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Nursing education is in the process of incorporating critical thinking, social justice, and health inequality perspectives into educational structures, aspiring to help nursing students develop into professional nurses prepared to provide equal care. Norm criticism is a pedagogical philosophy that promotes social justice. This qualitative case study aimed to gain an understanding of and elaborate on an educational development initiative in which norm criticism was incorporated into the composition of a new campus‐based clinical learning environment for nursing education. By analyzing documents and interviews with the help of reflexive thematic analysis three themes were generated: "Intention to educate beyond nursing education," "Educating in alliance with society," and "The educative ambiguity of the Clinical Learning Centre." The case study indicates that the incorporation of norm criticism into a campus‐based clinical learning environment may encourage nursing students to evolve social skills for nursing practice that support health equality within healthcare. By collaborating with society, nursing education can considerably improve its educational frameworks in alignment with societal demands. However, the inclusion of norm criticism in a setting such as a campus‐based clinical learning environment entails a clash with established institutionalized norms and being perceived as too proximate to politics. [ABSTRACT FROM AUTHOR]

Transition metal catalysts with modified second‐coordination sphere employed in the electrocatalytic CO2 can result in increased activity or directed product selectivity. Calixarenes can form metal complexes and potentially catalyze reactions within its cavity, taking advantage of the surrounding phenols groups to tune the reactivity by second‐coordination sphere effects. Here, we present a Mn(I) bromotricarbonyl complex with phenanthroline‐functionalized calix[8]arene ligands capable of electrocatalytically reducing CO2 into different products with 2,2,2‐trifluoroethanol as proton donor. The selectivity of the reaction seems to be affected by the calixarene cavity: two calixarene‐free analogous complexes reduce CO2 to CO almost exclusively, while the calixarene complexes produce primarily CO, H2. Interestingly, in some cases the less frequently observed CH4 was also detected, albeit with low Faradaic efficiency. Thus, the manganese center placed within the calixarene cavity promotes the formation of reduced CO2 products by more than two electrons and two protons, affording CH4 in some cases. [ABSTRACT FROM AUTHOR]

This minireview presents efforts of synthetic chemists to mimic the active site of the copper monooxygenase enzymes peptidylglycine α‐hydroxylating monooxygenase (PHM), dopamine β‐monooxygenase (DβM), and tyramine β‐monooxygenase (TβM), all of which feature copper‐thioether ligation in their resting states. These monooxygenases are involved in the initial activation of O2 to generate neurotransmitters by the selective activation of C−H bonds of their corresponding substrates, resulting in subsequent hydroxylation. Attempts to emulate the N2S donor set provided by the two histidines and the methionine residues that coordinate to copper in the active site employ N2S and N3S‐type ligands, with the latter ones providing the best conditions for testing the reactivity of their CuI complexes with dioxygen. Identification of CuII‐superoxos as capable agents for C−H activation has provided support for these species as the key reactive intermediates in the enzymatic systems. Synthetic end‐on [CuII‐η1‐O2.−] and side‐on [CuII‐η2‐O2.−] cupric superoxos are capable of such transformations, which is related to the open question of whether the methionine S‐donor may act as a hemilabile ligand in biological systems. [ABSTRACT FROM AUTHOR]

Bis(benzimidazole)amine‐based copper complexes, with structural similarities to the active sites of Lytic Polysaccharide Monooxygenase enzymes (LPMOs), were tested for the oxidative degradation of cellulose. Spectroscopic characterization of the complexes, as well as structural authentication of one of them, confirm a tetragonal coordination environment with 3 nitrogen donors, as well as a thioether in axial positions. Aqueous oxidative degradation of cellulose was achieved with the CuII complexes and H2O2 as oxidant through putative cupric‐hydroperoxo intermediates. Conversion of cellulose was achieved in up to 67 % yield of soluble oligosaccharide derivatives at ambient temperature and pressure. The products were analyzed in aqueous solution by HPLC‐MS, confirming oxidative depolymerization of cellulose under ambient conditions, in an analogous fashion to LPMOs. [ABSTRACT FROM AUTHOR]

Discrepancies regarding the coordination environment, donor atoms, nuclearity, and oxidation state of the active site of particulate methane monooxygenase (pMMO), a copper‐dependent enzyme capable of activating the strong C−H bond of methane, persist despite numerous structural and spectroscopic studies. To address the proposed mono‐ (CuII) or bimetallic (2CuI) nature of the so‐called CuB site, we report the bis(benzimidazole)‐based NMe−N,N'‐(1‐Me‐2‐CH2C7H4N2)2C6H4 ligand (N4) and its copper complexes. In the solid state [Cu(N4)(ClO4)]ClO4 features tetragonal geometry defined by the chelating ligand and an axial perchlorate; geometric and EPR parameters are very close to those reported for the CuB site. Attempts to obtain a dicopper(I) analog resulted in [Cu(N4)][CuCl2], based on spectroscopic, electrochemical, and ESI‐MS data. Although these results support the assignment of CuB as a monometallic site, air exposure of [Cu(N4)][CuCl2] leads to ligand oxidation in the structurally characterized [Cu(N4=O)Cl], raising the possibility of distorted tetragonal Cu(I) centers activating O2 and oxidizing substrates, in C−H activation chemistry that may take place at CuB. [ABSTRACT FROM AUTHOR]

Large area single and bilayer graphene are grown on Pt/Ti/SiO2 substrates by hot filament chemical vapor deposition (HFCVD) with and without the assistance of Cu foil. The quality and number of graphene layers deposited on the substrate are assessed by Raman Spectroscopy. Atomic Force Microscopy (AFM) is used for assessing the surface topography of the graphene films grown on the Pt/Ti/SiO2 substrates. The microstructure and elemental analyses are performed by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The results show that bilayer graphene growth is facilitated by a copper foil placed nearby Pt/Ti/SiO2 substrate and by a high filament temperature in the HFCVD reactor. Monolayer graphene grows only when no copper foil is placed near the Pt/Ti/SiO2 substrate at a low filament temperature. The approach paves a novel pathway towards the layer‐controlled growth of graphene on Pt/Ti/SiO2 substrates by HFCVD for frontier applications. [ABSTRACT FROM AUTHOR]

The European Journal of Inorganic Chemistry takes pride in showcasing the high‐quality research produced by some of the currently most active scientists in Latin America. With this initiative, we seek to highlight the breadth and depth of the science developed in the region, and to enhance its visibility in the wider chemistry community. [ABSTRACT FROM AUTHOR]

Highlights • A new two-stage feature selection methodology for high-dimensional regression problems is proposed. • It is called wide spectrum feature selection for regression (WiSe). • Pearson correlation, Spearman rank correlation, Symmetrical uncertainty, and all their pairwise combinations are considered in the first stage. • In the second stage, the first-pass screened features are further selected using regression-dependent approaches. • Results confirm the increased predictive accuracy of models built after filtering out irrelevant features. Abstract Developing predictive models from industrial datasets implies the consideration of many possible predictor variables (features). Using all available features for data-driven modelling is not recommended, as most of them are expected to be irrelevant and their inclusion in the model may compromise robustness and accuracy. In this work, we present, test and compare a new two-stage feature selection method called wide spectrum feature selection for regression (WiSe). In the first stage, a combination of efficient bivariate filters analyzes linear and non-linear association patterns between predictors and responses, screening out clearly noisy features. In the second stage, the reduced set of retained features is subject to further selection in the scope of the predictive methods considered, optimizing their predictive performance. Three simulated datasets and an industrial case illustrate the effectiveness and benefits of applying WiSe to support model development in a wide range of high-dimensional regression problems. [ABSTRACT FROM AUTHOR]

Manufacturing analytics is of paramount importance in many plants today, and its relevance increases in the current big data context of Industry 4.0. The fields of statistics, chemometrics, and machine learning are expected to provide tools that effectively handle many of the characteristics of industrial data. In this paper, the task of image-based product classification is considered. This is a supervised learning problem where the input is an image and the output is a unique label attributed to the image from a finite set of labels corresponding to the available product classes. This is a prevalent and highly relevant industrial challenge and recent developments in deep learning have proven to be successful in increasing the image classification accuracy, providing state-of-the-art results. Thus, in this work, we leverage deep neural networks' (DNN) ability to automatically learn features from images and test their performance in a real industrial context for predicting the pellet shape. In order to accelerate the training of DNN, transfer learning is employed and a network previously developed for one task is adapted to predict pellet shape. Furthermore, other less complex techniques such as partial least squares discriminant analysis (PLS-DA) and random forests (RF) are also explored in order to assess the benefits of adopting DNN as opposed to current classifiers. An industrial image classification case study was utilized to compare PLS-DA, RF, and DNN models. Compared to the in situ classification system currently in use, increasingly complex models (PLS-DA and RF) were able to better utilize the same pre-defined features and improve prediction accuracy significantly. DNN obtained the highest accuracy on the independent test set, with the advantages of not requiring the a priori computation of image features since they are directly extracted from the raw images. Moreover, by visualizing the output of some layers of the DNN, it is possible to verify that activations occurred in regions that are indeed meaningful for the classification tasks, further supporting that DNN were effectively modelling the relevant features of the pellet. [ABSTRACT FROM AUTHOR]

Two cytotoxic copper(II) complexes with N-H and N -methylated benzimidazole-derived ligands (Cu- L 1 and Cu- L 1Me ; L 1 = bis(2-methylbenzimidazolyl)(2-methylthioethyl)amine, L 1Me = bis(1-methyl-2-methylbenzimidazolyl)(2-methylthioethyl)amine) were synthesized and exposed to human erythrocytes and molecular models of its membrane. The latter were bilayers built-up of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), classes of lipids present in the external and internal moieties of the human red cell membrane, respectively. Scanning electron microscopy (SEM) of erythrocytes incubated with solutions of both Cu(II) complexes showed that they induced morphological changes to the normal cells to echinocytes, and hemolysis at higher concentrations. Real-time observation of the dose-dependent effects of the complexes on live erythrocytes by defocusing microscopy (DM) confirmed SEM results. The formation of echinocytes implied that complex molecules inserted into the outer moiety of the red cell membrane. X-ray diffraction studies on DMPC and DMPE showed that none of these complexes interacted with DMPE and only Cu- L 1 interacted with DMPC. This difference was explained by the fact that Cu- L 1Me complex is more voluminous than Cu- L 1 because it has two additional methyl groups; on the other hand, DMPC molecule has three methyl groups in its bulky terminal amino end. Thus, by steric hindrance Cu- L 1Me molecules cannot intercalate into DMPC bilayer, which besides is present in the gel phase. These results, together with the increased antiproliferative capacity of the N -methylated complex Cu- L 1Me over that of Cu- L 1 are rationalized mainly based on its higher lipophilicity. [ABSTRACT FROM AUTHOR]

We present a data analytics framework for offline analysis of batch processes. The framework provides a unified setting for implementing several variants of feature oriented analysis proposed in the literature, including a new methodology based on the process variable's profiles presented in this article. It also integrates feature generation and feature analysis, in order to speed up the data exploration cycle, which is especially relevant for complex batch processes. The FOBA (Feature Oriented Batch Analytics platform) is described in detail and applied to several case studies regarding different analysis goals: visualization of the differences between the operation of two industrial units (dryers), quality prediction and end-of-batch process monitoring. The performance of the proposed methodology is also critically assessed and compared with other alternative analytical approaches currently in use. [ABSTRACT FROM AUTHOR]

Two cytotoxic copper(II) complexes with N–H and N-methylated benzimidazole-derived ligands (Cu- L 2 and Cu- L 2Me ) were synthesized and made to interact with human erythrocytes and molecular models of their plasmatic membranes. The latter consisted in lipid bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), lipids of the types present in the outer and inner monolayers of the human erythrocyte membrane, respectively. Initial assessment of the interaction of the complexes with DMPC and DMPE consisted of X-ray diffraction studies, which showed preferential interactions with the former. Scanning electron microscopy (SEM) of erythrocytes incubated with solutions of the Cu(II) complexes evidenced deformation of the cells to stomatocytes and knizocytes by Cu- L 2 and Cu- L 2Me due to interactions with the inner and outer leaflets of the cell membranes, respectively. This was further confirmed by real-time observation of the dose-dependent effects of the complexes on live erythrocytes by defocusing microscopy (DM). The combined observations, including the increased antiproliferative activity of the N-methylated complex Cu- L 2Me over that of Cu- L 2 is rationalized based on the higher lipophilicity of the former. This property would facilitate passive diffusion of Cu- L 2Me through the cell membrane, particularly in the initial stages when the DMPC-rich outer leaflet is involved. In contrast, the benzimidazole N–H groups of Cu- L 2 may participate in hydrogen bonding with DMPE polar groups; this result is consistent with the formation of stomatocyte induced by the latter complex. [ABSTRACT FROM AUTHOR]

Mixed N,S tripodal ligands bis(2,4-dimethylphenylthioethyl)(2-methylbenzimidazolyl)amine L 1 , bis(2,4-dimethylphenylthioethyl)(1-methyl-2-methylbenzimidazolyl)amine L 2 , and bis(1-methyl-2-methylbenzimidazolyl)(2-methylthioethyl)amine L 3 were employed to prepare the corresponding copper complexes. L 1 and L 2 associate weakly with Cu 2+ , while the reaction of CuI with L 1 affords [ L 1 CuI]. This was characterized in the solid state by the chelating tridentate coordination mode of L 1 , with a free thioether, and a terminal iodide, in contrast with the commonly observed Cu–I–Cu bridges. For L 3 , Cu + and Cu 2+ complexes are accessible as [ L 3 Cu]PF 6 , and the crystallographically characterized [ L 3 CuCl]Cl. The latter has a square pyramidal coordination around the Cu 2+ ion, with the thioether as an axial ligand that remains coordinated in solution, as evidenced by UV–Vis spectroscopy. [ABSTRACT FROM AUTHOR]

Reaction of Cu 2+ salts with the benzimidazole- N -methylated bis[(1-methyl-2-benzimidazolyl)ethyl]amine ligand 2BB results in either bi- or monometallic complexes. Spectroscopic and solid state characterization reveals either square pyramidal or trigonal bipyramidal coordination geometries around the cupric ions. In [{2BBCu(μ-F)} 2 ](BF 4 ) 2 , the dicopper structure is determined by the bridging nature of the fluoro ligands, which complement the T-shape arrangement of N 3 donors provided by 2BB to define a square pyramidal (or capped distorted tetrahedral) coordination geometry. The monocopper complexes 2BBCuCl 2 and [2BBCu(H 2 O) 2 ](OTf) 2 are characterized by a trigonal bipyramidal geometry both in solution and in the solid state. In all complexes, the T-shape N 3 donor set of 2BB is analogous to the coordination environment of the copper ions provided by a ‘histidine brace’ and an additional histidine imidazole in the active site of polysaccharide monooxygenases. [ABSTRACT FROM AUTHOR]

Abstract: Soft sensors (or inferential sensors) have been demonstrated to be an effective solution for monitoring quality performance and control applications in the chemical industry. One of the key issues during the development of soft sensor models is the selection of relevant variables from a large array of measurements. A subset of variables that are selected based on first principles and statistical correlations eases the model development process. The resulting model will perform better and will be easier to maintain during the deployment stage. In the current literature, data-driven variable selection methods have been investigated within the context of spectroscopic data and bioinformatics. In these studies, the variable selection methods assume that the inherent correlation in the entire data set remains fixed. This is not the case in common industrial processes. In this paper, existing variable selection methods based on partial least squares (PLS) will first be evaluated. Second, we will present a new approach called moving window variable importance in projection (MW-VIP) to target the selection of correlations present in segments or small clusters. Finally, a set of new evaluation criteria will be presented along with industrial data set modeling results to demonstrate the effectiveness of our proposed approach. [Copyright &y& Elsevier]

Abstract: Reaction of the chiral ligands (1S,4S)-2,5-bis(6-methylpyridyl)-diazabicyclo[2.2.1]heptane (L1 ) and (1S,4S)-2,5-bis(1-methyl-2-methylbenzimidazolyl)-diazabicyclo[2.2.1]heptane (L2 ) with CuCl2 results in the hydroxo-bridged dicopper complexes [(L1 )Cu2(μ-OH)(H2O)Cl3] (3), and [(L2 )Cu2(μ-OH)(H2O)Cl3] (4). Both chiral complexes were characterized spectroscopically, and 3 in the solid state by X-ray crystallography, confirming they are structurally related to their previously reported copper acetate analogues (1 and 2) due to their hydroxo-bridged bimetallic core. The achiral ligand analogues N,N′-bis(2-picolyl)piperazine (L3 ) and N,N′-bis(1-methyl-2-methylbenzimidazolyl)piperazine (L4 ) were employed to obtain the corresponding complexes with CuCl2, affording the chloro-bridged [(L3 )(CuCl)2(μ-Cl)2]n (5) and [(L4 )(CuCl)2(μ-Cl)2] (6), neither of which features a bridging hydroxo ligand; instead, complex 5 was structurally characterized as a coordination polymer. The acetate-derived complexes 1 and 2 are active in oxidative C–C coupling of 2,4-di-tert-butylphenol, while 3 and 4 have low activity; the achiral complexes 5 and 6, lacking a bridging hydroxo ligand, are inactive in this reaction. [Copyright &y& Elsevier]

Keywords: C-H activation; Copper; Monooxygenases; Oxidation; Thioethers EN C-H activation Copper Monooxygenases Oxidation Thioethers 1 1 1 02/01/22 20220111 NES 220111 B The Front Cover b shows the synergic action of copper and sulfur in thioether-containing copper monooxygenases that generate mammalian and invertebrate neurotransmitters. The review reports efforts of synthetic chemists to mimic the active sites of peptidylglycine -hydroxylating monooxygenase, dopamine -monooxygenase, and tyramine -monooxygenase. Front Cover: Thioether-Containing Copper Complexes as PHM, D M, and T M Model Systems (Eur. J. Inorg. [Extracted from the article]

Cover Feature: Cellulose Depolymerization with LPMO-inspired Cu Complexes (ChemCatChem 22/2021) Biomass, catalysis, LPMO, biomimetic, copper Keywords: biomass; catalysis; LPMO; biomimetic; copper EN biomass catalysis LPMO biomimetic copper 4654 4654 1 11/24/21 20211122 NES 211122 B The Cover Feature b represents the oxidative depolymerization of cellulose, affording cellobiose, levoglucosan, and gluconic acid as water-soluble products. [Extracted from the article]

Abstract: The molecular interactions of 5,6-dichloro-2-(trifluoromethyl)-1H-benzimidazole (G2), an antiprotozoa with poor aqueous solubility, with 2-hydroxypropyl-α-cyclodextrin (HPαCD), methyl-β-cyclodextrin (MβCD) and 2-hydroxypropyl-β-cyclodextrin (HPβCD) were examined. The aqueous solubility enhancement by cyclodextrins (CDs) was evidenced in phase-solubility diagrams, and the stoichiometry of G2/CD systems was determined by Job''s plots. Two-dimensional NMR spectroscopic data revealed that a different mode of interaction took place between G2 and CDs in solution. With HPαCD, a non-inclusion complex was generated. In the case of MβCD, a typical host–guest system was obtained and with HPβCD a partial inclusion complex through the narrow side of the macrocycle was formed. ESI-mass spectrometric data confirmed the stoichiometry and mode of interaction of these systems in solution. Solid-state characterization (scanning calorimetry and powder X-ray diffraction) supported the inclusion complex formation. The leishmanicidal activity, trypanocidal activity and non-toxic profile of G2/MβCD showed the advantages of using this inclusion complex to promote the biological assays extension of G2. [Copyright &y& Elsevier]

Abstract: Reaction of p-tert-butylcalix[8]arene 1 with 2,6-bis(chloromethyl)pyridine results in the regioselective introduction of the nitrogen-containing heterocycle to the 1 and 5 phenolic positions. The deprotonated form of the 1,5-bridged compound 2 acts as a dianionic ligand toward Cs+. The dicesium complex [2·Cs2O(H2O)], which has water molecules as additional ligands for the cesium cations, was characterized by X-ray crystallography. [Copyright &y& Elsevier]

Abstract: Octakis(dimethylsiloxy)-octa-p-tert-butylcalix[8]arene was prepared from the parent p-tert-butylcalix[8]arene and 1,1,3,3-tetramethyldisilazane. Desilylation of the siloxy-calix[8]arene with tetrabutylammonium fluoride hydrate under different conditions afforded di- and tetraanionic derivatives. Determination of the solid state structure of the dianion revealed the formation of an inclusion compound with one tetrabutylammonium cation inside the macrocyclic cavity. [Copyright &y& Elsevier]

: PurposeTo report a new treatment for acquired periodic alternating nystagmus in which medical therapy with baclofen was not tolerated.: DesignInterventional case report and literature review.: InterventionSimultaneous adjustable bilateral retroequatorial horizontal rectus muscle recessions.: Main outcome measuresOcular alignment and ocular motility recordings.: ResultsA 30-year-old man had blurred vision after an emergency left temporal craniotomy for gunshot wounds. Ophthalmologic examination revealed periodic alternating nystagmus that was documented by an infrared electronystagmogram. Baclofen was started but was not tolerated. Bilateral lateral and medial retroequatorial rectus muscle recessions were performed and were successful in the treatment of this patient.: ConclusionSimultaneous bilateral retroequatorial horizontal rectus recessions may be an effective treatment for intractable acquired periodic alternating nystagmus. [Copyright &y& Elsevier]

The Schiff base copper(II) complexes (1)–(6) were prepared and characterised by mass, IR, and electronic spectra. Their solid states structures, determined by X-ray crystallography, indicate that the geometry around copper is determined by a combination of steric and electronic effects, as well as crystal packing forces. Thus, complex (1) is the only one in the series to have a square planar geometry. In contrast, complexes (2) and (3) display deformed square planar geometries, despite the small steric effect of the N-cyclopropyl and cyclobutyl groups. Furthermore, a purely electronic argument, based on which complexes (5) and (6) must have deformed tetrahedral structures, fails to account for the observed stepped square planar structures. Finally, complex (4) also has a stepped square planar geometry. [Copyright &y& Elsevier]

Purpose: To describe a patient with congenital nystagmus that decreased in one eye after the development of a cavernous sinus meningioma.Design: Interventional case report.Methods: A 45-year-old man with congenital nystagmus, albinism, and high myopia presented with right upper eyelid ptosis that was corrected surgically on three occasions during a 3-year period. An episode of syncope was followed by diagnostic evaluation that disclosed a cavernous sinus meningioma. He commented that his right eye nystagmus progressively decreased. He was found to have ophthalmoplegia on the right eye due to nerve compression by the meningioma.Results: A magnetic resonance imaging scan disclosed a cavernous sinus meningioma extending into the parachiasmal and clival areas. A biopsy specimen of the lesion demonstrated a meningioma.Conclusions: Any patient with acquired ptosis should have a complete ophthalmic examination, including evaluation of extraocular motility. [ABSTRACT FROM AUTHOR]

A 19-year-old woman presented with frontal headaches, papilledema, and binocular horizontal double vision due to a left VI nerve palsy. MRV demonstrated sagittal sinus and bilateral transverse sinus thrombosis. The clinical and neuro-radiologic signs resolved after anticoagulation. [Copyright &y& Elsevier]

The hafnium imido dichloride (2,6-i-Pr2C6H3)N&z.dbnd6;Hf(THF)2Cl2 (1) reacts with two equivalents of Ph3SiLi(THF)3 to yield the corresponding disilyl complex (2,6-i-Pr2C6H3)N&z.dbnd6;Hf(THF)2(SiPh3)2 (2) in low yield. Compound 2 was crystallographically characterized. The hafnium monosilyl complex (2,6-i-Pr2C6H3)N&z.dbnd6;Hf(4-t-BuC5H4N)2Cl[Si(SiMe3)3] (4) was synthesized in a similar manner from (2,6-i-Pr2C6H3)N&z.dbnd6;Hf(4-t-BuC5H4N)2Cl2 (3) and one equivalent of (Me3Si)3SiK in good yield. The Cp*-containing hafnium imido complex {Cp*HfCl[μ-N(2,6-i-Pr2C6H3)]}2 (5) was prepared by thermolysis of Cp*Hf[Si(SiMe3)3][NH(2,6-i-Pr2C6H3)]Cl via loss of (Me3Si)3SiH. Complex 5 was crystallographically characterized. Attempts to prepared derivatives of 5 with reactive σ-bonds resulted in the formation of Cp*-cyclometallated species. [Copyright &y& Elsevier]

Investigates the mechanistic aspects of samarium-catalyzed redistribution of arene C-H and arylsilane Si-C bonds. Observation of the decomposition reaction of the compounds; Measurement on the law rate of the process; Activation of the Si-H.

The article titled "Cover Feature: Monocopper model of CuB site of pMMO in N4‐environment oxidizes C‐H bonds" discusses the activation of dioxygen by a copper(I) complex with tetragonal coordination environment provided by an N4‐ligand. The complex undergoes oxidation of the metal center to copper(II) while acquiring one oxygen atom as part of the ligand. This research suggests that dioxygen activation at the tetragonal Cu(I) active site of the copper‐dependent particulate methane monooxygenase (pMMO) should be further investigated. The article is authored by Hugo C. Hernández‐Toledo, Marcos Flores‐Alamo, and Ivan Castillo. [Extracted from the article]

• Calixarene derivative with phenanthroline moiety acts as nitrogen ligand for nickel complexes. • The chelating phenantrholine places nickel (II) ions within large calix[8]arene cavity. • Ni(II) complexes are catalyst precursors for electrochemical reduction of carbon dioxide. The electrochemical behavior and catalytic activity for the electroreduction of CO 2 of complexes of Ni(II) containing phenanthroline-based ligands, with or without a calixarene scaffold, were tested. The complexes were characterized by spectroscopic techniques, and their electrocatalytic properties determined by cyclic voltammetry. With water as proton source the complex [(1,5-(2,9-dimethyl-1,10-phenanthro)- p-tert -butylcalix[8]arene)NiCl 2 ] (1) presented a significant increase in current at E = −2.36 V (relative to Ag/AgCl reference electrode) when reduced under an atmosphere of CO 2 , indicating that an electrocatalytic process occurs. Thus, calix[8]arenes that feature a phenanthroyl moiety as bidentate N -ligands, and an intramolecular proton source in the phenolic –OH groups, afford Ni(II) electrocatalysts for the reduction of CO 2. [ABSTRACT FROM AUTHOR]

Discusses the crystal structure of O-(2-tert-Butyl-6-dimethylthiocarbamoyl-4-methylphenyl) N,N-dimethylthiocarbamate dichloromethane solvate. Torsion angle between the planes of the thiocarbamate and carbonothioyl fragments; Molecular structure of the compound; Packing of the dichloromethane molecules along pseudo-channels.

The aim to access linked tetravanadate [V4O12]4− anion with mixed copper(II) complexes, using α-amino acids and phenanthroline-derived ligands, resulted in the formation of four copper(II) complexes [Cu(dmb)(Gly)(OH2)]2[Cu(dmb)(Gly)]2[V4O12]·9H2O (1) [Cu(dmb)(Lys)]2[V4O12]·8H2O (2), [Cu(dmp)2][V4O12]·C2H5OH·11H2O (3), and [Cu(dmp)(Gly)Cl]·2H2O (4), where dmb = 4,4′-dimethioxy-2,2′-bipyridine; Gly = glycine; Lys = lysine; and dmp = 2,9-dimethyl-1,10-phenanthroline. The [V4O12]4− anion is functionalized with mixed copper(II) units in 1 and 2; while in 3, it acts as a counterion of two [Cu(dmp)]2+ units. Compound 4 crystallized as a unit that did not incorporate the vanadium cluster. All compounds present magnetic couplings arising from Cu⋯O/Cu⋯Cu bridges. Stability studies of water-soluble 3 and 4 by UV–Vis spectroscopy in cell culture medium confirmed the robustness of 3, while 4 appears to undergo ligand scrambling over time, resulting partially in the stable species [Cu(dmp)2]+ that was also identified by electrospray ionization mass spectrometry at m/z = 479. The in vitro cytotoxicity activity of 3 and 4 was determined in six cancer cell lines; the healthy cell line COS-7 was also included for comparative purposes. MCF-7 cells were more sensitive to compound 3 with an IC50 value of 12 ± 1.2 nmol. The tested compounds did not show lipid peroxidation in the TBARS assay, ruling out a mechanism of action via reactive oxygen species formation. Both compounds inhibited cell migration at 5 µM in wound-healing assays using MCF-7, PC-3, and SKLU-1 cell lines, opening a new window to study the anti-metastatic effect of mixed vanadium–copper(II) systems. [ABSTRACT FROM AUTHOR]

Polysaccharide oxidative depolymerization is highly desirable to achieve recalcitrant biomass valorization. Inspired by recently discovered Lytic Polysaccharide Monooxygenases, mononuclear copper complexes have been prepared and studied in the literature. However, the activities were evaluated on different substrates and under various conditions. In this work we intended to establish a robust and reproducible activity assay, in aqueous solution at a pH close from neutrality and under mild conditions. We have evaluated several complexes on substrates of increasing complexity: the model substrate para‐nitrophenyl‐β‐D‐glucopyranoside (p‐NPG), cellobiose (glucose dimer), as well as on extended substrates (chitin, cellulose and bagasse from agave). The different assays were compared and proof‐of‐concept that bioinspired complexes can oxidatively promote polysaccharide depolymerization was obtained. Finally, we measured level of hydroxyl radicals released by the complexes under comparable experimental conditions and mechanistic pathways are discussed. [ABSTRACT FROM AUTHOR]

Equipment degradation is ubiquitous in the Chemical Process Industry (CPI), causing significant losses in efficiency, controllability, and plant economy, as well as an increased environmental fingerprint and additional operational safety risks. The case of fouling in heat exchangers, in particular, is well-known and pervasive but still hard to cope with, given the complexity of the underlying mechanisms and the difficulty of assessing its extension in real-time. This problem becomes even more complex in batch processes producing different products, where multiple recipes are used, bringing additional variability and new challenges to the analysis. In this work, we propose a functional data-driven approach for streamlining the analysis and monitoring of the progression of fouling taking place in heat exchangers in multiproduct batch processes. With the approach developed and presented in this paper, process analysis can be efficiently conducted by integrating historical data with engineering knowledge. Furthermore, a surrogate measure of fouling extension in heat exchangers is proposed, that can be readily implemented as an equipment health indicator (EHI) leading to a safer operation of the heat exchanger. [ABSTRACT FROM AUTHOR]

Two novel Iron (II) complexes featuring tetrapodal bis(benzimidazole)amino thio- and selenoether ligands (LS and LSe) were synthesized, characterized, and tested as electrocatalysts for the hydrogen evolution reaction. The bromide complexes [Fe( LS , LSe )Br 2 ] (1–2) are highly insoluble, but their DMSO solvates were characterized by single crystal X-ray diffraction, revealing an octahedral coordination environment that does not feature coordination of the chalcogen atoms. The corresponding triflate derivatives [Fe(LS , LSe)(MeCN) 3 ]OTf 2 (1c-2c) were employed for electrocatalytic proton reduction, with 1c exhibiting higher activity, thus suggesting that the thioether may participate as a more competent pendant ligand for proton transfer. Bis(benzimidazole)-based Iron(II) complexes are competent Hydrogenase-inspired hydrogen evolution electrocatalysts that feature potentially proton-accepting intramolecular thio- and selenoethers groups. [Display omitted] • Synthesis and characterization of benzimidazole-based Fe(II) complexes • Solid-state structures of Fe(II) complexes show non-coordinated selenoether groups. • Proton reduction evidenced by cyclic voltammetry. • Fe(I) proposed as active species in electrocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

Functionalization of the phenolic rim of p‐tert‐butylcalix[8]arene with phenanthroline to create a cavity leads to formation of two regioisomers. Substitution of positions 1 and 5 produces the known C2v‐symmetric regioisomer 1,5‐(2,9‐dimethyl‐1,10‐phenanthroyl)‐p‐tert‐butylcalix[8]arene (L1,5), while substitution of positions 1 and 4 produces the Cs‐symmetric regioisomer 1,4‐(2,9‐dimethyl‐1,10‐phenanthroyl)‐p‐tert‐butylcalix[8]arene (L1,4) described herein. [Cu(L1,4)I] was synthesized from L1,4 and CuI in good yield and characterized spectroscopically. To evaluate the effect of its cavity on catalysis, Ullmann‐type C−S coupling was chosen as proof‐of‐concept. Selected aryl halides were used, and the results compared with the previously reported Cu(I)/L1,5 system. Only highly activated aryl halides generate the C−S coupling product in moderate yields with the Cu(I)/L1,4 system. To shed light on these observations, detailed computational investigations were carried out, revealing the influence of the calix[8]arene macrocyclic morphology on the accessible conformations. The L1,4 regioisomer undergoes a deformation that does not occur with L1,5, resulting in an exposed catalytic center, presumably the cause of the low activity of the former system. The 1,4‐connectivity was confirmed in the solid‐state structure of the byproduct [Cu(L1,4−H)(CH3CN)2] that features Cu(I) coordinated inside a cleft defined by the macrocyclic framework. [ABSTRACT FROM AUTHOR]

We explore the use of tools from Riemannian geometry for the analysis of symmetric positive definite matrices (SPD). An SPD matrix is a versatile data representation that is commonly used in chemical engineering (e.g., covariance/correlation/Hessian matrices and images) and powerful techniques are available for its analysis (e.g., principal component analysis). A key observation that motivates this work is that SPD matrices live on a Riemannian manifold and that implementing techniques that exploit this basic property can yield significant benefits in data-centric tasks such as classification and dimensionality reduction. We demonstrate this via a couple of case studies that conduct anomaly detection in the context of process monitoring and image analysis. • Mathematical introduction to Riemannian manifolds and their geometric analysis. • Framework (and code) for the analysis of SPD matrices through Riemannian geometry. • Benefits of geometric approach to data analysis illustrated through two real world case studies. [ABSTRACT FROM AUTHOR]

Development of C−N coupling methodologies based on Earth‐abundant metals is a promising strategy in homogeneous catalysis for sustainable processes. However, such systems suffer from deactivation and low catalytic activity. We here report that encapsulation of Cu(I) within the phenanthroyl‐containing calix[8]arene derivative 1,5‐(2,9‐dimethyl‐1,10‐phenanthroyl)‐2,3,4,6,7,8‐hexamethyl‐p‐tert‐butylcalix[8]arene (C8PhenMe6) significantly enhances C−N coupling activity up to 92 % yield in the reaction of aryl halides and aryl amines, with low catalyst loadings (2.5 % mol). A tailored multiscale computational protocol based on Molecular Dynamics simulations and DFT investigations revealed an oxidative addition/reductive elimination process of the supramolecular catalyst [Cu(C8PhenMe6)I]. The computational investigations uncovered the origins of the enhanced catalytic activity over its molecular analogues: Catalyst deactivation through dimerization is prevented, and product release facilitated. Capturing the dynamic profile of the macrocycle and the impact of non‐covalent interactions on reactivity allows for the rationalization of the behavior of the flexible supramolecular catalysts employed. [ABSTRACT FROM AUTHOR]

The catalytic activity of Cu(i) confined within a phenanthroline-containing calix[8]arene derivative was tested in C–S cross-coupling reactions. The substrate selectivity, solvent dependence, and catalyst loading differ significantly from those reported for bimetallic molecular systems. The putative monomeric complex represents the first calix[8]arene functionalised for endo-oriented metal chelation used as a nanoreactor. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this work is to study the molecular association that occurs between 2-hydroxypropyl-β-cyclodextrin (HPβCD) and 6-chloro-5-(1-naphthyloxy)-2-(trifluoromethyl)-1H-benzimidazole (RCB20), an antiparasitic compound recently found by our research group, with poor aqueous solubility. The complex stability constant and stoichiometric ratio determined by phase-solubility diagram and Job’s plot provided evidence that HPβCD enhanced water solubility of RCB20 through inclusion complex formation. Two-dimensional 1H NMR spectroscopy is used to study the molecular arrangement of inclusion complex in solution. These results are further supported using molecular modeling studies. In the solid state, the complexation is confirmed by differential scanning calorimetry, powder X-ray diffraction, and scanning electron microscopy. Finally, RCB20/HPβCD complex has better activity than RCB20 against the adult and muscle larvae phase of Trichinella spiralis. [ABSTRACT FROM AUTHOR]

• Hybrid modeling has been attracting the interest of the scientific community for almost 30 years. • Big data and the industry 4.0 bring opportunities for new hybrid modeling solutions. • We review hybrid modeling schemes, their training, validation and applications. • Usually mechanistic models are improved by data-driven models. • There is the need for a generic framework balancing prior and data-driven knowledge. The chemical processing industry has relied on modeling techniques for process monitoring, control, diagnosis, optimization, and design, especially since the third industrial revolution and the emergence of Process Systems Engineering. The fourth industrial revolution, connected to massive digitization, made it possible to collect and process large volumes of data triggering the development of data-driven frameworks for knowledge extraction. However, one must not leave behind the successful solutions developed over decades based on first principle mechanistic modeling approaches. At present, both industry and researchers are realizing the need for new ways to incorporate process and phenomenological knowledge in big data and machine learning frameworks, leading to more robust and intelligible artificial intelligence solutions, capable of assisting the target stakeholders in their activities and decision processes. In this article, we review hybrid modeling techniques, associated system identification methodologies and model assessment criteria. Applications in chemical and biochemical processes are also referred. [ABSTRACT FROM AUTHOR]

Introduction: Systemically administered cannabinoids can reduce intraocular pressure (IOP), but produce undesirable cardiovascular and central nervous system effects. In a chronic model of ocular hypertension, we examined the efficacy of acute topical administration of WIN55212-2 (WIN) in a novel commercially available vehicle and in combination with timolol. Methods: IOP was chronically elevated by the surgical ligature of vortex veins in Sprague Dawley rats. IOP was measured by using Goldmann applanation tonometry. IOP, blood pressure (BP), and heart rate (HR) were measured at baseline and 30, 60, 90, and 120 min after the topical administration of WIN 1.0%, 0.25%, 0.06%, or 0.015%, the commercially available vehicle, timolol 0.5%, or a combination of WIN and timolol. SR141716 (CB1 antagonist) or SR144528 (CB2 antagonist) was administered topically 30 min before WIN to determine receptor specificity. To determine ocular and systemic penetration, 3H WIN 55212-2 was administered topically and tissues were collected at 60 and 120 min. Ocular irritation was evaluated by slit-lamp examination (SLE) at baseline and 120 min. Results: WIN significantly decreased IOP in the hypertensive eye, with no BP or HR effects. SR141716 pretreatment significantly inhibited the IOP effects of WIN 1.0% in a dosedependent manner, while SR 144528 was not as effective. No significant additive effects were observed by combining WIN (0.5% or 1.0%) with timolol 0.5%. WIN was retained in ocular tissue with a t1/2 of 80–100 min. SLE at 120 min revealed no solvent or drug-related toxic effects. Conclusions: In a chronic ocular hypertensive rat model, topically applied WIN is an effective, nontoxic ocular hypotensive agent with no hemodynamic side-effects. This effect was predominantly CB1 receptor mediated, but some CB2 contribution could not be ruled out. [ABSTRACT FROM AUTHOR]

Ni4O4 cubanes [(μ3-L1O)NiCl(MeOH)]4 (1) and [(μ3-L2O)NiCl(H2O)]4 (2) (L1OH = 1-H-2-benzimidazolylmethanol, L2OH = 1-methyl-2-benzimidazolylmethanol) self-assemble from commercially available 1-H- and 1-methyl-2-benzimidazolylmethanol and NiCl2·6H2O in high yields under mild conditions. Both complexes were characterised spectroscopically and by X-ray crystallography. The cubanes oxidise water electrocatalytically to dioxygen at neutral pH in aqueous potassium phosphate buffer solutions. [ABSTRACT FROM AUTHOR]

Five neutral nickel(II) bimetallic models of the active site of [NiFe]‐hydrogenase supported by tridentate sulfur‐rich RNS2 ligands, were synthesized and tested as electrocatalysts for proton (H+) reduction. Complexes were classified according to the −NR substituent (1: 1‐methylpyrene; 2: 2‐methylthiophene; 3: phenyl) and as type a for those without bulky substituents and type b for the analogues with voluminous groups. Solid state structures were determined for three dimers, revealing [Ni2(μ‐SAr)2] frameworks, in which the two coordination planes around the Ni centres define a dihedral angle (θ) that is influenced by the substituents on the ligands (2 a: θ=180.0°, Ni ⋅⋅⋅ Ni=3.356 Å; 2 b: θ=98.55°, Ni ⋅⋅⋅ Ni=2.760 Å; 3 a: θ=107.32°, Ni ⋅⋅⋅ Ni=2.825 Å). Using CF3COOH as H+ source, 1 b and 2 b exhibit catalytic activity at −1.72 V (icat/ip≈2.40) and −1.80 V (icat/ip≈2.89) vs the ferrocenium/ferrocene couple (Fc+/Fc), respectively. In contrast, type a complexes were not viable catalysts. This behaviour suggests a relationship between the dimer conformation and its activity, due to a Ni ⋅⋅⋅ Ni cooperative effect, which is favoured in angular molecules and appears to assist during electrocatalytic H+ reduction. [ABSTRACT FROM AUTHOR]

Summary: This article addresses the plant‐model mismatch estimation problem for linear multiple‐input and multiple‐output systems operating under the dynamic matrix control (DMC) implementation of model predictive control. An autocovariance‐based method is proposed, aiming to identify parameter values that minimize the discrepancy between the theoretical autocovariance matrices derived from implementing the (explicit) DMC control law and the sampled autocovariance matrices calculated from operating data. We provide proof that the method results in unbiased estimates. A means for dealing with potential overfitting issues caused by the finite step response models used in DMC in practice is proposed. Several examples are presented to illustrated the theoretical developments. [ABSTRACT FROM AUTHOR]

[N,N‐bis(1‐methyl‐2‐benzimidazolyl)methyl‐N‐(bis‐2‐pyridylmethyl)amine] (L1) and [N,N‐bis(2‐quinolylmethyl)‐N‐bis(2‐pyridyl)methylamine] (L2) were employed to prepare CuII and CuI complexes for spectroscopic and structural characterization. [L1CuII(H2O)](NO3)2 and [L2CuII(NO3)]NO3 have Jahn–Teller distorted octahedral geometries and give rise to isotropic EPR spectra in frozen solution. [L1CuI(CH3CN)]OTf and [L2CuI(CH3CN)]OTf have distorted trigonal bipyramidal and tetrahedral solid‐state structures, respectively. The N‐donors display labile behavior in solution, based on variable‐temperature 1H NMR studies. Addition of trimethylamine N‐oxide (Me3NO) to solutions of [L1CuI(CH3CN)]OTf and [L2CuI(CH3CN)]OTf resulted in diamagnetic species tentatively assigned as the corresponding adducts upon replacement of coordinated acetonitrile, based on 1H NMR spectroscopy. Heating [L1CuI(CH3CN)]OTf to 50–60 °C in the presence of Me3NO resulted in its cupric analogue [L1CuII(CH3CN)]2+, as well as a small amount of 2‐dipyridylketone, along with other oxidation by‐products. In the case of [L2CuI(CH3CN)]OTf, the reaction with Me3NO resulted in the cupric complex bis(2‐quinolinecarboxamidato)copper(II), along with 2‐dipyridylketone as oxidation products. [ABSTRACT FROM AUTHOR]

This paper explores dimensionality reduction (DR) approaches for visualizing high dimensional data in chemical processes. Visualization provides powerful insight and process understanding in the industrial context, and accelerates process troubleshooting. A diverse array of existing, easy-to-use DR methods are evaluated in three case studies on large-scale industrial manufacturing plants. Supervised and unsupervised cases are presented with the objective of solving typical industrial problems related to unplanned events, plant performance improvement, and quality underperformance troubleshooting. For the unsupervised case, the evaluation aims to identify approaches that provide insight beyond those of PCA (Principal Component Analysis), and also examines quality metrics of the reduced (latent) space which characterize the degree of trust in the DR. UMAP (Uniform Manifold Approximation and Projection) outperforms other techniques, bringing new insights when comparing with other methods. For the supervised case, UMAP is combined with traditional variable selection methods, such as VIP (Variable Influence on Projection) weights from PLS-DA (Partial Least Squares Discriminant Analysis), in order to improve latent space visualization by increasing separation between classes. • Dimensionality reduction techniques are applied to three industrial case studies. • UMAP has outperformed other methods that solve unsupervised problems. • Combining UMAP with feature selection techniques improves latent space visualization. [ABSTRACT FROM AUTHOR]

This work presents the results obtained for a thioether derivative of bipyridine, (E,Z)-1-(4′-methyl-[2,2′-bipyridine]-4-yl)-N-(4(methylthio)phenyl)methanimine (4-mbpy-Bz-SMe), and its copper complex [CuII(4-mbpy-Bz-SMe)2]2+. Electronic spectra acquired at 183 K of the cuprous complex [CuI(4-mbpy-Bz-SMe)2]+ generated in situ indicated the formation of the peroxodicopper compound {[CuII(4-mbpy-Bz-SMe)2]2(μ-O22−)}2+. A gold electrode modified with [CuII(4-mbpy-Bz-SMe)2]2+ (Au/[Cu]) was fully characterized by SERS spectroscopy, electrochemistry and impedance spectroscopy thus showing adsorption occurs through the sulfur atom of the 4-mbpy-Bz-SMe moieties. DNA cleavage assays showed the copper complex, in solution and adsorbed on gold, degrades DNA if reducing conditions are maintained, i.e. ascorbic acid (H2AA) in solution or applied potentials more negative than 0.12 V vs. Ag/AgCl (CuI form). The electron paramagnetic resonance (EPR) spectra obtained for the electrolyzed solution (Eapl = −0.2 V, no H2O2) and for the solution containing [CuII(4-mbpy-Bz-SMe)2]2+ and H2O2 showed hydroxyl radical, HO˙, generation had occurred. The cyclic voltammograms obtained with H2AA in solution at Au/[CuII(4-mbpy-Bz-SMe)2]2+ as the working electrode showed a one-electron reaction leading to the ascorbyl radical (HA˙), which was detected by EPR. The current assigned to the electrode oxidation of HA˙ to AA decreased with the addition of catalase, a scavenger of H2O2, meaning peroxide is involved in the mechanism. [ABSTRACT FROM AUTHOR]

Two nickel complexes supported by tridentate NS2 ligands, [Ni2(κ‐N,S,S,S′‐NPh{CH2(MeC6H2R′)S}2)2] (1; R′=3,5‐(CF3)2C6H3) and [Ni2(κ‐N,S,S,S′‐NiBu{CH2C6H4S}2)2] (2), were prepared as bioinspired models of the active site of [NiFe] hydrogenases. The solid‐state structure of 1 reveals that the [Ni2(μ‐ArS)2] core is bent, with the planes of the nickel centers at a hinge angle of 81.3(5)°, whereas 2 shows a coplanar arrangement between both nickel(II) ions in the dimeric structure. Complex 1 electrocatalyzes proton reduction from CF3COOH at −1.93 (overpotential of 1.04 V, with icat/ip≈21.8) and −1.47 V (overpotential of 580 mV, with icat/ip≈5.9) versus the ferrocene/ferrocenium redox couple. The electrochemical behavior of 1 relative to that of 2 may be related to the bent [Ni2(μ‐ArS)2] core, which allows proximity of the two Ni⋅⋅⋅Ni centers at 2.730(8) Å; thus possibly favoring H+ reduction. In contrast, the planar [Ni2(μ‐ArS)2] core of 2 results in a Ni⋅⋅⋅Ni distance of 3.364(4) Å and is unstable in the presence of acid. [ABSTRACT FROM AUTHOR]

The MOF-type MIL-53(Al)-TDC was demonstrated to be an optimal adsorbent for H2S capture combining an unprecedented uptake at room temperature, excellent cyclability and low-temperature regeneration. [ABSTRACT FROM AUTHOR]

A set of sustainability attributes was estimated in Western Guatemala by characterizing 20 small-scale farming families with the aim of exploring food security- and climate resilience-related conditions. Solidarity-based economies spawn a stronger social network among agroecological farms. Gender roles in agroecology-adopting families seem to be moving to a more balanced scenario. Differences between agroecology-based and semi-conventional farmers suggest that shares of commercialized produce, gross agricultural income, and plant diversity are significantly higher and thus more resilient in the former. Challenges to agroecological adoption, however, include limited public infrastructure, dearth of supporting policies, and external threats posed by utility-inspired economic agents. [ABSTRACT FROM AUTHOR]