Active size control of condensates by a kinase-based mechanism.

A possible mechanism of phenotypic expression of normal and dystrophic genomes on succinic dehydrogenase activity and fiber size within a single myofiber of muscle transplants

Gold nanoparticles (Au NPs) are unique catalysts due to their increased coordination unsaturation via nanoparticulation. Effective functioning requires an appropriate support to maintain particle dispersion without compromising nanoscale properties. Cross‐linked hydrophilic polymer‐derived hydrogels are ideal supports, particularly for biological and biomedical reactions, due to their aqueous affinity and biocompatibility. However, applications in confined spaces, such as in vivo environments, necessitate hydrogel micronization. This study introduces microsized DNA hydrogels as support for Au catalysts. DNA motif‐composed hydrogel particles exhibit high crosslinking density and produce small Au NPs owing to short DNA strands. This system significantly enhances catalytic efficiency compared to similar‐sized Au NP gel‐supported catalysts and requires minimal gold catalyst. Modulating DNA hydrogel crosslinking density allows easy control of Au NP size and catalytic activity, further improved by increased hydrogel surface area through microparticulation. These findings demonstrate DNA nanotechnology's versatility in tailoring DNA hydrogel properties and Au NP catalytic behavior. Computer‐aided design enables precise particle property and motif arrangement manipulation, offering promising customizable catalytic systems.

cGMP-inhibited cAMP phosphodiesterase 3A (PDE3A) is expressed in mouse oocytes, and its function is indispensable for meiotic maturation as demonstrated by genetic ablation. Moreover, PDE3 activity is required for insulin/insulin-like growth factor-1 stimulation of Xenopus oocyte meiotic resumption. Here, we investigated the cAMP-dependent protein kinase B (PKB)/Akt regulation of PDE3A and its impact on oocyte maturation. Cell-free incubation of recombinant mouse PDE3A with PKB/Akt or cAMP-dependent protein kinase A catalytic subunits leads to phosphorylation of the PDE3A protein. Coexpression of PDE3A with constitutively activated PKB/Akt (Myr-Akt) increases PDE activity as well as its phosphorylation state. Injection of pde3a mRNA potentiates insulin-dependent maturation of Xenopus oocytes and rescues the phenotype of pde3(-/-) mouse oocytes. This effect is greatly decreased by mutation of any of the PDE3A serines 290-292 to alanine in both Xenopus and mouse. Microinjection of myr-Akt in mouse oocytes causes in vitro meiotic maturation and this effect requires PDE3A. Collectively, these data indicate that activation of PDE3A by PKB/Akt-mediated phosphorylation plays a role in the control of PDE3A activity in mammalian oocytes.

An improved hybrid unified power flow controller (IHUPFC) is developed in this paper to increase the utilization rate of transmission line and enhance the transmission capacity in extra-high voltage (EHV) and ultra-high voltage (UHV) grid. Based on introducing the existing power flow controllers, the advantages of IHUPFC in structure and performance are analyzed. The proposed IHUPFC is composed of an improved phase shift transformer (IPST) and a small capacity UPFC. The proposed IPST has simpler structure, smaller size and larger power flow control area than that of “SEN” transformer. The IHUPFC provides an independent, bidirectional and continuous active and reactive power flow control in the transmission line as UPFC does. The technology of IHUPFC is reliable and cost-effective. Simulation results were used to verify the practicability of IHUPFC.

Additive manufacturing of silicone parts using Direct Ink Writing is interesting for producing parts with complex geometries, especially for medical applications and soft robotics. Using commercially available off-the-shelf solutions, the process currently relies on the choice by the user of a standardized rigid nozzle prior to printing. The nozzle orifice dimensions must then respect a trade-off between resolution and control over manufacturing time: a small-diameter nozzle allows for higher printing precision, but at the cost of longer printing times. Furthermore, in the case of a non-Newtonian fluid such as silicone, the internal geometry of the nozzle channel directly affects the shape of the extruded bead. A solution based on a variable-geometry nozzle is presented to contribute to the development of active nozzles. It relies on a deformable body, actuated by nine independent actuators, permitting continuous variation of the shape and dimensions of the orifice during the printing process, and also independently of the internal geometry of the nozzle. The proposed solution enables the independent displacement of the orifice from the printer end-effector. The staged configuration of the nozzle also makes it possible to act on flow dynamics. The behavior of the nozzle is assessed in printing conditions, and the associated results show that the nozzle is capable of producing beads of variable diameter, reducing printing time. The displacement of the position of a printed bead, independently of the end-effector of the printing structure, is highlighted, and a direct influence on fluid dynamics at the nozzle output is observed. • A nozzle with active control of orifice size and overall shape is proposed. • Orifice size can vary from 0.32 to 1.11 mm, reducing a sample printing time by 50%. • The nozzle mobilities can be used in conjunction with the printing system motion. • The nozzle motions are shown to provide possible improvement of printing accuracy. • Using nozzle shape modification can help to control the material flow.