Search

The vibration-rotation absorption spectrum of 17O-enriched water vapor in the range 14900–15600 cm−1 was recorded for the first time by a Fourier Transform Spectrometer coupled to a multi-pass White-type cell providing an optical path length of 34.8 m at room temperature with a spectral resolution of 0.05 cm−1 using high luminance LED (light emitting diode) light source. The high signal-to-noise ratio allowed for the accurate determination of 1047 positions of water lines, of which 661 lines were attributed to the H217O water isotopologue. The rovibrational assignment was based on new variational calculations, which allowed retrieving 285 experimental rotational-vibrational energy levels belonging to twelve vibrational states of the H217O molecule: (410), (330), (311), (231), (212), (151), (033), (052), (113), (132), (180), and (081). The 3ν1+ν2+ν3, 2ν1+3ν2+ν3 and 4ν1+ν2 vibrational bands centered, respectively, at 15325.617, 15095.166 and 15322.533 cm−1, dominate the spectrum. A detailed comparison of the H217O line intensities recorded in this study with observed literature data and with recent high-precision variational calculations showed that the calculated intensities for the (231) - (000) band are weaker by 57% than the experimental ones. The data set obtained in this study will help to improve the quality of variational calculations for water vapor.

To assess the possibility of using the integral indicators of thrombodynamics to improve the safety of rehabilitation measures in patients in the recovery period of stroke.A prospective study included 52 patients in the recovery period of stroke. To compare the effect of the intensity of physical activity on the change in the integral indicators of thrombodynamics in accordance with the objectives of the study, the patients were randomized into two groups. In the first group, patients received treatment, including physiotherapy, stabilometric trainings, neuropsychological tasks. Patients of the second group received complex treatment, including more intense physical activity with the use of cyclic exercises, biomechanotherapy. To assess the state of hemostasis, an integral thrombodynamics test was used, and the numerical parameters of the spatial dynamics of the growth of a fibrin clot were calculated.The state of compensated hypercoagulability was revealed in the majority of patients before the start of medical rehabilitation, despite taking antithrombotic therapy, which was evidence of the ineffectiveness of the therapy. At the same time, it was noted that it was its action, probably during the ongoing program of physical rehabilitation, that ensured the stability of the integral indicators of thrombodynamics and the absence of clinically significant unwanted thromboembolic complications. As a result of the analysis of the data in dynamics before and after treatment, a direct relationship was traced between the intensity of physical activity and the tendency to disturb the hemostatic balance.The intensity of physical activity during treatment undoubtedly influenced the state of hemostasis. The expediency of monitoring the dynamics of coagulation activity in patients in the recovery period of stroke has been demonstrated.Оценка возможности использования интегральных показателей тромбодинамики для повышения безопасности проведения реабилитационных мероприятий у пациентов в восстановительном периоде церебрального инсульта.В проспективное исследование включены 52 пациента в восстановительном периоде инсульта. Методом простой рандомизации пациенты были разделены на две группы в соответствии с задачами исследования: сравнить влияние интенсивности физических нагрузок на изменение интегральных показателей тромбодинамики. В первой группе больные получали лечение, включающее физиотерапию, стабилометрические тренинги, нейропсихологические задания. Пациенты второй группы получали комплексное лечение, включающее более интенсивные физические нагрузки с использованием роботизированной биомеханотерапии. Для оценки состояния гемостаза использовали интегральный тест тромбодинамики, рассчитывали численные параметры пространственной динамики роста фибринового сгустка.В нашей работе было выявлено состояние компенсированной гиперкоагуляции у большинства больных до начала мероприятий медицинской реабилитации, несмотря на прием антитромботической терапии, что является свидетельством неэффективности проводимого лечения. При этом отмечено, что, вероятно, именно действие антитромботической терапии обеспечило стабильность интегральных показателей тромбодинамики и отсутствие клинически значимых нежелательных тромбоэмболических осложнений в ходе проводимой программы физической реабилитации. В результате анализа данных до и после лечения была прослежена прямая зависимость между интенсивностью физической нагрузки и тенденцией к нарушению гемостатического баланса.В результате проведенного исследования было выявлено, что интенсивность физических нагрузок в ходе лечения оказывала влияние на состояние гемостаза. Продемонстрирована целесообразность мониторинга динамики коагуляционной активности у пациентов в восстановительном периоде инсульта.

The spectrum of HD16O vapor has been recorded between 14,800 and 15,500 cm-1 by a Fourier transform spectrometer with a spectral resolution of 0.05 cm-1 using a high luminance LED light source and a 60-cm multipath cell with a path length of 3480 cm. A high signal-to-noise ratio (S/N ≈ 10,000) has allowed us to record the lines with intensities of 1.0 × 10-24 to 1.0 × 10-27 cm/molecule. More than 740 lines have been recorded in the spectrum of natural abundance water vapor and over 1210 lines in the spectrum of the vapor enriched with D. 316 rotation-vibration energy levels of the HD16O molecule have been assigned to nine vibrational states. The majority of these energies was attributed to the (014), (600), (142) and (302) states. One hundred two energy levels have been obtained for the first time. The recorded spectra have been compared with the simulations based on the HITRAN-2016 database and variational lists.

The absorption spectrum of water vapor enriched by deuterium and oxygen-18 is analyzed in the 6000–9200 cm−1 region. The spectrum has been recorded at room temperature with a Bruker IFS 120 h Fourier transform spectrometer. More than 14,000 absorption lines were measured in the recorded spectrum. The vibration–rotation assignments were performed on the basis of previously published experimental energies and of variational calculations. Nine water species (H216O, HD16O, D216O, H218O, HD18O, D218O, H217O, HD17O and D217O) were found to contribute to the observed absorption. More than 3600 lines of 19 vibrational bands of D218O and about 4700 lines of 16 bands of HD18O with J as high as 19 and Ka as high as 11 were assigned. The main part of the HD18O and D218O lines and all lines of HD17O and D217O were observed in the laboratory for the first time. The obtained vibration–rotation energy levels are compared with previous experimental studies and the results of variational calculations.

High-resolution Fourier-transform spectra of water samples enriched by deuterium and oxygen-18 at room temperature are analyzed in the range 969–2148 cm−1. Line positions of about 2470 transitions up to Jmax = 22 and Ka max = 12 of the ν2 bands of the HD18O and D 2 18 O molecules are reported. This has allowed the determination of extended sets of rotational energies of the (0 0 0) and (0 1 0) vibrational states for both molecules. The generation function model of an effective rotational Hamiltonian was used in the data reduction to account for the strong centrifugal distortion of the rotational levels. Values of effective Hamiltonian parameters have been determined. The RMS standard deviations of the least-squares fits of the energy levels were 2.4 × 10−4 cm−1 for 293 energy levels of the ground state and 3.2 × 10−4 cm−1 for 281 energy levels of the (010) state of D 2 18 O , and 2.6 × 10−4 cm−1 for 227 energy levels of the ground state and 4.2 × 10−4 cm−1 for 246 energy levels of the (0 1 0) state of HD18O. Comparisons of obtained data with the theoretical predictions as well as with other observations are presented.

The weak absorption spectrum of monodeuterated water, HDO, has been recorded by intracavity laser absorption spectroscopy (ICLAS) between 11 645 and 12 330 cm −1 . This spectrum is dominated by the ν 2 + 3 ν 3 band of HDO at 11969.76 cm −1 . A total of 497 energy levels belonging to 12 vibrational states were determined while only 140 levels were previously reported from a recent investigation by Fourier transform spectroscopy in the same spectral region. The rovibrational identification process of the 1378 lines assigned to the HDO isotopologue was mostly based on the results of the accurate variational calculations of Schwenke and Partridge. The overall agreement between these calculations and the observed spectrum is very good. However, strong discrepancies in the calculated line intensities were evidenced in a few cases corresponding to an intensity transfer to a dark state through local resonance interaction.

This paper is the fourth of a series of papers reporting critically evaluated rotational–vibrational line positions, transition intensities, pressure dependences, and energy levels, with associated critically reviewed assignments and uncertainties, for all the main isotopologues of water. This paper presents energy level and transition data for the following doubly and triply substituted isotopologues of water: D216O, D217O, and D218O. The MARVEL (Measured Active Rotational–Vibrational Energy Levels) procedure is used to determine the levels, the lines, and their self-consistent uncertainties for the spectral regions 0–14 016, 0–7969, and 0–9108 cm−1 for D216O, D217O, and D218O, respectively. For D216O, D217O, and D218O, 53 534, 600, and 12 167 lines are considered, respectively, from spectra recorded in absorption at room temperature and in emission at elevated temperatures. The number of validated energy levels is 12 269, 338, and 3351 for D216O, D217O, and D218O, respectively. The energy levels have been checked against the ones determined, with an average accuracy of about 0.03 cm−1, from variational rovibrational computations employing exact kinetic energy operators and an accurate potential energy surface. Furthermore, the rovibrational labels of the energy levels have been validated by an analysis of the computed wavefunctions using the rigid-rotor decomposition (RRD) scheme. The extensive list of MARVEL lines and levels obtained is deposited in the Supplementary Material of this paper, in a distributed information system applied to water, W@DIS, and on the official MARVEL website, where they can easily be retrieved.

The weak absorption spectrum of dideuterated water, D2O, has been recorded between 12450 and 12850 cm(-1) by high sensitivity. Intracavity Laser Absorption Spectroscopy (ICLAS). This spectral region corresponds to the (nu(1) + nu(2)/2 + nu(3)) = 5 polyad, dominated by the 4 nu(1) + nu(3) band centered at 12743.035 cm(-1). The achieved sensitivity has allowed for the detection of lines with a minimum intensity of 2 x 10(-28) cm/molecule i.e. typically two orders of magnitude lower than previous observations in the region considered. A total of 586 energy levels belonging to I I vibrational states were determined. The rovibrational assignment process of 1025 lines ascribed to D20 was based on new results of variational calculations by Shirin et al. [S.V. Shirin, N.F. Zobov, O.L. Polyansky, J. Quant. Spectrosc. Radiat. Transfer, in press, doi:10.1016/j.jqsrt.2007.07.010]. The overall agreement between these calculations and the observed spectrum is good both for the line positions and line intensities. The difficulties encountered while performing the rovibrational labeling and the assignment of the weakest transitions not included in Combination Differences relations, are discussed. (c) 2007 Elsevier Inc. All rights reserved.

1. A new NMR approach is described for the investigation of transbilayer asymmetry in phospholipid vesicles consisting of phosphatidylcholine and negatively charged phospholipids. The method makes use of the dependence of the psuedocontact shift of the N-methyl proton resonance induced by paramagnetic ions on the surface concentration of negatively charged phospholipids. When two differently shifting paramagnetic probes are applied from the outside and the inside of a vesicular membrane the transbilayer phospholipid distribution can be estimated without knowledge of the inner and outer radii of the vesicles and the packing density of the phospholipid molecules. 2. The method was employed to study the transbilayer asymmetry in vesicles obtained by cosonication of phosphatidylcholine with phosphatidylserine, phosphatidylglycerol or phosphatidylinositol. The three negative phospholipids were found to distribute with a higher surface concentration in the inner vesicular shell than in the outer one when their total content did not exceed 25 mol%. However, as the amount of negatively charged phospholipids increases the ratio of their inside to outside surface concentrations, i.e., the transbilayer asymmetry of the vesicles, decreases. Prolonged incubation (for several days) does not change the compositional asymmetry of the cosonicated vesicles. 3. By the 'double-probe' technique it was established that spontaneous exchange between separately sonicated phosphatidylcholine and phosphatidylinositol vesicles results in formation of highly asymmetric mixed vesicles with phosphatidylinositol residing only in the outer monolayer. In the presence of antioxidant (alpha-tocopherol) the bilayer asymmetry is preserved for days. However lipid peroxidation induces rapid transbilayer movement (flip-flop) of phospholipids leading to an 'inverted' asymmetry resembling that of cosonicated vesicles. It is suggested that lipid peroxidation promotes phospholipid flip-flop by partially converting the bilayer structure into a non-bilayer configuration. Moderate quantities of lysophosphatidylcholine (up to 15 mol%) induce neither detectable perturbations of the bilayer nor rapid phospholipid flip-flop.