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This work assesses the role of the operational conditions upon the electro-activation of persulfate (electro-PS) using Ti/IrO2 Ta2O5 electrode for the decolorization of anthraquinone azo dye Disperse Blue 3 (DB3). The studied variables include current density (j) (5–80 mA cm−2), persulfate concentration based on the stoichiometric dose for complete DB3 mineralization (20–100%), temperature (30–90 °C) and pH (3–12) as well as the influence of dissolved oxygen. The persulfate activation from cathodic reduction was confirmed by linear sweep voltammetry (LSV). The increase in j enhanced the PS decomposition and, consequently, decolorization efficiency, because of the greater production of sulfate radicals (SO4•−). Besides, the combination of electro-PS with thermal activation resulted in a synergistic effect upon the DB3 mineralization. In the range 30–70 °C, electro-PS led to a significantly higher TOC conversion (above 60% at 40 mA cm−2) than sole heat-activated PS. This difference steeply decreased as temperature increases, achieving similar TOC conversion at 90 °C after 60 min.

The possibility to intensify the homogeneous photo-Fenton by increasing temperature (up to 90 °C) has been deeply investigated using phenol as model pollutant and treating a real landfill leachate effluent. TOC removal rate was significantly improved as temperature increases. The required irradiation time to mineralize 1 g/L of phenol using the stoichiometric amount of H2O2 and 10 mg/L Fe2+ decreases from 120 min at 50 °C to less than 30 min when the experiments were carried out at 90 °C. Besides, within this range, the value of H2O2 consumption efficiency (ηH2O2), defined here as g of TOC converted per g of H2O2 consumed, was maintained around 0.15, which confirm the scarce effect of thermal H2O2 decomposition into O2 and H2O. More interestingly, the Irradiation Energetic Efficiency, defined as the TOC converted per W-h of energy emitted to the solution, dramatically increased with temperature, with a maximum value of 1.04 g of TOC per W-h reached at 90 °C. These results significantly improve those reached using dark Fenton under comparable experimental conditions. Similar trend was observed when high temperature photo-Fenton was applied to landfill leachates, using the stoichiometric amount of H2O2 (2.12 g/g COD) and 10 mg/L Fe2+. The required irradiation time to achieve maximum TOC and COD removals (around 80%) was reduced from 180 to 45 min by increasing temperature from 50 to 90 °C and the irradiation efficiency increased 4-fold withing this range of temperature. In addition, a kinetic model has been proposed to fit TOC evolution in both phenol and the leachate treatment. According to this, firstly temperature promotes the rapid degradation of TOC by the hydroxyl radicals produced by Fenton reaction decreasing the wastewater turbidity and colour. Subsequently, photo-Fenton reaction plays a key role, promoting organic acids and other by-products mineralization. The results of this paper reveal that, far from being a drawback due to undesirable H2O2 thermal decomposition into O2 and H2O, high temperatures could be efficiently used to enhance the cost-efficiency of photoassisted processes. To the best of our knowledge, this is the first time that such a wide range of temperature up to 90 °C is explored. Thereby, the outcomes of this research confirm temperature as a promising way to intensify photoassisted treatments, reducing both the reaction time and the required energy (W-h) and operational costs to partially oxidized and/or mineralize organic matter in highly organic loaded wastewaters.

Cross couplings between simple allylic alcohols and aryl and vinyl boronic acids are efficiently catalyzed by nickel(0) catalysts and bidentate N-heterocyclic carbene/phosphine ligands. The bidentate nature of the ligand is shown to extend catalyst lifetime and enable high yields of the corresponding cross coupling products. X-ray crystallography confirms the bidentate nature of the ligand scaffold. Multistep cross coupling-alkene/alkyne insertions reactions are also conducted and the bidentate nature of the substrate makes the pendant phosphine of the ligand unnecessary.

The indiscriminate use of chlorantraniliprole has led Plutella xylostella (L.) (Lepidoptera: Plutellidae) populations from northeast of Brazil to resistance. There is no information in Brazil about the current status of P. xylostella resistance to other diamides and the mechanisms underlying it. The study aimed to assess the susceptibility of P. xylostella from brassica producing areas in the northeast of Brazil to three diamides: chlorantraniliprole, cyantraniliprole and flubendiamide by estimating concentration-response curves. In addition, the activity of detoxification enzymes and their inhibition were examined to exclude their association with the resistance. Activity of three detoxification enzyme complexes was assessed: esterase, glutathione S -transferase and mixed function oxidase. Low mortality (0–10%) was observed among all assessed field populations at label doses, suggesting control failure in the field. Resistance ratios (RR 50 ) for the populations varied from 7500- to 28 000-fold (chlorantraniliprole), from 12- to 2000-fold (cyantraniliprole), and from 2900- to 519 000-fold (flubendiamide). Cross-resistance among diamides was observed as expected. Significant synergism ratio [SR 50 = 2.22 (1.57–3.14)] for chlorantraniliprole was observed only by diethylmaleate, though not enough to explain diamide resistance. Although enzymatic activities varied significantly among populations, no correlation with levels of susceptibility was observed and metabolic detoxification is not a major factor associated with diamide resistance in these populations, which may be explained by target site alteration. These results show that very high resistance to diamides quickly developed in these populations of P. xylostella. The findings of this study suggest that novel insecticides must be wisely used to avoid quick selection of resistance and loss of the efficacy in the field.

In this work, bimetallic zerovalent iron-silver nanoparticles (NZVI-Ag) immobilized in calcium alginate beads were prepared and characterized. This material was tested as catalyst in the dechlorination and oxidation of 4-chlorophenol (CP-4). The bimetallic nanoparticles showed average size and BET surface area around 80 nm and 22 m2 g−1, respectively, with morphology and crystallinity typical of nanometric metallic iron. 4-CP dechlorination was more efficient at pH 3 than at pH 5 and at the former was completed in 30 min. Further addition of H2O2 allowed high TOC reduction, quite similar to the obtained with the bare metallic nanoparticles but with lower metal leaching.

In this work, a multivariate response surface methodology (RSM), was applied to analyze the effects of the synthesis variables that affect the reactivity of nanosized zero valent iron particles (NZVI), obtained by chemical reduction with sodium borohidride on the decoloration of azo dye Disperse Red 1 (DR1). Statistical analysis and data interpretation revealed that the generated model showed significant regression and fitting. The conditions that generated NZVI with higher reactivity correspond to [Fe 2+ ]:[BH 4 − ] molar ratio = 1:3, higher rates of reducing agent addition and lower pH (2–3). NZVI particles synthesized under the optimal conditions were characterized via XRD, BET surface area and electron microscopy. The results showed that the nanostructured material had composition, morphology and crystallinity typical of zero-valent iron, with BET surface area of ​​45 m 2 g −1 and an average particle size of 60 nm. NZVI yielded high color removal in fairly short time (around 98% in 10 min). Latter combination with H 2 O 2 allowed high mineralization.

Without extensive fitting, accurate prediction of transition metal chemistry is a challenge for semilocal and hybrid density funcitonals. The Random Phase Approximation (RPA) has been shown to yield superior results to semilocal functionals for main group thermochemistry, but much less is known about its performance for transition metals. We have therefore analyzed the behavior of reaction energies, barrier heights, and ligand dissociation energies obtained with RPA and compare our results to several semilocal and hybrid functionals. Particular attention is paid to the reference determinant dependence of RPA. We find that typically the results do not vary much between semilocal or hybrid functionals as a reference, as long as the fraction of exact exchange (EXX) mixing in the hybrid functional is small. For large fractions of EXX mixing, however, the Hartree-Fock-like nature of the determinant can severely degrade the performance. Overall, RPA systematically reduces the errors of semilocal functionals and delivers excellent performance from a single reference determinant for inherently multireference reactions. The behavior of dual hybrids that combine RPA correlation with a hybrid exchange energy was also explored, but ultimately did not lead to a systematic improvement compared to traditional RPA for these systems. We rationalize this conclusion by decomposing the contributions to the reaction energies, and briefly discuss the possible implications for double-hybrid functionals based on RPA. The correlation between EXX mixing and spin-symmetry breaking is also discussed.

Gastric and small intestinal organoids differentiated from human pluripotent stem cells (hPSCs) have revolutionized the study of gastrointestinal development and disease. Distal gut tissues such as cecum and colon, however, have proven considerably more challenging to derive in vitro. Here we report the differentiation of human colonic organoids (HCOs) from hPSCs. We found BMP signaling is required to establish a posterior Satb2+ domain in developing and postnatal intestinal epithelium. Brief activation of BMP signaling is sufficient to activate a posterior HOX code and direct human PSC-derived gut tube cultures into HCOs. In vitro, HCOs express colonic markers and contained colon-specific cell populations. Following transplantation into mice, HCOs undergo morphogenesis and maturation to form tissue that exhibits molecular, cellular, and morphologic properties of human colon. Together these data show BMP-dependent patterning of human hindgut into HCOs, which will be valuable for studying diseases including colitis and colon cancer.

We review the theory and application of adiabatic exchange–correlation (xc)-kernels for ab initio calculations of ground state energies and quasiparticle excitations within the frameworks of the adiabatic connection fluctuation dissipation theorem and Hedin’s equations, respectively. Various different xc-kernels, which are all rooted in the homogeneous electron gas, are introduced but hereafter we focus on the specific class of renormalized adiabatic kernels, in particular the rALDA and rAPBE. The kernels drastically improve the description of short-range correlations as compared to the random phase approximation (RPA), resulting in significantly better correlation energies. This effect greatly reduces the reliance on error cancellations, which is essential in RPA, and systematically improves covalent bond energies while preserving the good performance of the RPA for dispersive interactions. For quasiparticle energies, the xc-kernels account for vertex corrections that are missing in the GW self-energy. In this context, we show that the short-range correlations mainly correct the absolute band positions while the band gap is less affected in agreement with the known good performance of GW for the latter. The renormalized xc-kernels offer a rigorous extension of the RPA and GW methods with clear improvements in terms of accuracy at little extra computational cost.

In this paper we revisit some of the main aspects of the DAGS Key Encapsulation Mechanism, one of the code-based candidates to NIST’s standardization call for the key exchange/encryption functionalities. In particular, we modify the algorithms for key generation, encapsulation and decapsulation to fit an alternative KEM framework, and we present a new set of parameters that use binary codes. We discuss advantages and disadvantages for each of the variants proposed.

Regulation of the intestinal mucus layer by goblet cells is important for preventing inflammation and controlling infection. IL-33, a cytokine upregulated in inflammatory bowel disease and helminth infection, induces intestinal goblet cells, but the mechanism remains unclear. Enteroids are three-dimensional structures of primary small intestinal epithelial cells that contain all differentiated intestinal epithelial cell types. We developed an enteroid–immune cell coculture model to determine the mechanism through which IL-33 affects intestinal goblet cell differentiation. We report that IL-33 does not directly induce goblet cell differentiation in murine enteroids; however, IL-13, a cytokine induced by IL-33, markedly induces goblet cells and gene expression consistent with goblet cell differentiation. When enteroids are cocultured with CD90+ mesenteric lymph node cells from IL-33–treated mice, IL-33 then induces IL-13 secretion by group 2 innate lymphoid cells and enteroid gene expression consistent with goblet cell differentiation. In cocultures, IL-33–induced Muc2 expression is dependent on enteroid Il4ra expression, demonstrating a requirement for IL-13 signaling in epithelial cells. In vivo, IL-33–induced intestinal goblet cell hyperplasia is dependent on IL-13. These studies demonstrate that IL-33 induces intestinal goblet cell differentiation not through direct action on epithelial cells but indirectly through IL-13 production by goup 2 innate lymphoid cells.

Modern vehicular security architectures provision authorized vehicles with multiple short-term pseudonym certificates, so users can avoid tracking by rotating among certificates when signing messages. The large number of certificates in the system, however, makes revocation via Certificate Revocation Lists (CRLs) complex and/or inefficient. Two possible solutions for this issue are: (1) frequently provision non-revoked vehicles with few certificates, as done in the Cooperative Intelligent Transport Systems (C-ITS) standard; or (2) provision many encrypted certificates and periodically broadcast “activation codes” for controlling decryption by non-revoked vehicles, as proposed in Activation Codes for Pseudonym Certificates (ACPC), an extension of the Security Credential Management System (SCMS) standard. In this article, we compare such approaches in terms of computational efficiency and privacy preservation. We show that ACPC has advantages over both C-ITS (e.g., support for distributed caching) and CRLs (e.g., avoiding processing overheads on vehicles). We also discuss how ACPC can benefit from the unicast distribution of activation codes, with different trade-offs between privacy and bandwidth savings: getting as much privacy as C-ITS, but downloading 16-byte codes instead of hundreds of kilobytes, or fixing bandwidth costs (resp. privacy level) for a privacy degradation (resp. bandwidth usage) that grows logarithmically with the number of revocations.

Se realiza esta investigación con la finalidad de abordar globalmente la temática de liderazgo y gerencia en proyectos educativos y sociales. En particular se consideraran aspectos fundamentales de la gestión y el liderazgo como definiciones, características importancia en la comunidad educativa. Proyecto educativo y social son una forma eficaz de convertir las ideas en resultados. Se concluye que una educación de calidad tiene que sustentarse en una eficiente y excelente gestión educativa. Los proyectos se convierten en un punto de encuentro para que los miembros de la comunidad educativa alcanzando acuerdos y trabajando mancomunadamente, concienticen el poder que tienen cuando actúan en equipo y de manera organizada.

This study examines the relative importance of the different learning objectives for criminal justice education as identified by the Academy of Criminal Justice Sciences (ACJS). Three different populations (students, faculty, and professionals) completed a survey exercise in which they were required to rank order hypothetical job applicants who varied in competency on each of the ACJS learning objectives. In addition, students completed the same exercise pre- and post-completion of their required internship to determine if experience in the field affected their responses. Conjoint analysis was used to identify the relative importance of different learning objectives. While results indicate some similarities in responses across all three populations, several interesting differences were observed, and these may have important curricular implications for criminal justice programs.

The tomato leafminer, Tuta absoluta (Meyrick), is one of the most important pests of tomato worldwide. The use of chemicals is still the major tactic of control against this pest in Brazil, where spray overuse leads to resistance, frequently associated with control failures in the field. In this study, a survey of the susceptibility to indoxacarb, metaflumizone, chlorfenapyr, cartap, and abamectin aimed to determine the resistance status of T. absoluta populations. Also, the major enzyme systems associated with metabolic resistance were assessed to infer variability. The LC50 values varied among the populations for abamectin (0.54–3.38 mg a.i./L), cartap (93.1–589.8 mg a.i./L), chlorfenapyr (0.62–2.83 mg a.i./L), indoxacarb (0.86–2.89 mg a.i./L), and metaflumizone (0.35–7.44 mg a.i./L). Resistance ratios varied among populations being 6.2-, 6.4-, 4.6-, 3.3-, and 21.2-times for abamectin, cartap, chlorfenapyr, indoxacarb, and metaflumizone, respectively. Only the cartap confidence limits of the LC80 bracketed the recommended label concentration for three populations (Anapolis, Guaraciaba do Norte, and Tiangua), suggesting control failures. No cross-resistance was observed between indoxacarb and metaflumizone, and natural variation may explain the variability of response to this latter insecticide. The activity of enzymes frequently associated with metabolism of insecticides significantly differed among populations, and glutathione S-transferases and cytochrome P450-dependent monooxygenases were variable among the populations of T. absoluta, while alpha and beta-esterases were very homogeneous. T. absoluta resistance to abamectin and cartap has not been critical in Brazil despite their long use and together with chlorfenapyr appear to be an interesting option of rotation with indoxacarb, for which there is no cross-resistance to metaflumizone.

This work assesses the feasibility of using natural ilmenite as catalyst in NO3− photo-reduction with oxalic acid as reducing agent. The experimental set-up includes a magnetically stirred batch reactor equipped with a medium pressure Hg UV-lamp (30 W/m2). Experiments were carried out under N2 atmosphere at 25 °C, using 1–2 times the stoichiometric amount of C2O42- to reduce NO3− to N2. The reduction of NO3− to N2 via NO2− is, by far, the main route. Concurrently, the generation of NOx (g) via NO3− and NO2− reduction is also observed. The complete NO3− and C2O42- removal and a selectivity towards N2 > 93 % is achieved by using the stoichiometric C2O42- dose after 210 min, without the generation of undesirable NH4+. The residual NO2− concentration was lower than 0.5 mg N/L. Besides, doubling the C2O42- dose allowed the complete removal of nitrogen from the aqueous phase with a N2 selectivity > 97 %.

Code-based cryptography is one of the main areas of interest for NIST’s Post-Quantum Cryptography Standardization call. In this paper, we introduce DAGS, a Key Encapsulation Mechanism (KEM) based on quasi-dyadic generalized Srivastava codes. The scheme is proved to be IND-CCA secure in both random oracle model and quantum random oracle model. We believe that DAGS will offer competitive performance, especially when compared with other existing code-based schemes, and represent a valid candidate for post-quantum standardization.

The structural phase transitions of different materials, including metal to metal, metal to semiconductor, and semiconductor to semiconductor transitions, were explored using methods based on the random phase approximation. Transition pressures for Si, Ge, SiC, GaAs, ${\mathrm{SiO}}_{2}$, Pb, C, and BN from their stable low-pressure phases to certain high-pressure phases were computed with several semilocal density functionals and from the adiabatic connection fluctuation-dissipation formulation of density functional theory at zero temperature. In addition to the random phase approximation (RPA), three approximate beyond-RPA methods were also investigated to determine the impact of exchange-correlation kernel corrections. Results at finite temperature were obtained with the inclusion of zero-point energy contributions from the phonon spectra. We find that including temperature effects is most important for systems with nearly degenerate phases such as for boron nitride and carbon. In combination with thermal corrections, the kernel-corrected correlation methods deliver high accuracy compared to experimental data and can serve as a useful benchmark method in place of more expensive correlated calculations.

Using a second-order approximation to Random Phase Approximation renormalized (RPAr) many-body perturbation theory for the interacting density-density response function, we have developed a so-called higher-order terms (HOT) approximation for the correlation energy. In combination with the first-order RPAr correction, our new method faithfully captures the infinite-order correlation for a given exchange-correlation kernel, yielding errors of the total correlation energy on the order of 1% or less for most systems. For exchange-like kernels, our new method has the further benefit that the coupling-strength integration can be completely eliminated resulting in a modest reduction in computational cost compared to the traditional approach. When the correlation energy is accurately reproduced by the HOT approximation, structural properties and energy differences are also accurately reproduced, as we demonstrate for several periodic solids and some molecular systems. Energy differences involving fragmentation are challenging for the HOT method, however, due to errors that may not cancel between a composite system and its constituent pieces.

Cognitive theories suggest that working memory maintains not only the identity of recently-presented stimuli but also a sense of the elapsed time since the stimuli were presented. Previous studies of the neural underpinnings of working memory have focused on sustained firing, which can account for maintenance of the stimulus identity, but not for representation of the elapsed time. We analyzed single-unit recordings from the lateral prefrontal cortex (lPFC) of two macaque monkeys during performance of a delayed-match-to-category task. Each sample stimulus triggered a consistent sequence of neurons, with each neuron in the sequence firing during a circumscribed period of time. These sequences of neurons encoded both stimulus identity and the elapsed time. The encoding of the elapsed time became less precise as the sample stimulus receded into the past. These findings suggest that working memory includes a compressed timeline of what happened when, consistent with longstanding cognitive theories of human memory.

The ground state structural and energetic properties for rocksalt and cesium chloride phases of the cesium halides were explored using the random phase approximation (RPA) and beyond-RPA methods to benchmark the nonempirical SCAN meta-GGA and its empirical dispersion corrections. The importance of nonadditivity and higher-order multipole moments of dispersion in these systems is discussed. RPA generally predicts the equilibrium volume for these halides within 2.4% of the experimental value, while beyond-RPA methods utilizing the renormalized adiabatic LDA (rALDA) exchange-correlation kernel are typically within 1.8%. The zero-point vibrational energy is small and shows that the stability of these halides is purely due to electronic correlation effects. The rAPBE kernel as a correction to RPA overestimates the equilibrium volume and could not predict the correct phase ordering in the case of cesium chloride, while the rALDA kernel consistently predicted results in agreement with the experiment for all of the halides. However, due to its reasonable accuracy with lower computational cost, SCAN+rVV10 proved to be a good alternative to the RPA-like methods for describing the properties of these ionic solids.

Response surface methodology based on Box-Behnken design (BBD) was successfully applied for the optimization of the UV-LED/FeTiO3 activated persulfate (PS) process. Disperse Blue 3 (DB3) azo dye oxidation was carried out in a quartz jacketed stirred batch reactor using 405 nm UV at 10 W/m−2 as radiation source. The effects of temperature, catalyst concentration and persulfate dose upon the total organic carbon (TOC) removal were investigated. Optimum operating conditions were found to be: ilmenite: 320 mg/L−1, PS: 1.56 g/L−1 and 67°C. Under these conditions, 96% mineralization was achieved. Ecotoxicity of the final effluent was evaluated using Aliivibrio fischeri bacteria, finding a negligible toxicity., Comunidad Autónoma de Madrid and MINECO have supported this work through projects S2013/MAE-2716 and CTM2016-76454-R, respectively. Jefferson E. Silveira and Wendel S. Paz gratefully acknowledge the support from CAPES: Science Without Borders Program, Ministry of Education Brazil, under grants BEX-1046/13-6 and BEX-9476/13-0 respectively.