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Context: The major aim of tissue engineering is inducing of the body's mechanisms to regenerate damaged tissues to original condition and task. Scaffolds are 3D porous constructs which provide a cellular microenvironment needed for tissue engineering. Choosing a biomaterial with proper biological, physical, and mechanical properties is of great importance in tooth tissue engineering. Thus, the current study reviews the properties of different polymers and ceramics for use as scaffolds in tooth dental regeneration. Evidence Acquisition: The current study searched databases such as Elsevier, Wiley, Google Scholar, and PubMed in English from 1972 to 2018. After going through the required process, 29 articles were eventually confirmed and enrolled in this review paper. Conclusions: The results of this work confirmed that thanks to having the ability to provide suitable amounts of interconnected porosities, high ratio of surface area to volume, proper mechanical strength, and different geometries required for tissue engineering, polymers are a good option for regeneration of tooth tissues. Although bioceramics such as calcium phosphate and glasses have good biocompatibility and bioactivity, their poor mechanical properties and low degradation rate limit their extensive use in tooth tissue regeneration.

Malignant melanoma (MM) of mucosal membranes (excluding anus and head-neck) is a rare but aggressive disease with poor outcomes. The knowledge of this tumor's development, etiology, and management is scarce, mainly due to the low case numbers. We presented eight cases and performed a comprehensive literature review on mucosal MM (between 1970 and 2020). We identified 47 manuscripts on 55 patients with primary mucosal MM (limited to urothelium and vagina) and reviewed demographics, tumor specifications (morphology, stage, etc.), management, and survival. We identified 10 manuscripts discussing treatment in 1595 mucosal and non-mucosal MM and extracted the data regarding the non-surgical treatment modalities of mucosal MM patients.In 63 cases, 48 tumors primarily occurred in the urothelium (urethra: 47, bladder: 1) and 15 in the vagina. Molecular studies in a subset of cases revealed alterations in c-KIT, NRAS, BRAF (non-V600E and V600E), TP53, and NF1. Fifty-three patients underwent surgery (with additional chemotherapy, immunotherapy, and radiotherapy in 19, eight, and eight patients, respectively). The outcome was available in 52 cases, showing 21 deaths, 10 without recurrence, two alive with disease, and five lost to follow-up. Shared genetic signatures in mucosal and skin MM suggest a similar development mechanism; however, unlike skin MM, there are less BRAF mutations and more PI3K/AKT/mTOR pathway alterations in mucosal MM. Prolonged chemotherapy (i.e., methotrexate) and immune-modulating agents (i.e., natalizumab) may be risk factors. The stage at diagnosis and proper surgical extirpation are keys to the prognosis and survival of patients.

Colour vision represents a vital aspect of perception that ultimately enables a wide variety of species to thrive in the natural world. However, unified methods for constructing chromatic visual stimuli in a laboratory setting are lacking. Here, we present stimulus design methods and an accompanying programming package to efficiently probe the colour space of any species in which the photoreceptor spectral sensitivities are known. Our hardware-agnostic approach incorporates photoreceptor models within the framework of the principle of univariance. This enables experimenters to identify the most effective way to combine multiple light sources to create desired distributions of light, and thus easily construct relevant stimuli for mapping the colour space of an organism. We include methodology to handle uncertainty of photoreceptor spectral sensitivity as well as to optimally reconstruct hyperspectral images given recent hardware advances. Our methods support broad applications in colour vision science and provide a framework for uniform stimulus designs across experimental systems. This article is part of the theme issue ‘Understanding colour vision: molecular, physiological, neuronal and behavioural studies in arthropods’.

Recent advances in neurophysiological methods are providing IS researchers with new research opportunities. We deployed electroencephalograms (EEG) analyses to compare learning within two organizational forms: computer-mediated and face-toface decision teams. We collected demographic, psychometric, simultaneous parallel EEG, and performance data from 118 undergraduate students who performed the Ethical Decision Challenge© as part of a face-to-face or a computer-mediated team. Organizational learning was derived from performance data registered at three points during the experiment:(1) individually prior to group discussion, (2) collectively as a group consensus, and (3) individually following the group discussion. The results revealed a significant difference between learning ability between face-to-face and computer-mediated team members; thus supporting propositions of media richness theory. Further, a comparison of brain patterns between face-to-face team members and computer-mediated team members revealed a significant difference in neural activity. Our findings also confirm the role of the left temporal lobe in learning and performance.