Previous studies have demonstrated that auxin (indole‐3‐acetic acid) and nitric oxide (NO) are plant growth regulators that coordinate several plant physiological responses determining root ...architecture. Nonetheless, the way in which these factors interact to affect these growth and developmental processes is not well understood. The Arabidopsis thaliana F‐box proteins TRANSPORT INHIBITOR RESPONSE 1/AUXIN SIGNALING F‐BOX (TIR1/AFB) are auxin receptors that mediate degradation of AUXIN/INDOLE‐3‐ACETIC ACID (Aux/IAA) repressors to induce auxin‐regulated responses. A broad spectrum of NO‐mediated protein modifications are known in eukaryotic cells. Here, we provide evidence that NO donors increase auxin‐dependent gene expression while NO depletion blocks Aux/IAA protein degradation. NO also enhances TIR1‐Aux/IAA interaction as evidenced by pull‐down and two‐hybrid assays. In addition, we provide evidence for NO‐mediated modulation of auxin signaling through S‐nitrosylation of the TIR1 auxin receptor. S‐nitrosylation of cysteine is a redox‐based post‐translational modification that contributes to the complexity of the cellular proteome. We show that TIR1 C140 is a critical residue for TIR1–Aux/IAA interaction and TIR1 function. These results suggest that TIR1 S‐nitrosylation enhances TIR1–Aux/IAA interaction, facilitating Aux/IAA degradation and subsequently promoting activation of gene expression. Our findings underline the importance of NO in phytohormone signaling pathways.
This paper analyses six strategies for managing the MSW generated in Asturias (Spain) in terms of their environmental impacts applying the Life Cycle Analysis methodology. To this end, the effect of ...these strategies on Human Health, Ecosystem Quality, Global Warming and Resource Depletion is studied. The analysed management options include direct landfill with recovery of biogas (S-0), direct incineration with energy recovery (S-1), biomethanization of the source-separated organic fraction with direct incineration of the mixed fraction (S-2), biomethanization of the source-separated organic fraction, sorting of the mixed fraction and incineration of the rejected fraction (S-3), biomethanization of the source-separated organic fraction, sorting of the mixed fraction and incineration of the rejected fraction following aerobic stabilization of the organic fraction (S-4) and biomethanization of the source-separated organic fraction, sorting of the mixed fraction and landfill of the rejected following aerobic stabilization of the organic fraction (S-5). The Consortium for Waste Management (COGERSA) provide data regarding on transport and collection of waste and consumption of energy, water, oil and reagents at each processes. The results obtained suggest that Scenario S-3 has the least impact on the analysed damage categories while the scenarios including landfilling produces the greatest impact in all the categories analysed. Regarding involved processes in studied scenarios, the transport produces a significant impact in the environment, biomethanization contributes to reducing the impact in all the damage categories and incineration adversely affects the categories of Human Health and Climate Change, but helps to reduce damage in the Resources category.
•Six waste management scenarios were assessed by LCA methodology.•Four damage categories were considered, according to the Impact 2002+ method.•Waste landfilling is the option with greater environmental impacts.•Sorting and biomethanization processes provide savings in the studied categories.•Incineration helps to reduce damage in the Resources Depletion category.
Abstract Refeeding after acute pancreatitis (AP) is traditionally started in a successively increasing manner when abdominal pain is absent and pancreatic enzymes are decreasing. We aimed to evaluate ...length of hospital stay (LOHS) and refeeding tolerance for early refeeding and/or immediately full caloric intake in patients recovering from AP. Methods In this randomized, open-label trial, patients with AP were randomized into four different refeeding protocols. Group 1 and 2 received a stepwise increasing diet during three days while 3 and 4 received an immediately full caloric, low fat diet. Group 2 and 4 started refeeding early (once bowel sounds returned) and 1 and 3 started at standard time (bowel sounds present, no abdominal pain, no fever, leucocytes and pancreatic enzymes decreasing). Main outcomes measurements were LOHS and tolerance (ability to ingest >50% of meals without severe pain, nausea or AP relapse). Results Eighty patients were evaluated and 72 randomized (median age 60 years, range 24–85, 33 male). LOHS was significantly reduced after early refeeding (median 5 versus 7 days ( p = 0.001)) but not in patients receiving immediately full caloric diet, compared to standard management (6 versus 6 days ( p = 0.12)). There was no difference in refeeding tolerance comparing immediately full caloric diet versus stepwise increasing diet (31/35 (89%) versus 33/37 (89%) patients tolerating the treatment, p = 1.00) or early versus standard time for refeeding (33/37 (89%) versus 31/35 (89%), ( p = 1.00)). Conclusions Refeeding after AP when bowel sounds are present with immediately full caloric diet is safe and well tolerated. Early refeeding shortens LOHS.
Phytohormone-like acting compounds previously have been suggested to be involved in the phytostimulatory action exerted by the plant-beneficial rhizobacterium Bacillus amyloliquefaciens FZB42. ...Analyses by high-performance liquid chromatography and gas chromatography-mass spectrometry performed with culture filtrates of FZB42 demonstrated the presence of indole-3-acetic acid (IAA), corroborating it as one of the pivotal plant-growth-promoting substances produced by this bacterium. In the presence of 5 mM tryptophan, a fivefold increase in IAA secretion was registered. In addition, in the trp auxotrophic strains E101 (ΔtrpBA) and E102 (ΔtrpED), and in two other strains bearing knockout mutations in genes probably involved in IAA metabolism, E103 (ΔysnE, putative IAA transacetylase) and E105 (ΔyhcX, putative nitrilase), the concentration of IAA in the culture filtrates was diminished. Three of these mutant strains were less efficient in promoting plant growth, indicating that the Trp-dependent synthesis of auxins and plant growth promotion are functionally related in B. amyloliquefaciens.
The study of the OH adsorption process on Pt single crystals is of paramount importance since this adsorbed species is considered the main intermediate in many electrochemical reactions of interest, ...in particular, those oxidation reactions that require a source of oxygen. So far, it is frequently assumed that the OH adsorption on Pt only takes place at potentials higher than 0.55 V (versus the reversible hydrogen electrode), regardless of the Pt surface structure. However, by CO displacement experiments, alternating current voltammetry, and Raman spectroscopy, we demonstrate here that OH is adsorbed at more negative potentials on the low coordinated Pt atoms, the Pt steps. This finding opens a new door in the mechanistic study of many relevant electrochemical reactions, leading to a better understanding that, ultimately, can be essential to reach the final goal of obtaining improved catalysts for electrochemical applications of technological interest.
Helicobacter pylori is considered one of the major risk factors underlying the development of gastritis and gastric and duodenal ulcers. Moreover, 50% of the population carries this bacterium, and ...consequently, when it is detected, eradication of H. pylori is strongly recommended. Regarding the use of probiotics as functional agents, several studies have shown that there is a direct relationship between the addition of certain probiotic bacteria and in vitro inhibition of H. pylori; however, in vivo studies showing bifidobacterial activity against H. pylori remain scarce. In this study, a Bifidobacterium bifidum strain which proved active in vitro against H. pylori has been isolated, with inhibition levels reaching 81.94% in the case of the supernatant and even 94.77% inhibition for supernatant purified by cationic exchange followed by an inverse phase. In vivo studies using a BALB/c mouse model have proved that this strain partially relieves damage to gastric tissues caused by the pathogen and also decreases the H. pylori pathogenicity ratio. This novel strain fulfills the main properties required of a probiotic (resistance to gastrointestinal juices, biliary salts, NaCl, and low pH; adhesion to intestinal mucus; and sensitivity to antibiotics). Furthermore, the absence of undesirable metabolites has been demonstrated, and its food safety status has been confirmed by acute ingestion studies in mice. In summary, the results presented here demonstrate that Bifidobacterium bifidum CECT 7366 can be considered a probiotic able to inhibit H. pylori both in vitro and in vivo.
Imazethapyr, a post-emergent herbicide used in worldwide soybean and corn crops, induces genetic and biochemical alterations in aquatic vertebrates. This study examined the relationship between ...biomarkers at different organization levels and imazethapyr real-life route exposure in
Boana pulchella
adults. Frogs were exposed to imazethapyr-based formulation Pivot
®
H (10.59%) at concentrations representing possible acute routes: field runoff (S1:10 mg.L
−1
), exposure after direct foliar application (S2:100 mg.L
−1
) and during direct foliar application (S3:1000 mg.L
−1
). Post-exposure, endpoints levels were evaluated: organism alterations, biochemical activities and cytogenetic assays. Forty-eight hours post-exposure, antioxidant enzymes decrease, micronuclei induction and DNA damage were observed in all scenarios, while cholinesterase activity increase and body condition reduction were observed in frog-exposed to S3. Ninety-six hours post-exposure, frogs showed glutathione-S-transferase inhibition in S1, micronuclei induction in S2 and S3, and DNA-damage increase in S3. Herbicides routes of exposures in real-life could indicate that authorized applications have a risk to amphibian populations.
We present the largest and most homogeneous catalog of H ii regions and associations compiled so far. The catalog comprises more than 7000 ionized regions, extracted from 306 galaxies observed by the ...CALIFA survey. We describe the procedures used to detect, select, and analyze the spectroscopic properties of these ionized regions. In the current study we focus on characterizing of the radial gradient of the oxygen abundance in the ionized gas, based on the study of the deprojecteddistribution of H ii regions. We found that all galaxies without clear evidence of an interaction present a common gradient in the oxygen abundance, with a characteristic slope of αO/H = −0.1 dex/re between 0.3 and 2 disk effective radii (re), and a scatter compatible with random fluctuations around this value, when the gradient is normalized to the disk effective radius. The slope is independent of morphology, the incidence of bars, absolute magnitude, or mass. Only those galaxies with evidence of interactions and/or clear merging systems present a significantly shallower gradient, consistent with previous results. The majority of the 94 galaxies with H ii regions detected beyond two disk effective radii present a flattening in the oxygen abundance. The flattening is statistically significant. We cannot provide a conclusive answer regarding the origin of this flattening. However, our results indicate that its origin is most probably related to the secular evolution of galaxies. Finally, we find a drop/truncation of the oxygen abundance in the inner regions for 26 of the galaxies. All of them are non-interacting, mostly unbarred Sb/Sbc galaxies. This feature is associated with a central star-forming ring, which suggests that both features are produced by radial gas flows induced by resonance processes. Our result suggests that galaxy disks grow inside-out, with metal enrichment driven by the local star formation history and with a small variation galaxy-by-galaxy. At a certain galactocentric distance, the oxygen abundance seems to be correlated well with the stellar mass density and total stellar mass of the galaxies, independently of other properties of the galaxies. Other processes, such as radial mixing and inflows/outflows seem to have a limited effect on shaping of the radial distribution of oxygen abundances, although they are not ruled out.
Aims.
Star-forming galaxies with nebular He
II
emission contain very energetic ionizing sources of radiation, which can be considered as analogs to the major contributors of the reionization of the ...Universe in early epochs. It is therefore of great importance to provide a reliable absolute scale for the equivalent effective temperature (
T
*
) for these sources.
Methods.
We study a sample of local (
z
< 0.2) star-forming galaxies showing optical nebular He
II
emission using the so-called softness diagrams, involving emission lines of two elements in two consecutive stages of ionization (e.g., S
II
/S
III
vs. O
II
/O
III
). We use for the first time the He
I
/He
II
ratio in these diagrams in order to explore the higher range of
T
*
expected in these objects, and to investigate the role of possible mechanisms driving the distribution of galaxy points in these diagrams. We build grids of photoionization models covering different black-body temperatures, model cluster atmospheres, and density-bounded geometries to explain the conditions observed in the sample.
Results.
We verified that the use of the softness diagrams including the emission-line ratio He
I
/He
II
combined with black-body photoionization models can provide an absolute scale of
T
*
for these objects. The application of a Bayesian-like code indicates
T
*
in the range 50−80 kK for the sample of galaxies, with a mean value higher than 60 kK. The average of these high temperature values can only be reproduced using cluster model populations with nearly metal-free stars, although such ionizing sources cannot explain either the highest
T
*
values, beyond 1
σ
, or the dispersion observed in the softness diagrams. According to our photoionization models, most sample galaxies could be affected to some extent by ionizing photon leaking, presenting a mean photon absorption fraction of 26% or higher depending on the metallicity assumed for the ionizing cluster. The entire range of He
I
/He
II
, S
II
/S
III
, and O
II
/O
III
ratios for these HeII-emitting galaxies is reproduced with our models, combining nearly metal-free ionizing clusters and photon leaking under different density-bounded conditions.
This paper studies the problem of jointly estimating multiple network processes driven by a common unknown input, thus effectively generalizing the classical blind multi-channel identification ...problem to graphs. More precisely, we model network processes as graph filters and consider the observation of multiple graph signals corresponding to outputs of different filters defined on a common graph and driven by the same input. Assuming that the underlying graph is known and the input is unknown, our goal is to recover the specifications of the network processes, namely the coefficients of the graph filters, only relying on the observation of the outputs. Being generated by the same input, these outputs are intimately related and we leverage this relationship for our estimation purposes. Two settings are considered, one where the orders of the filters are known and another one where they are not known. For the former setting, we present a least-squares approach and provide conditions for recovery. For the latter scenario, we propose a sparse recovery algorithm with theoretical performance guarantees. Numerical experiments illustrate the effectiveness of the proposed algorithms, the influence of different parameter settings on the estimation performance, and the validity of our theoretical claims.
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