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We have detected 27 new supernova remnants (SNRs) using a new data release of the GLEAM survey from the Murchison Widefield Array telescope, including the lowest surface brightness SNR ever detected, G 0.1 – 9.7. Our method uses spectral fitting to the radio continuum to derive spectral indices for 26/27 candidates, and our low-frequency observations probe a steeper spectrum population than previously discovered. None of the candidates have coincident WISE mid-IR emission, further showing that the emission is non-thermal. Using pulsar associations we derive physical properties for six candidate SNRs, finding G 0.1 – 9.7 may be younger than 10 kyr. Sixty per cent of the candidates subtend areas larger than 0.2 deg2 on the sky, compared to < 25% of previously detected SNRs. We also make the first detection of two SNRs in the Galactic longitude range 220°–240°.
This work makes available a further
of the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey, covering half of the accessible galactic plane, across 20 frequency bands sampling 72–231 MHz, with resolution
. Unlike previous GLEAM data releases, we used multi-scale CLEAN to better deconvolve large-scale galactic structure. For the galactic longitude ranges
$345^\circ < l < 67^\circ$
$180^\circ < l < 240^\circ$
, we provide a compact source catalogue of 22 037 components selected from a 60-MHz bandwidth image centred at 200 MHz, with RMS noise
and position accuracy better than 2 arcsec. The catalogue has a completeness of 50% at
, and a reliability of 99.86%. It covers galactic latitudes
towards the galactic centre and
for other regions, and is available from Vizier; images covering
for all longitudes are made available on the GLEAM Virtual Observatory (VO).server and SkyView.
We examined the latest data release from the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey covering 345° < l < 60° and 180° < l < 240°, using these data and that of the Widefield Infrared Survey Explorer to follow up proposed candidate Supernova Remnant (SNR) from other sources. Of the 101 candidates proposed in the region, we are able to definitively confirm ten as SNRs, tentatively confirm two as SNRs, and reclassify five as H ii regions. A further two are detectable in our images but difficult to classify; the remaining 82 are undetectable in these data. We also investigated the 18 unclassified Multi-Array Galactic Plane Imaging Survey (MAGPIS) candidate SNRs, newly confirming three as SNRs, reclassifying two as H ii regions, and exploring the unusual spectra and morphology of two others.
The work described in this research communication aimed to investigate whether rumen-protected methionine (Met) supplementation during the periparturient period would affect the expression of galectins in blood-derived neutrophils, and secretion of galectins, IL (interleukin)-1β, IL-6, myeloperoxidase (MPO), and glucose in plasma. Because supplementation of rumen-protected Met would alleviate inflammation and oxidative stress during the peripartal period, we hypothesized that enhancing Met supply would benefit the innate immune response at least in part by altering the expression of galectin genes associated with neutrophil activity and inflammation. Galectins (Gal) have an immuno-modulating effect acting like cell-surface receptors whose activation often results in signaling cascades stimulating cells such as neutrophils. This study revealed an association between Met supplementation and galectin expression and secretion. This implies that galectin expression and secretion can be modulated by Met supplementation. Further studies are needed to evaluate the regulation of galectin gene expression for therapeutic and dietary intervention in the peripartal cow.
Many institutions evaluate applications for local seed funding by recruiting peer reviewers from their own institutional community. Smaller institutions, however, often face difficulty locating qualified local reviewers who are not in conflict with the proposal. As a larger pool of reviewers may be accessed through a cross-institutional collaborative process, nine Clinical and Translational Science Award (CTSA) hubs formed a consortium in 2016 to facilitate reviewer exchanges. Data were collected to evaluate the feasibility and preliminary efficacy of the consortium.
The CTSA External Reviewer Exchange Consortium (CEREC) has been supported by a custom-built web-based application that facilitates the process and tracks the efficiency and productivity of the exchange.
All nine of the original CEREC members remain actively engaged in the exchange. Between January 2017 and May 2019, CEREC supported the review process for 23 individual calls for proposals. Out of the 412 reviews requested, 368 were received, for a fulfillment ratio of 89.3%. The yield on reviewer invitations has remained consistently high, with approximately one-third of invitations being accepted, and of the reviewers who agreed to provide a review, 88.3% submitted a complete review. Surveys of reviewers and pilot program administrators indicate high satisfaction with the process.
These data indicate that a reviewer exchange consortium is feasible, adds value to participating partners, and is sustainable over time.
In evaluating the quality of table eggs and the developmental stages of embryonic eggs, spectroscopic techniques provide greater efficiency than traditional, time-consuming and laborious approaches. This review summarises recent developments in the spectroscopic analysis of table eggs, including the determination of the chemical composition (ratios of performance to standard deviation of 4.38, 2.25, 2.28, 2.31, and 3.03 for fat, moisture, and protein in egg yolk and moisture and protein in egg albumen, respectively, have been reported). A Haugh unit detection accuracy RMSEP (root mean square error of prediction) for quality of 6.29 was obtained by hyperspectral imaging) for table eggs and fertility detection (for white-shell eggs, fertility detection has been realised at a promising rate of 93.5%) and gender determination in hatching eggs. In conclusion, hyperspectral imaging generally outperforms visible or near-infrared reflectance spectroscopy when evaluating both consumption eggs and hatching eggs, and near-infrared reflectance Raman and fluorescence spectroscopy exhibit a strong potential for gender determination prior to hatching. Scientists have attained a correct sexing rate above 90% at 3.5 d of egg incubation without removing the inner shell membrane. In the detection of blood-spot eggs or fertile eggs, eggshell colour proved to be a negative factor.
We apply two methods to estimate the 21-cm bispectrum from data taken within the Epoch of Reionisation (EoR) project of the Murchison Widefield Array (MWA). Using data acquired with the Phase II compact array allows a direct bispectrum estimate to be undertaken on the multiple redundantly spaced triangles of antenna tiles, as well as an estimate based on data gridded to the uv-plane. The direct and gridded bispectrum estimators are applied to 21 h of high-band (167–197 MHz; z = 6.2–7.5) data from the 2016 and 2017 observing seasons. Analytic predictions for the bispectrum bias and variance for point-source foregrounds are derived. We compare the output of these approaches, the foreground contribution to the signal, and future prospects for measuring the bispectra with redundant and non-redundant arrays. We find that some triangle configurations yield bispectrum estimates that are consistent with the expected noise level after 10 h, while equilateral configurations are strongly foreground-dominated. Careful choice of triangle configurations may be made to reduce foreground bias that hinders power spectrum estimators, and the 21-cm bispectrum may be accessible in less time than the 21-cm power spectrum for some wave modes, with detections in hundreds of hours.
While assessing the environmental impact of nuclear power plants, researchers have focused their attention on radiocarbon (14C) owing to its high mobility in the environment and important radiological impact on human beings. The 10 MW high-temperature gas-cooled reactor (HTR-10) is the first pebble-bed gas-cooled test reactor in China that adopted helium as primary coolant and graphite spheres containing tristructural-isotropic (TRISO) coated particles as fuel elements. A series of experiments on the 14C source terms in HTR-10 was conducted: (1) measurement of the specific activity and distribution of typical nuclides in the irradiated graphite spheres from the core, (2) measurement of the activity concentration of 14C in the primary coolant, and (3) measurement of the amount of 14C discharged in the effluent from the stack. All experimental data on 14C available for HTR-10 were summarized and analyzed using theoretical calculations. A sensitivity study on the total porosity, open porosity, and percentage of closed pores that became open after irradiating the matrix graphite was performed to illustrate their effects on the activity concentration of 14C in the primary coolant and activity amount of 14C in various deduction routes.
Two-dimensional particle-in-cell (PIC) simulations have been used to investigate the interaction between a laser pulse and a foil exposed to an external strong longitudinal magnetic field. Compared with that in the absence of the external magnetic field, the divergence of proton with the magnetic field in radiation pressure acceleration (RPA) regimes has improved remarkably due to the restriction of the electron transverse expansion. During the RPA process, the foil develops into a typical bubble-like shape resulting from the combined action of transversal ponderomotive force and instabilities. However, the foil prefers to be in a cone-like shape by using the magnetic field. The dependence of proton divergence on the strength of magnetic field has been studied, and an optimal magnetic field of nearly 60 kT is achieved in these simulations.
The Chinese white pine beetle Dendroctonus armandi (Coleoptera: Scolytinae) typically displays bivoltinism at altitudes below 1700 m in the Qinling Mountains, China. The periods of host colonization and larval overwintering are two important phases in the life cycle of bark beetles, as it is during these periods that they have to contend with host plant defences and periods of intense cold, respectively. Although during different seasons, the females and males of Chinese white pine beetles show varying tolerances to host plant terpenoids, the sex ratio and survival physiology condition of the two beetle generations are unknown. We investigated the sex ratio of individuals, and also examined the body mass, energy stores, and detoxication enzymes of males and females in each of the two generations in order to determine the overall population stability of each generation. We identified a female-biased sex ratio among adults in both generations. Furthermore, patterns of body mass, energy stores, and detoxication enzymes were found to differ between the two sexes and two seasons. Compared with the males, the females have a larger body mass and higher amounts of stored lipids, which are assumed to be adaptations designed to overcome host resistance and facilitate subsequent oviposition.
Streamwise velocity and wall-shear stress are acquired simultaneously with a hot-wire and an array of azimuthal/spanwise-spaced skin friction sensors in large-scale pipe and boundary layer flow facilities at high Reynolds numbers. These allow for a correlation analysis on a per-scale basis between the velocity and reference skin friction signals to reveal which velocity-based turbulent motions are stochastically coherent with turbulent skin friction. In the logarithmic region, the wall-attached structures in both the pipe and boundary layers show evidence of self-similarity, and the range of scales over which the self-similarity is observed decreases with an increasing azimuthal/spanwise offset between the velocity and the reference skin friction signals. The present empirical observations support the existence of a self-similar range of wall-attached turbulence, which in turn are used to extend the model of Baars et al. (J. Fluid Mech., vol. 823, p. R2) to include the azimuthal/spanwise trends. Furthermore, the region where the self-similarity is observed correspond with the wall height where the mean momentum equation formally admits a self-similar invariant form, and simultaneously where the mean and variance profiles of the streamwise velocity exhibit logarithmic dependence. The experimental observations suggest that the self-similar wall-attached structures follow an aspect ratio of
in the streamwise, spanwise and wall-normal directions, respectively.
This study presents findings from a first-of-its-kind measurement campaign that includes simultaneous measurements of the full velocity and vorticity vectors in both pipe and boundary layer flows under matched spatial resolution and Reynolds number conditions. Comparison of canonical turbulent flows offers insight into the role(s) played by features that are unique to one or the other. Pipe and zero pressure gradient boundary layer flows are often compared with the goal of elucidating the roles of geometry and a free boundary condition on turbulent wall flows. Prior experimental efforts towards this end have focused primarily on the streamwise component of velocity, while direct numerical simulations are at relatively low Reynolds numbers. In contrast, this study presents experimental measurements of all three components of both velocity and vorticity for friction Reynolds numbers
ranging from 5000 to 10 000. Differences in the two transverse Reynolds normal stresses are shown to exist throughout the log layer and wake layer at Reynolds numbers that exceed those of existing numerical data sets. The turbulence enstrophy profiles are also shown to exhibit differences spanning from the outer edge of the log layer to the outer flow boundary. Skewness and kurtosis profiles of the velocity and vorticity components imply the existence of a ‘quiescent core’ in pipe flow, as described by Kwon et al. (J. Fluid Mech., vol. 751, 2014, pp. 228–254) for channel flow at lower
, and characterize the extent of its influence in the pipe. Observed differences between statistical profiles of velocity and vorticity are then discussed in the context of a structural difference between free-stream intermittency in the boundary layer and ‘quiescent core’ intermittency in the pipe that is detectable to wall distances as small as 5 % of the layer thickness.
Starch digestion in the small intestines of the dairy cow is low, to a large extent, due to a shortage of syntheses of α-amylase. One strategy to improve the situation is to enhance the synthesis of α-amylase. The mammalian target of rapamycin (mTOR) signalling pathway, which acts as a central regulator of protein synthesis, can be activated by leucine. Our objectives were to investigate the effects of leucine on the mTOR signalling pathway and to define the associations between these signalling activities and the synthesis of pancreatic enzymes using an in vitro model of cultured Holstein dairy calf pancreatic tissue. The pancreatic tissue was incubated in culture medium containing l-leucine for 3 h, and samples were collected hourly, with the control being included but not containing l-leucine. The leucine supplementation increased α-amylase and trypsin activities and the messenger RNA expression of their coding genes (P <0.05), and it enhanced the mTOR synthesis and the phosphorylation of mTOR, ribosomal protein S6 kinase 1 and eukaryotic initiation factor 4E-binding protein 1 (P <0.05). In addition, rapamycin inhibited the mTOR signal pathway factors during leucine treatment. In sum, the leucine regulates α-amylase and trypsin synthesis in dairy calves through the regulation of the mTOR signal pathways.
The strong-coupling mode, called the “quasimode”, is excited by stimulated Brillouin scattering (SBS) in high-intensity laser–plasma interactions. Also SBS of the quasimode competes with SBS of the fast mode (or slow mode) in multi-ion species plasmas, thus leading to a low-frequency burst behavior of SBS reflectivity. Competition between the quasimode and the ion-acoustic wave (IAW) is an important saturation mechanism of SBS in high-intensity laser–plasma interactions. These results give a clear explanation of the low-frequency periodic burst behavior of SBS and should be considered as a saturation mechanism of SBS in high-intensity laser–plasma interactions.
We report a roll-to-roll dry processing for making low cost and high performance electrodes for lithium-ion batteries (LIBs). Currently, the electrodes for LIBs are made with a slurry casting procedure (wet method). The dry electrode fabrication is a three-step process including: step 1 of uniformly mixing electrode materials powders comprising an active material, a carbonaceous conductor and the soft polymer binder; step 2 of forming a free-standing, continuous electrode film by pressing the mixed powders together through the gap between two rolls of a roll-mill; and step 3 of roll-to-roll laminating the electrode film onto a substrate such as a current collector. Compared with the conventional wet slurry electrode manufacturing method, the dry manufactural procedure and infrastructure are simpler, the production cost is lower, and the process eliminates volatile organic compound emission and is more environmentally friendly, and the ability of making thick (>120µm) electrodes with high tap density results in high energy density of final energy storage device. A prototype LIBs of LiNi0.6Mn0.2Co0.2O2 (NMC622)/graphite also has 230 Wh/ kg energy density.
The feasibility of non-destructive detection and classification of in-shell insect-infested almonds was examined by using multispectral imaging (MSI) technology combined with chemometrics. Differentiation of reflectance spectral data between intact and insect-infested almonds was attempted by using analytical approaches based on principal component analysis and support vector machines, classification accuracy rates as high as 99.1% in the calibration set and 97.5% in the prediction set were achieved. Meanwhile, the in-shell almonds were categorized into three classes (intact, slightly infested and severely infested) based on the degree of damage caused by insect infestation and were characterized quantitatively by the analysis of shell/kernel weight ratio. A three-class model for the identification of intact, slightly infested and severely infested almonds yielded acceptable classification performance (95.6% accuracy in the calibration set and 93.3% in the prediction set). These results revealed that MSI technology combined with chemometrics may be a promising approach for the non-destructive detection of hidden insect damage in almonds and could be used for industrial applications.
The Wadden Sea is a unique coastal wetland containing an uninterrupted stretch of tidal flats that span a distance of nearly 500km along the North Sea coast from the Netherlands to Denmark. The development of this system is under pressure of climate change and especially the associated acceleration in sea-level rise (SLR). Sustainable management of the system to ensure safety against flooding of the hinterland, to protect the environmental value and to optimise the economic activities in the area requires predictions of the future morphological development.
The Dutch Wadden Sea has been accreting by importing sediment from the ebb-tidal deltas and the North Sea coasts of the barrier islands. The average accretion rate since 1926 has been higher than that of the local relative SLR. The large sediment imports are predominantly caused by the damming of the Zuiderzee and Lauwerszee rather than due to response to this rise in sea level. The intertidal flats in all tidal basins increased in height to compensate for SLR.
The barrier islands, the ebb-tidal deltas and the tidal basins that comprise tidal channels and flats together form a sediment-sharing system. The residual sediment transport between a tidal basin and its ebb-tidal delta through the tidal inlet is influenced by different processes and mechanisms. In the Dutch Wadden Sea, residual flow, tidal asymmetry and dispersion are dominant. The interaction between tidal channels and tidal flats is governed by both tides and waves. The height of the tidal flats is the result of the balance between sand supply by the tide and resuspension by waves.
At present, long-term modelling for evaluating the effects of accelerated SLR mainly relies on aggregated models. These models are used to evaluate the maximum rates of sediment import into the tidal basins in the Dutch Wadden Sea. These maximum rates are compared to the combined scenarios of SLR and extraction-induced subsidence, in order to explore the future state of the Dutch Wadden Sea.
For the near future, up to 2030, the effect of accelerated SLR will be limited and hardly noticeable. Over the long term, by the year 2100, the effect depends on the SLR scenarios. According to the low-end scenario, there will be hardly any effect due to SLR until 2100, whereas according to the high-end scenario the effect will be noticeable already in 2050.
Traditional antibiograms can guide empiric antibiotic therapy, but they may miss differences in resistance across patient subpopulations. In this retrospective descriptive study, we constructed and validated antibiograms using International Classification of Disease, Tenth Revision (ICD-10) codes and other discrete data elements to define a cohort of previously healthy children with urinary tract infections. Our results demonstrate increased antibiotic susceptibility. This methodology may be modified to create other syndrome-specific antibiograms.
This study aim to derive and validate a simple and well-performing risk calculator (RC) for predicting psychosis in individual patients at clinical high risk (CHR).
From the ongoing ShangHai-At-Risk-for-Psychosis (SHARP) program, 417 CHR cases were identified based on the Structured Interview for Prodromal Symptoms (SIPS), of whom 349 had at least 1-year follow-up assessment. Of these 349 cases, 83 converted to psychosis. Logistic regression was used to build a multivariate model to predict conversion. The area under the receiver operating characteristic (ROC) curve (AUC) was used to test the effectiveness of the SIPS-RC. Second, an independent sample of 100 CHR subjects was recruited based on an identical baseline and follow-up procedures to validate the performance of the SIPS-RC.
Four predictors (each based on a subset of SIPS-based items) were used to construct the SIPS-RC: (1) functional decline; (2) positive symptoms (unusual thoughts, suspiciousness); (3) negative symptoms (social anhedonia, expression of emotion, ideational richness); and (4) general symptoms (dysphoric mood). The SIPS-RC showed moderate discrimination of subsequent transition to psychosis with an AUC of 0.744 (p < 0.001). A risk estimate of 25% or higher had around 75% accuracy for predicting psychosis. The personalized risk generated by the SIPS-RC provided a solid estimate of conversion outcomes in the independent validation sample, with an AUC of 0.804 [95% confidence interval (CI) 0.662–0.951].
The SIPS-RC, which is simple and easy to use, can perform in the same manner as the NAPLS-2 RC in the Chinese clinical population. Such a tool may be used by clinicians to counsel appropriately their patients about clinical monitor v. potential treatment options.