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The work is devoted to the study of the second-harmonic generation (SHG) process as a result of random quasi-phase-matching of thulium laser radiation in ZnSe polycrystals. A linear dependence of the SHG efficiency on the nonlinear medium length has been observed in the experiment. The efficiencies of SHG in ZnSe polycrystals with average grain sizes from 35 μ m to 380 μ m were compared. The obtained results are in good agreement with the theory in the case of a Gaussian grain size distribution. [ABSTRACT FROM AUTHOR]

In this study, we investigated autonomous vessel obstacle avoidance using advanced techniques within the Guidance, Navigation, and Control (GNC) framework. We propose a Mixed Integer Linear Programming (MILP) based Guidance system for robust path planning avoiding static and dynamic obstacles. For Navigation, we suggest a multi-modal neural network for perception, demonstrating the identification of obstacle type, position, and orientation using imaging sensors. Additionally, the paper compares an error-based PID control strategy and a Model Predictive Control (MPC) scheme as well. This evaluation aids in better evaluating their performance and determining their applicability within the GNC scheme. We detail the implementation of these systems, present simulation results, and offer a performance evaluation using an experimental dataset. Our findings, analysed through qualitative discussion and quantitative performance indicators, contribute to advancements in autonomous navigation and the control strategies to achieve it. [ABSTRACT FROM AUTHOR]

The current study is dedicated to measuring the Verdet constant of pure and chromium and iron ions doped ZnSe using laser sources in the range from 632.8 to 2430 nm. An increase in the magneto-optical properties of ZnSe as a result of diffusion doping with transition metal ions was experimentally discovered. The results align with the Van Vleck-Hebb theory, which predicts a nearly linear rise in the Verdet constant with increasing of transition element concentration. [ABSTRACT FROM AUTHOR]

A large number of modern functional single crystals of the middle category belong to gyrotropic media. In these crystals, when light propagates along the optical axis, rotation of the plane of its polarization is observed. In this study a spectrophotometric method is used to obtain the dispersion dependences of the rotation angle of the polarization plane. This method is based on measuring the intensity of the light passing through the polarizer–crystal–analyzer system. The crystal is a polished plane-parallel plate of a uniaxial gyrotropic crystal cut perpendicularly to the optical axis. Measurements are carried out on a Cary-5000 UV-Vis-NIR spectrophotometer in the wavelength range of 200–1200 nm using polarizers Glan–Taylor prisms. Polished plane-parallel plates of known SiO2 and α-LiIO3 crystals are used as samples. The obtained dispersion dependences of the spectral transmission coefficients have an oscillating character. The discrete values of the specific angles of rotation of the plane of polarization of light are calculated from the extrema on these dependences. These discrete values can be approximated by the Drude, Chandrasekhar, and Vyshin formulas, depending on what determines the nature of the rotational ability of the plane of polarization of light in each particular material. For the studied crystals the dependences of the modified Drude formula of the form 1/ρ = f(λ2), which should have a linear character in the case of an ideal crystal, are plotted. The obtained experimental results are closely correlated to the available published data. The advantages of this method lie in its efficiency, the possibility of obtaining dispersion dependences of the specific rotation angle of the polarization plane, the need for a single sample, the possibility of assessing the nature of the rotational ability of specific crystals, and the possibility of evaluating the structural perfection of the studied crystals. [ABSTRACT FROM AUTHOR]

This clinical report describes the rehabilitation of an edentulous mandible with an implant-supported fixed prosthesis using an all-ceramic framework fabricated from zirconium oxide. Four interforaminal implants were inserted and allowed to heal submerged. The implant-supported fixed prosthesis was then fabricated using CAD/CAM and electroforming technology. No clinical complications were observed at the 6-month follow-up examination, and the patient was highly satisfied with function and esthetics. All-ceramic frameworks provide a high standard of esthetics; reduce the number of metals used in the oral cavity; and have a lower density compared to metals, which reduces weight in the case of large frameworks. [ABSTRACT FROM AUTHOR]

A conservative method of replacing missing teeth is described. The fixed partial denture incorporates a resin-bonded retainer for the intact tooth and a telescopic coping for the carious or fractured tooth. A permanently cemented coping beneath a provisionally cemented superstructure provides the opportunity to recement the prosthesis if the acid-etched retainer is debonded. The advantages of this technique include conservation of enamel on the intact abutment and protection from leakage caused by dissolution of temporary cement on the abutment with a telescopic coping. [ABSTRACT FROM AUTHOR]

Background There is strong evidence that drug-induced cutaneous eruptions have an immunological component. Interleukin ( IL)-17, a proinflammatory cytokine that is predominantly produced by T helper 17 cells, has been linked to various autoimmune and inflammatory diseases. Aim To measure serum IL-17 levels in patients with cutaneous drug reactions [erythema multiforme ( EM) and Stevens-Johnson syndrome/toxic epidermal necrolysis ( SJS/ TEN)] in order to study the associations between IL-17 and disease severity. Methods In total, 32 patients (13 with EM and 19 with SJS/ TEN) and 15 age- and sex-matched healthy controls ( HCs) were enrolled. Patients with SJS/ TEN were assessed clinically using the SCORe of Toxic Epidermal Necrosis ( SCORTEN) scale. Serum IL-17 levels were determined by ELISA. Results Serum IL-17 levels were significantly higher compared with HCs (16.46 ± 5.21 pg/ mL) in the EM (35.1 ± 23.89 pg/ mL, P < 0.02) and SJS/ TEN (68.19 ± 35.42 pg/ mL, P = 0.001) groups. IL-17 levels were also significantly higher in the SJS/ TEN group than in the EM group ( P = 0.004). Mean affected body surface area percentage was 0.9 ± 0.21 in the EM group and 22.8 ± 10.67 in the SJS/ TEN group. The SJS/ TEN SCORTEN ranged from 1 to 5, with a mean of 2.5 ± 1. Serum IL-17 level correlated positively with both percentage surface area of detached skin and SCORTEN. Conclusions Serum IL-17 levels may have prognostic and diagnostic value in patients with EM or SJS/TEN reactions, and can provide a valuable approach in managment. [ABSTRACT FROM AUTHOR]

We aimed to understand the underlying mechanism that regulates successively expressed cuticular protein (CP) genes around pupation in Bombyx mori. Quantitative PCR was conducted to clarify the expression profile of CP genes and ecdysone-responsive transcription factor (ERTF) genes around pupation. Ecdysone pulse treatment was also conducted to compare the developmental profiles and the ecdysone induction of the CP and ERTF genes. Fifty-two CP genes (RR-1 13, RR-2 18, CPG 8, CPT 3, CPFL 2, CPH 8) in wing discs of B. mori were examined. Different expression profiles were found, which suggests the existence of a mechanism that regulates CP genes. We divided the genes into five groups according to their peak stages of expression. RR-2 genes were expressed until the day of pupation and RR-1 genes were expressed before and after pupation and for longer than RR-2 genes; this suggests different construction of exo- and endocuticular layers. CPG, CPT, CPFL and CPH genes were expressed before and after pupation, which implies their involvement in both cuticular layers. Expression profiles of ERTFs corresponded with previous reports. Ecdysone pulse treatment showed that the induction of CP and ERTF genes in vitro reflected developmental expression, from which we speculated that ERTFs regulate CP gene expression around pupation. [ABSTRACT FROM AUTHOR]

Reports on the introduction of severe acute respiratory syndrome (SARS) in Toronto, Ontario during 2003 and the resulting outbreak at several Greater Toronto Area hospitals. Discussion of public health measures to prevent the transmission of SARS-associated coronavirus among health-care workers and the second outbreak about four weeks after the first, which was thought to be over; The CDC editorial note discussing the importance of controlling health-care-related SARS transmission and deciding when SARS precautions are necessary.