Imaging the tarsal plate: A Mini-Review

Imaging the tarsal plate and the meibomian glands (MG) grants new opportunities for ophthalmic practitioners who work in the field of the ocular surface and dry eye across the globe. The secretory role of MG plays a fundamental part in protecting the moisture in front of the eye surface by creating an active shield made of meibum (lipid) which prevents tear evaporation and causes dry eye. Evidence from the most popular Dry Eye Workshop reports (2007 and 2016) demonstrate that MG dysfunction is the first cause of evaporative dry eye which is also the most common cause of dry eye and ocular surface discomfort. Fortunately, during the last years, a plethora of new devices for MG observation, diagnosis and follow-up have been made available in the market. These devices range from invasive to minimally invasive, high to low-tech and from being expensive to low-cost. The objective of this mini-review is to condense the latest evidence in MG imaging by providing a narrative overview on the most common technologies plus some other newer aspects which might guide clinicians and researchers in the field of the ocular surface and dry eye.

Investigations of Muon Flux Variations Detected Using Veto Detectors of the Digital Gamma-rays Spectrometer

This paper presents the results of cosmic ray muons flux monitoring registered by a digital gamma-ray spectrometer’s active shield made of five large plastic scintillators. In traditional, i.e., analogue active shields working in anticoincidence mode with germanium detectors, the generated data are used only as a gating signal and are not stored. However, thanks to digital acquisition applied in designed novel gamma-ray spectrometers enabling offline studies, it has not only become possible to use generated data to reduce the germanium detector background (cosmic rays veto system) but also to initialize long-term monitoring of the muon flux intensity. Furthermore, various analyses methods prove the relevance of the acquired data. Fourier analyses revealed the presence of daily (24 h), near-monthly (27 days) and over bi-monthly (68 days) cycles.

Low-background, digital gamma-ray spectrometer with BEGe detector and active shield: commissioning, optimisation and software development

This paper presents results of the development process of low-background, digital gamma-rays spectrometer equipped with Broad Energy Germanium detector (CANBERRA BE5030), multi-layer passive shield and cosmic veto system that consists of five plastic scintillators (SCIONIX EJ-200). Data acquisition is performed using digitizer CAEN DT5725 with CoMPASS software. Output data analysis is carried out with purposely written and developed code VETO. On the basis of conducted tests, acquisition parameters were set up and tuned as well as time delays between all detectors were established. As a result of the configuration process, the mean background counts reduction of 64% in the whole spectrum and 65% in annihilation peak were achieved. This procedure allowed diminishing detection limits of selected isotopes 37% on average.