Morphological parametric mapping of 21 skin sites throughout the body using optical coherence tomography

Background Changes in body posture cause changes in morphological properties at different skin sites. Although previous studies have reported the thickness of the skin, the details of the postures are not generally given. This paper presents the effect of a change in posture on parameters such as thickness and surface roughness in 21 load-bearing and non-load-bearing sites. Materials and methods A total of 12 volunteers (8 males and 4 females) were selected in an age group of 18–35 years and of Fitzpatrick skin type I-III. Images were captured using a clinically-approved VivoSight® optical coherence tomography system and analysed using an algorithm provided by Michelson Diagnostics. Results Overextension (extending joints to full capacity) resulted in changes to thickness, roughness and undulation of the skin around the body. Discussion and conclusion The load-bearing regions have thicker skin compared to non-load-bearing sites. This is the first time that undulation topography of the stratum corneum–stratum lucidum and the dermal–epidermal junction layers have been measured and reported using statistical values such as Ra. The data presented could help to define new skin layer models and to determine the variability of the skin around the body and between participants

Visible-light optical coherence tomography platform for the characterization of the skin barrier

We demonstrate a free-space, trolley-mountable Fourier domain visible-light optical coherence tomography (OCT) system for studying the stratum corneum in non-palmar human skin. An axial resolution of 1 µm in tissue and at least −75 dB sensitivity have been achieved. High-quality B-scans, containing 1600 A-scans, are acquired at a rate of 39 Hz. Images from the dorsal hand, ventral wrist and ventral forearm areas are obtained, with a clearly resolved stratum corneum layer (typically 5–15 µm thick) presenting as a hypoechogenic dark layer below the bright entrance signal, similar to that found in palmar skin with traditional OCT systems. We find that the appearance of the stratum corneum layer strongly depends on its water content, becoming brighter after occlusive hydration

Search for the semi-leptonic decays Λc+→Λπ+π−e+νe and Λc+→pKS0π−e+νe

We search for the semi-leptonic decays Λc+→Λπ+π−e+νe and Λc+→pKS0π−e+νe in a sample of 4.5fb−1 of e+e− annihilation data collected in the center-of-mass energy region between 4.600GeV and 4.699GeV by the BESIII detector at the BEPCII. No significant signals are observed, and the upper limits on the decay branching fractions are set to be B(Λc+→Λπ+π−e+νe)<3.9×10−4 and B(Λc+→pKS0π−e+νe)<3.3×10−4 at the 90% confidence level, respectively

Search for an axion-like particle in radiative J/ψ decays

We search for an axion-like particle (ALP) a through the process ψ(3686)→π+π−J/ψ, J/ψ→γa, a→γγ in a data sample of (2.71±0.01)×109 ψ(3686) events collected by the BESIII detector. No significant ALP signal is observed over the expected background, and the upper limits on the branching fraction of the decay J/ψ→γa and the ALP-photon coupling constant gaγγ are set at 95% confidence level in the mass range of 0.165≤ma≤2.84GeV/c2. The limits on B(J/ψ→γa) range from 8.3×10−8 to 1.8×10−6 over the search region, and the constraints on the ALP-photon coupling are the most stringent to date for 0.165≤ma≤1.468GeV/c2