The vast bacteriophage population harbors an immense reservoir of genetic information. Almost 2000 phage genomes have been sequenced from phages infecting hosts in the phylum Actinobacteria, and analysis of these genomes reveals substantial diversity, pervasive mosaicism, and novel mechanisms for phage replication and lysogeny. Here, we describe the isolation and genomic characterization of 46 phages from environmental samples at various geographic locations in the U.S. infecting a single Arthrobacter sp. strain. These phages include representatives of all three virion morphologies, and Jasmine is the first sequenced podovirus of an actinobacterial host. The phages also span considerable sequence diversity, and can be grouped into 10 clusters according to their nucleotide diversity, and two singletons each with no close relatives. However, the clusters/singletons appear to be genomically well separated from each other, and relatively few genes are shared between clusters. Genome size varies from among the smallest of siphoviral phages (15,319 bp) to over 70 kbp, and G+C contents range from 45–68%, compared to 63.4% for the host genome. Although temperate phages are common among other actinobacterial hosts, these Arthrobacter phages are primarily lytic, and only the singleton Galaxy is likely temperate.

Changes in the gravitational vector by postural changes or weightlessness induce fluid shifts impacting ocular hemodynamics and regional pressures. This investigation explores the impact of changes in direction of the gravitational vector on intraocular pressure (IOP), mean arterial pressure at eyelevel (MAPeye), and ocular perfusion pressure (OPP), which is critical for ocular health. Thirteen subjects underwent 360° of tilt (including both prone and supine positions) at 15º increments. At each angle, steady-state IOP and MAPeye were measured and OPP calculated as MAPeye-IOP. Experimental data were compared to a 6-compartment lumped parameter model of the eye. Mean IOP, MAPeye, and OPP significantly increased from 0º supine to 90º head down tilt (HDT) by 20.7±1.7 mmHg (ᵅD; < 0.001), 38.5±4.1 mmHg (ᵅD; < 0.001), and 17.4±3.2 mmHg (ᵅD; <0.001), respectively. Head up tilt (HUT) significantly decreased OPP by 16.5±2.5 mmHg (ᵅD; < 0.001). IOP was significantly higher in prone vs. supine position for much of the tilt range. Our study indicates that OPP is highly gravitationally dependent. Specifically, data show that MAPeye is more gravitationally dependent than IOP, thus causing OPP to increase during HDT and to decrease during HUT. Additionally, IOP was elevated in prone position compared to supine position due to the additional hydrostatic column between the base of the rostral globe to the mid-caudal plane, supporting the notion that hydrostatic forces play an important role in ocular hemodynamics. Changes in OPP as a function of changes in gravitational stress and/or weightlessness may play a role in the pathogenesis of spaceflight-associated neuro-ocular syndrome.

The COVID‐19 pandemic has produced critical shortages of ventilators worldwide. There is an unmet need for rapidly deployable, emergency‐use ventilators with sufficient functionality to manage COVID‐19 patients with severe acute respiratory distress syndrome. Here, we show the development and validation of a simple, portable and low‐cost ventilator that may be rapidly manufactured with minimal susceptibility to supply chain disruptions. This single‐mode continuous, mandatory, closed‐loop, pressure‐controlled, time‐terminated emergency ventilator offers robust safety and functionality absent in existing solutions to the ventilator shortage. Validated using certified test lungs over a wide range of compliances, pressures, volumes and resistances to meet U.S. Food and Drug Administration standards of safety and efficacy, an Emergency Use Authorization is in review for this system. This emergency ventilator could eliminate controversial ventilator rationing or splitting to serve multiple patients. All design and validation information is provided to facilitate ventilator production even in resource‐limited settings.

The ability to respond rapidly to changes in oxygen tension is critical for many forms of life. Challenges to oxygen homeostasis, specifically in the contexts of evolutionary biology and biomedicine, provide important insights into mechanisms of hypoxia adaptation and tolerance. Here we synthesize findings across varying time domains of hypoxia in terms of oxygen delivery, ranging from early animal to modern human evolution and examine the potential impacts of environmental and clinical challenges through emerging multi-omics approaches. We discuss how diverse animal species have adapted to hypoxic environments, how humans vary in their responses to hypoxia (i.e., in the context of high-altitude exposure, cardiopulmonary disease, and sleep apnea), and how findings from each of these fields inform the other and lead to promising new directions in basic and clinical hypoxia research.

OBJECTIVE To evaluate the effect of soccer heading on intracranial pressure (ICP) in trained athletes. METHODS Eight subjects (all male, 21.7±1.7 years) were recruited from the UC San Diego soccer team. ICP and cardiovascular variables were recorded before and after 6 repeats of heading a soccer ball kicked from 35 yards away, into a goal. ICP was estimated non‐invasively from acoustical evoked tympanic membrane displacement (Vm), where a more negative volume displacement is correlated with higher ICP. Mean arterial pressure (MAP), heart rate (HR; Nexfin, Netherlands), and ICP were recorded in three different postures, 15° head up tilt (HUT), 0° supine, −15° head down tilt (HDT), in a randomized order. RESULTS Mean Vm at 15° HUT was 37.81±133.21 nL at baseline and −20.82±158.27 nL immediately post soccer heading (P=0.0482, paired t test), analogous to an increased ICP. At 0° supine, mean Vm was −46.19±178.50 nL at baseline and −84.27±183.55 nL after impact (P=0.0321, paired t test). At −15° HDT, mean Vm was −148.48±196.07 nL at baseline and −187.02±186.19 nL immediately post soccer heading (P=0.1176, paired t test). MAP and HR did not significantly change between the baseline and post soccer heading measurements. DISCUSSION After repeated soccer ball heading, ICP significantly increased at 15° HUT and 0° supine, while ICP at −15° HDT, MAP and HR did not significantly change. The relative increase in ICP associated with HDT is comparable to previously described trends. Although the measurement technique currently employed does not provide an absolute ICP baseline, the technique has been established as useful in evaluating relative changes. Under that interpretation, these results reflect what may be an elevated ICP related to soccer heading impacts. Accordingly, the results of this study suggest a potential health risk of participation in head contact sports. Support or Funding Information NASA (80NSSC19K0020) and Novo Nordic Foundation (NNF16OC0019196) Soccer Heading Increases Intracranial Pressure at Head Up Tilt and Supine Positions Volume displacement of tympanic membrane (Vm), measured non‐invasively from acoustical evoked tympanic membrane displacement, indicated an increase in intracranial pressure (ICP) after soccer heading at 15° head up tilt (HUT) and 0° supine (n = 8, paired t test, *P < 0.05). No significant increase in ICP at −15° head down tilt (HDT) was observed after soccer heading.