A Capacitive 3-Axis MEMS Accelerometer for Medipost: A Portable System Dedicated to Monitoring Imbalance Disorders

The constant development and miniaturization of MEMS sensors invariably provides new possibilities for their use in health-related and medical applications. The application of MEMS devices in posturographic systems allows faster diagnosis and significantly facilitates the work of medical staff. MEMS accelerometers constitute a vital part of such systems, particularly those intended for monitoring patients with imbalance disorders. The correct design of such sensors is crucial for gathering data about patient movement and ensuring the good overall performance of the entire system. This paper presents the design and measurements of a three-axis accelerometer dedicated for use in a device which tracks patient movement. Its main focus is the characterization of the sensor, comparing different designs and evaluating the impact of the packaging and readout circuit integration on sensor operation. Extensive testing and measurements confirm that the designed accelerometer works correctly and allows identifying the best design in terms of sensitivity/stability. Moreover, the response of the proposed sensor as a function of the applied acceleration demonstrates very good linearity only if the readout circuit is integrated in the same package as the MEMS sensor.

Mature parvalbumin interneuron function in prefrontal cortex requires activity during a postnatal sensitive period

Sensitive periods in which experience-driven changes in activity persistently shape circuit function are well-described in sensory cortex. Whether comparable periods govern the development of associative cortical areas, like the prefrontal cortex, remains unclear. Here, we focus on the role of activity in the maturation and circuit integration of prefrontal parvalbumin-expressing interneurons, as these cells play an essential role in sensory cortical maturation and develop in lockstep with overall prefrontal circuit function. We found that transiently decreasing prefrontal parvalbumin activity during peripubertal and adolescent development results in persistent impairments in adult functional connectivity, in vivo network function and set-shifting behavior that can be rescued by targeted activation of these interneurons in the adult animal. In contrast, comparable adult inhibition had no lasting effects. These findings identify an activity-dependent sensitive period for prefrontal parvalbumin maturation and highlight how abnormal parvalbumin activity early in life can persistently alter adult circuit function and behavior.

Insights of device structure, process and material design for organic thin-film transistor towards functional circuit integration

With tremendous efforts from material chemistry and processing techniques of organic semiconductors (OSCs), organic thin-film transistors (OTFTs) with much higher mobilities than that of amorphous silicon (a-Si) TFTs have been...

High-k Boron Nitride Sheets/Polyimide Hybrid Dielectric Layers for the Fabrication of Flexible Organic Transistors on Commercial Graphite Paper

Organic transistors are crucial components in future flexible electronics due to their excellent properties and ease of circuit integration. Previously, we demonstrated that flexible organic (polyimide) thermal transistors could be prepared using commercial graphite paper as the substrate. These materials exhibited excellent temperature sensitivity, linearity and recoverability due to the intrinsically high thermal conductivity of graphite. In this study, boron nitride (BN) sheets/polyimide hybrid dielectric layers were synthesized for the fabrication of flexible organic transistors using a commercial graphite paper. Under test, the results showed that the introduction of BN sheets was beneficial in improving the mobility and transistor characteristics of the device, as well as enhancing the overall stability. The as-fabricated transistors virtually exhibited no hysteresis at all BN contents.

Cryogenic Materials and Circuit Integration for Quantum Computers

Over the last decade, quantum computing has experienced significant changes and captured worldwide attention. In particular, superconducting qubits have become the leading candidates for scalable quantum computers, and a number of cryogenic materials have scientifically demonstrated their potential uses in constructing qubit chips. However, because of insufficient coherence time, establishing a robust and scalable quantum platform is still a long-term goal. Another consideration is the control circuits essential to initializing, operating and measuring the qubits. To keep noise low, control circuits in close proximity to the qubits require superior reliability in the cryogenic environment. The realization of the quantum advantage demands qubits with appropriate circuitry designs to maintain long coherence times and entanglement. In this work, we briefly summarize the current status of cryogenic materials for qubits and discuss typical cryogenic circuitry designs and integration techniques for qubit chips. In the end, we provide an assessment of the prospects of quantum computers and some other promising cryogenic materials.

Temporally-Divergent Regulatory Mechanisms Govern Neuronal Development and Diversification in the Neocortex

Mammalian neocortical neurons span one of the most diverse cell type spectra of any tissue. The regulatory strategies that neurons use during progressive development and maturation remain unclear. We present an integrated single-cell epigenomic and transcriptional analysis of individual classes of neurons from both mouse and marmoset neocortex, sampled during both early postmitotic stages of identity acquisition and later stages of neuronal plasticity and circuit integration. We find that in both species, the regulatory strategies controlling these early and late stages diverge: early postmitotic neurons use molecular regulatory programs with broader tissue distribution and greater evolutionary conservation, while programs active during later neuronal maturation implement more brain- and neuron-specific mechanisms showing greater evolutionary divergence. The data uncovers a temporally-regulated shift in regulatory choices, likely reflecting unique evolutionary constraints on distinct events of neuronal development in the neocortex.