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Every moment, countless meteoroids enter our atmosphere unseen. The detection and measurement of meteors offer the unique opportunity to gain insights into the composition of our solar systems' celestial bodies. Researchers, therefore, carry out a wide-area-sky-monitoring to secure 360-degree video material, saving every single entry of a meteor. Existing machine intelligence cannot accurately recognize events of meteors intersecting the earth's atmosphere due to a lack of high-quality training data publicly available. This work presents four reusable open source solutions for researchers trained on data we collected due to the lack of available labeled high-quality training data. We refer to the proposed dataset as the NightSkyUCP dataset, consisting of a balanced set of 10,000 meteor- and 10,000 non-meteor-events. Our solutions apply various machine learning techniques, namely classification, feature learning, anomaly detection, and extrapolation. For the classification task, a mean accuracy of 99.1\% is achieved. The code and data are made public at figshare with DOI: 10.6084/m9.figshare.16451625, 11 Pages, 10 Figures, Accepted for publication in MNRAS Journal

PMT is a protein toxin produced by Pasteurella multocida serotypes A and D. As causative agent of atrophic rhinitis in swine, it leads to rapid degradation of the nasal turbinate bone. The toxin acts as a deamidase to modify a crucial glutamine in heterotrimeric G proteins, which results in constitutive activation of the G proteins and permanent stimulation of numerous downstream signaling pathways.Using a lentiviral based genome wide CRISPR knockout screen in combination with a lethal toxin chimera, consisting of full length inactive PMT and the catalytic domain of diphtheria toxin, we identified the LRP1 gene encoding the Low-Density Lipoprotein Receptor-related protein 1 as a critical host factor for PMT function. Loss of LRP1 reduced PMT binding and abolished the cellular response and deamidation of heterotrimeric G proteins, confirming LRP1 to be crucial for PMT uptake. Expression of LRP1 or cluster 4 of LRP1, respectively, restored intoxication of the knockout cells. In summary our data demonstrate secretory cells as entry site of PMT into airway epithelia and present LRP1 as crucial host entry factor for PMT intoxication by acting as its primary cell surface receptor.

Naturally occurring polyphenols can modify the molecular properties of food allergens. For the major apple allergen Mal d 1 it has been postulated that chemical reactions with polyphenols cause permanent changes in the tertiary structure, causing a loss of conformational IgE epitopes and reducing allergenicity. In our study, we investigated the effect that reactions with oxidized polyphenols have on the structure of Mal d 1 by mass spectrometry and NMR spectroscopy. We showed that a surface-exposed cysteine residue in this allergen spontaneously reacts with oxidized polyphenols under formation of a defined covalent adduct. Chemical modification of Mal d 1 did not destabilize or perturb the three-dimensional fold, nor did it interfere with ligand binding to its internal pocket. A structural model of the chemically modified apple allergen is presented, which reveals that the bound polyphenol partially covers a conformational IgE epitope on the protein surface.

Rabies infects all mammals; however, transmission cycles are only maintained in certain bat and carnivore species. The high incidence of rabies in Greater Kudu (Tragelaphus strepsiceros) observed in Namibia for over 40 years has led to postulation that independent virus transmission is occurring within this antelope population. We have analysed extensive experimental, epidemiological, phylogeographic and deep sequence data, which collectively refute maintenance of an independent rabies cycle in kudu. As rabies in kudu continues to have a negative impact on the Namibian agricultural sector, measures to protect kudu have been investigated, including the use of a third-generation oral rabies vaccine. Initial results show protection of kudu from rabies infection via the oral route, with an appropriate bait design, different application schedules and vaccination doses further enhancing the immune response. Rabies in kudu is a complex interplay at the wildlife-livestock interface and requires a concerted approach to successfully control.

In this study, we investigated the clinical impact of different urinary tract infection (UTI) phenotypes occurring within the first year after renal transplantation. The population included 2368 transplantations having 2363 UTI events. Patients were categorized into four groups based on their compiled UTI events observed within the first year after transplantation: (i) no colonization or UTI (n = 1404; 59%), (ii) colonization only (n = 353; 15%), (iii) occasional UTI with 1-2 episodes (n = 456; 19%), and (iv) recurrent UTI with ≥3 episodes (n = 155; 7%). One-year mortality and graft loss rate were not different among the four groups, but patients with recurrent UTI had a 7-10 ml/min lower eGFR at year one (44 ml/min vs. 54, 53, and 51 ml/min; p .001). UTI phenotypes had no impact on long-term patient survival (p = .33). However, patients with recurrent UTI demonstrated a 10% lower long-term death-censored allograft survival (p .001). Furthermore, recurrent UTI was a strong and independent risk factor for reduced death-censored allograft survival in a multivariable analysis (HR 4.41, 95% CI 2.53-7.68, p .001). We conclude that colonization and occasional UTI have no impact on pertinent outcomes, but recurrent UTI are associated with lower one-year eGFR and lower long-term death-censored allograft survival. Better strategies to prevent and treat recurrent UTI are needed.

Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. 3-(1H,1H,2H,2H-Perfluorooctyl)-1-vinylimidazolium chloride [2126844–17–3], a strong fluorosurfactant with remarkably high solubility in water, was expediently converted into the respective doubly NHC-complexed silver salt with nitrate as counter ion in quantitative yield. Due to its vinyl substituents, [bis(3-(1H,1H,2H,2H-perfluorooctyl)-1-vinylimidazol-2-ylidene)silver(I)] nitrate, Ag(FNHC)2NO3, represents a polymerizable N-heterocyclic carbene transfer reagent, thus potentially offering simple and robust access to coordination polymers with crosslinking metal bridges. The compound was characterized by infrared and NMR spectroscopy, mass spectrometry as well as elemental analysis, and supplemented by X-ray single-crystal structure determination. It crystallizes in the monoclinic crystal system in the space group P21/c. With 173.3◦, the geometry of the Ag-carbene bridge deviates slightly from linearity. The disordered perfluoroalkyl side chains exhibit a helical conformation.

The synthesis of 1-silolyl and 1-germolyl triflates from the corresponding chlorides by salt metathesis reaction is reported. These covalent triflates are ideal starting materials for the preparation of ionic silolyl- and germolyl-imidazolium triflates by their reaction with N-heterocyclic carbenes. Similarily, ionic silolyl- and germolyl-oxophosphonium triflates are obtained by substitution of the triflate group by triethylphosphane oxide Et

SummaryCentrosomes are membraneless organelles that nucleate microtubules. At their core is a pair of centrioles that recruit pericentriolar material (PCM), a phase-separated condensate. In many cell types, including human cells, centrosomes are surrounded by endoplasmic reticulum-derived membranes of unknown structure and function. Using volume electron microscopy, we show that the C. elegans centrosome is surrounded by a membrane reticulum that we call the centriculum, for centrosome-associated membrane reticulum. Increasing centriculum size by genetic means led to expansion of the PCM and increased microtubule nucleation capacity, an unexpected finding given that the PCM is a membraneless condensate. We provide evidence that the centriculum serves as a microtubule “filter” by limiting the number of microtubules that can elongate fully. We also show the centriculum fuses with the nuclear envelope during mitosis. We propose that this fusion contributes to nuclear envelope breakdown by transducing forces from the elongating spindle to the nuclear membranes.

Neural approximations of scalar and vector fields, such as signed distance functions and radiance fields, have emerged as accurate, high-quality representations. State-of-the-art results are obtained by conditioning a neural approximation with a lookup from trainable feature grids that take on part of the learning task and allow for smaller, more efficient neural networks. Unfortunately, these feature grids usually come at the cost of significantly increased memory consumption compared to stand-alone neural network models. We present a dictionary method for compressing such feature grids, reducing their memory consumption by up to 100x and permitting a multiresolution representation which can be useful for out-of-core streaming. We formulate the dictionary optimization as a vector-quantized auto-decoder problem which lets us learn end-to-end discrete neural representations in a space where no direct supervision is available and with dynamic topology and structure. Our source code will be available at https://github.com/nv-tlabs/vqad., SIGGRAPH 2022. Project Page: https://nv-tlabs.github.io/vqad/

Airborne observations of vertical aerosol particle distributions are crucial for detailed process studies and model improvements. Tethered balloon systems represent a less expensive alternative to aircraft to capture shallow atmospheric boundary layers (ABL). This study presents the newly developed cubic aerosol measurement platform (CAMP) for balloon-borne observations of aerosol particle microphysical properties. With an edge length of 30 cm and a weight of 9 kg, the cube is an environmentally robust instrument platform intended for measurements at low temperatures, with a particular focus on applications in cloudy Arctic ABLs. The aerosol instrumentation onboard CAMP comprises two condensation particle counters with different lower detection limits, one optical particle size spectrometer, and a miniaturized absorption photometer. Comprehensive calibrations and characterizations of the instruments were performed in laboratory experiments. The first field study with a tethered balloon system took place at the TROPOS research station in Melpitz, Germany, in the winter of 2019. At ambient temperatures between -10 and 15 °C, the platform was operated up to 1.5 km height on 14 flights under a clear sky and cloudy conditions. The continuous aerosol observations at the ground station served as a reference for evaluating the CAMP measurements. During two subsequent balloon flights on the late morning of 15 February, descending layers with increased concentrations of nucleation mode particles were observed above a shallow well-mixed surface layer separated by a weakening temperature inversion. A subsequent increase in nucleation mode particles on the ground after the balloon flights suggests a downward mixing of the particles. Based on the laboratory instrument characterizations and the observations during the field campaign, CAMP demonstrated the capability to provide comprehensive aerosol particle measurements in cold and cloudy ABL.

Cosmological simulations are crucial tools in studying the Universe, but they typically do not directly match real observed structures. Constrained cosmological simulations, on the other hand, are designed to match the observed distribution of galaxies. Here we present constrained simulations based on spectroscopic surveys at a redshift of z~2.3, corresponding to an epoch of nearly 11 Gyrs ago. This allows us to 'fast-forward' the simulation to our present-day and study the evolution of observed cosmic structures self-consistently. We confirm that several previously-reported protoclusters will evolve into massive galaxy clusters by our present epoch, including the 'Hyperion' structure that we predict will collapse into a giant filamentary supercluster spanning 100 Megaparsecs. We also discover previously unknown protoclusters, with lower final masses than typically detectable by other methods, that nearly double the number of known protoclusters within this volume. Constrained simulations, applied to future high-redshift datasets, represents a unique opportunity for studying early structure formation and matching galaxy properties between high and low redshifts., Submitted: 10 November 2021; Accepted: 28 April 2022 in Nature Astronomy https://www.nature.com/articles/s41550-022-01693-0 32 pages, 9 Figures

Rezension zu Langnickel, R. (2021): Prolegomena zur Pädagogik des gespaltenen Subjekts. Ein notwendiger RISS in der Sonderpädagogik. Opladen, Berlin, Toronto: Barbara Budrich