Abstract
We present the Virgo Environment Traced in CO (VERTICO) survey, a new effort to map
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CO (2–1),
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CO (2–1), and C
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O (2–1) in 51 Virgo Cluster galaxies with the Atacama Compact Array, ...part of the Atacama Large Millimeter/submillimeter Array. The primary motivation of VERTICO is to understand the physical mechanisms that perturb molecular gas disks, and therefore star formation and galaxy evolution, in dense environments. This first paper contains an overview of VERTICO's design and sample selection,
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CO (2–1) observations, and data reduction procedures. We characterize global
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CO (2–1) fluxes and molecular gas masses for the 49 detected VERTICO galaxies, provide upper limits for the two nondetections, and produce resolved
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CO (2–1) data products (median resolution = 8″ ≈ 640 pc). Azimuthally averaged
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CO (2–1) radial intensity profiles are presented along with derived molecular gas radii. We demonstrate the scientific power of VERTICO by comparing the molecular gas size–mass scaling relation for our galaxies with a control sample of field galaxies, highlighting the strong effect that radius definition has on this correlation. We discuss the drivers of the form and scatter in the size–mass relation and highlight areas for future work. VERTICO is an ideal resource for studying the fate of molecular gas in cluster galaxies and the physics of environment-driven processes that perturb the star formation cycle. Upon public release, the survey will provide a homogeneous legacy data set for studying galaxy evolution in our closest cluster.
Abstract We study how environment regulates the star formation cycle of 33 Virgo Cluster satellite galaxies on 720 pc scales. We present the resolved star-forming main sequence for cluster galaxies, ...dividing the sample based on their global H i properties and comparing to a control sample of field galaxies. H i –poor cluster galaxies have reduced star formation rate (SFR) surface densities with respect to both H i –normal cluster and field galaxies (∼0.5 dex), suggesting that mechanisms regulating the global H i content are responsible for quenching local star formation. We demonstrate that the observed quenching in H i –poor galaxies is caused by environmental processes such as ram pressure stripping (RPS), simultaneously reducing the molecular gas surface density and star formation efficiency (SFE) compared to regions in H i –normal systems (by 0.38 and 0.22 dex, respectively). We observe systematically elevated SFRs that are driven by increased molecular gas surface densities at fixed stellar mass surface density in the outskirts of early stage RPS galaxies, while SFE remains unchanged with respect to the field sample. We quantify how RPS and starvation affect the star formation cycle of inner and outer galaxy disks as they are processed by the cluster. We show both are effective quenching mechanisms, with the key difference being that RPS acts upon the galaxy outskirts while starvation regulates the star formation cycle throughout disk, including within the truncation radius. For both processes, the quenching is caused by a simultaneous reduction in the molecular gas surface densities and SFE at fixed stellar mass surface density.
The accurate diagnosis of indeterminate pancreaticobiliary strictures presents a clinical dilemma. Probe-based confocal laser endomicroscopy (pCLE) offers real-time in vivo microscopic tissue ...examination that may increase sensitivity for the detection of malignancy. the objective of this study was to develop and validate a standard descriptive classification of pcle in the pancreaticobiliary system.
A total of 102 patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) with pCLE to assess indeterminate pancreaticobiliary strictures were enrolled in a multicenter registry; 89 of these patients were evaluable. Information and data on the following were collected prospectively: clinical, ERCP, tissue sampling, pCLE, and follow-up. A uniform classification of pCLE findings ("Miami Classification") was developed, consisting of a set of image interpretation criteria. Thereafter, these criteria were tested through blinded consensus review of 112 randomized pCLE videos from 47 patients, and inter-observer variability was assessed in 42 patients .
A consensus definition of the specific criteria of biliary and pancreatic pCLE findings for indeterminate strictures was developed. Single-image interpretation criteria did not have a high enough sensitivity for predicting malignancy. However, combining two or more criteria significantly increased the sensitivity and predictive values. The characteristics most suggestive of malignancy included the following: thick white bands (>20 µm), or thick dark bands (>40 µm), or dark clumps or epithelial structures. These provided sensitivity, specificity, positive predictive value, and negative predictive value of 97%, 33%, 80%, and 80% compared with 48%, 100%, 100%, and 41% for standard tissue sampling methods. Inter-observer variability was moderate for most criteria.
The Miami Classification enables a structured, uniform, and reproducible description of pancreaticobiliary pCLE. Combining individual characteristics improves the sensitivity for the detection of malignancy.
The ornamental fish trade is estimated to handle up to 1·5 billion fishes. Transportation and handling of fishes imposes a range of stressors that can result in mortality at rates of up to 73%. These ...rates vary hugely, however, and can be as low as 2%, because they are generally estimated rather than based on experimental work. Given the numbers of ornamental fishes traded, any of the estimated mortality rates potentially incur significant financial losses and serious welfare issues. Industry bodies, such as the Ornamental Aquatic Trade Association (OATA), have established standards and codes of best practice for handling fishes, but little scientific research has been conducted to understand the links between stress, health and welfare in ornamental species. In aquaculture, many of the same stressors occur as those in the ornamental trade, including poor water quality, handling, transportation, confinement, poor social and physical environment and disease and in this sector directed research and some resulting interventions have resulted in improved welfare standards. This review considers the concept of welfare in fishes and evaluates reported rates of mortality in the ornamental trade. It assesses how the stress response can be quantified and used as a welfare indicator in fishes. It then analyses whether lessons from aquaculture can be usefully applied to the ornamental fish industry to improve welfare. Finally, this analysis is used to suggest how future research might be directed to help improve welfare in the ornamental trade.
Results are presented from a matrix of coupled model integrations, using atmosphere resolutions of 135 and 90 km, and ocean resolutions of 1° and 1/3°, to study the impact of resolution on simulated ...climate. The mean state of the tropical Pacific is found to be improved in the models with a higher ocean resolution. Such an improved mean state arises from the development of tropical instability waves, which are poorly resolved at low resolution; these waves reduce the equatorial cold tongue bias. The improved ocean state also allows for a better simulation of the atmospheric Walker circulation.
Several sensitivity studies have been performed to further understand the processes involved in the different component models. Significantly decreasing the horizontal momentum dissipation in the coupled model with the lower-resolution ocean has benefits for the mean tropical Pacific climate, but decreases model stability. Increasing the momentum dissipation in the coupled model with the higher-resolution ocean degrades the simulation toward that of the lower-resolution ocean.
These results suggest that enhanced ocean model resolution can have important benefits for the climatology of both the atmosphere and ocean components of the coupled model, and that some of these benefits may be achievable at lower ocean resolution, if the model formulation allows.
This paper presents the production of a 3D cotton-wool-like structured inorganic fibrous material for bone regeneration electrospun from a sol–gel precursor solution. The fibrous material possesses ...interconnected nano to macro pores, large surface area and high porosity. The cotton-wool-like structured material is moldable which means it could easily be packed into complex bone defects. Display omitted
Inorganic sol–gel solutions were electrospun to produce the first bioactive three-dimensional (3-D) scaffolds for bone tissue regeneration with a structure like cotton-wool (or cotton candy). This flexible 3-D fibrous structure is ideal for packing into complex defects. It also has large inter-fiber spaces to promote vascularization, penetration of cells and transport of nutrients throughout the scaffold. The 3-D fibrous structure was obtained by electrospinning, where the applied electric field and the instabilities exert tremendous force on the spinning jet, which is required to be viscoelastic to prevent jet break up. Previously, polymer binding agents were used with inorganic solutions to produce electrospun composite two-dimensional fibermats, requiring calcination to remove the polymer. This study presents novel reaction and processing conditions for producing a viscoelastic inorganic sol–gel solution that results in fibers by the entanglement of the intermolecularly overlapped nanosilica species in the solution, eliminating the need for a binder. Three-dimensional cotton-wool-like structures were only produced when solutions containing calcium nitrate were used, suggesting that the charge of the Ca2+ ions had a significant effect. The resulting bioactive silica fibers had a narrow diameter range of 0.5–2μm and were nanoporous. A hydroxycarbonate apatite layer was formed on the fibers within the first 12h of soaking in simulated body fluid. MC3T3-E1 preosteoblast cells cultured on the fibers showed no adverse cytotoxic effect and they were observed to attach to and spread in the material.
We examine Robert MacArthur’s hypothesis that niche breadth is positively associated with latitude (the latitude–niche breadth hypothesis). This idea has been influential and long standing, yet no ...studies have evaluated its generality or the validity of its assumptions. We review the theoretical arguments suggesting a positive relationship between niche breadth and latitude. We also use available evidence to evaluate the assumptions and predictions of MacArthur’s latitude–niche breadth hypothesis. We find that neither the assumptions nor the predictions of the hypothesis are supported by data. We propose an alternative hypothesis linking latitude with niche breadth. Unlike previous ideas, our conceptual framework does not require equilibrial assumptions and is based on recently uncovered patterns of species interactions.
The relative importance of common activities on indoor nitrous acid (HONO) mixing ratios was explored during high time resolution, month-long measurements by chemical ionization mass spectrometry in ...a previously unoccupied house. Indoor HONO varied from 0.2 to 84.0 ppb (mean: 5.5 ppb; median 3.8 ppb), an order of magnitude higher than simultaneously measured outdoor values, indicating important indoor sources. They agree well with simultaneous measurements of HONO by Laser-Photofragmentation/Laser-Induced Fluorescence. Before any combustion activities, the mixing ratio of 3.0 ± 0.3 ppb is indicative of secondary sources such as multiphase formation from NO
. Cooking (with propane gas), especially the use of an oven, led to significant enhancements up to 84 ppb, with elevated mixing ratios persisting for a few days due to slow desorption from indoor surface reservoirs. Floor bleach cleaning led to prolonged, substantial decreases of up to 71-90% due to reactive processes. Air conditioning modulated HONO mixing ratios driven by condensation to wet surfaces in the AC unit. Enhanced ventilation also significantly lowered mixing ratios. Other conditions including human occupancy, ozone addition, and cleaning with terpene, natural product, and vinegar cleaners had a much smaller influence on HONO background levels measured following these activities.
PH domain leucine-rich-repeats protein phosphatase (PHLPP) is a family of Ser/Thr protein phosphatases that serve as tumor suppressors by negatively regulating Akt. Our recent studies have ...demonstrated that the ubiquitin proteasome pathway has an important role in the downregulation of PHLPP in colorectal cancer. In this study, we show that the deubiquitinase USP46 stabilizes the expression of both PHLPP isoforms by reducing the rate of PHLPP degradation. USP46 binds to PHLPP and directly removes the polyubiquitin chains from PHLPP in vitro and in cells. Increased USP46 expression correlates with decreased ubiquitination and upregulation of PHLPP proteins in colon cancer cells, whereas knockdown of USP46 has the opposite effect. Functionally, USP46-mediated stabilization of PHLPP and the subsequent inhibition of Akt result in a decrease in cell proliferation and tumorigenesis of colon cancer cells in vivo. Moreover, reduced USP46 protein level is found associated with poor PHLPP expression in colorectal cancer patient specimens. Taken together, these results indentify a tumor suppressor role of USP46 in promoting PHLPP expression and inhibiting Akt signaling in colon cancer.
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