Photo-thermo-refractive (PTR) glass is a photosensitive multi-component silicate glass that is commercially used for the recording of volume holographic elements and finds many applications in advanced laser systems. Refractive index decrement in this glass is observed after UV exposure followed by thermal development. This procedure also causes the appearance of Ag-containing particles that ca...

Pilomatrixoma, also known as pilomatricoma, is a benign tumor that originates from the matrix of the hair root. It usually presents as a single, slow-growing subcutaneous or intradermal firm nodule with a general size of less than 3 centimeters (cm) in diameter. However, giant pilomatrixomas (more than 5 cm) have been reported infrequently. It is more common in females and usually presents duri...

As we begin a new year and new work with the Illinois Community College Board (ICCB), we are thrilled to see our PTR Year Two: Implementation Communities’ teams get their project work up and running. Designed to transform student outcomes and share their innovations and successes with their colleagues across the state, these grassroots teams are using their data and evidence-based practices to ...

Tandem repetitions in protein sequence and structure is a fascinating subject of research which has been a focus of study since the late 1990s. In this survey, we give an overview on the multi-faceted aspects of research on protein tandem repeats (PTR for short), including prediction algorithms, databases, early classification efforts, mechanisms of PTR formation and evolution, and synthetic PT...

A three-year-old boy presented to our oculoplastic clinic with complaints of painless gradually increasing right upper lid mass for the last 6 months. On examination a firm mass measuring roughly 1x1 cm was present on the upper lid. The mass was non tender with fine superficial vessels running over it. A differential diagnosis of epidermoid cyst, vascular malformation, pilomatrixoma, and juveni...