Weighted Geometric Mean (WGM) method: A new chromatic adaptation model.

The human visual system has undergone evolutionary changes to develop sophisticated mechanisms that enable stable color perception under varying illumination. These mechanisms are known as chromatic adaptation, a fundamental aspect of color vision. Chromatic adaptation can be divided into two categories: sensory adaptation, which involves automatic adjustments in the visual system, such as retinal gain control, in response to changes in the stimulus, and cognitive adaptation, which depends on the observer's knowledge of the scene and context.

Deriving and dissecting an equally bright reference boundary.

The Helmholtz-Kohlrausch effect signifies the discrepancy between brightness as a perceptual attribute and luminance as a physical metric across different chromaticities. Based on the concepts of brilliance and zero grayness proposed by Ralph Evans, equally bright colors were collected in Experiment 1 by asking observers to adjust the luminance for a given chromaticity to the glowing threshold. The Helmholtz-Kohlrausch effect is thus automatically incorporated.

Representing color as multiple independent scales: brightness versus saturation.

The concept of color space has served as a basis for vast scientific inquiries into the representation of color, including colorimetry, psychology, and neuroscience. However, the ideal color space that can model color appearance attributes and color difference as a uniform Euclidean space is still, to our best knowledge, not yet available. In this work, based on the alternative representation of independent 1D color scales, the brightness and saturation scales for five Munsell principal hues were collected via partition scaling, where the MacAdam optimal colors served as anchors.

Transcription factor induction of vascular blood stem cell niches in vivo.

The hematopoietic niche is a supportive microenvironment composed of distinct cell types, including specialized vascular endothelial cells that directly interact with hematopoietic stem and progenitor cells (HSPCs). The molecular factors that specify niche endothelial cells and orchestrate HSPC homeostasis remain largely unknown. Using multi-dimensional gene expression and chromatin accessibility analyses in zebrafish, we define a conserved gene expression signature and cis-regulatory landscape that are unique to sinusoidal endothelial cells in the HSPC niche.