Catalytic hydrodechlorination as polishing step in drinking water treatment for the removal of chlorinated micropollutants

This Accepted Manuscript will be available for reuse under a CC BY-NC-ND license after 24 months of embargo periodThe presence of micropollutants in fresh waters represents an important challenge for drinking water treatment plants (DWTPs). In particular, the chlorinated ones are especially harmful given their high toxicity and strong bioaccumulation potential. The aim of this work is to evaluate the feasibility of catalytic hydrodechlorination (HDC) for the removal of a representative group of chlorinated micropollutants commonly found in the source waters of DWTPs: the antibiotic chloramphenicol (CAP), the anti-inflammatory diclofenac (DCF), the antibacterial agent triclosan (TCL) and the antidepressant sertraline (SRT). The complete degradation of the isolated micropollutants (3 mg L−1) was achieved in 1 h reaction time using a Pd/Al2O3 catalyst load of 0.25 g L−1 and a H2 flow rate of 50 N mL min−1. The experimental data were properly described by a pseudo-first order kinetic equation, obtaining degradation rate constants in the range of 0.32–1.56 L gcat−1 min−1 and activation energy values within 42–52 kJ mol−1. In all cases, the final reaction products were chlorine-free compounds and thus, HDC effluents were non-toxic (<0.1 TU). Remarkably, the catalyst showed a suitable stability upon five consecutive applications. The versatility of the process was demonstrated in the treatment of the micropollutants mixture in different aqueous matrices (mineral, surface and tap waters). Strikingly, the removal rate was not affected by the presence of co-existing substances, being the micropollutants completely removed in 15 min with 1 g L−1 catalyst concentration. Finally, the potential of HDC for the removal of trihalomethanes, by-products formed along the oxidation step by chlorination in DWTPs, was also demonstratedThis research has been supported by the Spanish MINECO thorough the project CTM2016-76454-R and by the CM through the project P2018/EMT-4341. J. Nieto-Sandoval thanks the Spanish MINECO for the FPI predoctoral grant (BES-2017- 081346). M. Munoz thanks the Spanish MINECO for the Ramón y Cajal postdoctoral contract (RYC-2016-20648

Uniqueness of the Fock quantization of fields with unitary dynamics in nonstationary spacetimes

The Fock quantization of fields propagating in cosmological spacetimes is not uniquely determined because of several reasons. Apart from the ambiguity in the choice of the quantum representation of the canonical commutation relations, there also exists certain freedom in the choice of field: one can scale it arbitrarily absorbing background functions, which are spatially homogeneous but depend on time. Each nontrivial scaling turns out into a different dynamics and, in general, into an inequivalent quantum field theory. In this work we analyze this freedom at the quantum level for a scalar field in a nonstationary, homogeneous spacetime whose spatial sections have S3 topology. A scaling of the configuration variable is introduced as part of a linear, time dependent canonical transformation in phase space. In this context, we prove in full detail a uniqueness result about the Fock quantization requiring that the dynamics be unitary and the spatial symmetries of the field equations have a natural unitary implementation. The main conclusion is that, with those requirements, only one particular canonical transformation is allowed, and thus only one choice of field-momentum pair (up to irrelevant constant scalings). This complements another previous uniqueness result for scalar fields with a time varying mass on S3, which selects a specific equivalence class of Fock representations of the canonical commutation relations under the conditions of a unitary evolution and the invariance of the vacuum under the background symmetries. In total, the combination of these two different statements of uniqueness picks up a unique Fock quantization for the system. We also extend our proof of uniqueness to other compact topologies and spacetime dimensions

Adsorption of micropollutants onto realistic microplastics: role of microplastic nature, size, age, and NOM fouling

This work aims at evaluating the role of nature, size, age, and natural organic matter (NOM) fouling of realistic microplastics (MPs) on the adsorption of two persistent micropollutants (diclofenac (DCF) and metronidazole (MNZ)). For such goal, four representative polymer types (polystyrene (PS), polyethylene terephthalate (PET), polypropylene (PP) and high-density polyethylene (HDPE)) were tested. MPs were obtained by cryogenic milling of different commercial materials (disposable bottles, containers, and trays), and fully characterized (optical microscopic and SEM images, FTIR, elemental analysis, water contact angle and pHslurry). The micropollutants hydrophobicity determined to a high extent their removal yield from water. Regardless of the MP's nature, the adsorption capacity for DCF was considerably higher than the achieved for MNZ, which can be related to its stronger hydrophobic properties and aromatic character. In fact, aromatic MPs (PS and PET) showed the highest adsorption capacity values with DCF (~100 μg g−1). The MP size also played a key role on its adsorption capacity, which was found to increase with decreasing the particle size (20–1000 μm). MPs aging (simulated by Fenton oxidation) led also to substantial changes on their sorption behavior. Oxidized MPs exhibited acidic surface properties which led to a strong decrease on the adsorption of the hydrophobic micropollutant (DCF) but to an increase with the hydrophilic one (MNZ). NOM fouling (WWTP effluent, river water, humic acid solution) led to a dramatic decrease on the MPs sorption capacity due to sorption sites blocking. Finally, the increase of pH or salinity of the aqueous medium increased the micropollutants desorptionThis research has been supported by the Autonoma University of Madrid and Community of Madrid through the project SI1-PJI-2019-00006, and by the Spanish MINECO through the project PID2019-105079RB-I00. Muñoz and J. Nieto-Sandoval thank the Spanish MINECO for the Ramón y Cajal postdoctoral contract (RYC-2016-20648) and the FPI predoctoral grant (BES-2017-081346), respectively. D. Ortiz thanks the Spanish MIU for the FPU predoctoral grant (FPU19/04816

Degradation of widespread cyanotoxins with high impact in drinking water (microcystins, cylindrospermopsin, anatoxin-a and saxitoxin) by CWPO

This Accepted Manuscript will be available for reuse under a CC BY-NC-ND license after 24 months of embargo periodThe occurrence of harmful cyanobacterial blooms has unabated increased over the last few decades, posing a significant risk for public health. In this work, we investigate the feasibility of catalytic wet peroxide oxidation (CWPO) promoted by modified natural magnetite (Fe3O4-R400/H2O2), as an inexpensive, simple-operation and environmentally-friendly process for the removal of the cyanotoxins that show the major impact on drinking water: microcystins (MC-LR and MC-RR), cylindrospermopsin (CYN), anatoxin-a (ATX) and saxitoxin (STX). The performance of the system was evaluated under ambient conditions and circumneutral pH (pH0 = 5) using relevant cyanotoxin concentrations (100–500 μg L−1). The nature of the cyanotoxins determined their reactivity towards CWPO, which decreased in the following order: MC-RR > CYN > MC-LR ≫ ATX > STX. In this sense, microcystins and CYN were completely removed in short reaction times (1–1.5 h) with a low catalyst concentration (0.2 g L−1) and the stoichiometric amount of H2O2 (2–2.6 mg L−1), while only 60–80% conversion was achieved with ATX and STX in 5 h. In these cases, an intensification of the operating conditions (1 g L−1 catalyst and up to 30 mg H2O2 L−1) was required to remove both toxins in 1 h. The impact of the main components of freshwaters i.e. natural organic matter (NOM) and several inorganic ions (HCO3−, HPO42-, SO42-) on the performance of the process was also investigated. Although the former led to a partial inhibition of the reaction due to HO· scavenging and catalyst coating, the latter did not show any remarkably effect, and the versatility of the process was finally confirmed in a real surface water. To further demonstrate the effectiveness of the catalytic system, the toxicity of both the initial cyanotoxins and the resulting CWPO effluents was measured with the brine shrimp Artemia salina. Remarkably, all CWPO effluents were non-toxic at the end of the treatment.This research has been supported by the Spanish MINECO through the project CTM-2016-76454-R and by the CM through the project P2018/EMT-4341. M. Munoz thanks the Spanish MINECO for the Ramón y Cajal postdoctoral contract (RYC-2016-20648). J. Nieto-Sandoval thanks the Spanish MINECO for the FPI predoctoral grant (BES-2017-081346

Resistance gene pool to co-trimoxazole in non-susceptible Nocardia strains

The soil-borne pathogen Nocardia sp. causes severe cutaneous, pulmonary, and central nervous system infections. Against them, co-trimoxazole (SXT) constitutes the mainstay of antimicrobial therapy. However, some Nocardia strains show resistance to SXT, but the underlying genetic basis is unknown. We investigated the presence of genetic resistance determinants and class 1-3 integrons in 76 SXT-resistant Nocardia strains by PCR and sequencing. By E test, these clinical strains showed SXT minimum inhibitory concentrations of ≥32:608 mg/L (ratio of 1:19 for trimethoprim: sulfamethoxazole). They belonged to 12 species, being the main representatives Nocardia farcinica (32%), followed by N. flavorosea (6.5%), N. nova (11.8%), N. carnea (10.5%), N. transvalensis (10.5%), and Nocardia sp. (6.5%). The prevalence of resistance genes in the SXT-resistant strains was as follows: sul1 and sul2 93.4 and 78.9%, respectively, dfrA(S1) 14.7%, blaTEM-1 and blaZ 2.6 and 2.6%, respectively, VIM-2 1.3%, aph(3')-IIIa 40.8%, ermA, ermB, mefA, and msrD 2.6, 77.6, 14.4, and 5.2%, respectively, and tet(O), tet(M), and tet(L) 48.6, 25.0, and 3.9%, respectively. Detected amino acid changes in GyrA were not related to fluoroquinolone resistance, but probably linked to species polymorphism. Class 1 and 3 integrons were found in 93.42 and 56.57% strains, respectively. Class 2 integrons and sul3 genes were not detected. Other mechanisms, different than dfrA(S1), dfrD, dfrF, dfrG, and dfrK, could explain the strong trimethoprim resistance shown by the other 64 strains. For first time, resistance determinants commonly found in clinically important bacteria were detected in Nocardia sp. sul1, sul2, erm(B), and tet(O) were the most prevalent in the SXT-resistant strains. The similarity in their resistome could be due to a common genetic platform, in which these determinants are co-transferred.This study was presented at the 54th Interscience Conference on Antimicrobial Agents and Chemotherapy, ICAAC2014, Washington, DC, USA. We thank Adrian Burton for editing and language assistance (http://physicalevidence.es/english/welcome). We are very grateful to all persons who took part in this study, and to the sample providers.S

Insights on the removal of the azole pesticides included in the EU Watch List by Catalytic Wet Peroxide Oxidation

The aim of this work is to evaluate the feasibility of the Catalytic Wet Peroxide Oxidation (CWPO) process using the inexpensive and environmentally friendly Fe3O4-R400 catalyst for the removal from water of a representative group of azole pesticides recently listed in the European Union (EU) Watch Lists (penconazole (PEN), prochloraz (PCZ), tebuconazole (TEB), tetraconazole (TET), metconazole (MET)). The complete removal of these pollutants (1000 μg L−1) was achieved in <1 h reaction time under ambient conditions using a catalyst concentration of 0.5 g L−1 and the stoichiometric dose of H2O2 (3 – 5 mg L−1) at a slightly acidic pH (pH0 = 5.0). To further demonstrate the effectiveness of the process, the ecotoxicity abatement was also considered. The initial toxicity of the pesticides and the CWPO effluents were evaluated with the brine shrimp Artemia salina and the bacterium Vibrio fischeri. Remarkably, the effluents were non-toxic for V. fischeri and a decrease of more than 80% in mortality was achieved for A. salina. Furthermore, the versatility of the system was proved in real water matrices (surface water and WWTP effluent), although a slight decrease on the oxidation rate was found due to the occurrence of organic matter and inorganic salts. The reactivity of the azole pesticides was finally compared with the achieved for other groups of pollutants included in the EU Watch Lists (pharmaceuticals, hormones, and neonicotinoid pesticides). Clearly, azole compounds showed the least reactivity to oxidation, suggesting that they can be used as general indicators of the overall efficiency of the proposed catalytic system for the removal of EU Watch Lists micropollutantsThis research has been supported by the Spanish AEI through the project PID2019-105079RB-100 and by the CM, Spain through the project P2018/EMT-4341. M. Munoz, N. Lopez-Arago and J. Nieto-Sandoval thanks the Spanish AEI for the Ramón y Cajal postdoctoral contract (RYC-2016-20648), the FPI predoctoral, Spain grant (PRE2020-09452) and the FPI postdoctoral, Spain grant (BES-2017-081346), respectivel

Store-Operated Calcium Entry in Breast Cancer Cells Is Insensitive to Orai1 and STIM1 N-Linked Glycosylation.

N-linked glycosylation is a post-translational modification that affects protein function, structure, and interaction with other proteins. The store-operated Ca2+ entry (SOCE) core proteins, Orai1 and STIM1, exhibit N-glycosylation consensus motifs. Abnormal SOCE has been associated to a number of disorders, including cancer, and alterations in Orai1 glycosylation have been related to cancer invasiveness and metastasis. Here we show that treatment of non-tumoral breast epithelial cells with tunicamycin attenuates SOCE. Meanwhile, tunicamycin was without effect on SOCE in luminal MCF7 and triple negative breast cancer (TNBC) MDA-MB-231 cells. Ca2+ imaging experiments revealed that expression of the glycosylation-deficient Orai1 mutant (Orai1N223A) did not alter SOCE in MCF10A, MCF7 and MDA-MB-231 cells. However, expression of the non-glycosylable STIM1 mutant (STIM1N131/171Q) significantly attenuated SOCE in MCF10A cells but was without effect in SOCE in MCF7 and MDA-MB-231 cells. In non-tumoral cells impairment of STIM1 N-linked glycosylation attenuated thapsigargin (TG)-induced caspase-3 activation while in breast cancer cells, which exhibit a smaller caspase-3 activity in response to TG, expression of the non-glycosylable STIM1 mutant (STIM1N131/171Q) was without effect on TG-evoked caspase-3 activation. Summarizing, STIM1 N-linked glycosylation is essential for full SOCE activation in non-tumoral breast epithelial cells; by contrast, SOCE in breast cancer MCF7 and MDA-MB-231 cells is insensitive to Orai1 and STIM1 N-linked glycosylation, and this event might participate in the development of apoptosis resistance

Application of catalytic hydrodechlorination for the fast removal of chlorinated azole pesticides in drinking water

Catalytic hydrodechlorination (HDC) is regarded as a promising purifying technology for drinking water treatment. So far, it has proved to be highly effective for the removal of different groups of chlorinated micropollutants including pharmaceuticals, neonicotinoid pesticides, personal care products or chloroacetic acids. The azole pesticides, recently included in the EU Watch Lists (Decisions 2020/1161 and 2022/1307), are a group of micropollutants of particular concern for drinking water given their high toxicity, persistence, and bioaccumulation potential. In this work, the feasibility of HDC for the removal of a representative group of chlorinated azole pesticides tebuconazole (TEB), tetraconazole (TET), prochloraz (PCZ), penconazole (PEN), metconazole (MET) and imazalil (IMZ)) is demonstrated, and their reactivity is compared with that observed for other halogenated micropollutant groups. Notably, all the pesticides investigated in this work (100 μg L− 1 ) were completely dechlorinated within 30 min under ambient conditions using a 1 wt% Pd/Al2O3 catalyst concentration of 0.25 g L− 1 and a H2 feeding of 50 mL N min− 1 . The experimental data were accurately described by a pseudo-first order kinetic equation and rate constant values in the range from 1.08 to 2.60 L gcat − 1 min− 1 were obtained. These values are quite close to those achieved for the most reactive neonicotinoid pesticides and significantly higher than the obtained for chloroacetic acids and most pharmaceuticals (e.g. diclofenac, sertraline or chlorpromazine). From the identification of the generated reaction intermediates and the final nonchlorinated products, sequential reaction pathways were proposed for each pollutant. Remarkably, despite the high toxicity exhibited by the azole pesticides tested, with LC50 values within the 0.4–7.0 mg L− 1 range using A. salina, HDC effluents were non-toxic in all cases. Furthermore, the catalyst showed a remarkable stability upon three consecutive runs. Finally, the versatility of the process was demonstrated in the treatment of real aqueous matrices such as DWTP and tap water, where no significant differences were found either in terms of activity or stabilityThis research has been supported by the Spanish MINECO through project PID2019-105079RB-I00 and by the CM through project P2018/ EMT-4341. J. Nieto-Sandoval and M. Munoz thanks the MINECO for the FPI contract (BES-2017-081346) and the Ramon ´ y Cajal postdoctoral contract (RYC-2016-20648), respectively. R. B. del Olmo thanks the Operational Program for Youth Employment and the Youth Employment Initiative (YEI) of the CM for his contract as Research Assistant (PEJ2020-AI/AMB-19161

Predictores de recuperación subjetiva en la esquizofrenia

The aim of the present study was to analyze factors that promote the experience of subjectiverecovery in people with a diagnosis of schizophrenia, and their relationship with objective recovery indicators. To do so, and after reviewing the existing literature, the predictive value of a set of different clinical and psychosocial variables on subjective recovery was evaluated of a sample of 43 adults with schizophrenia. Multiple regression analysis revealed that using adaptive coping strategies, low internalized stigma, and high self-esteem predicted 55% of the variance of subjective recovery (F = 12.5; p &lt; 0.0001). Negative symptoms and social functioning did not predict subjective recovery, in spite of significant correlations. Both the lack of predictive value of objective compared to subjective recovery measures, and the implications of the present findings for the treatment and promotion of increased recovery expectancies in this population are discussed.El objetivo del presente trabajo fue analizar los factores que promueven la experiencia subjetiva de recuperación en personas con diagnóstico de esquizofrenia, y su relación con los indicadores de recuperación objetiva. Para ello, tras revisar la literatura existente, se evalúo el valor predictivo de diferentes variables psicosociales y clínicas sobre la recuperación subjetiva en una muestra de 43 personas con esquizofrenia. El análisis de regresión múltiple reveló que el uso de estrategias adaptativas de afrontamiento, un bajo estigma internalizado y una elevada autoestima predijeron un 55% de la variable recuperación subjetiva (F = 12,5; p &lt; 0,0001). Los síntomas negativos y el funcionamiento social no predijeron recuperación subjetiva, pese a la presencia de correlaciones significativas. Se discuten los resultados en relación con la superior predicción de los indicadores subjetivos de recuperación, y se reflexiona sobre las implicaciones de estos resultados en el tratamiento y la promoción de mejores expectativas de recuperación en esta población