 0.40. Conclusion This study suggests a marked inter-rater unreliability in prehospital patient scoring and coding even in a relatively uniform group of practitioners working in a highly focused environment. This indicates that the scores and codes should be specifically designed or adapted for prehospital use, and the users should be provided with clear and thorough instructions on how to use them.Peer reviewe
FLIM reveals alternative EV-mediated cellular up-take pathways of paclitaxel
In response to physiological and artificial stimuli, cells generate nano-scale extracellular vesicles (EVs) by encapsulating biomolecules in plasma membrane-derived phospholipid envelopes. These vesicles are released to bodily fluids, hence acting as powerful endogenous mediators in intercellular signaling. EVs provide a compelling alternative for biomarker discovery and targeted drug delivery, but their kinetics and dynamics while interacting with living cells are poorly understood. Here we introduce a novel method, fluorescence lifetime imaging microscopy (FLIM) to investigate these interaction attributes. By FLIM, we show distinct cellular uptake mechanisms of different EV subtypes, exosomes and microvesicles, loaded with anti-cancer agent, paclitaxel. We demonstrate differences in intracellular behavior and drug release profiles of paclitaxel-containing EVs. Exosomes seem to deliver the drug mostly by endocytosis while microvesicles enter the cells by both endocytosis and fusion with cell membrane. This research offers a new real-time method to investigate EV kinetics with living cells, and it is a potential advancement to complement the existing techniques. The findings of this study improve the current knowledge in exploiting EVs as next-generation targeted drug delivery systems.Peer reviewe
High resolution Compton scattering as a Probe of the Fermi surface in the Iron-based superconductor
We have carried out first principles all-electron calculations of the
(001)-projected 2D electron momentum density and the directional Compton
profiles along the [100], [001] and [110] directions in the Fe-based
superconductor LaOFeAs within the framework of the local density approximation.
We identify Fermi surface features in the 2D electron momentum density and the
directional Compton profiles, and discuss issues related to the observation of
these features via Compton scattering experiments.Comment: 4 pages, 3 figure
Genetic drift precluded adaptation of an insect seed predator to a novel host plant in a long-term selection experiment
Host specialization is considered a primary driver of the enormous diversity of herbivorous insects. Trade-offs in host use are hypothesized to promote this specialization, but they have mostly been studied in generalist herbivores. We conducted a multi-generation selection experiment to examine the adaptation of the specialist seed-feeding bug, Lygaeus equestris, to three novel host plants (Helianthus annuus, Verbascum thapsus and Centaurea phrygia) and to test whether trade-offs promote specialization. During the selection experiment, body size of L. equestris increased more on the novel host plant H. annuus compared to the primary host plant, Vincetoxicum hirundinaria, but this effect was not observed in other fitness related traits. In addition to selection, genetic drift caused variation among the experimental herbivore populations in their ability to exploit the host plants. Microsatellite data indicated that the level of within-population genetic variation decreased and population differentiation increased more in the selection line feeding on H. annuus compared to V. hirundinaria. We found a negative correlation between genetic differentiation and heterozygosity at the end of the experiment, suggesting that differentiation was significantly affected by genetic drift. We did not find fitness trade-offs between L. equestris feeding on the four hosts. Thus, trade-offs do not seem to promote specialization in L. equestris. Our results suggest that this insect herbivore is not likely to adapt to a novel host species in a time-scale of 20 generations despite sufficient genetic variation and that genetic drift disrupted the response to selection
Differences in code terminology and frequency of findings in meat inspection of finishing pigs in seven European countries
The overall objectives of meat inspection are to contribute to food safety, animal welfare, and animal health. In the European Union (EU), there is a request for a modernised meat inspection system that addresses these objectives in a more valid, feasible and cost-effective way than does the traditional system. One part of the modernisation deals with the coding system to register meat inspection findings. Although unified standards are set at the EU level for judgement criteria regarding fitness of meat for consumption, different national systems are in force. The question is the extent of the differences and whether there is a basis for harmonisation. To investigate this, information was gathered about the code systems in Denmark, Finland, Germany, Italy, Norway, Portugal and Spain. Moreover, meat inspection data covering pigs slaughtered in 2019 were collected. A comparison of the number of codes available, the terminology and the frequencies of the findings registered was undertaken. Codes with a similar meaning were grouped. Hereby, two lists were compiled showing the most common codes leading to total and to partial condemnation. Substantial variations in the percentage of condemned pigs and in the terms used were identified, and possible reasons behind this are discussed. Moreover, a strengths-weaknesses-opportunities-threats (SWOT)-like analysis was applied to the coding systems. Finally, the reasons for unfitness of meat given in the EU Food Inspection Regulation 2019/627 were compared to the national code lists. The results show the systems in force varied substantially, and each system had its advantages and disadvantages. The diverse terminology observed made it a challenge to compare data between countries. Development of harmonised terminology for meat inspection findings is suggested, enabling comparison of data between abattoirs, regions, and countries, while respecting the national epidemiological situation, the local food safety culture, and the trade agreements in force
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