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Conical Intersection-Mediated Nonradiative Decay in an ESIPT-Active Imidazole Derivative.

Excited-state intramolecular proton transfer (ESIPT) is a photoinduced process that involves proton migration within an intramolecular hydrogen-bonded framework following electronic excitation and is often associated with large Stokes-shifted emission. However, the excited-state fate after proton transfer is not exclusively governed by radiative decay from a stabilized keto tautomer, and nonradiative relaxation may also play a decisive role. In this work, the excited-state relaxation mechanism of 2-(4,5-diphenyl-1H-imidazol-2-yl)phenol (DIP) was investigated using multireference electronic str

Reparameterization of Polarizable Force Fields for Studying Ion Transfer across Liquid-Liquid Interfaces.

We have developed a general scheme for refining classical polarizable molecular dynamics (MD) force fields that can accurately describe the molecular interactions in systems with liquid-liquid interfaces. While ab initio MD (AIMD) simulations can naturally describe molecular interactions, they are often so computationally expensive that simulating large system sizes and/or long time scales is usually infeasible. To resolve this, we parameterized efficient and accurate classical polarizable force fields that use AIMD reference data by minimizing both the relative entropy and the root mean squar

Absorption of methochlorpromazine in rat small intestinal everted sac.

The absorption of methochlorpromazine in rat small intestinal everted sac was investigated. 0.22% of the drug added in mucosal fluid was transferred to serosal fluid for 30 min at 37 degrees C. The absorption of the drug was slightly inhibited by choline, and more markedly inhibited by more hydrophobic quaternary ammonium cations such as tetraethylammonium and cetyltrimethylammonium. Moderate inhibition was observed by a polyamine, spermine. The absorption rate of methochlorpromazine markedly depended on temperature. The Arrhenius plot of the apparent transfer rate constant revealed high activ

Hyperbranched dielectric polymer networks exhibiting giant energy storage density at 250 °C.

Harsh-environment requirements of electrical and electronic systems demand advanced dielectrics with high energy storage density at elevated temperatures. Heat-resistant polymers are usually designed with densely packed molecular chains to maintain structural integrity. Unfortunately, the narrowed inter-chain spacing causes severe charge transfer under high electro-thermal fields, prohibiting capacitive energy storage beyond 200 °C. Here we report hyperbranched dielectric polymer networks as a solution to the persistent challenge. The hyperbranched topological junctions not only transform the

Momentum-resolved non-resonant inelastic x-ray scattering study of C60.

For large molecular systems such as C60, accurate ab initio calculations remain challenging, making experimental methods a more reliable alternative. In this work, we employed the non-resonant inelastic x-ray scattering technique to study the electronic excitation dynamics of C60. The measurements spanned a momentum transfer range of 0.63-5.10 a.u. at a photon energy of ∼10 keV with an energy resolution around 1.0 eV. The dynamic structure factors in the excitation energy range of 5-500 eV and the generalized oscillator strengths for the core excitations of π*←1s were determined on absolute sc

Toward developing a compact total artificial heart using a soft robotic fluidic transmission system.

Cardiovascular diseases are a leading cause of mortality, with limited possibilities for transplantation due to a critical shortage of donor hearts. Replacing the heart with total artificial hearts (TAHs) remains challenging, due to size constraints and energy requirements, among others. To address this, we introduce the LIMO heart, a compact TAH concept based on an efficient soft fluidic transmission system. By reducing actuator volume and enhancing energy transfer, LIMO enables a more compact and efficient design. We developed a soft ventricle prototype using thin-walled pouch actuators that…

Структурный анализ процесса сбора света с помощью антенн, содержащих родопсины в морской архееи Асгарда.

Акватические бактериальные редопсиновые протонные насосы собирают световую энергию для фотогетертрофного роста и, как известно, содержат гидроксилированные каротеи, расширяющие волны используемого света, но они не характеризуются морской археей. Здесь, комбинируя морскую хромофорную экстракт с очищенными архейскими родопсинами, выявленными в морских метагеномах, мы показываем передачу легкой энергии из различных гидроксилоидных каротеоидных в геймдаллархаэ (HeimdallRs) из некультурных морских планктонных членов «Candidatus Cariarachaeceae» (Candidatus Asgardarchaeota). Эти светообрабатывающие

Совпадение в аннотации оригинала
Aquatic bacterial rhodopsin proton pumps harvest light energy for photoheterotrophic growth and are known to contain hydroxylated carotenoid … romophore extract with purified archaeal rhodopsins identified in marine metagenomes, we show light energy transfer from diverse hydroxylated carotenoids to heimdallarchaeial rhodopsins (HeimdallRs) from uncultured marine planktonic members of 'Candidatus Kariarchaeaceae' ('Candidatus Asgardarchaeota'). These light-harvesting antennas absorb in the blue-light ran …

Extracellular electron transfer increases fermentation in lactic acid bacteria via a hybrid metabolism.

Energy conservation in microorganisms is classically categorized into respiration and fermentation; however, recent work shows some species can use mixed or alternative bioenergetic strategies. We explored the use of extracellular electron transfer for energy conservation in diverse lactic acid bacteria (LAB), microorganisms that mainly rely on fermentative metabolism and are important in food fermentations. The LAB Lactiplantibacillus plantarum uses extracellular electron transfer to increase its NAD+/NADH ratio, generate more ATP through substrate-level phosphorylation, and accumulate biomas

DNA-based programming of quantum dot valency, self-assembly and luminescence.

The electronic and optical properties of colloidal quantum dots, including the wavelengths of light that they can absorb and emit, depend on … is confirmed with transmission electron microscopy, and photophysical studies are used to quantify energy transfer among the constituent components. Through changes in pH, the conformation of the complexes can also be reversibly switched, turning on and off the transfer of energy between the constituent quantum dots.

Perturbative ensemble density functional theory applied to charge transfer excitations.

Charge transfer excitation energies are known to be challenging for standard time-dependent (TD) density functional theory (DFT) calculations. Perturbative ensemble DFT (pEDFT) was suggested as an easy-to-implelemt, low-cost alternative to TDDFT, because it is an in principle exact theory for calculating excitation energies that produces useful valence excitation energies. Here, we examine analytically and numerically (based on the benzene-tetracyanoethylene complex) how well pEDFT performs in the charge transfer limit. We find that pEDFT is qualitatively correct in that it follows the Mullike

A FRET probe based on flavonol-benzothiazole for the detection of viscosity and SO2 derivatives.

Sulfur dioxide (SO2) and viscosity play important roles in living organisms, and abnormal levels of them are associated with many diseases. Hence, a bifunctional fluorescence probe (E)-3-(2-(4-(4-(4-(6-fluoro-3-hydroxy-4-oxo-4H-chromen-2-yl)benzoyl)piperazin-1-yl)styryl)benzo-[d]thiazol-3-ium-3-yl)propane-1-sulfonate (HFBT) with fluorescence resonance energy transfer (FRET) properties was successfully constructed by using 3-hydroxyflavonol as the energy donor and benzothiazole sulphonate derivatives as the energy acceptor, and it can be used for the detection of SO2 derivatives (HSO3-/HSO32-) …

Mitochondrial transfer in the progression and treatment of cardiac disease.

Mitochondria are the primary site for energy production and play a crucial role in supporting normal physiological functions of the human body. In cardiomyocytes (CMs), mitochondria can occupy up to 30 % of the cell volume, providing sufficient energy for CMs contraction and relaxation. However, some pathological conditions such as ischemia, hypoxia, infection, and the side effect of drugs, can cause mitochondrial dysfunction in CMs, leading to various myocardial injury-related diseases including myocardial infarction (MI), myocardial hypertrophy, and heart failure. Self-control of mitochondri

Bio serves nano: biological light-harvesting complex as energy donor for semiconductor quantum dots.

Light-harvesting complex (LHCII) of the photosynthetic apparatus in plants is attached to type-II core-shell CdTe/CdSe/ZnS nanocrystals (quantum dots, QD) exhibiting an absorption band at 710 nm and carrying a dihydrolipoic acid coating for water solubility. LHCII stays functional upon binding to the QD surface and enhances the light utilization of the QDs significantly, similar to its light-harvesting function in photosynthesis. Electronic excitation energy transfer of about 50% efficiency is shown by donor (LHCII) fluorescence quenching as well as sensitized acceptor (QD) emission and corrob…

Ultrafast solvent-to-solute proton transfer mediated by intermolecular coherent vibrations.

Ultrafast photoinduced excited-state proton transfer (ESPT) plays a crucial role in protecting biomolecules and functional materials from photodamage. However, the influence of solute-solvent interactions on ESPT dynamics remains under active investigation. Here, we present an ultrafast spectroscopic study of ESPT in the photobase 2-(2´-pyridyl)benzimidazole (PBI) in methanol. Ultrafast absorption spectroscopy, supported by quantum chemical calculations, reveals three distinct kinetic steps: (1) a 2.2 ps solvent-to-solute proton transfer, (2) subsequent nonradiative relaxation to the ground st

Structural Insights and Challenges in the Supercomplexes Formed by Photosystem I in Phototrophs.

Photosystem I (PSI) is a central component of photosynthesis, driving essential processes such as light energy conversion and energy metabol … teins in land plants and Lhcr proteins in red algae, is crucial for optimizing light absorption and energy transfer under varying light conditions. Structural evidence also supports the existence of PSI-PSII supercomplexes, revealing direct interactions that facilitate energy transfer between photosystems and protect them from photodamage. These findings highligh …

Soft tissue can absorb surprising amounts of energy during knee exoskeleton use.

Soft tissue at the human-exoskeleton interface can deform under load to absorb, return and dissipate the mechanical energy generated by the exoskeleton. These soft tissue effects are often not accounted for and may mislead researchers on the actual joint assistance an exoskeleton provides. We assessed the effects of soft tissue by quantifying the performance and energy distribution of a knee exoskeleton under different assistance strategies using a synthetic lower limb phantom. The phantom emulated knee kinematics and soft tissue deformation at the exoskeleton interface. We loaded the exoskele

Synergistic mechanism of formaldehyde adsorption by intrinsic defects and carboxyl groups on the surface of carbon materials.

The adsorption of formaldehyde on the original carbon material is limited. Determining the synergistic adsorption of formaldehyde by different defects on the carbon material is necessary for comprehensively understanding the mechanism of formaldehyde adsorption on the surface of the carbon material. The synergistic effect of intrinsic defects and oxygen-containing functional groups on formaldehyde adsorption on the surface of carbon materials was simulated and verified by experiments. Based on the density functional theory, the adsorption of formaldehyde on different carbon materials was simul

Graphene as a Sensor for Lung Cancer: Insights into Adsorption of VOCs Using vdW DFT.

The adsorption mechanism of individual volatile organic compounds (VOCs) on the surface of graphene is investigated using nonempirical van der Waals (vdW) density functional theory. The VOCs chosen as adsorbates are ethanol, benzene, and toluene, which are found in the exhaled breath of lung cancer patients. The most energetically favorable configurations of the adsorbed systems, adsorption energy profiles, charge transfer, and work function are calculated. The fundamental insight into the interactions between the considered VOC molecules and graphene through molecular doping, i.e., charge tra

On the efficiency of FES cycling: a framework and systematic review.

Research and development in the art of cycling using functional electrical stimulation (FES) of the paralysed leg muscles has been going on for around thirty years. A range of physiological benefits has been observed in clinical studies but an outstanding problem with FES-cycling is that efficiency and power output are very low. The present work had the following aims: (i) to provide a tutorial introduction to a novel framework and methods of estimation of metabolic efficiency using example data sets, and to propose benchmark measures for evaluating FES-cycling performance; (ii) to systematica

Emission profile of rapeseed methyl ester and its blend in a diesel engine.

Fatty acid methyl esters, also known as biodiesel, have been shown to have a great deal of potential as petro-diesel substitutes. Biodiesel comprise a renewable alternative energy source, the development of which would clearly reduce global dependence on petroleum, and would also help to reduce air pollution. This paper analyzes the fuel properties of rapeseed biodiesel and its blend with petro-diesel, as well as the emission profiles of a diesel engine on these fuels. Fuels performance studies were conducted in order to acquire comparative data regarding specific fuel consumption and exhaust