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The photocatalytic degradation of p-chlorophenoxyacetic acid is studied in oxygenated aqueous suspensions of lanthanide oxide-doped titanium dioxide photocatalysts.

Photoinduced electron transfer was observed on supramolecular assemblies composed of bipyridinium salts and dialkoxy benzene-tethered ruthenium (II) trisbipyridine. Intramolecular pathways facilitated the transfer of electrons to the electron acceptors that were found in the supramolecular assemblies. Electron transfer also proceeded through a diffusional route associated with a free-uncomplexed compound.

The study compares conductivities of different conjugated and nonconjugated organic linked on both sides to small gold clusters with electrochemical results. The computation of the current uses a scattering approach and is based on an ab initio determination of the geometry and molecular levels of the gold-spacer-gold system at the Density Functional Theory level.

Elucidating the role of quantum coherences in energy migration within biological and artificial multichromophoric antenna systems is the subject of an intense debate. It is also a practical matter because of the decisive implications for understanding the biological processes and engineering artificial materials for solar energy harvesting. A supramolecular rhodamine heterodimer on a DNA scaffold was suitably engineered to mimic the basic donor–acceptor unit of light-harvesting antennas. Ultrafast 2D electronic spectroscopic measurements allowed identifying clear features attributable to a coherent superposition of dimer electronic and vibrational states contributing to the coherent electronic charge beating between the donor and the acceptor. The frequency of electronic charge beating is found to be 970 cm−1 (34 fs) and can be observed for 150 fs. Through the support of high level ab initio TD-DFT computations of the entire dimer, we established that the vibrational modes preferentially optically accessed do not drive subsequent coupling between the electronic states on the 600 fs of the experiment. It was thereby possible to characterize the time scales of the early time femtosecond dynamics of the electronic coherence built by the optical excitation in a large rigid supramolecular system at a room temperature in solution. [ABSTRACT FROM AUTHOR]

Binary hybrids have been investigated for the past few decades due to the emerging properties of nanoparticle composites. Electrostatically stabilized core–shell nanostructures composed of surface active magnetic nanoparticles (SAMNs) and differently charged carbon nanomaterials display specific electrochemical properties. In this work, a set of binary hybrids that include a new class of magnetic nanoparticles is presented and the electrochemical features of the hybrids are reported. Gallic acid derived carbon dots (GA-CDs), PEG derived graphene dots (PEG-GDs), and quaternized carbon dots (Q-CDs) characterized by different charged groups were used for the preparation of different complexes with SAMNs. Thus, a set of six binary nanomaterials was obtained, and characterized by electrochemical impedance spectroscopy, cyclic voltammetry and chronoamperometry, demonstrating significant differences in the charge transfer resistance, capacitive current, electrochemical performance, and reversibility with respect to the isolated subunits. Among them, the combination of Q-CDs with an excess of SAMNs led to a Q-CD@SAMN hybrid, which displayed peculiar electrocatalytic properties attributable to the influence of the strong electrostatic interactions exerted by Q-CDs on the SAMN surface. Notwithstanding their small fraction (around 1% w/w), Q-CDs oriented the electrocatalysis of SAMNs toward the selective electro-oxidation of polyphenols at low applied potentials (+0.1 V vs. SCE). Finally, the Q-CD@SAMN hybrid was used for the development of a coulometric sensor for polyphenols, composed of a simple carbon paste electrode in a small volume electrochemical flow cell (1 μL), and used for the complete direct electro-oxidation of polyphenols from plant extracts. [ABSTRACT FROM AUTHOR]

Objective Judicious selection of potential liver transplant candidates and close monitoring of progress are essential to successful outcomes. Pretransplant psychosocial evaluations are the norm, but the relationship between psychosocial (and neurocognitive status) and longer term medical outcomes is understudied. This exploratory study sought to examine the relationship between objective measures of pretransplant psychosocial and neurocognitive status and service utilization, transplant status, and all-cause mortality. Methods This retrospective chart review examined outcomes among 108 psychiatric, high-risk liver transplant candidates up to four years following initial evaluation. Predictor variables of outcomes included demographic, medical, neurocognitive, psychological, and mental health treatment variables. Results Transplant status and neurocognitive functioning were independently associated with all-cause mortality. None of the other variables were associated with outcomes. Conclusions Better neurocognitive functioning in high-risk liver transplant candidates may allow for greater involvement in medical care and/or compliance with treatment recommendations. More aggressive assessment and management of neurocognitive dysfunction may improve outcomes. Objective measures identified significant psychopathology typical of liver transplant candidates but were not associated with outcomes; engagement in specialized mental health care may have attenuated this relationship. Further study is needed to better understand the relationship between psychosocial functioning and outcomes. [ABSTRACT FROM AUTHOR]

The article offers information on the MULTI project which is a Multi-Valued and Parallel Molecular Logic project. It informs that the aim of the project is to physically realize massively parallel computations, multivalues computations and inbuilt memory. It further informs that the project tries to utilize the large set of degrees of freedom to implement the functionality of molecular computation in a solid state environment.

Background: Memphis and Shelby County, Tennessee, experienced an epidemic of hepatitis A in 1994 and 1995. More than 1700 cases were reported.Objective: To characterize the clinical features of patients hospitalized during a large urban epidemic of hepatitis A.Design: Retrospective chart review.Setting: 15 acute care hospitals in Shelby County, Tennessee.Patients: 256 patients hospitalized with acute hepatitis A.Measurements: Laboratory findings (such as prothrombin time and bilirubin level), complications, and mortality.Results: The median patient age was 26 years. Thirty-nine complications occurred in 35 patients. Twenty patients (8%) had extrahepatic complications, and 5 (2%) died. Patients 40 years of age and older were more likely to have serious complications, including death (P = 0.014). Sixty-seven patients (26%) presented with coagulopathy (prothrombin time > or = 3 seconds prolonged). Fifty-four patients (21%) had a bilirubin level greater than 170 micromol/L (10 mg/dL).Conclusions: During this epidemic, hepatitis A caused serious illness and death. Complications were more frequent in patients 40 years of age and older, but young, healthy persons were also at risk for severe complications. [ABSTRACT FROM AUTHOR]

Oligo-adenine (polyA) is primarily known for its critical role in mRNA stability, translational status, and gene regulation. Beyond its biological functions, extensive research has unveiled the diverse applications of polyA. In response to environmental stimuli, single polyA strands undergo distinctive structural transitions into diverse secondary configurations, which are reversible upon the introduction of appropriate counter-triggers. In this review, we systematically summarize recent advances of noncanonical structures derived from polyA, including A-motif duplex, A-cyanuric acid triplex, A-coralyne-A duplex, and T ⋅ A-T triplex. The structural characteristics and mechanisms underlying these conformations under specific external stimuli are addressed, followed by examples of their applications in stimuli-responsive DNA hydrogels, supramolecular fibre assembly, molecular electronics and switches, biosensing and bioengineering, payloads encapsulation and release, and others. A detailed comparison of these polyA-derived noncanonical structures is provided, highlighting their distinctive features. Furthermore, by integrating their stimuli-responsiveness and conformational characteristics, advanced material development, such as pH-cascaded DNA hydrogels and supramolecular fibres exhibiting dynamic structural transitions adapting environmental cues, are introduced. An outlook for future developments is also discussed. These polyA derived, stimuli-responsive, noncanonical structures enrich the arsenal of DNA "toolbox", offering dynamic DNA frameworks for diverse future applications., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)