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Evaluation of downward and upward solar irradiances simulated by the Integrated Forecasting System of ECMWF using airborne observations above Arctic low-level clouds
No full textThe simulations of upward and downward irradiances by the Integrated Forecasting System (IFS) of
the European Centre for Medium-Range Weather Forecasts are compared with broadband solar irradiance mea-
surements from the Arctic CLoud Observations Using airborne measurements during polar Day (ACLOUD)
campaign. For this purpose, offline radiative transfer simulations were performed with the ecRad radiation
scheme using the operational IFS output. The simulations of the downward solar irradiance agree within the
measurement uncertainty. However, the IFS underestimates the reflected solar irradiances above sea ice signif-
icantly by −35 W m−2. Above open ocean, the agreement is closer, with an overestimation of 28 W m−2. A
sensitivity study using measured surface and cloud properties is performed with ecRad to quantify the contribu-
tions of the surface albedo, cloud fraction, ice and liquid water path and cloud droplet number concentration to
the observed bias. It shows that the IFS sea ice albedo climatology underestimates the observed sea ice albedo,
causing more than 50 % of the bias. Considering the higher variability of in situ observations in the parame-
terization of the cloud droplet number concentration leads to a smaller bias of −27 W m−2 above sea ice and a
larger bias of 48 W m−2 above open ocean by increasing the range from 36–69 to 36–200 cm−3. Above sea ice,
realistic surface albedos, cloud droplet number concentrations and liquid water paths contribute most to the bias
improvement. Above open ocean, realistic cloud fractions and liquid water paths are most important for reducing
the model–observation differences
Global high-resolution drought indices for 1981–2022
No full textDroughts are among the most complex and devastating natural hazards globally. High-resolution
datasets of drought metrics are essential for monitoring and quantifying the severity, duration, frequency, and
spatial extent of droughts at regional and particularly local scales. However, current global drought indices are
available only at a coarser spatial resolution ( > 50 km). To fill this gap, we developed four high-resolution
(5 km) gridded drought records based on the standardized precipitation evaporation index (SPEI) covering the
period 1981–2022. These multi-scale (1–48 months) SPEI indices are computed based on monthly precipita-
tion (P ) from the Climate Hazards Group InfraRed Precipitation with Station Data (CHIRPS, version 2) and
Multi-Source Weighted-Ensemble Precipitation (MSWEP, version 2.8), and potential evapotranspiration (PET)
from the Global Land Evaporation Amsterdam Model (GLEAM, version 3.7a) and hourly Potential Evap-
otranspiration (hPET). We generated four SPEI records based on all possible combinations of P and PET
datasets: CHIRPS_GLEAM, CHIRPS_hPET, MSWEP_GLEAM, and MSWEP_hPET. These drought records
were evaluated globally and exhibited excellent agreement with observation-based estimates of SPEI, root zone
soil moisture, and vegetation health indices. The newly developed high-resolution datasets provide more de-
tailed local information and can be used to assess drought severity for particular periods and regions and
to determine global, regional, and local trends, thereby supporting the development of site-specific adapta-
tion measures. These datasets are publicly available at the Centre for Environmental Data Analysis (CEDA;
https://doi.org/10.5285/ac43da11867243a1bb414e1637802dec) (Gebrechorkos et al., 2023)
Die neuzeitlichen Handschriften der Nullgruppe (Ms 01201-01518): Beschrieben von Detlef Döring
No full textDer Band schließt die Beschreibung der neuzeitlichen Handschriften der Null-Gruppe ab. Der inhaltliche Schwerpunkt der erfassten Handschriften liegt - wie schon bei den früheren Bänden - auf dem Gebiet der Universitäts- und Wissenschaftsgeschichte vor allem des mitteldeutschen Raumes. Erheblich ist die Zahl der Vorlesungsnachschriften des 17. bis 20. Jahrhunderts, die zum größten Teil in Leipzig angefertigt wurden. Dazu tritt eine Reihe von Gelehrtennachlässen, unter denen die Korrespondenzen einiger Naturwissenschaftler, Mediziner und Philologen nationale und internationale Bedeutung besitzen. Im Bestand befinden sich auch Texte außer-universitärer Thematik, so zum Vormärz (R. Blum), zur Missionsgeschichte, zur Kunstgeschichte (K. Kollwitz, M. Klinger) oder zur Geschichte Sachsens. Tagebücher verschiedenster Provenienz, Reiseberichte, Akten gelehrter Sozietäten, Werkmanuskripte, bellestristische Texte u.a. runden das Bild ab
Illuminating the Path to Enhanced Bioimaging by Phosphole-based Fluorophores
No full textAs the research of biological systems becomes increasingly complex, there is a growing demand for fluorophores with a diverse range of wavelengths. In this study, we introduce phosphole-based fluorophores that surpass existing options like dansyl chloride. The reactive S−Cl bond in chlorosulfonylimino-5-phenylphosphole derivatives allows rapid and direct coupling to peptides making the fluorophores easily introducible to peptides. This coupling process occurs under mild conditions, demonstrated for [F7,P34]-NPY and its shorter analogues. Peptides linked with our fluorophores exhibit similar receptor activation to the control peptide, while maintaining high stability and low toxicity, making them ideal biolabeling reagents. In fluorescence microscopy experiments, they can be easily visualized even at low concentrations, without suffering from the typical issue of bleaching. These phosphole-based fluorophores represent a significant leap forward in the field. Their versatility, ease of modification, superior performance, and applicability in biological labeling make them a promising choice for researchers seeking advanced tools to unravel the details of complex biological systems
Risk of developing psoriatic arthritis in psoriasis cohorts with arthralgia: exploring the subclinical psoriatic arthritis stage
No full textObjective Subjects with subclinical psoriatic arthritis (PsA), defined as the presence of arthralgia in psoriasis (PsO), are at higher risk of PsA but scant real-world data exist. Our aims were to (1) estimate the probability of PsA development in subclinical PsA, (2) characterise subclinical PsA symptoms and (3) determine the clinical patterns at PsA diagnosis.
Methods Patients with PsO, mainly subclinical PsA, were evaluated longitudinally in two European cohorts. The key outcome was new-onset PsA. Musculoskeletal symptoms including inflammatory and non-inflammatory symptoms before PsA diagnosis were collected. Occurrence of PsA was analysed with survival analysis and cumulative incidence functions (CIFs).
Results 384 patients with PsO were included with a mean follow-up of 33.0 (±20.9) months. 311 of 384 (80.9%) had subclinical PsA with a PsA incidence rate of 7.7 per 100 patient-years. Subclinical PsA displayed a higher risk of PsA development compared with PsO (HR=11.7 (95% CI 1.57 to 86.7), p=0.016). The probability of new-onset PsA estimated by the CIF was 9.4% (95% CI 4.7% to 10.6%) at month 12 and 22.7% (95% CI 17.2% to 28.6%) at month 36. 58.9% of cases reported inflammatory symptoms in the months immediately prior to PsA diagnosis but prior non-inflammatory symptoms were evident in 83.9% prior to PsA diagnosis. Peripheral joint swelling was the predominant PsA presentation pattern (82.1%).
Conclusions The probability of PsA development among subclinical PsA was relatively high, emphasising the importance of emergent musculoskeletal symptoms when aiming for PsA prevention. Joint swelling was the dominant feature in new-onset PsA, likely reflecting clinical confidence in recognising joint swelling
Agile Work Practices: Relationships with Occupational Well-Being and Team Performance
No full textAgile work practices are central to modern organizations and have gained increasing scientific attention due to their impact on team collaboration and performance. However, the underlying mechanisms of the relation between agile work practices, occupational well-being, and team performance remain largely unexplored. This cumulative dissertation addresses this research gap within four empirical studies, contributing to theorizing on work design and team dynamics. Building on the job demands-resources theory, the first study investigates the direct and indirect relationships between agile work practices, job demands and resources, and occupational well-being by analyzing data from a two-wave online survey of employees in agile teams. The second study builds on the results of Study 1 by using qualitative interviews to identify the opportunities and risks of different agile work practices for occupational well-being. Additionally, potential moderating effects of individual and organizational resources are explored. Studies 3a and 3b examine the direct and indirect relationships between daily stand-up meetings, job satisfaction, and team performance, drawing on psychological safety theory and using an online survey (Study 3a) and an experimental study (Study 3b). Overall, this dissertation provides important theoretical and practical contributions for designing agile work practices in order to unlock their full potential for employee well-being and team performance, while mitigating potential risks
Der Einfluss von Wnt1 auf kraniofazialen Knochen und Zahnwurzelentwicklung
No full textCraniofacial bone and tooth development is a complicated biological process that begins during embryonic development and persists into postnatal stages. During this process, different cell types are involved, which signal through distinct pathways to organize the development of the skull. One of these signaling pathways is the Wnt pathway which plays a fundamental role in neural crest cell migration and differentiation. Here ongoing research aims to elucidate the precise impacts of individual components within the Wnt signaling pathway on the development of craniofacial bone and teeth subsequent to neural crest migration. In earlier projects, the impact of the Wnt1 ligand on mandible bone as well as embryonic teeth development was investigated, where a tet-off mouse model was employed and Wnt1 is selectively expressed under the regulation of the 2.3kb Col1α1
promoter, primarily influencing osteoblasts, odontoblasts, and cementoblasts.
In this project using the same mouse model I continued to study the effect of Wnt1 on early and late craniofacial bone development in addition to early postnatal dental development. Regarding prenatal craniofacial bone development, we first induced the expression of Wnt1 in these cells after neural crest migration had preceded at E10.5 and investigated the effect at P0. To study the effect of Wnt1 on postnatal development we induced Wnt1 at birth P0 and investigated the effects at P14 and P28 days mice. Using micro-computed tomography, histological staining and bulk RNAseq we revealed a significant increase in bone mass in all three stages. Nonetheless, the magnitude of the increase in bone mass varied significantly depending on the cells' origin. Bone derived from neural crest cells was markedly more affected compared to bone originating from mesoderm-derived cells. Furthermore, the induction of Wnt1 during embryonic development resulted in an osteopetrosis-like phenotype which is characterized by massive bone mass and a notable absence of osteoclasts. Interestingly, when Wnt1 was induced postnatally, the impact on bone was initially milder, leading to only a slight increase in bone mass in P14 Wnt1 mice with no observed tooth malformation. However, in P28 Wnt1 mice, the pups were significantly affected, displaying noticeable growth retardation and shortened tooth roots, thinner roots dentin, overgrowth of cementum, and ectopic pulp. Intriguingly, in contrast to the P0 Wnt1 pups, osteoclasts were not inhibited in these mice either.
These findings illuminate the intricate interplay between the timing of Wnt1 induction, cellular origins, and the resulting phenotypic outcomes in craniofacial development. They not only advance our understanding of the role of Wnt signaling in bone and tooth development but also underscore the complexities that underlie these processes, paving the way for further exploration and potential therapeutic interventions in craniofacial disorders
Perceptual Sensitivity to Tonal Alignment in Nuer
No full textThis paper examines the perceptual threshold in patterns of tonal timing (alignment) of Falling versus Low tones. The results indicate a remarkable sensitivity among the listeners. In a perception experiment with 30 participants, we tested how native speakers of the West Nilotic language Nuer responded to stimuli in which the timing of the F0 fall that distinguishes Low versus Fall following a High target is manipulated. We measured the threshold for the responses to shift tone perception from 25% to 75%. The results show that listeners only needed an average of 19 ms to differentiate between the melodic shapes and as little as 13 ms for one item. Perceptual sensitivity this fine-grained is not expected based on what is known about the Just Noticeable Difference (JND) from previous studies. Results from non-tonal languages report a sensitivity threshold for tonal timing of at least 50 ms at category boundaries. This difference suggests that whether or not subjects speak a tone language may be a determining factor in their JND
The effects of causal and self-efficacy beliefs on help-seeking for people with depressive complaints: a quasi-experimental online study
No full textOnly approximately a third of people with depressive symptoms
seek professional health care. Furthermore, people labelled as mentally ill may
experience stigmatisation, which can impede help-seeking behaviour
Tethered balloon-borne observations of thermal-infrared irradiance and cooling rate profiles in the Arctic atmospheric boundary layer
No full textClouds play an important role in controlling the radiative energy budget of the Arctic atmospheric boundary layer. To quantify the impact of clouds on the radiative heating or cooling of the lower atmosphere and of the surface, vertical profile observations of thermal-infrared irradiances were collected using a radiation measurement system carried by a tethered balloon. We present 70 profiles of thermal-infrared radiative quantities measured in summer 2020 during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition and in autumn 2021 and spring 2022 in Ny-Ålesund, Svalbard. Measurements are classified into four groups: cloudless, low-level liquid-bearing cloud, elevated liquid-bearing cloud, and elevated ice cloud. Cloudless cases display an average radiative cooling rate of about −2 K d−1 throughout the atmospheric boundary layer. Instead, low-level liquid-bearing clouds are characterized by a radiative cooling up to −80 K d−1 within a shallow layer at cloud top, while no temperature tendencies are identified underneath the cloud layer. Radiative transfer simulations are performed to quantify the sensitivity of radiative cooling rates to cloud microphysical properties. In particular, cloud top cooling is strongly driven by the liquid water path, especially in optically thin clouds, while for optically thick clouds the cloud droplet number concentration has an increased influence. Additional radiative transfer simulations are used to demonstrate the enhanced radiative importance of the liquid relative to ice clouds. To analyze the temporal evolution of thermal-infrared radiation profiles during the transitions from a cloudy to a cloudless atmosphere, a respective case study is investigated