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A double observer approach for tracking the abundance of Alpine marmot
No full textReliable methods for tracking changes in population abundance are crucial for effective wildlife management. We monitored a population of Alpine marmots (Marmota marmota) in Stelvio National Park (Italian Alps) over an 8-year period, from 2017 to 2024. Absolute abundance estimates were obtained by analyzing 180 individual capture histories using robust-design CMR models. Each year, six Independent Double Observer (IDO) sessions were conducted shortly after capture to obtain session-specific abundance estimates using Chapman’s estimator, which were averaged in each year using Cochran’s method. In addition, the IDO raw data were used to derive the average and maximum number of marmots counted by both observers within each year. We then evaluated the performance of IDO and simple combinations of independent counts against benchmark CMR estimates. The average IDO obtained using Cochran’s method underestimated population size by 55% (95% CI: 53–58%) compared to CMR estimates, likely reflecting availability bias, as the marmot’s burrowing behavior limits their exposure to detection during sampling. Despite this, IDO and CMR were strongly and positively correlated (r = 0.88; rho = 0.90), and their relationship, modeled through a log–log regression, explained about 80% of the variance. In contrast, simple counts correlated only moderately (averaged counts: r = 0.74; rho = 0.88) or weakly (maximum counts: r = 0.39; rho = 0.33) with CMR estimates. Their corresponding log–log models explained substantially less variation (51% and 8% respectively). Our findings suggest that IDO is a reliable method for tracking numerical variation in marmot populations, although it revealed a modest tendency toward saturation, with increasing underestimation of relative abundance at higher densities. IDO outperformed non-probabilistic methods in detecting population trends, likely due to its ability to adjust for detection probability – though some assumptions may not have been fully met. Replicating this study in other species within the Marmotini tribe is needed to assess IDO’s performance across different ecological contexts
Economic and health consequence frames affect COVID-19 vaccine incentive attitudes in Germany– a survey based framing experiment
No full textBackgroundSARS-CoV-2 vaccines have significantly reduced human and economic losses. Nevertheless, vaccine hesitancy remains a major issue in many countries, including Germany. Recent studies have shown that public health framing and incentives can boost immunization rates. However, available evidence is fragmented and inconclusive regarding the effectiveness of different framing messages, types of incentives, and the size of financial incentives across different populations.MethodsThis randomized, controlled survey experiment elicited the attitudes of 6,685 Germans towards 4 financial/non-financial SARS-CoV-2 immunization incentives (food voucher, football tickets, participation in lottery, immediate monetary compensation), and tested whether framing (individual/collective, health/economic consequences) affected said attitudes. We assigned participants to five study arms (control: no frame; experiment: 1 of 4 frames) and measured attitudes towards immunization incentives, and the amount of monetary compensation deemed appropriate, should such an incentive be considered.ResultsWhile > 75% of our sample considered all 4 incentives to be not meaningful, all frames increased favorable views towards the financial incentives lottery/money and the average amount deemed acceptable for immediate monetary compensation. Interaction models showed that all frames have similar effects across core subgroups, e.g. age-cohorts, gender, vaccine doses.ConclusionsAcross a sample of 6,685 Germans, we show that 4 different frames detailing the potential individual/collective consequences of COVID-19 have very similar effects on attitudes towards monetary incentives for SARS-CoV-2 immunization. Our results suggest that the existence of frames rather than specific narratives is key to increasing favorable views towards immunization incentives.Clinical trial numberNot applicable
Optimization of the size and location of the FOVs for CBCT capture of impacted lower third molars
No full textBackgroundCone beam computed tomography (CBCT) is an established diagnostic tool for impacted wisdom teeth (third molars (3 M)) in proximity of the mandibular nerve canal. This study aims to define the minimum field-of-view (FOV) size and its localization to reduce radiation exposure. As reference, the chin rest of the CBCT device was used.MethodsThree-dimensional CBCT data sets were used to analyze the bilateral positions and dimensions of the wisdom teeth. A total of 215 wisdom teeth from a study population with a mean age of 21 years, including data from 82 male and 58 female patients, were mapped. By transformation into a common coordinate space using the device’s chin rest as a joint denominator, the optimal size and location for uni- and bilateral capture of the wisdom teeth were determined, for both best-case and worst-case scenarios with regard to patient positioning.ResultsThe minimal FOVs for the lower 3 M capture were H 23.5 mm × R 35.4 mm in the best-case scenario assuming optimal patient positioning and H 35.4 mm × R 36.6 mm in the worst-case scenario with rotational deviation along the transversal axis. For the upper 3 M, the minimal FOVs were H 29.9 mm × R 29.2 mm in the best-case scenario and H 38.6 mm × R 35.6 mm in the worst-case scenario. Unilateral capture of both the upper and lower 3 M required FOV dimensions of H 51.7 mm × R 39.8 mm and H 44.8 mm × R 36.8 mm, respectively. For bilateral capture of all four 3 M, the best-case FOV was H 44.8 mm × R 84.8 mm and the worst-case FOV was H 51.7 mm × R 85.6 mm.DiscussionThis research provides indication-specific FOVs for uni- and bilateral imaging of the upper and lower 3 M. Taking into account optimal clinical practices for CBCT imaging, this study aims to propose clinically feasible FOV dimensions while meeting the technical specifications of commonly used CBCT devices. Clinical application of the results may help reduce radiation exposure of patients receiving CBCT imaging of the wisdom teeth. Transfer of the present results to other CBCT devices requires further research.Trial registrationThe study is registered in the German Trial Register with the number DRKS00026149, 2024/02/21
Visualization and semi-quantitative analysis of dissolution processes at artificial structures in carbonate rocks using optical, 3D micro-scanning and confocal laser scanning microscopy
No full textThe Northern Alpine Foreland Basin in southeast Germany hosts more deep geothermal plants than any other region in the country. Its primary aquifer, the Upper Jurassic, is composed of permeable carbonates containing water with temperatures exceeding C in the southern margin and low total dissolved solids ( 2 g/L) at depths of up to 4000 m. Its sustainable use of geothermal energy depends on an efficient exploitation strategy concerning the entire reservoir, which is influenced by the development of flow paths between production and reinjection wells. The Upper Jurassic’s waters show a carbonate signature with calcium and magnesium often replaced by sodium due to ion exchange along the infiltration pathways. These waters become undersaturated upon cooling, and dissolution around reinjection wells has been previously documented. Assessing short- to medium-term localized dissolution experimentally is challenging. While dissolution kinetics and overall volume changes have been studied in the field, microscopic changes to flow paths remain less under investigation. This study used a time-lapse experiment to evaluate microscopic changes during dissolution in limestone samples exposed to elevated CO2 partial pressure in an autoclave. For an effective observation, we used artificial structures to localize the dissolution effects. Post-treatment analysis included Raman microscopy, 3D micro-scanning, confocal laser scanning microscopy (CLSM), and optical microscopy with image stacking, with a strong focus on the latter three. Each imaging method had distinct strengths and limitations. CLSM provided high-resolution surface roughness assessments but could not capture areas beneath overhangs. Optical microscopy is affordable and user-friendly and was effective for visualizing preferential dissolution pathways but lacked precise roughness information. 3D micro-scanning, despite lower resolution, uniquely resolved overhangs. The dissolution processes led to significant surface roughening, forming micrometer-scale moldic pores and preferential pathways. Artificial structures widened and deformed, with 3D micro-scanning quantifying these changes effectively and CLSM revealing fine-scale roughness details. Increased fracture surface roughness and widening of flow paths enhance water transport and dissolution, potentially accelerating thermal breakthroughs at geothermal plants. Understanding these processes is essential for predicting reservoir behavior, improving geothermal energy extraction efficiency, and exploiting aquifers sustainably
Traumatic hip dislocations in children and adolescents: diagnostic challenges and the significance of MRI imaging - a multi-center study
No full textBackgroundTraumatic hip dislocations in children and adolescents are rare but can lead to severe outcomes like avascular necrosis. Delayed reductions, often due to overlooked dislocations in initial imaging, pose a major risk. The variability in symptoms and emergency care challenges early diagnosis. This multi-center study evaluates diagnostic approaches to enhance protocols for identifying traumatic hip dislocations in childhood.MethodsThis retrospective multi-center study included 76 patients (aged ≤ 17 years) with acute traumatic hip dislocations and open growth plates from 16 German hospitals. Patient data and imaging from 1979 to 2022 were analyzed, with statistical evaluation performed using SPSS under ethical guidelines.ResultsX-rays (single and biplanar views) were the primary diagnostic method, utilized in 85% of cases. Dislocations were missed in 12% (9 cases), primarily among children under eight years, with half of those under four. Delayed reductions (15.8%, n = 12) were linked to undetected dislocations in imaging in 9 cases. Conventional X-rays frequently missed dislocations, whereas MRI successfully identified all cases. Among the 76 patients, 54 (71%) had associated injuries, with 57.9% (n = 44) diagnosed exclusively via MRI.ConclusionTimely diagnosis of traumatic hip dislocations is crucial, as delays increase the risk of femoral head necrosis. An algorithmic approach is essential for young children, where dislocations may not be readily suspected. MRI is vital in the secondary diagnostic phase, providing superior visualization of associated injuries, including acetabular avulsions and soft tissue interpositions highlighting the need for integration of MRI into a unified diagnostic algorithm for children suspected of such injuries
Serotonin transporter deficiency, but not absence of platelet serotonin, impairs thrombus formation in a model of deep vein thrombosis
No full textBackgroundThe majority of peripheral serotonin is stored in dense granules of circulating blood platelets and released upon platelet activation. Recently, an immunomodulatory role of serotonin in inflammation has been found, influencing the recruitment of leukocytes, especially neutrophils.ObjectivesSince deep vein thrombosis creates an inflammatory milieu, called thromboinflammation, this study examined the impact of peripheral platelet serotonin on the development of venous thrombosis.MethodsTo induce deep vein thrombosis, a stenosis model of the inferior vena cava was used. Six- to 8-week-old C57BL/6 (wild-type [WT]), selective serotonin reuptake inhibitor-treated C57BL/6 (depleted serotonin pools in platelets), serotonin transporter knockout (SERT-/-), and tryptophan hydroxylase 1 knockout (Tph1-/-) mice were used. Thrombus volume was measured, and its composition was analyzed after 48 hours using immunofluorescence microscopy. Neutrophils and platelet-neutrophil complexes were analyzed using flow cytometry.ResultsSERT-/- mice formed significantly fewer and smaller thrombi compared with WT (mean ± SD, 1.09 mm3 ± 2.53 vs 13.1 mm3 ± 11.1; P = .002) and Tph1-/- mice (1.09 mm3 ± 2.53 vs 11.3 mm3 ± 6.84; P = .02) and had lower levels of neutrophils in the blood. Thrombi in the WT and Tph1-/- groups were comparable. In SERT-/- mice, there was no decrease in circulating platelet-neutrophil complexes.ConclusionThe extent of venous thrombosis did not depend on peripheral serotonin in our mouse model, but rather on the presence of the serotonin transporter. In the absence of the serotonin transporter, the thrombogenic property as well as the overall immune response to venous thrombosis was reduced. The distribution of the serotonin transporter on immune cells and its thrombogenic potential should be studied further
Thermodynamics of hard sphere and spherocylinder mixtures—scaled particle theory and Monte Carlo simulations
No full textWe review the literature on scaled particle theory (SPT) and its extensions and discuss results applied to describe the thermodynamics of hard particle mixtures. After explaining the basic concepts of SPT to compute the free energy of immersing a particle into a mixture, examples are discussed for the simple case of a hard sphere (HS) dispersion and the free volume fraction of ghost spheres in a HS dispersion. Next, the concept is applied to mixtures, and general expressions are shown that relate the free volume fraction in mixtures to the key thermodynamic properties, such as the chemical potential(s) and (osmotic) pressure. Subsequently, it is revealed how these concepts can be extended towards multi-component systems. It is shown that free volume fractions provide chemical potentials and total pressure of multi-component mixtures, and thereby yield the full equation of state. We present novel results for ternary particle dispersions composed of hard spherocylinders and two types of HSs differing in size. Throughout, we show the accuracy of SPT by comparing the results with those of Monte Carlo computer simulations
Chemotherapy-free neoadjuvant pembrolizumab combined with trastuzumab and pertuzumab in HER2-enriched early breast cancer (WSG-KEYRICHED-1): a single-arm, phase 2 trial
No full textMulti-angle averaging approach for measuring the coating thickness on thin transparent polymer films
No full textPolymer films with a thickness in the two-digit micrometer range are coated with nanometer-thin oxide layers in roll-to-roll coating systems. The coating improves the properties of the film, such as gas or water permeation. Maintaining a sufficiently large coating thickness is crucial to ensure its barrier function; thus, inline quality control of the thickness is indispensable. For this purpose, we have developed a sensing principle that addresses specific absorption bands of the coating via a reflection measurement in the infrared spectral range. However, for thin and weakly absorbing polymer substrates, light is reflected not only by the coating and the surface of the polymer. Partly it is also transmitted and reflected by the backside of the film, leading to interference effects that significantly affect the measurement signal. As industrial films vary in thickness by several percent and their exact values are unknown, determining the thickness of an oxide coating is hindered. In this paper, we demonstrate an approach for measuring coating thickness on such varying polymer films by averaging the interferences obtained at multiple angles of incidence. Calculations and measurements on industrial film samples indicate the effectiveness of our approach. It produces results with nm precision and nm accuracy for a thickness in the range of 5–100 nm. Furthermore, we discuss a possible implementation of this approach in an inline measurement system by fulfilling its requirements, for example, versatility and compactness
