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31.
Dmitrii Shuleiko Stanislav Zabotnov Mikhail Martyshov Dmitrii Amasev Denis Presnov Vyacheslav Nesterov Leonid Golovan Pavel Kashkarov 《Materials》2022,15(21)
Femtosecond laser-modified amorphous silicon (a-Si) films with optical and electrical anisotropy have perspective polarization-sensitive applications in optics, photovoltaics, and sensors. We demonstrate the formation of one-dimensional femtosecond laser-induced periodic surface structures (LIPSS) on the surface of phosphorus- (n-a-Si) and boron-doped (p-a-Si) amorphous silicon films. The LIPSS are orthogonal to the laser polarization, and their period decreases from 1.1 ± 0.1 µm to 0.84 ± 0.07 µm for p-a-Si and from 1.06 ± 0.03 to 0.98 ± 0.01 for n-a-Si when the number of laser pulses per unit area increases from 30 to 120. Raman spectra analysis indicates nonuniform nanocrystallization of the irradiated films, with the nanocrystalline Si phase volume fraction decreasing with depth from ~80 to ~40% for p-a-Si and from ~20 to ~10% for n-a-Si. LIPSS’ depolarizing effect, excessive ablation of the film between LIPSS ridges, as well as anisotropic crystalline phase distribution within the film lead to the emergence of conductivity anisotropy of up to 1 order for irradiated films. Current–voltage characteristic nonlinearity observed for modified p-a-Si samples may be associated with the presence of both the crystalline and amorphous phases, resulting in the formation of potential barriers for the in-plane carrier transport and Schottky barriers at the electric contacts. 相似文献
32.
Tjede Funk Francesco Innocenti Joana Gomes Dias Lina Nerlander Tanya Melillo Charmaine Gauci Jackie M Melillo Patrik Lenz Helena Sebestova Pavel Slezak Iva Vlckova Jacob Dag Berild Camilla Mauroy Elina Seppl Ragnhild Tnnessen Anne Vergison Joël Mossong Silvana Masi Laetitia Huiart Gillian Cullen Niamh Murphy Lois OConnor Joan ODonnell Piers Mook Richard G Pebody Nick Bundle 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(35)
BackgroundUnderlying conditions are risk factors for severe COVID-19 outcomes but evidence is limited about how risks differ with age.AimWe sought to estimate age-specific associations between underlying conditions and hospitalisation, death and in-hospital death among COVID-19 cases.MethodsWe analysed case-based COVID-19 data submitted to The European Surveillance System between 2 June and 13 December 2020 by nine European countries. Eleven underlying conditions among cases with only one condition and the number of underlying conditions among multimorbid cases were used as exposures. Adjusted odds ratios (aOR) were estimated using 39 different age-adjusted and age-interaction multivariable logistic regression models, with marginal means from the latter used to estimate probabilities of severe outcome for each condition–age group combination.ResultsCancer, cardiac disorder, diabetes, immunodeficiency, kidney, liver and lung disease, neurological disorders and obesity were associated with elevated risk (aOR: 1.5–5.6) of hospitalisation and death, after controlling for age, sex, reporting period and country. As age increased, age-specific aOR were lower and predicted probabilities higher. However, for some conditions, predicted probabilities were at least as high in younger individuals with the condition as in older cases without it. In multimorbid patients, the aOR for severe disease increased with number of conditions for all outcomes and in all age groups.ConclusionWhile supporting age-based vaccine roll-out, our findings could inform a more nuanced, age- and condition-specific approach to vaccine prioritisation. This is relevant as countries consider vaccination of younger people, boosters and dosing intervals in response to vaccine escape variants. 相似文献
33.
Capó-Aponte JE Wang Z Bildin VN Iserovich P Pan Z Zhang F Pokorny KS Reinach PS 《Experimental eye research》2007,84(6):1090-1103
The dependence of regulatory volume decrease (RVD) activity on potassium-chloride cotransporter (KCC) isoform expression was characterized in corneal epithelial cells (CEC). During exposure to a 50% hypotonic challenge, the RVD response was larger in SV40-immortalized human CEC (HCEC) than in SV40-immortalized rabbit CEC (RCEC). A KCC inhibitor-[(dihydroindenyl)oxy] alkanoic acid (DIOA)-blocked RVD more in HCEC than RCEC. Under isotonic conditions, N-ethylmaleimide (NEM) produced KCC activation and transient cell shrinkage. Both of these changes were greater in HCEC than in RCEC. Immunoblot analysis of HCEC, RCEC, primary human CEC (pHCEC), and primary bovine CEC (BCEC) plasma membrane enriched fractions revealed KCC1, KCC3, and KCC4 isoform expression, whereas KCC2 was undetectable. During a hypotonic challenge, KCC1 membrane content increased more rapidly in HCEC than in RCEC. Such a challenge induced a larger increase and more transient p44/42MAPK activation in HCEC than RCEC. On the other hand, HCEC and RCEC p38MAPK phosphorylation reached peak activations at 2.5 and 15 min, respectively. Only in HCEC, pharmacological manipulation of KCC activity modified the hypotonicity-induced activation of p44/42MAPK, whereas p38MAPK phosphorylation was insensitive to such procedures in both cell lines. Larger increases in HCEC KCC1 membrane protein content correlated with their ability to undergo faster and more complete RVD. Furthermore, pharmacological activation of KCC increased p44/42MAPK phosphorylation in HCEC but not in RCEC, presumably a reflection of low KCC1 membrane expression in RCEC. These findings suggest that KCC1 plays a role in (i) maintaining isotonic steady-state cell volume homeostasis, (ii) recovery of isotonic cell volume after a hypotonic challenge through RVD, and (iii) regulating hypotonicity-induced activation of the p44/42MAPK signaling pathway required for cell proliferation. 相似文献
34.
Weikai Xue Jonas Ogien Pavel Bulkin Anne-Lise Coutrot Arnaud Dubois 《Journal of biomedical optics》2022,27(8)
SignificanceLine-field confocal optical coherence tomography (LC-OCT) is a recently introduced high-resolution imaging modality based on a combination of low-coherence optical interferometry and reflectance confocal optical microscopy with line illumination and line detection. Capable of producing three-dimensional (3D) images of the skin with cellular resolution, in vivo, LC-OCT has been mainly applied in dermatology and dermo-cosmetology. The LC-OCT devices capable of acquiring 3D images reported so far are based on a Linnik interferometer using two identical microscope objectives. In this configuration, LC-OCT cannot be designed to be a very compact and light device, and the image acquisition speed is limited.AimThe objective of this work was to develop a more compact and lighter LC-OCT device that is capable of acquiring images faster without significant degradation of the resolution and with optimized detection sensitivity.ApproachWe developed an LC-OCT device based on a Mirau interferometer using a single objective. Dynamic adjustment of the camera frequency during the depth scan is implemented, using a faster camera and a more powerful light source. The reflectivity of the beam-splitter in the Mirau interferometer was optimized to maximize the detection sensitivity. A galvanometer scanner was incorporated into the device for scanning the illumination line laterally. A stack of adjacent B-scans, constituting a 3D image, can thus be acquired.ResultsThe device is able to acquire and display B-scans at 17 fps. 3D images with a quasi-isotropic resolution of (1.3, 1.9, and in the , and directions, respectively) over a field of () can be obtained. 3D imaging of human skin at cellular resolution, in vivo, is reported.ConclusionsThe acquisition rate of the B-scans, at 17 fps, is unprecedented in LC-OCT. Compared with the conventional LC-OCT devices based on a Linnik interferometer, the reported Mirau-based LC-OCT device can acquire B-scans times faster. With potential advantages in terms of compactness and weight, a Mirau-based device could easily be integrated into a smaller and lighter handheld probe for use by dermatologists in their daily medical practice. 相似文献
35.
Nikolas Kirly Dominika Capkov Miroslav Almi Tom Kazda Ondej ech Pavel udek Andrea Strakov Fedorkov Maxim Lisnichuk Vera Meynen Vladimír Zelek 《RSC advances》2022,12(37):23989
Lithium–sulphur batteries attract increasing interest due to their high theoretical specific capacity, advantageous economy, and “eco-friendliness”. In this study, a metal–organic framework (MOF) GaTCPP containing a porphyrinic base ligand was used as a conductive additive for sulphur. GaTCPP was synthesized, characterized, and post-synthetically modified by the transition metal ions (Co2+/Ni2+). The doping of GaTCPP ensured an increase in the carbon dioxide adsorption capacities, which were measured under different conditions. Post-synthetic modification of GaTCPP with Co2+/Ni2+ ions has been shown to increase carbon dioxide storage capacity from 22.8 wt% for unmodified material to 23.1 wt% and 26.5 wt% at 0 °C and 1 bar for Co2+ and Ni2+-doped analogues, respectively. As a conductive part of cathode material, MOFs displayed successful sulphur capture and encapsulation proven by stable charge/discharge cycle performances, high-capacity retention, and coulombic efficiency. The electrodes with pristine GaTCPP showed a discharge capacity of 699 mA h g−1 at 0.2C in the fiftieth cycle. However, the doping of GaTCPP by Ni2+ has a positive impact on the electrochemical properties, the capacity increased to 778 mA h g−1 in the fiftieth cycle at 0.2C.Metal–porphyrin framework GaTCPP was used for carbon dioxide adsorption and as a host for preparation of a Li–S battery cathode material. 相似文献
36.
37.
Pavel N. Degtyarenko Vladimir V. Zheltov Nikolay N. Balashov Andrey Yu. Arkhangelsky Alena Yu. Degtyarenko Konstantin L. Kovalev 《Materials》2022,15(24)
Numerical calculations of parameters of an electrical power network where an HTS fuse is used as a fault current limiting device have been done. The calculations were performed for networks containing different types of HTS cables as well. The design of HTS fuse was developed based on the numerical calculation for the network-rated parameters considering the special types 2G HTS tape characteristics. The distinctive feature of these tapes is the minimal thickness (about 30 µm) of the substrate at the critical current 450–600 A. The tests were performed at a voltage of 1 kV and demonstrated the ability of circuit breaking at fault currents about 3–4 kA. A comparison of experimental results with the calculations allows us to conclude that the HTS fuse of this design can operate as a fault current limiting device in electrical power networks at various rated voltage levels. 相似文献
38.
Josef Vodicka Jan Geiger Alexandra
idkov Pavel Andrle Hynek Mírka Martin Svaton Tom Kostlivý 《Annals of thoracic and cardiovascular surgery》2022,28(3):171
Purpose: The aims of this work were the retrospective analysis of a cohort of patients with acute mediastinitis treated at the authors’ worksite over a 15-year period and the identification of factors that significantly affect the outcomes of the therapy.Methods: During the period 2006–2020, 80 patients with acute mediastinitis were treated. Within the cohort, the following were observed: the causes and the type of acute mediastinitis, length of anamnesis, comorbidities, diagnostic methods, time from the diagnosis to surgery, types and number of surgical procedures, results of microbiological tests, complications, and outcomes of the treatment.Results: The most common type of acute mediastinitis was descending mediastinitis (48.75%). A total of 116 surgical procedures were performed. Ten patients in the cohort died (12.5%). Patients older than 60 years were at a 6.8 times higher risk of death. Patients with more than two comorbidities were at a 14.3 times higher risk of death. The presence of yeasts in the culture material increased the risk of death by 4.4 times.Conclusion: Early diagnosis, removal of the cause of mediastinitis, sufficient mediastinal debridement, and multiple drainage thereof with the possibility of continual postoperative lavage are essential for the successful treatment of acute mediastinitis. 相似文献
39.
Anna Knaislov Pavel Novk Jií Linhart Ivo Szurman Kateina Skotnicov Jan Juica Tom egan 《Materials》2021,14(4)
Intermetallic compounds based on Ti-Al- (Si) are attractive materials with good thermal stability and low density. However, the production of these materials is quite complicated. Partially modified conventional methods of melting metallurgy are most often used due to availability, possible high productivity, and relatively low production costs. Therefore, some technologies for the production of intermetallics based on Ti-Al are currently available, but with certain disadvantages, which are caused by poor casting properties or extreme reactivity of the melt with crucibles. Some shortcomings can be eliminated by modifying the melting technology, which contributes to increasing the cost of the process. The work deals with the preparation of Ti-Al-Si intermetallic compounds with different contents of aluminum and silicon, which were produced by centrifugal casting in an induction vacuum furnace Linn Supercast-Titan. This process could contribute to the commercial use of these alloys in the future. For this research, the TiAl15Si15(in wt.%) alloy was selected, which represents a balanced ratio of aluminides and silicides in its structure, and the TiAl35Si5 alloy, which due to the lower silicon content allows better melting conditions, especially with regard to the melting temperature. This alloy was also investigated after HIP (“Hot Isostatic Pressing”) treatment. 相似文献
40.
Obese, insulin-resistant patients have been shown to have metabolic inflexibility. The goal of this study was to examine the effect of insulin administration on energy metabolism in lean, type 1 diabetic (DM1) patients. Eleven DM1 patients without vascular complications and 11 healthy controls (C) were examined. We performed a 2-step hyperinsulinemic euglycemic clamp (240 minutes; period 1: 1 mU. kg(-1). min(-1) and period 2: 10 mU. kg(-1). min(-1)) combined with indirect calorimetry during basal period B (B, -45 to 0 minutes), period 1, and period 2 of the clamp. The metabolic clearance rates of glucose (MCR) were lower in DM1 compared with C in period 1 (12.54 +/- 3.38 v 17.41 +/- 6.18 mL. kg(-1). min(-1); P <.02), as well as in period 2 (21.63 +/- 6.47 v 26.61 +/- 4.45 mL. kg(-1). min(-1); P <.05). Basal respiratory quotient (RQ) was lower in DM1 compared with C (0.72 +/- 0.04 v 0.75 +/- 0.04; P <.03). Insulin administration was accompanied by an increase in RQ in both groups, which was lower in DM1 compared with C (period 1: +0.09 +/- 0.04 v +0.11 +/- 0.07; P <.001; period 2: +0.13 +/- 0.04 v +0.16 +/- 0.04; P <.001). Glucose oxidation did not differ between the groups in period B; however, it was lower in DM1 compared with C in periods 1 (1.17 +/- 0.67 v 3.28 +/- 1.11 mg. kg(-1). min(-1); P <.003); and 2 (2.10 +/- 0.64 v 3.28 +/- 0.93 mg. kg(-1). min(-1); P <.009). Lipid oxidation was higher in DM1 in all periods compared with C; period B (3.28 +/- 0.77 v 1.16 +/- 0.55 mg. kg(-1). min(-1); P <.001), period 1 (1.10 +/- 0.41 v 0.67 +/- 0.54 mg. kg(-1). min(-1); P <.05), and period 2 (0.99 +/- 0.29 v 0.52 +/- 0.58 mg. kg(-1). min(-1); P <.01). The groups did not differ in protein oxidation. In conclusion, DM1 patients with secondary insulin resistance (IR) are characterized by metabolic inflexibility manifesting itself by smaller increases in RQ and glucose oxidation after insulin administration during the euglycemic clamp. 相似文献