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The hypotheses of oral disease-associated perioprosthetic joint infections to understand the role of oral health for endoprostheses - a narrative review
No full textAims:
Periprosthetic infections are a severe complication, causing enormous morbidity. The role of oral diseases in the development of such infections has been discussed controversially, showing a large discrepancy between prevalence of oral foci and infections of endoprostheses (EP). This narrative review aimed in explaining and discussing two hypotheses for the occurrence of oral disease-associated EP infections.
Methods and Results:
The hypotheses include two mechanisms. (1) In case of an acute exacerbation during the early healingperiod after EP surgery (first 3 months). (2) Coincidental in the context of late EP infections (after successful initial healing), where an initial periprosthetic inflammation can be colonized secondarily by oral microorganisms. In both settings,oral foci are not primarily causative for EP infection, but represent an important reservoir for EP colonization, while the immunological conditions (locally and systemically) are crucial for the onset of an EP infection. As potential consequence, patients with risk factors should be orally rehabilitated prior to EP surgery. Usage of antibiotic prophylaxis during the first 3 months after EP implantation (initial healing period) might be considered, but has no reliable evidence. To avoid morbidity of patients, radical dental clearance is unfavorable for the respective patients.
Conclusion:
Altogether, patients with EP should receive increased attention from the dental perspective alongside with dental preventive measures, because they show a high dental and periodontal treatment need
Thermodynamic and cloud evolution in a cold-air outbreak during HALO-(AC)3: quasi-Lagrangian observations compared to the ERA5 and CARRA reanalyses
No full textArctic air masses undergo intense transformations when moving southward from closed sea ice to warmer open waters in marine cold-air outbreaks (CAOs). Due to the lack of measurements of diabatic heating and moisture uptake rates along CAO flows, studies often depend on atmospheric reanalysis output. However, the uncertainties connected to those datasets remain unclear. Here, we present height-resolved airborne observations of diabatic heating, moisture uptake, and cloud evolution measured in a quasi-Lagrangian manner. The investigated CAO was observed on 1 April 2022 during the HALO-(AC)3 campaign. Shortly after passing the sea-ice edge, maximum diabatic heating rates over 6 K h−1 and moisture uptake over 0.3 were measured near the surface. Clouds started forming and vertical mixing within the deepening boundary layer intensified. The quasi-Lagrangian observations are compared with the fifth-generation global reanalysis (ERA5) and the Copernicus Arctic Regional Reanalysis (CARRA). Compared to these observations, the mean absolute errors of ERA5 versus CARRA data are 14 % higher for air temperature over sea ice (1.14 K versus 1.00 K) and 62 % higher for specific humidity over ice-free ocean (0.112 g kg−1 versus 0.069 g kg−1). We relate these differences to issues with the representation of the marginal ice zone and corresponding surface fluxes in ERA5, as well as the cloud scheme producing excess liquid-bearing, precipitating clouds, which causes a too-dry marine boundary layer. CARRA's high spatial resolution and demonstrated higher fidelity towards observations make it a promising candidate for further studies on Arctic air mass transformations
First comprehensive assessment of industrial-era land heat uptake from multiple sources
No full textThe anthropogenically intensified greenhouse effect has caused a radiative imbalance at the top of the atmosphere during the industrial period. This, in turn, has led to an energy surplus in various components of the Earth system, with the ocean storing the largest part. The land contribution ranks second with the latest observational estimates based on borehole temperature profiles, which quantify the terrestrial energy surplus to be 6 % in the last 5 decades, whereas studies based on state-of-the-art climate models scale it down to 2 %. This underestimation stems from land surface models (LSMs) having a subsurface that is too shallow, which severely constrains the land heat uptake simulated by Earth system models (ESMs). A forced simulation of the last 2000 years with the Max Planck Institute ESM (MPI-ESM) using a deep LSM captures 4 times more heat than the standard shallow MPI-ESM simulations in the historical period, well above the estimates provided by other ESMs. However, deepening the LSM does not remarkably affect the simulated surface temperature. It is shown that the heat stored during the historical period by an ESM using a deep LSM component can be accurately estimated by considering the surface temperatures simulated by the ESM using a shallow LSM and propagating them with a standalone forward model. This result is used to derive estimates of land heat uptake using all available observational datasets, reanalysis products, and state-of-the-art ESM experiments. This approach yields values of 10.5–16.0 ZJ for 1971–2018, which are 12 %–42 % smaller than the latest borehole-based estimates (18.2 ZJ)
Visualisierung topologischer Strukturen in unsicheren Skalarfeldern: Abschlussbericht
No full textTopologische Merkmale und Strukturen ermöglichen eine kompakte und auf das Wesentliche verdichtete Beschreibung von Feldern – Repräsentationen von räumlich-zeitlichen Veränderlichen – welche in Naturwissenschaft und Technik häufig auftreten. Möchte man beispielsweise Simulationsdaten aus Klimasimulationen auswerten, so interessieren meistens Regionen hoher oder niedriger Werte, sowie deren Beziehung und relative Lage. Während bereits Methoden zur topologischen Analyse deterministischer Felder existieren, wurden im Rahmen des geförderten Projekts neue Methoden im Bereich der topologischen Analyse unsicherer Skalarfelder entwickelt. Diese finden Anwendung bei der Untersuchung von Ensemble-Klimasimulationen, welche sich dadurch auszeichnen, dass mehrere Simulationsläufe mit leicht verschiedenen Startbedingungen durchgeführt wurden, und nun hinsichtlich Gemeinsamkeiten, Unterschieden, beziehungsweise Wahrscheinlichkeiten des Eintretens bestimmter Ereignisse untersucht werden. Es wurden Methoden entwickelt, die unter anderem dazu dienen, die Vielfalt in der zeitlichen Entwicklung verschiedener Ensemble-Mitglieder direkt darzustellen, mit Anwendung für die Untersuchung der Änderungen des weltweiten Niederschlags in verschiedenen Klimaänderungsszenarien. Weiterhin wurden Methoden entwickelt, um kritische Punkte in unsicheren Skalarfeldern zu extrahieren und über Ensemble-Mitglieder hinweg zu identifizieren, um die Wahrscheinlichkeit des Auftretens, die Lage und Ausprägung von Merkmalen zu charakterisieren. Dies wurde angewandt, um in Klimasimulationen des Nordatlantiks eine mögliche klimawandelbedinge Verschiebung des sogenannten Island-Tiefs und des Azoren-Hochs zu untersuchen. Die Lage und Ausprägung dieser beiden Druckgebiete sind maßgeblich für die sogenannte Nordatlantik-Oszillation, welche im Winter warme feuchte Luft nach Europa bringt und dort für milde Winter sorgt. Durch die im Projekt entwickelten Methoden, lässt sich eine robuste Verschiebung des Island-Tiefs aufzeigen, deren Stärke mit der Stärke des Klimawandels einhergeht.Topological features and structure enable a compact and distilled description of fields – representations of spatio-temporally varying quantities – which occur frequently in science and technology. For example, when analyzing data from climate simulations, one is often interested in regions of high or low values, their relation and relative position. While there exist methods for the topological analysis of deterministic fields, within this project new methods in the area of topological analysis of uncertain scalar fieldswere developed. These are applicable to the study of ensemble data from climate simulations, which are characterized by multiple simulation runs with slightly different initial conditions, and are now examined with respect to commonalities, differences, and the probability of the occurrence of certain events. Within the project methods were developed that serve, among other things, to directly show the variation in the evolution of ensemble members, with application to study the change in world-wide precipitation in different climate change scenarios. Furthermore, methods were developed to extract critical points in uncertain scalar fields and to identify them across ensemble members in order to determine the probability of occurrence, the position, and the strength of features. This was applied to climate simulations of the Northern Atlantic to study a possible shift of the so-called Icelandic Low and Azores High. The position and strength of these two pressure systems the the main drivers of the so-called Northern Atlantic Oscillation, which transports war humid air to Europe in winter time and thus causes mild winters there. With the methods developed in the project we obtained a robust finding that the Icelandic Low shifts and that the strength of this shift coincides with the strength of climate change
Polymorphs of 17O‑Implanted ST1 Spin Centers in Diamond and Spectroscopy of Strongly Coupled 13C Nuclear Spins
No full textThe so-called ST1 center in diamond is one of the very few known systems today that possesses properties similar to the nitrogen-vacancy (NV) center. The ST1 enables spin coherent control at room temperature with even larger readout contrast than NV centers and is therefore promising for quantum information or sensing at 300 K. However, the nature and methods of on-demand creation of the ST1 were still unknown and a large dispersion of the optical, spin properties, and photostability was reported. Here, using two independent methods, we definitely evidence that the ST1 center is made of oxygen. Contrarily to previous studies where the ST1 centers were found scarcely (likely created unintentionally by oxygen-plasma treatments), the centers are created here reproducibly by oxygen implantation in several samples and enable a comprehensive study of their “bulk” optical and spin properties. Electron spin resonance line widths as low as 330 kHz were measured, indicating electron spin coherence time T2* in the μs range at 300 K. Further, we report on the hyperfine interaction with 17O and with nearby 13C nuclear spins. Twenty different coupling types with 13C larger than 2.5 MHz are found. This highlights the low symmetry of the ST1, the presence of at least one carbon vacancy in the ST1 structure, and the possibility to address a larger number of discernible 13C nuclear spins than with the NV center. These results open the way to the creation and use of quantum registers or nuclear spin memories with a long coherence time based on ST1 centers, which also have potential for quantum sensing
Optical and magneto‐optical properties of pulsed laser‐deposited thulium iron garnet thin films
No full textThis work presents a combined optical and magneto‐optical spectroscopic study of
thulium iron garnet (Tm3Fe 5O12, TmIG) films on substituted gadolinium gallium
garnet (Gd2.6Ca 0.4Ga 4.1 Mg0.25 Zr0.65O12 , sGGG) substrates. Spectroscopic ellipso-
metry, transmission spectroscopy, magneto‐optical Kerr effect spectroscopy and
Raman spectroscopy results are presented for TmIG films with a thickness in the
range from 20 to 300 nm grown on sGGG by pulsed laser deposition. The complex
dielectric functions of TmIG and sGGG are determined and compared with
previously published results for bulk yttrium iron garnet and GGG, respectively.
The magneto‐optical spectroscopy corroborated with Raman spectroscopy sheds
light on strain‐induced changes as a function of TmIG film thickness
Occupational anaphylaxis—Data from the anaphylaxis registry
No full textBackground: Epidemiologic data on occupational anaphylaxis is scarce, and there is a
need of more knowledge about work-related anaphylactic episodes.
Methods: Based on the data of the Anaphylaxis Registry, we identified cases related
to occupational exposure and analyzed the elicitors, demographics, severity of clinical
reaction and management.
Results: Since 2017, 5851 cases with an information about the occupational rela-
tion of the anaphylactic episode were registered whereby 225 (3.8%) were assigned
to be caused by an occupational allergen. The vast majority of these occupational
anaphylaxis cases were caused by insects (n = 186, 82.7%) followed by food (n = 27,
12.0%) and drugs (n = 8, 3.6%). Latex elicited occupational anaphylaxis in only two
cases. Beekeepers, gardeners, farmers, and individuals working in professions as-
sociated with food handling, for example, employees in restaurants, bakery, pastry,
and cooks were most frequently affected. The comparison of the occupational in-
sect venom-induced anaphylaxis to a group of non-occupational insect anaphylaxis
in adults (n = 1842) revealed a significant younger age in occupational anaphylaxis (46
vs. 53 years), a predominance of bee-induced cases (38% vs. 17%), and a higher rate
of venom immunotherapy in a primary care setting (3.3% vs. 1.3%, p = .044). In the
occupational- versus non-occupational adults with food-induced anaphylaxis atopic
dermatitis as concomitant atopic disease was observed more frequently (n = 486; 20%
vs. 10%), although this was not significant.
Conclusion: Our data demonstrate the impact of venom allergy in work-related ana-
phylaxis. Foods and drugs are less frequently elicitors, and latex-induced occupational
anaphylaxis was rare. More data are needed to determine risk factors associated with
occupational anaphylaxis
Tropospheric sulfate from Cumbre Vieja (La Palma) observed over Cabo Verde contrasted with background conditions: A lidar case study of aerosol extinction, backscatter, depolarization and lidar ratio profiles at 355, 532 and 1064 nm
No full textIn September 2021, volcanic aerosol (mainly freshly formed sulfate plumes) originating from the eruption of Cumbre Vieja on La Palma, Canary Islands, Spain, crossed Cabo Verde at altitudes below 2 km. On 24 September 2021, an extraordinary large aerosol optical depth (AOD) close to 1 (daily mean at 500 nm) was observed at Mindelo, Cabo Verde. This event provided favorable conditions to obtain lidar-derived profiles of extinction and backscatter coefficients, lidar ratio, and depolarization ratio at 355, 532 and 1064 nm in the sulfate aerosol plume. A novel feature of the lidar system operated at Mindelo is the availability of extinction, lidar ratio and depolarization measurements at 1064 nm in addition to the standard wavelengths of 355 and 532 nm. Having measurements of these parameters at all three wavelengths is a major advantage for the aerosol characterization and in aerosol typing efforts as the lidar ratio and the particle linear depolarization ratio are key parameters for this purpose. In this article, we present the key results of the lidar observations obtained on one specific day, namely on 24 September 2021 at 04:38–05:57 UTC, including the first ever measurements of the particle extinction coefficient, the lidar ratio and the depolarization ratio at 1064 nm for volcanic sulfate, and discuss the findings in terms of aerosol optical properties and mass concentrations by comparison with a reference observation (16 September 2021) representing the typical background conditions before the start of the eruptions. We found an unusual high particle extinction coefficient of 721 ± 51, 549 ± 38 and 178 ± 13 Mm−1, as well as an enhanced lidar ratio of 66.9 ± 10.1, 60.2 ± 9.2 and 30.8 ± 8.7 sr at 355, 532 and 1064 nm, respectively, in the sulfate-dominated planetary boundary layer (PBL). The particle linear depolarization ratio was ≤ 0.9 % at all respective wavelengths. It is the first time that lidar-derived intensive aerosol optical properties could be derived for volcanic sulfate at all three wavelengths, and thus it is a highly valuable data set for global aerosol characterization. The lidar analysis also revealed a sulfate-related AOD of about 0.35 ± 0.03 at 532 nm of the total PBL-related AOD of 0.43. The rest of the AOD contribution was caused by a lofted Saharan dust layer extending from 1.4 to 5 km and leading to a total AOD of 0.79 at 532 nm. Volcanic ash contribution to the observed aerosol plumes could be mostly excluded based on trajectory analysis and the observed optical properties. Peak mass concentration was 178.5 ± 44.6 µg m−3 in the volcanic-influenced and sulfate-dominated polluted PBL, showing the hazardous potential of such sulfate plumes to significantly worsen local air quality even at remote locations
Recognizing and Looking at Masked Emotional Faces in Alexithymia
No full textAlexithymia is a clinically relevant personality construct characterized by difficulties identifying and communicating one’s emotions and externally oriented thinking. Alexithymia has been found to be related to poor emotion decoding and diminished attention to the eyes. The present eye tracking study investigated whether high levels of alexithymia are related to impairments in recognizing emotions in masked faces and reduced attentional preference for the eyes. An emotion recognition task with happy, fearful, disgusted, and neutral faces with face masks was administered to high-alexithymic and non-alexithymic individuals. Hit rates, latencies of correct responses, and fixation duration on eyes and face mask were analyzed as a function of group and sex. Alexithymia had no effects on accuracy and speed of emotion recognition. However, alexithymic men showed less attentional preference for the eyes relative to the mask than non-alexithymic men, which was due to their increased attention to face masks. No fixation duration differences were observed between alexithymic and non-alexithymic women. Our data indicate that high levels of alexithymia might not have adverse effects on the efficiency of emotion recognition from faces wearing masks. Future research on gaze behavior during facial emotion recognition in high alexithymia should consider sex as a moderating variable
Still an Unsolved Question: The Place of Cranial Magnetic Resonance Imaging in Acute Acquired Concomitant Esotropia
No full textPurpose: The aim of this study was to collect further data to estimate the risk of relevant intracranial pathology and thereby better assess the need for cranial imaging in children with acute acquired comitant esotropia (AACE). To date, there is still not enough literature on this topic to enable a consensus on the diagnostic algorithm. Methods: We analyzed data from patients with convergent strabismus who received cranial imaging via magnetic resonance imaging (MRI). Twenty-one patients received a cranial MRI for the diagnostic evaluation of AACE. The age range was from 2 to 12 years, and the mean age at the time of diagnosis was 5.5 years. Of these patients, only one exhibited insignificant MRI findings, with no therapeutic consequences. Conclusions: Our data add further evidence that AACE without neurological findings or other ophthalmologic anomalies might not be an indication for cranial MRI as a diagnostic screening tool