Abstract
In this paper, we describe the study of the kinetics and efficiency of the refractive index matching mechanism created by highly concentrated glycerol solutions in human normal and pathological colorectal mucosa tissues. Considering thewavelength range between 200 and 1000 nm, higher efficiency was obtained for the pathological mucosa, which shows a decreasing efficiency with increasing wavelength. The normal mucosa presents similar values in the deep-ultraviolet and in the near-infrared. Minimal efficiency values of 1% and 1.5% were obtained in the normal and pathological mucosa at 266 nm (combined absorption of DNA/RNA and myoglobin/hemoglobin bands at 260 and 274 nm) and local maxima of 2.9% and 3.8% were obtained in the same tissues at 570 nm. The diffusion time of glycerol was estimated as 417.3 +/- 5.2 s in normal mucosa and 504.9 +/- 3.8 s in pathological mucosa, suggesting that less molecules are necessary in the pathological tissue to produce a higher magnitude RI matching.

Abstract
In this paper, we describe the combination of ultraviolet (UV) spectroscopy with the optical clearing technique to induce new tissue windows, evaluate their efficiency, study the diffusion properties of agents and discriminate cancer. The use of highly concentrated glycerol solutions has induced high efficiency clearing effects in the UV, both in human colorectal and gingival tissues. The protein dissociation rate obtained for colorectal tissues was approximately 3 times higher in pathological than in normal mucosa and the kinetics of diffuse reflectance in the UV allowed to estimate the diffusion coefficient for water in gingival mucosa at glycerol action as (1.78 +/- 0.26) x 10(-6) cm(2)/s.

Abstract

Abstract
Background: The American Academy of Sleep Medicine guidelines suggest that clinical prediction algorithms can be used in patients with obstructive sleep apnea (OSA) without replacing polysomnography, which is the gold standard. Objective: This study aims to develop a clinical decision support system for OSA diagnosis according to its standard definition (apnea-hypopnea index plus symptoms), identifying individuals with high pretest probability based on risk and diagnostic factors. Methods: A total of 47 predictive variables were extracted from a cohort of patients who underwent polysomnography. A total of 14 variables that were univariately significant were then used to compute the distance between patients with OSA, defining a hierarchical clustering structure from which patient phenotypes were derived and described. Affinity from individuals at risk of OSA phenotypes was later computed, and cluster membership was used as an additional predictor in a Bayesian network classifier (model B). Results: A total of 318 patients at risk were included, of whom 207 (65.1%) individuals were diagnosed with OSA (111, 53.6% with mild; 50, 24.2% with moderate; and 46, 22.2% with severe). On the basis of predictive variables, 3 phenotypes were defined (74/207, 35.7% low; 104/207, 50.2% medium; and 29/207, 14.1% high), with an increasing prevalence of symptoms and comorbidities, the latter describing older and obese patients, and a substantial increase in some comorbidities, suggesting their beneficial use as combined predictors (median apnea-hypopnea indices of 10, 14, and 31, respectively). Cross-validation results demonstrated that the inclusion of OSA phenotypes as an adjusting predictor in a Bayesian classifier improved screening specificity (26%, 95% CI 24-29, to 38%, 95% CI 35-40) while maintaining a high sensitivity (93%, 95% CI 91-95), with model B doubling the diagnostic model effectiveness (diagnostic odds ratio of 8.14). Conclusions: Defined OSA phenotypes are a sensitive tool that enhances our understanding of the disease and allows the derivation of a predictive algorithm that can clearly outperform symptom-based guideline recommendations as a rule-out approach for screening.

Abstract
Hexapods are very common in astronomy as a mechanism to provide a stiff mount or a precision alignment tool. Here, we present a lumped model for a general symmetric hexapod that allows us to compute the load distribution under external forces, the hexapod's resolution, and the identification of singularity loci within the workspace. We also developed a script to analyze this parametric model, which is publicly available. We use this model to develop and design a hexapod for mid-infrared ELT imager and spectrograph, one of the extremely large telescope's first light instruments. The designed hexapod solution can survive strict earthquake conditions that can go up to 5g, and position and align the 11 ton instrument with submillimetric and arcsecond precisions. Although the model presented is not as precise or as realistic as a finite element WO analysis, it provides, in a fraction of a second, a very good first approximation. Therefore, unlike Eh methods, the model is able to study many geometries in a short time. (C) 2021 Society of Photo-Optical Instrumentation Engineers (SPIE)

Abstract
Context. Close young binary stars are unique laboratories for the direct measurement of pre-main-sequence (PMS) stellar masses and their comparison to evolutionary theoretical models. At the same time, a precise knowledge of their orbital parameters when still in the PMS phase offers an excellent opportunity for understanding the influence of dynamical effects on the morphology and lifetime of the circumstellar as well as circumbinary material. Aims. The young T Tauri star WW Cha was recently proposed to be a close binary object with strong infrared and submillimeter excess associated with circum-system emission, which makes it dynamically a very interesting source in the above context. The goal of this work is to determine the astrometric orbit and the stellar properties of WW Cha using multi-epoch interferometric observations. Methods. We derive the relative astrometric positions and flux ratios of the stellar companion in WW Cha from the interferometric model fitting of observations made with the VLTI instruments AMBER, PIONIER, and GRAVITY in the near-infrared from 2011 to 2020. For two epochs, the resulting uv-coverage in spatial frequencies permits us to perform the first image reconstruction of the system in the K band. The positions of nine epochs are used to determine the orbital elements and the total mass of the system. Combining the orbital solution with distance measurements from Gaia DR2 and the analysis of evolutionary tracks, we constrain the mass ratio. Results. We find the secondary star orbiting the primary with a period of T = 206.55 days, a semimajor axis of a = 1.01 au, and a relatively high eccentricity of e = 0.45. The dynamical mass of M-tot = 3.20 M-circle dot can be explained by a mass ratio between similar to 0.5 and 1, indicating an intermediate-mass T Tauri classification for both components. The orbital angular momentum vector is in close alignment with the angular momentum vector of the outer disk as measured by ALMA and SPHERE, resulting in a small mutual disk inclination. The analysis of the relative photometry suggests the presence of infrared excess surviving in the system and likely originating from truncated circumstellar disks. The flux ratio between the two components appears variable, in particular in the K band, and may hint at periods of triggered higher and lower accretion or changes in the disks' structures. Conclusions. The knowledge of the orbital parameters, combined with a relatively short period, makes WW Cha an ideal target for studying the interaction of a close young T Tauri binary with its surrounding material, such as time-dependent accretion phenomena. Finding WW Cha to be composed of two (probably similar) stars led us to reevaluate the mass of WW Cha, which had been previously derived under the assumption of a single star. This work illustrates the potential of long baseline interferometry to precisely characterize close young binary stars separated by a few astronomical units. Finally, when combined with radial velocity measurements, individual stellar masses can be derived and used to calibrate theoretical PMS models.