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Gamma-ray spectroscopy is an effective technique for radioactive material characterization, routine inventory verification, nuclear safeguards, health physics, and source search scenarios. Gamma-ray spectrometers typically cannot be operated in the immediate vicinity of nuclear reactors due to their high flux fields and their resulting inability to resolve individual pulses. Low-power reactor facilities offer the possibility to study reactor gamma-ray fields, a domain of experiments hitherto poorly explored. In this work, we present gamma-ray spectroscopy experiments performed with various detectors in two reactors: The EPFL zero-power research reactor CROCUS, and the neutron beam facility at the Ohio State University Research Reactor (OSURR). We employed inorganic scintillators (CeBr3), organic scintillators (trans-stilbene and organic glass), and high-purity germanium semiconductors (HPGe) to cover a range of typical—and new—instruments used in gamma-ray spectroscopy. The aim of this study is to provide a guideline for reactor users regarding detector performance, observed responses, and therefore available information in the reactor photon fields up to 2 MeV. The results indicate several future prospects, such as the online (at criticality) monitoring of fission products (like Xe, I, and La), dual-particle sensitive experiments, and code validation opportunities. [ABSTRACT FROM AUTHOR]

Several theories of belief processing assume that processing another's false belief requires overcoming an egocentric bias toward one's current knowledge. The current evidence in support of this claim, however, is limited. In order to investigate the presence of egocentric bias in adult belief processing, computer mouse tracking was used across three experiments to measure attraction toward response options reflecting one's current knowledge while reporting a false belief. Participants viewed scenarios in which an agent either had a true belief or a false belief about the location of a set of keys. Participants used a mouse to answer reality questions "where are the keys currently hidden?" and belief questions "where does she think the keys are?" Mouse-tracking measures indexing attraction toward response options during decision making were measured, along with time taken to make a response and accuracy. Experiment 1 found no evidence, in any measures, that participants showed a bias toward their own knowledge when reporting another's false belief. Experiment 2 investigated whether differences in event timings between true belief and false belief scenarios in Experiment 1 masked an egocentric bias. Experiment 3 investigated whether the lack of egocentric bias could be explained by participants prioritizing encoding the other's beliefs. Neither follow-up experiment found evidence supporting the presence of an egocentric bias. Overall, contrary to many theories of belief processing, our results suggest that adults are readily able to process other people's beliefs without having to overcome a default bias toward their own knowledge. [ABSTRACT FROM AUTHOR]

Harmful algal blooms (HABs) are increasing globally, causing economic, human health, and ecosystem harm. In spite of the frequent occurrence of HABs, the mechanisms responsible for their exceptionally high biomass remain imperfectly understood. A 50-y- old hypothesis posits that some dense blooms derive from dinoflagellate motility: organisms swim upward during the day to photosynthesize and downward at night to access deep nutrients. This allows dinoflagellates to outgrow their nonmotile competitors. We tested this hypothesis with in situ data from an autonomous, ocean-wave- powered vertical profiling system. We showed that the dinoflagellate Lingulodinium polyedra’s vertical migration led to depletion of deep nitrate during a 2020 red tide HAB event. Downward migration began at dusk, with the maximum migration depth determined by local nitrate concentrations. Losses of nitrate at depth were balanced by proportional increases in phytoplankton chlorophyll concentrations and suspended particle load, conclusively linking vertical migration to the access and assimilation of deep nitrate in the ocean environment. Vertical migration during the red tide created anomalous biogeochemical conditions compared to 70 y of climatological data, demonstrating the capacity of these events to temporarily reshape the coastal ocean’s ecosystem and biogeochemistry. Advances in the understanding of the physiological, behavioral, and metabolic dynamics of HAB-forming organisms from cutting-edge observational techniques will improve our ability to forecast HABs and mitigate their consequences in the future. [ABSTRACT FROM AUTHOR]

Network effects are the added value derived solely from the popularity of a product in an economic market. Using agent-based models inspired by statistical physics, we propose a minimal theory of a competitive market for (nearly) indistinguishable goods with demand-side network effects, sold by statistically identical sellers. With weak network effects, the model reproduces conventional microeconomics: there is a statistical steady state of (nearly) perfect competition. Increasing network effects, we find a phase transition to a robust nonequilibrium phase driven by the spontaneous formation and collapse of fads in the market. When sellers update prices sufficiently quickly, an emergent monopolist can capture the market and undercut competition, leading to a symmetry- and ergodicity-breaking transition. The nonequilibrium phase simultaneously exhibits three empirically established phenomena not contained in the standard theory of competitive markets: spontaneous price fluctuations, persistent seller profits, and broad distributions of firm market shares. [ABSTRACT FROM AUTHOR]

Space- and time-continuous seafloor temperature observations captured the three-dimensional structure of shoaling nonlinear internal waves (NLIWs) off of La Jolla, California. NLIWs were tracked for hundreds of meters in the cross- and along-shelf directions using a fiber optic distributed temperature sensing (DTS) seafloor array, complemented by an ocean-wave-powered vertical profiling mooring. Trains of propagating cold-water pulses were observed on the DTS array inshore of the location of polarity transition predicted by weakly nonlinear internal wave theory. The subsequent evolution of the temperature signatures during shoaling was consistent with that of strongly nonlinear internal waves with a large Froude number, highlighting their potential to impact property exchange. Unexpectedly, individual NLIWs were trailed by a coherent, small-scale pattern of seabed temperature variability as they moved across the mid- and inner shelf. A kinematic model was used to demonstrate that the observed patterns were consistent with a transverse instability with an along-crest wavelength of ∼10 m—a distance comparable to the cross-crest width of the wave core—and with an inferred amplitude of several meters. The signature of this instability is consistent with the span-wise vortical circulations generated in three-dimensional direct numerical simulations of shoaling and breaking nonlinear internal waves. The coupling between the small-scale transverse wave wake and turbulent wave core may have an important impact on mass, momentum, and tracer redistribution in the coastal ocean. Significance Statement: Internal waves permeate the ocean and atmosphere. Their transport of energy and momentum plays a central role in the ocean as a physical system and mediates critical biogeochemical property exchange. In the coastal ocean, internal waves fuel the local ecosystem by redistributing nutrients and shape the local geomorphology by resuspending and transporting sediment. Despite these important impacts, a detailed understanding of nonlinear internal wave evolution in shallow water remains an elusive goal, limited by the difficulty of observing the process in action. Here we describe a transformative observational approach to track internal waves through shoaling to dissipation, combining fiber optic distributed temperature sensing and ocean-wave-powered vertical profiling to track individual waves continuously in the cross- and along-shelf direction. The waves arise from the locally energetic internal tide and undergo rapid nonlinear transformation in the shallow waters of the inner shelf. Our measurements provide the first observational evidence that after evolving into highly nonlinear waves of elevation, the waves develop a trailing, wake-like, three-dimensional instability. This instability resembles the vortical coherent structures generated in high resolution numerical simulations of internal wave shoaling, previous observations of related phenomena in the atmosphere, and in breaking surface gravity waves. The observed transverse structure has an along-crest wavelength of only ∼10 m, making it nearly invisible to traditional ocean sampling techniques. The generation of coherent vortical structures during internal wave shoaling may have a profound influence on the exchange of energy, nutrients, and sediments in coastal oceans and lakes globally. [ABSTRACT FROM AUTHOR]

The ability to forecast the biological productivity of the coastal ocean relies on the quantification of the physical processes that deliver nutrients to the euphotic zone. Here we explore these pathways using observations of the coupled biological and physical variability of waters offshore of the east coast of Tasmania in the summertime. The observations include an array of moored autonomous profilers deployed over an 18‐d period—providing continuous, full‐depth measurements of turbulent microstructure, temperature, velocity, and chlorophyll a (Chl a) fluorescence, complemented by shipboard nutrient measurements. Local upwelling was driven by the encroaching East Australian Current (EAC) extension onto the shelf and to a lesser extent the local winds. The interaction of the local winds and the encroaching boundary current was reflected in the shelf nutrient budget and led to a rapid increase in subsurface Chl a. Diffusive vertical fluxes had minimal impact on subsurface Chl a in the mid‐shelf and outer‐shelf. Upwelling‐favorable winds were too weak to drive significant vertical mixing, and mixing associated with the current‐driven Ekman transport was too deep compared to the euphotic zone depth. The observed subsurface Chl a did not reflect the satellite estimates of productivity. Since the EAC extension transports warm, low‐nutrient surface waters from the subtropics, satellite chlorophyll measurements decreased during the same period the depth‐averaged Chl a increased. This seeming paradox illustrated how long duration, full water column sampling can elucidate the coupled biological and physical processes that aid our ongoing effort to forecast the biological state of the coastal ocean. [ABSTRACT FROM AUTHOR]

We develop a hydrodynamic effective field theory on the Schwinger-Keldysh contour for fluids with charge, energy, and momentum conservation, but only discrete rotational symmetry. The consequences of anisotropy on thermodynamics and first-order dissipative hydrodynamics are detailed in some simple examples in two spatial dimensions, but our construction extends to any spatial dimension and any rotation group (discrete or continuous). We find many possible terms in the equations of motion which are compatible with the existence of an entropy current, but not with the ability to couple the fluid to background gauge fields and vielbein. [ABSTRACT FROM AUTHOR]

The Wirewalker (WW) ocean-wave-powered vertical profiling system allows the collection of high-resolution oceanographic data due to its rapid profiling, hydrodynamically quiet operation, and long endurance. We have assessed the potential for measuring fine-scale ocean velocities from the Wirewalker platform using commercially available acoustic velocimeters. Although the vertical profiling speed is relatively steady, platform motion affects the velocity measurements and requires correction. We present an algorithm to correct our velocity estimates using platform motion calculated from the inertial sensors—accelerometer, gyroscope, and magnetometer—on a Nortek Signature1000 acoustic Doppler current profiler (ADCP). This correction, carried out ping by ping, was effective in removing the vehicle motion from the measured velocities. The motion-corrected velocities contain contributions from surface wave orbital velocities, especially near the surface, and the background currents. To proceed, we use an averaging approach that leverages both the vertical platform profiling of the system and the ∼15–20 m vertical profiling range resolution of the down-looking ADCP to separate the surface wave orbital velocities and the background flow. The former can provide information on the wave conditions. From the latter, we are able to estimate fine-scale velocity and shear with spectral wavenumber rolloff at vertical scales around 3 m, a vertical resolution several times finer than that possible from modern shipboard or fixed ADCPs with similar profiling range, and similar to recent glider measurements. When combined with a continuous time series of buoy drift calculated from the onboard GPS, a highly resolved total velocity field is obtained, with a unique combination of space and time resolution. [ABSTRACT FROM AUTHOR]

Let A and B be local operators in Hamiltonian quantum systems with N degrees of freedom and finite-dimensional Hilbert space. We prove that the commutator norm ‖ [ A (t) , B ] ‖ is upper bounded by a topological combinatorial problem: counting irreducible weighted paths between two points on the Hamiltonian's factor graph. Our bounds sharpen existing Lieb–Robinson bounds by removing extraneous growth. In quantum systems drawn from zero-mean random ensembles with few-body interactions, we prove stronger bounds on the ensemble-averaged out-of-time-ordered correlator E ‖ [ A (t) , B ] ‖ F 2 . In such quantum systems on Erdös–Rényi factor graphs, we prove that the scrambling time t s , at which ‖ [ A (t) , B ] ‖ F = Θ (1) , is almost surely t s = Ω (log N) ; we further prove t s = Ω (log N) to high order in perturbation theory in 1/N. We constrain infinite temperature quantum chaos in the q-local Sachdev-Ye-Kitaev model at any order in 1/N; at leading order, our upper bound on the Lyapunov exponent is within a factor of 2 of the known result at any q > 2 . We also speculate on the implications of our theorems for conjectured holographic descriptions of quantum gravity. [ABSTRACT FROM AUTHOR]

The article focuses on neuritin has unmasked as a checkpoint for the pathogenesis of allergy and autoimmunity. Topics include the follicular regulatory T cells (Tfr) in the germinal centre suppress the development of B-cell-driven autoimmunity and IgE-mediated allergic sensitisation via their secretion of the neuropeptide neuritin, and the unmasks a lack of neuritin as a previously unrecognised critical contributor to the development of allergic and autoimmune disease.

Cross-shore velocities in the coastal ocean typically vary with depth. The direction and magnitude of transport experienced by meroplanktonic larvae will therefore be influenced by their vertical position. To quantify how swimming behavior and vertical position in internal waves influence larval cross-shore transport in the shallow (~ 20 m), stratified coastal waters off Southern California, we deployed swarms of novel, subsurface larval mimics, the Mini-Autonomous Underwater Explorers (M-AUEs). The M-AUEs were programmed to maintain a specified depth, and were deployed near a mooring. Transport of the M-AUEs was predominantly onshore, with average velocities up to 14 cm s-1. To put the M-AUE deployments into a broader context, we simulated > 500 individual high-frequency internal waves observed at the mooring over a 14-d deployment; in each internal wave, we released both depth-keeping and passive virtual larvae every meter in the vertical. After the waves' passage, depth-keeping virtual larvae were usually found closer to shore than passive larvae released at the same depth. Near the top of the water column (3-5-m depth), ~ 20% of internal waves enhanced onshore transport of depth-keeping virtual larvae by ≥ 50 m, whereas only 1% of waves gave similar enhancements to passive larvae. Our observations and simulations showed that depth-keeping behavior in high-frequency internal waves resulted in enhanced onshore transport at the top of the water column, and reduced offshore dispersal at the bottom, compared to being passive. Thus, even weak depth-keeping may allow larvae to reach nearshore adult habitats more reliably than drifting passively. [ABSTRACT FROM AUTHOR]

Large-scale electrical and thermal currents in ordinary metals are well approximated by effective medium theory: global transport properties are governed by the solution to homogenized coupled diffusion equations. In some metals, including the Dirac fluid of nearly charge neutral graphene, microscopic transport is not governed by diffusion, but by a more complicated set of linearized hydrodynamic equations, which form a system of degenerate elliptic equations coupled with the Stokes equation for fluid velocity. In sufficiently inhomogeneous media, these hydrodynamic equations reduce to homogenized diffusion equations. We recast the hydrodynamic transport equations as the infimum of a functional over conserved currents and present a functional framework to model and compute the homogenized diffusion tensor relating electrical and thermal currents to charge and temperature gradients. We generalize to this system to the well-known results in homogenization theory: Tartar's proof of local convergence to the homogenized theory in periodic and highly oscillatory media and sub-additivity of the above functional in random media with highly oscillatory, stationary, and ergodic coefficients. [ABSTRACT FROM AUTHOR]

We initiate a study of finite temperature transport in gapless and strongly coupled quantum theories with charge and dipole conservation using gauge-gravity duality. In a model with non-dynamical gravity, the bulk fields of our model include a suitable mixed-rank tensor which encodes the boundary multipole symmetry. We describe how such a theory can arise at low energies in a theory with a covariant bulk action. Studying response functions at zero density, we find that charge relaxes via a fourth-order subdiffusion equation, consistent with a recently-developed field-theoretic framework. [ABSTRACT FROM AUTHOR]

We study operator growth in a model of N(N − 1)/2 interacting Majorana fermions that live on the edges of a complete graph of N vertices. Terms in the Hamiltonian are proportional to the product of q fermions that live on the edges of cycles of length q. This model is a cartoon "matrix model": the interaction graph mimics that of a single-trace matrix model, which can be holographically dual to quantum gravity. We prove (non-perturbatively in 1/N and without averaging over any ensemble) that the scrambling time of this model is at least of order log N, consistent with the fast scrambling conjecture. We comment on apparent similarities and differences between operator growth in our "matrix model" and in the melonic models. [ABSTRACT FROM AUTHOR]

We prove non-perturbative bounds on the time evolution of the probability distribution of operator size in the q-local Sachdev–Ye–Kitaev model with N fermions for any even integer q > 2 and any positive even integer N > 2q. If the couplings in the Hamiltonian are independent and identically distributed Rademacher random variables, the infinite temperature many-body Lyapunov exponent is almost surely finite as N → ∞. In the limit q → ∞, N → ∞, and q6+δ/N → 0, the shape of the size distribution of a growing fermion, obtained by leading order perturbation calculations in 1/N and 1/q, is similar to a distribution that locally saturates our constraints. Our proof is not based on Feynman diagram resummation; instead, we note that the operator size distribution obeys a continuous time quantum walk with bounded transition rates to which we apply concentration bounds from classical probability theory. [ABSTRACT FROM AUTHOR]

The lung achieves an efficient gas exchange between a complex non‐sterile atmosphere and the body via a delicate and extensive epithelial surface, with high efficiency because of elastic deformation allowing for an increase and decrease in volume during the process of breathing and because of an extensive vasculature which aids rapid gas diffusion. The lungs' large surface area exposes the organ to a continual risk of damage from pathogens, toxins or irritants; however, lung damage can be rapidly healed via regenerative processes that restore its structure and function. In response to sustained and extensive damage, the lung is healed via a non‐regenerative process resulting in scar tissue which locally stiffens its structure, which over time leads to a serious loss of lung function and to increasing morbidities. This review discusses what is known about the factors which influence whether a lung is healed by regeneration or repair and what potential new therapeutic approaches may positively influence lung healing. [ABSTRACT FROM AUTHOR]

Coastal physical processes are essential for the cross‐shore transport of meroplanktonic larvae to their benthic adult habitats. To investigate these processes, we released a swarm of novel, trackable, subsurface vehicles, the Mini‐Autonomous Underwater Explorers (M‐AUEs), which we programmed to mimic larval depth‐keeping behavior. The M‐AUE swarm measured a sudden net onshore transport of 30–70 m over 15–20 min, which we investigated in detail. Here, we describe a novel transport mechanism of depth‐keeping plankton revealed by these observations. In situ measurements and models showed that, as a weakly nonlinear internal wave propagated through the swarm, it deformed surface‐intensified, along‐isopycnal background velocities downward, accelerating depth‐keeping organisms onshore. These higher velocities increased both the depth‐keepers' residence time in the wave and total cross‐shore displacement, leading to wave‐induced transports twice those of fully Lagrangian organisms and four times those associated with the unperturbed background currents. Our analyses also show that integrating velocity time series from virtual larvae or mimics moving with the flow yields both larger and more accurate transport estimates than integrating velocity time series obtained at a point (Eulerian). The increased cross‐shore transport of organisms capable of vertical swimming in this wave/background‐current system is mathematically analogous to the increase in onshore transport associated with horizontal swimming in highly nonlinear internal waves. However, the mechanism described here requires much weaker swimming speeds (mm s−1 vs. cm s−1) to achieve significant onshore transports, and meroplanktonic larvae only need to orient themselves vertically, not horizontally. [ABSTRACT FROM AUTHOR]

We revisit the theory of strongly correlated quantum matter perturbed by Harris-marginal random-field disorder, using the simplest holographic model. We argue that for weak disorder, the ground state of the theory is not Lifshitz invariant with a non-trivial disorder-dependent dynamical exponent, as previously found. Instead, below a non-perturbatively small energy scale, we predict infrared physics becomes independent of the disorder strength. [ABSTRACT FROM AUTHOR]

Level crossing rails are high risk areas due to the combination of the limited effectiveness of current inspection methods and high corrosion rates which often exist. This paper discusses the current UK standard practices for the periodic inspection of level crossing rails using visual (VT) and conventional ultrasonic (UT) methods. The limitations of these methods are discussed and how these limitations affect the overall maintenance program for level crossings. A new inspection method, guided wave testing (GWT) is then described with particular emphasis on its advantages for inspecting level crossings. GWT was first commercially used for the inspection of pipes from around 1999 (Alleyne et al., 2001) [1] and has now gained very widespread usage. Finally, a review is given of the current Network Rail trial of GWT on level crossings using the G-Scan system, with representative results which demonstrate the effectiveness of GWT for this application. [ABSTRACT FROM AUTHOR]

1. Pollination by insects is a key ecosystem service and important to wider ecosystem function. Most species-level pollination networks studied have a generalised structure, with plants having several potential pollinators, and pollinators in turn visiting a number of different plant species. This is in apparent contrast to a plant's need for efficient conspecific pollen transfer. 2. The aim of this study was to investigate the structure of pollen transport networks at three levels of biological hierarchy: community, species and individual. We did this using hoverflies in the genus Eristalis, a key group of non-Hymenopteran pollinators. 3. We constructed pollen transport networks using DNA metabarcoding to identify pollen. We captured hoverflies in conservation grasslands in west Wales, UK, removed external pollen loads, sequenced the pollen DNA on the Illumina MiSeq platform using the standard plant barcode rbcL, and matched sequences using a pre-existing plant DNA barcode reference library. 4. We found that Eristalis hoverflies transport pollen from 65 plant taxa, more than previously appreciated. Networks were generalised at the site and species level, suggesting some degree of functional redundancy, and were more generalised in late summer compared to early summer. In contrast, pollen transport at the individual level showed some degree of specialisation. Hoverflies defined as "singleplant visitors" varied from 40% of those captured in early summer to 24% in late summer. Individual hoverflies became more generalised in late summer, possibly in response to an increase in floral resources. Rubus fruticosus agg. and Succisa pratensis were key plant species for hoverflies at our sites 5. Our results contribute to resolving the apparent paradox of how generalised pollinator networks can provide efficient pollination to plant species. Generalised hoverfly pollen transport networks may result from a varied range of short-term specialised feeding bouts by individual insects. The generalisation and functional redundancy of Eristalis pollen transport networks may increase the stability of the pollination service they deliver. [ABSTRACT FROM AUTHOR]

Major advances in therapeutic proteins, including antibody-drug conjugates (ADCs), have created revolutionary drug delivery systems in cancer over the past decade. While these immunoconjugate agents provide several advantages compared to their small-molecule counterparts, their clinical use is still in its infancy. The considerations in their development and clinical use are complex, and consist of multiple components and variables that can affect the pharmacologic characteristics. It is critical to understand the mechanisms employed by ADCs in navigating biological barriers and how these factors affect their biodistribution, delivery to tumors, efficacy, and toxicity. Thus, future studies are warranted to better understand the complex pharmacology and interaction between ADC carriers and biological systems, such as the mononuclear phagocyte system (MPS) and tumor microenvironment. This review provides an overview of factors that affect the pharmacologic profiles of ADC therapies that are currently in clinical use and development. [ABSTRACT FROM AUTHOR]

At zero temperature, the charge current operator appears to be conserved, within linear response, in certain holographic probe brane models of strange metals. At small but finite temperature, we analytically show that the weak non-conservation of this current leads to both a collective “zero sound” mode and a Drude peak in the electrical conductivity. This simultaneously resolves two outstanding puzzles about probe brane theories. The nonlinear dynamics of the current operator itself appears qualitatively different. [ABSTRACT FROM AUTHOR]

We obtain a rigorous upper bound on the resistivity ρ of an electron fluid whose electronic mean free path is short compared with the scale of spatial inhomogeneities. When such a hydrodynamic electron fluid supports a nonthermal diffusion process--such as an imbalance mode between different bands--we show that the resistivity bound becomes ρ ≲ A Γ. The coefficient A is independent of temperature and inhomogeneity lengthscale, and Γ is a microscopic momentum-preserving scattering rate. In this way, we obtain a unified mechanism--without umklapp--for ρ ~ T² in a Fermi liquid and the crossover to ρ ~ T in quantum critical regimes. This behavior is widely observed in transition metal oxides, organic metals, pnictides, and heavy fermion compounds and has presented a long-standing challenge to transport theory. Our hydrodynamic bound allows phonon contributions to diffusion constants, including thermal diffusion, to directly affect the electrical resistivity. [ABSTRACT FROM AUTHOR]

Pollination is a key ecosystem service, and appropriate management, particularly in agricultural systems, is essential to maintain a diversity of pollinator guilds. However, management recommendations frequently focus on maintaining plant communities, with the assumption that associated invertebrate populations will be sustained. We tested whether plant community, flower resources, and soil moisture would influence hoverfly (Syrphidae) abundance and species richness in floristically-rich seminatural and floristically impoverished agricultural grassland communities in Wales (U.K.) and compared these to two Hymenoptera genera, Bombus, and Lasioglossum. Interactions between environmental variables were tested using generalized linear modeling, and hoverfly community composition examined using canonical correspondence analysis. There was no difference in hoverfly abundance, species richness, or bee abundance, between grassland types. There was a positive association between hoverfly abundance, species richness, and flower abundance in unimproved grasslands. However, this was not evident in agriculturally improved grassland, possibly reflecting intrinsically low flower resource in these habitats, or the presence of plant species with low or relatively inaccessible nectar resources. There was no association between soil moisture content and hoverfly abundance or species richness. Hoverfly community composition was influenced by agricultural improvement and the amount of flower resource. Hoverfly species with semiaquatic larvae were associated with both seminatural and agricultural wet grasslands, possibly because of localized larval habitat. Despite the absence of differences in hoverfly abundance and species richness, distinct hoverfly communities are associated with marshy grasslands, agriculturally improved marshy grasslands, and unimproved dry grasslands, but not with improved dry grasslands. Grassland plant community cannot be used as a proxy for pollinator community. Management of grasslands should aim to maximize the pollinator feeding resource, as well as maintain plant communities. Retaining waterlogged ground may enhance the number of hoverflies with semiaquatic larvae. [ABSTRACT FROM AUTHOR]

This study investigates three-dimensional semidiurnal internal tide (IT) energetics in the vicinity of La Jolla Canyon, a steep shelf submarine canyon off the Southern California coast, with the Stanford Unstructured Nonhydrostatic Terrain-Following Adaptive Navier–Stokes Simulator (SUNTANS) numerical simulator. Numerical simulations show vertical structure and temporal phasing consistent with detailed field observations. ITs induce large (approximately 34 m from peak to peak) isotherm displacements and net onshore IT energy flux up to 200 W m−1. Although the net IT energy flux is onshore, the steep supercritical slope around the canyon results in strong reflection. The model provides the full life span of internal tides around the canyon, including internal tide generation, propagation, and dissipation. ITs propagate into the canyon from the south and are reflected back toward offshore from the canyon's north side. In the inner part of the canyon, elevated mixing occurs in the middle layer due to an interaction between incident mode-1 ITs and reflected higher-mode ITs. The magnitude of IT flux, generation, and dissipation on the south side of the canyon are higher than those on the north side. An interference pattern in horizontal kinetic energy and available potential energy with a scale of approximately 20–50 km arises due to low-mode wave reflections. Our results provide new insight into IT dynamics associated with a small-scale canyon topography. Significance Statement: Internal waves play an important role in ocean circulations and ecosystems. In particular, internal waves with frequencies of tides, known as internal tides, strongly enhance energy, heat, and mass transport in coastal oceans. This study presents internal tide dynamics in La Jolla Canyon, California, using a high-resolution numerical model. Model results show energy convergence in the canyon leading to internal tide energy dissipation and mixing. Some parts of internal tide energy reflect back offshore resulting in standing internal waves off California. This study provides new insights into internal tide dynamics and energy budgets in submarine canyons. [ABSTRACT FROM AUTHOR]

The article reports developments in the emerald industry in Colombia as of September 2017. Also cited are how indigenous people mined emeralds before the Spanish colonization in 1499, the privatized mining pioneered by Tecminas and Esmeracol SA, and the Green War among the drug cartels in the country that entered the emerald mining industry.

We study the spread of Rényi entropy between two halves of a Sachdev-Ye-Kitaev (SYK) chain of Majorana fermions, prepared in a thermofield double (TFD) state. The SYK chain model is a model of chaotic many-body systems, which describes a one-dimensional lattice of Majorana fermions, with spatially local random quartic interaction. We find that for integer Rényi index n > 1, the Rényi entanglement entropy saturates at a parametrically smaller value than expected. This implies that the TFD state of the SYK chain does not rapidly thermalize, despite being maximally chaotic: instead, it rapidly approaches a prethermal state. We compare our results to the signatures of thermalization observed in other quenches in the SYK model, and to intuition from nearly-AdS gravity. [ABSTRACT FROM AUTHOR]

Studies have shown that nanoparticles (NPs) are cleared through the mononuclear phagocyte system (MPS). Pharmacokinetic studies of Doxil, DaunoXome, micellar doxorubicin (SP1049C) and small molecule (SM) doxorubicin were performed in SCID mice, Sprague-Dawley rats, and beagle dogs. An ex vivo MPS profiling platform was used to evaluate the interaction between the same agents, as well as colloid-forming and non-colloid forming SM drugs. In all species, the systemic clearance was highest for SP1049C and lowest for Doxil. With the exception of dog blood, the MPS screening results of mouse and rat blood showed that the greatest reduction in phagocytosis occurred after the ex vivo addition of SM-doxorubicin > SP1049C > DaunoXome > Doxil. The MPS profiling platform in rats, but not dogs, could differentiate between colloid forming and non-colloid forming drugs. The results of the MPS profiling platform were generally consistent with in vivo clearance rates of NP and SM anticancer drugs in mice and rats. This study suggests the MPS profiling platform is an effective method to screen and differentiate the important characteristics of NPs and colloid-forming drugs that affect their in vivo clearance. Implications of these findings on preclinical prediction of human clearance are discussed. [ABSTRACT FROM AUTHOR]

The article talks about mining of Sapphire in Montana, United States that includes two major places like Missouri River gravel bars, Dry Cottonwood Creek, Yogo Gulch as the primary deposit and exploitation of alluvial sapphire deposit. It discusses about sapphires at Rock Creek known as Gem Mountain, gold miners discovering Montana sapphire crystals in the gravel bars in upper Missouri River, heat treatment done to enhance the quality and sold to gem dealers, jewelers and hobbyists.

We observed the fine-scale vertical variability of a wastewater plume discharged into shallow, stratified coastal waters with a set of wave-powered profiling moorings and bottom-mounted Acoustic Doppler Current Profilers. These in situ observations demonstrated that the effluent plume occupied a variable portion of the water column, but was typically at or above the pycnocline. The plume was characterized by small vertical scales away from the surface, while complicated patterns of vertical temperature and salinity compensation were found in the plume above the pycnocline. The particular design of the diffuser led to an effluent plume that was roughly split between depth-trapped and trapped at the surface. Estimates of dilution from temperature/salinity diagrams indicated that the plume dilution ranged between 60 and 120, and that the environmental mixing end-members ranged from waters well below the pycnocline to the waters at or near the surface. Far from the outfall, oceanographic variability at frequencies equal to and higher than the diurnal frequency dominated the vertical shear in local currents and thus the vertical and temporal distribution of the plume. Mixing driven by the high frequency non-linear internal waves and bore-like manifestations of the cross-shore baroclinic tide, as suggested by elevated inverse Richardson number within the leading and trailing edge of the bores, was likely the primary source of mixing between the plume and ambient waters far from the outfall. Complicated patterns in plume water characteristics demonstrated the complexity of the plume dilution even in a surfacing plume. The co-occurrence of elevated chlorophyll fluorescence and plume waters was evident in the later part of the diversion period, but the overall response of the phytoplankton to the effluent diversion was limited. Implications for outfall wastewater monitoring and diffuser design are briefly considered. [ABSTRACT FROM AUTHOR]

Eutrophication of coastal waters is an urgent and globally increasing problem. A significant source of nutrients to Southern California coastal waters is direct discharge of secondarily treated wastewater effluent from regional Publicly Owned Treatment Works. The planned diversion of treated wastewater from the Orange County Sanitation District's main (5-mile) pipe to a shallow 1-mile pipe off Huntington Beach, CA in autumn 2012 provided an unprecedented opportunity to monitor the response of the coastal phytoplankton community to a major anthropogenic loading event. Despite the continuous release of approximately 11.07 × 10 6 m 3 of effluent containing 1743 μM ammonium, there was virtually no detectable change in phytoplankton biomass, in striking contrast to the harmful algal bloom dominated community that quickly developed in response to a comparable diversion in Santa Monica Bay in 2006. Field and laboratory studies demonstrate that disinfection byproducts associated with enhanced dechlorination were present in the discharged water, and that these compounds had a strong inhibitory impact on phytoplankton photophysiology and growth, lasting 24 h for photosynthetic performance and at least 3 d for growth, assessed as change in chlorophyll. Thus, the perhaps fortuitous unintended consequence of enhanced chlorination was the production of inhibitory compounds that suppressed the potential phytoplankton response over a large swath of the continental shelf during the diversion. [ABSTRACT FROM AUTHOR]

In 2015, a field team from GIA visited the Indian city of Jaipur to capture the full scope of its gem and jewelry industry: colored stone cutting, wholesale trading, jewelry design, manufacturing, and retail. The authors documented the current state of the industry from a manufacturing as well as a business perspective. The results substantiated many of the team's prior assessments but also brought to light recent developments with far-reaching effects. The impact of vertical integration, consolidation, globalization, and jewelry television retail far exceeded expectations. Once known as a colored stone manufacturing center, Jaipur has rapidly climbed the value chain into jewelry manufacturing and retail by successfully incorporating experience and tradition with technology and innovation. [ABSTRACT FROM AUTHOR]

An at-sea experiment in deep water was conducted to explore the impact of small-scale sound-speed variability on mid-frequency (1 – 10 kHz) acoustic propagation. Short-range (1 – 5 km) acoustic transmissions were sent through the upper ocean (0 – 200 m) while oceanographic instruments simultaneously measured the ocean environment within 2 km of the single upper turning points of the acoustic transmissions. During these transmissions, acoustic receptions over a 7.875 m vertical line array show closely spaced, sometimes interfering arrivals. Ray and full-wave simulations of the transmissions using nearby sound-speed profiles are compared deterministically to the received acoustic signals. The sensitivity of the acoustic arrivals to the vertical scales of ocean sound speed is tested by comparing the observed and simulated arrival intensity where the sound-speed profile used by the simulation is smoothed to varying scales. Observations and modeling both suggest that vertical fine-scale structures (1 – 10 m) embedded in the sound-speed profile have strong second derivatives which allow for the formation of acoustic caustics as well as potentially interfering acoustic propagation multipaths. [ABSTRACT FROM AUTHOR]

We present a theory of thermoelectric transport in weakly disordered Weyl semimetals where the electron–electron scattering time is faster than the electron–impurity scattering time. Our hydrodynamic theory consists of relativistic fluids at each Weyl node, coupled together by perturbatively small intervalley scattering, and long-range Coulomb interactions. The conductivity matrix of our theory is Onsager reciprocal and positive semidefinite. In addition to the usual axial anomaly, we account for the effects of a distinct, axial–gravitational anomaly expected to be present in Weyl semimetals. Negative thermal magnetoresistance is a sharp, experimentally accessible signature of this axial–gravitational anomaly, even beyond the hydrodynamic limit. [ABSTRACT FROM AUTHOR]

The structure and variability of upper-ocean properties in the Bay of Bengal (BoB) modulate air-sea interactions, which profoundly influence the pattern and intensity of monsoonal precipitation across the Indian subcontinent. In turn, the bay receives a massive amount of freshwater through river input at its boundaries and from heavy local rainfall, leading to a salinity-stratified surface ocean and shallow mixed layers. Small-scale oceanographic processes that drive variability in near-surface BoB waters complicate the tight coupling between ocean and atmosphere implicit in this seasonal feedback. Unraveling these ocean dynamics and their impact on airsea interactions is critical to improving the forecasting of intraseasonal variability in the southwest monsoon. To that end, we deployed a wave-powered, rapidly profiling system capable of measuring the structure and variability of the upper 100 m of the BoB. The evolution of upper-ocean structure along the trajectory of the instrument's roughly two-week drift, along with direct estimates of vertical fluxes of salt and heat, permit assessment of the contributions of various phenomena to temporal and spatial variability in the surface mixed layer depth. Further, these observations suggest that the particular "barrier-layer" stratification found in the BoB may decrease the influence of the wind on mixing processes in the interior, thus isolating the upper ocean from the interior below, and tightening its coupling to the atmosphere above. [ABSTRACT FROM AUTHOR]

Background: In 2013, the American Society of Health-System Pharmacists (ASHP) endorsed a policy recommending the development of nationally standardized drug concentrations and dosing units. Although many hospitals have started standardizing their intravenous (IV) solutions, few have taken the practice beyond their institutions or local geographical areas. Objective: This project evaluates the current IV standardization practices for adult patients across hospitals in North Carolina and compares them with each other. In addition, this project proposed standards and evaluated them for their impact on reducing observed variability. Methods: In the fall of 2013, an e-mail request was sent to select hospital pharmacy leaders in North Carolina asking them to voluntarily submit a copy of their adult IV standard concentrations and dosing guidelines. From these lists, the data were summarized and compiled to evaluate trends and compare the various policies. Results: A total of 18 different hospitals and health systems responded. Survey results showed more than 255 concentrations for 84 unique drugs. Of these, 37 were high-risk medications, with 135 unique drug concentrations. From this list, a single proposed concentration was developed for each medication. If utilized, this standardization would result in a greater than 65% reduction in potential drug concentrations in use. A single dosing unit was also proposed for all medications reviewed, resulting in a greater than 21% reduction in variation. Conclusions: Standardization of IV drug concentrations and dosing units statewide could reduce the variability in IV therapies and promote safer and more consistent practices in medication administration. [ABSTRACT FROM AUTHOR]

Doxorubicin, a widely used anticancer agent, exhibits antitumor activity against a wide variety of malignancies. The drug exerts its cytotoxic effects by binding to and intercalating within the DNA of tumor and tissue cells. However, current assays are unable to accurately determine the concentration of the intracellular active form of doxorubicin. Thus, the development of a sample processing method and a high-performance liquid chromatography (HPLC) methodology was performed in order to quantify doxorubicin that is associated with DNA in tumors and tissues, which provided an intracellular cytotoxic measure of doxorubicin exposure after administration of small molecule and nanoparticle formulations of doxorubicin. The assay uses daunorubicin as an internal standard; liquid–liquid phase extraction to isolate drug associated with DNA; a Shimadzu HPLC with fluorescence detection equipped with a Phenomenex Luna C18 (2 μm, 2.0 × 100 mm) analytical column and a gradient mobile phase of 0.1% formic acid in water or acetonitrile for separation and quantification. The assay has a lower limit of detection (LLOQ) of 10 ng/mL and is shown to be linear up to 3000 ng/mL. The intra- and inter-day precision of the assay expressed as a coefficient of variation (CV%) ranged from 4.01 to 8.81%. Furthermore, the suitability of this assay for measuring doxorubicin associated with DNA in vivo was demonstrated by using it to quantify the doxorubicin concentration within tumor samples from SKOV3 and HEC1A mice obtained 72 h after administration of PEGylated liposomal doxorubicin (Doxil ® ; PLD) at 6 mg/kg IV x 1. This HPLC assay allows for sensitive intracellular quantification of doxorubicin and will be an important tool for future studies evaluating intracellular pharmacokinetics of doxorubicin and various nanoparticle formulations of doxorubicin. [ABSTRACT FROM AUTHOR]

This study reports the first surface water evaluation of the temporal and spatial variability of Au in an estuary, using recently developed modifications to the diffusive gradients in thin films (DGT) and grab sampling techniques. At the two study sites in the Swan River estuary that were more marine in character, the DGT-measured concentrations of Au (26.3 and 31.3 ng/L) were within the range of total concentrations measured on individual days (13.2–30.6 ng/L and 11.2–37.2 ng/L, respectively). In contrast, at an upstream site, Au concentrations measured by DGT were significantly lower than totals (3.9 ng/L for DGT, compared with 13.2–28.8 ng/L for grab sampling), likely due to either size exclusion of colloids (>70 nm) by DGT or formation of a dissolved, non-DGT-labile Au species (<0.45 μm). DGT-measured concentrations of other metals (Cu, Co, Cr, U, V, Mo and As) were also lower than total concentrations, although in contrast to DGT-measured Au, this phenomenon occurred at all sites. Furthermore, daily grab samples for Au, taken over the 10-day deployment (which included a rain event), showed that Au concentrations could spike substantially (from 15.1 ng/L to 37.2 ng/L) over intervals as short as one day. The combination of simultaneous deployment of different DGT devices and grab sampling represents a new development in efforts to understand the transport and fate of Au together with other elements in dynamic environments such as estuaries. [ABSTRACT FROM AUTHOR]

The article provides information on the opal industry of Australia. Topics discussed include opal formation on the Great Artesian Basin, the black opal and opalized fossils found in Lightning Ridge area in New South Wales, and the boulder opal found in Queensland fields. Also noted are the challenges facing the Australian opal industry such as drought.

The article offers information on a museum exhibition titled "Nature Art Science" in which artist Paula Crevoshay displayed her gems and precious stones.

We model strange metals as quantum liquids without quasiparticle excitations, but with slow momentum relaxation and with slow diffusive dynamics of a conserved charge and energy. General expressions are obtained for electrical, thermal, and thermoelectric transport in the presence of an applied magnetic field using the memory matrix formalism. In the appropriate limits, our expressions agree with previous hydrodynamic and holographic results. We discuss the relationship of such results to thermoelectric and Hall transport measurements in the strange-metal phase of the hole-doped cuprates. [ABSTRACT FROM AUTHOR]

We present a semi-analytic method for constructing holographic black holes that interpolate from anti-de Sitter space to hyperscaling-violating geometries. These are holographic duals of conformal field theories in the presence of an applied chemical potential, μ , at a non-zero temperature, T , and allow us to describe the crossover from ‘strange metal’ physics at T ≪ μ , to conformal physics at T ≫ μ . Our holographic technique adds an extra gauge field and exploits structure of the Einstein–Maxwell system to manifestly find 1-parameter families of solutions of the Einstein-matter system in terms of a small family of functions, obeying a nested set of differential equations. Using these interpolating geometries, we re-consider holographically some recent questions of interest about hyperscaling-violating field theories. Our focus is a more detailed holographic computation of the conductivity of strange metals, weakly perturbed by disorder coupled to scalar operators, including both the average conductivity as well as sample-to-sample fluctuations. Our findings are consistent with previous scaling arguments, though we point out logarithmic corrections in some special (holographic) cases. We also discuss the nature of superconducting instabilities in hyperscaling-violating geometries with appropriate choices of scalar couplings. [ABSTRACT FROM AUTHOR]

When the same gems and precious metals are used in jewelry, design is the element that ultimately distinguishes one piece from another. Real success is measured not only by the value of its materials but also by the character and quality of the design and craftsmanship. Once considered a weak point of China's gem and jewelry industry, design has seen tremendous progress over the last decade. Benefiting from the availability of more gem materials and the power of a rapidly growing consumer market, Chinese designers now have the freedom to develop their design concepts and craftsmanship skills. Designers from mainland China, Hong Kong, and Taiwan share the bond of cultural identity and have found ways to create jewelry that expresses the Chinese soul. [ABSTRACT FROM AUTHOR]

Background: Fifty-five percent of individuals with HLA-B*57:01 exposed to the antiretroviral drug abacavir develop a hypersensitivity reaction (HSR) that has been attributed to naïve T-cell responses to neo-antigen generated by the drug. Immunologically confirmed abacavir HSR can manifest clinically in less than 48 hours following first exposure suggesting that, at least in some cases, abacavir HSR is due to re-stimulation of a pre-existing memory T-cell population rather than priming of a high frequency naïve T-cell population. Methods: To determine whether a pre-existing abacavir reactive memory T-cell population contributes to early abacavir HSR symptoms, we studied the abacavir specific naïve or memory T-cell response using HLA-B*57:01 positive HSR patients or healthy controls using ELISpot assay, intra-cellular cytokine staining and tetramer labelling. Results: Abacavir reactive CD8+ T-cell responses were detected in vitro in one hundred percent of abacavir unexposed HLA-B*57:01 positive healthy donors. Abacavir-specific CD8+ T cells from such donors can be expanded from sorted memory, and sorted naïve, CD8+ T cells without need for autologous CD4+ T cells. Conclusions: We propose that these pre-existing abacavir-reactive memory CD8+ T-cell responses must have been primed by earlier exposure to another foreign antigen and that these T cells cross-react with an abacavir-HLA-B*57:01-endogenous peptide ligand complex, in keeping with the model of heterologous immunity proposed in transplant rejection. [ABSTRACT FROM AUTHOR]

We describe a simple model of heterogeneous, interacting agents making decisions between n ≥ 2 discrete choices. For a special class of interactions, our model is the mean field description of random field Potts-like models and is effectively solved by finding the extrema of the average energy E per agent. In these cases, by studying the propagation of decision changes via avalanches, we argue that macroscopic dynamics is well captured by a gradient flow along E. We focus on the permutation symmetric case, where all n choices are (on average) the same, and spontaneous symmetry breaking (SSB) arises purely from cooperative social interactions. As examples, we show that bimodal heterogeneity naturally provides a mechanism for the spontaneous formation of hierarchies between decisions and that SSB is a preferred instability to discontinuous phase transitions between two symmetric points. Beyond the mean field limit, exponentially many stable equilibria emerge when we place this model on a graph of finite mean degree. We conclude with speculation on decision making with persistent collective oscillations. Throughout the paper, we emphasize analogies between methods of solution to our model and common intuition from diverse areas of physics, including statistical physics and electromagnetism. [ABSTRACT FROM AUTHOR]

The ranslationally-ontrolled umor rotein (TCTP) is a highly conserved, ubiquitously expressed, abundant protein that is broadly distributed among eukaryotes. Its biological function spans numerous cellular processes ranging from regulation of the cell cycle and microtubule stabilization to cell growth, transformation, and death processes. In this work, we propose a new function for TCTP as a “buffer protein” controlling cellular homeostasis. We demonstrate that binding of hemin to TCTP is mediated by a conserved His-containing motif (His76His77) followed by dimerization, an event that involves ligand-mediated conformational changes and that is necessary to trigger TCTP's cytokine-like activity. Mutation in both His residues to Ala prevents hemin from binding and abrogates oligomerization, suggesting that the ligand site localizes at the interface of the oligomer. Unlike heme, binding of Ca2+ ligand to TCTP does not alter its monomeric state; although, Ca2+ is able to destabilize an existing TCTP dimer created by hemin addition. In agreement with TCTP's proposed buffer function, ligand binding occurs at high concentration, allowing the “buffer” condition to be dissociated from TCTP's role as a component of signal transduction mechanisms. [ABSTRACT FROM AUTHOR]

The mobility of groundwater and its reactivity with subsurface lithologies makes it an ideal medium for investigating both the mineralogy of the extensive volume of the rocks and soils that it comes into contact with, including the distribution of potential commodities, and the presence of contaminants. Groundwater grab sampling is potentially an effective tool for evaluating metal and metalloid concentrations but can suffer from poor replication and high detection limits. This study evaluates the diffusive gradients in thin films (DGT) technique to detect signatures of Au mineralization in groundwater, as well as associated pathfinder and potential contaminant elements (As and Sb). The DGT technique was modified for Au by evaluating a "gel-less" configuration, with diffusion onto an activated carbon binding layer being controlled by the 0.13 mm thick filter membrane (0.45 μm porosity) only, in order to increase sensitivity in quiescent solutions. Laboratory-based measurements indicated that the diffusive boundary layer (DBL) was ∼0.40 mm in thickness in quiescent solutions. The modified DGT samplers were then deployed alongside ferrihydrite DGT devices (fitted with 0.8 mm diffusive gels) to simultaneously measure Au, As and Sb in groundwaters surrounding a known arsenopyrite-hosted Au ore body. DGT-measured Au concentrations ranged from 2.0 ng/L to 38.5 ng/L, and were within a factor of 5 of grab sample concentrations. DGT-measured concentrations of As and Sb were above the detection limits, while grab sample concentrations of As and Sb were often close to or below detection. The DGT technique demonstrated methodological improvement over grab sampling of groundwater for the investigated elements with respect to sensitivity, replication, and portability, although DGT requires further evaluation in a wider range of groundwater environments and conditions. [ABSTRACT FROM AUTHOR]

The article presents views of Ian Harebottle, chief executive officer (CEO) at colored gemstones producer Gemfields, on the success of his firm. It mentions Gemfields clients appreciate the standards set by the company on emerald and ruby mining and distribution. It also mentions the Kagem emerald mine in Zambia has paid federal taxes.

In February 2014, the authors explored Sri Lanka's entire mine-to-market gemstone and jewelry industry. The team visited numerous mining, cutting, trading, jewelry manufacturing, and retail centers representing each sector and witnessed a dynamic blend of traditional and increasingly modern practices. Centuries of tradition as a colored gemstone mining, trading, and cutting source now converge with the technologies, skill sets, and strategies of today's global market. [ABSTRACT FROM AUTHOR]

We analyze the parallel performance of randomized interpolative decomposition by decomposing low rank complex-valued Gaussian random matrices of about 100 GB. We chose a Cray XMT supercomputer as it provides an almost ideal PRAM model permitting quick investigation of parallel algorithms without obfuscation from hardware idiosyncrasies. We obtain that on non-square matrices performance scales almost linearly with runtime about 100 times faster on 128 processors. We also verify that numerically discovered error bounds still hold on matrices two orders of magnitude larger than those previously tested. [ABSTRACT FROM AUTHOR]