It has long been proposed that phase-separated compartments can provide a basis for the formation of cellular precursors in prebiotic environments. However, we know very little about the properties ...of coacervates formed from simple peptides, their compatibility with ribozymes or their functional significance. Here we assess the conditions under which functional ribozymes form coacervates with simple peptides. We find coacervation to be most robust when transitioning from long homopeptides to shorter, more pre-biologically plausible heteropeptides. We mechanistically show that these RNA-peptide coacervates display peptide-dependent material properties and cofactor concentrations. We find that the interspacing of cationic and neutral amino acids increases RNA mobility, and we use isothermal calorimetry to reveal sequence-dependent Mg
partitioning, two critical factors that together enable ribozyme activity. Our results establish how peptides of limited length, homogeneity and charge density facilitate the compartmentalization of active ribozymes into non-gelating, magnesium-rich coacervates, a scenario that could be applicable to cellular precursors with peptide-dependent functional phenotypes.
This article examines the potential benefits of using Data Envelopment Analysis (DEA) for conducting energy-efficiency assessment of wastewater treatment plants (WWTPs). WWTPs are characteristically ...heterogeneous (in size, technology, climate, function …) which limits the correct application of DEA. This paper proposes and describes the Robust Energy Efficiency DEA (REED) in its various stages, a systematic state-of-the-art methodology aimed at including exogenous variables in nonparametric frontier models and especially designed for WWTP operation. In particular, the methodology systematizes the modelling process by presenting an integrated framework for selecting the correct variables and appropriate models, possibly tackling the effect of exogenous factors. As a result, the application of REED improves the quality of the efficiency estimates and hence the significance of benchmarking. For the reader's convenience, this article is presented as a step-by-step guideline to guide the user in the determination of WWTPs energy efficiency from beginning to end. The application and benefits of the developed methodology are demonstrated by a case study related to the comparison of the energy efficiency of a set of 399 WWTPs operating in different countries and under heterogeneous environmental conditions.
•A methodology for carrying out robust energy efficiency quantification is developed.•The methodology is based on the Data Envelopment Analysis framework.•The methodology systematizes the large pool of open choices for the user.•The usefulness is demonstrated step-by-step on a comprehensive set of 399 WWTPs.•Controlling for exogenous factors can lead to changes of ±50% in observed efficiency.
Colistin resistance genes mcr-3 and mcr-1 have been detected in an Escherichia coli isolate from cattle faeces in a Spanish slaughterhouse in 2015. The sequences of both genes hybridised to same ...plasmid band of ca 250 kb, although colistin resistance was non-mobilisable. The isolate was producing extended-spectrum beta-lactamases and belonged to serotype O9:H10 and sequence type ST533. Here we report an mcr-3 gene detected in Europe following earlier reports from Asia and the United States.
Light and gibberellins (GAs) mediate many essential and partially overlapping plant developmental processes. DELLA proteins are GA-signalling repressors that block GA-induced development. GA induces ...degradation of DELLA proteins via the ubiquitin/proteasome pathway but light promotes accumulation of DELLA proteins by reducing GA levels. It was proposed that DELLA proteins restrain plant growth largely through their effect on gene expression. However, the precise mechanism of their function in coordinating GA signalling and gene expression remains unknown. Here we characterize a nuclear protein interaction cascade mediating transduction of GA signals to the activity regulation of a light-responsive transcription factor. In the absence of GA, nuclear-localized DELLA proteins accumulate to higher levels, interact with phytochrome-interacting factor 3 (PIF3, a bHLH-type transcription factor) and prevent PIF3 from binding to its target gene promoters and regulating gene expression, and therefore abrogate PIF3-mediated light control of hypocotyl elongation. In the presence of GA, GID1 proteins (GA receptors) elevate their direct interaction with DELLA proteins in the nucleus, trigger DELLA protein's ubiquitination and proteasome-mediated degradation, and thus release PIF3 from the negative effect of DELLA proteins.
•Effects of imidacloprid (IMI) were evaluated on Hypsiboas pulchellus tadpoles.•Mortality studies revealed a LC5096h value of 84.91mg/L of IMI.•IMI induced both micronuclei and DNA strand breaks in ...circulating blood cells.•Binucleated, blebbed, and notched cells were induced after 48 and 96h of treatment.•First evidence of deleterious effects of IMI on an Argentinean amphibian species.
Acute toxicity and genotoxicity of imidacloprid (IMI) was evaluated on Hypsiboas pulchellus (Anura: Hylidae) tadpoles exposed under laboratory conditions. A lethal effect was used as the end point for lethality, whereas the frequency of micronuclei (MNs) and DNA single-strand breaks evaluated by the single cell gel electrophoresis assay were employed as end points for genotoxicity. Experiments were performed on tadpoles at stage 36 (range, 35–37) according to the classification proposed by Gosner. Mortality studies revealed an LC50 (96h) value of 84.91mg/L IMI (95% confidence limits, 77.20–93.04). While increased frequency of MNs was observed when 15 and 30mg/L were assayed for 48h, only 15mg/L increased the frequency of MNs in tadpoles exposed for 96h. Furthermore, other nuclear abnormalities, i.e., binucleated cells and blebbed and notched nuclei, were induced in tadpoles exposed for both 48h when treated with 15mg/L and 96h when treated with 15 and 30mg/L. An increase in the genetic damage index was observed in tadpoles treated with 30mg/L for 48 and 96h. This study represents the first evidence of acute lethal and sublethal effects exerted by IMI on tadpoles of an amphibian species native to Argentina. Finally, our findings highlight the hazardous properties of this insecticide for nontarget living species exposed to this agrochemical.
•A new framework reliably quantifies and decomposes epistemic and aleatory uncertainties.•A new emulator reliably approximates the response of a stochastic building performance simulator.•The ...computational cost of quantifying uncertainties with the emulator is negligible.•Heating loads are more sensitive to insulation thickness than to occupants’ behaviours.•Cooling loads are more sensitive to occupants’ behaviours than to envelope parameters.
A good framework for the quantification and decomposition of uncertainties in dynamic building performance simulation should: (i) simulate the principle deterministic processes influencing heat flows and the stochastic perturbations to them, (ii) quantify and decompose the total uncertainty into its respective sources, and the interactions between them, and (iii) achieve this in a computationally efficient manner. In this paper we introduce a new framework which, for the first time, does just that. We present the detailed development of this framework for emulating the mean and the variance in the response of a stochastic building performance simulator (EnergyPlus co-simulated with a multi agent stochastic simulator called No-MASS), for heating and cooling load predictions. We demonstrate and evaluate the effectiveness of these emulators, applied to a monozone office building. With a range of 25–50 kWh/m2, the epistemic uncertainty due to envelope parameters dominates over aleatory uncertainty relating to occupants' interactions, which ranges from 6–8 kWh/m2, for heating loads. The converse is observed for cooling loads, which vary by just 3 kWh/m2 for envelope parameters, compared with 8–22 kWh/m2 for their aleatory counterparts. This is due to the larger stimuli provoking occupants' interactions. Sensitivity indices corroborate this result, with wall insulation thickness (0.97) and occupants' behaviours (0.83) having the highest impacts on heating and cooling load predictions respectively. This new emulator framework (including training and subsequent deployment) achieves a factor of c.30 reduction in the total computational budget, whilst overwhelmingly maintaining predictions within a 95% confidence interval, and successfully decomposing prediction uncertainties.
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 a simple methodology to design a pretargeted drug delivery system, based on clickable anti-programmed death ligand 1 (anti-PD-L1) antibodies (Abs) and clickable bovine serum albumin (BSA) ...nanoparticles (NPs). Pretargeted drug delivery is based on the decoupling of a targeting moiety and a drug-delivering vector which can then react in vivo after separate injections. This may be key to achieve active targeting of drug-delivering NPs toward cancerous tissue. In pretargeted approaches, drug-delivering NPs were observed to accumulate in a higher amount in the targeted tissue due to shielding-related enhanced blood circulation and size-related enhanced tissue penetration. In this work, BSA NPs were produced using the solvent precipitation methodology that renders colloidally stable NPs, which were subsequently functionalized with a clickable moiety based on chlorosydnone (Cl-Syd). Those reactive groups are able to specifically react with dibenzocyclooctyne (DBCO) groups in a click-type fashion, reaching second-order reaction rate constants as high as 1.9 M
·s
, which makes this reaction highly suitable for in vivo applications. The presence of reactive Cl-Syd was demonstrated by reacting the functionalized NPs with a DBCO-modified sulfo-cyanine-5 dye. With this reaction, it was possible to infer the number of reactive moieties per NPs. Finally, and with the aim of demonstrating the suitability of this system to be used in pretargeted strategies, functionalized fluorescent NPs were used to label H358 cells with a clickable anti-PD-L1 Ab, applying the reaction between Cl-Syd and DBCO as corresponding clickable groups. The results of these experiments demonstrate the bio-orthogonality of the system to perform the reaction in vitro, in a period as short as 15 min.
This work describes an advanced model for the analysis of contact forces and deformations in spur gear transmissions. The deformation at each gear contact point is formulated as a combination of a ...global and a local term. The former is obtained by means of a finite element model and the latter is described by an analytical approach which is derived from Hertzian contact theory. Then the compatibility and complementary conditions are imposed, leading to a nonlinear system of equations subjected to inequality restrictions that should be solved once the position of each gear centre is known. A numerical example is presented where the quasi-static behaviour of a single stage spur gear transmission is discussed, showing the capabilities of the methodology to obtain the Loaded Transmission Error under several load levels as well as some other related measures such as load ratio or meshing stiffness.
► A model for study contact forces and deformations in external spur gear transmissions. ► Local and global deformation considered separately, reducing computational effort. ► Transmitted torque, friction and working distance affects LTE, meshing stiffness and Load Ratio. ► Meshing stiffness in double contact period is calculated considering the coupled deflection of adjacent contacting pairs. ► Gear body deflection has a great influence on the values of the meshing stiffness.
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