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Atomistically detailed force field is employed to investigate the dynamics of a naturally abundant deep eutectic solvent at 328 K, composed of glucose, urea, and water in a 6:4:1 mass ratio. This study examines key dynamical processes, including translational motion, molecular reorientation, and hydrogen bond relaxation, with timescales ranging from a few picoseconds to a few nanoseconds. Characteristic times associated with the translational and the rotational motion increase with molecular size, i.e., water being the fastest and glucose the slowest. Jump length analysis shows that urea and glucose traverse fractions of their molecular diameters during jumps, suggesting gliding motion. We find that water molecules exhibit strong anisotropic reorientation, which is moderate for urea and nearly absent in the case of glucose molecules. Correlation analysis of analogous transport quantities among the constituents reveals that reorientation of the dipole axis is less coupled to the translational diffusion compared to the reorientation around the dipolar axis. Finally, we observe that hydrogen bond relaxation times for water and urea are highly dependent on the number of hydrogen bonds formed, while for glucose, the slower molecular motion influences its hydrogen-bond relaxation. [ABSTRACT FROM AUTHOR]

We show that the exact universal density functional of integer electronic charge leads to an extension to fractional charge in an asymptotic sense when it is applied to a system made of asymptotically separated densities. The extended functional is asymptotically local and is said to be i-local. The concept of i-locality is also applicable to nuclear external potentials, and a natural association exists between the localities of a density and a set of nuclei. Applying the functional to a system with nuclei distributed in two asymptotically separated locales requires an explicit search of the electronic charge at each locale with the constraint of the global charge. The determined number of electrons at each locale can be fractional. The molecular size consistency principle is realized as the result of the search. It is physically sensible to extend the molecule concept to include a fractional number of electrons (called fractional molecule henceforth) as a localized observable. The physical validity of fractional molecules is equivalent to the asymptotic separability of molecules, a basic assumption in molecular research. A one-to-one mapping between a fractional molecule's density and external potential is shown to exist with a nondegenerate condition. The global one-to-one mapping required by the Hohenberg–Kohn first theorem is realized through the aforementioned global search for molecular charges. Furthermore, the well-known piecewise linearity of the universal functional with respect to the number of electrons is necessary for an approximate i-local universal functional to be broadly accurate for any integer number of electrons. The Kohn–Sham (KS) noninteracting kinetic energy functional for a fractional molecule is well-defined and has the same form as that for a system of an integer number of electrons. It is shown to be i-local. A nondegenerate, noninteracting ensemble v-representable fractional density is simultaneously noninteracting wavefunction representable. A constrained search over those representing wavefunctions yields the definition of an exchange–correlation functional pertaining to fractional occupancies of KS orbitals. The functional is shown to be an upper bound to the formal KS exchange–correlation energy of a fractional molecule and includes a strong correlation. It yields the correct result for a well-designed example of effective fractional occupancies in the literature. [ABSTRACT FROM AUTHOR]

We present molecular dynamics simulations to study the thermodynamics of nanobubbles trapped at the mouth of narrow slit pores. Except when the slit dimensions are comparable to typical molecular sizes, the predictions of macroscopic thermodynamic theory are recovered by our simulations. Our simulations confirm that in this case, the internal pressure of stable nanobubbles is independent of the bubble radius and the surface tension and only depends on the bulk properties of the solute-containing solution, i.e., the chemical potential balance. However, in the case of extreme confinement, the pressure is not a suitable quantity to describe the thermodynamics of the bubbles, while the balance of the chemical potentials is. [ABSTRACT FROM AUTHOR]

Depletion interactions are thought to significantly contribute to the organization of intracellular structures in the crowded cytosol. The strength of depletion interactions depends on physical parameters such as the depletant number density and the depletant size ratio. Cells are known to dynamically regulate these two parameters by varying the copy number of proteins of a wide distribution of sizes. However, mammalian cells are also known to keep the total protein mass density remarkably constant, to within 0.5% throughout the cell cycle. We thus ask how the strength of depletion interactions varies when the total depletant mass is held fixed, a.k.a. fixed-mass depletion. We answer this question via scaling arguments, as well as by studying depletion effects on networks of reconstituted semiflexible actin in silico and in vitro. We examine the maximum strength of the depletion interaction potential U∗ as a function of q, the size ratio between the depletant and the matter being depleted. We uncover a scaling relation U∗ ∼ qζ for two cases: fixed volume fraction φ and fixed mass density ρ. For fixed volume fraction, we report ζ < 0. For the fixed mass density case, we report ζ > 0, which suggests that the depletion interaction strength increases as the depletant size ratio is increased. To test this prediction, we prepared our filament networks at fixed mass concentrations with varying sizes of the depletant molecule poly(ethylene glycol) (PEG). We characterize the depletion interaction strength in our simulations via the mesh size. In experiments, we observe two distinct actin network morphologies, which we call weakly bundled and strongly bundled. We identify a mass concentration where different PEG depletant sizes lead to weakly bundled or strongly bundled morphologies. For these conditions, we find that the mesh size and intra-bundle spacing between filaments across the different morphologies do not show significant differences, while the dynamic light scattering relaxation time and storage modulus between the two states do show significant differences. Our results demonstrate the ability to tune actin network morphology and mechanics by controlling depletant size and give insights into depletion interaction mechanisms under the fixed-depletant-mass constraint relevant to living cells. [ABSTRACT FROM AUTHOR]

The titular domain-based local pair natural orbital (DLPNO) approximation is the most widely used method for extending correlated wave function models to large molecular systems, yet its fidelity for intermolecular interaction energies in large supramolecular complexes has not been thoroughly vetted. Non-covalent interactions are sensitive to tails of the electron density and involve nonlocal dispersion that is discarded or approximated if the screening of pair natural orbitals (PNOs) is too aggressive. Meanwhile, the accuracy of the DLPNO approximation is known to deteriorate as molecular size increases. Here, we test the DLPNO approximation at the level of second-order Møller–Plesset perturbation theory (MP2) and coupled-cluster theory with singles, doubles, and perturbative triples [CCSD(T)] for a variety of large supramolecular complexes. DLPNO-MP2 interaction energies are within 3% of canonical values for small dimers with ≲10 heavy atoms, but for larger systems, the DLPNO approximation is often quite poor unless the results are extrapolated to the canonical limit where the threshold for discarding PNOs is taken to zero. Counterpoise correction proves to be essential in reducing errors with respect to canonical results. For a sequence of nanoscale graphene dimers up to ( C 96 H 24 ) 2 , extrapolated DLPNO-MP2 interaction energies agree with canonical values to within 1%, independent of system size, provided that the basis set does not contain diffuse functions; these cause the DLPNO approximation to behave erratically, such that results cannot be extrapolated in a meaningful way. DLPNO-CCSD(T) calculations are typically performed using looser PNO thresholds as compared to DLPNO-MP2, but this significantly impacts accuracy for large supramolecular complexes. Standard DLPNO-CCSD(T) settings afford errors of 2–6 kcal/mol for dimers involving coronene (C24H12) and circumcoronene (C54H18), even at the DLPNO-CCSD(T1) level. [ABSTRACT FROM AUTHOR]

Inspired by biological channels, achieving precise separation of ion/water and ion/ion requires finely tuned pore sizes at molecular dimensions and deliberate exposure of charged groups. Covalent organic frameworks (COFs), a class of porous crystalline materials, offer well-defined nanoscale pores and diverse structures, making them excellent candidates for nanofluidic channels that facilitate ion and water transport. In this study, we perform molecular simulations to investigate the structure and kinetics of water and ions confined within the typical COFs with varied exposure of charged groups. The COFs exhibit vertically arrayed nanochannels, enabling diffusion coefficients of water molecules within COFs to remain within the same order of magnitude as in the bulk. The motion of water molecules manifests in two distinct modes, creating a mobile hydration layer around acid groups. The ion diffusion within COFs displays a notable disparity between monovalent (M+) and divalent (M2+) cations. As a result, the selectivity of M+/M2+ can exceed 100, while differentiation among M+ is less pronounced. In addition, our simulations indicate a high rejection (R > 98%) in COFs, indicating their potential as ideal materials for desalination. The chemical flexibility of COFs indicates that would hold significant promise as candidates for advanced artificial ion channels and separation membranes. [ABSTRACT FROM AUTHOR]

This article explores the shift in chemical physics research towards studying single molecules and nanoparticles instead of bulk samples. Advancements in experimental techniques, such as single-molecule absorption and fluorescence spectroscopy, have made this shift possible. The article discusses various observations made through single-molecule spectroscopy, as well as theoretical considerations and applications in biology, materials science, and nanophotonics. It provides a summary of studies conducted using single-molecule spectroscopy in different disciplinary categories, demonstrating its interdisciplinary nature. The article concludes by discussing the challenges and future directions in the field, including integrating particle tracking with time-dependent spectroscopy and actively manipulating nanoscale objects. [Extracted from the article]

Multicomponent macromolecular mixtures often form higher-order structures, which may display non-ideal mixing and aging behaviors. In this work, we first propose a minimal model of a quaternary system that takes into account the formation of a complex via a chemical reaction involving two macromolecular species; the complex may then phase separate from the buffer and undergo a further transition into a gel-like state. We subsequently investigate how physical parameters such as molecular size, stoichiometric coefficients, equilibrium constants, and interaction parameters affect the phase behavior of the mixture and its propensity to undergo aging via gelation. In addition, we analyze the thermodynamic stability of the system and identify the spinodal regions and their overlap with gelation boundaries. The approach developed in this work can be readily generalized to study systems with an arbitrary number of components. More broadly, it provides a physically based starting point for the investigation of the kinetics of the coupled complex formation, phase separation, and gelation processes in spatially extended systems. [ABSTRACT FROM AUTHOR]

We present a simple approximation to estimate the largest charge that a given molecule can hold until fragmentation into smaller charged species becomes more energetically favorable. This approximation solely relies on the ionization potentials, electron affinities of the parent and fragment species, and also on the neutral parent's dissociation energy. By parameterizing these quantities, it is possible to obtain analytical phase diagrams of polycationic stability. We demonstrate the applicability of this approach by discussing the maximal charge dependence on the size of the molecular system. A numerical demonstration for linear polyenes, monocyclic annulenes, and helium clusters is provided. [ABSTRACT FROM AUTHOR]

Static and time-dependent quantum-mechanical approaches have been employed in the literature to characterize the physics of light-emitting molecules and nanostructures. However, the electromagnetic emission induced by an input current has remained beyond the realm of molecular simulations. This is the challenge addressed here with the help of an equation of motion for the density matrix coupled to a photon bath based on a Redfield formulation. This equation is evolved within the framework of the driven-Liouville von Neumann approach, which incorporates open boundaries by introducing an applied bias and a circulating current. The dissipated electromagnetic power can be computed in this context from the time derivative of the energy. This scheme is applied in combination with a self-consistent tight-binding Hamiltonian to investigate the effects of bias and molecular size on the electroluminescence of metallic and semiconducting chains. For the latter, a complex interplay between bias and molecular length is observed: there is an optimal number of atoms that maximizes the emitted power at high voltages but not at low ones. This unanticipated behavior can be understood in terms of the band bending produced along the semiconducting chain, a phenomenon that is captured by the self-consistency of the method. A simple analytical model is proposed that explains the main features revealed by the simulations. The methodology, applied here at a self-consistent tight-binding level but extendable to more sophisticated Hamiltonians such as density functional tight binding and time dependent density functional theory, promises to be helpful for quantifying the power and quantum efficiency of nanoscale electroluminescent devices. [ABSTRACT FROM AUTHOR]

In this work, the effects of finite size on the determination of the three-phase coexistence temperature (T3) of the carbon dioxide (CO2) hydrate have been studied by molecular dynamic simulations and using the direct coexistence technique. According to this technique, the three phases involved (hydrate–aqueous solution–liquid CO2) are placed together in the same simulation box. By varying the number of molecules of each phase, it is possible to analyze the effect of simulation size and stoichiometry on the T3 determination. In this work, we have determined the T3 value at 8 different pressures (from 100 to 6000 bar) and using 6 different simulation boxes with different numbers of molecules and sizes. In two of these configurations, the ratio of the number of water and CO2 molecules in the aqueous solution and the liquid CO2 phase is the same as in the hydrate (stoichiometric configuration). In both stoichiometric configurations, the formation of a liquid drop of CO2 in the aqueous phase is observed. This drop, which has a cylindrical geometry, increases the amount of CO2 available in the aqueous solution and can in some cases lead to the crystallization of the hydrate at temperatures above T3, overestimating the T3 value obtained from direct coexistence simulations. The simulation results obtained for the CO2 hydrate confirm the sensitivity of T3 depending on the size and composition of the system, explaining the discrepancies observed in the original work by Míguez et al. [J. Chem Phys. 142, 124505 (2015)]. Non-stoichiometric configurations with larger unit cells show a convergence of T3 values, suggesting that finite-size effects for these system sizes, regardless of drop formation, can be safely neglected. The results obtained in this work highlight that the choice of a correct initial configuration is essential to accurately estimate the three-phase coexistence temperature of hydrates by direct coexistence simulations. [ABSTRACT FROM AUTHOR]

Polymers are known to wet nanopores with high surface energy through an atomically thin precursor film followed by slower capillary filling. We present here light interference spectroscopy using a mesoporous membrane-based chip that allows us to observe the dynamics of these phenomena in situ down to the sub-nanometer scale at milli- to microsecond temporal resolution. The device consists of a mesoporous silicon film (average pore size 6 nm) with an integrated photonic crystal, which permits to simultaneously measure the phase shift of thin film interference and the resonance of the photonic crystal upon imbibition. For a styrene dimer, we find a flat fluid front without a precursor film, while the pentamer forms an expanding molecular thin film moving in front of the menisci of the capillary filling. These different behaviors are attributed to a significantly faster pore-surface diffusion compared to the imbibition dynamics for the pentamer and vice versa for the dimer. In addition, both oligomers exhibit anomalously slow imbibition dynamics, which could be explained by apparent viscosities of six and eleven times the bulk value, respectively. However, a more consistent description of the dynamics is achieved by a constriction model that emphasizes the increasing importance of local undulations in the pore radius with the molecular size and includes a sub-nanometer hydrodynamic dead, immobile zone at the pore wall but otherwise uses bulk fluid parameters. Overall, our study illustrates that interferometric, opto-fluidic experiments with mesoporous media allow for a remarkably detailed exploration of the nano-rheology of polymeric liquids. [ABSTRACT FROM AUTHOR]

Beyond well-documented confinement and surface effects arising from the large internal surface and severely confining porosity of nanoporous hosts, the transport of nanoconfined fluids remains puzzling in many aspects. With striking examples such as memory, i.e., non-viscous effects, intermittent dynamics, and surface barriers, the dynamics of fluids in nanoconfinement challenge classical formalisms (e.g., random walk, viscous/advective transport)—especially for molecular pore sizes. In this context, while molecular frameworks such as intermittent Brownian motion, free volume theory, and surface diffusion are available to describe the self-diffusion of a molecularly confined fluid, a microscopic theory for collective diffusion (i.e., permeability), which characterizes the flow induced by a thermodynamic gradient, is lacking. Here, to fill this knowledge gap, we invoke the concept of "De Gennes narrowing," which relates the wavevector-dependent collective diffusivity D0(q) to the fluid structure factor S(q). First, using molecular simulation for a simple yet representative fluid confined in a prototypical solid (zeolite), we unravel an essential coupling between the wavevector-dependent collective diffusivity and the structural ordering imposed on the fluid by the crystalline nanoporous host. Second, despite this complex interplay with marked Bragg peaks in the fluid structure, the fluid collective dynamics is shown to be accurately described through De Gennes narrowing. Moreover, in contrast to the bulk fluid, the departure from De Gennes narrowing for the confined fluid in the macroscopic limit remains small as the fluid/solid interactions in severe confinement screen collective effects and, hence, weaken the wavevector dependence of collective transport. [ABSTRACT FROM AUTHOR]

The GW electron–hole interaction kernel, which includes two second-order exchange terms in addition to the first-order direct and exchange terms considered in the conventional GW + Bethe–Salpeter method, is applied to 10 two-molecular systems and six thermally activated delayed fluorescence (TADF) molecules in which inter- and intramolecular charge transfer excitations are expected to occur. The contributions of the two second-order exchange terms are almost zero for intermolecular charge transfer excitations and ∼0.75 eV for intramolecular charge transfer excitations according to our exciton analysis method with exciton wave functions. For TADF molecules, we found that the second-order exchange terms are more significant than the first-order exchange terms, and the contributions—even for local-type and delocalized-type excitations—are not negligibly small. We revealed that the two second-order exchange terms are proportional to the molecular size, the exciton binding energy, and the electron–hole overlap strength for intramolecular charge-transfer excitations. We believe that our findings are indispensable for further considerations of the GW method in the future. [ABSTRACT FROM AUTHOR]

The development of complex molecular scaffolds with defined folding properties represents a central challenge in chemical research. Proteins are natural scaffolds defined by a hierarchy of structural complexity and have evolved to manifest unique functional characteristics; for example, molecular recognition capabilities that facilitate the binding of target molecules with high affinity and selectivity. Utilizing these features, proteins have been used as a starting point for the design of synthetic foldamers and enhanced biocatalysts, as well as bioactive reagents in drug discovery. In this account, we describe the strategies used in our group to stabilize protein folds, ranging from the constraint of bioactive peptide conformations to chemical protein engineering. We discuss the evolution of peptides into peptidomimetics to inhibit protein–protein and protein–nucleic acid interactions, and the selective chemical modification of proteins to enhance their properties for biotechnological applications. The reported peptide- and proteomimetic structures cover a broad range of molecular sizes and they highlight the importance of structure stabilization for the design of functional biomimetics. 1 Introduction 2 Constraining the Conformation of Peptides 3 Peptide-Based Covalent Protein Modifiers 4 Chemical Protein Engineering 5 Conclusions [ABSTRACT FROM AUTHOR]

BACKGROUND: Natural emulsifiers are increasingly preferred by the food industry to meet consumers' demand for 'clean‐label' emulsion products. In the present study, 10 short‐term retrograded starches with unique molecular structures were explored to examine the relationships between starch structures and their ability to form stable oil‐in‐water emulsions. RESULTS: Waxy maize starch showed the largest value of contact angle and conductivity of emulsion, whereas potato and lentil starch showed the lowest value of contact angle and conductivity of emulsion, respectively. Emulsion prepared by rice starch showed the lowest, whereas that of sweet potato starch showed the highest value of viscosity. Consequentially, the emulsion stabilized with waxy maize and tapioca starch showed the smallest and less polydisperse droplets, resulting in a much higher emulsifying index. On the other hand, emulsion prepared with potato starch showed the highest stability compared to other starches. Correlation analysis suggested that starches with larger molecular size, a lower amylose content and shorter amylopectin short chains had a higher emulsification ability, whereas the amount of starch molecular interactions formed during short‐term retrogradation revealed no obvious linking to emulsion performances. CONCLUSION: These findings provided food industry with exciting opportunities to develop 'clean‐label' emulsions with desirable properties. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Due to their defined structure and large molecular size, giant molecular acceptors (GMAs) have achieved significant progress in device efficiency and stability for organic solar cells. Unlike the classical synthesis of GMAs by Stille coupling, which still suffers from high cost and lack of environmental sustainability, this work develops three GMAs via metal-free catalyzed reactions. By introducing varying quantities of malononitrile groups into the linker, the optoelectric properties of GMAs can be significantly regulated. A GMA containing only one malononitrile in the central linker unit exhibits a favorable absorption range, energy levels, and molecular packing, consequently achieving high efficiency and stability. Therefore this work provides a feasible approach to developing low-cost and scalable GMAs. [ABSTRACT FROM AUTHOR]

In this study, we apply QSPR analysis to some potent drugs used in blood cancer treatment using eccentricity‐based topological indices, which are structural descriptors capturing the shape and size of the molecules as well as their branching and symmetry. These index values are computed by partitioning the corresponding molecular graphs of the drugs for both vertex and edge sets based on their degrees and eccentricities. Then, cubic regression analysis is incorporated into the structural property relational models with these indices and their corresponding physical properties. This work also deals with the various statistical parameters that affect the goodness of the model, and their error analysis is discussed, thereby producing impactful regression models through the graphical depiction of their curve fits. [ABSTRACT FROM AUTHOR]

The safety engineering design of hydrogen systems and infrastructure, worker education and training, regulatory compliance, and engagement with other stakeholders are significant to the viability and public acceptance of hydrogen farms. The only way to ensure these are accomplished is for the field of hydrogen safety engineering (HSE) to grow and mature. HSE is described as the application of engineering and scientific principles to protect the environment, property, and human life from the harmful effects of hydrogen-related mishaps and accidents. This paper describes a whole hydrogen farm that produces hydrogen from seawater by alkaline and proton exchange membrane electrolysers, then details how the hydrogen gas will be used: some will be stored for use in a combined-cycle gas turbine, some will be transferred to a liquefaction plant, and the rest will be exported. Moreover, this paper describes the design framework and overview for ensuring hydrogen safety through these processes (production, transport, storage, and utilisation), which include legal requirements for hydrogen safety, safety management systems, and equipment for hydrogen safety. Hydrogen farms are large-scale facilities used to create, store, and distribute hydrogen, which is usually produced by electrolysis using renewable energy sources like wind or solar power. Since hydrogen is a vital energy carrier for industries, transportation, and power generation, these farms are crucial in assisting the global shift to clean energy. A versatile fuel with zero emissions at the point of use, hydrogen is essential for reaching climate objectives and decarbonising industries that are difficult to electrify. Safety is essential in hydrogen farms because hydrogen is extremely flammable, odourless, invisible, and also has a small molecular size, meaning it is prone to leaks, which, if not handled appropriately, might cause fires or explosions. To ensure the safe and dependable functioning of hydrogen production and storage systems, stringent safety procedures are required to safeguard employees, infrastructure, and the surrounding environment from any mishaps. [ABSTRACT FROM AUTHOR]

Discrete dimer or multimer acceptors have enhanced the stability of organic solar cells (OSCs) due to their slow diffusion kinetics resulting from their large molecular sizes. However, development of multimer acceptors with chain length longer than trimers has been challenging, which often require multistep reactions with low synthetic yield. In this study, a new discrete tetramer acceptor (TetA) using one‐pot reaction and subsequent purification processes is developed. During the purification, dimer (DA) and trimer acceptor (TA) are also obtained. The OSCs for TetA demonstrate a higher power conversion efficiency (PCE) of 16.14% than those for the discrete acceptors with shorter chain lengths, such as monomer acceptor (MA, 12.85%), DA (14.31%), and TA (15.10%). Additionally, despite having a similar number‐average molecular weight, TetA‐based OSCs exhibit a significantly higher PCE (16.14%) compared to OSCs based on a mixture of the acceptors (MixA) with dispersity (10.72%). Furthermore, the TetA‐based OSCs have the highest photostability and mechanical robustness among the series. For example, TetA‐based OSCs demonstrate superior photostability (t70% lifetime = 2180 h under 1‐sun illumination) and mechanical robustness (crack‐onset strain (COS) = 8%) compared to those based on MA (t70% = 220 h, and COS = 2%), or MixA (t70% = 745 h, and COS = 6%). [ABSTRACT FROM AUTHOR]

The heterogeneous selective hydrogenation of nitrile butadiene rubber (NBR) is an efficient method to generate high value‐added hydrogenated NBR. Nevertheless, the inherent large molecular size and high spatial hindrance of polymers lead to poor activity and metal loss. Herein, we report a simple support ammonia pretreatment strategy for the synthesis of efficient N‐doped Pd catalyst and applied for the NBR hydrogenation. The results reveal that N doping enhances electron transfer from the support to Pd more effectively than oxygen‐rich vacancy support, thereby substantially enhancing the electron cloud density and stability of the Pd sites. The formation of more electron‐rich Pd sites not only significantly enhances the adsorption‐activation ability of C=C and H2, but also lowers the apparent activation energy of the reaction. As a result, the Pd/N‐TiO2‐R demonstrates best activity with a hydrogenation degree (HD) of 98 % and a TOF value of 335 h−1, significantly higher than that of Pd/TiO2−R (HD=83 %, 282 h−1) and Pd/TiO2 (HD=74 %, 204 h−1). This strategy will provide new inspiration to improve the activity and stability of Pd/TiO2 catalysts for the hydrogenation of unsaturated polymers. [ABSTRACT FROM AUTHOR]

We here report the multicolor electrochemiluminescence (ECL) of binary microcrystals prepared from a blue‐emissive iridium complex 1 and an orange‐emissive ruthenium complex 2. These materials display a plate‐like morphology with high crystallinity, as demonstrated by microscopic and powder X‐ray diffraction analyses. Under light excitation, these microcrystals exhibit gradient emission color changes as a result of the efficient energy transfer between two complexes. When modified on glass carbon electrodes, these microcrystals exhibit tunable ECLs with varied emission colors including sky‐blue, white, orange, and red, depending on the doping ratio of complex 2 and the applied potential. Furthermore, organic amines with different molecular sizes are used as the co‐reactant to examine their influences on the ECL efficiency of the porous microcrystals of 1. The analysis on the luminance and RGB values of ECL suggests the existence of energy transfer in the generation of multicolor ECLs in these binary crystals. [ABSTRACT FROM AUTHOR]

The article explores the association of inflammatory skin biomarkers with clinical response in patients with hidradenitis suppurativa treated with RGRN-305, an HSP90 inhibitor. The study involved punch biopsies from patients participating in a randomized controlled trial, showing downregulation of inflammatory genes and pathways in responders to RGRN-305. Immunohistochemical staining revealed reduced inflammation in treated patients. The findings suggest that RGRN-305 may reduce inflammatory biomarkers in the skin, supporting its potential as a therapeutic strategy for hidradenitis suppurativa. [Extracted from the article]

Hardness decreases as indentation depth increases at both the nano- and micro-meter scales. By incorporating interfacial contributions, the indentation size effect can provide valuable information on the deformation behaviors of Ni-based single-crystal superalloys. In this paper, through experimental studies and atomistic simulations, we examine the indentation size effect and mechanical behaviors of Ni-based single-crystal superalloys. The results demonstrate that the indentation size effect, in conjunction with the Ni3Al/Ni interfacial network, is effectively captured by a modified Nix–Gao model. Molecular dynamics simulations further reveal the underlying atomistic mechanisms and microstructural evolution during nanoindentation. These findings provide new insights into the deformation behavior of Ni-based single-crystal superalloys and support their wide applications in the aerospace industry. [ABSTRACT FROM AUTHOR]

The effect of gravity based on the vector sum of gravity and buoyancy forces working spontaneously for all species was introduced into capillary electrophoresis (CE) as another important force which cooperated with electrophoretic flow and electro-osmotic flow. Their portion was adjusted by simply tilting the whole of the capillary at an angle during CE running. The related formula was proposed and verified through a series of experiments. After investigating the related parameters, results showed that the gravity effect was significantly affected by additives in the buffer, the length, and the inner diameter of the capillary, and the size of the sample molecule. This made the different ions with opposite or significantly different mobilities to be observed at a CE run. It significantly improved separation efficiencies of some small molecules, chiral compounds, macromolecules and cells when the tilt angles of the capillary were adjusted to a special range predicted through the fitting curve. In addition, micrometer level microspheres and cells were firstly separated by the new CE strategy and the resolutions were more than 1.0. After ingeniously designing the gradient of the tilting angle with time, we were able to further enhance the separation efficiency of the targets. For example, the resolution of lysozyme and ribonuclease A could be increased from 3.691 to 7.342. These indicated the huge potential of the new CE strategy and its gradient mode in separation. [ABSTRACT FROM AUTHOR]

Surface engineering in perovskite solar cells, especially for the upper surface of perovskite, is widely studied. However, most of these studies have primarily focused on the interaction between additive functional groups and perovskite point defects, neglecting the influence of other parts of additive molecules. Herein, additives with ‐NH3+ functional group are introduced at the perovskite surface to suppress surface defects. The chain lengths of these additives vary to conduct a detailed investigation into the impact of molecular size. The results indicate that the propane‐1,3‐diamine dihydroiodide (PDAI2), which possesses the most suitable size, exhibited obvious optimization effects. Whereas the molecules, methylenediamine dihydroiodide (MDAI2) and pentane‐1,5‐diamine dihydroiodide (PentDAI2) with unsuitable size, lead to a deterioration in device performance. The PDAI2‐treated devices achieved a certified power conversion efficiency (PCE) of 25.81% and the unencapsulated devices retained over 80% of their initial PCE after 600 h AM1.5 illumination. [ABSTRACT FROM AUTHOR]

Hydrosols containing tungsten(VI) oxide nanoparticles have been studied by the electrooptical and electrophoretic methods. The influence of multivalent ions (tetravalent thorium and trivalent lanthanum cations) on the zeta-potential and polarizability of tungsten(VI) oxide particles has been determined. The dispersion dependences of the polarizability of tungsten(VI) oxide particles have been studied. A strong dependence of the electrokinetic potential and a weak dependence of the polarizability of the particles on the concentrations of thorium and lanthanum cations in the sols have been found. The polarizability of the particles is low and weakly depends on the frequency of the field polarizing the particles. This is atypical for colloidal particles, for which the thickness of the dense part of the electrical double layer is comparable with the size of molecules, while the polarization of the electrical double layer is determined by its diffuse part. The obtained results have led to a conclusion that, for tungsten(VI) oxide particles in the studied concentration range, the majority of multivalent counterions are located in the dense part of the electrical double layer due to their high adsorption potential. [ABSTRACT FROM AUTHOR]

Dodecafluoropentane emulsion (DDFPe) is a fluorocarbon (FC) under clinical development as an oxygen therapeutic and is regulated as a blood substitute. Compared to all the prior FCs studied, DDFP is the most advantageous for oxygen delivery and it is active at a lower concentration (1/200th to 1/1000th the weight of other FCs). DDFP has a boiling point of 29 °C, is more water soluble than prior FCs, and following IV administration clears via exhalation. Prior FCs had boiling points ≥ 140 °C and were retained long-term in the body causing adverse events. DDFP is a gas at biological temperature while prior FCs were liquids. Gases deliver roughly 1000 times more oxygen than liquids. DDFPe has two mechanisms of action: (1) The size of the molecule is the smallest that is a liquid at room temperature; on a molar volume basis this equates to more dissolution of oxygen. (2) Because of its boiling point close to physiologic temperature, DDFP delivers oxygen more effectively than liquid FCs. Highlight Points: Fluorocarbons (FCs) dissolve oxygen and other respirable gases. FC emulsions generally do not have biological effects of and by themselves, but rather they increase the oxygen carrying capacity of the blood. There are a variety of FCs that were developed in the past as blood substitutes but they all caused accumulation in humans leading to toxic responses. Dodecafluoropentane emulsion (DDFPe) is being developed as an oxygen therapeutic to increase the oxygen carrying capacity of the blood and oxygen delivery to tissues. [ABSTRACT FROM AUTHOR]

Hydrogels like agarose have long been used as sieving media for the electrophoresis-based analysis of biopolymers. During gelation, the individual agarose strands tend to form hydrogen-bond mediated double-helical structures, allowing thermal reversibility and adjustable pore sizes for molecular sieving applications. The addition of tetrahydroxyborate to the agarose matrix results in transitional chemical cross-linking, offering an additional pore size adjusting option. Separation of SDS-proteins during gel electrophoresis is an activated process defined by the interplay between viscosity, gelation/cross-link formation/distortion, and sample conformation. In this paper, the subunits of a therapeutic monoclonal antibody were separated by capillary SDS agarose gel electrophoresis at different temperatures. The viscosity of the separation matrix was also measured at all temperatures. In both instances, Arrhenius plots were used to obtain the activation energy values. It was counterintuitively found that larger SDS–protein complexes required lower activation energies while their low-molecular-weight counterparts needed higher activation energy for their electromigration through the sieving matrix. As a first approximation, we considered this phenomenon the result of the electric force-driven distortion of the millisecond range lifetime reticulations by the larger and consequently more heavily charged electromigrating molecules. In the meantime, the sieving properties of the gel were still maintained, i.e., they allowed for the size-based separation of the sample components, proving the existence of the reticulations. Information about the activation energy sheds light on the possible deformation of the sieving matrix and the solute molecules. In addition, the activation energy requirement study helped in optimizing the separation temperature, e.g., with our sample mixture, the highest resolution was obtained for the high-molecular-weight fragments, i.e., between the non-glycosylated heavy chain and heavy-chain subunits at 25 °C (lower Ea requirement), while 55 °C was optimal for the lower-molecular-weight light chain and non-glycosylated heavy chain pair (lower Ea requirement). Future research directions and possible applications are also proposed. [ABSTRACT FROM AUTHOR]

By using the sessile drop method, the wetting properties of nonionic fluorocarbon surfactants (FNS-1 and FNS-2) and anionic fluorocarbon surfactant (FAS) solutions on the surface of polytetrafluoroethylene (PTFE) were investigated. Meanwhile, the effects of surfactant concentration on the contact angle, adhesion tension, PTFE–liquid interfacial tension, and work of adhesion of the fluorocarbon surfactant with different structures were detected. The results demonstrate that the adsorption amount of the three fluorocarbon surfactants at the air–liquid interface is 1.5~2 times higher than their adsorption amount at the PTFE–solution interface. Before critical micelle concentration (CMC), the fluorocarbon surfactant molecules rely on their hydrophobic groups to adsorb on the PTFE surface. The smallest molecular size of FNS-2 results in the largest adsorption amount, while electrostatic repulsion and large steric hindrance result in the smallest adsorption amount for FAS. Above CMC, the fluorocarbon surfactants form semi-micelles to adsorb on the PTFE surface. The hydrophilic modification ability of the three fluorocarbon surfactants for the PTFE surface is stronger than that of reported surfactants, and the contact angle can be reduced to about 20° at high concentrations. The order of the hydrophilic modification ability is FNS-2 > FNS-1 > FAS. Hydrophilic EO groups can effectively enhance the hydrophilicity of FNS-1 and FNS-2. Due to the hydrophobic -CH3 group and the smaller adsorption amount, FNS-1 possesses a weaker hydrophilic modification ability than FNS-2. Investigating the adsorption behavior of fluorocarbon surfactants on the PTFE surface can help us to better utilize fluorocarbon surfactants. This could have broad implications for colloid and interface science. [ABSTRACT FROM AUTHOR]

Collagen peptides play a crucial role in promoting skin elasticity and enhancing joint health, with potential functions to be explored. Enzyme hydrolysis is crucial for the molecular weight and sequence of peptides, influencing the bio-activity. In this study, the angiotensin-converting enzyme (ACE) inhibitory activity and fibroblast proliferation activity of differentially molecular weight peptides derived from dual- or triple-enzyme hydrolysis were compared. Ultrafiltration membrane filtration was used to separate the hydrolyzed prepared collagen peptides into two components based on the molecular size. The results showed that the low-molecular-weight peptide fraction containing peptides with P at the C-terminal, such as KP, RP, and POGP, exhibited high ACE inhibitory activity. The low-molecular-weight peptide fraction obtained through triple-enzyme hydrolysis incorporating ginger protease exhibited the highest ACE inhibitory activity, with an IC50 3.1 mg/mL. In addition, the triple-enzyme hydrolyzed collagen peptides passing across membranes displayed higher migration rates and enhanced collagen synthesis capabilities, containing peptide sequences, such as POGP, POGA, and LPO, potentially promoting fibroblast proliferation. The results would provide practical guidance for the production of collagen peptides with high ACE inhibitory activity and fibroblast proliferation activity, in terms of enzyme processing and highly active peptide separation. [ABSTRACT FROM AUTHOR]

Aromatic-aliphatic hydrocarbon separation is a challenging but important industrial process. Pervaporation membrane technology has the potential for separating these mixtures. We developed an oriented monolayer polyhedral (OMP) membrane that consists of a monolayer of ordered polyhedral particles and is anchored by hyper branched polymers. It contains a high density of straight, selective nano channels, enabling the preferential transport of aromatic molecules. Compared with traditional mixed-matrix membranes with random orientations, the OMP membrane improves the pervaporation separation index for aromatic-aliphatic hydrocarbon mixtures with C6 and C7 compounds, surpassing the performance of existing membranes by 3 to 10 times. This high performance demonstrates the potential of OMP membranes for hydrocarbon molecular separation and their application in the value-added separation of naphtha feedstocks. [ABSTRACT FROM AUTHOR]

A series of heterobimetallic (Au⋯Ag interlocking and Au⋯Cu interlocking) [2]catenanes were studied using DFT and TD-DFT methods to explore the relationship between their structures and properties. In order to fully investigate the influence of metal type in these [2]catenanes and compare the similarities and differences between these heterobimetallic and homometallic catenanes, the results were also compared with our previously studied homometallic Au⋯Au interlocking [2]catenane molecules. The results display that the steric hindrance increases with the increase of the number of monomers, and thus the distances between the center and the edge of the rings become longer, demonstrating a trend of outward expansion. As the size of the ring becomes larger, the total weak interaction increases and shows increasingly dispersed distribution. The value of the dispersion interaction energy increases with the overgrowth of the size of molecular systems and correspondingly the energy level of the frontier orbital decreases and the energy gap becomes bigger when two hexamers interlock. Compared with the Au⋯Ag interlocking [2]catenanes, the Au⋯Cu interlocking [2]catenanes present red-shifted absorption spectra, which is consistent with their smaller energy gap. The hole–electron analysis results indicate that the S0 → S1 excitations are almost unidirectional charge transfer excitations due to the significant separation of holes and electrons, while for the high-energy excited states, local excitations occupy a dominant position. Through the study of the specific proportion of charge transfer on each fragment in the main transition process, we found that for heterometallic [2]catenanes, the Cu atom in the Au⋯Cu interlocking [2]catenanes has a greater influence on the electronic structure. As for homometallic [2]catenanes, the effects of Au atoms in the two rings are equivalent on the electronic structure. [ABSTRACT FROM AUTHOR]

AbstractThe removal of carbon dioxide (CO2) from acetylene (C2H2) represents a pivotal industrial process for the production of high-purity C2H2. Nevertheless, the separation of C2H2 and CO2 is challenging due to their highly similar molecular sizes and physical properties. In this work, we report a fine regulation of a sql layered coordination polymer (termed NTU-107) into a rare fsc open framework (termed NTU-108) with naphthalenedisulphonic acid pillar for selective C2H2 capture from CO2-contained mixtures. NTU-107 was prepared by the reaction of 4-(1H-imidazol-1-yl)benzoic acid (L1) ligand and Cu2+ ion, showing a layered framework with a pore size of 4.2 Å. After inserting 1,5-naphthalenedisulphonic acid between the layers, a new pillar-layered open framework (5.8 Å) with sulphonic acid functional sites was prepared. Single-component gas adsorption experiments and breakthrough experiments demonstrated that NTU-108 with accessible sulphonic acid sites exhibits a high C2H2 absorption capacity and dynamic C2H2/CO2 separation performance at room temperature. [ABSTRACT FROM AUTHOR]

Renewable lubricant base oils derived from biomass can effectively mitigate environmental challenges while exhibiting exceptional properties. Herein, we propose a novel approach for the synthesis of ester-based and alkane-based renewable lubricant base oils, achieving an impressive yield of up to 99%. This strategy involves the utilization of methyl oleate and biomass-derived aromatics through two distinct chemistries: alkylation and alkylation followed by hydrodeoxygenation (HDO). Among the various Lewis acid catalysts screened, AlCl3 demonstrated superior performance and achieved a remarkable maximum yield of 99% for the alkylation product under the optimized reaction conditions. Subsequent hydrodeoxygenation (HDO) of these alkylation products using the Ir-ReOx/SiO2 catalyst resulted in the production of alkane-based lubricant base oils, with an impressive maximum yield of 96.3%. The molecular size and branching of ester-based and alkane-based products can be finely adjusted by employing diverse aromatic compounds during the alkylation process, thereby enabling tuning of their lubricant properties. The as-synthesized base oils exhibit superior properties to petroleum-derived group III base oils and demonstrate comparable performance to synthetic ester and PAO base oils. The presented strategy for synthesizing renewable base oils offers a sustainable alternative to petroleum-derived counterparts, thereby potentially mitigating greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Nanoporous solids, including metal-organic frameworks (MOFs), have long been known to capture small molecules by adsorption on their pore surfaces. Liquids are also known to accommodate small molecules by dissolution. These two processes have been recognized as fundamentally distinct phenomena because of the different nature of the medium—solids and liquids. Here, we report a dissolution-like gas accommodation so-called "adsorptive-dissolution" behavior in a MOF (PFAC-2) with pores densely filled with perfluoroalkyl chains. PFAC-2 does not have solvent-accessible voids; nevertheless, it captures oxygen molecules without changing the framework structure, analogous to molecular dissolution into liquids. Moreover, we demonstrate the selective capture of O2 by PFAC-2 in a mixture of O2 and Ar, which are difficult to separate due to their similarities such as boiling point and molecular size. Our results show the integration of molecular adsorption into nanospaces and dissolution into fluorous solvents, which can guide the design of crystalline adsorbents for selective molecular trapping and gas separation. A densely fluorinated nanospace demonstrates the integration of adsorption and dissolution, so-called "adsorptive-dissolution", which enables selective adsorption of O2 over Ar. [ABSTRACT FROM AUTHOR]

Given the negative fitness effects that pathogens impose on their hosts, the benefits of resistance should be universal. However, there is marked variation across plant species in the number of nucleotide-binding leucine-rich repeat receptors, which form a cornerstone of defense. The growth–defense trade-off hypothesis predicts costs associated with defense investment to generate variation in these traits. Our analysis comparing features of the intracellular immune-receptor repertoires with trait data of 187 species shows that in wild plants, the size of the molecular defense repertoire correlates negatively with growth. By contrast, we do not find evidence for a growth–defense trade-off in agricultural plants. Our cross-species approach highlights the central role of defense investment in shaping ecological trait variation and its sensitivity to domestication. [ABSTRACT FROM AUTHOR]

Glass transition is one of the most crucial physical properties for polymerical materials. As a typical complex polymerical material, the glass transition phenomenon in asphalt binder is directly related to their temperature-related properties. To investigate the glass transition characteristics, this study delves into the glass transition temperature of asphalt binder based on molecular dynamics simulations. It is found that the calculation range for the glass transition temperature sits between 100 and 400 K. The evolution of asphalt binder structure is influenced by different cooling rates, where lower cooling rates allow sufficient microstructural rearrangement, resulting in a smaller volume at the lower temperature. Model size is closely associated with the glass transition region. As the size increases, the transition region significantly expands. Increasing the model size also reduces volume fluctuations after isothermal relaxation, providing more stable volume changes. It is observed that higher cooling rates with a model size over 100 Å can well reproduce the glass transition process of asphalt binders. This work provides atomic-scale insights for the glass transition phenomenon in asphalt binder, which could be beneficial for the design of high-performance asphalt binder. [ABSTRACT FROM AUTHOR]

Botulinum toxin type A is a first-line treatment for post-stroke spasticity, with selective action at nerve endings and minimal effects beyond the injection site. However, concerns about potential adverse reactions due to toxin diffusion and spread can significantly influence physicians' therapeutic decisions in managing post-stroke spasticity. Current evidence shows that while the main formulations of botulinum toxin type A have different molecular weights and sizes, they do not exhibit differing diffusion profiles. Instead, the key factors determining botulinum toxin type A diffusion and spread in post-stroke spasticity management are the dose (i.e., the actual amount of 150 kDa neurotoxin protein injected), dilution, and injection volume. Other injection-related factors, such as the needle gauge and injection speed, have also been suggested to have a secondary influence on botulinum toxin type A diffusion and spread. The needs of patients with post-stroke spasticity may vary, and depending on treatment goals, botulinum toxin type A diffusion and spread can be something to avoid or may offer therapeutic benefits by reaching a greater number of nerve terminals in the target muscle, enhancing the toxin's effect. These factors should be carefully evaluated in spasticity clinics. [ABSTRACT FROM AUTHOR]

Background: Interferons (IFNs) are cytokines involved in the immune response with a synergistic regulatory effect on the immune response. They are therapeutics for various viral and proliferative conditions, with proven safety and efficacy. Their clinical application is challenging due to the molecules' size, degradation, and pharmacokinetics. We are working on new drug delivery systems that provide adequate therapeutic concentrations for these cytokines and prolong their half-life in the circulation, such as nanoformulations. Methods: Through nanoencapsulation using electrospray technology and biocompatible and biodegradable polymers, we are developing a controlled release system based on nanoparticles for viral infections of the respiratory tract. Results: We developed a controlled release system for viral respiratory tract infections. A prototype nanoparticle with a core was created, which hydrolyzed the polyvinylpyrrolidone (PVP) shell , releasing the active ingredients interferon-alpha (IFN-α) and interferon-gamma (IFN-γ). The chitosan (QS) core degraded slowly, with a controlled release of IFN-α. The primary and rapid effect of the interferon combination ensured an antiviral and immunoregulatory response from day one, induced by IFN-α and enhanced by IFN-γ. The multilayer design demonstrated an optimal toxicity profile. Conclusions: This formulation is an inhaled dry powder intended for the non-invasive intranasal route. The product does not require a cold chain and has the potential for self-administration in the face of emerging viral infections. This novel drug has applications in multiple infectious, oncological, and autoimmune conditions, and further development is proposed for its therapeutic potential. This prototype would ensure greater bioavailability, controlled release, fewer adverse effects, and robust biological action through the simultaneous action of both molecules. [ABSTRACT FROM AUTHOR]

The grain size of rice (Oryza sativa) plays a pivotal role in determining yield. It is crucial to explore the genes related to grain size and analyze their molecular mechanisms to enhance rice yield further. This study identified a small‐grain mutant small grain 12 (sg12), from the ethyl methanesulfonate‐induced mutant library of Shuhui 498, a backbone parent of heavy‐panicle hybrid rice. We found that sg12 rice mutant exhibits a decrease in grain size and 1000‐grain weight, but an increase in grain number per panicle. Genetic analysis indicated that the small grain of sg12 is controlled by a pair of semi‐dominant genes. Furthermore, cytological analysis showed that the number of longitudinal cells in the spikelet hull of sg12 decreased, indicating that SG12 regulates grain size by affecting cell proliferation. In this study, we also identified a candidate gene of SG12 as OsPPKL3, which encodes a putative protein phosphatase with Kelch‐like repeat domains. A single‐nucleotide polymorphism substitution (G/A) occurred in the conserved Kelch domain of OsPPKL3 in the sg12, resulting in the mutation of the 176th amino acid from Ala to Thr, and this amino acid substitution led to significant differences in the three‐dimensional structure of the OsPPKL3 protein. Finally, genetic analysis indicated that OsPPKL3 regulates grain size independent of Oryza sativa BRI1‐associated receptor kinase 1 (OsBAK1) and Oryza sativa Brassinosteroid‐signaling kinase 2 (OsBSK2). Overall, this study identified a new allelic mutant of OsPPKL3, clarified the cytological basis of OsPPKL3 regulating grain size, and emphasized the crucial role of the 176th amino acid in the Kelch domain of OsPPKL3 for its biological function. Our results provided important resources for further studying the molecular mechanisms of OsPPKL3 regulating grain size in rice. Core Ideas: Small grain 12 (sg12) is a new gain‐of‐function allele mutant of OsPPKL3.SG12/OsPPKL3 regulates grain size by affecting cell proliferation.A single‐nucleotide polymorphism (SNP) substitution (G/A) in the conserved Kelch domain of OsPPKL3 affected the protein structure of OsPPKL3.OsPPKL3 regulates grain size independent of Oryza sativa BRI1‐associated receptor kinase 1 (OsBAK1) and Oryza sativa Brassinosteroid‐signaling kinase 2 (OsBSK2).Our results provided important resources for further studying the molecular mechanisms of OsPPKL3. Plain Language Summary: The grain size of rice plays a pivotal role in determining yield. It is crucial to explore the genes related to grain size and analyze their molecular mechanisms to enhance rice yield further. This study identified a small‐grain mutant small grain 12 (sg12), and the small grain of sg12 is controlled by a pair of semi‐dominant genes. Cytological analysis showed that SG12 regulates grain size by affecting cell proliferation. We also identified a candidate gene of SG12 as OsPPKL3, which encodes a putative protein phosphatase with Kelch‐like repeat domains. A single‐nucleotide polymorphism substitution (G/A) occurred in the conserved Kelch domain of OsPPKL3 in the sg12, resulting in the mutation of the 176th amino acid from Ala to Thr, and this amino acid substitution led to significant differences in the three‐dimensional structure of the OsPPKL3 protein. Our results provided important resources for further studying the molecular mechanisms of OsPPKL3 regulating grain size in rice. [ABSTRACT FROM AUTHOR]

This study analyses JWST MIRI/MRS observations of the infrared (IR) polycyclic aromatic hydrocarbon (PAH) bands in the nuclear (∼0.4″ at 11 μm; ∼75 pc) and circumnuclear regions (inner ∼kpc) of local active galactic nuclei (AGNs) from the Galactic Activity, Torus, and Outflow Survey (GATOS). We examine the PAH properties in the circumnuclear regions of AGNs and the projected direction of AGN-outflows and compare them to those in star-forming regions and the innermost regions of AGNs. This study employs 4.9–28.1 μm sub-arcsecond angular resolution data to investigate the properties of PAHs in three nearby sources (DL ∼ 30 − 40 Mpc). Our findings are aligned with previous JWST studies, demonstrating that the central regions of AGNs display a larger fraction of neutral PAH molecules (i.e. elevated 11.3/6.2 and 11.3/7.7 μm PAH ratios) in comparison to star-forming galaxies. We find that AGNs might affect not only the PAH population in the innermost region, but also in the extended regions up to ∼kpc scales. By comparing our observations to PAH diagnostic diagrams, we find that, in general, regions located in the projected direction of the AGN-outflow occupy similar positions on the PAH diagnostic diagrams as those of the innermost regions of AGNs. Star-forming regions that are not affected by the AGNs in these galaxies share the same part of the diagram as star-forming galaxies. We also examined the potential of the PAH-H2 diagram to disentangle AGN-versus-star-forming activity. Our results suggest that in Seyfert-like AGNs, the illumination and feedback from the AGN might affect the PAH population at nuclear and kpc scales, particularly with respect to the ionisation state of the PAH grains. However, PAH molecular sizes are rather similar. The carriers of the ionised PAH bands (6.2 and 7.7 μm) are less resilient than those of neutral PAH bands (11.3 μm), which might be particularly important for strongly AGN-host coupled systems. Therefore, caution must be applied when using PAH bands as star-formation rate indicators in these systems even at kpc scales, with the effects of the AGN being more important for ionised ones. [ABSTRACT FROM AUTHOR]

In a bid to quantify the contribution of molecular structure to non-specific interactions leading to functionally important structural changes in cellular processes, the self-interaction of dextran-T70 (DT70) and its interaction with each of bovine serum albumin (BSA) and ovomucoid trypsin inhibitor (OVO) were studied at pH 7.4 between 5 and 37 °C. The dependences of the apparent molecular weight of each of BSA, OVO and DT70 on the concentration of DT70 were independent of temperature. The activity coefficient of the interaction of each species on DT70 concentration was also independent of temperature. The change in activity coefficient was however dependent on the molecular structure and size of the interacting species. The energy of insertion of each macromolecule in DT70 increased in the order DT70 > BSA > OVO. These findings show that although the enthalpic contribution is negligible, the extent of the entropic contribution to the macromolecular activity coefficient of interaction is chiefly the consequence of the exclusion volume of the interacting macromolecules. [ABSTRACT FROM AUTHOR]

DNA mixture analysis poses a significant challenge in forensic genetics, particularly when dealing with degraded and trace amount DNA samples. Multi-SNPs (MNPs) are genetic markers similar to microhaplotypes but with smaller molecular sizes (< 75 bp), making them theoretically more suitable for analyzing degraded and trace amount samples. In this case report, we investigated a cold case involving a campstool stored for over a decade, aiming to detect and locate the suspect's DNA. We employed both conventional capillary electrophoresis-based short tandem repeat (CE-STR) analysis and next-generation sequencing-based multi-SNP (NGS-MNP) analysis. The typing results and deconvolution of the mixed CE-STR profiles were inconclusive regarding the presence of the suspect's DNA in the mixed samples. However, through NGS-MNP analysis and presence probability calculations, we determined that the suspect's DNA was present in the samples from Sect. 4−1 with a probability of 1-8.41 × 10− 6 (99.999159%). This evidence contradicted the suspect's statement and aided in resolving the case. Our findings demonstrate the significant potential of MNP analysis for examining degraded and trace amount DNA mixtures in forensic investigations. [ABSTRACT FROM AUTHOR]