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Observations and modeling of areal surface albedo and surface types in the Arctic
No full textAn accurate representation of the annual evolu-
tion of surface albedo of the Arctic Ocean, especially dur-
ing the melting period, is crucial to obtain reliable climate
model predictions in the Arctic. Therefore, the output of the
surface albedo scheme of a coupled regional climate model
(HIRHAM–NAOSIM) was evaluated against airborne and
ground-based measurements. The observations were con-
ducted during five aircraft campaigns in the European Arc-
tic at different times of the year between 2017 and 2022;
one of them was part of the Multidisciplinary drifting Ob-
servatory for the Study of Arctic Climate (MOSAiC) expedi-
tion in 2020. We applied two approaches for the evaluation:
(a) relying on measured input parameters of surface type
fraction and surface skin temperature (offline) and (b) using
HIRHAM–NAOSIM simulations independently of observa-
tional data (online). From the offline method we found a sea-
sonally dependent bias between measured and modeled sur-
face albedo. In spring, the cloud effect on surface broadband
albedo was overestimated by the surface albedo parametriza-
tion (mean albedo bias of 0.06), while the surface albedo
scheme for cloudless cases reproduced the measured surface
albedo distributions for all seasons. The online evaluation re-
vealed an overestimation of the modeled surface albedo re-
sulting from an overestimation of the modeled cloud cover.
Furthermore, it was shown that the surface type parametriza-
tion contributes significantly to the bias in albedo, especially
in summer (after the drainage of melt ponds) and autumn (on-
set of refreezing). The lack of an adequate model represen-
tation of the surface scattering layer, which usually forms on
bare ice in summer, contributed to the underestimation of sur-
face albedo during that period. The difference between mod-
eled and measured net irradiances for selected flights during
the five airborne campaigns was derived to estimate the im-
pact of the model bias for the solar radiative energy budget
at the surface. We revealed a negative bias between modeled
and measured net irradiances (median: −6.4 W m−2) for op-
tically thin clouds, while the median value of only 0.1 W m−2
was determined for optically thicker cloud
Vector-Borne and Zoonotic Pathogens in Raccoon Dogs (Nyctereutes procyonoides) and Raccoons (Procyon lotor) from Schleswig-Holstein, Germany
No full textRaccoon dogs (Nyctereutes procyonoides) and raccoons (Procyon lotor) are invasive alien species originating from East Asia and North America, respectively. They are discussed as vectors and reservoirs for various infectious diseases, including vector-borne and zoonotic pathogens, and are therefore a potential threat to human and domestic animal health, as well as to biodiversity and conservation. In the years 2021 and 2022, 110 raccoon dogs (Nyctereutes procyonoides) and 30 raccoons (Procyon lotor) were screened via qPCR for the presence of Leptospira spp., Rickettsia spp. and Borreliella spp. in the German federal state of Schleswig-Holstein as part of a health and risk assessment study. Borreliella spp. were confirmed in one raccoon dog and one raccoon, identified as Borreliella afzelii in the raccoon. Leptospira spp. were found in 21 (19.44%) raccoon dogs and 2 (6.90%) raccoons. In five raccoon dogs, Leptospira spp. were identified as Leptospira borgpetersenii, Leptospira kirschneri and Leptospira interrogans
On Quantum Liouvillian Density Inequalities in the Thermal Sector
No full textIn the ground sector of a quantum field theory, the generator of the time evolution,
i.e., the Hamiltonian or energy operator, is a positive operator. However, its spatial
density, i.e., the energy density, does not share this property. Nevertheless, in many
models, it has been shown that the energy density retains some weaker form of
positivity, inherited from that of the Hamiltonian. Specifically, the expectation
value of the time-averaged energy density satisfies a state-independent lower bound,
commonly referred to as a Quantum Energy Inequality (QEI).
In the thermal sector, the situation changes significantly. The spectrum of the
generator of the time evolution, known as the Liouvillian operator, is unbounded
from below. Naively, the reason behind this behavior can be attributed to the negative
contribution to the energy coming from the reservoir that maintains the system
in thermal equilibrium. The aim of this thesis is to study the spatial density of the
Liouvillian operator and establish whether it still satisfies any (weaker) form of positivity; for instance , a positivity form inherited from the so called passivity property of the Liouvillian.
The equilibrium properties of thermal states are closely connected to Tomita-
Takesaki modular theory. Accordingly, modular theory plays a central role in our
analysis, providing both a testing ground for our results and key tools for their
derivation. Concerning this second aspect, we make use of the theory of noncommutative
Lp-spaces, within which we also establish several new useful results.
Our main result consists in the derivation of a non-trivial, state-dependent inequality
for the averaged Liouvillian density of a free massive scalar field. The
state-dependence is expressed by the presence of the non-commutative L4-norm of
the state in the corresponding lower bound. Similarly, we derive a state-dependent
lower bound for the density of the boost generator in the right wedge of Minkowski
spacetime. In light of the well-known Bisognano-Wichmann theorem, this inequality
can be interpreted as a quantum modular energy inequality for a situation in which
a modular energy density can be defined
Aspergillus fumigatus binding IgA and IgG1 are increased in bronchoalveolar lavage fluid of horses with neutrophilic asthma
No full textIntroduction: Equine asthma (EA) is a common lower airway disease in horses, but whether its pathogenesis is allergic is ambiguous. Extrinsic stimuli like hay dust induce acute exacerbation of clinical signs and sustained local neutrophilic inflammation in susceptible horses. Aspergillus fumigatus is an EA stimulus, but it is unclear if it merely acts as an IgE-provoking allergen. We aimed to comprehensively analyze immunoglobulin (Ig) isotypes in EA, elucidating their binding to different A. fumigatus antigens, and their quantities systemically in serum and locally in bronchoalveolar lavage fluid (BALF).
Methods: Serum and BALF from healthy horses (HE, n = 18) and horses with mild-moderate asthma (MEA, n = 20) or severe asthma (SEA, n = 24) were compared. Ig isotype (IgG1, IgG3/5, IgG4/7, IgG6, IgA, and IgE) binding to nine antigens (A. fumigatus lysate, and recombinant Asp f 1, Asp f 7, Asp f 8, dipeptidyl-peptidase 5, class II aldolase/adducin domain protein, glucoamylase, beta-hexosaminidase, and peptide hydrolase) was compared by enzyme-linked immunosorbent assays. Total Ig isotype contents were determined by bead-based assays.
Results: MEA and SEA differed from HE but hardly from each other. Compared to HE, asthmatic horses showed increased anti-A. fumigatus binding of IgG (BALF and serum) and IgA (BALF). Serum and BALF IgE binding and total IgE contents were similar between HE and EA. Single antigens, as well as A. fumigatus lysate, yielded similar Ig binding patterns. Serum and BALF IgG1 binding to all antigens was increased in SEA and to several antigens in MEA. Serum IgG4/7 binding to two antigens was increased in SEA. BALF IgA binding to all antigens was increased in SEA and MEA. Total BALF IgG1 and IgG4/7 contents were increased in SEA, and serum IgG4/7 content was increased in MEA compared to HE. Yet, total isotype contents differentiated EA and HE less clearly than antigen-binding Ig.
Discussion: A. fumigatus immunogenicity was confirmed without identification of single dominant antigens here. A. fumigatus provoked elevated BALF IgG1 and IgA binding, and these isotypes appear relevant for neutrophilic EA, which does not support allergy. BALF Ig isotype differentiation beyond IgE is crucial for a comprehensive analysis of immune responses to fungi in EA pathogenesis
A diachronic perspective on ‘prosodies’ in Central Chadic languages (Afroasiatic)
No full textThe paper reports on generalisations drawn from the author’s historical analysis of a sample of some five thousand words, which reflect more than two hundred lexical items from up to sixty-six Central Chadic languages and language varieties. The paper provides illustrative examples from present-day languages with explicit diachronic analyses of the evolution of their synchronic segmental and ‘prosodic’ suprasegmental structures. Four typologically characteristic prosodies (i.e., palatalisation, labialisation, nasalisation, glottalisation) operate across words, which are – in synchronic perspective – mostly monomorphemic, while in diachronic perspective they are mostly polymorphemic. The paper shows that, and how the four reconstructed prosodies lead to the diachronic emergence of innovative phonemes in the modern languages, which were not part of the segmental phonological inventories of the common proto-language. This empirical fact poses considerable challenges to the application of the well-established ‘comparative method’ as originally developed by the Neogrammarian school of historical linguistics
Proceedings of the 29th Congress of the European Society of Veterinary & Comparative Nutrition (ESVCN)
No full textComparative Analysis of Lymphocyte Populations in Post-COVID-19 Condition and COVID-19 Convalescent Individuals
No full textReduced lymphocyte counts in peripheral blood are one of the most common observations in acute phases of viral infections. Although many studies have already examined the impact of immune (dys)regulation during SARS-CoV-2 infection, there are still uncertainties about the long-term consequences for lymphocyte homeostasis. Furthermore, as persistent cellular aberrations have been described following other viral infections, patients with “Post-COVID-19 Condition” (PCC) may present similarly. In order to investigate cellular changes in the adaptive immune system, we performed a retrospective analysis of flow cytometric data from lymphocyte subpopulations in 106 patients with confirmed SARS-CoV-2 infection who received medical care at our institution. The patients were divided into three groups according to the follow-up date; laboratory analyses of COVID-19 patients were compared with 28 unexposed healthy controls. Regarding B lymphocyte subsets, levels of IgA + CD27+, IgG + CD27+, IgM + CD27− and switched B cells were significantly reduced at the last follow-up compared to unexposed healthy controls (UHC). Of the 106 COVID-19 patients, 56 were clinically classified as featuring PCC. Significant differences between PCC and COVID-19 convalescents compared to UHC were observed in T helper cells and class-switched B cells. However, we did not detect specific or long-lasting immune cellular changes in PCC compared to the non-post-COVID-19 condition
Development of an automated platform for monitoring microfluidic reactors through multi- reactor integration and online (chip-)LC/MS- detection
No full textThis work presents a novel microfluidic screening setup with real-time analytics for investigating reactions with immobilised biocatalysts. The setup combines microreactor technology, multi-reactor integration, and online (chip-)LC/MS analysis in a sequential automated workflow. We utilized in-house manufactured fused-silica glass chips as reusable packed-bed microreactors interconnected as individual tube reactors. The potential of this setup was showcased by conducting and optimising a biocatalytic aromatic bromination reaction as the first proof of concept using immobilised vanadium-dependent haloperoxidase from Curvularia inaequalis (CiVHPO). The fusion of a HaloTag™ to CiVHPO was used for efficient and mild covalent linkage of the enzyme onto chloroalkane-functionalized particles. Then, the biotransformation was continuously monitored with automated LC/MS data acquisition in a data-rich manner. By further developing the automation principle, it was possible to sequentially screen multiple different connected packed-bed microreactors for reaction optimization while using only miniature amounts of reactants and biocatalyst. Finally, we present a fast and modular chipHPLC solution for online analysis to reduce the overall solvent consumption by over 80%. We established a modern microfluidic platform for real-time reaction monitoring and evaluation of biocatalytic reactions through automation of the reactant feed integration, flexible microreactor selection, and online LC/MS analysis
An Atomistic Picture of Buildup and Degradation Reactions in Area-Selective Atomic Layer Deposition with a Small Molecule Inhibitor
No full textWe investigate the blocking layer formation of the trimethoxypropylsilane small molecule inhibitor (SMI), its blocking mechanisms, and all relevant blocking layer disintegration reactions on SiO2 in the area-selective atomic layer deposition of Al2O3 with density functional theory-based methods. The choice of amorphous silica (a-SiO2) surface models proves to be essential for obtaining the correct SMI chemistry. We demonstrate that complete blocking of reactive sites is possible here and deduce an upper SMI density limit of the resulting blocking layer that is limited by Pauli repulsion. The SMI adsorption process can nevertheless leave unreacted silanol groups, which could be remedied by using a second monodentate SMI. The SMI layer is inert against neither common aluminum precursors nor the co-reactant water as our comprehensive analysis of the various blocking layer disintegration reactions for different SMI layer densities shows. We report a new blocking mechanism of the SMI layer and propose to differentiate what is discussed as the “steric blocking” effect into the known “adsorption prevention” effect and the newly found “reactivity reduction” effect. For trimethylaluminum (TMA), an additional favorable SMI layer decomposition mechanism is found compared to that of the bulkier triethylaluminum (TEA), which could explain the lower selectivity of TMA found experimentally. Our computational work offers some principles and ideas for future experiments to improve selectivity in area-selective atomic layer deposition processes