This paper addresses the problem of jointly estimating the statistical distribution and segmenting lesions in multiple-tissue high-frequency skin ultrasound images. The distribution of ...multiple-tissue images is modeled as a spatially coherent finite mixture of heavy-tailed Rayleigh distributions. Spatial coherence inherent to biological tissues is modeled by enforcing local dependence between the mixture components. An original Bayesian algorithm combined with a Markov chain Monte Carlo method is then proposed to jointly estimate the mixture parameters and a label-vector associating each voxel to a tissue. More precisely, a hybrid Metropolis-within-Gibbs sampler is used to draw samples that are asymptotically distributed according to the posterior distribution of the Bayesian model. The Bayesian estimators of the model parameters are then computed from the generated samples. Simulation results are conducted on synthetic data to illustrate the performance of the proposed estimation strategy. The method is then successfully applied to the segmentation of in vivo skin tumors in high-frequency 2-D and 3-D ultrasound images.
Increased soybean (Glycine max L. Merril) seed costs have motivated interest in reduced seeding rates to improve profitability while maintaining or increasing yield. However, little is known about ...the effect of early-season plant-to-plant spatial uniformity on the yield of modern soybean varieties planted at reduced seeding rates. The objectives of this study were to (i) investigate traditional and devise new metrics for characterizing early-season plant-to-plant spatial uniformity, (ii) identify the best metrics correlating plant-to-plant spatial uniformity and soybean yield, and (iii) evaluate those metrics at different seeding rate (and achieved plant density) levels and yield environments. Soybean trials planted in 2019 and 2020 compared seeding rates of 160, 215, 270, and 321 thousand seeds ha
planted with two different planters, Max Emerge and Exact Emerge, in rainfed and irrigated conditions in the United States (US). In addition, trials comparing seeding rates of 100, 230, 360, and 550 thousand seeds ha
were conducted in Argentina (Arg) in 2019 and 2020. Achieved plant density, grain yield, and early-season plant-to-plant spacing (and calculated metrics) were measured in all trials. All site-years were separated into low- (2.7 Mg ha
), medium- (3 Mg ha
), and high- (4.3 Mg ha
) yielding environments, and the tested seeding rates were separated into low (< 200 seeds m
), medium (200-300 seeds m
), and high (> 300 seeds m
) levels. Out of the 13 metrics of spatial uniformity, standard deviation (sd) of spacing and of achieved versus targeted evenness index (herein termed as ATEI, observed to theoretical ratio of plant spacing) showed the greatest correlation with soybean yield in US trials (R
= 0.26 and 0.32, respectively). However, only the ATEI sd, with increases denoting less uniform spacing, exhibited a consistent relationship with yield in both US and Arg trials. The effect of spatial uniformity (ATEI sd) on soybean yield differed by yield environment. Increases in ATEI sd (values > 1) negatively impacted soybean yields in both low- and medium-yield environments, and in achieved plant densities below 200 thousand plants ha
. High-yielding environments were unaffected by variations in spatial uniformity and plant density levels. Our study provides new insights into the effect of early-season plant-to-plant spatial uniformity on soybean yields, as influenced by yield environments and reduced plant densities.
AIMS: To acquire data on the safety‐in‐use of the probiotic Saccharomyces cerevisiae RC016 and test its ability to reduce genotoxicity caused by dietary aflatoxins (AFs). METHODS AND RESULTS: The ...probiotic was orally administered to Wistar rats. Six groups (n = 6) were arranged: feed and probiotic controls, two levels of AFs‐contaminated feed and two treatments including both the probiotic and the toxin. Genotoxiciy and cytotoxicity were evaluated with the bone marrow micronuclei assay and the comet assay and internal organs were macroscopically and microscopically examined. The tested S. cerevisiae strain did not cause genotoxicity or cytotoxicity in vivo, and it was able to attenuate AFs‐caused genotoxicity. Saccharomyces cerevisiae RC016 did not cause any impairment on the rats' health and it showed no negative impact on the weight gain. Moreover, RC016 improved zootechnical parameters in AFs‐treated animals. The beneficial effects were likely to be caused by adsorption of AFs to the yeast cell wall in the intestine and the consequent reduction in the toxin's bioavailability. CONCLUSIONS: The dietary administration of RC016 does not induce genotoxicity or cytotoxicity to rats. SIGNIFICANCE AND IMPACT OF THE STUDY: Incorporation of RC016 in the formulation of feed additives increases animal productivity. Similar effects may even occur in human food applications.
Mycotoxin contamination of animal feeds represents a hazard to human and animal health due to potential transmission to meat and milk. Barley by-products are alternative feeding supplies for animal ...production. The aims of this assay were to study the mycobiota of feedstuffs and finished swine feed, to determine the ability of
Aspergillus and
Penicillium isolates to produce ochratoxin A (OTA) and to evaluate OTA occurrence in these substrates. Corn, brewers' grains and finished swine feed samples were collected from different factories. Fungal counts were higher than 2.8
×
10
4
CFU
g
−1.
Fusarium,
Aspergillus and
Penicillium genera were isolated at high levels. A 23.7% of the isolates produced 9–116
μg
kg
−1 of OTA
in vitro. Corn samples (44%) were contaminated with 42–224
μg
kg
−1 of OTA. Finished feed (31%) and brewers' grains samples (13%) were contaminated with 36–120
μg
kg
−1 and 28–139
μg
kg
−1 of OTA, respectively. This is the first scientific report on contamination by OTA-producer molds and OTA in swine feedstuffs from Brazil. The presence of OTA in raw materials and finished feed requires periodic monitoring to prevent mycotoxicoses in animal production, reduce economic losses and minimize hazards to human health.
ABSTRACT
GRB 210704A is a burst of intermediate duration (T90 ∼ 1–4 s) followed by a fading afterglow and an optical excess that peaked about 7 d after the explosion. Its properties, and in ...particular those of the excess, do not easily fit into the well-established classification scheme of gamma-ray bursts (GRBs) as being long or short, leaving the nature of its progenitor uncertain. We present multiwavelength observations of the GRB and its counterpart, observed up to 160 d after the burst. In order to decipher the nature of the progenitor system, we present a detailed analysis of the GRB high-energy properties (duration, spectral lag, and Amati correlation), its environment, and late-time optical excess. We discuss three possible scenarios: a neutron star merger, a collapsing massive star, and an atypical explosion possibly hosted in a cluster of galaxies. We find that traditional kilonova and supernova models do not match well the properties of the optical excess, leaving us with the intriguing suggestion that this event was an exotic high-energy merger.
ABSTRACT
We report on our observing campaign of the compact binary merger GW190814, detected by the Advanced LIGO and Advanced Virgo detectors on 2019 August 14. This signal has the best localization ...of any observed gravitational wave (GW) source, with a 90 per cent probability area of 18.5 deg2, and an estimated distance of ≈240 Mpc. We obtained wide-field observations with the Deca-Degree Optical Transient Imager (DDOTI) covering 88 per cent of the probability area down to a limiting magnitude of w = 19.9 AB. Nearby galaxies within the high probability region were targeted with the Lowell Discovery Telescope (LDT), whereas promising candidate counterparts were characterized through multicolour photometry with the Reionization and Transients InfraRed (RATIR) and spectroscopy with the Gran Telescopio de Canarias (GTC). We use our optical and near-infrared limits in conjunction with the upper limits obtained by the community to constrain the possible electromagnetic counterparts associated with the merger. A gamma-ray burst seen along its jet’s axis is disfavoured by the multiwavelength data set, whereas the presence of a burst seen at larger viewing angles is not well constrained. Although our observations are not sensitive to a kilonova similar to AT2017gfo, we can rule out high-mass (>0.1 M⊙) fast-moving (mean velocity ≥0.3c) wind ejecta for a possible kilonova associated with this merger.
Abstract
We report the results of our follow-up campaign for the neutron-star—black-hole (NSBH) merger GW200115 detected during the O3 run of the Advanced LIGO and Advanced Virgo detectors. We ...obtained wide-field observations with the Deca-Degree Optical Transient Imager covering ∼20% of the total probability area down to a limiting magnitude of
w
= 20.5 AB at ∼23 hr after the merger. Our search for counterparts returns a single candidate (AT2020aeo), likely not associated with the merger. In total, only 25 sources of interest were identified by the community and later discarded as unrelated to the GW event. We compare our upper limits with the emission predicted by state-of-the-art kilonova simulations and disfavor high-mass ejecta (>0.1
M
⊙
), indicating that the spin of the system is not particularly high. By combining our optical limits with gamma-ray constraints from Swift and Fermi, we disfavor the presence of a standard short-duration burst for viewing angles ≲15° from the jet axis. Our conclusions are, however, limited by the large localization region of this GW event, and accurate prompt positions remain crucial to improving the efficiency of follow-up efforts.
Membrane overexpression of the receptor tyrosine kinase ErbB-2 (MErbB-2) accounts for a clinically aggressive breast cancer (BC) subtype (ErbB-2-positive) with increased incidence of metastases. We ...and others demonstrated that nuclear ErbB-2 (NErbB-2) also plays a key role in BC and is a poor prognostic factor in ErbB-2-positive tumors. The signal transducer and activator of transcription 3 (Stat3), another player in BC, has been recognized as a downstream mediator of MErbB-2 action in BC metastasis. Here, we revealed an unanticipated novel direction of the ErbB-2 and Stat3 interaction underlying BC metastasis. We found that Stat3 binds to its response elements (GAS) at the ErbB-2 promoter to upregulate ErbB-2 transcription in metastatic, ErbB-2-positive BC. We validated these results in several BC subtypes displaying metastatic and non-metastatic ability, highlighting Stat3 general role as upstream regulator of ErbB-2 expression in BC. Moreover, we showed that Stat3 co-opts NErbB-2 function by recruiting ErbB-2 as its coactivator at the GAS sites in the promoter of microRNA-21 (miR-21), a metastasis-promoting microRNA (miRNA). Using an ErbB-2 nuclear localization domain mutant and a constitutively activated ErbB-2 variant, we found that NErbB-2 role as a Stat3 coactivator and also its direct role as transcription factor upregulate miR-21 in BC. This reveals a novel function of NErbB-2 as a regulator of miRNAs expression. Increased levels of miR-21, in turn, downregulate the expression of the metastasis-suppressor protein programmed cell death 4 (PDCD4), a validated miR-21 target. Using an in vivo model of metastatic ErbB-2-postive BC, in which we silenced Stat3 and reconstituted ErbB-2 or miR-21 expression, we showed that both are downstream mediators of Stat3-driven metastasis. Supporting the clinical relevance of our results, we found an inverse correlation between ErbB-2/Stat3 nuclear co-expression and PDCD4 expression in ErbB-2-positive primary invasive BCs. Our findings identify Stat3 and NErbB-2 as novel therapeutic targets to inhibit ErbB-2-positive BC metastasis.
► Azospirillum improves water status in wheat seedlings under osmotic stress. ► Wider xylem vessels in coleoptiles of Azospirillum-inoculated osmotic stressed wheat seedlings. ► More efficient water ...transport in Azospirillum-inoculated osmotic stressed seedlings.
Water stress can have major impacts on plant growth and development. Although it has been demonstrated that Azospirillum brasilense Sp245 improved growth and water status in wheat seedlings under salt and osmotic stresses, knowledge of the effects the bacteria could elicit in plant shoot morphology is still scarce. The aim of this work was to examine the average vessel area and the water potential of coleoptiles from seedlings inoculated with A. brasilense Sp245 and non-inoculated controls growing either in water or in osmotic stress conditions. Changes in vessel size have an important role in the adaptation to unfavourable environmental conditions. We found that coleoptiles of Azospirillum-inoculated seedlings showed wider xylem vessels and less negative water potential when grown in 20% PEG 8000. We concluded that Azospirillum inoculation induced wider xylem vessels that might imply an enhanced coleoptile hydraulic conductance which in turn could explain the better water status observed.
Abstract These proceedings present the written contributions of the participants of the Seventh International Meeting for Researchers in Materials and Plasma Technology (7th IMRMPT), which was held ...from 7 to June 9, 2023, at the Cartagena de Indias City, Colombia, organized by the Foundation Of Researchers In Science and Technology Of Materials (FORISTOM); this was the 7th version of biennial meetings that began in 2011. The Journal of Physics: Conference Series (JPCS) proceedings volume consists of 10 contributions that were presented as talks at the conference; the abstracts of all participants’ contributions were published in the Abstract Book with ISSN 2422-3824. The conference website is available at https://foristom.org/7imrmpt/. The scientific program of the 7th IMRMPT consisted of 8 Keynote Lectures and 121 Oral Presentations, with the participation of undergraduate and graduate students, professors, researchers, and entrepreneurs from Colombia, Spain, the United States of America, Mexico, Uruguay, Brazil, among others. Moreover, the objective of IMRMPT is to bring together national and international researchers to strengthen the Materials Science, Engineering, and Nanotechnology Researchers’ Network of scientific cooperation with a global impact to promote the exchange of creative ideas, and the effective transfer of scientific knowledge, from basic research to developing technology or innovation, applied to academic, industrial, energetic, environments, and social solutions to improve our different life forms. All papers in these Proceedings refer to one of the following topics covered in the 7th IMRMPT: New Materials, Structural Integrity, Renewable Energy, Biomedical Coatings, Additive Manufacturing, Online Process Control, Non-Destructive Evaluation, Characterization of Materials, Thin Films and Nanomaterials, Wear and Corrosion/Oxidation, Plasma Applications and Technologies, Modeling, Simulation, and Diagnostics, Education in Materials Science, Engineering, and Technology, Science, Engineering, Technology, and Innovation for Social Inclusion, Surface Modification (Ion Implantation, Ion Nitriding, Magnetron Sputtering, Cathodic Arc, Sol-Gel, Thermal Spray). On behalf of the organizing committee of the 7th IMRMPT, we are incredibly thankful to all authors and participants for providing their valuable contributions to these Proceedings and the reviewers for their constructive recommendations and criticism, aiding in improving the presented articles. Besides, we especially appreciate the excellent support provided by the sponsors and partners for making this new version of the international meeting of researchers possible, allowing us to continue with the dream of strengthening and contributing to research, technological development, and innovation in the present and future of Colombia. On the other hand, it is essential to note that the event organized by the FORISTOM foundation significantly contributes to the national and international scientific community, achieving the universal interaction of the different research groups of Colombia’s academia and business sectors with other countries. Finally, the editor hopes that those interested around Materials and Plasma for Science, Engineering, and Technology can enjoy this reading, of the volume of the JPCS, which reflects a wide variety of current issues. List of Organizing Committee, National Scientific Committee, International Scientific Committee, Invited Speakers, Sponsor, Partners are available in this Pdf.
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