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The fine and hyperfine resolved state-to-state rate coefficients for the rotational (de)excitation of C3N by collision with helium are computed. To this aim a 2D potential energy surface is calculated for this system. The recoupling method is used to obtain the fine and hyperfine structure resolved rate coefficients from spin-free close-coupling calculations. These results are compared with those given by the infinite-order sudden approximation and the M-randomizing limit. General propensity rules for the transitions are also found and analysed.

12 páginas.- 4 figuras.-. 8 tablas.- 79 referencias.- Supplementary data to this article can be found online at https://doi.org/10.1016/j.jenvman.2021.112512, Polycyclic Aromatic Hydrocarbons (PAHs) are major toxic and recalcitrant pollutants in the environment. This study assessed the capacity of an isolated soil microbial consortium (OMC) to biodegrade PAHs. OMC was able to reach 100% biodegradation of naphthalene, acenaphthylene, acenaphthene, fluorene and phenanthrene in solution, and up to 76% and 50% of anthracene and fluoranthene, respectively, from a mix of 16 PAHs. To measure phenanthrene (PHE) mineralization, OMC and eight strains isolated from OMC were used and identified by PCR amplification of the gene 16S ribosomal RNA. A novel Stenotrophomonas maltophilia CPHE1, not previously described as a PAH degrader, was able to mineralize almost 40% PHE and biodegrade 90.5% in solution, in comparison to OMC that reached 100% PHE degradation, but only 18.8% mineralization. Based on metabolites identified during PHE degradation and on the detection of two genes (PAH RHDα and nahAc) in OMC consortium, two possible via were described for its degradation, through salicylic and phthalic acid. PAH RHDα, which codified the first step on PHE biodegradation pathway, was also found in the DNA of S. maltophilia CPHE1. An ecotoxicology study showed that PHE bioremediation after inoculating S. maltophilia CPHE1 for 30 days decreased by half the solution toxicity. © 2021 Elsevier Ltd, This work was supported by the Spanish Ministry of Economy and Competitiveness under the research project CMT2017-82472-C2-1-R ( AEI / FEDER ,UE). Alba, Lara-Moreno acknowledges the Spanish Ministry of Education, Culture and Sports for her FPU fellowship ( FPU15/03740 ).

8 páginas.-- 5 figuras.-- 4 tablas.-- 52 referencias.-- Supplementary data related to this article can be found at https://doi.org/10.1016/j.chemosphere.2017.10.172, The phenylurea herbicide diuron is persistent in soil, water and groundwater and is considered to be a highly toxic molecule. The principal product of its biodegradation, 3,4-dichloroaniline, exhibits greater toxicity than diuron and is persistent in the environment. Five diuron degrading microbial consortia (C1[sbnd]C5), isolated from different agricultural soils, were investigated for diuron mineralization activity. The C2 consortium was able to mineralize 81.6% of the diuron in solution, while consortium C3 was only able to mineralize 22.9%. Isolated consortia were also tested in soil slurries and in all cases, except consortium C4, DT50 (the time required for the diuron concentration to decline to half of its initial value) was drastically reduced, from 700 days (non-inoculated control) to 546, 351, and 171 days for the consortia C5, C2, and C1, respectively. In order to test the effectiveness of the isolated consortium C1 in a more realistic scenario, soil diuron mineralization assays were performed under static conditions (40% of the soil water-holding capacity). A significant enhancement of diuron mineralization was observed after C1 inoculation, with 23.2% of the herbicide being mineralized in comparison to 13.1% for the control experiment. Hydroxypropyl-β-cyclodextrin, a biodegradable organic enhancer of pollutant bioavailability, used in combination with C1 bioaugmentation in static conditions, resulted in a significant decrease in the DT50 (214 days; 881 days, control experiment). To the best of our knowledge, this is the first report of the use of soil-isolated microbial consortia in combination with cyclodextrins proposed as a bioremediation technique for pesticide contaminated soils, This work was supported by the Spanish Ministry of Economy and Competitiveness (co-funded by the Fondo Europeo de Desarrollo Regional, FEDER), under the research project CTM 2013-42599-R and Junta de Andalucía Proyect RNM 894

16 páginas.- 5 graficas.- 6 tablas.- 91 referencias.- The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fmicb.2019.02588/full#supplementary-material, A PAHs-contaminated industrial soil was analyzed using PCR amplification of the gene 16S ribosomal RNA for the detection and identification of different isolated bacterial strains potentially capable of degrading PAHs. Novel degrader strains were isolated and identified as Achromobacter xylosoxidans 2BC8 and Stenotrophomonas maltophilia JR62, which were able to degrade PYR in solution, achieving a mineralization rate of about 1% day–1. A. xylosoxidans was also able to mineralize PYR in slurry systems using three selected soils, and the total extent of mineralization (once a plateau was reached) increased 4.5, 21, and 57.5% for soils LT, TM and CR, respectively, regarding the mineralization observed in the absence of the bacterial degrader. Soil TM contaminated with PYR was aged for 80 days and total extent of mineralization was reduced (from 46 to 35% after 180 days), and the acclimation period increased (from 49 to 79 days). Hydroxypropyl-ß-cyclodextrin (HPBCD) was used as a bioavailability enhancer of PYR in this aged soil, provoking a significant decrease in the acclimation period (from 79 to 54 days) due to an increase in PYR bioavailable fraction just from the beginning of the assay. However, a similar global extension of mineralization was obtained. A. xylosoxidans was then added together with HPBCD to this aged TM soil contaminated with PYR, and the total extent of mineralization decreased to 25% after 180 days, possibly due to the competitive effect of endogenous microbiota and the higher concentration of PYR in the soil solution provoked by the addition of HPBCD, which could have a toxic effect on the A. xylosoxidans strain. © Copyright © 2019 Villaverde, Láiz, Lara-Moreno, González-Pimentel and Morillo., This work was supported by the Spanish Ministry of Economy and Competitiveness under the research project CTM2O13-42599-R (AEI/FEDER, UE) and Junta de Andalucía Proyect RNM 894. AL-M acknowledges the Spanish Ministry of Education. Culture and Sports for her FPU fellowship (FPU15/03740).

A molecular dynamics deposition model has been used to simulate the growth of rare gas matrices doped with atoms of the group 12 elements zinc, cadmium and mercury. This study investigates the sites occupied by Zn, Cd and Hg metal atoms when isolated in the solid rare gases. To probe the results, the resonance 1 P 1 ← 1 S 0 transitions of the matrix-isolated metal atoms were calculated and compared with the recorded spectra of the M/RG solids. The theoretical spectroscopy obtained in this work was generated using the molecular dynamics with quantum transitions method. In Ne matrices the metal atoms preferably occupy tetra- and hexa-vacancy sites while in the case of Xe matrices, only the single vacancy site is formed. For Ar and Kr matrices Zn but especially Cd can be trapped in tetra- and hexa-vacancy sites in addition to single-vacancy sites, while Hg atoms show exclusive occupancy in single vacancy sites.A molecular dynamics deposition model has been used to simulate the growth of rare gas matrices doped with atoms of the group 12 elements zinc, cadmium and mercury. This study investigates the sites occupied by Zn, Cd and Hg metal atoms when isolated in the solid rare gases. To probe the results, the resonance 1 P 1 ← 1 S 0 transitions of the matrix-isolated metal atoms were calculated and compared with the recorded spectra of the M/RG solids. The theoretical spectroscopy obtained in this work was generated using the molecular dynamics with quantum transitions method. In Ne matrices the metal atoms preferably occupy tetra- and hexa-vacancy sites while in the case of Xe matrices, only the single vacancy site is formed. For Ar and Kr matrices Zn but especially Cd can be trapped in tetra- and hexa-vacancy sites in addition to single-vacancy sites, while Hg atoms show exclusive occupancy in single vacancy sites.

A deposition model to simulate the growth of doped rare gas crystals is used. The study involves organic molecules with a single intramolecular hydrogen bond such as malonaldehyde, 2chloromalonaldehyde and acetylacetone as impurities. Different trapping sites were obtained depending on the rare gas properties for a given impurity, and depending on the molecular size and shape for a given crystal. Simulations were carried out by using classical molecular dynamics methods including an anharmonic thermal correction, to take into account the zero point movement of the crystal. The results are correlated to spectroscopic data previously achieved for these systems by steady state IR spectroscopy. Для імітації росту допованих кристалів інертного газу використана модель осадження. В якості домішок розглянуто органічні молекули з одним внутрішньомолекулярним водневим зв'язком: малональдегід, 2-хлормалональдегід та ацетилацетон. Залежно від властивостей кристала інертного газу, а також розмірів й форм молекул домішок отримано характеристики різних «пасток». Моделювання проводилося з використанням методів класичної молекулярної динаміки, включаючи ангармонічне наближення, з урахуванням нульових коливань кристала. Результати корелюють з отриманими раніше для цих систем даними ІЧ-спектроскопії. Для имитации роста допированных кристаллов инертного газа использована модель осаждения. В качестве примесей рассмотрены органические молекулы с одной внутримолекулярной водородной связью: малональдегид, 2-хлормалональдегид и ацетилацетон. В зависимости от свойств кристалла инертного газа, а также размеров и форм молекул примесей получены характеристики различных «ловушек». Моделирование проводилось с использованием методов классической молекулярной динамики, включая ангармоническое приближение, с учетом нулевых колебаний кристалла. Результаты коррелируют с полученными ранее для этих систем данными ИК-спектроскопии.

Correction for ‘Quantum tunneling dynamical behaviour on weakly bound complexes: the case of a CO2–N2 dimer’ by Miguel Lara-Moreno et al., Phys. Chem. Chem. Phys., 2019, 21, 3550–3557, DOI: 10.1039/c8cp04465a.

In the present work, a flash-PEO coating is developed on AZ31B alloy in a combination of silicate, phosphate, and fluoride based electrolyte in order to offer a green alternative to chromate conversion coatings. Multilevel active protection is achieved through synergetic combination of self-sealing effect of PEO coating itself and active inhibition provided by an organic inhibitor impregnated in PEO pores in a post-treatment step. The results indicate that flash-PEO coatings, loaded with organic corrosion inhibitors, can be recommended for exploitation on industrial level as an equally effective corrosion protection system alternative to CCC for paint-bearing and paint-free applications.

The review encompasses state-of-the-art strategies for design and fabrication of smart biomaterials for tissue engineering. The focus of the work is mainly put on metallic biomaterials with hybrid coatings consisting of bioceramic and polymeric layers with hierarchical organization and drug-eluting capacity. Key technologies and steps to design hybrid smart and multifunctional coatings on metallic cores for bone regeneration implants and cardiovascular stents are outlined, including additive manufacturing of titanium and magnesium alloys for permanent and temporary implant applications. Three levels of hierarchical surface functionalization are described: i) in situ modification of the core material, incorporating bioactive inorganic species and phases by means of ceramic coatings via anodic electrochemical treatments; ii) post-treatment application of polymer layers, monolithic or with specific porous breath figure topography; and iii) application of a cellular therapy component (single cell or cell sheet). Recent progress in incorporation of drug-eluting functionality into such materials via direct or nanocarrier-assisted loading is also highlighted., The authors gratefully acknowledge the support of the RTI2018- 096391-B-C33 (MCIU/AEI/FEDER, UE) and ADITIMAT-CM (S2018/ NMT-4411) projects. M. Mohedano and H. Mora-S ́anchez are grateful for the support of RYC-2017 21843 and PEJD-2019-POST/IND-16119, respectively. A. Santos-Coquillat is grateful for financial support from Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III Sara Borrell Fellowship CD19/00136. Equally, this work was financially supported by the Ministerio de Ciencia e Innovación (RTI2018-096328- B-I00).

International audience; Since their recent detection in interstellar clouds and circumstellar envelopes, polyyne and cyanopolyyne anions have raised the question of their possible mechanisms of formation, destruction, and excitation. These anions are observed in the same regions as the corresponding neutral species, with anion-to-neutral abundance ratios of a few percent. It is believed that the abundance ratios are controlled mainly by the radiative attachment processes. We present a quantum study of the radiative electron attachment and photodetachment rate constants for selected linear carbonchain anions, namely the already detected interstellar anions as well as other potential candidates. The rate constants are calculated within the rigid molecule approximation, with the attached or ejected electron described by a plane wave. A qualitative agreement is obtained with the previous accurate quantum results. For the radiative electron attachment process, the discrepancies between the quantum rate constants calculated here and the statistical rate constants currently used in astronomical models are relatively small for the shortest carbon chains but increase strongly with the number of atoms in the chain.

The hydrogen anion has never been observed in the interstellar medium, but it is most likely present in some interstellar regions. Since direct detection appears especially difficult, improving the knowledge of the astrochemical processes involving this anion should be valuable in defining a way of indirect detection. We present the first study of the radiative association of H− and CO to form the HCO− anion within a quantum time-independent approach. We use a state-of-the-art potential energy surface which has been calculated for the present study. The calculated radiative association rate coefficient is monotonically decreasing from 6 × 10−16 to 5 × 10−19 cm3 per molecule per s across the 0.01–1000 K temperature range. At the typical temperature of the cold interstellar medium, ∼10 K, the radiative association rate is ∼2 × 10−17 cm3 per molecule per s. On the other hand, the plane wave approximation is used to calculate the HCO radiative electron attachment rate coefficient. It is found to be almost constant and also equal to 2 × 10−17 cm3 per molecule per s. Setting aside the question of the abundances of the reactants of both processes, these results demonstrate that among the two gas-phase modes of production of the HCO− anion in cold interstellar medium considered in this study, the H− + CO radiative association is dominating below 10 K while the radiative electron attachment rate is larger above 10 K.

A two-dimensional rigid rotor model of the potential energy surface is developed for the collision of C3N- with He. Ab initio calculations are performed at the coupled cluster level with single and double excitations and using a perturbative treatment of triple excitations. An augmented correlation consistent polarized valence quadruple zeta basis set complemented with a set of mid-bond functions is chosen for these calculations. The global T-shaped minimum (De = 62.114 cm-1) is found at the intermolecular distance R = 6.42 a0. A secondary minimum (De = 41.384 cm-1) is obtained for the linear configuration C3N--He and for R = 9.83 a0. Calculations of the rovibrational bound states are carried out by using a discrete variable representation method based on Sturmian functions. The first theoretical prediction of the absorption spectra for the He-C3N- complex in the microwave region is also provided.

Lipid membranes exist essentially in two different phases. A phase transition can be triggered off either by changing the temperature or, isothermally, by varying an external factor such as ionic concentration, pH, organic solvents, etc. Since the isothermal transition may be induced at physiological temperature, it may play an important regulatory role in diverse cellular functions. Based on the Landau-Ginsburg theory, the thermotropic transitions of lipids has been described by a number of models. In the present work a dynamical model for an isothermal phase transition of phospholipids induced by ionic binding is proposed. The properties of the model show that by ionic binding, phospholipids may form spatial heterogeneous distributions of lipids in fluid and crystalline phases. This heterogeneity possibly being the cause of membrane instabilities, which favour enhanced vesicle fusions observed in the presence of Ca 2+ .