The general functions of lymphatic vessels in fluid transport and immunosurveillance are well recognized. However, accumulating evidence indicates that lymphatic vessels play active and versatile roles in a tissue- and organ-specific manner during homeostasis and in multiple disease processes. This Review discusses recent advances to understand previously unidentified functions of adult mammalian lymphatic vessels, including immunosurveillance and immunomodulation upon pathogen invasion, transport...
Tuning a semiconductor to function as a fast proton conductor is an emerging strategy in the rapidly developing field of proton ceramic fuel cells (PCFCs). The key challenge for PCFC researchers is to formulate the proton-conducting electrolyte with conductivity above 0.1 siemens per centimeter at low temperatures (300 to 600°C). Here we present a methodology to design an enhanced proton conductor by means of a NaxCoO2/CeO2 semiconductor heterostructure, in which a field-induced metallic state at...
Muscarinic toxins (MTs) are natural toxins produced by mamba snakes that primarily bind to muscarinic acetylcholine receptors (MAChRs) and modulate their function. Despite their similar primary and tertiary structures, MTs show distinct binding selectivity toward different MAChRs. The molecular details of how MTs distinguish MAChRs are not well understood. Here, we present the crystal structure of M1AChR in complex with MT7, a subtype-selective anti-M1AChR snake venom toxin. The structure reveals...
Immunodeficiency often coincides with hyperactive immune disorders such as autoimmunity, lymphoproliferation, or atopy, but this coincidence is rarely understood on a molecular level. We describe five patients from four families with immunodeficiency coupled with atopy, lymphoproliferation, and cytokine overproduction harboring mutations in NCKAP1L, which encodes the hematopoietic-specific HEM1 protein. These mutations cause the loss of the HEM1 protein and the WAVE regulatory complex (WRC) or disrupt...
Engineering strong interactions between quantum systems is essential for many phenomena of quantum physics and technology. Typically, strong coupling relies on short-range forces or on placing the systems in high-quality electromagnetic resonators, which restricts the range of the coupling to small distances. We used a free-space laser beam to strongly couple a collective atomic spin and a micromechanical membrane over a distance of 1 meter in a room-temperature environment. The coupling is highly...
How animals navigate over large-scale environments remains a riddle. Specifically, it is debated whether animals have cognitive maps. The hallmark of map-based navigation is the ability to perform shortcuts, i.e., to move in direct but novel routes. When tracking an animal in the wild, it is extremely difficult to determine whether a movement is truly novel because the animal’s past movement is unknown. We overcame this difficulty by continuously tracking wild fruit bat pups from their very first...
The dentitions of extant fishes and land vertebrates vary in both pattern and type of tooth replacement. It has been argued that the common ancestral condition likely resembles the nonmarginal, radially arranged tooth files of arthrodires, an early group of armoured fishes. We used synchrotron microtomography to describe the fossil dentitions of so-called acanthothoracids, the most phylogenetically basal jawed vertebrates with teeth, belonging to the genera Radotina, Kosoraspis, and Tlamaspis (from...
Contact area-dependent cell communication and the morphological invariance of ascidian embryogenesis
Marine invertebrate ascidians display embryonic reproducibility: Their early embryonic cell lineages are considered invariant and are conserved between distantly related species, despite rapid genomic divergence. Here, we address the drivers of this reproducibility. We used light-sheet imaging and automated cell segmentation and tracking procedures to systematically quantify the behavior of individual cells every 2 minutes during Phallusia mammillata embryogenesis. Interindividual reproducibility...
Reversing brain aging may be possible through systemic interventions such as exercise. We found that administration of circulating blood factors in plasma from exercised aged mice transferred the effects of exercise on adult neurogenesis and cognition to sedentary aged mice. Plasma concentrations of glycosylphosphatidylinositol (GPI)–specific phospholipase D1 (Gpld1), a GPI-degrading enzyme derived from liver, were found to increase after exercise and to correlate with improved cognitive function...
Topological semimetals feature protected nodal band degeneracies characterized by a topological invariant known as the Chern number (C). Nodal band crossings with linear dispersion are expected to have at most , which sets an upper limit to the magnitude of many topological phenomena in these materials. Here, we show that the chiral crystal palladium gallium (PdGa) displays multifold band crossings, which are connected by exactly four surface Fermi arcs, thus proving that they carry the maximal Chern...
Seven decades of research on the "cognitive map," the allocentric representation of space, have yielded key neurobiological insights, yet field evidence from free-ranging wild animals is still lacking. Using a system capable of tracking dozens of animals simultaneously at high accuracy and resolution, we assembled a large dataset of 172 foraging Egyptian fruit bats comprising >18 million localizations collected over 3449 bat-nights across 4 years. Detailed track analysis, combined with translocation...
Historically, sea ice loss in the Arctic Ocean has promoted increased phytoplankton primary production because of the greater open water area and a longer growing season. However, debate remains about whether primary production will continue to rise should sea ice decline further. Using an ocean color algorithm parameterized for the Arctic Ocean, we show that primary production increased by 57% between 1998 and 2018. Surprisingly, whereas increases were due to widespread sea ice loss during the first...
France has been heavily affected by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic and went into lockdown on 17 March 2020. Using models applied to hospital and death data, we estimate the impact of the lockdown and current population immunity. We find that 2.9% of infected individuals are hospitalized and 0.5% of those infected die (95% credible interval: 0.3 to 0.9%), ranging from 0.001% in those under 20 years of age to 8.3% in those 80 years of age or older. Across...
Cerebrospinal fluid (CSF) is a vital liquid, providing nutrients and signaling molecules and clearing out toxic by-products from the brain. The CSF is produced by the choroid plexus (ChP), a protective epithelial barrier that also prevents free entry of toxic molecules or drugs from the blood. Here, we establish human ChP organoids with a selective barrier and CSF-like fluid secretion in self-contained compartments. We show that this in vitro barrier exhibits the same selectivity to small molecules...
As coronavirus disease 2019 (COVID-19) is rapidly spreading across the globe, short-term modeling forecasts provide time-critical information for decisions on containment and mitigation strategies. A major challenge for short-term forecasts is the assessment of key epidemiological parameters and how they change when first interventions show an effect. By combining an established epidemiological model with Bayesian inference, we analyzed the time dependence of the effective growth rate of new infections....
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