Hydrogels are commonly used biomaterials for tissue engineering. With their high-water content, good biocompatibility and biodegradability they resemble the natural extracellular environment and have been widely used as scaffolds for 3D cell culture and studies of cell biology. The possible size of such hydrogel constructs with embedded cells is limited by the cellular demand for oxygen and nutrients. For the fabrication of large and complex tissue constructs, vascular structures become necessary within the hydrogels to supply the encapsulated cells. In this review, we discuss the types of hydrogels that are currently used for the fabrication of constructs with embedded vascular networks, the key properties of hydrogels needed for this purpose and current techniques to engineer perfusable vascular structures into these hydrogels. We then discuss directions for future research aimed at engineering of vascularized tissue for implantation.

Introduction The aim of this study was to evaluate the esthetic and sensory outcomes after reconstruction of finger pulp defects with free toe flaps from the lateral aspect of the great toe. Methods From June 2006 to October 2011, we performed 48 free toe pulp transfers for finger pulp reconstruction in 43 patients; 18 male and 25 female patients with a mean age of 31.8 years (range, 16–47 years). Six patients suffered multiple digital pulp defects and five received two synchronous pulp transfers. The defects involved 20 thumbs, 15 index fingers, 10 long fingers, and 4 ring fingers, and flap size ranged from 24 × 18 to 55 × 30 mm. Follow-up evaluation included the functional and esthetic outcomes of the reconstructed pulps and donor toes. Results All but one flap survived completely. Overall, 32 cases (35 pulp flaps) were followed for more than 1 year (range, 12–48 months; average, 22.8 months). The Semmes–Weinstein sensitivity score was 2.83 to 4.74 at the flaps and the mean static two-point discrimination was 6.17 mm (range, 3–10 mm). A total of 13 patients (40.6%) experienced mild (10 cases) to moderate (3 cases) cold intolerance, and 1 patient (3.1%) suffered severe cold intolerance. According to the Michigan Hand Outcome Questionnaire the mean esthetic appearance score was 16 (range, 12–19). Conclusion The free neurovascular great toe pulp flap is an efficient and reliable flap for the reconstruction of finger pulp defects.

Computer audition (CA) has experienced a fast development in the past decades by leveraging advanced signal processing and machine learning techniques. In particular, for its noninvasive and ubiquitous character by nature, CA-based applications in healthcare have increasingly attracted attention in recent years. During the tough time of the global crisis caused by the coronavirus disease 2019 (COVID-19), scientists and engineers in data science have collaborated to think of novel ways in prevention, diagnosis, treatment, tracking, and management of this global pandemic. On the one hand, we have witnessed the power of 5G, Internet of Things, big data, computer vision, and artificial intelligence in applications of epidemiology modeling, drug and/or vaccine finding and designing, fast CT screening, and quarantine management. On the other hand, relevant studies in exploring the capacity of CA are extremely lacking and underestimated. To this end, we propose a novel multitask speech corpus for COVID-19 research usage. We collected 51 confirmed COVID-19 patients’ in-the-wild speech data in Wuhan city, China. We define three main tasks in this corpus, i.e., three-category classification tasks for evaluating the physical and/or mental status of patients, i.e., sleep quality, fatigue, and anxiety. The benchmarks are given by using both classic machine learning methods and state-of-the-art deep learning techniques. We believe this study and corpus cannot only facilitate the ongoing research on using data science to fight against COVID-19, but also the monitoring of contagious diseases for general purpose.