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This work shows that S-atom substitution in phosphate, controls the directionality of hole transfer processes between base and sugar-phosphate backbone in DNA systems. The investigation combines synthesis, electron spin resonance (ESR) studies in supercooled homogeneous solution, pulse radiolysis in aqueous solution at ambient temperature and density functional theory (DFT) calculations of in-house synthesized model compound dimethylphosphorothioate (DMTP(O(−))=S) and nucleotide (5’-O-methoxyphosphorothioyl-2’-deoxyguanosine (G-P(O(−))=S)). ESR investigations show that DMTP(O(−))=S reacts with Cl(2)(•−) to form the σ(2)σ*(1) adduct radical -P-S∸Cl which subsequently reacts with DMTP(O(−))=S to produce [-P-S∸S-P-](−). -P-S∸Cl in G-P(O(−))=S undergoes hole transfer to Gua forming the cation radical (G(•+)) via thermally activated hopping. However, pulse radiolysis measurements show that DMTP(O(−))=S forms the thiyl radical (-P-S•) by one-electron oxidation which did not produce [-P-S∸S-P-](−). Gua in G-P(O(−))=S is oxidized unimolecularly by -P-S• intermediate in sub-picosecond range. DFT thermochemical calculations explain the differences in ESR and pulse radiolysis results obtained at different temperatures.

The reactivity of electrons in the CO2-water system was evaluated through picosecond electron pulse radiolysis at different gas pressures (ranging from 1 to 118 bar) and temperatures (25 and 35C)...

This article deals with the problem of choosing the thickness of the heat-refl ecting screen behind the heating radiator, in which the conditions for the formation of condensate on the wall are not achieved. Based on the analysis of the results obtained, the maximum thickness of the screen is established, using the example of penofol, at the calculated temperature diff erence in the conditions of a cold fi ve-day period, and the heat losses and the economic eff ect of this energy-saving measure are determined already during the heating period. Calculations were carried out for a wall made of reinforced concrete, covered with plaster on the outside. This technique can be used for other cases of enclosing structures and various materials of the heat-refl ecting screen.

This article considers the incorporation of Prussians, Sudovians, and Scalovians who migrated to territories which were not theirs originally, into the social system of the State of the Teutonic Order between the 1280s and 1370s. The author examines the main aspects of this issue, i.e. property status and duties of migrants, with reference to data from 41 acts granted to them by the Order and the church, and the Chronicles written by Peter of Dusburg and Caspar Shuetz. The study of these data with the help of the prosopographical and historical and comparative methods makes it possible to determine the main directions of migration, number of migrants, size, and composition of their property and duties performed in relation to the Order and the church. The main regions for migration were Sambia and Pomesania, receiving 5 144 out of 5 166 persons. The choice of the regions was caused by the lack of local farmers that was the result of the devastation committed during the struggle of Prussians, Scalovians, and Sudovians with the expansion of the Order between 1260s and 1280s. Another reason was the remoteness of Sambia and Pomesania from the migrants’ native lands and the Grand Duchy of Lithuania. On the one hand, it prevented possible union between the settlers and the Lithuanian rulers and, on the other hand, fostered communication between the migrants and the Order which guaranteed the former status in the new community. The incorporation of Prussians, Scalovians, and Sudovians was carried out by granting them fief or locator’s office and implied the definition of their rights and duties similar to those enjoyed by the local inhabitants. The migrants served in the military, paid taxes, had jurisdiction over their peasants, added unclaimed lands to their property, received permission to fish in the nearby waters, etc. These features testify to the successful incorporation of migrants into the new social system that contributed to a further development of the State of the Teutonic Order., Статья посвящена инкорпорированию пруссов, судовов и скаловов, переселившихся на чужие для них территории, в социальную систему государства Тевтонского ордена в 1280–1370-е гг. Главные аспекты этой проблемы — имущественное положение и обязанности переселенцев — рассмотрены на основе сведений, содержащихся в 41 акте, выданном мигрантам Орденом и церковью, а также в хрониках Петра из Дусбурга и Каспара Шютца. Изучение данных сведений с помощью просопографического и сравнительно-исторического методов позволило определить основные направления миграции, численность переселенцев, размеры и состав их имущества, а также обязанности, выполняемые по отношению к Ордену и церкви. Основными областями для переселения стали Самбия и Помезания, где обосновались 5 144 из 5 166 мигрантов. Выбор этих земель был связан с нехваткой местных земледельцев, которая возникла вследствие разорения, совершенного в ходе борьбы пруссов, скаловов и судовов с экспансией Ордена в 1260–1280-е гг. Другой причиной стало географическое расположение Самбии и Помезании, находившихся вдали от родины переселенцев и Великого Литовского княжества. С одной стороны, это предотвращало возможный союз мигрантов с литовскими правителями, а с другой стороны — укрепляло их связь с Орденом, гарантировавшим положение в новых социумах. Инкорпорирование мигрантов происходило через пожалование лена или должности локатора, что подразумевало наделение их правами и обязанностями, аналогичными тем, которыми обладали местные жители. Переселенцы несли военную службу, выплачивали налоги, обладали юрисдикцией над своими крестьянами, включали в свою собственность выморочные земли, получали разрешение ловить рыбу в близлежащих водных угодьях и т. д. Данные особенности, свидетельствующие об успешном инкорпорировании мигрантов в новую социальную систему, способствовали дальнейшему развитию государства Тевтонского ордена.

Potęga Zakonu Krzyżackiego w Prusach opierała się głównie na włączaniu lokalnej ludności do jego systemu społecznego i gospodarczego w XIII i XIV wieku. Proces ten jaskrawo uwidocznił się w przypadku Prusów zamieszkujących Warmię, którzy zostali włączeni do służby Zakonowi i Kościołowi za nadania własności ziemi. Byli oni zobowiązani do służby wojskowej, budowy fortyfikacji i/lub płacenia podatków pieniężnych i naturalnych. Niektórzy z nich zakładali osady. Wśród właścicieli ziemskich występowały procesy kumulacji gruntów w rękach pojedycznych osób, niestabilne użytkowanie własności i przydzielanie działek mniej użytecznych, co było korygowane przez Zakon i Kościół za pomocą specjalnych środków: rozszerzania praw do dziedziczenia, odszkodowań dla własności ziemskiej, grzywny za zabójstwo właściciela ziemskiego (lennika) itp.

The article is devoted to the condition of lieges from Scalovia in the State of Teutonic Order, who possessed land estates of 2–6 hakens and were obliged to keep military service and built fortifications. Among representatives of this group, whose possessions were located mainly near the rivers Memel and Jura, there was accumulation of property and fragmentation of land estates. By stabilizing landholding, the Order could receive regular growing in number of lieges, that testified to successful incorporation of Scalovians in the new social system.

The reactivity of presolvated electrons with CO2 and N2O was studied in the gas pressure range of 1 to 52 bar. To measure this reactivity, a home-made spectroscopic cell with liquid circulation was developed which can work up to 70 bar of gas pressure. The efficiency of presolvated electron scavenging was determined from the decrease of the solvated electron yield after the application of a 5 ps electron pulse. In addition, the reaction rate between these molecules and solvated electrons was directly determined at gas pressures below the gas critical point, which is in agreement with those presented in the literature measured at gas pressures below

We consider a class of discrete Schrodinger operators on an infinite homogeneous rooted tree. Potentials for these operators are given by the coefficients of recurrence relations satisfied on a multidimensional lattice by multiple orthogonal polynomials. For operators on a binary tree with potentials generated by multiple orthogonal polynomials with respect to systems of measures supported on disjoint intervals (Angelesco systems) and for compact perturbations of such operators, we show that the essential spectrum is equal to the union of the intervals supporting the orthogonality measures.

Рассматривается класс дискретных операторов Шрeдингера на бесконечном однородном графе-дереве с корнем. Потенциалы операторов этого класса состоят из коэффициентов рекуррентных соотношений, которым на многомерной решетке удовлетворяют совместно ортогональные многочлены. Для операторов на бинарном дереве с потенциалами, генерируемыми совместно ортогональными многочленами по отношению к системе мер, заданных на непересекающихся отрезках (так называемой системе Анжелеско), а также для их компактных возмущений установлено, что существенный спектр совпадает с объединением отрезков - носителей мер ортогональности.

We consider weighted operators acting on $L^p({\mathbb{R}}^d)$ and show that they depend continuously on the weight $w\in A_p({\mathbb{R}}^d)$ in the operator topology. Then, we use this result to estimate $L^p_w({\mathbb{T}})$ norm of polynomials orthogonal on the unit circle when the weight $w$ belongs to Muckenhoupt class $A_2({\mathbb{T}})$ and $p>2$. The asymptotics of the polynomial entropy is obtained as an application.

International audience; Selective and sensitive detection of Cu(I) is an ongoing challenge due to its important role in biological systems, for example. Herein, we describe a photoluminescent molecular chemosensor integrating two lanthanide ions (Tb$^{3+}$ and Eu$^{3+}$) and respective tryptophan and naphthalene antennas onto a polypeptide backbone. The latter was structurally inspired from copper-regulating biomacromolecules in Gram-negative bacteria and was found to bind Cu$^+$ effectively under pseudobiological conditions (log K$_{Cu}$$^+$ = 9.7 ± 0.2). Ion regulated modulation of lanthanide luminescence in terms of intensity and long, millisecond lifetime offers perspectives in terms of ratiometric and time-gated detection of Cu$^+$. The role of the bound ion in determining the photophysical properties is discussed with the aid of additional model compounds.

Metal nanoparticles can catalyze reactions involving organic free radicals. From the first studies focused on the catalytic reduction of water by free radicals until today, the catalytic oxidation of organic radicals has not received attention. In this work, we present the results on the catalytic activity of gold nanoparticles in the oxidation of 2-propanol to acetone and acetanilide hydroxylation during water radiolysis. A detailed reaction mechanism of α-hydroxyisopropyl radical oxidation is discussed, explaining the increase in acetone formation by ca. 340% in the presence of gold nanoparticles. In the case of acetanilide hydroxylation in the presence of nanoparticles, a strong effect of oxygen in the reaction mechanism was observed: the increase in the oxygen concentration from 0 to 1.22 mM leads to a 40-fold decrease in hydroxylation product formation. This observation is unexpected since, in the absence of gold nanoparticles, oxygen stimulates hydroxylation reactions. We propose that in the presence of both oxygen and nanoparticles, oxygen attaches first to acetanilide OH-adducts, and then nanoparticles catalyze the oxidation of peroxyl type radicals, which does not lead to the formation of hydroxylation products.

The article describes unusual caval-portal anastomosis via paraumbilical veins, which has resulted in the hepatic pseudolesion around the falciform ligament. We present a case of a 41-year-old male diagnosed with superior vena cava syndrome. Abdominal CT identified hypervascular pseudolesion from the Sappey superior veins.

We obtain generalizations of the classical Menchov–Rademacher theorem to the case of continuous orthogonal systems. These results are applied to show the existence of Moller wave operators in Schrödinger evolution.

In the present work, the impact of the rhodium deposition on the thermal stability of ceria-based catalysts was studied. The samples were prepared by an incipient wetness impregnation of the support with aqueous solution of rhodium nitrate. The loading of Rh was 0.1 and 1 wt.%. The textural characteristics of the samples were examined by a low-temperature nitrogen adsorption. It was shown that the addition of rhodium intensifies the process of ceria agglomeration, which leads to the lower values of specific surface area along with increased average pore diameter after the aging at 1000 °C. Stability of the catalysts was investigated by means of a prompt thermal aging procedure. The high-loaded catalyst (1 wt.% Rh/CeO2) was more active than the 0.1 wt.% Rh/CeO2sample, while the stability of both the catalysts was excellent. It should be emphasized that the alumina-based reference samples with the similar rhodium loading were significantly less active and poorly stable.

The early mechanisms by which ionizing rays damage biological structures by so-called direct effects are largely elusive. In a recent picosecond pulse radiolysis study of concentrated uridine monophosphate solutions [J. Ma, S. A. Denisov, J.-L. Marignier, P. Pernot, A. Adhikary, S. Seki and M. Mostafavi, J. Phys. Chem. Lett., 2018, 9, 5105], unexpected results were found regarding the oxidation of the nucleobase. The signature of the oxidized nucleobase could not be detected 5 ps after the electron pulse, but only the oxidized phosphate, raising intriguing questions about the identity of charge-transfer mechanisms that could explain the absence of U+. We address here this question by means of advanced first-principles atomistic simulations of solvated uridine monophosphate, combining Density Functional Theory (DFT) with polarizable embedding schemes. We contrast three very distinct mechanisms of charge transfer covering the atto-, femto- and pico-second timescales. We first investigate the ionization mechanism and subsequent hole/charge migrations on a timescale of attoseconds to a few femtoseconds under the frozen nuclei approximation. We then consider a nuclear-driven phosphate-to-oxidized-nucleobase electron transfer, showing that it is an uncompetitive reaction channel on the sub-picosecond timescale, despite its high exothermicity and significant electronic coupling. Finally, we show that non-adiabatic charge transfer is enabled by femtosecond nuclear relaxation after ionization. We show that electronic decoherence and the electronic coupling strength are the key parameters that determine the hopping probabilities. Our results provide important insight into the interplay between electronics and nuclear motions in the early stages of the multiscale responses of biological matter subjected to ionizing radiation.

Substitution of the thymidine moiety in DNA by C5-subsituted halogenated thymidine analogs causes significant augmentation of radiation damage in living cells. However, the molecular pathway involved in such radiosensitization process has not been clearly elucidated to date in solution at room temperature. So far, low-energy electron (LEEs; 0–20 eV) under vacuum condition and solvated electrons (e(sol)(−)) in solution are shown to produce the σ-type C5-centered pyrimidine base radical through dissociative electron attachment involving carbon-halogen bond breakage. Formation of this σ-type radical and its subsequent reactions are proposed to cause cellular radiosensitization. Here, we report time-resolved measurements at room temperature showing that a radiation-produced quasi-free electron (e(qf)(−)) in solution promptly breaks the C5-halogen bond in halopyrimidines forming the σ-type C5 radical via an excited transient anion radical. These results demonstrate the importance of ultrafast reactions of e(qf)(−) which are extremely important in Chemistry, Physics, and Biology, including tumor radiochemotherapy.

International audience; Due to their similar coordination properties, discrimination of Cu + and Ag + by water-soluble luminescent probes is challenging. We have synthesized LCC4 Eu , an 18 amino acid cyclic peptide bearing a europium complex, that is able to bind one Cu + or Ag + ion by the side chains of two methionines, a histidine and a 3-(1-naphthyl)-Lalanine. In this system, the naphthyl moiety establishes a cation- interaction with these cations. It also acts as an antenna for the sensitization of Eu 3+ luminescence. Interestingly, when excited at 280 nm behaves as a turn-on probe for Ag + (+150 % Eu emission) and as a turn-off probe for Cu + (-50% Eu 3+ emission). Shifting the excitation wavelength to 305 nm makes the probe responsive to Ag + (+380% Eu 3+ emission) but not to Cu + or other physiological cations. Thus, LCC4 Eu is uniquely capable of discriminating Ag + from Cu +. A detailed spectroscopic characterization based on steady state and time-resolved measurements clearly demonstrates that Eu 3+ sensitization relies on electronic energy transfer from the naphthalene triplet state to the Eu 3+ excited states and that the cation- interaction lowers the energy of this triplet state by 700 cm-1 and 2400 cm-1 for Ag + and Cu + , respectively. Spectroscopic data point to a modulation of the efficiency of the electronic energy transfer caused by the differential red-shift of the naphthalene triplet, deciphering the differential luminescence response of LCC4 Eu toward Ag + and Cu + .

The present study proposes a new approach for direct CO 2 conversion using primary radicals from water irradiation. In order to ensure reduction of CO 2 into CO 2 •- by all the hydrated electrons, we use formate ions to scavenge simultaneously the parent oxidizing radicals H • and OH • producing the same transient CO 2 •- radicals. Conditions are optimized to obtain the highest conversion yield of CO 2 . The goal is achieved under mild conditions of room temperature, neutral pH and 1 atm of CO 2 pressure. All the available radicals are exploited for selectively converting CO 2 into oxalate that is accompanied by H 2 evolution. Besides, at high CO 2 pressure, CO is also produced via presolvated electron scavenging and the H • radicals with CO 2 •- . The mechanism presented accounts for the results and also sheds light on the data in the literature. The radiolytic approach is a mild and scalable route of direct CO 2 capture at the source in industry and the products, oxalate salt and H 2 , can be easily separated.

The present study proposes a new approach for direct CO

The excess electron in solution is a highly reactive radical involved in various radiation-induced reactions. Its solvation state critically determines the subsequent pathway and rate of transfer. For instance, water plays a dominating role in the electron-induced dealkylation of n-tributyl phosphate in actinide extraction processing. However, the underlying electron solvation processes in such systems are lacking. Herein, we directly observed the solvation dynamics of electrons in H-bonded water and n-tributyl phosphate (TBP) binary solutions with a mole fraction of water (Xw) varying from 0.05 to 0.51 under ambient conditions. Following the evolution of the absorption spectrum of trapped electrons (not fully solvated) with picosecond resolution, we show that electrons statistically distributed would undergo preferential solvation within water molecules extracted in TBP. We determine the time scale of excess electron full solvation from the deconvoluted transient absorption-kinetical data. The process of solvent reorganization accelerates by increasing the water molar fraction, and the rate of this process is 2 orders of magnitude slower compared to bulk water. We assigned the solvation process to hydrogen network reorientation induced by a negative charge of the excess electron that strongly depends on the local water environment. Our findings suggest that water significantly stabilizes the electron in a deeper potential than the pure TBP case. In its new state, the electron is likely to inhibit the dealkylation of extractants in actinide separation.

Numerous additives are used in the electrolytes of lithium-ion batteries, especially for the formation of an efficient solid electrolyte interphase at the surface of the electrodes. Understanding the degradation processes of these compounds is thus important; they can be seen through radiolysis. In the case of fluoroethylene carbonate (FEC), picosecond pulse radiolysis experiments evidenced the formation of FEC.- . This radical is stabilized in neat FEC, whereas the ring opens to form more stable radical anions when FEC is a solute in other solvents, as confirmed by quantum chemistry calculations. In neat FEC, pre-solvated electrons primarily undergo attachment rather than solvation. On long timescales, the gases produced (H2 , CO, and CO2 ) were quantified. A reaction scheme for both the oxidizing and reducing pathways at stake in irradiated FEC is proposed. This work shows that the nature of the primary species formed in FEC depends on the amount of FEC in the solution.

International audience; Imogolite nanotubes are potentially promising co-photocatalysts because they are predicted to have curvature-induced, efficient electron-hole pair separation. This prediction has however not yet been experimentally proven. Here, we investigated the behavior upon irradiation of these inorganic nanotubes as a function of their water content to understand the fate of the generated electrons and holes. Two types of aluminosilicate nanotubes were studied: one was hydrophilic on its external and internal surfaces (IMO-OH) and the other had a hydrophobic internal cavity due to Si-CH$_3$ bonds (IMO-CH$_3$), with the external surface remaining hydrophilic. Picosecond pulse radiolysis experiments demonstrated that the electrons are efficiently driven outward. For imogolite samples with very few external water molecules (around 1% of the total mass), quasi-free electrons were formed. They were able to attach to a water molecule, generating a water radical anion, which ultimately led to dihydrogen. When more external water molecules were present, solvated electrons, precursors of dihydrogen, were formed. In contrast, holes moved towards the internal surface of the tubes. They mainly led to the formation of dihydrogen and of methane in irradiated IMO-CH$_3$. The attachment of the quasi-free electron to water was a very efficient process and accounted for the high dihydrogen production at low relative humidity values. When the water content increased, 2 electron solvation dominated over attachment to water molecules. Electron solvation led to dihydrogen production, albeit to a lesser extent than quasi-free electrons. Our experiments demonstrated the spontaneous curvature-induced charge separation in these inorganic nanotubes, making them very interesting potential co-photocatalysts.

International audience; Nucleation and growth of crystallites are induced by the shockwave of a single laser nanosecond pulse in highly supersaturated solutions of potassium nitrate (saltpeter). The kinetics of the turbidity resulting from the light scattering by the growing crystals is observed by time-resolved optical spectroscopy. With an optical path of 10 mm, we first focused on the early part of the growth under various conditions, but it is limited by the detection system to a few percent of the total growth. Remarkably, in this domain and for all supersaturated concentrations studied, the turbidity increases proportionally with time. This zero-order process with an accretion rate constant (k = 4.7 × 107 L mol–1 s–1) implies that the nuclei and growing crystals’ concentration remain constant. This concentration is determined from the final diameter of crystals that are observed to have a bipyramidal shape by transmission electron microscopy (TEM). Moreover, the number of accretion sites per crystal must be constant in this time range and they are identified as the apexes. In complement, the kinetics detected with shorter optical paths permits us to observe larger parts of the total growth (up to 35% with 1 mm of optical path). In this case, after the linear part, the turbidity increase is markedly accelerated, indicating that the number of accretion sites per crystal increases rapidly with the crystal size and that the edges and facet sites also fix the molecules. The complete analysis by a homogeneous kinetics model of the signals obtained under various conditions concludes to an anisotropic growth of the crystals with another accretion rate constant (k′ = 100 L mol–1 s–1) that is much lower on these edges and facet sites than on the apexes. However, this contribution becomes predominant only when the crystals develop to a larger size.

We collect several applications of a new version of the classical Szegő formula for orthogonal polynomials. The applications are concerned with the spectral theory of Krein strings, scattering theory for Dirac systems, and triangular factorizations of positive Wiener–Hopf operators.

Krein–de Branges spectral theory provides a correspondence between canonical Hamiltonian systems and measures on the real line with finite Poisson integral. We revisit this area by giving a description of canonical Hamiltonian systems whose spectral measures have logarithmic integral converging over the real line. Our result can be viewed as a spectral version of the classical Szegő theorem in the theory of polynomials orthogonal on the unit circle. It extends Krein–Wiener completeness theorem, a key fact in the prediction of stationary Gaussian processes.

We investigate the oxidation of silver cyanide AgI(CN)2- in water by the OH radical in order to compare this complex with the free cation Ag+ and to measure the influence of the ligands. High-level ab initio calculations of the model species AgII(CN)2· enable the calibration of molecular simulations and the prediction of the oxidized species: AgII(CN)2(H2O)2· and its absorption spectrum, with an intense band at 292 nm and a weaker one at 390 nm. Pulse radiolysis measurements of the oxidation of AgI(CN)2- by the OH radical in water yields a transient species with a broad, intense band at 290 nm and a weaker band at 410 nm at short times after the pulse and a blue shift of the spectrum at longer times. The prediction of the simulations, that the oxidized complex AgII(CN)2(H2O)2· is formed, is confirmed by thermochemistry. Our calculations also suggest that the formation of the OH-adduct is possible only in very basic solution and that the blue shift observed at long times after the pulse is due to disproportionation of the oxidized complex. We also perform molecular simulations of the oxidation of free Ag+ cations by the OH radical. The results are compared to that of the literature and to the results obtained with the AgI(CN)2- complex.

We investigate the oxidation of silver cyanide