Cellular cognition: How single cells learn using non-neural networks.

Single cells can perform surprisingly complex behaviors and computations, including primitive forms of learning like habituation. New work highlighted here uses mathematical modeling to show that relatively simple biochemical networks can recapitulate many features of habituation in animals.

Estimating lives saved and serious injuries reduced by bicycle helmet use in Colorado, 2006-2014.

Using the methodology developed by the National Highway Traffic Safety Administration (NHTSA) for motorcyclists, this paper estimates bicycle helmet effectiveness factors (HEFs), defined as the percentage greater chance that a helmeted bicyclist will avoid a fatality or serious injury relative to a non-wearer. We analyse reported motor vehicle-bicycle collisions in Colorado between 2006 and 2014. We conclude that NHTSA's motorcycle HEF methodology did not provide reasonable results given underreporting of low-severity collisions of helmeted bicyclists.

Sodium zirconium cyclosilicate treatment and rates of emergency interventions for hyperkalaemia: a propensity-score weighted case-control study.

Background: Sodium zirconium cyclosilicate (SZC) reduces serum potassium in patients with chronic hyperkalaemia in clinical trials, but its role in the emergency treatment of hyperkalaemia is unproven. We hypothesized that SZC use for emergent hyperkalaemia would be associated with a reduction in rates of emergency interventions for hyperkalaemia.

Methods: This was a single-centre, propensity score-weighted case-control study of patients admitted with hyperkalaemia to a specialist renal centre.

Fishnet mesh of centrin-Sfi1 drives ultrafast calcium-activated contraction of the giant cell .

is a unicellular ciliate capable of contracting to a quarter of its body length in less than five milliseconds. When measured as fractional shortening, this is an order of magnitude faster than motion powered by actomyosin. Myonemes, which are protein networks found near the cortex of many protists, are believed to power contraction.

Voltage-Controlled Synthesis of Higher Harmonics in Hybrid Josephson Junction Circuits.

We report measurements of the current-phase relation of two voltage-controlled semiconductor-superconductor hybrid Josephson junctions (JJs) in series. The two hybrid junctions behave similar to a single-mode JJ with effective transparency determined by the ratio of Josephson coupling strengths of the two junctions. Gate-voltage control of Josephson coupling (measured from switching currents) allows tuning of the harmonic content from sinusoidal, for asymmetric tuning, to highly nonsinusoidal, for symmetric tuning.

Phylogeny, morphology, and behavior of the new ciliate species .

The study of evolution at the cellular level traditionally has focused on the evolution of metabolic pathways, endomembrane systems, and genomes, but there has been increasing interest in evolution of more complex cellular structures and behaviors, particularly in the eukaryotes. Ciliates have major advantages for such studies due to their easily visible surface patterning and their dramatic and complex behaviors that can be easily analyzed. Among the ciliates, the genus epitomizes the features that are useful for studying evolution: they are widespread in freshwater environments, easy to visualize because of their large size, and capable of complex behaviors such as learning, decision-making, and phototaxis.

Ichthyosporea: a window into the origin of animals.

Ichthyosporea is an underexplored group of unicellular eukaryotes closely related to animals. Thanks to their phylogenetic position, genomic content, and development through a multinucleate coenocyte reminiscent of some animal embryos, the members of Ichthyosporea are being increasingly recognized as pivotal to the study of animal origins. We delve into the existing knowledge of Ichthyosporea, identify existing gaps and discuss their life cycles, genomic insights, development, and potential to be model organisms.

Extraordinary model systems for regeneration.

Regeneration is the remarkable phenomenon through which an organism can regrow lost or damaged parts with fully functional replacements, including complex anatomical structures, such as limbs. In 2019, Development launched its 'Model systems for regeneration' collection, a series of articles introducing some of the most popular model organisms for studying regeneration in vivo. To expand this topic further, this Perspective conveys the voices of five expert biologists from the field of regenerative biology, each of whom showcases some less well-known, but equally extraordinary, species for studying regeneration.

as a model system to study cilia and flagella using genetics, biochemistry, and microscopy.

The unicellular green alga, i, has played a central role in discovering much of what is currently known about the composition, assembly, and function of cilia and flagella. combines excellent genetics, such as the ability to grow cells as haploids or diploids and to perform tetrad analysis, with an unparalleled ability to detach and isolate flagella in a single step without cell lysis. The combination of genetics and biochemistry that is possible in has allowed many of the key components of the cilium to be identified by looking for proteins that are missing in a defined mutant.

Transcatheter Interventions in Adult Congenital Heart Disease.

Congenital heart disease (CHD) is the most common congenital birth defect with an incidence of 1 in 100. Current survival to adulthood is expected in 9 out of 10 children with severe CHD as the diagnostic, interventional, and surgical success improves. The adult CHD (ACHD) population is increasingly diverse, reflecting the broad spectrum of CHD and evolution of surgical techniques to improve survival.

Behavioral and cortical arousal from sleep, muscimol-induced coma, and anesthesia by direct optogenetic stimulation of cortical neurons.

The cerebral cortex is widely considered part of the neural substrate of consciousness, but direct causal evidence is missing. Here, we tested in mice whether optogenetic activation of cortical neurons in posterior parietal cortex (PtA) or medial prefrontal cortex (mPFC) is sufficient for arousal from three behavioral states characterized by progressively deeper unresponsiveness: sleep, a coma-like state induced by muscimol injection in the midbrain, and deep sevoflurane-dexmedetomidine anesthesia. We find that cortical stimulation always awakens the mice from both NREM sleep and REM sleep, with PtA requiring weaker/shorter light pulses than mPFC.

Physical Forces in Regeneration of Cells and Tissues.

The ability to regenerate after the loss of a part is a hallmark of living systems and occurs at both the tissue and organ scales, but also within individual cells. Regeneration entails many processes that are physical and mechanical in nature, including the closure of wounds, the repositioning of material from one place to another, and the restoration of symmetry following perturbations. However, we currently know far more about the genetics and molecular signaling pathways involved in regeneration, and there is a need to investigate the role of physical forces in the process.

Modeling homologous chromosome recognition via nonspecific interactions.

In many organisms, most notably , homologous chromosomes associate in somatic cells, a phenomenon known as somatic pairing, which takes place without double strand breaks or strand invasion, thus requiring some other mechanism for homologs to recognize each other. Several studies have suggested a "specific button" model, in which a series of distinct regions in the genome, known as buttons, can associate with each other, mediated by different proteins that bind to these different regions. Here, we use computational modeling to evaluate an alternative "button barcode" model, in which there is only one type of recognition site or adhesion button, present in many copies in the genome, each of which can associate with any of the others with equal affinity.

Exploring the full range of N⋯I⋯X halogen-bonding interactions within a single compound using pressure.

The response of the trimethylammonium-iodinechloride and diiodide (TMA-ICl/I) crystal structures have been examined under high pressure using neutron powder diffraction. TMA-ICl exhibits impressive pressure-driven electronic flexibility, where the N⋯I-Cl interactions progressively encompass all the distances represented in analogous structures recorded in the Cambridge Structural Database. Comparison with the TMA-I complex reveals that this flexibility is owed to the electronegativity of the chlorine atom which induces increased distortion of the iodine electron cloud.

Cell motility: Bioelectrical control of behavior without neurons.

Single cells are capable of remarkably sophisticated, sometimes animal-like, behaviors. New work demonstrates bioelectric control of motility through the differential regulation of appendage movements in a unicellular organism that walks across surfaces using leg-like bundles of cilia.

Early Experience and Lessons Learned Using Implanted Hemodynamic Monitoring in Patients With Fontan Circulation.

Background: Data on the use of implanted hemodynamic monitoring (IHM) in patients with Fontan circulation are limited. This study reports our experience using the CardioMEMS HF system in adults with Fontan circulation.

Methods And Results: This single-center, retrospective study evaluated heart failure hospitalizations, procedural complications, and device-related complications in patients with Fontan circulation referred for IHM placement (2015-2022).

Integrated information theory (IIT) 4.0: Formulating the properties of phenomenal existence in physical terms.

This paper presents Integrated Information Theory (IIT) 4.0. IIT aims to account for the properties of experience in physical (operational) terms.