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BAR domains are dimeric protein modules that sense, induce, and stabilize lipid membrane curvature. Here, we show that membrane curvature sensing (MCS) directs cellular localization and function of the BAR domain protein PICK1. In PICK1, and the homologous proteins ICA69 and arfaptin2, we identify an amphipathic helix N-terminal to the BAR domain that mediates MCS. Mutational disruption of the helix in PICK1 impaired MCS without affecting membrane binding per se. In insulin-producing INS-1E cells, super-resolution microscopy revealed that disruption of the helix selectively compromised PICK1 density on insulin granules of high curvature during their maturation. This was accompanied by reduced hormone storage in the INS-1E cells. In Drosophila, disruption of the helix compromised growth regulation. By demonstrating size-dependent binding on insulin granules, our finding highlights the function of MCS for BAR domain proteins in a biological context distinct from their function, e.g., at the plasma membrane during endocytosis.

One of the Juno magnetometer investigation's star cameras was configured to search for unidentified objects during Juno's transit en route to Jupiter. This camera detects and registers luminous objects to magnitude 8. Objects persisting in more than five consecutive images and moving with an apparent angular rate of between 2 and 18,000 arcsec/s were recorded. Among the objects detected were a small group of objects tracked briefly in close proximity to the spacecraft. The trajectory of these objects demonstrates that they originated on the Juno spacecraft, evidently excavated by micrometeoroid impacts on the solar arrays. The majority of detections occurred just prior to and shortly after Juno's transit of the asteroid belt. This rather novel detection technique utilizes the Juno spacecraft's prodigious 60 m2of solar array as a dust detector and provides valuable information on the distribution and motion of interplanetary (>μm sized) dust. The Juno magnetometer investigation uses star cameras co‐located with the magnetic sensors at the outer end of one of Juno's solar arrays. These cameras compare images with an onboard star catalog to determine the orientation of the sensors in inertial space. They also serendipitously recorded multiple images of small particles excavated from the spacecraft by high‐velocity dust impacts. We trace their trajectories back in time to demonstrate that they evolved from the spacecraft. This allows us to use the vast collecting area of Juno's solar arrays (60 m2) as a novel dust detector, sensitive to particles with a mass range never before measured in situ. Star cameras included on the Juno spacecraft payload as part of the magnetometer investigation identified and tracked small objects in close proximity to the spacecraftThe tracked objects are identified as submillimeter particles excavated from the spacecraft, liberated by impact of interplanetary dust particles on the spacecraft solar arraysThe number and timing of such impacts provide useful information about the distribution, sources, and sinks of interplanetary dust in the solar system.

Rapid blood loss with circulatory shock is dangerous for the preterm infant as cardiac output and oxygen-carrying capacity are simultaneously imperilled. This requires prompt restoration of circulating blood volume with emergency transfusion. It is recommended that clinicians use both clinical and laboratory responses to guide transfusion requirements in this situation.For preterm infants with anemia of prematurity, it is recommended that clinicians use a restrictive algorithm from one of two recently published clinical trials.Transfusion outside these algorithms in very preterm infants is not evidence-based and is actively discouraged.

Patients requiring hemodialysis access creation often have significant comorbid conditions which may impact access maturation. Underlying cardiac dysfunction likely plays an important role in the maturation of arteriovenous fistulae (AVF). The effect of specific parameters of cardiac function on successful AVF creation has not previously been explored.

Aims.We calculate the dust emission expected at 3.43 and 3.53 $\mu{\rm m}$if meteoritic (i.e. hydrogenated) nanodiamonds are responsible for most of the far-UV break observed in quasars.

Context.Current knowledge suggests that the dust-driven wind scenario provides a realistic framework for understanding mass loss from C-rich AGB stars. For M-type objects, however, recent detailed models demonstrate that radiation pressure on silicate grains is not sufficient to drive the observed winds, contrary to previous expectations.

Local three-dimensional shearing box simulations of the compressible coupled dust-gas equations are used in the fluid approximation to study the evolution of different initial vortex configurations in a protoplanetary disc and their dust-trapping capabilities. The initial conditions for the gas are derived from an analytic solution to the compressible Euler equation and the continuity equation. The solution is valid if there is a vacuum outside the vortex. In the simulations the vortex is either embedded in a hot corona, or it is extended in a cylindrical fashion in the vertical direction. Both configurations are found to survive for at least one orbit and lead to accumulation of dust inside the vortex. This confirms earlier findings that dust accumulates in anticyclonic vortices, indicating that this is a viable mechanism for planetesimal formation.

This paper develops a tractable general equilibrium model to analyze the effect of credit constraints on production-generated pollution emissions. The model demonstrates that reducing credit constraints increases the scale of production (scale effect) and increases the number of firms taking up production (market-size effect), while it also reduces emissions per unit of output (technique effect) and increases the share of firms investing in the technology upgrade (upgrading-composition effect). Because the former and latter effects are plausibly confounding in nature, the net effect of credit constraints on pollution emissions is an empirical question. This paper demonstrates, using variation in the timing of credit market reforms, that reducing credit constraints significantly improves air pollution. The results are robust using various approaches, including difference in differences (DID) with a rich set of controls, and an alternative DID approach, wherein the time series data are collapsed around credit reforms into a pre- and post-period.

We present self-consistent dynamical models for dust-driven winds of carbon-rich AGB stars. The models are based on the coupled system of frequency-dependent radiation hydrodynamics and time-dependent dust formation. We investigate in detail how the wind properties of the models are influenced by the micro-physical properties of the dust grains that are required by the description of grain formation. The choice of dust parameters is significant for the derived outflow velocities, the degrees of condensation and the resulting mass-loss rates of the models. In the transition region between models with and without mass-loss the choice of micro-physical parameters turns out to be very significant for whether a particular set of stellar parameters will give rise to a dust-driven mass-loss or not. We also calculate near-infrared colors to test how the dust parameters influence the observable properties of the models, however, at this point we do not attempt to fit particular stars.

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Certain dust particles in space are expected to appear as clusters of individual grains. The morphology of these clusters could be fractal or compact. In this paper we study the extinction by compact and fractal polycrystalline graphitic clusters consisting of touching identical spheres, based on the dielectric function of graphite from Draine & Lee ([CITE]). We compare three general methods for computing the extinction of the clusters in the wavelength range $0.1{-}100~\mu$m, namely, a rigorous solution (Gérardy & Ausloos [CITE]) and two different discrete-dipole approximation methods – MarCODES (Markel [CITE]) and DDSCAT (Draine & Flatau [CITE]). We consider clusters of $N=$4, 7, 8, 27, 32, 49, 108 and 343 particles of radii either 10 nm or 50 nm, arranged in three different geometries: open fractal (dimension $D = 1.77$), simple cubic and face-centred cubic. The rigorous solution shows that the extinction of the fractal clusters, with $N \le 50$and particle radii 10 nm, displays a peak within 2% of the location of the observed interstellar extinction peak at ~4.6 μm-1; the smaller the cluster, the closer its peak gets to this value. By contrast, the peak in the extinction of the more compact clusters lie more than 4% from 4.6 μm-1. At short wavelengths ($0.1{-}0.5$μm), all the methods show that fractal clusters have markedly different extinction from those of non-fractal clusters. At wavelengths >5 μm, the rigorous solution indicates that the extinction from fractal and compact clusters are of the same order of magnitude. It was only possible to compute fully converged results of the rigorous solution for the smaller clusters, due to computational limitations, however, we find that both discrete-dipole approximation methods overestimate the computed extinction of the smaller fractal clusters.

Parasitic nematodes are major human and agricultural pests, and benzimidazoles are amongst the most important broad-spectrum anthelmintic drug class used for their control. Benzimidazole resistance is now widespread in many species of parasitic nematodes in livestock globally and an emerging concern for the sustainable control of human soil-transmitted helminths. β-tubulin is the major benzimidazole target, although other genes may influence resistance. Among the 6 Caenorhabditis elegansβ-tubulin genes, loss of ben-1causes resistance without other apparent defects. Here, we explored the genetics of C. elegansβ-tubulin genes in relation to the response to the benzimidazole derivative albendazole. The most highly expressed β-tubulin isotypes, encoded by tbb-1and tbb-2, were known to be redundant with each other for viability, and their products are predicted not to bind benzimidazoles. We found that tbb-2mutants, and to a lesser extent tbb-1mutants, were hypersensitive to albendazole. The double mutant tbb-2 ben-1is uncoordinated and short, resembling the wild type exposed to albendazole, but the tbb-1 ben-1double mutant did not show the same phenotypes. These results suggest that tbb-2is a modifier of albendazole sensitivity. To better understand how BEN-1 mutates to cause benzimidazole resistance, we isolated mutants resistant to albendazole and found that 15 of 16 mutations occurred in the ben-1coding region. Mutations ranged from likely nulls to hypomorphs, and several corresponded to residues that cause resistance in other organisms. Null alleles of ben-1are albendazole-resistant and BEN-1 shows high sequence identity with tubulins from other organisms, suggesting that many amino acid changes could cause resistance. However, our results suggest that missense mutations conferring resistance are not evenly distributed across all possible conserved sites. Independent of their roles in benzimidazole resistance, tbb-1and tbb-2may have specialized functions as null mutants of tbb-1or tbb-2were cold or heat sensitive, respectively.

The European cross-border Project MARINEFFexplores the use of eco-friendly concrete materials in the construction of marine structures (oyster bed modules, dykes, boat moorings and rockpools). The structures and materials are designed to protect and improve the local biodiversity of the marine environment of the Channel / La Manche. This paper focuses on the mineralogical and microtextural characterization of the concrete materials. The aim is to introduce how advanced analytical methods have been employed to gain an understanding of the evolution of the materials, in particular their response to immersion into the sea. Our methods include the traditional techniques for examining concrete materials (optical microscopy, scanning electron microscopy, X-ray diffraction), but also introduces the benefits of mineralogical methods that go beyond the current “state-of-the-art” (automated scanning electron microscopy by QEMSCAN®, electron-probe microanalysis). Our results offer detailed insight into the controls on the compositional and structural evolution of the materials.

Background:The underlying neuro-protective mechanisms of antenatal magnesium sulfate (MgSO4) in infants born preterm remain poorly understood. Early neonatal brain injury may be preceded by low cerebral blood flow (CBF) and elevated cerebral fractional tissue oxygen extraction (cFTOE). This study investigated the effect of antenatal MgSO4on cerebral oxygen delivery, consumption, and cFTOE in preterm infants.Methods:CBF and tissue oxygenation index were measured, and oxygen delivery, consumption, and cFTOE calculated within 24?h of birth and at 48 and 72?h of life in 36 infants = 30?wk gestation exposed to MgSO4and 29 unexposed infants.Results:Total internal carotid blood flow and cerebral oxygen delivery did not differ between the groups at the three study time-points. Cerebral oxygen consumption and cFTOE were lower in infants exposed to antenatal MgSO4(P = 0.012) compared to unexposed infants within 24?h of delivery. This difference was not evident by 48?h of age. Fewer infants in the MgSO4group developed P/IVH by 72?h of age (P = 0.03).Conclusion:Infants exposed to MgSO4had similar systemic and cerebral hemodynamics but lower cFTOE compared to nonexposed. These findings suggest reduced cerebral metabolism maybe a component of the neuro-protective actions of antenatal MgSO4.

Orthopedic trauma remains one of the most survivable battlefield injuries seen in modern conflicts. Translating research into practice is a critical bridge that permits surgeons to further optimize medical outcomes. Orthopedic surgeons serving in the military may treat little to no trauma in their stateside practice. In conflict zones, however, the majority of their patients will have traumatic injuries. Determining risk factors for nonevidence-based practice can help identify provider knowledge gaps, which can then be targeted before deployment. Surveys were developed which sought to identify factors contributing to continued medical education and practice, as well as scenario-based questions on military-relevant orthopedic trauma. Analysis of 188 survey respondents revealed that providers with military service and less than 10 years of practice are optimally bridging research into military-relevant orthopedic trauma practice.