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Time-resolved and steady-state photoluminescence, reflectivity, and absorption experiments were performed on CdSe quantum dots in ZnxCdyMg1-x-ySe barriers. Studies of the capture times of the photoexcited carriers into the quantum dots and of electron-hole recombination times inside the dots were performed. Photoluminescence rise time yielded capture times from 20 ps to 30 ps. All samples exhibit fast and slow photoluminescence decays, consistent with observing two independent but energetically overlapping decays. The faster relaxation times for the sample emitting in the blue range is 90 ps, whereas for the two samples emitting in the green it is 345 ps and 480 ps. The slower relaxation times for the sample emitting in blue is 310 ps, whereas for the samples emitting in green is 7.5 ns. These results are explained on the basis of the structural differences among the quantum-dot samples. [ABSTRACT FROM AUTHOR]

Time-resolved luminescence spectroscopy is described for high Tc YBa2Cu3O7-x under 8 ps/530 nm laser ablation. The emission spectrum covered most of the visible spectrum and showed emission lines from ions. The emission profiles in time consist of fast (≊25 ps) and slow (≊1 ns) decay components. [ABSTRACT FROM AUTHOR]

Competing Interests: Conflicts of Interest, Funding: Please see DISCLOSURES at the end of this article.

We report the synthesis and characterization of sulfated pillar[5]arene hosts (P5S 2 -P5S 10 ) that differ in the number of sulfate substituents. All five P5S n hosts display high solubility in water (73-131 mM) and do not undergo significant self-association according to 1 H NMR dilution experiments. The x-ray crystal structures of P5S 6 , P5S 6  ⋅ Me 6 HDA, P5S 8  ⋅ Me 6 HDA, and P5S 10  ⋅ Me 6 HDA reveal one intracavity molecule of Me 6 HDA and several external molecules of Me 6 HDA which form a network of close methonium ⋅ ⋅ ⋅ sulfate interactions. The thermodynamic parameters of complexation between P5S n and the panel of guests was measured by direct or competitive isothermal titration calorimetry. We find that the binding free energy toward a guest becomes more negative as the number of sulfate substituents increase. Conversely, the binding free energy of a specific sulfated pillar[5]arene toward a homologous series of guests becomes more negative as the number of NMe groups increases. The ability to tune the host ⋅ guest affinity by changing the number of sulfate substituents will be valuable in supramolecular polymers, separation materials, and latching applications., (© 2024 The Author(s). Chemistry - A European Journal published by Wiley-VCH GmbH.)

Nuclear energy makes large contributions toward meeting global energy needs, but societal concerns remain high given the impacts of the intended release of radioactive materials including 129 I and 131 I. In this paper we explore the use of a homologous series of acyclic CB[n] type hosts (H1-H4) as adsorbents of iodine from the vapor phase. We find that H2-H4, but not H1 - perform well in this application with uptake capacities of 2.2 g g -1 , 1.5 g g -1 , and 1.9 g g -1 , respectively. The chemisorptive uptake process involves partial oxidation of catechol walled H2 to quinone walled host and capture of I 3 - and I 5 - . Solid H2 can be regenerated by treatment with Na 2 S 2 O 4 and reused at least five times. The x-ray crystal structure of H2 is also reported., (© 2024 Wiley-VCH GmbH.)

Introduction: Preventive care practices are a challenge in community care. This study examined hantavirus preventive practices and their relationship with personal and social factors, lifestyle, and cultural beliefs., Method: An explanatory sequential mixed methods design, guided by Leininger's Theory of Culture Care Diversity and Universality, was used in two phases: (a) a cross-sectional relational design ( n = 109) and (b) ethnonursing research ( n = 30), in an endemic community in Panama. Univariate and bivariate analyses were used to analyze the quantitative data, whereas the Leininger's analysis model was used to analyze the qualitative data., Results: In the quantitative phase, the most frequent preventive practice was household hygiene, and the least frequent was vector control. Two of the eight preventive practices were associated with personal factors and two were associated with social factors. In the qualitative phase, lifestyle, beliefs, and context were found to influence the adoption of hantavirus preventive practices and help explain the quantitative findings., Discussion: Knowledge and understanding of the social and cultural contexts are essential for hantavirus prevention., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The accumulation of organic micropollutants (OMP) in aquatic systems is a major societal problem that can be addressed by approaches including nanofiltration, flocculation, reverse osmosis and adsorptive methods using insoluble materials (e.g. activated carbon, MOFs, nanocomposites). More recently, polymeric versions of supramolecular hosts (e.g. cyclodextrins, calixarenes, pillararenes) have been investigated as OMP sequestrants. Herein, we report our study of the use of water insoluble dimethylcatechol walled acyclic cucurbit[n]uril (CB[n]) hosts as solid state sequestrants for a panel of five OMPs. A series of hosts (H1-H4) were synthesized by reaction of glycoluril oligomer (monomer-tetramer) with 3,6-dimethylcatechol and fully characterized by spectroscopic means and x-ray crystallography. The solid hosts sequester OMPs from water with removal efficiencies exceeding 90 % in some cases. The removal efficiencies of the new hosts parallel the known molecular recognition properties of analogous water soluble acyclic CB[n]. OMP uptake by solid host occurs rapidly (≈120 seconds). Head-to-head comparison with CB[6] in batch-mode separation and DARCO activated carbon in flow-through separation mode show that tetramer derived host (H4) performs very well under identical conditions. The work establishes insoluble acyclic CB[n]-type receptors as a promising new platform for OMP sequestration., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The binding affinity of pillar[6]MaxQ toward a panel of neuromuscular blockers and neurotransmitters was measured in phosphate buffered saline by isothermal titration calorimetry and 1 H NMR spectroscopy. In vivo efficacy studies showed that P6MQ sequesters rocuronium and vecuronium and reverses their influence on the recovery of the train-of-four (TOF) ratio.

Diversity in supramolecular chemistry can showcase itself in many ways. This includes the diversity of thought and topics covered in research (from fundamental science to applications in biology and materials), as well as the diversity of people (e.g., diversity in race, gender, sexual orientation, country of origin, type of higher education institute, career stage,…). At the North American Supramolecular Chemistry (NASC) meetings, we aim to bring together the best that supramolecular chemistry has to offer in North America, create a sense of community and provide a platform for researchers at any stage of their career to present their work. NASC 2023 was the successful second edition of the NASC meeting series, and this proceedings article highlights the research and impressions of some of the speakers at NASC 2023.

Objective: The coronavirus disease 2019 (COVID-19) public health emergency has disproportionately affected older adults and their caregivers, requiring evidence-based and coordinated efforts to meet their health and social needs. This paper describes the role of the CDC Foundation as a knowledge broker working with public health partners to rapidly meet the unmet health, social, and other needs of older adults and caregivers during the COVID-19 pandemic. Type of program or service: Qualitative case study using the Role Model for Knowledge Brokering framework to describe a project that translated public health research into practice during the COVID-19 pandemic response., Methods: This case study documents the experiences of a US-based foundation serving as a knowledge broker, carrying out three roles: establishing research partnerships to study unmet health, social, and other needs of older adults and caregivers during COVID-19; coordinating with partners to identify evidence-based strategies; and rapidly implementing four emergency response pilot projects., Results: The emergency response pilot projects created included: an online resource library - -SearchFindHelp.org - of public health programs and resources for organisations serving older adults and caregivers; digital literacy training for older adults and caregivers; multicultural caregiver tools to serve rural and Asian American and Pacific Islander older adults; and a grant program to expand local, direct services for older adults. SearchFindHelp.org had 46 781 new users and 101 908 total views from June 2021-March 2023. Older adults and caregivers who participated in digital literacy training from May-September 2021 were more likely to find health resources online and schedule and attend an online doctor's visit. A paid media campaign in December 2021 was launched to raise awareness of multicultural caregiver tools. Ten community organisations expanded direct, local services for older adults., Lessons Learnt: This project highlights the valuable role a foundation can play as a knowledge broker in rapidly translating research into practice during a public health emergency response, to address emerging community needs., Competing Interests: None declared.

Pillar[6]MaxQ (P6AS) functions as an in vivo sequestration agent for methamphetamine and fentanyl. We use 1 H NMR, isothermal titration calorimetry, and molecular modelling to deduce the geometry and strength of the P6AS•drug complexes. P6AS forms tight complexes with fentanyl (K d =9.8 nM), PCP (17.1 nM), MDMA (25.5 nM), mephedrone (52.4 nM), and methamphetamine (101 nM). P6AS has good in vitro biocompatibility according to MTS metabolic, Adenylate Kinase cell death, and hERG ion channel inhibition assays, and the Ames fluctuation test. The no observed adverse effect level for P6AS is 45 mg/kg. The hyperlocomotion of mice treated with methamphetamine (0.5 mg/kg) can be ameliorated by treatment with P6AS (35.7 mg/kg) 5-minutes later, whereas the hyperlocomotion of mice treated with fentanyl (0.1 mg/kg) can be controlled by treatment with P6AS (5 mg/kg) up to 15-minutes later. P6AS has significant potential for development as a broad spectrum in vivo sequestration agent., Competing Interests: Declaration of Interests. The University of Maryland has filed a patent application covering the material in this publication with Weijian Xue and Lyle Isaacs named as inventors. Lyle Isaacs is a consultant, scientific advisor, and holds stock options in Clear Scientific (Cambridge, Massachusetts, USA).

We report that the direct macrocyclization of naphthalene monomers bearing ethyl ester functional groups delivers prism[5]arene derivatives, which can be deprotected to yield water-soluble prism[5]arenes (H1 and H3). 1 H NMR spectroscopy showed that dicationic guests bind with the hydrophobic cores buried inside the anisotropic magnetically shielding cavity. Isothermal titration calorimetry measurements showed that H1 and H3 are high-affinity hosts in PBS-buffered water with K a values exceeding 10 9  M -1 for a select guest. The complexation events are driven by the non-classical hydrophobic effect, CH⋅⋅⋅π interactions, and electrostatic interactions. Host H1 displays somewhat higher affinity toward a common guest than pillar[6]arene bearing carboxylic acid functional groups but is significantly less potent than pillar[6]arene bearing sulfate groups. H1 and H3 should be considered alongside other high affinity hosts for a variety of chemical and biological applications., (© 2022 Wiley-VCH GmbH.)

We report the molecular recognition properties of Pillar[ n ]MaxQ (P[ n ]MQ) toward a series of (methylated) amino acids, amino acid amides, and post-translationally modified peptides by a combination of 1 H NMR, isothermal titration calorimetry, indicator displacement assays, and molecular dynamics simulations. We find that P6MQ is a potent receptor for N -methylated amino acid side chains. P6MQ recognized the H3K4Me 3 peptide with K d = 16 nM in phosphate buffered saline.

Base-pair-driven toehold-mediated strand displacement (BP-TMSD) is a fundamental concept employed for constructing DNA machines and networks with a gamut of applications─from theranostics to computational devices. To broaden the toolbox of dynamic DNA chemistry, herein, we introduce a synthetic surrogate termed host-guest-driven toehold-mediated strand displacement (HG-TMSD) that utilizes bioorthogonal, cucurbit[7]uril (CB[7]) interactions with guest-linked input sequences. Since control of the strand-displacement process is salient, we demonstrate how HG-TMSD can be finely modulated via changes to the structure of the input sequence (including synthetic guest head-group and/or linker length). Further, for a given input sequence, competing small-molecule guests can serve as effective regulators (with fine and coarse control) of HG-TMSD. To show integration into functional devices, we have incorporated HG-TMSD into machines that control enzyme activity and layered reactions that detect specific microRNA.

Benzene, toluene and pyridine are widely used as essential raw materials in industry and laboratory research, with stringent purity requirements. Herein, we show that solid double-cavity host nor-seco-cucurbit[10]uril (ns-Q[10]) functions as an efficient adsorption separator for pyridine; benzene and toluene can be obtained in >99.9 % purity by this method. Thermal removal of pyridine from ns-Q[10]⋅Py 2 allows 10 separation cycles without erosion of performance. The geometry of the ns-Q[10]⋅Py 2 ternary complex was established by single-crystal X-ray diffraction methods. The ns-Q[10] cage facilitates the removal of pyridine from toluene and benzene, with >99.9 % purity for the separated compounds., (© 2022 Wiley-VCH GmbH.)

We report studies of the interaction of six acyclic CB[n]-type receptors toward a panel of drugs of abuse by a combination of isothermal titration calorimetry and 1 H NMR spectroscopy. Anthracene walled acyclic CB[n] host (M3) displays highest binding affinity toward methamphetamine (K d =15 nM) and fentanyl (K d =4 nM). Host M3 is well tolerated by Hep G2 and HEK 293 cells up to 100 μM according to MTS metabolic and adenylate kinase release assays. An in vivo maximum tolerated dose study with Swiss Webster mice showed no adverse effects at the highest dose studied (44.7 mg kg -1 ). Host M3 is not mutagenic based on the Ames fluctuation test and does not inhibit the hERG ion channel. In vivo efficacy studies showed that pretreatment of mice with M3 significantly reduces the hyperlocomotion after treatment with methamphetamine, but M3 does not function similarly when administered 30 seconds after methamphetamine., (© 2022 The Authors. ChemMedChem published by Wiley-VCH GmbH.)

Smart voltage-gated nanofiltration membranes have enormous potential for on-demand and precise separation of similar molecules, which is an essential element of sustainable water purification and resource recovery. However, the existing voltage-gated membranes are hampered by limited selectivity, stability, and scalability due to electroactive monomer dimerization. Here, for the first time, the host-guest recognition properties of cucurbit[7]uril (CB[7]) are used to protect the viologen derivatives and promote their assembly into the membrane by interfacial polymerization. Viologen functions as a voltage switch, whereas CB[7] complexation prevents its dimerization and improves its redox stability. The inhibited diffusion of the CB[7]-viologen complex enables the precise patterning of the surface structure. The resultant voltage-gated membrane displays 80% improved rejection performance, excellent recovery accuracy for similar molecules, and anti-fouling properties. This work not only provides an innovative strategy for the preparation of voltage-gated smart nanofiltration membranes but also opens up new avenues for ion-selective transmission in water treatment, bionic ion channels, and energy conversion.

We report an investigation of the complexation between a water soluble pillararene host (WP6) and a panel of hydrophobic cationic guests (G1 - G20) by a combination of 1 H NMR spectroscopy and isothermal titration calorimetry in phosphate buffered saline. We find that WP6 forms 1:1 complexes with K a values in the 10 4 - 10 9 M -1 range driven by favorable enthalpic contributions. This thermodynamic dataset serves as blinded data for the SAMPL9 challenge., Competing Interests: Conflicts of Interest. The authors have no conflicts of interest in relation to the work contained in the paper.

Methylated free amino acids are an important class of targets for host-guest chemistry that have recognition properties distinct from those of methylated peptides and proteins. We present comparative binding studies for three different host classes that are each studied with multiple methylated arginines and lysines to determine fundamental structure-function relationships. The hosts studied are all anionic and include three calixarenes, two acyclic cucurbiturils, and two other cleft-like hosts, a clip and a tweezer. We determined the binding association constants for a panel of methylated amino acids using indicator displacement assays. The acyclic cucurbiturils display stronger binding to the methylated amino acids, and some unique patterns of selectivity. The two other cleft-like hosts follow two different trends, shallow host (clip) following similar trends to the calixarenes, and the other more closed host (tweezer) binding certain less-methylated amino acids stronger than their methylated counterparts. Molecular modelling sheds some light on the different preferences of the various hosts. The results identify hosts with new selectivities and with affinities in a range that could be useful for biomedical applications. The overall selectivity patterns are explained by a common framework that considers the geometry, depth of binding pockets, and functional group participation across all host classes., (© 2021 The Authors. ChemBioChem published by Wiley-VCH GmbH.)

With the advent of novel advanced therapy medicinal products (ATMPs) for neurodegenerative diseases, their pathway to clinical trials and the therapeutic landscape has highlighted some new challenges, many of which are outlined in other chapters of this volume. The practical considerations of all these aspects from basic research and animal models through to clinical trials and eventual clinical implementation are significant. By and large, the major voices surrounding these challenges are the scientists and clinical teams who both develop the interventions and design and deliver the clinical trials to test these novel ATMPs. Their expertise is of course essential, but there is a key voice that can add considerable benefit to the pipeline, that of the lived experience of the disease being treated and the new intervention being considered. While still in their relative infancy in neurodegenerative disease, some ATMPs are already in clinical application in other disease areas, mainly cancer and inherited disorders. This more advanced status has raised some interesting questions about the role of the patient voice across all aspects of the therapeutic research and clinical delivery pipeline. This chapter highlights what has been learnt from the patient voice in their understanding and perspectives of ATMPs and in their experiences of clinical trials in neurodegenerative diseases to date. We discuss when, and how, including people living with neurodegenerative disease is of value in the development and implementation of ATMPs and the questions this collaborative effort can allow us to answer., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective.: To design and analyze the evidence of content validity, internal structure, and reliability of a questionnaire of preventive practices for hantavirus in an endemic community in the Panamanian context., Material and Methods.: Quantitative study of instrumental design. This research was conducted in four phases: Literature review, content validity through expert judgment with the individual aggregate method and the calculation of the V Aiken, pilot test and psychometric validation, through exploratory factor analysis (EFA) and reliability analysis of instrument scores with ordinal alpha., Results.: Content validity was evidenced and V Aiken values higher than 0.70 were reported in the lower limit of 95% CI. In the internal structure we identified that the 8 items underlie a single factor that explains 60.70% of the total variance of the test and with factor loadings greater than 0.40; during the reliability analysis, we obtained an ordinal alpha value of 0.84, which is considered good., Conclusions.: The Hantavirus preventive practical questionnaire is a brief instrument that shows acceptable psychometric properties to measure the activities or behaviors that people carry out to prevent hantavirus.

Androgens are synthesized in the brain, gonads, and adrenal glands, in both sexes, exerting physiologically important effects on the structure and function of the central nervous system. These effects may contribute to the incidence and progression of neurological disorders such as autism spectrum disorder, schizophrenia, and Alzheimer's disease, which occur at different rates in males and females. This review briefly summarizes the current state of knowledge with respect to the neuroplastic effects of androgens, with particular emphasis on the hippocampus, which has been the focus of much of the research in this field., Competing Interests: No competing financial interests exist., (© Nariko Kuwahara et al., 2021; Published by Mary Ann Liebert, Inc.)

We report the synthesis of two new acyclic sulfated acyclic CB[n]-type receptors (TriM0 and Me 4 TetM0) and investigations of their binding properties toward a panel of drugs of abuse (1-13) by a combination of 1 H NMR spectroscopy and isothermal titration calorimetry. TetM0 is the most potent receptor with K a ≥10 6  M -1 toward methamphetamine, fentanyl, MDMA and mephedrone. TetM0 is not cytotoxic toward HepG2 and HEK 293 cells below 100 μM according to MTS metabolic and adenylate kinase release assays and is well tolerated in vivo when dosed at 46 mg kg -1 . TetM0 does not inhibit the hERG ion channel and is not mutagenic based on the Ames fluctuation test. Finally, in vivo efficacy studies show that the hyperlocomotion of mice treated with methamphetamine can be greatly reduced by treatment with TetM0 up to 5 minutes later. TetM0 has potential as a broad spectrum in vivo sequestrant for drugs of abuse., (© 2021 Wiley-VCH GmbH.)

Naphthalene diimides (NDIs) are shown to arrange spontaneously co-facially with cucurbit[8]uril (CB[8]) in an aqueous environment through purely non-covalent interactions. The resultant 2 : 2 supramolecular complex of NDI and CB[8] is highly fluorescent (>30 times more than the constituent NDIs) due to the formation of NDI-NDI excimers within the supramolecular complex.

The efficiency and scope of two acyclic π-wall extended cucurbiturils, M2 and M3, exhibiting rapidly interconverting helical conformers for chiroptical sensing of amines, amino acids, alcohols, and terpenes at micromolar concentrations in water is evaluated. The formation of 1 : 1 host-guest complexes results in spontaneous induction of circular dichroism signals that can be used for accurate determination of the absolute configuration and enantiomeric composition of the analyte based on a simple mix-and-measure protocol.