Publications by authors named "Byungwoo Kang"

Addressing and mitigating decoherence sources plays an essential role in the development of a scalable quantum computing system, which requires low gate errors to be consistently maintained throughout the circuit execution. While nuclear spin-free materials, such as isotopically purified silicon, exhibit intrinsically promising coherence properties for electron spin qubits, the omnipresent charge noise, when converted to magnetic noise under a strong magnetic field gradient, often hinders stable qubit operation within a time frame comparable to the data acquisition time. Here, we demonstrate both open- and closed-loop suppression techniques for the transduced noise in silicon spin qubits, resulting in a more than two-fold (ten-fold) improvement of the inhomogeneous coherence time (Rabi oscillation quality) that leads to a single-qubit gate fidelity of over 99.

View Article and Find Full Text PDF

Alzheimer's disease (AD) poses a major societal challenge, yet no definitive cure exists. Noninvasive brain stimulation methods, such as transcranial magnetic stimulation and transcranial direct current stimulation, have shown promise in alleviating cognitive symptoms associated with neurodegenerative disorders. This study investigated the effects of 40 Hz vibrotactile stimulation on AD-related cellular responses using SH-SY5Y neuroblastoma cells, primary human brain pericytes, and BV2 microglia.

View Article and Find Full Text PDF

Neural activity underlying short-term memory is maintained by interconnected networks of brain regions. It remains unknown how brain regions interact to maintain persistent activity while exhibiting robustness to corrupt information in parts of the network. We simultaneously measured activity in large neuronal populations across mouse frontal hemispheres to probe interactions between brain regions.

View Article and Find Full Text PDF
Article Synopsis
  • - Most research on neural representations has concentrated on single brain areas, but there's increasing evidence that cognitive variables are represented in parallel across multiple regions of the brain.
  • - Experiments show that the way these brain regions interact can vary widely between different pairs, impacting how they coordinate neural representations and influence behavior.
  • - Advances in recording technology allow for simultaneous observation of multiple brain areas, facilitating better understanding of their interactions, as demonstrated in a study of rodents performing a delayed response task.
View Article and Find Full Text PDF

Purpose: The purpose of this study was to determine whether ginseng berry extract improves blood circulation by regulating vasodilator expression in exposed to tumor necrosis factor alpha (TNF-α)-exposed endothelial cells and muscle cells.

Methods: Nitric oxide (NO) and cGMP levels in human umbilical vein endothelial cells (HUVECs) and A7r5 cells exposed to ginseng berry extract were investigated. Based on the in vitro results, healthy participants were treated with ginseng berry extract for 4 weeks and then a non-invasive vascular screening device was used to confirm the improvement of blood circulation.

View Article and Find Full Text PDF

Because of the spherical shape of the human eye, the anterior segments of the eye, particularly the cornea and the lens, create high levels of refraction and reflection of ultrasound which negatively affect the performance of linear and convex arrays. To minimize the ultrasound energy loss, a 15-MHz concave array transducer was designed, fabricated, and characterized; its footprint is able to mesh well with the shape of the cornea. The concave array has a curvature with a radius of 15 mm and 128 elements with a 1.

View Article and Find Full Text PDF

Members of the Eph family have been implicated in the formation of cell-cell boundaries, cell movement, and positioning during development in the context of cancer progression. De-regulation of this signaling system is linked to the promotion of more aggressive and metastatic tumor phenotypes in a large variety of human cancers, including breast, lung, and prostate cancer, melanoma, and leukemia. Thus, it is interesting to consider the case of cancer progression where de-regulation of the Eph/ephrin signaling system results in invasion and metastasis.

View Article and Find Full Text PDF