Raymond Liang

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Eukaryotic cells carry two genomes, nuclear (nDNA) and mitochondrial (mtDNA), which are ostensibly decoupled in their replication, segregation and inheritance. It is increasingly appreciated that heteroplasmy, the occurrence of multiple mtDNA haplotypes in a cell, plays an important biological role, but its features are not well understood. Until now,(More)
Aging hematopoietic stem cells (HSCs) exhibit defective lineage specification that is thought to be central to increased incidence of myeloid malignancies and compromised immune competence in the elderly. Mechanisms underlying these age-related defects remain largely unknown. We show that the deacetylase Sirtuin (SIRT)1 is required for homeostatic HSC(More)
Far-field plume measurements were performed on the X2 nested-channel Hall-effect thruster using a nude Faraday probe, retarding potential analyzer, and E×B probe. Data from these probes were used to examine the operating characteristics of the X2 with both channels operating simultaneously (dual-channel mode). For each operating condition in dual-channel(More)
The X2 nested-channel Hall-effect thruster has been operated at constant discharge powers of 5 kW and 6 kW. Thrust measurements showed that improved performance over an extended range of specific impulse can be obtained by transitions between operating modes of the X2. The simultaneous operation of both channels provided the best performance at low specific(More)
Hematopoietic stem cells (HSC) are primarily dormant but have the potential to become highly active on demand to reconstitute blood. This requires a swift metabolic switch from glycolysis to mitochondrial oxidative phosphorylation. Maintenance of low levels of reactive oxygen species (ROS), a by-product of mitochondrial metabolism, is also necessary for(More)
Eukaryotic cells carry two genomes, nuclear (nDNA) and mitochondrial (mtDNA), which are ostensibly decoupled in their replication, segregation and inheritance. It is increasingly appreciated that heteroplasmy, the occurrence of multiple mtDNA haplotypes in a cell, plays an important biological role, but its features are not well understood. Accurately(More)
show large amplitude bursts of plasma corresponding to the Hall thruster breathing mode as well as inter-channel coupling between the simultaneously discharging nested channels. The time-resolved EEDFs in the plume of the thruster display distributions that are predominantly Maxwellian and contain transient bursts of higher energy electrons that occur with(More)
Floating emissive probe plasma potential maps of the X2 dual nested channel Hall thruster across a triad of operating conditions (inner, outer, and dual channel) at 150 V discharge voltage are presented. The maps extend from the thruster exit plane and thruster centerline to 3.5 mean outer channel radii (OCR) axially and 2.8 OCR radially. Together with(More)
Eukaryotic cells carry two genomes, nuclear (nDNA) and mitochondrial (mtDNA), which are ostensibly decoupled in their replication, segregation and inheritance. It is increasingly appreciated that heteroplasmy, the occurrence of multiple mtDNA haplotypes in a cell, plays an important biological role, but its features are not well understood. Until now,(More)
Circulating red blood cells (RBCs) are essential for tissue oxygenation and homeostasis. Defective terminal erythropoiesis contributes to decreased generation of RBCs in many disorders. Specifically, ineffective nuclear expulsion (enucleation) during terminal maturation is an obstacle to therapeutic RBC production in vitro. To obtain mechanistic insights(More)