110 research outputs found
Three-dimensional radiative transfer effects on airborne and ground-based trace gas remote sensing
Air mass factors (AMFs) are used in passive trace gas remote sensing for converting slant column densities (SCDs) to vertical column densities (VCDs). AMFs are traditionally computed with 1D radiative transfer models assuming horizontally homogeneous conditions. However, when observations are made with high spatial resolution in a heterogeneous atmosphere or above a heterogeneous surface, 3D effects may not be negligible. To study the importance of 3D effects on AMFs for different types of trace gas remote sensing, we implemented 1D-layer and 3D-box AMFs into the Monte carlo code for the phYSically correct Tracing of photons In Cloudy atmospheres (MYSTIC), a solver of the libRadtran radiative transfer model (RTM). The 3D-box AMF implementation is fully consistent with 1D-layer AMFs under horizontally homogeneous conditions and agrees very well ( < 5 % relative error) with 1D-layer AMFs computed by other RTMs for a wide range of scenarios. The 3D-box AMFs make it possible to visualize the 3D spatial distribution of the sensitivity of a trace gas observation, which we demonstrate with two examples. First, we computed 3D-box AMFs for ground-based multi-axis spectrometer (MAX-DOAS) observations for different viewing geometry and aerosol scenarios. The results illustrate how the sensitivity reduces with distance from the instrument and that a non-negligible part of the signal originates from outside the line of sight. Such information is invaluable for interpreting MAX-DOAS observations in heterogeneous environments such as urban areas. Second, 3D-box AMFs were used to generate synthetic nitrogen dioxide (NO2) SCDs for an air-borne imaging spectrometer observing the NO2 plume emitted from a tall stack. The plume was imaged under different solar zenith angles and solar azimuth angles. To demonstrate the limitations of classical 1D-layer AMFs, VCDs were then computed assuming horizontal homogeneity. As a result, the imaged NO2 plume was shifted in space, which led to a strong underestimation of the total VCDs in the plume maximum and an underestimation of the integrated line densities that can be used for estimating emissions from NO2 images. The two examples demonstrate the importance of 3D effects for several types of ground-based and airborne remote sensing when the atmosphere cannot be assumed to be horizontally homogeneous, which is typically the case in the vicinity of emission sources or in cities
Swiss results from a global observational study of venous thromboembolism risk and prophylaxis use in the acute care hospital setting: analysis from the ENDORSE study
BACKGROUND: The aim of the present analysis from the epidemiologic international day for the evaluation of patients at risk for venous thromboembolism (VTE) in the acute hospital care setting (ENDORSE) study was to evaluate the prevalence of VTE risk in acute care hospitals and the proportion of at-risk medical and surgical patients who receive recommended prophylaxis in Switzerland.
METHODS: All patients (age \u3eor=40 years) admitted to a medical ward or those (age \u3eor=18 years) admitted to a surgical ward in ten randomly selected Swiss hospitals were assessed for risk of VTE. The 2004 American College of Chest Physicians (ACCP) evidence-based consensus guidelines were used to assess VTE risk and to determine whether patients were receiving recommended thromboprophylaxis.
RESULTS: 2000 patients were eligible; of these 1153 (58%) were in surgical wards, and 847 (42%) in medical wards. According to the ACCP criteria, the proportion of surgical patients at VTE risk was similar in Switzerland (68%, between hospital range 48-86%) in comparison to the global ENDORSE study (64%) (p = 0.296). The rate of at-risk medical patients was lower in Switzerland (21%, range 3-44%) than in the global study (42%) (p \u3c0.001). The proportion of at-risk surgical patients with ACCP-recommended VTE prophylaxis was higher in Switzerland (81%, between-hospital range 76-93%) than in the global study (59%) (p \u3c0.001). Among medical patients at risk, the use of recommended thromboprophylaxis was higher in Switzerland (61%, between-hospital range 0-84%) than in the global ENDORSE (40%) (p \u3c0.001). However 56% of the patients with cancer, 41% with major trauma, and 29% undergoing vascular surgery did not receive any recommended prophylaxis. Among surgical patients at risk, the use of ACCP-recommended prophylaxis was lower in academic (77%) vs. non-academic (86%) institutions (p = 0.0025).
CONCLUSIONS: In Switzerland, although the rate of recommended thromboprophylaxis is higher than in many countries, it is still improvable in medical patients at risk according to the ACCP guidelines. Consequently, hospital wide strategies for systematic risk factor assessment and implementation of practical tools to ensure appropriate use of prophylaxis in patients at VTE risk are required
High-throughput analysis of subtelomeric chromosome rearrangements by use of array-based comparative genomic hypridization
Telomeric chromosome rearrangements may cause mental retardation, congenital anomalies, and miscarriages. Automated detection of subtle deletions or duplications involving telomeres is essential for high-throughput diagnosis, but impossible when conventional cytogenetic methods are used. Array-based comparative genomic hybridization (CGH) allows high-resolution screening of copy number abnormalities by hybridizing differentially labeled test and reference genomes to arrays of robotically spotted clones. To assess the applicability of this technique in the diagnosis of (sub)telomeric imbalances, we here describe a blinded study, in which DNA from 20 patients with known cytogenetic abnormalities involving one or more telomeres was hybridized to an array containing a validated set of human-chromosome–specific (sub)telomere probes. Single-copy-number gains and losses were accurately detected on these arrays, and an excellent concordance between the original cytogenetic diagnosis and the array-based CGH diagnosis was obtained by use of a single hybridization. In addition to the previously identified cytogenetic changes, array-based CGH revealed additional telomere rearrangements in 3 of the 20 patients studied. The robustness and simplicity of this array-based telomere copy-number screening make it highly suited for introduction into the clinic as a rapid and sensitive automated diagnostic procedure
Mapping the spatial distribution of NO2 with in situ and remote sensing instruments during the Munich NO2 imaging campaign
We present results from the Munich Nitrogen dioxide (NO2) Imaging Campaign (MuNIC), where NO2 near-surface concentrations (NSCs) and vertical column densities (VCDs) were measured with stationary, mobile, and airborne in situ and remote sensing instruments in Munich, Germany. The most intensive day of the campaign was 7 July 2016, when the NO2 VCD field was mapped with the Airborne Prism Experiment (APEX) imaging spectrometer.
The spatial distribution of APEX VCDs was rather smooth, with a horizontal gradient between lower values upwind and higher values downwind of the city center. The NO2 map had no pronounced source signatures except for the plumes of two combined heat and power (CHP) plants. The APEX VCDs have a fair correlation with mobile multi-axis differential optical absorption spectroscopy (MAX-DOAS) observations from two vehicles conducted on the same afternoon (r=0.55).
In contrast to the VCDs, mobile NSC measurements revealed high spatial and temporal variability along the roads, with the highest values in congested areas and tunnels. The NOx emissions of the two CHP plants were estimated from the APEX observations using a mass-balance approach. The NOx emission estimates are consistent with CO2 emissions determined from two ground-based Fourier transform infrared (FTIR) instruments operated near one CHP plant. The estimates are higher than the reported emissions but are probably overestimated because the uncertainties are large, as conditions were unstable and convective with low and highly variable wind speeds. Under such conditions, the application of mass-balance approaches is problematic because they assume steady-state conditions. We conclude that airborne imaging spectrometers are well suited for mapping the spatial distribution of NO2 VCDs over large areas. The emission plumes of point sources can be detected in the APEX observations, but accurate flow fields are essential for estimating emissions with sufficient accuracy. The application of airborne imaging spectrometers for studying NSCs is less straightforward and requires us to account for the non-trivial relationship between VCDs and NSCs
Childhood socioeconomic position and objectively measured physical capability levels in adulthood: a systematic review and meta-analysis
<p><b>Background:</b> Grip strength, walking speed, chair rising and standing balance time are objective measures of physical capability that characterise current health and predict survival in older populations. Socioeconomic position (SEP) in childhood may influence the peak level of physical capability achieved in early adulthood, thereby affecting levels in later adulthood. We have undertaken a systematic review with meta-analyses to test the hypothesis that adverse childhood SEP is associated with lower levels of objectively measured physical capability in adulthood.</p>
<p><b>Methods and Findings:</b> Relevant studies published by May 2010 were identified through literature searches using EMBASE and MEDLINE. Unpublished results were obtained from study investigators. Results were provided by all study investigators in a standard format and pooled using random-effects meta-analyses. 19 studies were included in the review. Total sample sizes in meta-analyses ranged from N = 17,215 for chair rise time to N = 1,061,855 for grip strength. Although heterogeneity was detected, there was consistent evidence in age adjusted models that lower childhood SEP was associated with modest reductions in physical capability levels in adulthood: comparing the lowest with the highest childhood SEP there was a reduction in grip strength of 0.13 standard deviations (95% CI: 0.06, 0.21), a reduction in mean walking speed of 0.07 m/s (0.05, 0.10), an increase in mean chair rise time of 6% (4%, 8%) and an odds ratio of an inability to balance for 5s of 1.26 (1.02, 1.55). Adjustment for the potential mediating factors, adult SEP and body size attenuated associations greatly. However, despite this attenuation, for walking speed and chair rise time, there was still evidence of moderate associations.</p>
<p><b>Conclusions:</b> Policies targeting socioeconomic inequalities in childhood may have additional benefits in promoting the maintenance of independence in later life.</p>
Enhancing protective microglial activities with a dual function TREM2 antibody to the stalk region
Triggering receptor expressed on myeloid cells 2 (TREM2) is essential for the transition of homeostatic microglia to a disease‐associated microglial state. To enhance TREM2 activity, we sought to selectively increase the full‐length protein on the cell surface via reducing its proteolytic shedding by A Disintegrin And Metalloproteinase (i.e., α‐secretase) 10/17. We screened a panel of monoclonal antibodies against TREM2, with the aim to selectively compete for α‐secretase‐mediated shedding. Monoclonal antibody 4D9, which has a stalk region epitope close to the cleavage site, demonstrated dual mechanisms of action by stabilizing TREM2 on the cell surface and reducing its shedding, and concomitantly activating phospho‐SYK signaling. 4D9 stimulated survival of macrophages and increased microglial uptake of myelin debris and amyloid β‐peptide in vitro. In vivo target engagement was demonstrated in cerebrospinal fluid, where nearly all oluble TREM2 was 4D9‐bound. Moreover, in a mouse model for Alzheimer's disease‐related pathology, 4D9 reduced amyloidogenesis, enhanced microglial TREM2 expression, and reduced a homeostatic marker, suggesting a protective function by driving microglia toward a disease‐associated state
Austrian Research and Technology Report 2023
Der Forschungs- und Technologiebericht ist der Lagebericht über die aus Bundesmitteln geförderte Forschung, Technologie und Innovation in Österreich und wird im Auftrag des Bundesministeriums für Bildung, Wissenschaft und Forschung (BMBWF) in Einvernehmen mit dem Bundesministerium für Klimaschutz, Umwelt, Energie, Mobilität, Innovation und Technologie (BMK) sowie dem Bundesministerium für Arbeit und Wirtschaft (BMAW) erstellt.
Der vorliegende Bericht steht im Zeichen eines komplexen Wandels auf unterschiedlichen Ebenen, einerseits getrieben durch multiple Krisen, die nicht nur das Innovationsverhalten von Unternehmen und wissenschaftlichen Akteurinnen und Akteuren verändern, sondern auch veränderte Rahmenbedingungen mit sich bringen. Die Twin Transition ist allgegenwärtig. Im vorliegenden Bericht wird mit dem Schwerpunktthema der Fokus auf die Grüne Transformation in Forschung und Wirtschaft gelegt.
Abstrac
Österreichischer Forschungs- und Technologiebericht 2023
Der Forschungs- und Technologiebericht ist der Lagebericht über die aus Bundesmitteln geförderte Forschung, Technologie und Innovation in Österreich und wird im Auftrag des Bundesministeriums für Bildung, Wissenschaft und Forschung (BMBWF) in Einvernehmen mit dem Bundesministerium für Klimaschutz, Umwelt, Energie, Mobilität, Innovation und Technologie (BMK) sowie dem Bundesministerium für Arbeit und Wirtschaft (BMAW) erstellt.
Der vorliegende Bericht steht im Zeichen eines komplexen Wandels auf unterschiedlichen Ebenen, einerseits getrieben durch multiple Krisen, die nicht nur das Innovationsverhalten von Unternehmen und wissenschaftlichen Akteurinnen und Akteuren verändern, sondern auch veränderte Rahmenbedingungen mit sich bringen. Die Twin Transition ist allgegenwärtig. Im vorliegenden Bericht wird mit dem Schwerpunktthema der Fokus auf die Grüne Transformation in Forschung und Wirtschaft gelegt
Austrian Research and Technology Report 2022
Der Forschungs-und Technologiebericht 2022 gibt einen Überblick über die aus Bundesmitteln geförderte Forschung, Technologie und Innovation (FTI) in Österreich. Neben der Darstellung aktueller forschungspolitischer Entwicklungen, die den Stand der Umsetzung der mit Ende 2020 verabschiedeten FTI-Strategie 2030, forschungsrelevante Teilstrategien und neueste Entwicklungen im Hochschulbereich behandelt, werden auf Grundlage rezenter Daten aus diversen internationalen Rankings, aus der F&E (Forschung & Entwicklung)-Erhebung 2019 und der Globalschätzung 2022 Analysen zur nationalen und internationalen FTI-Performance Österreichs erstellt
Cellulose and lignin biosynthesis is altered by ozone in wood of hybrid poplar (Populus tremula×alba)
Wood formation in trees is a dynamic process that is strongly affected by environmental factors. However, the impact of ozone on wood is poorly documented. The objective of this study was to assess the effects of ozone on wood formation by focusing on the two major wood components, cellulose and lignin, and analysing any anatomical modifications. Young hybrid poplars (Populus tremula×alba) were cultivated under different ozone concentrations (50, 100, 200, and 300 nl l−1). As upright poplars usually develop tension wood in a non-set pattern, the trees were bent in order to induce tension wood formation on the upper side of the stem and normal or opposite wood on the lower side. Biosynthesis of cellulose and lignin (enzymes and RNA levels), together with cambial growth, decreased in response to ozone exposure. The cellulose to lignin ratio was reduced, suggesting that cellulose biosynthesis was more affected than that of lignin. Tension wood was generally more altered than opposite wood, especially at the anatomical level. Tension wood may be more susceptible to reduced carbon allocation to the stems under ozone exposure. These results suggested a coordinated regulation of cellulose and lignin deposition to sustain mechanical strength under ozone. The modifications of the cellulose to lignin ratio and wood anatomy could allow the tree to maintain radial growth while minimizing carbon cost
- …