Results of WICOVIR Gargle Pool PCR Testing in German Schools Based on the First 100,000 Tests

Background: Opening schools and keeping children safe from SARS-CoV-2 infections at the same time is urgently needed to protect children from direct and indirect consequences of the COVID-19 pandemic. To achieve this goal, a safe, efficient, and cost-effective SARS-CoV-2 testing system for schools in addition to standard hygiene measures is necessary. Methods: We implemented the screening WICOVIR concept for schools in the southeast of Germany, which is based on gargling at home, pooling of samples in schools, and assessment of SARS-CoV-2 by pool rRT-PCR, performed decentralized in numerous participating laboratories. Depooling was performed if pools were positive, and results were transmitted with software specifically developed for the project within a day. Here, we report the results after the first 13 weeks in the project. Findings: We developed and implemented the proof-of-concept test system within a pilot phase of 7 weeks based on almost 17,000 participants. After 6 weeks in the main phase of the project, we performed >100,000 tests in total, analyzed in 7,896 pools, identifying 19 cases in >100 participating schools. On average, positive children showed an individual CT value of 31 when identified in the pools. Up to 30 samples were pooled (mean 13) in general, based on school classes and attached school staff. All three participating laboratories detected positive samples reliably with their previously established rRT-PCR standard protocols. When self-administered antigen tests were performed concomitantly in positive cases, only one of these eight tests was positive, and when antigen tests performed after positive pool rRT-PCR results were already known were included, 3 out of 11 truly positive tests were also identified by antigen testing. After 3 weeks of repetitive WICOVIR testing twice weekly, the detection rate of positive children in that cohort decreased significantly from 0.042 to 0.012 (p = 0.008). Interpretation: Repeated gargle pool rRT-PCR testing can be implemented quickly in schools. It is an effective, valid, and well-received test system for schools, superior to antigen tests in sensitivity, acceptance, and costs

Magnetic resonance imaging of neuroinflammation in a mouse model of multiple sclerosis

Die kraniale und spinale Bildgebung mittels Magnetresonanztomographie (MRT) hat in den vergangenen Jahren einen zentralen Stellenwert zur Diagnosestellung, Verlaufs- und Therapiekontrolle der Multiplen Sklerose (MS) erlangt. Jedoch besteht trotz hoher Sensitivität der kontrastmittelgestützten MRT bei der Darstellung von entzündlichen Läsionen des zentralen Nervensystems (ZNS) noch immer eine Diskrepanz zwischen den klinischen Symptomen des Patienten und den Befunden der Bildgebung, bekannt als „klinisch- radiologisches Paradox“ der MS. Zielsetzung dieser Studie war eine differenziertere Visualisierung einzelner Teilaspekte der Pathophysiologie der MS mittels MRT. Dazu wurden in einem Tiermodell für MS, der experimentellen autoimmunen Enzephalomyelitis, zwei experimentelle MRT Kontrastmittel, die paramagnetischen Nanopartikel VSOP und das Gadoliniumderivat Gadofluorin M (Gf), im Vergleich zu dem herkömmlichen Kontrastmittel Gadopentetat-Dimeglumin (Gd-DTPA) untersucht. SJL/J Mäuse wurden nach Transfer von Proteolipid- spezifischen, enzephalitogenen T-Zellen, bzw. Ovalbumin-spezifischen, ZNS- irrelevanten T-Zellen in einer Subgruppe, zu verschiedenen Zeitpunkten während des Krankheitsverlaufs mit einem 7 Tesla Kleintier MRT vor und nach Kontrastmittelgabe untersucht. Die MRT Schnittsequenzen wurden mit konventionell histologischen und immunhistochemisch gefärbten Gewebeschnitten korreliert. Beide experimentelle Kontrastmittel stellten zusätzliche Läsionen dar, die mit Gd-DTPA nicht detektiert werden konnten. Die Verteilung der Läsionen umfasste das gesamte ZNS und ähnelte dem Läsionsmuster beschrieben bei MS. Gf zeigte sich besonders geeignet für die Visualisierung entzündlicher Hirnnervenveränderungen, z.B. des Nervus opticus. Zudem wurde eine ausgeprägte Kontrastmittelanreicherung im Plexus choroideus und anderen zirkumventrikulären Organen von erkrankten Mäusen festgestellt. VSOP erwies sich ausgesprochen sensitiv in der Darstellung von Bluthirnschrankenveränderungen und fungierte gleichzeitig als zellulärer Marker für aktivierte Makrophagen/Mikroglia. Durch Anwendung von VSOP und Gf konnten verschiedene zelluläre, parenchymatöse und vaskuläre Veränderungen während einer entzündlichen Erkrankung des zentralen Nervensystems in vivo mittels MRT beobachtet werden, die der konventionellen Bildgebung bislang verborgen blieben.Magnetic resonance imaging (MRI) of the brain and the spinal cord has gained a central role for the diagnosis and paraclinical assessment of disease progression in patients suffering from multiple sclerosis (MS). However, despite high sensitivity of contrast-enhanced MRI for the visualization of inflammatory lesions within in the central nervous system (CNS), there is still a mismatch between the clinical symptoms of the patient and the burden of disease seen on MRI described as the “clinico-radiological paradox” of MS. The aim of the study was to investigate novel MRI techniques to address certain aspects of the pathophysiology of MS. Two novel MRI contrast agents, paramagnetic nanoparticles (VSOP) and gadolinium based Gadofluorine M (Gf), were investigated in experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, and compared to the conventional contrast agent gadopentate- dimeglumine (Gd-DTPA). Hereby, SJL/J mice were imaged at different time points during the course of disease on a dedicated 7 Tesla rodent MRI, before and after transfer of proteolipid-protein specific encephalitogenic T-cells, or Ovalbumine-specific CNS-irrelevant T-cells respectively. MRI data were correlated with brain slices stained with immunofluoresence and conventional histological techniques. Both experimental contrast agents revealed additional contrast-enhancing lesions not detected on Gd-DTPA-enhanced images. The lesion distribution was similar to the pattern of lesions described in MS. In detail, Gf was particularly sensitive for the detection of inflammation of the cranial nerves, e.g. the optic nerve. Additionally, Gf largely enhanced in the choroid plexus and other circumventricular organs of EAE mice. VSOP detected blood- brain-barrier breakdown with high sensitivity, but was simultaneously incorporated into activated macrophages/microglia, highlighting these cells on T2*-weighted MRI. Applying VSOP and Gf-enhanced MRI, we could monitor different cellular, parenchymal and vascular alterations during CNS inflammation in vivo, which were occult for conventional MR imaging

Estimation of antibody levels after COVID-19 vaccinations : Preliminary evidence for immune interoception

To date, 72 % of the world’s population has received at least one COVID-19 vaccination. The number of antibodies produced by some individuals is exponentially higher than in others, for various mostly unknown reasons. This variation causes great diversity in the future susceptibility to infection by the original or variants of the SARS-CoV-2 virus. The following study investigated whether individuals were able to estimate the strength of their antibody response after their COVID-19 vaccinations. 166 recently vaccinated participants provided a blood sample for determination of antibody titers. Participants were asked to estimate how many antibodies they thought they had produced, and were further asked how protected they felt from COVID-19 due to vaccination. Both self-rated antibody levels, and feelings of protection against COVID-19 were significantly related to their actual IgG spike antibody titers, after controlling for age, days since vaccination, BMI and cross vaccination. These results suggest that individuals may have a form of “immune interoception” which relates to their response to their COVID-19 vaccination.publishe

Influenza transmission dynamics quantified from RNA in wastewater in Switzerland

INTRODUCTION: Influenza infections are challenging to monitor at the population level due to many mild and asymptomatic cases and similar symptoms to other common circulating respiratory diseases, including COVID-19. Methods for tracking cases outside of typical reporting infrastructure could improve monitoring of influenza transmission dynamics. Influenza shedding into wastewater represents a promising source of information where quantification is unbiased by testing or treatment-seeking behaviours. METHODS: We quantified influenza A and B virus loads from influent at Switzerland’s three largest wastewater treatment plants, serving about 14% of the Swiss population (1.2 million individuals). We estimated trends in infection incidence and the effective reproductive number (Re) in these catchments during a 2021/22 epidemic and compared our estimates to typical influenza surveillance data. RESULTS: Wastewater data captured the same overall trends in infection incidence as laboratory-confirmed case data at the catchment level. However, the wastewater data were more sensitive in capturing a transient peak in incidence in December 2021 than the case data. The Re estimated from the wastewater data was roughly at or below the epidemic threshold of 1 during work-from-home measures in December 2021 but increased to at or above the epidemic threshold in two of the three catchments after the relaxation of these measures. The third catchment yielded qualitatively the same results but with wider confidence intervals. The confirmed case data at the catchment level yielded comparatively less precise R_e estimates before and during the work-from-home period, with confidence intervals that included one before and during the work-from-home period. DISCUSSION: Overall, we show that influenza RNA in wastewater can help monitor nationwide influenza transmission dynamics. Based on this research, we developed an online dashboard for ongoing wastewater-based influenza surveillance in Switzerland.ISSN:1424-7860ISSN:1424-399

Combined Characterization Techniques to Understand the Stability of a Variety of Organic Photovoltaic Devices - the ISOS-3 inter- laboratory collaboration

Trabajo presentado como comunicación al "Reliability of Photovoltaic Cells, Modules, Components, and Systems V" celebrada del 13 al 16 de Agosto del 2012 en San Diego (USA).-- et al.This work is part of the inter-laboratory collaboration to study the stability of seven distinct sets of state-of-the-art organic photovoltaic (OPVs) devices prepared by leading research laboratories. All devices have been shipped to and degraded at the Danish Technical University (DTU, formerly RISO-DTU) up to 1830 hours in accordance with established ISOS-3 protocols under defined illumination conditions. In this work we present a summary of the degradation response observed for the NREL sample, an inverted OPV of the type ITO/ZnO/P3HT:PCBM/PEDOT:PSS/Ag/Al, under full sun stability test. The results reported from the combination of the different characterization techniques results in a proposed degradation mechanism. The final conclusion is that the failure of the photovoltaic response of the device is mainly due to the degradation of the electrodes and not to the active materials of the solar cell. © (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.Peer Reviewe

TOF-SIMS investigation of degradation pathways occurring in a variety of organic photovoltaic devices - the ISOS-3 inter-laboratory collaboration

International audienceThe present work is the fourth (and final) contribution to an inter-laboratory collaboration that was planned at the 3rd International Summit on Organic Photovoltaic Stability (ISOS-3). The collaboration involved six laboratories capable of producing seven distinct sets of OPV devices that were degraded under well-defined conditions in accordance with the ISOS-3 protocols. The degradation experiments lasted up to 1830 hours and involved more than 300 cells on more than 100 devices. The devices were analyzed and characterized at different points of their lifetimes by a large number of non-destructive and destructive techniques in order to identify specific degradation mechanisms responsible for the deterioration of the photovoltaic response. Work presented herein involves time-of-flight secondary ion mass spectrometry (TOF-SIMS) in order to study chemical degradation in-plane as well as in-depth in the organic solar cells. Various degradation mechanisms were investigated and correlated with cell performance. For example, photo-oxidation of the active material was quantitatively studied as a function of cell performance. The large variety of cell architectures used (some with and some without encapsulation) enabled valuable comparisons and important conclusions to be drawn on degradation behaviour. This comprehensive investigation of OPV stability has significantly advanced the understanding of degradation behaviour in OPV devices, which is an important step towards large scale application of organic solar cells

Stability and degradation of organic photovoltaics fabricated, aged, and characterized by the ISOS 3 inter-laboratory collaboration

Seven distinct sets (n > 12) of state of the art organic photovoltaic devices were prepared by leading research laboratories in a collaboration planned at the Third International Summit on Organic Photovoltaic Stability (ISOS-3). All devices were shipped to DTU and characterized simultaneously up to 1830 h in accordance with established ISOS-3 protocols under three distinct illumination conditions: accelerated full sun simulation; low level indoor fluorescent lighting; and dark storage with daily measurement under full sun simulation. Three nominally identical devices were used in each experiment both to provide an assessment of the homogeneity of the samples and to distribute samples for a variety of post soaking analytical measurements at six distinct laboratories enabling comparison at various stages in the degradation of the devices. Characterization includes current-voltage curves, light beam induced current (LBIC) imaging, dark lock-in thermography (DLIT), photolu minescence (PL), electroluminescence (EL), in situ incident photon-to-electron conversion efficiency (IPCE), time of flight secondary ion mass spectrometry (TOF-SIMS), cross sectional electron microscopy (SEM), UV visible spectroscopy, fluorescence microscopy, and atomic force microscopy (AFM). Over 100 devices with more than 300 cells were used in the study. We present here design of the device sets, results both on individual devices and uniformity of device sets from the wide range of characterization methods applied at different stages of aging under the three illumination conditions. We will discuss how these data can help elucidate the degradation mechanisms as well as the benefits and challenges associated with the unprecedented size of the collaboration

Roadmap on organic–inorganic hybrid perovskite semiconductors and devices

Metal halide perovskites are the first solution processed semiconductors that can compete in their functionality with conventional semiconductors, such as silicon. Over the past several years, perovskite semiconductors have reported breakthroughs in various optoelectronic devices, such as solar cells, photodetectors, light emitting and memory devices, and so on. Until now, perovskite semiconductors face challenges regarding their stability, reproducibility, and toxicity. In this Roadmap, we combine the expertise of chemistry, physics, and device engineering from leading experts in the perovskite research community to focus on the fundamental material properties, the fabrication methods, characterization and photophysical properties, perovskite devices, and current challenges in this field. We develop a comprehensive overview of the current state-of-the-art and offer readers an informed perspective of where this field is heading and what challenges we have to overcome to get to successful commercialization.& nbsp;(C)2021 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license(http://creativecommons.org/licenses/by/4.0/)

An inter-laboratory stability study of roll-to-roll coated flexible polymer solar modules

19 páginas, 16 figuras, 16 tablas.-- El pdf del artículo es la versión pre-print.-- Trabajo presentado al "3rd International Summit on OPV Stability".-- et al.A large number of flexible polymer solar modules comprising 16 serially connected individual cells was prepared at the experimental workshop at Risø DTU. The photoactive layer was prepared from several varieties of P3HT (Merck, Plextronics, BASF and Risø DTU) and two varieties of ZnO (nanoparticulate, thin film) were employed as electron transport layers. The devices were all tested at Risø DTU and the functional devices were subjected to an inter-laboratory study involving the performance and the stability of modules over time in the dark, under light soaking and outdoor conditions. 24 laboratories from 10 countries and across four different continents were involved in the studies. The reported results allowed for analysis of the variability between different groups in performing lifetime studies as well as performing a comparison of different testing procedures. These studies constitute the first steps toward establishing standard procedures for an OPV lifetime characterization.This work was supported by: the Danish Strategic Research Council (DSF2104-07-0022), EUDP(j.nr.64009-0050), PV-ERA-NET (project acronym POLYSTAR),the Spanish Ministry of Science and Innovation, MICINN for the project ENE2008-04373 and CSIC for the PIE-200860I134. Financial support by the Austrian Research Promotion Agency (FFG), the Christian Doppler Research Association (CDG), the Austrian Federal Ministry of Economy, Family and Youth (BMWFJ) and the ISOVOLTAIC Gmb His gratefully acknowledged. Part of this work was supported by the PCCL(ProjectIV-1.02) with in the frame-work of the COMET-program of the Austrian Government. MH, TM, KL and MR would like to thank the Bundesministerium fuer Bildung und Forschung in the frame works of the InnoProfile project (03IP602), the OPEG project(13N9720) and the OPA project (13N9872). HH gratefully acknowledges funding with in the frame of BMBFOPV program. This work was partially supported by the King Abdullah University of Science and Technology and the Department of Energy, by KIST internal research fund under the Contract no. of 2E21831; by the European Commission as part of the Framework 7ICT2009 collaborative project HIFLEX(Grant Agreement no. 248678). RR, MS&HH acknowledge financial support from German Federal Ministry of Education and Research (BMBF)within‘‘Polymer Photovoltaics Processing’’(PPP) project (support code 13N9843).Part of this work was supported by the Victorian Organic Solar Cell Consortium.Peer reviewe

On the stability of a variety of organic photovoltaic devices by IPCE and in situ IPCE analyses – the ISOS-3 inter-laboratory collaboration

status: publishe