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Flow NMR is an expanding analytical approach with applications that include in-line analysis for process control and optimisation, and real-time reaction monitoring. The samples monitored by flow NMR are typically mixtures that yield complex 1D 1 H spectra. "Pure shift" NMR is a powerful approach to simplifying 1 H NMR spectra, but its standard implementation is not compatible with continuous flow because of interference between sample motion and the position-dependent spin manipulations that are required in pure shift NMR. Here we show that pure shift NMR spectra can be successfully collected for continuously flowing samples, thanks to an adapted acquisition scheme, robust solvent suppression, and a velocity-compensation strategy. The resulting method is used to collect ultrahigh resolution reaction monitoring data. Pure shift NMR spectra are expected to benefit many applications of flow NMR., (© 2024 The Author(s). Chemistry - A European Journal published by Wiley-VCH GmbH.)

The effect of unprecedented climate change conditions on the environment has attracted the attention of experts from various disciplines who wish to predict its evolution. This is due to its interaction with population health and people's quality of life. The emergence of vector-borne diseases (VBD) in Europe, particularly caused by invasive mosquitoes, has resulted in autochthonous transmission of Dengue and Chikungunya virus cases. In this contribution, we delve into the significant decline in the population of tiger mosquitoes and the noticeable reduction in their size, related to the changes that occur often in years with low rainfall and high temperatures during the summer months. This change can be traced to the morphology of the species, which has been analysed in this work and related to the possible enhanced transmission efficiency and susceptibility of vectors to VBD dissemination. Due to the greater susceptibility to pathogen replication and subsequent transmission of the pathogens to a host during blood feeding, these morphologically distinct species relatively seem to be an efficient vector. The relationship between the sizes of studied mosquitoes and rainfall levels requires more research by mathematical epidemiologists., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Importance: There are suggestions that school pressure may be stressful and a factor in child and adolescent mental health disturbances, but data about this association are scarce and inconclusive., Objective: To assess whether varying degrees of school interruption were associated with changes in emergency department (ED) psychiatric visits of children and adolescents before and after the COVID-19 outbreak., Design, Setting, and Participants: A cross-sectional observational study was conducted at 9 urban university hospitals in Italy. All ED visits from January 1, 2018, to December 31, 2021, for psychiatric reasons of patients younger than 18 years were examined for demographic characteristics and type of psychopathologic factors. Data analysis was conducted from July 1 to August 31, 2023., Exposure: The disruption in the usual succession of school and holiday periods brought on by the COVID-19 pandemic at different times and with various degrees of intensity., Main Outcomes and Measures: Total number of pediatric ED visits, psychiatric ED visits, and psychiatric ED visits categorized by specific reasons (eg, psychomotor agitation, suicide ideation [SI] or suicide attempt [SA], and eating disorders) on a weekly basis., Results: A total of 13 014 psychiatric ED visits (1.3% of all pediatric ED visits) were recorded (63.2% females; mean [SD] age, 13.8 [3.8] years). The number of ED psychiatric visits increased over time (incidence rate ratio [IRR], 1.19; 95% CI, 1.16-1.22 for each year). Significant increases in ED visits were observed for eating disorders (294.8%), SI (297.8%), and SA (249.1%). School opening, but not social lockdown restriction, was associated with an increase in the number of ED psychiatric visits (IRR, 1.29; 95% CI, 1.23-1.34), which was evident for females and for SI with SA. Socioeconomic status was associated with an increase in psychiatric visits for males (IRR, 1.12; 95% CI, 1.04-1.20) but not females (IRR, 1.04; 95% CI, 0.98-1.10)., Conclusions and Relevance: In this study, school opening was associated with an increased incidence of acute psychiatric emergencies among children and adolescents, suggesting that school can be a substantial source of stress with acute mental health implications.

Selective NMR experiments provide rapid access to important structural information, and are essential to tackle the analysis of large molecules and complex mixtures. Single-scan ultraselective experiments are particularly useful, as they can rapidly select signals that overlap with other signals. Here, we describe a novel type of single-scan ultraselective NMR experiments that is robust against the effects of translational molecular diffusion, and thus make it possible to improve significantly the sensitivity of the experiment. This will largely broaden the applicability of this powerful class of experiments., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Flow NMR is a powerful tool to monitor chemical reactions under realistic conditions. Here, we describe ultrafast (UF) 2D NMR schemes that make it possible to acquire broadband homonuclear 2D NMR spectra in 90 seconds or less for a continuously flowing sample. An interleaved acquisition strategy is used to address the spectral width limitation of UF 2D NMR. We show how, for a flowing sample, the use of a transverse axis for spatial encoding makes it possible to achieve the very high scan-to-scan stability required for interleaved acquisition. We also describe an optimised solvent suppression strategy that is effective for interleaved acquisition in continuous flow. These developments open the way to online monitoring with flow 2D NMR at high time resolution, as we illustrate with the monitoring of an organocatalysed condensation reaction.

Evidence suggests that adolescents respond positively to simple, early interventions, including psychosocial support and educational interventions, even when offered in non-clinical settings. Cinematherapy can help manage life challenges, develop new skills, increase awareness, and offer new ways of thinking about specific problems. This pilot trial was conducted in Italy, aiming to investigate the effects of a six-week filmmaking course on the psychological well-being of adolescents (N = 52) with emotional/behavioural problems and neurodevelopmental disorders. At the end of the project, most participants showed improvements mostly in social skills, such as social cognition ( p = 0.049), communication ( p = 0.009), and motivation ( p = 0.03), detected using the SRS Social Responsiveness Scale. In addition, social awareness ( p = 0.001) increased in all patients. Statistically significant differences resulted in four sub-scales of Youth Self-Report Scale: withdrawn/depressed ( p = 0.007), social problems ( p = 0.003), thought problems ( p < 0.001), and rule-breaking behaviour ( p = 0.03); these results showed a decrease in emotional and behavioural problems. This study is an innovative therapeutic and educational approach based on the filmmaking art. This research can offer an empirical basis for the effectiveness of alternative therapeutic tools in child and adolescent psychiatric disorders. At the same time, it can be replicated in broader contexts (e.g., school and communities) to promote children's psychological well-being.

Recent clinical studies, in both children/adolescents and adults, have shown the extreme neuropsychological heterogeneity of attention-deficit hyperactivity disorder (ADHD): specific neuropsychological deficits have been found only in a minority of individuals, with no direct correlation between discrete cognitive performances and the trajectory of clinical symptoms. Deficits in specific neuropsychological functions may be common in ADHD, but nevertheless no cognitive or neuropsychological profile may fully explain the disorder. Sex differences in the ADHD presentation, both at a neuropsychological and clinical level, also contribute to this clinical and neuropsychological heterogeneity. At a neuropsychological level, females with ADHD may show greater working memory problems, poorer vocabulary skills and worse visual spatial reasoning. Structural and functional imaging study also show discrete differences across sex; however, the great majority of clinical studies mainly or exclusively include male participants with insufficient data to draw firm conclusions on sex differences within the disorder. Here, we report the recent literature data, discussing still open research questions about the clinical presentation, neuroimaging findings, and neuropsychological functioning in ADHD with a focus on the impact of sex differences-a deeper insight in these unresolved issues may have relevant clinical and therapeutic implications for tailored, effective, and long-lasting interventions., (© 2022 The Authors. Journal of Neuroscience Research published by Wiley Periodicals LLC.)

This work demonstrates the in-line monitoring of a flow photochemical reaction using 1D and ultrafast 2D NMR methods at high magnetic field. The reaction mixture exiting the flow reactor is flown through the NMR spectrometer and directly analyzed. In the case of simple substrates, suitable information can be obtained through 1D 1 H spectra, but for molecules of higher complexity the use of 2D experiments is key to address signal overlaps and assignment issues. Here we show the usefulness of ultrafast 2D COSY experiments acquired in 70 s or less, for the in-line monitoring of photochemical reactions, and the possibility to obtain reliable quantitative information. This is a powerful framework to, for example, efficiently screen reaction conditions., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

In this work, the ability of several bis-viologen axles to thread a series of heteroditopic tris(N-phenylureido)calix[6]arene wheels to give interwoven supramolecular complexes to the [3]pseudorotaxane type was studied. The unidirectionality of the threading process inside these nonsymmetric wheels allows the formation of highly preorganised [3]pseudorotaxane and [3]rotaxane species in which the macrocycles phenylureido moieties, functionalised with either ester, carboxylic, or hydroxymethyl groups, are facing each other. As verified by NMR and semiempirical computational studies, these latter compounds possess the correct spatial arrangement of their subcomponents, which could lead, in principle, upon proper bridging reaction, to the realisation of upper-to-upper molecular capsules that are based on calix[6]arene derivatives.

An amphiphilic calix[6]arene, alone or complexed with an axle to form a pseudo-rotaxane, has been embedded into liposomes prepared from 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and the permeability of the membrane-doped liposomes towards Cl - ions has been evaluated by using lucigenin as the fluorescent probe. The pseudo-rotaxane promotes transmembrane transport of Cl - ions more than calix[6]arene does. Surprisingly, the quenching of lucigenin was very fast for liposomes doped with the positively charged axle alone. Molecular dynamics (MD) simulations and quantum-chemical calculations were also carried out for providing a semi-quantitative support to the experimental results., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Tris(phenylureido)calix[6]arene is endowed with unique properties that make it a valuable macrocyclic component for the synthesis of mechanically interlocked molecules. Its three-dimensional and intrinsically nonsymmetric structure is kinetically selective toward two processes: (i) in apolar media, the threading of bipyridinium based axle-like components takes place exclusively from the upper rim; (ii) S N 2 alkylation reactions of a pyridylpyridinium precursor engulfed in the cavity occur selectively at pyridylpyridinium nitrogen atom located at the macrocycle upper rim (active template synthesis). Here we exploit such properties to prepare two series of [3]rotaxanes, each consisting of three sequence isomers that arise from the threading of two identical but nonsymmetric wheels on a symmetric thread differing only for the reciprocal orientation of the macrocycles. The features of the calix[6]arene and the active template synthetic approach, together with a careful selection of the precursors, enabled us to selectively synthesise the [3]rotaxane sequence isomers of each series with fast kinetics and high yields., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We report the synthesis of a versatile trifluoromethylsulfonamide calix[6]arene derivative with Brønsted acid features which can influence both molecular recognition and catalytic application. Indeed, in low polarity media, the trifluoromethyl-containing supramolecular wheel is able to respond to the complexation with charged species as a function of its selective ion-pair recognition. In parallel, the enhanced acidity is the key to promote Michael additions of indoles to nitroalkenes under pseudo-physiological reaction conditions (H2O, 37 °C).

We describe the application of a novel family of trisulfonamide (TSA) calix[6]arenes in general acid catalysis. Hydrogen-bonding interactions between acidic TSA and methanol boosted the reactivity of the Michael addition of indoles to nitroalkene derivatives. The transformation occurs at a low catalyst loading of 5 mol%, allowing for the synthesis of nitroalkanes with good yields and functional group tolerance.

We describe the synthesis of a new class of trisulfonamide calix[6]arene-based wheels that can bind dialkylviologen salts, in apolar media. The threading process occurs through a selective ion-pair recognition, established by the sulfonamide groups with the counterions of the bipyridinium salts, that dictates a conformational rearrangement of the corresponding pseudorotaxanes.

This work describes a calix[6]arene-based wheel that binds, in non-polar media, a stilbazolium salt to yield a mixture of pseudorotaxane orientational isomers. The isomer's abundance ratio evolves with time and can be reversibly tuned by adjusting the temperature. The spectroscopic properties, and notably the emission spectrum, of the bound guest depend on its orientation inside the non-palindromic wheel, suggesting such a system as a switch with spectroscopic readout., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Operating molecular machines are based on switchable systems whose components can be set in motion in a controllable fashion. The presence of nonsymmetrical elements is a mandatory requirement to obtain and demonstrate the unidirectionality of motion. Calixarene-based macrocycles have proved to be very efficient hosts in the design of oriented rotaxanes and of pseudorotaxanes with strict control over the direction of complexation. A series of two-station rotaxanes based on bipyridinium-ammonium axles was synthesized and characterized. A recently reported supramolecularly assisted strategy for the synthesis of different orientational isomers was exploited, and the ammonium unit was identified as a proper secondary station for the calixarene. Displacement of the macrocycle was triggered by electrochemical reduction of the bipyridinium primary station, and it was shown that the shuttling is influenced both by the length of the chain of the axle component and by the position of the secondary station with respect to the calixarene rims., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)