NIR Microscopy Possibilities for the Visualization of Silicon Microelectronic Structure Topology through the Substrate

AbstractExperimental setup based on visible and NIR spectral range microscope with laser port and picosecond laser is developed for silicon integrated circuit (IC) failure analysis. The possibility of visualizing the topology of the submicron technology silicon structures from the back side of the crystal through the substrate is shown. Main features of new setup are demonstrated by some results of backside focused pulsed laser beam initiated latchup effect study. The possibility of the localization of the latchup sensitive areas under focused laser irradiation is shown. NIR light emission accompanying the latchup effect is observed and analyzed. The practical aspects of NIR microscopy for failure analysis under backside laser irradiation are discussed

The dynamics of the non-heme iron in bacterial reaction centers from Rhodobacter sphaeroides

AbstractWe investigate the dynamical properties of the non-heme iron (NHFe) in His-tagged photosynthetic bacterial reaction centers (RCs) isolated from Rhodobacter (Rb.) sphaeroides. Mössbauer spectroscopy and nuclear inelastic scattering of synchrotron radiation (NIS) were applied to monitor the arrangement and flexibility of the NHFe binding site. In His-tagged RCs, NHFe was stabilized only in a high spin ferrous state. Its hyperfine parameters (IS=1.06±0.01mm/s and QS=2.12±0.01mm/s), and Debye temperature (θD0~167K) are comparable to those detected for the high spin state of NHFe in non-His-tagged RCs. For the first time, pure vibrational modes characteristic of NHFe in a high spin ferrous state are revealed. The vibrational density of states (DOS) shows some maxima between 22 and 33meV, 33 and 42meV, and 53 and 60meV and a very sharp one at 44.5meV. In addition, we observe a large contribution of vibrational modes at low energies. This iron atom is directly connected to the protein matrix via all its ligands, and it is therefore extremely sensitive to the collective motions of the RC protein core. A comparison of the DOS spectra of His-tagged and non-His-tagged RCs from Rb. sphaeroides shows that in the latter case the spectrum was overlapped by the vibrations of the heme iron of residual cytochrome c2, and a low spin state of NHFe in addition to its high spin one. This enabled us to pin-point vibrations characteristic for the low spin state of NHFe

M\"ossbauer, nuclear inelastic scattering and density functional studies on the second metastable state of Na2[Fe(CN)5NO]⋅\cdot2H2O

The structure of the light-induced metastable state SII of Na2[Fe(CN)5NO]$\cdot$2H2O 14 was investigated by transmission M\"ossbauer spectroscopy (TMS) in the temperature range 15 between 85 and 135 K, nuclear inelastic scattering (NIS) at 98 K using synchrotron 16 radiation and density functional theory (DFT) calculations. The DFT and TMS results 17 strongly support the view that the NO group in SII takes a side-on molecular orientation 18 and, further, is dynamically displaced from one eclipsed, via a staggered, to a second 19 eclipsed orientation. The population conditions for generating SII are optimal for 20 measurements by TMS, yet they are modest for accumulating NIS spectra. Optimization 21 of population conditions for NIS measurements is discussed and new NIS experiments on 22 SII are proposed

Dynamics of Metal Centers Monitored by Nuclear Inelastic Scattering

Nuclear inelastic scattering of synchrotron radiation has been used now since 10 years as a tool for vibrational spectroscopy. This method has turned out especially useful in case of large molecules that contain a M\"ossbauer active metal center. Recent applications to iron-sulfur proteins, to iron(II) spin crossover complexes and to tin-DNA complexes are discussed. Special emphasis is given to the combination of nuclear inelastic scattering and density functional calculations

A case of successful treatment of tracheoesophageal fistula using laser exposure [Случай успешного лечения трахеопищеводного свища с использованием лазерного воздействия]

The study objective - to present a unique clinical observation of the successful treatment of tracheoesophageal fistula using laser exposure. Case report. patient H., 51 years old, applied to the moscow City Oncology Hospital No 62, moscow Healthсare Department on January 22, 2018, with a diagnosis of thyroid cancer (multicentric growth), T3N0m0 (hospital No. 1974/43). Thyroidectomy was performed on 03.08.2009, removal of a recurrent tumor with resection of the esophageal wall and trachea - 03.02.2021. Histological examination No. 5589/56662-56668 dated 09.02.2021: papillary cancer with invasion of the wall of the esophagus and trachea. Resection within unaltered tissues. A mobilized sternocleidomastoid muscle was used to separate the esophagus and trachea. A nasogastric tube was used for 14 days. The wound on the neck healed by primary intention. The patient began to eat through the mouth. A day after the removal of the probe, facial emphysema began to grow intensively, which was accompanied by a cough. The nasogastric tube is reinserted. with fluoroscopy of the esophagus and with pharyngogastroduodenoscopy, a tracheoesophageal fistula was revealed along the right lateral wall of the trachea, about 0.5 cm in size, 1.5-2 cm below the level of the vocal folds. On endoscopic examination a week later, the fistula was already 1.0 cm in size. Conservative therapy and surgical treatment were carried out. Due to the flexible laser fiber, a phased effect on the fistula wall was carried out, both from the esophagus and from the trachea. within a week after the first session, the fistulous opening decreased by 2 times. Then 2 more sessions were carried out with an interval of 10 days. During endoscopic examination from 05.05.2021 the fistula between the trachea and the esophagus is not defined. The mucous membrane is epithelized, smooth. Swallowing is free. Conclusion. Thus, the problem of treating patients with tracheoesophageal fistulas is extremely complex and versatile. The localization of the fistula, its size, and the clinic's capabilities for treating a patient are of great importance. © 2022 Opuholi Golovy i Sei. All rights reserved