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Closure of the Central American Seaway (CAS) and hydrology of the Caribbean Sea triggered Northern Hemisphere Glaciation and played an important role in the Pliocene to modern‐day climate re‐establishing the deep and surface ocean currents. New data on Mn/Ca obtained with femtosecond laser ablation inductively coupled plasma mass spectrometry on well‐preserved tests of the epibenthic foraminifer Cibicidoides wuellerstorfi and infaunal C. mundulus contribute to the interpretation of paleoenvironmental conditions of the Caribbean Sea between 5.2 and 2.2 Ma (million years) across the closure of the CAS. Hydrothermal activity at the Lesser Antilles may be a primary source of Mn in the well‐oxygenated Plio‐Pleistocene Caribbean Sea. Incorporation of Mn in the benthic foraminifer shell carbonate is assumed to be affected by surface ocean nutrient cycling, and may hence be an indicator of paleoproductivity., Plain Language Summary: The closure of the Panama Isthmus caused the expansion of ice sheets in the Northern Hemisphere and changed the water current dynamics and climate in the Caribbean Sea since the Pliocene (∼5.3 million years ago). New Mn/Ca data measured using femtosecond laser ablation inductively coupled plasma mass spectrometry on the deep‐sea benthic foraminifer species Cibicidoides wuellerstorfi and Cibicidoides mundulus help us understand past environmental conditions of the Caribbean Sea prevailed between 5.2 and 2.2 million years ago. While manganese might be sourced from the surrounding hydrothermal vents, its incorporation in the foraminifer shell carbonate might be related to nutrient cycling and may indicate past biological productivity in the ocean., Key Points: Femtosecond‐laser ablation inductively coupled plasma mass spectrometry provides a new approach on distinguishing Mn of the ontogenetic shell calcite from Mn of the authigenic coatings. Ontogenetic Mn within the foraminifer shell calcite may result from the regional nutrient cycle. Mn in the deep eastern Caribbean Sea may mainly derive from hydrothermal sources along the Antilles Island Arc., MPIC, https://doi.org/10.17632/bps7nw7922.1

Calcareous foraminifer shells (tests) represent one of the most important archives for paleoenvironmental and paleoclimatic reconstruction. To develop a mechanistic understanding of the relationship between environmental parameters and proxy signals, knowledge of the fundamental processes operating during foraminiferal biomineralization is essential. Here, we apply microscopic and diffraction‐based methods to address the crystallographic and hierarchical structure of the test wall of different hyaline foraminifer species. Our results show that the tests are constructed from micrometer‐scale oriented mesocrystals built of nanometer‐scale entities. Based on these observations, we propose a mechanistic extension to the biomineralization model for hyaline foraminifers, centered on the formation and assembly of units of metastable carbonate phases to the final mesocrystal via a non‐classical particle attachment process, possibly facilitated by organic matter. This implies the presence of metastable precursors such as vaterite or amorphous calcium carbonate, along with phase transitions to calcite, which is relevant for the mechanistic understanding of proxy incorporation in the hyaline foraminifers., Plain Language Summary: Foraminifers are single celled marine organisms typically half a millimeter in size, which form shells made of calcium carbonate. During their life, the chemical composition of their shells records environmental conditions. By analyzing fossil shells, past conditions can be reconstructed to understand ancient oceans and climate change. To do that correctly, we need to know exactly how foraminifers form their shell. We find that foraminifers build micrometer‐sized mesocrystals which are made of smaller building blocks. This means that the smallest building blocks form first and assemble to form a larger grain, which is oriented in a specific direction. To align all the building blocks, it is possible that they are first unstable and undergo transformation on assembly, during which their composition may change. By understanding and quantifying this process, the composition of the final fossil shell may be understood, ultimately leading to more reliable reconstructions of past environmental change., Key Points: Hyaline foraminiferal shells are built of micrometer sized mesocrystalline units. Biomineralization likely includes the formation and assembly of nanoparticles. Nanometer sized units suggest non‐classical crystal growth., https://doi.org/10.17617/3.D7HN3I

The role of aerosolized SARS-CoV-2 viruses in airborne transmission of COVID-19 is debated. The transmitting aerosol particles are generated through the breathing and vocalization by infectious subjects. Some authors state that this represents the dominant route of spreading, while others dismiss the option. Public health organizations generally categorize it as a secondary transmission pathway. Here we present a simple, easy-to-use spreadsheet model to estimate the infection risk for different indoor environments, constrained by published data on human aerosol emissions, SARS-CoV-2 viral loads, infective dose and other parameters. We evaluate typical indoor settings such as an office, a classroom, a choir practice room and reception/party environments. These are examples, and the reader is invited to use the algorithm for alternative situations and assumptions. Our results suggest that aerosols from highly infective subjects can effectively transmit COVID-19 in indoor environments. This “highly infective” category represents approximately twenty percent of the patients tested positive for SARS-CoV-2. We find that “super infective” subjects, representing the top five to ten percent of positive-tested ones, plus an unknown fraction of less, but still highly infective, high aerosol-emitting subjects, may cause COVID-19 clusters (>10 infections), e.g. in classrooms, during choir singing and at receptions. The highly infective ones also risk causing such events at parties, for example. In general, active room ventilation and the ubiquitous wearing of face masks (i.e. by all subjects) may reduce the individual infection risk by a factor of five to ten, similar to high-volume HEPA air filtering. The most effective mitigation measure studied is the use of high-quality masks, which can drastically reduce the indoor infection risk through aerosols., medRxiv

Deutschland und die Weltgemeinschaft haben sich im Pariser Klimaabkommen 2015 dazu verpflichtet, die menschengemachte globale Erwärmung der Erde auf weniger als 2°C zu beschränken. Dieses Ziel ist nur noch zu erreichen, wenn sofort sowohl nationale wie auch internationale Vereinbarungen eingehalten werden. In der Ad-hoc-Stellungnahme „Klimaziele 2030: Wege zu einer nachhaltigen Reduktion der CO₂-Emissionen“ fordert die Nationale Akademie der Wissenschaften Leopoldina deshalb einen unmittelbaren Transformationsschub und beschreibt Sofortmaßnahmen zum Schutz des Klimas, die schnell sozialverträglich und innovationsfördernd Wirkung entfalten können. Die Leopoldina unterstützt die in aktuellen Expertengutachten enthaltene Forderung nach einem einheitlichen und sektorenübergreifenden Preis für Treibhausgasemissionen. Der anfängliche CO₂-Preis müsse dabei erheblich höher liegen als der aktuelle Preis im europäischen Emissionshandel, der momentan bei 25 Euro/t CO₂ liegt. Zudem solle der Preis in den kommenden Jahren schrittweise steigen. Die Politik sei gefordert, die gewählte CO₂-Bepreisung regelmäßig zu überprüfen und bei Bedarf nachzujustieren. Das Instrument der CO₂-Bepreisung müsse als unverrückbare klimapolitische Strategie erkennbar sein. In der Stellungnahme wird darauf hingewiesen, dass ein CO₂-Preis alleine jedoch nicht ausreicht, um die Klimaziele 2030 zu erreichen. Dafür sollten unter anderem die Einnahmen aus der CO₂-Bepreisung transparent reinvestiert werden in eine kohlenstoffarme Infrastruktur und Allgemeingüter, in die relative Absenkung des Strompreises und in den sozialen Ausgleich in Form einer „Klimadividende“. Ziel sei es, Anreize für ein klimaschützendes Wirtschaften und Verhalten zu setzen. Klimaschützendes Verhalten könne dann sogar zu einem finanziellen Gewinn für Konsumentinnen und Konsumenten führen, vor allem bei niedrigeren Einkommensgruppen. Eine wirksame Bepreisung von CO₂ werde einen früheren Kohleausstieg wahrscheinlicher machen, so die Autorinnen und Autoren der Stellungnahme. Technisch sei dies in Deutschland möglich, vor allem gemeinsam mit den europäischen Partnern. Voraussetzungen seien Investitionen in erneuerbare Energien, in ein modernes Stromnetz und in Speichertechnologien (Power-to-gas, Batterien, Power-to-liquid). Im Bereich Verkehr, der rund 20 Prozent der CO₂-Emissionen verursacht, wird in der Stellungnahme eine massive Elektrifizierung empfohlen. Der öffentliche Personennahverkehr (ÖPNV), der Schienenfernverkehr und der Gütertransport auf der Schiene müssten erheblich ausgebaut und qualitativ verbessert werden. Hinsichtlich privater Pkw sei die Umstellung auf stark hybridisierte und batterieelektrische Fahrzeuge ein wirkungsvoller, kurzfristiger Hebel. In den Städten solle dem ÖPNV, Fahrradverkehr sowie Fußgängerinnen und Fußgängern Priorität eingeräumt werden. Die Autorinnen und Autoren der Stellungnahme weisen zudem darauf hin, dass die aktuellen Transportkosten im Güterverkehr den Umweltverbrauch nicht hinreichend berücksichtigen. Sie empfehlen den internationalen Flug- und Schiffsverkehr über entsprechende Abkommen mit einem CO₂-Preis zu belegen. Die Mitgliedstaaten der Europäischen Union haben zur Beschränkung des Klimawandels konkrete und rechtlich verbindliche Ziele für 2020 und 2030 vereinbart und für einige Bereiche länderspezifische Zielvorgaben definiert. Nach heutigem Stand wird Deutschland die Ziele für 2020 nicht erreichen. Die Bundesregierung hat bisher im Klimaschutzplan 2050 verschiedene Maßnahmen vorgesehen und Reduktionsziele für einzelne Sektoren definiert. Demnach soll der durchschnittliche CO₂-Ausstoß bis spätestens 2030 für alle Sektoren zusammen um mindestens 55% gegenüber 1990 sinken. Die nationale Klimapolitik braucht dazu jetzt eine konsequentere, transparentere und zügigere Umsetzungsstrategie, so die Wissenschaftlerinnen und Wissenschaftler. Sie müsse Bürgerinnen und Bürgern, Städten und ländlichen Regionen sowie der Wirtschaft insgesamt Planungssicherheit geben und schnell Weichen stellen, um den immer teureren und ungerechten „Business as usual-Pfad“ zu verlassen und auf den Pfad einer nachhaltigen Entwicklung zu gelangen. Mit dem derzeitigen Rückenwind aus der Bevölkerung habe die Politik jetzt die einmalige Chance, die Herausforderung zu meistern.

© 2019 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society Chronic respiratory diseases are among the leading causes of mortality worldwide, with the major contributor, chronic obstructive pulmonary disease (COPD) accounting for approximately 3 million deaths annually. Frequent acute exacerbations (AEs) of COPD (AECOPD) drive clinical and functional decline in COPD and are associated with accelerated loss of lung function, increased mortality, decreased health-related quality of life and significant economic costs. Infections with a small subgroup of pathogens precipitate the majority of AEs and consequently constitute a significant comorbidity in COPD. However, current pharmacological interventions are ineffective in preventing infectious exacerbations and their treatment is compromised by the rapid development of antibiotic resistance. Thus, alternative preventative therapies need to be considered. Pathogen adherence to the pulmonary epithelium through host receptors is the prerequisite step for invasion and subsequent infection of surrounding structures. Thus, disruption of bacterial-host cell interactions with receptor antagonists or modulation of the ensuing inflammatory profile present attractive avenues for therapeutic development. This review explores key mediators of pathogen-host interactions that may offer new therapeutic targets with the potential to prevent viral/bacterial-mediated AECOPD. There are several conceptual and methodological hurdles hampering the development of new therapies that require further research and resolution.

Understanding oceanic cadmium (Cd) cycling is paramount due to its micronutrient-like behavior in seawater, which has been inferred from its similarity to phosphate (PO4) cycling. Cadmium concentrations follow a nutrient-like consumption-regeneration cycle in the top of the water column and are mainly controlled by water mass mixing and circulation in the deep ocean. However, an additional scavenging mechanism through cadmium sulfide (CdS) precipitates, occurring within sinking biogenic particles in oxygen deficient zones (ODZ), has been proposed. In this study, we report Cd stable isotope and concentration data for seven vertical seawater profiles sampled during GEOTRACES cruise GA08 in the northern Cape and Angola Basins, which feature a significant ODZ along their eastern margins. Outside the ODZ, Cd cycling is similar to that previously reported for the South Atlantic. While water mass mixing largely controls deep ocean Cd isotope signatures, Cd isotope fractionation in surface waters can be modeled as an open system at steady state buffered by organic ligand complexation. In the ODZ, stronger Cd depletion relative to PO4 is associated with a shift in δ114Cd toward heavier values, which is indicative of CdS precipitation. Our interpretation is supported by experimental CdS precipitation data and a size-resolved particle model involving bacterial sulfate reduction as a precursor of CdS. Our estimates of the CdS flux to the seafloor (107 to 109 mol/yr) indicate that CdS precipitation is a significant process of Cd removal and constitutes a nonnegligible Cd sink that needs to be better quantified by Cd isotope analyses of marine sediments.

© 2018, Springer Nature Switzerland AG. Chronic obstructive pulmonary disease (COPD) and lung cancer are major lung diseases affecting millions worldwide. Both diseases have links to cigarette smoking and exert a considerable societal burden. People suffering from COPD are at higher risk of developing lung cancer than those without, and are more susceptible to poor outcomes after diagnosis and treatment. Lung cancer and COPD are closely associated, possibly sharing common traits such as an underlying genetic predisposition, epithelial and endothelial cell plasticity, dysfunctional inflammatory mechanisms including the deposition of excessive extracellular matrix, angiogenesis, susceptibility to DNA damage and cellular mutagenesis. In fact, COPD could be the driving factor for lung cancer, providing a conducive environment that propagates its evolution. In the early stages of smoking, body defences provide a combative immune/oxidative response and DNA repair mechanisms are likely to subdue these changes to a certain extent; however, in patients with COPD with lung cancer the consequences could be devastating, potentially contributing to slower postoperative recovery after lung resection and increased resistance to radiotherapy and chemotherapy. Vital to the development of new-targeted therapies is an in-depth understanding of various molecular mechanisms that are associated with both pathologies. In this comprehensive review, we provide a detailed overview of possible underlying factors that link COPD and lung cancer, and current therapeutic advances from both human and preclinical animal models that can effectively mitigate this unholy relationship.