Silage is a widespread practice to preserve forage. Poor storage conditions can lead to mold contamination and mycotoxin production. The aim of this study was to establish the occurrence of toxigenic ...fungal species and to determine aflatoxins (AFs), ochratoxin A (OTA), fumonisin B1 (FB1) and deoxinivalenol (DON) in corn silage intended for bovines before and after fermentation in farms located in São Paulo and Rio de Janeiro States, Brazil. Fungal counts were done by surface-spread method. Toxigenic ability of isolates was evaluated in vitro. AFs natural contamination was determined by TLC and HPLC. Total fungal counts were generally high. Aspergillus flavus, Penicillium citrinum, and Fusarium verticillioides were the prevalent species. Toxigenic strains were isolated. Aflatoxin levels differed (P < 0.0001) from 2 to 45 μg g−1 and from 2 to 100 μg g−1 in pre and post-fermentation samples, respectively. Ochratoxin A, FB1 and DON levels found in pre-fermentation samples were higher than in post-fermentation (P < 0.0001). Mycotoxins and toxigenic fungi were present before and after fermentation in corn silage intended for bovines in Brazil. Aflatoxin B1 (AFB1) increased during storage whereas OTA, FB1 and DON decreased. Determination of mycotoxin levels and their occurrence in corn silage are important to provide information so that the assessments of risk for animal feed and livestock environment could be made.
► Corn silage mycotoxicology in tropical climates has not been previously described. ► The occurrence of the main toxigenic fungal species was determined. ► Mycotoxins before and after silage fermentation were quantified. ► Fungi and mycotoxins contamination monitoring could prevent animal risk exposure.
We propose a new methodology for leveraging deep generative priors for Bayesian inference in imaging inverse problems. Modern Bayesian imaging often relies on score-based diffusion generative priors, ...which deliver remarkable point estimates but significantly underestimate uncertainty. Push-forward models such as variational auto-encoders and generative adversarial networks provide a robust alternative, leading to Bayesian models that are provably well-posed and which produce accurate uncertainty quantification results for small problems. However, push-forward models scale poorly to large problems because of issues related to bias, mode collapse and multimodality. We propose to address this difficulty by embedding a conditional deep generative prior within an empirical Bayesian framework. We consider generative priors with a super-resolution architecture, and perform inference by using a Bayesian computation strategy that simultaneously computes the maximum marginal likelihood estimate (MMLE) of the low-resolution image of interest, and draws Monte Carlo samples from the posterior distribution of the high-resolution image, conditionally to the observed data and the MMLE. The methodology is demonstrated with an image deblurring experiment and comparisons with the state-of-the-art.
To evaluate the mycobiota and natural levels of aflatoxins, fumonisins and zearalenone present in compound feed and home-corn grains intended for fattening pigs. Total fungi, Fusarium and Aspergillus ...species occurrence were examined. Aflatoxins and zearalenone were detected by thin-layer chromatography and fumonisins by high-pressure liquid chromatography. Fungal counts were generally higher than 1 x 10⁵ colony forming units (CFU) ml⁻¹. Aspergillus flavus, Aspergillus parasiticus and Fusarium verticillioides were the most prevalent species. FB₁ and FB₂ were detected in all feed and corn samples. Aflatoxin B₁ was detected in 33·33% of initial and growing feed and in 44·44% of final feed samples. It was not detected in corn samples. All feed and corn samples were negative for AFB₂, AFG₁, AFG₂ and ZEA presence during all growing stages tested. Fungal counts at all growing periods exceeded the levels proposed as feed hygienic quality limits. Aflatoxin levels in all feeds and fumonisin levels in many samples were higher than the established regulations. The presence of mycotoxins indicates the existence of contamination. This fact requires periodic monitoring to prevent the occurrence of mycotoxicosis in animal production, to reduce the economic losses and to minimize hazards to human health.
Biotrickling filters (BTF) have been applied to treat waste air. Controlling the water content (WC) of BTFs is fundamental to ensure an adequate interfacial mass transfer and the support of the ...biofilm activity. A sensor system based on electrical conductance measurement was developed for the online assessment of the WC in a bench scale polyurethane foam (PUF) packed bed. ON/OFF and rule-based control algorithms were applied to keep the water content in a biofilm-free PUF-packed bed within the optimal range of 70–90% through the activation of a hydraulic pump. The applied control algorithms activated the pump at various times, which yielded different energy and water savings even under similar WC conditions suitable for biotrickling filtration of waste air. It was estimated that using the ON/OFF and rule-based system control schemes reduced the electrical power consumption by 98% and 99.8%, respectively, compared to systems under continuous water irrigation.
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•Electrical conductance sensors were developed for online WC assessment.•Control system algorithms reduced up to 98% the irrigation energy consumption.•Control system algorithms kept optimal WC in a polyurethane packed bed.•Rule-based system control kept homogeneous WC along polyurethane packed bed.
Invasive alien plant species (IAPS) are severely changing ecosystems on earth. Studying the interactions that allow IAPS to establish and spread in the new regions is crucial. Ants can disperse ...exotic fleshy fruits. We asked the following questions at three different sites of Chaco Mountain Forest (Córdoba, Argentina): (1) Do ants disperse diaspores of native, neonative and IAPS differentially? (2) Which is the ant species assemblage and their role in the secondary dispersal of each of the selected plant species? (3) Do ants interact in different ways with intact and manipulated fruits, and these interactions vary within plant species origin? and (4) Are diaspore traits different among the plant species considered? We selected four plant species:
Celtis ehrenbergiana
(native),
Lantana camara
(neonative),
Pyracantha angustifolia
and
Ligustrum lucidum
(IAPS). Two experiments were performed: (1) To disentangle the contribution of ants to the secondary dispersal process, and (2) To investigate the ant behavior of ground-foraging ant species when they encountered the fruits. Additionally, we measured fruit mass and the number of seeds per fruit. Ants were the main diaspore dispersers on the Chaco Mountain Forest ground. Twelve ant species interacted with the fruits; the native presented the higher number, followed by the neonative, and the two IAPS. Only
Acromyrmex crassispinus
and
Pheidole cordyceps
removed diaspores. Furthermore, the fruits differed in their mass and also in the number of seeds. Our results highlight the importance of ants and also diaspores traits in these diffuse mutualisms, and enhance their role in plant-invasive processes in subtropical ecosystems.
ABSTRACT
Until recently, mass-mapping techniques for weak gravitational lensing convergence reconstruction have lacked a principled statistical framework upon which to quantify reconstruction ...uncertainties, without making strong assumptions of Gaussianity. In previous work, we presented a sparse hierarchical Bayesian formalism for convergence reconstruction that addresses this shortcoming. Here, we draw on the concept of local credible intervals (cf. Bayesian error bars) as an extension of the uncertainty quantification techniques previously detailed. These uncertainty quantification techniques are benchmarked against those recovered via Px-MALA – a state-of-the-art proximal Markov chain Monte Carlo (MCMC) algorithm. We find that, typically, our recovered uncertainties are everywhere conservative (never underestimate the uncertainty, yet the approximation error is bounded above), of similar magnitude and highly correlated with those recovered via Px-MALA. Moreover, we demonstrate an increase in computational efficiency of $\mathcal {O}(10^6)$ when using our sparse Bayesian approach over MCMC techniques. This computational saving is critical for the application of Bayesian uncertainty quantification to large-scale stage IV surveys such as LSST and Euclid.
ABSTRACT
We present optical follow-up observations with the Deca-Degree Optical Transient Imager (DDOTI) telescope of gravitational-wave (GW) events detected during the Advanced LIGO and Advanced ...Virgo O3 observing run. DDOTI is capable of responding to an alert in a few minutes, has an instantaneous field of about 69 deg2, and obtains 10σ upper limits of wlim = 18.5–20.5 AB mag in 1000 s of exposure, depending on the conditions. We observed 54 per cent (26 out of 48) of the unretracted GW alerts and did not find any electromagnetic counterparts. We compare our upper limits to various possible counterparts: the kilonova AT 2017gfo, models of radioactive- and magnetar-powered kilonovae, short gamma-ray burst afterglows, and active galactic nucleus (AGN) flares. Although the large positional uncertainties of GW sources do not allow us to place strong constraints during O3, DDOTI observations of well-localized GW events in O4 and beyond could meaningfully constrain models of compact binary mergers. We show that DDOTI is able to detect kilonovae similar to AT 2017gfo up to about 200 Mpc and magnetar-powered kilonovae up to 1 Gpc. We calculate that nearby (≲200 Mpc) afterglows have a high chance (≈70 per cent) to be detected by rapid (≲3 h) DDOTI observations if observed on-axis, whereas off-axis afterglows are unlikely to be seen. Finally, we suggest that long-term monitoring of massive BBH events with DDOTI could confirm or rule out late AGN flares associated with these events.
Aim: To determine fungal genera, Aspergillus and Fusarium species and aflatoxin B1 (AFB1), zearalenone (ZEA), deoxynivalenol (DON), fumonisin B1 (FB1) contamination from pre‐ and postfermented corn ...silage produced in the most important region of Argentina where silage practice is developed.
Methods and Results: Sampling of corn silos was performed manually through silos in transects at three levels: upper, middle and low sections. AFB1 and FB1 were quantified by high‐performance liquid chromatography, zearalenone by enzyme‐linked immunosorbent assay and DON by gas chromatography. Over 90% of the samples showed counts higher than 1 × 104 CFU g−1. Aspergillus flavus and Fusarium verticillioides were the prevalent species. Some tested samples were contaminated with AFB1, ZEA, DON and FB1.
Conclusions: This study demonstrates the presence of fungi and AFB1, ZEA, DON and FB1 contamination in corn silage in Argentina.
Significance and Impact of the Study: This manuscript makes a contribution to the knowledge of mycotoxins in Argentinean silage in particular because the environmental conditions in this country differ from those of most reports. The comparison of pre‐ and postfermentation silage is also outstanding. Therefore, information on fungi and mycotoxins present in silage – an increasingly popular commodity – is useful to estimate potential risk for animal and human health.
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