L Complexes Research Articles

Phraseological sophistication as a multidimensional construct

Abstract Since Paquot (2019), several unresolved issues have persisted regarding the operationalization of phraseological sophistication in L2 complexity research. One of the most crucial concerns relates to the extent to which the commonly used measures of phraseological sophistication (MI scores) fully represent the intended construct. In this study, we draw upon insights from L2 phraseological research to reexamine the conceptualization and operationalization of phraseological sophistication. We conduct new analyses on the learner corpus used in Paquot (2019), using alternative operationalizations of phraseological sophistication that represent different dimensions of sophistication (based on the register specificity of word combinations and their frequency). Results show that measures representing the dimensions of association (MI scores) and register specificity (ratios of academic collocations) correlate with each other. Frequency-based measures, however, pattern very differently, which we attribute to some issues in the way we operationalized frequency of co-occurrence.

Interactions between task complexity, task repetition, and task motivation in L2 writing

This study explores the interplay between task repetition and task motivation in second language (L2) writing, specifically focusing on syntactic complexity, accuracy, and lexical complexity (CAL). Aligning with Dörnyei’s call to balance cognitive and affective factors in task-based language teaching (TBLT), the research involved 100 advanced mid-level learners of English as a second language (ESL) aged between 18 and 20 years. Participants completed both simple and complex argumentative writing tasks in a counterbalanced order, with a one-week interval between tasks. A perception questionnaire was administered immediately after each task performance to validate cognitive task complexity manipulations. Subsequently, participants repeated the same tasks with the same time interval, complemented by the completion of a task motivation questionnaire after each task. Written essays were collected and analysed for CAL measures. Employing a multivariate multilevel approach, the results were triangulated with self-report data. Findings indicate that task repetition significantly impacted CAL in L2 writing, with a positive moderation effect by task complexity. Additionally, task motivation enhanced syntactic complexity in both simple and complex tasks, with negligible effects on accuracy. Notably, task motivation exerted a more substantial influence on students’ repeated task performance concerning lexical complexity. The study’s results offer theoretical and pedagogical insights for TBLT researchers and L2 writing practitioners.

Introducing Phosphate Ester into DAPhen by Propyl Enhanced the Selectivity for UO22+ over Th4.

A new type of phenanthroline carboxamide(DAPhen)-phosphate ester ligand (L1/L2) was synthesized for the selective separation of U(VI) over Th(IV). Liquid-liquid extraction experiments showed that the introduction of phosphate ester could increase the extraction ability of ligands for U(VI), especially L2, which showed high selectivity for the separation of U(VI) over Th(IV). The slope analysis indicated that L1 could form 1:1 and 1:2 complexes with U(VI) and 1:1 complexes with Th(IV). NMR titration revealed that the DAPhen unit of ligands combined with one U(VI) to form 1:1 complexes, and then the phosphate ester unit of the 1:1 complexes further combined with another U(VI) to form 1:2 complexes. Ligands provide only the DAPhen unit to Th(IV) to form 1:1 complexes. The crystal structures found 1:2 complexes of L1 and U(VI), 1:1 complexes of L2 and U(VI), and 1:1 complexes of L1 and Th(IV). The larger stability constant (log β) of the 1:1 complexes of L2 with U(VI) than that of the 1:1 complexes of L1 with U(VI) showed that the binding ability of U(VI) with the DAPhen unit of L2 is stronger than that of U(VI) with the DAPhen unit of L1. This study provides new ideas for designing extractants with excellent properties.

EXPRESIÓN EMBRIOGÉNICA DIRECTA EN Agave cupreata

<p><strong>Background:</strong> <em>Agave cupreata</em> is a specie that can only reproduce by seeds and could take up to 15 years until flowering, placing it at risk of extinction due to its agroindustrial exploitation to produce mezcal. <strong>Objective:</strong> To evaluate the type of explant, the vitamin complex and 2,4-D concentrations on the direct embryogenic response. <strong>Methodology:</strong> Explants of leaf, root and stem sections were evaluated. Also, the vitamins MS (Murashige and Skoog, 1962) and L2 (Phillips and Collins, 1979), five concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D), (0.0, 0.1, 0.3, 0.6 and 0.9 mg L<sup>-1</sup>) and six concentrations of indole-3-acetic acid (IAA), (0.0, 0.1, 0.5, 1.0, 2.0 and 3.0 mg L<sup>-1</sup>) were assayed for the expression of somatic embryos directly. <strong>Results: </strong>The leaf explant, the vitamin L2 complex, and the concentration of 0.9 mg L<sup>-1</sup> of 2,4-D and 0.5 mg L<sup>-1</sup> of IAA turned out to be the most efficient for the formation of pro-embryogenic masses and the expression of direct somatic embryos in the globular state. <strong>Implications:</strong> These results lay the groundwork for the future regeneration of <em>A. cupreata</em> plants via direct somatic embryogenesis, potentially facilitating their conservation and mass propagation. This contributes to the sustainability of mezcal; boosts the local economy, preserves biodiversity, and ensures the continued production of this endangered species. <strong>Conclusions:</strong> For the first time, the successful expression of somatic embryos directly from <em>A. cupreata</em> explants was evidenced.</p>

A new insight on the effects of Schiff Base Iron (III) complexes in breast cancer cells for clinical radiotherapy

PurposeBreast cancer is a significant global health concern, and researchers strive to enhance radiotherapy outcomes while minimizing the side effects. Schiff Base Iron (III) Complexes are one of the prospective elements that can be used as radiosensitizer or radioprotective agents in cancer radiotherapy. This study investigates the potential effects of Schiff base (ligand 2; L2) with Fe(III) in MCF-7 breast cancer cells under clinical radiotherapy treatment. MethodsThe effects of the Schiff Base Iron (III) Complexes were measured using clonogenic assay with MCF-7 breast cancer cells. The cells were irradiated with megavoltage 6 MV photon, 6 MeV electron and high dose rate (HDR) brachytherapy with 192Ir source at different doses. Intercellular localization of Fe(III)-L2 complexes and antioxidant activities were also investigated. ResultsThe Fe(III)-L2 complexes were observed to be internalized by cellular nuclei without any effects on the cells. Interestingly, the Fe(III)-L2 complexes indicate radioprotective effects which provide intriguing insight towards application of metal ions complexes as radioprotector in cancer radiotherapy. The Fe(III)-L2 complexes also exhibit scavenging activities of free radical which further proved the antioxidative properties and radioprotective effects. ConclusionThe Fe(III)-L2 complexes show the radioprotective effects and antioxidant properties in MCF-7 cells, particularly for HDR brachytherapy. The findings suggest potential applications of the Fe(III)-L2 complexes as radioprotector agents in clinical radiotherapy.

Synthesis and Biological Evaluation of Novel Imidazolone - Thiabendazole-Based Metal Complexes.

Thiabendazole-based metal complexes are attracting interest due to their special antimicrobial activities. The current investigation describes the preparation of ligand L1 and its metal complexes [M (C26H17N5OS) Cl2] M = Co, Ni, Cu and Zn. Mass, 1 H-NMR, IR, and UV were used to characterize these compounds. L1 exhibited the highest potency towards many bacteria. It shows the maximum zone of inhibition as compared to any other ligand. Thus, the antibacterial potency of L1 is better as compared to standard drugs. Imidazolone-TBZ ligands L1 are also more susceptible to some bacteria and also show antifungal potency against Pseudomonas aeruginosa. The significance of such work triggered the possibility that these ligands L1 and metal complexes can be efficacious drugs against bacterial and fungal species that could be advantageous in designing powerful antibacterial and antifungal compounds for medicinal use. All these synthesized compounds are in addition to the library of heterocyclic compounds.

The The correlations between the average semester growth rates of syntactic and lexical complexity in L2 writing development at secondary school

The article is devoted to the development of language complexity in a relatively under-researched area of adolescent writing from the point of view of Complex Dynamic Systems Theory (CDST). It describes the second part of a panel study which aimed to examine the relationships among the average semester growth rates (ASGRs) of specific measures of syntactic and lexical complexity within and between these two subsystems in writing in English as a foreign language at the secondary school level. The study involved the analysis of The Written English Developmental Corpus of Polish Learners (WEDCPL). The corpus, which comprises over 1900 essays, was created on the basis of 21 repeated measurements conducted in a group of 100 secondary school learners during a period of three years. With respect to the specific measures of syntactic and lexical complexity, the study indicated that nominalization developed faster than subordination and coordination, and that lexical variation developed faster than lexical density and sophistication per semester. Moreover, the relationships between the ASGRs of both syntactic and lexical measures were more supportive within than between the subsystems. The main pedagogical implication for English language teachers refers to fostering more coordinated development of language complexity at secondary school in the EFL context.

Novel copper-drugs bearing dipodal bis-mercaptobenzimidazoles: Synthesis, crystal structures, in vitro biological activities, DNA binding, DFT calculations and molecular docking

Three novel copper(II) complexes, 1–3, bearing dipodal bis-mercaptobenzimidazole derivatives based on ortho-, meta- or para-xylene (L1, L2, and L3) were successfully prepared and characterized by using various spectral techniques, including elemental analysis, FT-IR, 1H NMR, and UV–Vis spectroscopy, LC-MS spectrometry and TGA. The analysis revealed that the ligand/metal molar ratio in all copper(II) complexes is 1:1 and the ligand coordinates as a neutral N-donor onto metal center. Additionally, the crystal structures of L1, L2, L3, and copper(II) complex 2 were determined using single crystal X-ray diffraction (SC-XRD) analysis. Copper(II) complexes 1–3 displayed significant stability at pH range of 4–10. The antibacterial effect of ligands and complexes was tested against both gram-negative (Escherichia coli, E. coli ATCC 25922 PTCC 1399) and gram-positive (Staphylococcus aureus, S. aureus ATCC 6538 PTCC 1112) bacterial strains. It should be noted that the complexes showed enhanced antibacterial activity (up to 99 %) when compared to their free ligands. The in vitro studies of all synthesized compounds consisted of testing them against the human colorectal carcinoma cancer cell line (HCT-116) using the MTT assay. The findings revealed that the copper(II) complexes exhibited lower CC50 values (CC50 ranging from 0.045 mM to 0.135 mM) compared to their corresponding ligands (CC50 ranging from 0.150 mM to 0.240 mM) and carboplatin (CC50 = 0.165 mM), indicating higher anticancer activity of the complexes. Additionally, DAPI staining and fluorescence spectroscopy (at three different temperatures) were performed to further examine the impact of complexes 1–3 on inducing apoptosis and to explore their interaction with DNA, respectively. The results revealed a dynamic quenching mechanism, with hydrophobic forces playing a dominant role in the binding process. The viscosity measurements indicated that all complexes could interact in a groove binding manner with DNA. Density functional theory (DFT) calculations were employed to support the structural and vibrational studies and to predict the chemical reactivity. Docking simulations were conducted to evaluate their behavior of the synthesized compounds towards DNA (PDB: 1BNA). These results suggested that various elements, including NH groups, imidazole rings, thioetheric sulfur atom and sulfate moieties of ligands and complexes, are involved in groove binding with DNA.

Transcranial photobiomodulation on the left inferior frontal gyrus enhances Mandarin Chinese L1 and L2 complex sentence processing performances

This study investigated the causal enhancing effect of transcranial photobiomodulation (tPBM) over the left inferior frontal gyrus (LIFG) on syntactically complex Mandarin Chinese first language (L1) and second language (L2) sentence processing performances. Two (L1 and L2) groups of participants (thirty per group) were recruited to receive the double-blind, sham-controlled tPBM intervention via LIFG, followed by the sentence processing, the verbal working memory (WM), and the visual WM tasks. Results revealed a consistent pattern for both groups: (a) tPBM enhanced sentence processing performance but not verbal WM for linear processing of unstructured sequences and visual WM performances; (b) Participants with lower sentence processing performances under sham tPBM benefited more from active tPBM. Taken together, the current study substantiated that tPBM enhanced L1 and L2 sentence processing, and would serve as a promising and cost-effective noninvasive brain stimulation (NIBS) tool for future applications on upregulating the human language faculty.

Anion-binding-induced selective aggregation and self-degradation: Influence of positional isomerism on the anion selectivity and mode of binding of an imine-based receptor

Imine based positional isomers (8E)-N-(4-((E)-(perfluorophenylimino)methyl)benzylidene)-2,3,4,5,6-pentafluorobenzenamine, L and (10E)-N-(3-(E-Perfluorophenylimino)methyl)benzylidene)-2,3,4,5,6-pentafluorobenzenamine, L1 have been designed, and synthesized by functionalizing two electron deficient aromatic moieties at the para–para’/ortho-ortho’ positions in the phenyl core of the L and L1 respectively. The responses of L and L1 towards various anionic species are examined. The positional isomers L and L1 differs not only by showing distinguishable color change upon addition of anions but also differentiates themselves by the way of self-assembling together upon binding with cyanide anion. The naked-eye colorimetric experiments, UV–Vis, Nuclear Magnetic Resonance, and Infra-Red spectroscopic analyses reveal that the isomer L binds fluoride anion through 2:1 stoichiometry ratio. Unlike fluoride complex, the isomer L form aggregates while binding with cyanide ion. On the other hand, isomer L1 does not show any instant color change upon additions of any anion. Interestingly, after thirty minutes, only the color of the cyanide complex is turned into dark brown. While analyzing the spectroscopic results of cyanide complex of L1, it is found that the cyanide complex begins to decompose and finally it is completely decomposed within 30 min. This unprecedented phenomenon about the colorimetric sensing of cyanide and destruction of cyanide complex with respect to time has not been reported in the literature yet. To the best of our knowledge this is the first example of study of sensing controlling the selectivity, mode of binding, self-aggregating and degradation properties of anionic complexes under the influence of positional isomeric effects. This present investigation provides simple and effective strategy to construct the sensor molecules with tunable binding properties in terms of easy to prepare as well as easy to use as a colorimetric sensor._____________________________________________________________________________________________________

Mapping the associations among task complexity, emotionality, and linguistic complexity in L2 writing

This study explored the relationship between task complexity, textual emotionality, and linguistic complexity in second language (L2) writing. Fifty-eight L2 English learners performed simple and complex versions of an argumentative writing task manipulated along with resource-­directing variables. The essays were first analysed for textual emotionality with sentiment analysis and then examined using a set of lexical and syntactic complexity and cohesiveness indices. Regarding emotionality, the complex task elicited more positive and negative emotions than the simple task. Further, the complex task led to greater lexical complexity and cohesiveness than the simple task, but the two tasks were not statistically different from each other in terms of syntactic complexity features. Varied patterns of correlations were observed between emotionality metrics and indices of different dimensions of linguistic complexity in the two tasks. Our findings focusing on the intersections of cognitive, socio-emotive, and linguistic components suggest that different task complexity manipulations could generate varying cognitive demands, affecting L2 written production. These findings provide theoretical and pedagogical implications for TBLT researchers and L2 writing practitioners.

Computational Exploration of Potential Pharmacological Inhibitors Targeting the Envelope Protein of the Kyasanur Forest Disease Virus.

The limitations of the current vaccination strategy for the Kyasanur Forest Disease virus (KFDV) underscore the critical need for effective antiviral treatments, highlighting the crucial importance of exploring novel therapeutic approaches through in silico drug design. Kyasanur Forest Disease, caused by KFDV, is a tick-borne disease with a mortality of 3-5% and an annual incidence of 400 to 500 cases. In the early stage of infection, the envelope protein plays a crucial role by facilitating host-virus interactions. The objective of this research is to develop effective antivirals targeting the envelope protein to disrupt the virus-host interaction. In line with this, the 3D structure of the envelope protein was modeled and refined through molecular modeling techniques, and subsequently, ligands were designed via de novo design and pharmacophore screening, yielding 12 potential hits followed by ADMET analysis. The top five candidates underwent geometry optimization and molecular docking. Notably, compounds L4 (SA28) and L3 (CNP0247967) are predicted to have significant binding affinities of -8.91 and -7.58 kcal/mol, respectively, toward the envelope protein, based on computational models. Both compounds demonstrated stability during 200 ns molecular dynamics simulations, and the MM-GBSA binding free-energy values were -85.26 ± 4.63 kcal/mol and -66.60 ± 2.92 kcal/mol for the envelope protein L3 and L4 complexes, respectively. Based on the computational prediction, it is suggested that both compounds have potential as drug candidates for controlling host-virus interactions by targeting the envelope protein. Further validation through in-vitro assays would complement the findings of the present in silico investigations.

Withdrawn: Exploring the associations among task complexity, task motivation, task engagement, and linguistic complexity in L2 writing

Withdrawal: Mahmoud Abdi Tabari, Bronson Hui, Exploring the associations among task complexity, task motivation, task engagement, and linguistic complexity in L2 writing, The Modern Language Journal, 29th April 2024, (https://onlinelibrary.wiley.com/doi/10.1111/modl.12921).The above article, published online on 29th April 2024, on Wiley Online Library (https://onlinelibrary.wiley.com/doi/10.1111/modl.12921), has been withdrawn by agreement among the authors, the journal Editor in Chief, Marta Antón, the National Federation of Modern Language Teachers' Associations, and John Wiley and Sons, Ltd. The withdrawal has been agreed because the Open Access Agreement was not correctly signed.

Micelle encapsulated luminescent iridium(III)(ppy)2L complexes: Photophysics, photocytotoxic activity in HeLa cells and morphological confocal microscopy imaging in C. flavicans M. larva and L. sativum L. plant

Luminescent cyclometallated Ir(III) complexes are multi-modal tools for biological applications. Unfortunately, their potential as imaging and therapeutic agents is often limited by their very low solubility in water and most biological media. Especially the “solubility problem” of Ir(III) complexes influence the imaging of live multicellular animal and plant species in their natural water-abundant habitats. Herein we bypass this difficulty by encapsulation of the two brightly luminescent iridium(III)(ppy)2L1 or L2 (ppy = 2-phenylpyridine, L1 = 2-phenylpyridine-4-amine, L2 = 2-phenylpyridine-4-dimethylamine) complexes into pluronic F-127 block copolymer to form water soluble Ir-loaded micelles. These dye-loaded micelles are indeed rapidly internalized by the cells and no antiproliferative activity is observed in darkness. In contrast, 430 nm light irradiation of the same cells triggered singlet oxygen generation and oxidative stress what resulted in strong lethal effects. The water-soluble Ir-containing micelles could also be used as luminescent probes for studing complex multicellular organisms such as alive water-living phantom midge larva of Chaoborus flavicans M. and Lepidium sativum L. plant which elude of imaging with poorly-water soluble Ir(III) complexes. Iridium-containing micelles localized inside the digestive system and hydrostatic organs of larvae as well as in water-conducting tissues of the plant. Furthermore, although to a lesser extent, this new strategy of encapsulation of the Ir complexes allowed to circumvent the bacterial cell wall barrier and, thus, to penetrate inside S. aureus and E. coli cells. These results provide a reliable strategy for development of new theranostic agents and imaging probes.

Exo- or endo-1H-pyrazole metal coordination modulated by the polyamine chain length in [1 + 1] condensation azamacrocycles. Binuclear complexes with remarkable SOD activity.

The Cu2+ complexes of three [1 + 1] azacyclophane macrocycles having the 1H-pyrazole ring as the spacer and the pentaamine 1,5,8,11,15-pentaazadecane (L1) or hexaamines 1,5,8,12,15,19-hexaazanonadecane (L2) and 1,5,9,13,17,21-hexaazaheneicosane (L3) as bridges show endo- coordination of the pyrazolate bridge giving rise to discrete monomeric species. Previously reported pyrazolacyclophanes evidenced, however, exo-coordination with the formation of dimeric species of 2 : 2, 3 : 2 or even 4 : 2 Cu2+ : L stoichiometry. The complexes have been characterized in solution using potentiometric studies, UV-Vis spectroscopy, paramagnetic NMR, cyclic voltammetry and mass spectrometry. The measurements show that all three ligands have as many protonation steps in water as secondary amines are in the bridge, while they are able to form both mono- and binuclear Cu2+ species. The crystal structures of the complexes [Cu(HL1)Br]Br(1+x)(ClO4)(1-x)·yH2O (1) and [Cu2(H-1L2)Cl(ClO4)](ClO4)·H2O·C2H5OH (2) have been solved by X-ray diffraction studies. In 1 the metal ion lies at one side of the macrocyclic cavity being coordinated by one nitrogen of the pyrazolate moiety and the three consecutive nitrogen atoms of the polyamine bridge. The other nitrogen of the pyrazole ring is hydrogen-bonded to an amine group. In 2 the two metal ions are interconnected by a pyrazolate bis(monodentate) moiety and complete their coordination spheres with three amines and either a bromide or a perchlorate anion, which occupy the axial positions of distorted square pyramid geometries. Paramagnetic NMR studies of the binuclear complexes confirm the coordination pattern observed in the crystal structures. Cyclic voltamperommetry data show potentials within the adequate range to exhibit superoxide dismutase (SOD) activity. The IC50 values calculated by McCord-Fridovich enzymatic assays show that the binuclear Cu2+ complexes of L2 and L3 have SOD activities that rank amongst the highest ones reported so far.

Computational study of core modified dipyriamethyrin for the competitive complexation of Am3+/Cm3+ from their trichlorides.

In the process of handling and storage of radioactive actinides it is essential to selectively sequester the minor actinides, such as Am and Cm, through a competitive complexation process. Herein we computationally designed two core modified ligands (L21- and L3) through systematic oxygen substitution at the NH sites of dipyriamethyrin (L1_2H), a hexadentate expanded porphyrin, and studied their competitive complexation towards trivalent actinides (An = Am/Cm) from their trichlorides using density functional theory (DFT). We observed shorter An-N bonds and longer An-O bonds in complexes based on core modified ligands (L21- and L3). The An-Cl bond length increases with increasing axial coordination number (i.e., from L12- to L3) to accommodate the ligands. All the bonds were identified to be electrostatic in nature. L12- exhibits shorter bonds and larger bond orders on complexing with Am than with Cm. On moving from complexes of L21- to L3, the An-N bond lengths are shortened, while An-O bond lengths become larger. Between the complexes of Am and Cm, there is marginal difference in their bond distances with L21- and L3. Charge analysis shows ligand to metal charge transfer during coordination, with back-donation from An to N/O and Cl. The calculated spin-density analysis indicates that An remains in its trivalent oxidation state on complexation, while orbital occupation analysis shows that the 5f and 6d orbitals are involved in bonding; this was confirmed by molecular orbital (MO) analysis that shows the complexes of L21- and L3 to exhibit higher degeneracy in their overlapping MOs. Further, the energy decomposition analysis (EDA) confirms that all ionic bonds are primarily due to electrostatic contributions, where the orbital contributions increase from L12- to L3 complexes and maximum covalency was observed in Cm complexes due to the energy matching between the 5f orbitals of Cm and the 2p orbitals of N and Cl, compared to Am. To confirm the competitiveness in the complexation of the ligand towards Am vs. Cm, the thermodynamic parameters were analysed for the ligand and metal substitution reactions. L12- shows more affinity towards Am than Cm, while L21- and L3 prefer Cm.

Hexanuclear Ln6 L6 Complex Formation by Using an Unsymmetric Ligand.

Multinuclear, self-assembled lanthanide complexes present clear opportunities as sensors and imaging agents. Despite the widely acknowledged potential of this class of supramolecule, synthetic and characterization challenges continue to limit systematic studies into their self-assembly restricting the number and variety of lanthanide architectures reported relative to their transition metal counterparts. Here we present the first study evaluating the effect of ligand backbone symmetry on multinuclear lanthanide complex self-assembly. Replacement of a symmetric ethylene linker with an unsymmetric amide at the center of a homoditopic ligand governs formation of an unusual Ln6 L6 complex with coordinatively unsaturated metal centers. The choice of triflate as a counterion, and the effect of ionic radii are shown to be critical for formation of the Ln6 L6 complex. The atypical Ln6 L6 architecture is characterized using a combination of mass spectrometry, luminescence, DOSY NMR and EPR spectroscopy measurements. Luminescence experiments support clear differences between comparable Eu6 L6 and Eu2 L3 complexes, with relatively short luminescent lifetimes and low quantum yields observed for the Eu6 L6 structure indicative of non-radiative decay processes. Synthesis of the Gd6 L6 analogue allows three distinct Gd⋯Gd distance measurements to be extracted using homo-RIDME EPR experiments.

Development of clausal and phrasal complexity in L2 writing: A case of argumentative essays of Korean college students

This study aims to estimate the developmental trajectory of grammatical complexity for L2 writers by investigating the extent to which clausal and phrasal complexity is associated with L2 writing proficiency. The corpus used in this study contained 234 argumentative essays of first-year Korean college students at three proficiency levels. The five clausal and four phrasal features were extracted from the tagged corpus to count the frequency of each complexity feature. Our findings demonstrated an association between writing proficiency and clausal and phrasal complexity. Especially noteworthy was that the main source of complexity at each proficiency level (i.e., finite adverbial clauses, WH relative clauses, of phrases as nominal postmodifiers) showed a gradual increase in complexity in terms of two parameters: structural type and syntactic function. A qualitative follow-up analysis provided a detailed description of differences among developmental levels, especially with respect to the lexical associations of particular complexity features. Pedagogical implications are for using empirically derived developmental stages in creating detailed rating scale descriptors and providing more customized writing courses accordingly.

An insight into the cytotoxic, antimicrobial, antioxidant, and biocontrol perspective of novel Iron(III) complexes of substituted benzimidazoles: Inhibition kinetics and molecular simulations

Mononuclear complexes [FeCl3L2(OH2)] (L = L1, L2) were designed and synthesized by combining FeCl3 with 2-(3′-Aminophenylbenzimidazole) (L1) and 2-[(3′-N-Salicylidinephenyl)benzimidazole] (L2) and were characterized by physico-analytical strategies. The redox properties of the complexes were disclosed by the cyclic voltammetric method. Further, the interactions of complexes with proteins were studied by performing molecular docking engaging protein models of common cancer therapeutic targets to foresee their affinity to bind to these proteins. The complexes evidenced better protein-ligand docking (−8.4 and −9.0 kcal mol−1) and higher binding energies than their ligands. However, the L1 complex displayed improved binding free energy (−33.576 ± 1.01 kcal mol−1) compared to the other complexes and individual ligands. These compounds were screened for in vitro cytotoxic assays against triple-negative breast cancer cell lines (MDA-MB-468 cells), anti-inflammatory, antimicrobial, and antioxidant properties. The in vitro study complemented the in silico assay; therefore, these compounds may be a viable choice for expanding anticancer therapy. Additionally, the L2 showed better biocontrol activity owing to the enhanced growth of Trichoderma and inhibited the growth of Fusarium oxysporum. Communicated by Ramaswamy H. Sarma

Cerium(IV) Nitrate Complexes With Bidentate Phosphine Oxides

AbstractThe reactions between ceric ammonium nitrate, (NH4)2Ce(NO3)6, (CAN) and the bidentate phosphine oxides, 4,5‐bis(diphenylphosphine oxide)‐9,9‐dimethylxanthene (L1), oxydi‐2,1‐phenylene bis(diphenylphosphine dioxide) (L2), 1,2‐bis(diphenylphosphino)ethane dioxide (L3) and 1,4‐bis(diphenylphosphino)butane dioxide, L4 have been investigated. The crystal structures of the molecular Ce(NO3)4L1 (1), and ionic [Ce(NO3)3L32][NO3]⋅CHCl3 (3), [Ce(NO3)3L32][NO3] (4) and the polymeric [Ce(NO3)3L41.5] [NO3] (5) and the cerium(III) complex [Ce(NO3)2L12][NO3] (2) are reported. The thermal stability of the complexes has been examined by thermogravimetry with the gaseous decomposition products analysed by infrared spectroscopy. Evolution of CO2 is found for both Ce(III) and Ce(IV) complexes with the later also forming NO2. The formation of the complexes in solution has been studied by 31P NMR spectroscopy and further complexes [Ce(NO3)3L12]+[NO3]− and [Ce(NO3)2L13]2+2[NO3]− identified in CD3CN solution. The complex (1) exists as a single molecular species in solution and is stable in dichloromethane whilst (3) decomposes on standing in both CD2Cl2 and CD3CN to Ce(III) containing species. Complexes of L2 have been identified by solution 31P NMR spectroscopy and these decompose in solution to give Ce(NO3)3L22. This study represents the first structural characterisations of Ce(IV) complexes with bidentate phosphine oxides.