Stomata regulate gas exchange and are distributed across the leaf epidermis with characteristic spacing. Arabidopsis stomata are produced by asymmetric cell divisions. Mutations in the gene TOO MANY MOUTHS (TMM) disrupt patterning by randomizing the plane of formative asymmetric divisions and by permitting ectopic divisions. TMM encodes a leucine-rich repeat-containing receptor-like protein exp...

Tiny ultrasonic linear actuators (TULAs) are used in many industrial applications and a full characterization of their dynamic behavior is needed. This paper presents a detailed theoretical-experimental study of TULAs. The general structure and operation principle of TULAs are introduced. The actuator dynamics is then described using a simple piezoelectric model. In practice, TULAs are most oft...

Discussion on improving our knowledge of changes in global poverty and inequality focused on three main questions. First, should international comparisons of living standards across countries use PPP estimates, or market exchange rates to compare the purchasing power of citizens in different countries? Second, if PPP estimates are used, is a single national measure of aggregate PPP adequate to ...

Symmetric and asymmetric divisions are important for self-renewal and differentiation of stem cells during neurogenesis. Although cerebellar granule neurogenesis is controlled by sonic hedgehog (SHH) signaling, whether and how this process is mediated by regulation of cell division modes have not been determined. Here, using time-lapse imaging and cell culture from neuronal progenitor-specific ...

Animal development is a complex and dynamic process orchestrated by exquisitely timed cell lineage commitment, divisions, migration, and morphological changes at the single-cell level. In the past decade, extensive genetic, stem cell, and genomic studies provided crucial insights into molecular underpinnings and the functional importance of genetic pathways governing various cellular differenti...

Precise regulation of stem cell self-renewal/differentiation is essential for embryogenesis and tumor suppression. Drosophila neural progenitors (neuroblasts) align their spindle along an apical/basal polarity axis to generate a self-renewed apical neuroblast and a differentiating basal cell. Here, we genetically disrupt spindle orientation without altering cell polarity to test the role of spi...