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1

Neugebauer, Petr, and Anne-Laure Barra. "New Cavity Design for Broad-Band Quasi-Optical HF-EPR Spectroscopy." Applied Magnetic Resonance 37, no. 1-4 (November 16, 2009): 833–43. http://dx.doi.org/10.1007/s00723-009-0092-5.

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2

Donaldson, L., and A. Frankland. "Ultrastructure of iodine treated wood." Holzforschung 58, no. 3 (May 12, 2004): 219–25. http://dx.doi.org/10.1515/hf.2004.034.

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Abstract Iodine staining has been used to study the orientation of cellulose microfibrils in wood using light microscopy. The aim of this work was to understand the exact nature of the staining reaction with iodine and to provide insight into the properties and organisation of the wood cell wall. Based on transmission electron microscopy it is apparent that precipitation of the iodine following treatment with nitric acid results in the formation of crystal cavities within the cell wall, which follow the orientation of the cellulose microfibrils. There is no evidence that iodine precipitates within “drying checks” as previously speculated. High resolution confocal reflectance microscopy of crystal cavity orientation indicates that the microfibril arrangement within pit borders can be both spiral and circular. Crystal cavities are much more abundant within the S1 layer than elsewhere. All of the cells examined had crystal cavities in the S1 region, which may be related to the reduced lignification at the S1/S2 boundary resulting in greater porosity of the cell wall at this location. Within the S2 region, clusters of crystal cavities are randomly distributed and occur in widely varying numbers among adjacent cell walls, suggesting variations in the porosity of the S2 wall within and among adjacent tracheids. Cavities form preferentially within more electron lucent regions of the cell wall. The random nature of crystal cavity formation within S2 clusters probably reflects the underlying random nature of the cell wall nanostructure. We conclude that iodine staining can provide important clues to the nanostructural properties of tracheid cell walls.
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3

Zhang, Yuanhai, Xingang Wang, Yuezhen Liu, Xinhua Jiang, Chunjiang Ye, Liangfang Ni, Liping Zhang, Jianfen Zhang, Bin Xu, and Chunmao Han. "Management of a Rare Case With Severe Hydrofluoric Acid Burns: Important Roles of Neutralizers and Continuous Renal Replacement Therapy." International Journal of Lower Extremity Wounds 16, no. 4 (November 13, 2017): 289–95. http://dx.doi.org/10.1177/1534734617736198.

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Анотація:
Hydrofluoric acid (HF), a dangerous inorganic acid, is widely used in various industries and in daily life. Chemical burns caused by HF exposure occur more frequently in some regions worldwide. It has been reported that some cases with HF burns can be lethal due to the hypertoxicity of HF. In this article, we present a case of a 24-year-old worker who suffered HF burns by 53% HF solution to his face, neck, and nasal cavity. This patient quickly developed electrolyte disturbance, that is, hypocalcemia, and hypopotassemia, and myocardial injury after exposure. Multiple measures had been taken to treat this patient, including fluid resuscitation, electrolyte replacement, timely wound treatment with neutralizers, and respiratory tract care. Moreover, continuous renal replacement therapy was also employed to remove fluoride in the circulatory system and rectify the electrolyte disturbance and acid-base imbalance. The patient smoothly pulled though and survived. High fluoride levels in the dialysate solution were confirmed, indicating that continuous renal replacement therapy is an effective and potentially lifesaving treatment for acute HF poisoning.
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4

Li, Wanju, Minghui Liu, Hankun Wang, and Yan Yu. "Fabrication of highly stable and durable furfurylated wood materials. Part II: the multi-scale distribution of furfuryl alcohol (FA) resin in wood." Holzforschung 74, no. 12 (November 18, 2020): 1147–55. http://dx.doi.org/10.1515/hf-2019-0287.

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AbstractThe aim of this investigation was mainly to evaluate the multi-scale distribution of furfuryl alcohol (FA) resin in modified Chinese fir and poplar wood. 13C CP/MAS NMR, Scanning Electron Microscopy (SEM), Confocal Laser Scanning Microscopy (CLSM), Nanoindentation and Imaging Fourier transform infrared microscopy (Imaging FT-IR) were applied to describe the FA resin distribution in wood from bulk to cell wall scale. The results showed that FA resin were mainly located in the cell cavity of Chinese fir tracheids. For poplar, FA resin was mostly deposited in the cavity of fibers and ray cells, while little was found in the adjacent vessels. Lots of pits of wood cells were covered with FA resin which implied a higher risk of drying after wood furfurlation in practical production. Nanoindentation demonstrated that FA resin could easily infiltrate into the wood cell wall because both reduced modulus and hardness of the modified wood cell walls were significantly improved. This conclusion was further supported by the results of imaging FT-IR.
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5

Civiš, Svatopluk, Zdeněk Zelinger, Václav Nevrlý, Andrei Dorogan, Martin Ferus, Vladimir Iakovlev, Alexei Sirbu, et al. "Near-infrared wafer-fused vertical-cavity surface-emitting lasers for HF detection." Journal of Quantitative Spectroscopy and Radiative Transfer 147 (November 2014): 53–59. http://dx.doi.org/10.1016/j.jqsrt.2014.05.010.

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6

Jiang, Z. H., Z. Chen, B. H. Fen, Z. Q. Hou, and G. H. Chen. "Modeling Ovendry Softwood Resistivity Based on the Resistor Network Theory." Holzforschung 57, no. 4 (June 26, 2003): 415–20. http://dx.doi.org/10.1515/hf.2003.061.

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Анотація:
Summary This study develops a method to theoretically calculate ovendry softwood resistance and resistivity based on block transformation theory. The resistance of a single cell was calculated as the sum of a combination of serial and parallel connections of the two end cell walls, four side cell walls and cell cavity. One cell was considered as a resistor, and the wood as a network of single cell resistors. Resistance was calculated for a group of four resistors. After several iterations, the total resistance of wood was obtained. To test the model, experiments were conducted on Masson pine specimens. The resistances of fifty specimens were measured and their resistivities calculated. A comparison of the theoretical calculations and the measured results revealed a difference between the measured average resistivity of specimens and the model calculations of less than 8%. The resistivity of softwood was found to relate to the size of wood cells, amount of ray cells and the percentage of latewood.
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7

Demko, I. V., L. I. Pelinovskaya, A. Yu Kraposhina, V. E. Selin, A. E. Ryazanov, Ya I. Verigo, and V. A. Mosina. "Case of lifetime diagnosis of isolated primary amyloidosis of the heart." Kardiologiia 62, no. 1 (January 31, 2022): 106–8. http://dx.doi.org/10.18087/cardio.2022.1.n1049.

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Анотація:
The article presents a case of intravital diagnosis of a rare heart disease, isolated primary amyloidosis. The clinical onset of the disease was heart failure (HF) that was resistant to treatment; chemotherapy was ineffective and was poorly tolerated by the patient. The diagnostics was based on a combination of refractory HF and changes in echocardiography data (atrial dilatation, small size of the left ventricular cavity, interventricular septal hypertrophy with the presence of hyperechoic inclusions of the “granular fluorescence” type), and changes detected by contrast-enhanced cardiac magnetic resonance imaging. The diagnosis of amyloidosis was confirmed by results of pathohistological examination of the material obtained during autopsy.
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8

Journal, Baghdad Science. "Comparison of HF and HCl Chemical Laser Parameters by using Mathematical Model." Baghdad Science Journal 4, no. 1 (March 4, 2007): 119–24. http://dx.doi.org/10.21123/bsj.4.1.119-124.

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A simplified theoretical comparison of the hydrogen chloride (HCl) and hydrogen fluoride (HF) chemical lasers is presented by using computer program. The program is able to predict quantitative variations of the laser characteristics as a function of rotational and vibrational quantum number. Lasing is assumed to occur in a Fabry-Perot cavity on vibration-rotation transitions between two vibrational levels of hypothetical diatomic molecule. This study include a comprehensive parametric analysis that indicates that the large rotational constant of HF laser in comparison with HCl laser makes it relatively easy to satisfy the partial inversion criterion. The results of this computer program proved their credibility when compared with the little published data.
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9

Covasa, Mihai, Jeremy K. Marcuson, and Robert C. Ritter. "Diminished satiation in rats exposed to elevated levels of endogenous or exogenous cholecystokinin." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 280, no. 2 (February 1, 2001): R331—R337. http://dx.doi.org/10.1152/ajpregu.2001.280.2.r331.

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Анотація:
Rats maintained on a high-fat (HF) diet exhibit reduced sensitivity to the satiation-producing effect of exogenous CCK. Because more CCK is released in response to HF meals than low-fat (LF) meals, we hypothesized that increased circulating CCK associated with ingestion of HF diets contributes to the development of decreased CCK sensitivity. To test this hypothesis, we implanted osmotic minipumps filled with either NaCl or CCK octapeptide into the peritoneal cavity. Subsequently, we examined the effect of intraperitoneal NaCl or CCK (0.5 μg/kg) injection on 30-min food intake. CCK significantly reduced 30-min food intake less in rats implanted with CCK-releasing minipumps compared with those with NaCl-releasing minipumps. Because dietary protein is a potent releaser of endogenous CCK, we hypothesized that rats adapted to a high-protein (HP) diet might also exhibit reduced sensitivity to exogenous CCK. Therefore, in a second experiment, we examined CCK-induced reduction of food intake in rats maintained on LF and rats maintained on HF or HP. Ingestion of LF stimulates very little endogenous CCK secretion, whereas both HF and HP markedly increase plasma CCK concentrations. Both doses of CCK reduced food intake significantly less in HF and HP rats compared with LF rats. There were no differences in 24-h food intake, body weight, or body fat composition among LF-, HF-, and HP-fed rats. These results are consistent with the hypothesis that sustained elevation of CCK either by infusion of exogenous CCK or by dietary-induced elevation of plasma CCK contributes to the development of reduced sensitivity to exogenous CCK.
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10

Donaldson, Lloyd, Jamie Hague, and Rebecca Snell. "Lignin Distribution in Coppice Poplar, Linseed and Wheat Straw." Holzforschung 55, no. 4 (June 21, 2001): 379–85. http://dx.doi.org/10.1515/hf.2001.063.

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Summary Lignin distribution was determined by interference microscopy, and by confocal laser scanning microscopy (CLSM) for a range of agricultural residues including coppice poplar, linseed, and wheat straw. Interference microscopy was used to determine the lignin concentration in the middle lamella at the cell corner, and for the secondary wall of libriform fibres in the secondary xylem of poplar and linseed. Wheat was examined in the same way for cortical fibres. In addition the secondary wall of vessel elements was examined for poplar. Confocal microscopy was used to confirm the results from interference microscopy by providing semiquantitative information based on lignin autofluorescence, and by staining with acriflavine. Wheat had the lowest level of lignification, with 31 % lignin in the middle lamella of cortical fibres and 9% lignin in the secondary wall. Poplar had a lignin concentration of 63% in the middle lamella and 6% in the secondary wall of libriform fibres, while linseed had corresponding values of 69 % and 13 %. The secondary wall of poplar vessel elements had a lignin concentration of 25 %. In all three species most of the stem tissue was lignified except for phloem and bark, where present. In linseed the pith was unlignified. In wheat, most of the parenchyma cells were lignified except for a few cells lining the stem cavity. Libriform fibres in poplar and linseed sometimes had an unlignified gelatinous layer in samples containing tension wood. In linseed, lignification was greater in xylem fibres compared to bast fibres. Ray parenchyma cells of poplar and linseed appeared to be lignified to the same extent as xylem fibres.
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11

Larina, V. N., V. I. Lunev, and M. N. Alekhin. "Left ventricular global function index: prognostic value in patients with heart failure aged 60 years and older." Cardiovascular Therapy and Prevention 19, no. 5 (November 14, 2020): 2404. http://dx.doi.org/10.15829/1728-8800-2020-2404.

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Анотація:
Left ventricular (LV) global function index (LVGFI) is a novel marker that incorporates the functional and structural characteristics of the LV.Aim. To evaluate the prognostic value of LVGFI in outpatients with heart failure with preserved ejection fraction (HFpEF) aged 60 years and older.Material and methods. The study included 78 patients (male, 42%) aged 74 (67-77) years with NYHA class II-III heart failure. LVGFI was defined as LV stroke volume/LV global volume х 100, where LV global volume was the sum of the LV mean cavity volume ((LV end-diastolic volume + LV end-systolic volume)/2) and myocardial volume (LV mass/ density).Results. The median LVGFI was 21,7% (interquartile range 19,3 to 22,9%). Higher NYHA class of HF was associated with worse LVGFI:class II HF was associated with LVGFI of 22,0 (20,3-23,1)%, class III HF — with 20,4 (17,5-22,4)%. During the 3—month (24-48) follow-up period, 15 (19,2%) patients died. Among patients with NYHA class II HF, 6 out of 61 (9,8%) died, with class III HF — 9 out of 17 (53,0%) (p<0,001). According to ROC analysis, the optimal LVGFI cut-off point for the prediction of an unfavorable prognosis in patients with HFpEF aged 60 years was ≤21,1% (p<0,001). The sensitivity was 73,3%, specificity — 70,0%. Patients with LVGFI ≤21,1% had significantly lower survival: among patients with LVGFI ≤21,1%, 11 out of 30 (36,7%) died; among those with LVGFI >21,1%, 4 out of 48 (8,3 %) died (p=0,016).Conclusion. Higher NYHA class of HF was associated with worse LVGFI. Patients with lower LVGFI have significantly lower survival. The optimal LVGFI cut-off point for the prediction of an unfavorable prognosis in patients with HFrEF aged 60 years was <21,1%.
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12

Li, Hao, Yonghong Deng, Haisong Wu, Yuan Ren, Xueqing Qiu, Dafeng Zheng, and ChunLi Li. "Self-assembly of kraft lignin into nanospheres in dioxane-water mixtures." Holzforschung 70, no. 8 (August 1, 2016): 725–31. http://dx.doi.org/10.1515/hf-2015-0238.

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Abstract Kraft lignin (KL), a by-product in the pulping and papermaking industry, is an abundant, renewable resource. In this work, nanosphere formation of KL has been investigated via self-assembly induced by adding water to a KL/dioxane solution. The KL nanospheres were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (dynLS) and static light scattering (statLS). It was found that the nanoparticles have uniform nanospherical morphologies, including a small hollow cavity space in the interior. The π-π interactions between the aromatic rings of KL are demonstrated to be an important driving force in the self-assembly process. The KL nanosphere sizes can vary by hundreds of nanometers depending upon the preparation conditions. These newly obtained KL nanospheres have the advantages of biocompatibility, biodegradability, low toxicity, easy preparation, and low cost. Thus KL nanospheres are attractive for applications in life science, medicine, biology, food science, and agriculture. This approach presented here is an economically feasible and facile strategy for the sustainable utilization of kraft lignin.
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13

Bordes, Julien, Bertrand Jop, Sandrine Imbert, Sami Hraiech, Frédéric Collard, and François Kerbaul. "A Rare Cause of Heart Failure Treated by Heart Transplantation: Noncompaction of the Ventricular Myocardium." Case Reports in Medicine 2009 (2009): 1–3. http://dx.doi.org/10.1155/2009/725879.

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Анотація:
Noncompaction of the ventricular myocardium is a rare cardiomyopathy due to an arrest of myocardial morphogenesis. The characteristic echocardiographic findings are prominent myocardial trabeculations and deep intertrabecular spaces communicating with the left ventricular cavity. The clinical manifestations include heart failure (HF) signs, ventricular arrhythmias, and cardioembolic events. We describe an illustrative case of noncompaction of the ventricular myocardium associated with bicuspid aortic valve, a 42-year-old male presenting a refractory acute heart failure successfully treated by emergency heart transplantation.
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14

Novitskiy, Andrey A., Denis V. Chuprov, Vladislav A. Kuznetsov, and Eugeniy A. Shevtsov. "The features of the characteristic electromagnetic plasma bunches oscillations in the long magnetic mirror." Discrete and Continuous Models and Applied Computational Science 27, no. 4 (December 15, 2019): 355–64. http://dx.doi.org/10.22363/2658-4670-2019-27-4-355-364.

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Анотація:
The aim of this work was to study the spectrum of LF and HF oscillations generated by plasma bunches created and confined in the volume of a microwave cavity immersed in the magnetic field of a mirror trap. The registration of electrostatic oscillations in the plasma was carried out using two flat electrodes mounted diametrically opposite in the central part of the cavity close to its wall. This diagnostic showed the presence of low-frequency oscillations with frequencies of 130 kHz and 450 kHz. The oscillation spectrum in the microwave range was recorded at the minimum of the magnetic trap using a real-time spectrometer and a loosely coupled loop antenna. The registration of the spectra in the 40 MHz band revealed a regular change in the frequency of the fundamental oscillation mode of the cavity and the presence of two harmonics of the synchrotron radiation of the plasma bunch at frequencies of 2.25 GHz and 4.52 GHz, respectively. According to the obtained data, the parameters of the formed bunch (density, shape, volume, energy spectra of plasma components) can be restored.
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15

Komori, Kana, Jens Rip, Yukifumi Yoshida, Kurt Wostyn, Farid Sebaai, Wen Dar Liu, Yi Chia Lee, et al. "SiGe vs. Si Selective Wet Etching for Si Gate-all-Around." Solid State Phenomena 282 (August 2018): 107–12. http://dx.doi.org/10.4028/www.scientific.net/ssp.282.107.

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Анотація:
Gate All-Around (GAA) is considered a key design feature for future CMOS technology. SiGe vs. Si selective etch is required for Si nanowire formation in GAA. It is confirmed the selective SiGe removal with commodity chemical (mixtures of hydrofluoric acid (HF), hydrogen peroxide (H2O2) and acetic acid (CH3COOH, HAc)), however the thick oxidized layer on Si NW was observed after commodity chemical process, which is indicated the significant Si NW loss. On the other hand, the formulated mixture ACT® SG-101, which is focusing on SiGe oxidizer, chemical pH, solvent polarity & corrosion inhibitor for chemical concept, was performed higher selectivity and lower Si loss than commodity chemical. The formulated mixture has also been used to form an inner spacer for cavity etch scheme and confirmed uniform cavity etch and inner spacer filling on topological test structure.
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16

Shokair, T. M., J. Root, K. A. Van Bibber, B. Brubaker, Y. V. Gurevich, S. B. Cahn, S. K. Lamoreaux, et al. "Future directions in the microwave cavity search for dark matter axions." International Journal of Modern Physics A 29, no. 19 (July 30, 2014): 1443004. http://dx.doi.org/10.1142/s0217751x14430040.

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Анотація:
The axion is a light pseudoscalar particle which suppresses CP-violating effects in strong interactions and also happens to be an excellent dark matter candidate. Axions constituting the dark matter halo of our galaxy may be detected by their resonant conversion to photons in a microwave cavity permeated by a magnetic field. The current generation of the microwave cavity experiment has demonstrated sensitivity to plausible axion models, and upgrades in progress should achieve the sensitivity required for a definitive search, at least for low mass axions. However, a comprehensive strategy for scanning the entire mass range, from 1–1000 μeV, will require significant technological advances to maintain the needed sensitivity at higher frequencies. Such advances could include sub-quantum-limited amplifiers based on squeezed vacuum states, bolometers, and/or superconducting microwave cavities. The Axion Dark Matter eXperiment at High Frequencies (ADMX-HF) represents both a pathfinder for first data in the 20–100 μeV range (~5–25 GHz), and an innovation test-bed for these concepts.
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17

Nasseri, Lyes, Omar Rahli, Djamel Eddine Ameziani, and Rachid Bennacer. "Study of mixed convection in closed enclosure with a ceiling fan." European Physical Journal Applied Physics 86, no. 2 (May 2019): 20902. http://dx.doi.org/10.1051/epjap/2019190045.

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This paper presents a numerical study of heat transfer by convection in a square cavity. The vertical walls of the cavity are differentially heated and the horizontal ones are considered adiabatic. A fan is placed in the middle of the cavity and releases a jet down. Numerical simulation was performed using the lattice Boltzmann method to show the flow patterns and the heat flux depending on the Rayleigh number (thermal convection intensity) and the Reynolds number (fan-driven flow intensity). A parametric study was performed presenting the influence of Reynolds number (20 ≤ Re ≤ 500), Rayleigh number (10 ≤ Ra ≤ 106) and the fan position (0.2 ≤ HF ≤ 0.8). In forced convection mode, the flow structure has been mapped according to the position and the power of the fan. Three structures have emerged: two symmetrical cells, four symmetrical cells and asymmetrical structure. It has been observed that the heat transfer rate increases with the rise of Reynolds number and the reduction of the distance of the fan position from the ceiling. For the latter one, an unfavorable evolution of Nusselt number is observed for Ra > 104.
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18

Samson, J. C., R. A. Greenwald, J. M. Ruohoniemi, T. J. Hughes, and D. D. Wallis. "Magnetometer and radar observations of magnetohydrodynamic cavity modes in the Earth's magnetosphere." Canadian Journal of Physics 69, no. 8-9 (August 1, 1991): 929–37. http://dx.doi.org/10.1139/p91-147.

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Анотація:
Night and early morning data from the Johns Hopkins University, Applied Physics Laboratory HF radar at Goose Bay and from the magnetometers in the Canadian CANOPUS array often show structured spectra with distinct spectral peaks at 1.3, 1.9, and 2.6 mHz. These frequencies are very stable and vary by less than ±5% for the 6 days of data we have analysed. The radar measurements of the F-region drift velocities indicate that these spectral peaks are often associated with field line resonances of the shear Alfvén wave, and that the resonances are seen at lower latitudes as the frequency increases. The magnetometer data indicate that the magnetohydrodynamic (MHD) waves have westward phase velocities. We shall show that these observations are compatible with the formation of MHD cavity modes in the early morning and nightside magnetosphere, between the magnetopause, at approximately 14.5 RE, and turning points in the dipolar magnetosphere, outside the plasmasphere. Likely sources of energy are compressional pulses from the solar wind or Kelvin–Helmholtz instabilities in the low-latitude boundary layer.
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19

Savva, N. E. "О возможной природе сталактитоподобных образований в агатах Ольского плато (Северо-Восток России)". Bulletin of the North-East Science Center, № 1 (28 березня 2022): 31–39. http://dx.doi.org/10.34078/1814-0998-2022-1-31-39.

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Анотація:
The features of the stalactite-like formations relationship with onyxes in the geodes of the Ola basalt plateau agates are considered. It is shown that such formations are formed from the gel in the arc parts of cavities and flow down in the shape of icicles under the influence of gravity. "Stalactites" intersect previously formed layers of opal, chalcedony, quartz. The onyx layers. consisting of the silica group (SiO2,) minerals, can be dissolved only with the participation of F or HF. This is especially important in the case of poured basalts, since they contain no silica (SiO2) minerals, and silicon crystallizes in a different coordination (SiO4, Si3O8) in feldspars, olivine, etc. Geode filling with silica can be explained by the passage of gaseous HF and F from volcanic emanations through the thickness of silicon-containing rocks, with partial Si dissolution and formation of gaseous silicon tetrafluoride (SiF4), which fills cavities (bubbles) in basalt lavas. Subsequently, when meteoric water seeps into the cavity, silicon tetrafluoride is hydrolyzed to form orthosilicic acid, which is transformed into silica gel; the latter polymerizes to form chalcedony. Simultaneously, the remains of F either evaporate through cracks or accumulate in the cavity arch, again dissolving basalt in the vault of the geode (cycle repetition), with the formation of a viscous gel-like substance containing fluorine, which flows down in jets and polymerizes, thus creating stalactite-like structures. The author uses the photographs of agates found by B. M. Sedov in his numerous hikes to the Ola basalt plateau. The photographs were published in the wonderful book, "Agates from Upstream of the Ola River (Russia)" by B. M. Sedov.
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20

Eriksen, E., M. A. Golombeck, S. Junge, and O. Dössel. "SIMULATION OF A BIRDCAGE AND A CERAMIC CAVITY HF-RESONATOR FOR HIGH MAGNETIC FIELDS IN MAGNETIC RESONANCE IMAGING." Biomedizinische Technik/Biomedical Engineering 47, s1b (2002): 754–57. http://dx.doi.org/10.1515/bmte.2002.47.s1b.754.

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21

Wang, Pan, Xiang Ma, Le Kang, Cheng Zhang, and Hong Qiang Nian. "Effect of Different CaF2 Powder on Micromechanism and Dissolution Rates of CaF2 Block." Advanced Materials Research 1058 (November 2014): 118–21. http://dx.doi.org/10.4028/www.scientific.net/amr.1058.118.

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Анотація:
CaF2could be used as inner protection liner material of the cavity which is chemical etched by H2O and HF. This is because CaF2is not easy deliquescence, corrosion resistance and self-lubricating properties. This paper mainly analysis and research the three kinds of powder form different manufacture factory. The powder is burned in the air at 1360°C for 0.5h, the result display that the density of block we get after a powder is burned is the biggest and the width of the peak gets narrow after were calcined, which indicates the crystallinity has improved. The powder did not react with water at 90°C,but the powder was burned react with water at 90°C。
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22

Djemil, Rayenne, та Djameleddine Khatmi. "Theoretical study of inclusion complexes of dopamine with β-cyclodextrin based on PM6, ONIOM, and natural bonding orbital analysis". Canadian Journal of Chemistry 89, № 12 (грудень 2011): 1519–24. http://dx.doi.org/10.1139/v11-129.

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Анотація:
The inclusion process involving β-cyclodextrin (β-CD) with dopamine (DA) was investigated by using PM6, HF, and ONIOM methods. The most stable structure was obtained at the optimum position and angle. The complex orientation in which the catechol ring of dopamine penetrates into the β-CD cavity near primary hydroxyls is preferred in energy. The structures show the presence of several intermolecular hydrogen bond interactions that were studied on the basis of natural bonding orbital analysis, employed to quantify the donor–acceptor interactions between dopamine and β-CD. A study of these complexes in solution was carried out using the CPCM model to examine the influence of solvation on the stability of the dopamine β-CD complex.
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23

Sun Xu, 孙旭, 袁圣付 Yuan Shengfu, 罗威 Luo Wei, and 闫宝珠 Yan Baozhu. "Influence of Photon Absorption of Ground State Molecules in Resonator Cavity of HF-DF Dual-Band Chemical on Laser Output Performance." Chinese Journal of Lasers 40, no. 8 (2013): 0802004. http://dx.doi.org/10.3788/cjl201340.0802004.

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24

Rodrigues, Patricia G., Daniela Miranda-Silva, Sofia M. Costa, Carla Barros, Nazha Hamdani, Cláudia Moura, Maria J. Mendes, et al. "Early myocardial changes induced by doxorubicin in the nonfailing dilated ventricle." American Journal of Physiology-Heart and Circulatory Physiology 316, no. 3 (March 1, 2019): H459—H475. http://dx.doi.org/10.1152/ajpheart.00401.2018.

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Several studies have demonstrated that administration of doxorubicin (DOXO) results in cardiotoxicity, which eventually progresses to dilated cardiomyopathy. The present work aimed to evaluate the early myocardial changes of DOXO-induced cardiotoxicity. Male New Zealand White rabbits were injected intravenously with DOXO twice weekly for 8 wk [DOXO-induced heart failure (DOXO-HF)] or with an equivolumetric dose of saline (control). Echocardiographic evaluation was performed, and myocardial samples were collected to evaluate myocardial cellular and molecular modifications. The DOXO-HF group presented cardiac hypertrophy and higher left ventricular cavity diameters, showing a dilated phenotype but preserved ejection fraction. Concerning cardiomyocyte function, the DOXO-HF group presented a trend toward increased active tension without significant differences in passive tension. The myocardial GSSG-to-GSH ratio and interstitial fibrosis were increased and Bax-to- Bcl-2 ratio presented a trend toward an increase, suggesting the activation of apoptosis signaling pathways. The macromolecule titin shifted toward the more compliant isoform (N2BA), whereas the stiffer one (N2B) was shown to be hypophosphorylated. Differential protein analysis from the aggregate-enriched fraction through gel liquid chromatography-tandem mass spectrometry revealed an increase in the histidine-rich glycoprotein fragment in DOXO-HF animals. This work describes novel and early myocardial effects of DOXO-induced cardiotoxicity. Thus, tracking these changes appears to be of extreme relevance for the early detection of cardiac damage (as soon as ventricular dilation becomes evident) before irreversible cardiac function deterioration occurs (reduced ejection fraction). Moreover, it allows for the adjustment of the therapeutic approach and thus the prevention of cardiomyopathy progression. NEW & NOTEWORTHY Identification of early myocardial effects of doxorubicin in the heart is essential to hinder the development of cardiac complications and adjust the therapeutic approach. This study describes doxorubicin-induced cellular and molecular modifications before the onset of dilated cardiomyopathy. Myocardial samples from doxorubicin-treated rabbits showed a tendency for higher cardiomyocyte active tension, titin isoform shift from N2B to N2BA, hypophosphorylation of N2B, increased apoptotic genes, left ventricular interstitial fibrosis, and increased aggregation of histidine-rich glycoprotein.
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25

Provan, G., and T. K. Yeoman. "A comparison of field-line resonances observed at the Goose Bay and Wick radars." Annales Geophysicae 15, no. 2 (February 28, 1997): 231–35. http://dx.doi.org/10.1007/s00585-997-0231-y.

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Abstract. Previous observations with the Goose Bay HF coherent-scatter radar have revealed structured spectral peaks at ultra-low frequencies. The frequencies of these spectral peaks have been demonstrated to be extremely consistent from day to day. The stability of these spectral peaks can be seen as evidence for the existence of global magnetospheric cavity modes whose resonant frequencies are independent of latitude. Field-line resonances occur when successive harmonics of the eigenfrequency of the magnetospheric cavity or waveguide match either the first harmonic eigenfrequency of the geomagnetic field lines or higher harmonics of this frequency. Power spectra observed at the SABRE VHF coherent-scatter radar at Wick, Scotland, during night and early morning are revealed to show similarly clearly structured spectral peaks. These spectral peaks are the result of local field-line resonances due to Alfvén waves standing on magnetospheric field lines. A comparison of the spectra observed by the Goose Bay and Wick radars demonstrate that the frequencies of the field-line resonances are, on average, almost identical, despite the different latitudinal ranges covered by the two radars. Possible explanations for the similarity of the signatures on the two radar systems are discussed.
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26

Borges, Rodrigo, Marcus Vinícius Mariano Nascimento, Adryano Augustto Valladão de Carvalho, Marize Campos Valadares, José Realino de Paula, Elson Alves Costa, and Luiz Carlos da Cunha. "Antinociceptive and Anti-Inflammatory Activities of the Ethanolic Extract fromSynadenium umbellatumPax. (Euphorbiaceae) Leaves and Its Fractions." Evidence-Based Complementary and Alternative Medicine 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/715650.

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Synadenium umbellatumPax., popularly known in Brazil as “cola-nota,” “avelós,” “cancerola,” and “milagrosa”, is a plant species used in folk medicine for the treatment of inflammation, pain, and several diseases. This study aimed to investigate the antinociceptive and anti-inflammatory activities of the ethanolic extract fromSynadenium umbellatumPax. leaves (EES) and its hexane (HF), chloroform (CF), and methanol/water (MF) fractions using the acetic acid-induced abdominal writhing test, formalin-induced paw licking test, tail flick test, croton oil-induced ear edema test, and carrageenan-induced peritonitis test. EES and MF reduced the number of acetic acid-induced abdominal writhes, while CF and HF did not. EES effect on acetic acid-induced abdominal writhing was reversed with a pretreatment with naloxone. EES reduced licking time in both phases of the formalin-induced paw licking test, but did not prolong the latency in the tail flick test. These results show that EES presented antinociceptive activity, probably involving the opioid system, anti-inflammatory activity in the croton oil-induced ear edema test, and leukocyte migration into the intraperitoneal cavity. MF also presented anti-inflammatory activity in the croton oil-induced ear edema test. In conclusion, EES and MF have antinociceptive activity involving the opioid system and anti-inflammatory activity.
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27

Yeoman, T. K., D. M. Wright, T. R. Robinson, J. A. Davies, and M. Rietveld. "High spatial and temporal resolution observations of an impulse-driven field line resonance in radar backscatter artificially generated with the Tromsø heater." Annales Geophysicae 15, no. 6 (June 30, 1997): 634–44. http://dx.doi.org/10.1007/s00585-997-0634-9.

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Abstract. The CUTLASS Finland HF radar has been operated in conjunction with the EISCAT Tromsø RF ionospheric heater facility to examine a ULF wave characteristic of the development of a field line resonance (FLR) driven by a cavity mode caused by a magnetospheric impulse. When the heater is on, striating the ionosphere with field-aligned ionospheric electron density irregularities, a large enough radar target is generated to allow post-integration over only 1 second. When combined with 15 km range gates, this gives radar measurements of a naturally occurring ULF wave at a far better temporal and spatial resolution than has been achieved previously. The time-dependent signature of the ULF wave has been examined as it evolves from a large-scale cavity resonance, through a transient where the wave period was latitude-dependent and the oscillation had the characteristics of freely ringing field lines, and finally to a very narrow, small-scale local field line resonance. The resonance width of the FLR is only 60 km and this is compared with previous observations and theory. The FLR wave signature is strongly attenuated in the ground magnetometer data. The characterisation of the impulse driven FLR was only achieved very crudely with the ground magnetometer data and, in fact, an accurate determination of the properties of the cavity and field line resonant systems challenges the currently available limitations of ionospheric radar techniques. The combination of the latest ionospheric radars and facilities such as the Tromsø ionospheric heater can result in a powerful new tool for geophysical research.
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28

Azarov, M. A., Boris S. Aleksandrov, V. A. Drozdov, and G. A. Troshchinenko. "Influence of the cavity losses on the energy and spectral characteristics of a pulsed chemical chain-reaction HF (DF) laser." Quantum Electronics 30, no. 1 (January 31, 2000): 30–36. http://dx.doi.org/10.1070/qe2000v030n01abeh001652.

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29

Wu, Chen, Denesh Krishnasamy, and Janaka Elangage. "Hardware Implementation and RF High-Fidelity Modeling and Simulation of Compressive Sensing Based 2D Angle-of-Arrival Measurement System for 2–18 GHz Radar Electronic Support Measures." Sensors 21, no. 20 (October 14, 2021): 6823. http://dx.doi.org/10.3390/s21206823.

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This article presents the hardware implementation and a behavioral model-based RF system modeling and simulation (M&S) study of compressive sensing (CS) based 2D angle-of-arrival (AoA) measurement system for 2–18 GHz radar electronic support measures (RESM). A 6-channel ultra-wideband RF digital receiver was first developed using a PXIe-based multi-channel digital receiver paired with a 6-element random-spaced 2D cavity-backed-spiral-antenna array. Then the system was tested in an open lab environment. The measurement results showed that the system can measure AoA of impinging signals from 2–18 (GHz) with overall RMSE of estimation at 3.60, 2.74, 1.16, 0.67 and 0.56 (deg) in L, S, C, X and Ku bands, respectively. After that, using the RF high-fidelity M&S (RF HF-M&S) approach, a 6-channel AoA measurement system behavioral model was also developed and studied using a radar electronic warfare (REW) engagement scenario. The simulation result showed that the airborne AoA measurement system could successfully measure an S-band ground-based target acquisition radar signal in the dynamic REW environment. Using the RF HF-M&S model, the applicability of the system in other frequencies within 2–18 (GHz) was also studied. The simulation results demonstrated that the airborne AoA measurement system can be used for 2–18 GHz RESM applications.
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30

Kapustina, A. Yu, L. O. Minushkina, M. N. Alekhin, N. D. Selezneva, V. I. Safaryan, V. A. Brazhnik, O. S. Chumakova, et al. "Left ventricular global function index as a predictor of adverse cardiovascular events in patients with acute coronary syndrome." Kardiologiia 61, no. 8 (August 31, 2021): 23–31. http://dx.doi.org/10.18087/cardio.2021.8.n1508.

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Aim To evaluate the prognostic significance of the left ventricular global function index (LV GFI) in patients with acute coronary syndrome (ACS) using echocardiography (EchoCG).Material and methods The LV GFI is an index that integrates LV cavity volumes, stroke volume, and myocardial volume. This study included 2169 patients with ACS (1340 (61.8%) men) aged 64.1±12.6 years from two observational multicenter studies, ORACLE I and ORACLE II. 1800 (83 %) cases were associated with increased concentrations of myocardial injury markers, including 826 (38.1 %) cases of ST segment elevation myocardial infarction (MI). The observation was started on the 10th day of clinical condition stabilization and lasted for one year. EchoCG was performed with evaluation of LV GFI, which was calculated as a ratio of LV stroke volume to LV global volume. The LV global volume was calculated as a sum of mean LV cavity volume (LV end-diastolic volume + LV end-systolic volume / 2) and LV myocardial volume.Results The main outcome of the study was all-cause death (n=193); recurrent coronary complications (n=253) were analyzed separately. The only EchoCG parameter indicating an adverse outcome during the one-year follow-up was a LV GFI decrease to below 22.6 % with a sensitivity of 72 % and a specificity of 60% (area under the curve, AUC=0.63). A LV GFI <22.6 % was an independent predictor of all-cause death (p=0.019) along with age (p=0.0001), history of MI (p=0.034), and presence of heart failure (HF) (p=0.044), diabetes mellitus (p=0.012), and peripheral atherosclerosis (p=0.001). The LV GFI <22.6 %, (p=0.044), heart rate upon discharge from the hospital (p=0.050), history of MI (p=0.006), presence of HF (p=0.014), and peripheral atherosclerosis (p=0.001) were also independent predictors for recurrent coronary complications. Decreased LV GFI was associated with the risk of fatal outcomes independent of the LV ejection fraction at baseline.Conclusion In patients with ACS, the left ventricular global function index is an independent predictor for all-cause death and recurrent coronary complications and may be used for risk stratification.
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31

Ulmanová, Jana, and Zdeněk Dolníček. "Minerály pegmatitových hnízd z okolí Jablonce nad Nisou (krkonošsko-jizerský pluton) - část I. silikáty." Bulletin Mineralogie Petrologie 28, no. 2 (2020): 466–82. http://dx.doi.org/10.46861/bmp.28.466.

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We have studied silicate minerals in pegmatite nests from the Tanvald Granite (4 sites) and the Liberec Granite (1 site) in the vicinity of Jablonec n. Nisou, situated within the Variscan Krkonoše-Jizera Pluton. They contain major quartz, K-feldspar and plagioclase (An0-11), subordinate biotite, muscovite and locally schorl. Accessory phases include garnet (spessartine-almandine), andalusite, Hf-rich zircon and thorite. In addition, zinnwaldite was found in a single sample. The studied pegmatites show simple internal structure including aplitic, granitic and coarse-grained “blocky” units; the central zone commonly contains miarolitic cavity which is sometimes filled by tourmaline. The mineral composition and fractionation degree largely reflect those of the host granite; the more fractionated are pegmatites hosted by the Tanvald Granite. The pegmatite nest from Nová Ves nad Nisou II exhibits distinct mineral assemblage with zinnwaldite, pure albite and lack of biotite and garnet, therefore we suggest here a substantial modification of mineral assemblage by superimposed processes. Moreover, tourmaline (schorl) composition with local increasing of Mg toward rim indicates a possible contamination derived from adjacent rocks during tourmaline crystallization.
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32

Al-Kouz, Wael, Ahmad Al-Muhtady, Wahib Owhaib, Sameer Al-Dahidi, Montasir Hader, and Rama Abu-Alghanam. "Entropy Generation Optimization for Rarified Nanofluid Flows in a Square Cavity with Two Fins at the Hot Wall." Entropy 21, no. 2 (January 22, 2019): 103. http://dx.doi.org/10.3390/e21020103.

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Computational Fluid Dynamics (CFD) is utilized to study entropy generation for the rarefied steady state laminar 2-D flow of air-Al2O3 nanofluid in a square cavity equipped with two solid fins at the hot wall. Such flows are of great importance in industrial applications, such as the cooling of electronic equipment and nuclear reactors. In this current study, effects of the Knudsen number (Kn), Rayleigh number (Ra) and the nano solid particle’s volume fraction (ϕ) on entropy generation were investigated. The values of the parameters considered in this work were as follows: 0≤ Kn ≤0.1, 103 ≤Ra≤ 106, 0≤ ϕ ≤ 0.2. The length of the fins (LF) was considered to be fixed and equal to 0.5 m, whereas the location of the fins with respect to the lower wall (HF) was set to 0.25 and 0.75 m. Simulations demonstrated that there was an inverse direct effect of Kn on the entropy generation. Moreover, it was found that when Ra was less than 104, the entropy generation, due to the flow, increased as ϕ increases. In addition, the entropy generation due to the flow will decrease at Ra greater than 104 as ϕ increases. Moreover, the entropy generation due to heat will increase as both the ϕ and Ra increase. In addition, a correlation model of the total entropy generation as a function of all of the investigated parameters in this study was proposed. Finally, an optimization technique was adapted to find out the conditions at which the total entropy generation was minimized.
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33

Belyaev, A. A., A. P. Zhevlakov, V. G. Karel'skii, S. V. Konkin, Yurii P. Maksimov, Vitalii K. Rebone, S. B. Spiridonov, and Igor' A. Fedorov. "Investigation of the mirror characteristics and optimisation of the cavity of a supersonic cw chemical laser emitting the first overtone of the HF molecule." Quantum Electronics 26, no. 5 (May 31, 1996): 433–36. http://dx.doi.org/10.1070/qe1996v026n05abeh000690.

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34

Battancs, Emese, Márk Fráter, Tekla Sáry, Emese Gál, Gábor Braunitzer, Balázs Szabó P., and Sufyan Garoushi. "Fracture Behavior and Integrity of Different Direct Restorative Materials to Restore Noncarious Cervical Lesions." Polymers 13, no. 23 (November 29, 2021): 4170. http://dx.doi.org/10.3390/polym13234170.

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The purpose of this study was to analyze the fracture resistance and marginal leakage of noncarious cervical lesion (NCCL) restorations made of different restorative materials. Eighty upper premolars were randomly divided into four groups (n = 20/group). Standardized NCCL cavity preparations were performed on the buccal surface of the teeth and then restored with four different materials. Group 1: Packable resin composite (PC); Group 2: Highly flowable resin composite (HF); Group 3: Low flowable resin composite (LF); Group 4: Resin modified glass ionomer cement (RMGIC). After restorations were completed, cyclic and static fracture behavior was evaluated using a loading testing machine. Extra restored teeth were sectioned and then stained (n = 5/group). The specimens were viewed under a stereo microscope and the percentage of microgaps at the tooth–restoration interface was calculated. All restored teeth survived after fatigue loading. There was no statistically significant (p > 0.05) difference between the tested restorations after the static loading test. NCCLs restored with highly filled flowable composite showed the least microleakage among the tested groups (p < 0.05). The investigated restorative materials are acceptable for NCCL restorations in terms of fracture resistance and microleakage.
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35

McAllister, Michael A. "Characterization of low-barrier hydrogen bonds. 3. Hydrogen maleate. An ab initio and DFT investigation." Canadian Journal of Chemistry 75, no. 9 (September 1, 1997): 1195–202. http://dx.doi.org/10.1139/v97-144.

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Анотація:
High-level ab initio molecular orbital and density functional theory calculations predict the existence of a very short-strong hydrogen bond in the monoanion of maleic acid (hydrogen maleate). At all levels of theory (HF, MP2, BLYP, and B3LYP) except B3PW91 the potential energy surface is predicted to contain two minima, and hence resembles a double well. The barrier to proton transfer via a symmetrical transition state is calculated to be very small at all levels of theory. In all cases the calculated zero point vibrational energy available to the system is larger than the calculated barrier for proton transfer, thus the resulting hydrogen bond formed in hydrogen maleate is predicted to be symmetrical. Using the B3PW91 functional and the 6-31 + G(d,p) basis set results in a single-well potential and a symmetrically positioned hydrogen. All correlated methods predict the gas phase hydrogen bond energy to be approximately 27 kcal/mol. Effects due to solvents were estimated using solvent cavity methods. Approximating the solvent as a dielectric continuum reduces the calculated hydrogen bond energy by roughly 6 kcal/mol at all levels of theory. Keywords: low-barrier hydrogen bonds, short-strong hydrogen bonds, hydrogen maleate, ab initio, density functional theory.
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36

Nourredine Meddah Araibi, Nourredine Meddah Araibi, Teffaha Fergoug Teffaha Fergoug, Mansour Azayez Mansour Azayez, Cherifa Zelmat Cherifa Zelmat та Jendara Ali Cherif and Youcef Bouhadda Jendara Ali Cherif and Youcef Bouhadda. "Theoretical Study of the Complexation of Lidocaine by α- and β-Cyclodextrins". Journal of the chemical society of pakistan 43, № 4 (2021): 429. http://dx.doi.org/10.52568/000593/jcsp/43.04.2021.

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Structure and stability of an eventual inclusion complex formed by Lidocaine and two cyclodextrins (α- and β-CD) were investigated using molecular mechanics and quantum-chemical methods in the gas phase and in water. The molecular docking and quantum chemical calculations results show that no inclusion complex is formed between α-CD and Lidocaine molecule, while the conformational research allowed observing two minimum-energy structures between this molecule and β-CD. From a potential energy scan, a partial inclusion of the two ends of Lidocaine by the secondary face of the cavity of β-CD is observed with a better stability for the complex including the ((-N(C2H5)2) group in it. The minimum energy conformers, obtained by semi empirical method (PM3), have been exposed to fully geometry optimization employing ONIOM2 calculations by combining PM3 method with B3LYP, M06-HF and WB97XD functionals at 6-311G (d,p) basis set. The results show that complexation reactions are thermodynamically favored (Gand#176; ˂ 0) and the inclusion complexes are energetically stables and well structured (Sand#176; ˂ 0). According to the analysis of natural bond orbitals, the Van der Waals interactions are the sole driving forces that ensure the stability of the formed complexes.
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37

Nourredine Meddah Araibi, Nourredine Meddah Araibi, Teffaha Fergoug Teffaha Fergoug, Mansour Azayez Mansour Azayez, Cherifa Zelmat Cherifa Zelmat та Jendara Ali Cherif and Youcef Bouhadda Jendara Ali Cherif and Youcef Bouhadda. "Theoretical Study of the Complexation of Lidocaine by α- and β-Cyclodextrins". Journal of the chemical society of pakistan 43, № 4 (2021): 429. http://dx.doi.org/10.52568/000593.

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Анотація:
Structure and stability of an eventual inclusion complex formed by Lidocaine and two cyclodextrins (α- and β-CD) were investigated using molecular mechanics and quantum-chemical methods in the gas phase and in water. The molecular docking and quantum chemical calculations results show that no inclusion complex is formed between α-CD and Lidocaine molecule, while the conformational research allowed observing two minimum-energy structures between this molecule and β-CD. From a potential energy scan, a partial inclusion of the two ends of Lidocaine by the secondary face of the cavity of β-CD is observed with a better stability for the complex including the ((-N(C2H5)2) group in it. The minimum energy conformers, obtained by semi empirical method (PM3), have been exposed to fully geometry optimization employing ONIOM2 calculations by combining PM3 method with B3LYP, M06-HF and WB97XD functionals at 6-311G (d,p) basis set. The results show that complexation reactions are thermodynamically favored (Gand#176; ˂ 0) and the inclusion complexes are energetically stables and well structured (Sand#176; ˂ 0). According to the analysis of natural bond orbitals, the Van der Waals interactions are the sole driving forces that ensure the stability of the formed complexes.
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38

Draper, N. C., M. Lester, J. A. Wild, S. E. Milan, G. Provan, A. Grocott, S. W. H. Cowley, et al. "A joint Cluster and ground-based instruments study of two magnetospheric substorm events on 1 September 2002." Annales Geophysicae 22, no. 12 (December 22, 2004): 4217–28. http://dx.doi.org/10.5194/angeo-22-4217-2004.

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Abstract. We present a coordinated ground- and space-based multi-instrument study of two magnetospheric substorm events that occurred on 1 September 2002, during the interval from 18:00 UT to 24:00 UT. Data from the Cluster and Polar spacecraft are considered in combination with ground-based magnetometer and HF radar data. During the first substorm event the Cluster spacecraft, which were in the Northern Hemisphere lobe, are to the west of the main region affected by the expansion phase. Nevertheless, substorm signatures are seen by Cluster at 18:25 UT (just after the expansion phase onset as seen on the ground at 18:23 UT), despite the ~5 RE} distance of the spacecraft from the plasma sheet. The Cluster spacecraft then encounter an earthward-moving diamagnetic cavity at 19:10 UT, having just entered the plasma sheet boundary layer. The second substorm expansion phase is preceded by pseudobreakups at 22:40 and 22:56 UT, at which time thinning of the near-Earth, L=6.6, plasma sheet occurs. The expansion phase onset at 23:05 UT is seen simultaneously in the ground magnetic field, in the magnetotail and at Polar's near-Earth position. The response in the ionospheric flows occurs one minute later. The second substorm better fits the near-Earth neutral line model for substorm onset than the cross-field current instability model. Key words. Magnetospheric physics (Magnetosphereionosphere interactions; Magnetic reconnection; Auroral phenomenon)
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39

Aman, Khadija Shafiq, Mohammed Ahmed Alsaadi, and Mariam Taher Bin Yahiya. "Electrocardiographic and echocardiographic correlations of dilated cardiomyopathy in Aden Governorate." University of Aden Journal of Natural and Applied Sciences 24, no. 2 (March 22, 2022): 505–15. http://dx.doi.org/10.47372/uajnas.2020.n2.a18.

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Анотація:
Idiopathic dilated cardiomyopathy (IDCM), which represents ventricular chamber enlargement and contractile dysfunction is an often fatal cause of heart failure (HF) in young adults. In Yemen, the incidence and prevalence of dilated cardiomyopathy (DCM) appears to be increasing, whether secondary to improved detection or due to local factors, such as chronic khat use. In this prospective study, we sought to investigate the electrocardiographic and echocardiographic findings in patients with IDCM. A total of 50 patients with IDCM, from three hospitals in Aden were studied. The mean age of patients was 44.6 ±12 years, 39 were males and 11 were females. History of chronic khat use was found in 84% and family history of DCM was found in 32% of the patients. All secondary causes of DCM were excluded. Coronary artery disease (CAD) was excluded by coronary angiography. Electrocardiography (ECG) and two-dimensional (2D) echocardiography were done for all these patients using standard techniques. Diagnosis of DCM was one by echocardiography. Sinus tachycardia and ventricular ectopic beats were common ECG abnormalities, but atrial fibrillation, left bundle branch block, weak R wave progression in the chest leads were found to be associated with advanced left ventricular (LV) systolic dysfunction. There was a markedly dilated LV cavity with mean LV ejection fraction (EF) of 28%. While mitral regurgitation was seen in 40% of the patients, thrombus formation was found in 16% of patients with LVEF of <20%.
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40

Sbârcea, Laura, Ionuț-Mihai Tănase, Adriana Ledeți, Denisa Cîrcioban, Gabriela Vlase, Paul Barvinschi, Marinela Miclău, Renata-Maria Văruţ, Cristina Trandafirescu та Ionuț Ledeți. "Encapsulation of Risperidone by Methylated β-Cyclodextrins: Physicochemical and Molecular Modeling Studies". Molecules 25, № 23 (3 грудня 2020): 5694. http://dx.doi.org/10.3390/molecules25235694.

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Risperidone (RSP) is an atypical antipsychotic drug which acts as a potent antagonist of serotonin-2 (5TH2) and dopamine-2 (D2) receptors in the brain; it is used to treat schizophrenia, behavioral and psychological symptoms of dementia and irritability associated with autism. It is a poorly water soluble benzoxazole derivative with high lipophilicity. Supramolecular adducts between drug substance and two methylated β-cyclodextrins, namely heptakis(2,6-di-O-methyl)-β-cyclodextrin (DM-β-CD) and heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin (TM-β-CD) were obtained in order to enhance RSP solubility and improve its biopharmaceutical profile. The inclusion complexes were evaluated by means of thermoanalytical methods (TG—thermogravimetry/DTG—derivative thermogravimetry/HF—heat flow), powder X-ray diffractometry (PXRD), universal-attenuated total reflectance Fourier transform infrared (UATR-FTIR), UV spectroscopy and saturation solubility studies. Job’s method was employed for the determination of the stoichiometry of the inclusion complexes, which was found to be 2:1 for both guest–host systems. Molecular modeling studies were carried out for an in-depth characterization of the interaction between drug substance and cyclodextrins (CDs). The physicochemical properties of the supramolecular systems differ from those of RSP, demonstrating the inclusion complex formation between drug and CDs. The RSP solubility was enhanced as a result of drug encapsulation in the CDs cavity, the higher increase being obtained with DM-β-CD as host; the guest–host system RSP/DM-β-CD can thus be a starting point for further research in developing new formulations containing RSP, with enhanced bioavailability.
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41

Almatarneh, M. H., C. G. Flinn, and R. A. Poirier. "Ab initio study of the decomposition of formamidine." Canadian Journal of Chemistry 83, no. 12 (December 1, 2005): 2082–90. http://dx.doi.org/10.1139/v05-233.

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Анотація:
The decomposition of formamidine yielding hydrogen cyanide and ammonia has been investigated by ab initio calculations. Optimized geometries for reactants, transition states, and products were determined at the HF/6-31G(d) and MP2/6-31G(d) levels of theory. Energies were also determined at the G1, G2, G2MP2, G3, G3B3, G3MP2, and G3MP2B3 levels of theory. The role of water in the decomposition reaction of formamidine was examined. Intrinsic reaction coordinate (IRC) analysis was carried out for all transition states. Activation energies, enthalpies and free energies of activation were also calculated for each reaction pathway. G3 level of theory predicts the gas-phase decomposition of formamidine to have a high activation energy of 259.1 kJ mol–1. Adding one water molecule catalyses the reaction by forming a cyclic hydrogen-bonded transition state, reducing the barrier to 169.4 kJ mol–1 at the G3 level. Addition of a second water, which acts as a "solvent" molecule, further reduces the barrier to 151.1 kJ mol–1 at the G3 level. These values are still high and explain why rather extreme conditions are necessary to achieve this reaction experimentally. Thermodynamic properties (ΔE, ΔH, and ΔG) for each reaction pathway studied were also calculated. The G3 heats of reaction (ΔE) of the gas-phase decomposition of formamidine, its complex with one water molecule, and its complex with two water molecules are 0.9, 2.2, and –5.1 kJ mol –1, respectively. The G3 heat of reaction for the gas-phase decomposition to yield separated products is 22.3 kJ mol–1. Free energies of reaction and of activation in aqueous solution were calculated with PCM using the KLAMT cavity model. At MP2 the formamidine reaction is found to be exergonic in aqueous solution and to favour formation of the separated products (NH3 + HCN). The solvent model predicts a significant lowering of the free energy of activation (16–18 kJ mol–1) for the unimolecular reaction and 21–42 kJ mol–1 for the water-mediated reaction in aqueous solution relative to the gas phase. Key words: decomposition reaction, formamidine, Hartree–Fock, post Hartree–Fock, Gaussian-n theories, IRC, solvation models, PCM, KLAMT.
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42

Dzyurich, T. A., A. I. Chesnikova, V. P. Terentyev, O. E. Kolomatskaya, and V. A. Safronenko. "Evaluation of diagnostic criteria of heart failure in patients with atrial fibrillation and chronic obstructive pulmonary disease." Kardiologiia 59, no. 10S (December 23, 2019): 4–12. http://dx.doi.org/10.18087/cardio.n741.

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Aim. Assess the diagnostic significance of markers of heart failure, to identify the features of clinical symptoms and structural and functional remodeling of the left and right heart in patients with chronic heart failure (CHF) in combination with atrial fibrillation (AF) and chronic obstructive pulmonary disease (COPD). Materials and methods. groups of patients were formed: group 1 – patients with COPD without cardiovascular diseases (n=28), group 2 – patients with CHF and COPD without AF (n=30), group 3 – patients with CHF and AF without COPD (n=33), group 4 (main) – patients with CHF, AF and COPD (n=29). Patients were evaluated for clinical symptoms, 6-minute walk test, echocardiographic study, determined the concentration of natriuretic peptides (NUP): N-terminal fragment of the precursor of cerebral NUP (NT-proBNP) and mid-regional pro-atrial NUP (MR-proANP). Results. In patients with CHF on the background of AF and COPD, a higher score of the severity of clinical symptoms was established in comparison with the 3rd group (p<0,001). The features of heart remodeling in patients of the main group were revealed in comparison with patients with CHF and AF without COPD: lower volume indices of the left (p=0,001) and right (p=0,004) atria and values of the indexed index of the end-diastolic area of the right ventricle (RV) (p=0,007), lower contractility of the RV, the presence of RV hypertrophy. The effect of AF on the structural and functional parameters of the heart in patients with CHF, COPD and AF can be judged by comparison with patients with CHF and COPD without AF: higher values of the size of the RV (p=0,012), indexed index of the end-systolic area of the RV (p<0,001), lower systolic function of the RV on the background of higher pressure in the RV cavity (p=0,001). Defined the highest level of NT-proBNP in patients with CHF, AF and COPD in comparison with its level in patients of the 2nd group (p<0,001) and in patients 3rd groups (p=0,010). Higher levels of MR-proANP were found in patients with CHF and AF without COPD (p<0,001). Conclusion. In patients with CHF, AF and COPD, more pronounced clinical symptoms are caused by chronic bronchial obstruction. Pathogenetic features of left and right heart remodeling in patients with CHF on the background of AF and COPD were revealed. For the early detection of HF in patients with AF the greatest diagnostic importance is the determination of the level of MR-proANP, however, in patients with combined AF and COPD the most informative is the determination of the concentration of NT-proBNP.
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43

Klinov, D., A. Gulevich, V. Eliseev, I. Malysheva, and I. Buryevsky. "FEATURES OF THE CORE OF PERSPECTIVE FAST REACTORS." PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. SERIES: NUCLEAR AND REACTOR CONSTANTS 2020, no. 2 (June 26, 2020): 5–14. http://dx.doi.org/10.55176/2414-1038-2020-2-5-14.

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In the pre-Chernobyl period, the task of fast reactors was to provide fuel for the intensive development of nuclear energy with a deficit of natural uranium: short doubling time, high HF, high heat intensity, short campaign. After the Chernobyl accident, the main thing was to ensure safety, including in beyond design basis and postulated accidents. Modern fast sodium reactors must, on the one hand, satisfy the safety requirements in design and beyond design basis accidents (in accordance with the requirements of GEN-IV), and on the other, be competitive in comparison with water reactors and other energy sources. The article discusses the methods of transformation of the core of existing and planned Russian fast reactors to meet these requirements. The safety of these reactors in design and beyond design basis accidents is ensured by rejecting the upper end shield and replacing it with a sodium cavity, which allows reducing the NER and ensuring the input of negative reactivity when sodium boils. Such an core is implemented in BN-800 and the designed BN-1200. Improving the competitiveness (increasing the duration of the fuel campaign and KIUM) of the designed and existing reactors is ensured by switching to radiation-resistant clad steel EK164 (currently sold in BN-600, planned in BN-800) and the transition to the core with an axial layer of depleted uranium dioxide (planned for BN-800 and BN-1200). In BN-1200, due to the abandonment of a number of switchgear elements and optimization of the design, a one-and-a-half reduction in metal consumption is achieved. For fuel economy, a ″thick″ fuel rod with a diameter of 9.3 mm and a fuel campaign of 4 years have been adopted. This reduces the annual consumption of fuel rods and fuel assemblies by 2-2.5 times. Both events require modernization of the core. Each of these events allows you to increase the duration of the campaign by 25 %, and the implementation of both measures (transition to new steel and the introduction of a layer) will allow you to increase the campaign and reduce fuel consumption by more than 50 %. The introduction of the axial layer does not require core expansion, which gives additional fuel savings. But the axial layer should not be located in the central plane of the core, but with a shift of 3-5 cm downward. This will improve many characteristics of the core: increase fuel enrichment by a quarter and, as a result, proportionally reduce the neutron flux and radiation damage to the claddings of fuel elements; increase the fuel campaign to 5 years; to reduce the reactivity margin for burnout, without compromising the effectiveness of the control systems, to increase the micro-campaign to 1 year; to level the heat-release field in the vertical direction, to reduce the maximum heat intensity; to improve the course of beyond design basis accidents like ULOF. This method of reducing the rate of accumulation of a damaging dose is equally effective for both MOX and nitride fuels, which makes it possible to unify the core design.
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44

Patalakha, O. V. "The role of endogenous intoxication syndrome and the activity of the antioxidant protection system in the survival of generalized parodontitis in nuclear disease patients with toxic hepatitis." Clinical Dentistry, no. 4 (November 23, 2018): 19–30. http://dx.doi.org/10.11603/2311-9624.2018.4.9631.

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A prominent place in the structure of narcological disorders is opioid drug abuse. It has been detected that in patients with narcotic dependence, especially those who use substances based on opium, have the frequency and severity of oral cavity diseases significantly increased. Within patients with a different narcotic experience, predominantly, manifestations of generalized parodontitis (GP) are observed, with inflammatory-destructive processes in parodontum in drug addicts found in 2.5–10 times more frequent than in the population. The amplification of free radical oxidation of cell membranes with the accumulation of oxidation products is one of the essential links in the complex of mediators of inflammation in the periodontal disease. Intoxication, including narcotic drugs, results in insufficient antioxidant protection, which leads to the diffusion of products of free radical oxidation from soft tissues into bone with induction of collagen fibers destruction. Membrane-destructive processes with GP are insufficiently studied. The aim of the study – to learn the dynamics of indicators of antioxidant defense system in patients with generalized periodontitis with toxic hepatitis under opioid dependence, namely, the study of the level of middle molecules (MM) in serum and MTS, as well as the content of lipid peroxidation (LPO) and activity enzymes of the system of antioxidant protection (AOP) of drug addicted patients with toxic hepatitis at the aggravation of the inflammatory and destructive process in parodontium and comparison of these indices with the group of patients without drugs term dependence. Materials and Methods.122 patients with generalized periodontitis were examined. Of the 90 patients examined, they had a history of addiction and methadone replacement therapy. 32 patients with chronic generalized periodontitis of moderate severity did not use narcotic substances and formed a control group. Laboratory studies were conducted dynamically – before the course of preventive treatment and after its completion (after 20–24 days). Statistical processing of the results was performed using Microsoft Excel 2007 (Microsoft® Windows® XP Professional, USA) and Statistic v. 6.0 (StatSoft, USA). Calculated the basic statistical constants (M ± m). Results and Discussion. As the universal biochemical marker of the syndrome of endogenous intoxication (SEI), the most promising is the study of co-occurrence in blood and other biological fluids of metabolites – SM, with which the occurrence of secondary immunodeficiency (SID) is associated. We conducted a study of the level of SM in the blood serum and in the CSG, as well as the composition of LPO products and the activity of the enzymes of the AOZ system in drug-dependent patients with toxic hepatitis during exacerbation of the inflammatory-destructive process in the periodontium. The toxic properties of the molecules of the "average mass" in the exacerbation of the inflammatory-destructive process in the periodontium consist in their ability to participate in the development of SID, inhibit the phagocytic activity of leukocytes, induce neurotoxic effects and dramatically increase the permeability of capillary membranes, causing microcirculation disturbances. In patients with exacerbation of the inflammatory-destructive process in the periodontium (control group), the serum level of CM in the serum was doubled (at a rate of (0.52±0.05) g / L, P <0.001), which was (1.06±0.09) g / l. The concentration of SM in the blood serum of drug addicts with toxic hepatitis with exacerbation of HP is twice that of the control group SEI (P <0.001) and 4.17 times higher than the norm (P <0.001), which is (2.17±0.13) g / l. An analysis was made of the dynamics of growth of endogenous intoxication molecules of patients with toxic hepatitis with exacerbation of GP depending on the length of drug addiction. The content of SM in serum with a minimum "length of stay" averaged (1.51 ± 0.15) g / l, which is higher than the value in the control group at 1.39 times (P <0.001). In patients with a period of use of narcotic drugs from 2 to 4 years, the concentration of SM in the blood increased 2.21 times (P <0.001) and amounted to (2.34±0.28) g / l. The highest level of "average mass" molecules was observed in patients with "experience" of drug addiction for more than 4 years, which was (3.17±0.39) g / l, that is, a triple increase (P <0.001). The composition of CM in mixed saliva (non-invasive method) was also analyzed: in drug addicts, there was a more significant increase in SM in the salivary saliva of patients with toxic hepatitis in exacerbation of the inflammatory-destructive process in the periodontium. Thus, the SEI index exceeded the control value by 1.62 times and amounted to (0.55 ± 0.04) g / l (P <0.05), which characterizes the virulence of toxic autoaggression in the examined patients with opioid dependence and the insolvency of organs entering in the functional system of detoxification (liver, immune surveillance systems). The disturbance of lipid peroxidation processes in drug-dependent patients was analyzed depending on the duration of use of opioid preparations. The level of DC in patients with a short "experience" of drug dependence (up to 2 years) was 1.20 times higher than the control value (P <0.001), 1.41 times (P <0.001) over 2–4 years and more than 4 years – 1.59 times (P <0.001). The multiplicity of the increase in the final metabolites of lipid peroxidation also directly depended on the duration of drug dependence. Individual analysis with exacerbation of the inflammatory-destructive process in the periodontium showed multidirectional changes in the activity of enzymes of the AOZ system in the blood, depending on the presence or absence of addiction to narcotic substances. And so, in people with drug addiction against the background of intoxication with narcotic substances, stable changes in the activity of the AOZ system have been revealed: they become stronger with time. Thus, the activity of GP, SOD and CT in whole blood was significantly reduced with an increase in the length of drug dependence in all study groups. Weakness of antioxidant protection is one of the reasons for the progression of the inflammatory process in the periodontium, which gives grounds for the appointment as methods of metabolic correction of drugs with antioxidant activity. Conclusions. 1. The conducted study showed the presence of metabolic disorders in the exacerbation of the inflammatory and destructive process in periodontia in patients with toxic hepatitis opioid genesis, manifested by the syndrome of endogenous intoxication, characterized by an increase in the concentration of CM in serum and mixed saliva. In drug addicts with HF and toxic hepatitis there is a significant increase in the processes of lipid oxidation - an increase in the content of primary and secondary products (DK and MDA) in serum. At the same time, the most pronounced changes in the indicators of endogenous intoxication syndrome and LPA appeared in patients with a long history of narcotic addiction. Chronic intoxication with narcotic substances in patients with inflammatory-destructive process in periodontia is accompanied by an enzyme imbalance of the AOP system - inhibition of the activity of catalase, superoxide dismutase and glutathione peroxidase. The decrease in AOP activity indicates a deep imbalance in the system of free radical oxidation - antioxidant protection in the direction of activation of the LPO. The accumulation in the body of the products of the LPO (end – MDA and intermediate – DC) and the development of endotoxicosis, leads to stimulation of the monooxygenase system, changes in the reaction of lipid, hormonal, immune status, with the depletion of the antioxidant system. Activation of LPO promotes damage to cellular and subcellular biomembranes of hepatocytes and, accordingly, to the progression of the chronic pathological process in the liver parenchyma. The given data on the participation of free radical oxidation in the genesis of GP indicate the expediency of the use of antioxidants and other bioregulators in the complex therapy of patients with opioid dependence and toxic hepatitis.
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45

Souza, Elaine Roberta Leite de, José Henrique de Araújo Cruz, Nílvia Maria Lima Gomes, Júlia Tavares Palmeira, Heloisa Mara Batista Fernandes de Oliveira, Gymenna Maria Tenório Guênes, Maria Angélica Sátyro Gomes Alves, and Abrahão Alves de Oliveira Filho. "Fisiopatologia da pneumonia nosocomial: uma breve revisão." ARCHIVES OF HEALTH INVESTIGATION 9, no. 5 (April 20, 2020): 485–92. http://dx.doi.org/10.21270/archi.v9i5.4728.

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Introdução: A pneumonia nosocomial é definida como infecção do parênquima pulmonar que ocorre depois de aproximadamente 48 horas de internação e os principais microrganismos envolvidos nessa infecção são bastonetes Gram-negativos, é a complicação mais comum que ocorre entre os pacientes internados em UTIs, e os microrganismos que podem gerar essas infecções respiratórias estão predispostos à colonizar do biofilme bucal. Objetivo: Realizar uma revisão de literatura acerca da Pneumonia Nosocomial relacionada à odontologia, a fim de compreender fatores como aspectos gerais, tipos de bactérias mais frequentes, fisiopatologia, epidemiologia e o tratamento. Metodologia: As buscas foram realizadas no período de 10 de Janeiro a 10 de Maio de 2019, foram utilizados artigos científicos retirados das bases de dados: SCIELO, MEDLINE, LILACS, e monografias que atendiam aos requisitos. Os artigos utilizados como referências bibliográficas foram do período entre 2008 a 2018, com exceção de artigos clássicos. A pesquisa foi realizada tanto na língua portuguesa, como em inglês e espanhol. Foram utilizados como descritores para a busca: "Pneumonia Nosocomial", "Pneumoia Hospitalar”, “Pneumonia Hospitalar e Odontologia”, “Odontologia Hospitalar”, “Pneumonia associada à ventilação mecânica”,e com um resultado de 43 artigos utilizados. Conclusão: Portanto, a Pneumonia nosocomial pode ter relação com a cavidade bucal, deste modo é necessário a implantação do cirurgião dentista no âmbito hospitalar e na Unidade Terapia Intensiva (UTI) para o melhor controle dos microrganismos que colonizam a boca na forma de biofilme bucal e que se proliferam rapidamente quando não é feita higiene adequada e/ou fazem uso de medicações que geram hipossalivação. Descritores: Pneumonia Nosocomial; Unidade Terapia Intensiva; Odontologia. Referências Batista SA, Silva Junior A, Ferreira MF, Agostini M, Torres SR. Alterações orais em pacientes internados em unidades de terapia intensiva. Rev Bras Odontol. 2015;71(2):156-59. Padovani MCRL, Souza SAB, Santanna GR, Guaré RO. Protocolo de cuidados bucais na unidade de tratamento intensivo (UTI) neonatal. Rev Bras Pesq Saúde.2012;14(1):71-80. Gandolfo MC, Pessole T, Mendes G, Albara MF, Fontana A, Freisleben EV et al. Uso dos colutórios em Odontologia. Ação Odonto.2017;2:21. Muniz KGG. Atividade antimicrobiana in vitro de enxaguatórios bucais sobre bactérias do biofilme dentário [Mmonografia]. Campina Grande: Centro de Ciências Biológicas e da Saúde - Universidade Estadual da Paraíba; 2014. Andrade DP, Pallos D, Forte LFBP, Ricardo LH. A doxiciclina como adjuvante no tratamento da periodontite. IJD. Int J Dent. 2009;8(4):202-10. Morais TMN, Silva A, Avi ALRO, Souza PHR, Knobel E, Camargo LFH. A importância da atuação odontológica em pacientes internados em unidade de terapia intensiva. Rev Bras Ter Intensiva. 2010; 18(4):412-17. Soh KL, Shariff Ghazali S, Soh KG, Abdul Raman R, Sharif Abdullah SS, Ong SL. Oral care practice for the ventilated patients in intensive care units: a pilot survey. J Infect Dev Ctries. 2012;6(4):333-39. ANVISA − Agência Nacional de Vigilância Sanitária. Ministério da Saúde. Pediatria: Prevenção e controle de infecção hospitalar/ Ministério da Saúde, Agência Nacional de Vigilância Sanitária. – Brasília: Ministério da Saúde, 2011. Oliveira LCBS, Carneiro PPM, Fischer RG, Tinoco BEM. A presença de patógenos respiratórios no biofilme bucal de pacientes com pneumonia nosocomial. Rev bras ter intensiva. 2010;19(4):428-33. Bernardo WM, Nobre MRC, Jatene FB. A prática clinica baseada em evidências. Parte II: buscando as evidências em fontes de informação. Rev Assoc Med Bras. 2004;50(1):104-8. Sachdev M, Ready D, Brealey D, Ryu J, Bercades G, Nagle J, Borja-Boluda S, Agudo E, Petrie A, Suvan J, Donos N, Singer M, Needleman I. Changes in dental plaque following hospitalisation in a critical care unit: an observational study. Crit Care. 2013;17(5):R189. Dewhirst FE, Chen T, Izard J, Paster BJ, Tanner AC, Yu WH, Lakshmanan A, Wade WG. The human oral microbiome. J Bacteriol. 2010; 192(19):5002-17. Palmer RJ Jr. Composition and development of oral bacterial communities. Periodontol 2000. 2014;64(1):20-39. Pina-Vaz I, Barros J, Noites R, Villa-Vigil A, Pintado M, Carvalho MF. Estratégias anti-microbianas na prevenção e tratamento da infecção oral. Universidade Católica Portuguesa. Ciências da Saúde. 2011;14(55):1-12. Culler HF, Mota CM, Abe CM, Elias WP, Sircili MP, Franzolin MR. Atypical enteropathogenic Escherichia coli strains form biofilm on abiotic surfaces regardless of their adherence pattern on cultured epithelial cells. Biomed Res Int. 2014;2014:845147. Silva ACB, Cruz JS, Sampaio FC, Araújo DAM. Detecção de estreptococos orais em biofilme dental de crianças cárie-ativas e livres de cárie. Braz J Microbiol. 2008;39(4):648-51. Romeiro RL, Majewski M, Molina F, Junqueira JC, Oliveira L, Jorge AOC. Aderência de C. albicans, C. dubliniensis e C. glabrata à superfície de implantes lisos e rugosos. ImplantNews, 2009;6(1):33-37. Cruz MK, Morais TMN, Trevisani DM. Clinical assessment of the oral cavity of patients hospitalized in an intensive care unit of an emergency hospital. Rev bras ter intensiva. 2014;26(4):379-83. Bellissimo-Rodrigues F, Bellissimo-Rodrigues WT, Viana JM, Teixeira GC, Nicolini E, Auxiliadora-Martins M et al. Effectiveness of oral rinse with chlorhexidine in preventing nosocomial respiratory tract infections among intensive care unit patients. Infect Control Hosp Epidemiol. 2009;30(10):952-8. Alotaibi AK, Alshayiqi M, Ramalingam S. Does the presence of oral care guidelines affect oral care delivery by intensive care unit nurses? A survey of Saudi intensive care unit nurses. Am J Infect Control. 2014;42(8):921-22. Oliveira AC, Kovner CT, Silva RS. Infecção hospitalar em unidade de tratamento intensivo de um hospital universitário brasileiro Rev Latinoam Enfermagem. 2010;18(2):97-104. Figueiredo DA, Vianna RPT, Nascimento JA. Epidemiologia da infecção hospitalar em uma unidade de terapia intensiva de um hospital público municipal de João Pessoa-PB. Rev Bras Ciênc Saúde. 2013;17:233-40. Ribas RM, Gontijo Filho PP, Cezário RC, Silva PF, Langoni DRP, Duque AS. Fatores de risco para colonização por bactérias hospitalares multiresistentes em pacientes críticos, cirúrgicos e clínicos em um hospital universitário brasileiro. Rev Med Minas Gerais. 2009;19:193-7. Douglas IS, Price CS, Overdier KH, Wolken RF, Metzger SW, Hance KR, Howson DC. Rapid automated microscopy for microbiological surveillance of ventilator-associated pneumonia. Am J Respir Crit Care Med. 2015;191(5):566-73. Moreira BSG, Silva RMO, Esquivel DN, Fernandes JD. Pneumonia associada à ventilação mecânica: medidas preventivas conhecidas pelo enfermeiro. Rev Baiana Enferm.2011;25:99-106. Rodrigues PMA, Carmo NE, Santos LRC, Knibel MF. Pneumonia associada à ventilação mecânica: epidemiologia e impacto na evolução clínica de pacientes em uma unidade de terapia intensiva. J bras pneumol. 2009;35(11):1084-91. Palomar MÁLF, Olaechea P, López Pueyo MJ, Gimeno R, Gracia Arnillas MP, et al. Estudio nacional de vigilancia de infección nosocomial en servicios de medicina intensiva. Sociedad Española de Medicina Intensiva Crítica y Unidades Coronarias (SEMICYUC) Grupo de trabajo de enfermedades infecciosas y sepsis. 2015. Klepser ME. Aerosolized antibiotics for the treatment of nosocomial pneumonia. Medscape Medical News. 2012. Vardakas KZ, Matthaiou DK, Falagas ME. Incidence, characteristics and outcomes of patients with severe community acquired-MRSA pneumonia. Eur Respir J. 2009;34(5):1148-58. Écila CM, Silvânia PO, Beatriz RMS, Patrick LNS, Adriana CO. Incidência da pneumonia associada à ventilação mecânica em unidade de terapia intensiva. Medicina (Ribeirão Preto, Online), 2017;50(1):39-46. Souza AS. Prevalência de pneumonia associada à assistência à saúde em unidades de terapia intensiva [dissertação]. Campo Grande: Universidade Federal de Mato Grosso de Sul; 2012. Favarin SS, Camponogara S. Perfil dos pacientes internados na unidade de terapia intensiva adulto de um hospital universitário. Rev Enferm UFSM. 2012; 2:320-9. Souza AF, Guimarães AC, Ferreira EF. Avaliação da implementação de novo protocolo de higiene bucal em um centro de terapia intensiva para prevenção de pneumonia associada à ventilação mecânica. REME Rev Min Enferm. 2013;17:177-84. Amaral SM, Cortês Ade Q, Pires FR. Nosocomial pneumonia: importance of the oral environment. J Bras Pneumol. 2009;35(11):1116-24. Munro CL, Grap MJ, Jones DJ, McClish DK, Sessler CN. Chlorhexidine, toothbrushing, and preventing ventilator-associated pneumonia in critically ill adults. Am J Crit Care. 2009;18(5):428-37. Scannapieco FA, Yu J, Raghavendran K, Vacanti A, Owens SI, Wood K, Mylotte JM. A randomized trial of chlorhexidine gluconate on oral bacterial pathogens in mechanically ventilated patients. Crit Care. 2009;13(4):R117. Lorente L, Lecuona M, Jiménez A, Palmero S, Pastor E, Lafuente N, Ramos MJ, Mora ML, Sierra A. Ventilator-associated pneumonia with or without toothbrushing: a randomized controlled trial. Eur J Clin Microbiol Infect Dis. 2012;31(10):2621-29. Özçaka Ö, Başoğlu OK, Buduneli N, Taşbakan MS, Bacakoğlu F, Kinane DF. Chlorhexidine decreases the risk of ventilator-associated pneumonia in intensive care unit patients: a randomized clinical trial. J Periodontal Res. 2012;47(5):584-92. Bezerra EL, Lima AIF, Nóbrega ARR, Barroso DN, Donadi HA, Santos JGS et al. Prevalência de pneumonia em pacientes de uma unidade de terapia intensiva de um hospital- escola de fortaleza – CE. Rev Bras Promoç Saúde. 2012;25(2):20-4. Rosenthal VD, Rodrigues C, Álvarez-Moreno C, Madani N, Mitrev Z, Ye G et al. Effectiveness of a multidimensional approach for prevention of ventilator-associated pneumonia in adult intensive care units from 14 developing countries of four continents: findings of the International Nosocomial Infection Control Consortium. Crit Care Med. 2012;40(12):3121-28. Resende MM, Monteiro SG, Callegari B, Figueiredo PM, Monteiro CR, Monteiro-Neto V. Epidemiology and outcomes of ventilator-associated pneumonia in northern Brazil: an analytical descriptive prospective cohort study. BMC Infect Dis. 2013;13:119.
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46

Schubert, Sandy, Daniel Gsell, Jurg Dual, Masoud Motavalli, and Peter Niemz. "Acoustic wood tomography on trees and the challenge of wood heterogeneity." Holzforschung 63, no. 1 (January 1, 2009). http://dx.doi.org/10.1515/hf.2009.028.

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Abstract The assessment of tree stability requires information about the location and the geometry of fungal decay or of a cavity in the interior of the trunk. This work aims at specifying which size of decay or cavity can be detected non-destructively by acoustic wood tomography. In the present work, the elastic waves that propagate in a trunk during a tomographic measurement were visualized by numerical simulations. The numerical model enabled to systematically investigate the influence of fungal decay on tomographic measurements neglecting the heterogeneity of wood. The influence of wood heterogeneity was studied in laboratory experiments on trunks. The experiments indicated that the waveforms of the measured signals are by far more sensitive to the natural heterogeneity of trunk wood than the travel times, thereby making waveforms unsuitable for decay detection. Thus, it is recommended to further develop the travel time inversion algorithms for trunks and to neglect the information in waveforms or amplitudes. Fungal decay is detectable if the influence of the decay is distinguishable from the influence of the heterogeneity. It was found from the numerical analysis that the cross-section of a cavity, which is larger than 5% of the total cross-section of the trunk, can be detected by acoustic wood tomography.
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47

Schneibel, J. H., and L. Martinez. "Creep Cavitation in a Nickel Aluminide." MRS Proceedings 81 (1986). http://dx.doi.org/10.1557/proc-81-297.

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Анотація:
AbstractA nickel aluminide with the composition Ni-23.5 Al-O.5 Hf-O.2 B (at. %) was creep-tested in tension at constant load (initial stress 250 MPa, temperature 1033 K). The creep rate reaches a minimum at a strain of approximately 0.3%. Its increase at larger strains is partly caused by grain boundary cavitation. Cavity size distributions corresponding to different creep times and strains were determined metallographically and evaluated in order to obtain the cavity growth rate as a function of cavity size. Contrary to a newly developed model for crack-like diffusive growth the cavity tip velocity increases with cavity size. This discrepancy is attributed to cavity coalescence. Sintering at elevated temperatures (1473 K) reduces the diameter and increases the thickness of the disc-shaped cavities. Sintering of such cavities might be exploited to measure surface diffusivities.
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48

Au-Yeung, Patrick H., John T. Lukowski, and Calvin L. White. "Grain Boundary and Cavity Surface Segregation in Crept Ni3Al + 0.2at% B AND Ni3 (AI,Hf) + 0.2at% B." MRS Proceedings 133 (1988). http://dx.doi.org/10.1557/proc-133-517.

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Анотація:
ABSTRACTCreep strengths and ductilities of boron-doped nickel aluminides are significantly improved by small additions of hafnium. Since creep failure in these alloys proceeds by growth and coalescence of grain boundary cavities, effects of Hf additions on the compositions of grain boundaries and creep cavity surfaces were examined using Auger electron spectroscopy (AES). In order to facilitate intergranular fracture in the AES analysis chamber, gage sections from creep specimens were hydrogen charged and copper plated. Grain boundaries in crept specimens were not flat, and the grains did not exhibit a normal polyhedral appearance. The overall levels of boron detected on the fracture surfaces of the creep specimens were significantly higher than those from uncrept specimens. Additionally, boron was found to segregate more strongly to the grain boundaries while higher concentrations of residual sulfur and phosphorus were detected on the cavity surfaces in both alloys. These results are discussed in terms of the effects of impurity segregation on high temperature grain boundary cavitation.
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49

Jang, Eun-Suk, and Chun-Won Kang. "Sound absorption characteristics of three species (binuang, balsa and paulownia) of low density hardwood." Holzforschung, August 5, 2021. http://dx.doi.org/10.1515/hf-2021-0049.

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Анотація:
Abstract In this study, the sound absorption coefficient of three low density hardwoods – binuang, balsa and paulownia – were investigated. Their gas permeability and pore size were measured, and their pore shapes were classified into through pore, blind pored, and closed pore, as specified by the International Union of Pure and Applied Chemistry (IUPAC). Among the three species, obvious that paulownia had lowest sound absorption when the two of others showed higher sound absorption. Although paulownia is a high porosity wood, most of its vessels are blocked by tyloses; it is therefore difficult for sound waves to enter its pores, which results in poor sound absorption performance. This study showed that the higher the through pore porosity, the higher was the gas permeability, which led to improvement of the sound absorption performance. It was also found that the sound absorption coefficient of the three species woods increased at low frequencies as the size of an air cavity between the specimens and tube’s wall increased.
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50

Skyba, Oleksandr, Peter Niemz, and Francis W. M. R. Schwarze. "Degradation of thermo-hygro-mechanically (THM)-densified wood by soft-rot fungi." Holzforschung 62, no. 3 (May 1, 2008). http://dx.doi.org/10.1515/hf.2008.029.

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Анотація:
Abstract Thermo-hygro-mechanical (THM)-densified wood is more resistant to colonisation and degradation by brown-rot fungi than untreated wood. Colonisation and degradation by soft-rot fungi was investigated in treated Norway spruce (Picea abies) and treated beech (Fagus sylvatica) to assess their suitability for utility class 4. Three different treatments were applied: thermal-hygro (TH) treatment, mechanical densification and THM-treatment including densification and post-treatment under saturated steam conditions at different temperatures. For comparison, additional wood specimens were treated with two concentrations of a chromium-copper (CC) wood preservative. After 32 weeks incubation, weight losses induced by soft-rot fungi were lowest in wood treated with CC. Highest weight losses were recorded from TH-treated wood, in which soft-rot erosion attack (type 2) was exclusively observed in spruce. In comparison to controls, significantly lower weight losses by soft-rot fungi were recorded in THM-treated spruce wood, but no such differences were found in beech wood. Microscopical examination showed that in THM-treated wood of spruce, soft-rot type 1 commenced from the outer wood surfaces and cavity formation was not found in deeper regions of the wood samples. THM-treated beech wood was more susceptible to degradation than that of spruce which can be partly explained by the higher syringyl lignin content in beech wood, which is more susceptible to all kinds of degradation. Hyphal colonisation and soft-rot was facilitated within deeper regions of beech wood mainly in the non-occluded lumina of parenchyma cells in multiseriate xylem rays. It can be concluded that TH-treated spruce wood and THM-treated beech wood is susceptible to soft-rot and therefore inappropriate for utility class 4.
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