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Salmonella invades and disrupts gut epithelium integrity, creating an infection-generated electric field that can drive directional migration of macrophages, a process called galvanotaxis. Phagocytosis of bacteria reverses the direction of macrophage galvanotaxis, implicating a bioelectrical mechanism to initiate life-threatening disseminations. The force that drives direction reversal of macrophage galvanotaxis is not understood. One hypothesis is that Salmonella can alter the electrical properties of the macrophages by modifying host cell surface glycan composition, which is supported by the fact that cleavage of surface-exposed sialic acids with a bacterial neuraminidase severely impairs macrophage galvanotaxis, as well as phagocytosis. Here, we utilize N-glycan profiling by nanoLC-chip QTOF mass cytometry to characterize the bacterial neuraminidase-associated compositional shift of the macrophage glycocalyx, which revealed a decrease in sialylated and an increase in fucosylated and high mannose structures. The Salmonella nanH gene, encoding a putative neuraminidase, is required for invasion and internalization in a human colonic epithelial cell infection model. To determine whether NanH is required for the Salmonella infection-dependent direction reversal, we constructed and characterized a nanH deletion mutant and found that NanH is partially required for Salmonella infection in primary murine macrophages. However, compared to wild type Salmonella, infection with the nanH mutant only marginally reduced the cathode-oriented macrophage galvonotaxis, without canceling direction reversal. Together, these findings strongly suggest that while neuraminidase-mediated N-glycan modification impaired both macrophage phagocytosis and galvanotaxis, yet to be defined mechanisms other than NanH may play a more important role in bioelectrical control of macrophage trafficking, which potentially triggers dissemination.

Background: Americas Hepato-Pancreato-Biliary Association (AHPBA) established the Hepato-Pancreato-Biliary (HPB) ultrasound (US) and Advanced Technology Post-Graduate Course in 2012 in response to a perceived gap in training and practice. Methods: The HPB US and Advanced Technology Post-Graduate Course consists of both didactic and hands-on skills sessions. The didactic sessions are divided into foundational, organ-focused, and application content. Hands-on sessions are constructed to immediately practice skills in the simulation setting which were taught during the didactic sessions. Course participant demographic data (practice location and practice type) and participant evaluations were reported. Results: Since the first course in 2012, 298 participants have taken the post-graduate course. Most participants reported the content quality, delivery effectiveness, and practice relevance to be either excellent or above average (93.6 %, 91.1 %, 93.6 %, respectively). Participants' motivations to take the course included to enhance skills, knowledge, to incorporate US into practice, or to obtain formal training or qualification/certification, or to teach. Conclusion: The HPB US and Advanced Technology Post-Graduate Course has filled a gap in HPB US training for practicing HPB surgeons. The annual course has been well-received by participants (Kirkpatrick Level 1 Program Evaluation) and will continue to fill the gap in training in operative US for the HPB surgeon. Key message: Americas Hepato-Pancreato-Biliary Association established the HPB Ultrasound and Advanced Technology Post-Graduate Course in 2012. The Course has been well-received by participants and will continue to address a gap in surgical HPB training.

Maintaining and restoring freshwater ecosystem services in the face of local and global change requires adaptive research that effectively engages stakeholders. However, there is a lack of understanding and consensus in the research community regarding where, when, and which stakeholders should be engaged and what kind of researcher should do the engaging (e.g., physical, ecological, or social scientists). This paper explores stakeholder engagement across a developing network of aquatic research sites in North and South America with wide ranging cultural norms, social values, resource management paradigms, and eco-physical conditions. With seven sites in six countries, we found different degrees of engagement were explained by differences in the interests of the stakeholders given the history and perceived urgency of water resource problems as well as differences in the capacities of the site teams to effectively engage given their expertise and resources. We categorized engagement activities and applied Hurlbert and Gupta's split ladder of participation to better understand site differences and distill lessons learned for planning comparative socio-hydrological research and systematic evaluations of the effectiveness of stakeholder engagement approaches. We recommend research networks practice deliberate engagement of stakeholders that adaptively accounts for variations and changes in local socio-hydrologic conditions. This, in turn, requires further efforts to foster the development of well-integrated research teams that attract and retain researchers from multiple social science disciplines and enable training on effective engagement strategies for diverse conditions.

ABSTRACTMotile cells migrate directionally in the electric field in a process known as galvanotaxis. Galvanotaxis is important in wound healing, development, cell division, and nerve growth. Different cell types migrate in opposite directions in electric fields, to either cathode, or anode, and the same cell can switch the directionality depending on chemical conditions. We previously reported that individual fish keratocyte cells sense electric fields and migrate to the cathode, while inhibition of PI3K reverses single cells to the anode. Many physiological processes rely on collective, not individual, cell migration, so here we report on directional migration of cohesive cell groups in electric fields. Uninhibited cell groups of any size move to the cathode, with speed decreasing and directionality increasing with the group size. Surprisingly, large groups of PI3K-inhibited cells move to the cathode, in the direction opposite to that of individual cells, which move to the anode, while such small groups are not persistently directional. In the large groups, cells’ velocities are distributed unevenly: the fastest cells are at the front of the uninhibited groups, but at the middle and rear of the PI3K-inhibited groups. Our results are most consistent with the hypothesis, supported by the computational model, that cells inside and at the edge of the groups interpret directional signals differently. Namely, cells in the group interior are directed to the cathode independently of their chemical state. Meanwhile, edge cells behave like the individual cells: they are directed to the cathode/anode in uninhibited/PI3K-inhibited groups, respectively. As a result, all cells drive uninhibited groups to the cathode, but a mechanical tug-of-war between the inner and edge cells directs large PI3K-inhibited groups with cell majority in the interior to the cathode, while rendering small groups non-directional.Significance statementMotile cells migrate directionally in electric fields. This behavior – galvanotaxis – is important in many physiological phenomena. Individual fish keratocytes migrate to the cathode, while inhibition of PI3K reverses single cells to the anode. Uninhibited cell groups move to the cathode. Surprisingly, large groups of PI3K-inhibited cells also move to the cathode, in the direction opposite to that of individual cells. The fastest cells are at the front of the uninhibited groups, but at the middle and rear of the PI3K-inhibited groups. We posit that inner and edge cells interpret directional signals differently, and that a tug-of-war between the edge and inner cells directs the cell groups. These results shed light on general principles of collective cell migration.

Background: Ultrasound is an essential tool for the hepatobiliary and pancreatic surgeon. Methods: This review focuses on transabdominal, open intraoperative, and laparoscopic ultrasonography of the liver, biliary tract, and pancreas. The goal is to obtain optimal ultrasound images through an understanding of the equipment setup, transducer (probe) selection, terminology, and general scanning principles. Outlined is a structured, standardized approach necessary to obtain complete information when doing intraoperative ultrasound. When done by the surgeon, the goal of the examination typically is to answer a question or questions through a focused rather than a comprehensive diagnostic examination. Finally, presented are the details of techniques specific to scanning each of the major organs. Results: A structured, standardized ultrasound scanning approach provides for optimal image acquisition. It allows one to develop standardized views of common structures resulting in ''pattern recognition,'' making learning and interpreting images easier. A standardized approach ensures a complete ultrasound examination, and it minimizes the chance of missed findings. Summary: The general principles for transabdominal, open intraoperative, and laparoscopic ultrasonography scanning are similar. One can gather considerable information using these modalities during a clinical examination, procedure, or operation. For success, it is critical to develop a standardized approach to scanning and use it every time. This facilitates familiarity when viewing images, making it easier for the novice to learn and gain experience. Using a systematic approach ensures that the experienced ultrasonographer obtains all the essential information needed at the time of surgery.

Have U.S. oil market policy interventions succeeded in lowering the price of crude oil? This paper uses a structural vector autoregression model of the U.S. oil market to estimate the effect of purchases and releases by the Strategic Petroleum Reserve (SPR). Unanticipated releases from the SPR have no measurable impact on oil prices, but unanticipated purchases for the SPR raise oil prices by about 1 percent. These results are robust to identification using external instruments. Keywords: Energy Prices, Oil and the Macroeconomy, Government Policy, Oil Shocks, 1. INTRODUCTION The Strategic Petroleum Reserve (SPR) was created in response to the 1973-1974 oil embargo by the Organization of the Petroleum Exporting Countries, and was intended to 'store petroleum [...]

Abstract The use of machine learning technologies to process large quantities of remotely collected audio data is a powerful emerging research tool in ecology and conservation. We applied these methods to a field study of tinamou (Tinamidae) biology in Madre de Dios, Peru, a region expected to have high levels of interspecies competition and niche partitioning as a result of high tinamou alpha diversity. We used autonomous recording units to gather environmental audio over a period of several months at lowland rainforest sites in the Los Amigos Conservation Concession and developed a Convolutional Neural Network‐based data processing pipeline to detect tinamou vocalizations in the dataset. The classified acoustic event data are comparable to similar metrics derived from an ongoing camera trapping survey at the same site, and it should be possible to combine the two datasets for future explorations of the target species' niche space parameters. Here, we provide an overview of the methodology used in the data collection and processing pipeline, offer general suggestions for processing large amounts of environmental audio data, and demonstrate how data collected in this manner can be used to answer questions about bird biology.

We present baryon acoustic oscillation (BAO) scale measurements determined from the clustering of 1.2 million massive galaxies with redshifts 0.2 < z < 0.75 distributed over 9300 deg2, as quantified by their redshift-space correlation function. In order to facilitate these measurements, we define, describe, and motivate the selection function for galaxies in the final data release (DR12) of the SDSS III Baryon Oscillation Spectroscopic Survey (BOSS). This includes the observational footprint, masks for image quality and Galactic extinction, and weights to account for density relationships intrinsic to the imaging and spectroscopic portions of the survey. We simulate the observed systematic trends in mock galaxy samples and demonstrate that they impart no bias on BAO scale measurements and have a minor impact on the recovered statistical uncertainty. We measure transverse and radial BAO distance measurements in 0.2 < z < 0.5, 0.5 < z < 0.75, and (overlapping) 0.4 < z < 0.6 redshift bins. In each redshift bin, we obtain a precision that is 2.7 per cent or better on the radial distance and 1.6 per cent or better on the transverse distance. The combination of the redshift bins represents 1.8 per cent precision on the radial distance and 1.1 per cent precision on the transverse distance. This paper is part of a set that analyses the final galaxy clustering data set from BOSS. The measurements and likelihoods presented here are combined with others in Alam et al. to produce the final cosmological constraints from BOSS.

As part of a collaborative research effort (The NHERI TallWood Project), an extensive shake table test program was undertaken on a full-scale 10-story mass timber building with a resilient posttensioned mass timber rocking wall lateral system. Over a three-year period, academic and industry partners collaborated on the design, construction, and testing of a 34 m (113 ft) tall, 10-story mass timber building at the world's largest outdoor shake table facility (NHERI@UC San Diego). The test building incorporated a resilient mass timber rocking wall lateral system, gravity connection details designed to remain damage-free under design level earthquakes as well as innovative nonstructural systems detailed to tolerate moderate building drifts without significant damage. A total of 88 earthquake tests at different intensity levels were conducted, including several at the risk targeted maximum considered earthquake intensity for the building's design location. Experimental results indicate that a tall wood building with the systems and details employed in this study can withstand design basis and maximum considered earthquake level events repeatedly with no notable residual drift, no structural member or connection damage, while only experiencing moderate nonstructural damage that would be repairable, meeting the intended resilience goals. This paper provides a summary of the design, construction, testing, and primary results from this experimental program. [ABSTRACT FROM AUTHOR]

Why do some coercive demands succeed but others fail? A dominant paradigm explains coercive outcomes by pointing to the credibility and severity of threats. The concept of coercive assurance is an understudied type of commitment problem in the coercion literature. It suggests that a coercer must assure its target that its threats are conditional on the target's behavior. Many scholars overlook coercive assurance, in part because they assume it is automatic. But assurance is a crucial component of any coercive process. Even highly credible and severe threats can fail when the coercer's assurance is not credible. A novel theory, the assurance dilemma, helps to answer the following questions: Why do targets of coercion fear unconditional pain? Why do coercers punish after receiving compliance? What is the relationship between threats and assurances in coercion? The actions that a coercer can take to bolster the credibility of a threat undermine the credibility of its assurance that it will not punish the target. Targets fear that punishment may be unavoidable and thus look for assuring signals before ceding to the coercer's demands. The case of coercive bargaining over the Iranian nuclear program demonstrates the logic and effectiveness of the use of assurance. [ABSTRACT FROM AUTHOR]

We describe the algorithm used to select the luminous red galaxy (LRG) sample for the extended Baryon Oscillation Spectroscopic Survey (eBOSS) of the Sloan Digital Sky Survey IV (SDSS-IV) using photometric data from both the SDSS and the Wide-field Infrared Survey Explorer. LRG targets are required to meet a set of color selection criteria and have z-band and i-band MODEL magnitudes z < 19.95 and 19.9 < i < 21.8, respectively. Our algorithm selects roughly 50 LRG targets per square degree, the great majority of which lie in the redshift range 0.6 < z < 1.0 (median redshift 0.71). We demonstrate that our methods are highly effective at eliminating stellar contamination and lower-redshift galaxies. We perform a number of tests using spectroscopic data from SDSS-III/BOSS ancillary programs to determine the redshift reliability of our target selection and its ability to meet the science requirements of eBOSS. The SDSS spectra are of high enough signal-to-noise ratio that at least ∼89% of the target sample yields secure redshift measurements. We also present tests of the uniformity and homogeneity of the sample, demonstrating that it should be clean enough for studies of the large-scale structure of the universe at higher redshifts than SDSS-III/BOSS LRGs reached.

The Baryon Oscillation Spectroscopic Survey (BOSS), part of the Sloan Digital Sky Survey (SDSS) III project, has provided the largest survey of galaxy redshifts available to date, in terms of both the number of galaxy redshifts measured by a single survey, and the effective cosmological volume covered. Key to analysing the clustering of these data to provide cosmological measurements is understanding the detailed properties of this sample. Potential issues include variations in the target catalogue caused by changes either in the targeting algorithm or properties of the data used, the pattern of spectroscopic observations, the spatial distribution of targets for which redshifts were not obtained, and variations in the target sky density due to observational systematics. We document here the target selection algorithms used to create the galaxy samples that comprise BOSS. We also present the algorithms used to create large-scale structure catalogues for the final Data Release (DR12) samples and the associated random catalogues that quantify the survey mask. The algorithms are an evolution of those used by the BOSS team to construct catalogues from earlier data, and have been designed to accurately quantify the galaxy sample. The code used, designated MKSAMPLE, is released with this paper.

We derive constraints on cosmological parameters and tests of dark energy models from the combination of baryon acoustic oscillation (BAO) measurements with cosmic microwave background (CMB) data and a recent reanalysis of Type Ia supernova (SN) data. In particular, we take advantage of high-precision BAO measurements from galaxy clustering and the Lyman-α forest (LyaF) in the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). Treating the BAO scale as an uncalibrated standard ruler, BAO data alone yield a high confidence detection of dark energy; in combination with the CMB angular acoustic scale they further imply a nearly flat universe. Adding the CMB-calibrated physical scale of the sound horizon, the combination of BAO and SN data into an "inverse distance ladder" yields a measurement of H0=67.3±1.1 km s-1 Mpc-1, with 1.7% precision. This measurement assumes standard prerecombination physics but is insensitive to assumptions about dark energy or space curvature, so agreement with CMB-based estimates that assume a flat ΛCDM cosmology is an important corroboration of this minimal cosmological model. For constant dark energy (Λ), our BAO+SN+CMB combination yields matter density Ωm=0.301±0.008 and curvature Ωk=-0.003±0.003. When we allow more general forms of evolving dark energy, the BAO+SN+CMB parameter constraints are always consistent with flat ΛCDM values at ≈1σ. While the overall χ2 of model fits is satisfactory, the LyaF BAO measurements are in moderate (2-2.5σ) tension with model predictions. Models with early dark energy that tracks the dominant energy component at high redshift remain consistent with our expansion history constraints, and they yield a higher H0 and lower matter clustering amplitude, improving agreement with some low redshift observations. Expansion history alone yields an upper limit on the summed mass of neutrino species, mν

Observations of redshift-space distortions in spectroscopic galaxy surveys offer an attractive method for observing the build-up of cosmological structure, which depends both on the expansion rate of the Universe and our theory of gravity. In preparation for analysis of redshiftspace distortions from the Baryon Oscillation Spectroscopic Survey (BOSS) final data release, we compare a number of analytic and phenomenological models, specified in configuration space, to mock catalogues derived in different ways from several N-body simulations. The galaxies in each mock catalogue have properties similar to those of the higher redshift galaxies measured by BOSS but differ in the details of how small-scale velocities and halo occupancy are determined. We find that all of the analytic models fit the simulations over a limited range of scales while failing at small scales.We discuss which models are most robust and on which scales they return reliable estimates of the rate of growth of structure: we find that models based on some form of resummation can fit our N-body data for BOSS-like galaxies above 30 h-1 Mpc well enough to return unbiased parameter estimates.

Breaching of the cell membrane is one of the earliest and most common causes of cell injury, tissue damage, and disease. If the compromise in cell membrane is not repaired quickly, irreversible cell damage, cell death and defective organ functions will result. It is therefore fundamentally important to efficiently repair damage to the cell membrane. While the molecular aspects of single cell wound healing are starting to be deciphered, its bio-physical counterpart has been poorly investigated. Using Xenopus laevis oocytes as a model for single cell wound healing, we describe the temporal and spatial dynamics of the wound electric current circuitry and the temporal dynamics of cell membrane potential variation. In addition, we show the role of calcium influx in controlling electric current circuitry and cell membrane potential variations. (i) Upon wounding a single cell: an inward electric current appears at the wound center while an outward electric current is observed at its sides, illustrating the wound electric current circuitry; the cell membrane is depolarized; calcium flows into the cell. (ii) During cell membrane re-sealing: the wound center current density is maintained for a few minutes before decreasing; the cell membrane gradually re-polarizes; calcium flow into the cell drops. (iii) In conclusion, calcium influx is required for the formation and maintenance of the wound electric current circuitry, for cell membrane re-polarization and for wound healing. This journal is © the Partner Organisations 2014.

We present a one per cent measurement of the cosmic distance scale from the detections of the baryon acoustic oscillations (BAO) in the clustering of galaxies from the Baryon Oscillation Spectroscopic Survey, which is part of the Sloan Digital Sky Survey III. Our results come from the Data Release 11 (DR11) sample, containing nearly one million galaxies and covering approximately 8500 square degrees and the redshift range 0.2 < z < 0.7. We also compare these results with those from the publicly released DR9 and DR10 samples. Assuming a concordance Λ cold dark matter (ΛCDM) cosmological model, the DR11 sample covers a volume of 13 Gpc3 and is the largest region of the Universe ever surveyed at this density. We measure the correlation function and power spectrum, including density-field reconstruction of the BAO feature. The acoustic features are detected at a significance of over 7σ in both the correlation function and power spectrum. Fitting for the position of the acoustic features measures the distance relative to the sound horizon at the drag epoch, rd, which has a value of rd,fid = 149.28 Mpc in our fiducial cosmology. We find DV = (1264 ± 25 Mpc)(rd/rd,fid) at z = 0.32 and DV = (2056 ± 20 Mpc)(rd/rd,fid) at z = 0.57. At 1.0 per cent, this latter measure is the most precise distance constraint ever obtained from a galaxy survey. Separating the clustering along and transverse to the line of sight yields measurements at z = 0.57 of DA = (1421 ± 20 Mpc)(rd/rd,fid) and H = (96.8 ± 3.4 kms-1 Mpc-1)(rd,fid/rd). Our measurements of the distance scale are in good agreement with previous BAO measurements and with the predictions from cosmic microwave background data for a spatially flat CDM model with a cosmological constant. © 2014 The Author Published by Oxford University Press on behalf of the Royal Astronomical Society.

We present the distance measurement to z = 0.32 using the eleventh data release (DR) of the Sloan Digital Sky Survey-III Baryon Acoustic Oscillation Survey (BOSS). We use 313 780 galaxies of the low-redshift (LOWZ) sample over 7341 square degrees to compute Dv = (1264±25)(rd/rd,fid) - a sub 2 per cent measurement - using the baryon acoustic feature measured in the galaxy two-point correlation function and power spectrum. We compare our results to those obtained in DR10. We study observational systematics in the LOWZ sample and quantify potential effects due to photometric offsets between the northern and southern Galactic caps. We find the sample to be robust to all systematic effects found to impact on the targeting of higher redshift BOSS galaxies and that the observed north-south tensions can be explained by either limitations in photometric calibration or by sample variance, and have no impact on our final result. Our measurement, combined with the baryonic acoustic scale at z = 0.57, is used in Anderson et al. to constrain cosmological parameters. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Understanding the formation and evolution of large-scale structure is a central problem in cosmology and enables precise tests of General Relativity on cosmological scales and constraints on dark energy. An essential ingredient is an accurate description of the pairwise velocities of biased tracers of the matter field. In this paper, we compute the first and second moments of the pairwise velocity distribution by extending the convolution Lagrangian perturbation theory (CLPT) formalism of Carlson et al. Our predictions outperform standard perturbation theory calculations in many cases when compared to statistics measured in N-body simulations. We combine the CLPT predictions of real-space clustering and velocity statistics in the Gaussian streaming model of Reid & White to obtain predictions for the monopole and quadrupole correlation functions accurate to 2 and 4 per cent, respectively, down to < 25 h-1 Mpc for haloes hosting the massive galaxies observed by SDSS-III BOSS.We also discuss contours of the 2D correlation function and clustering 'wedges'. We generalize the scheme to cross-correlation functions. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.