Dietary restriction of the essential amino acid, methionine, has been shown to induce unique metabolic protection. The peripheral benefits of methionine restriction (MR) are well established and include improvements in metabolic, energy, inflammatory, and lifespan parameters in preclinical models. These benefits all occur despite MR increasing energy intake, making MR an attractive dietary intervention for the prevention or reversal of many metabolic and chronic conditions. New and emerging evidence suggests that MR also benefits the brain and promotes cognitive health. Despite widespread interest in MR over the past few decades, many findings are limited in scope, and gaps remain in our understanding of its comprehensive effects on the brain and cognition. This review details the current literature investigating the impact of MR on cognition in various mouse models, highlights some of the key mechanisms responsible for its cognitive benefits, and identifies gaps that should be addressed in MR research moving forward. Overall findings indicate that in animal models, MR is associated with protection against obesity-, age-, and Alzheimer’s disease-induced impairments in learning and memory that depend on different brain regions, including the prefrontal cortex, amygdala, and hippocampus. These benefits are likely mediated by increases in fibroblast growth factor 21, alterations in methionine metabolism pathways, reductions in neuroinflammation and central oxidative stress, and potentially alterations in the gut microbiome, mitochondrial function, and synaptic plasticity.
more »
« less
This content will become publicly available on March 5, 2027
Non-traditional granular magnetoresistive devices: a short review
This review is focused on non-traditional granular magnetoresistive (MR) sensors. It discusses the underlying physical mechanisms, material configurations, fabrication strategies, and MR device performance evolution over the past two decades.
more »
« less
- PAR ID:
- 10681338
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Nanoscale
- Volume:
- 18
- Issue:
- 9
- ISSN:
- 2040-3364
- Page Range / eLocation ID:
- 4568 to 4580
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Yap, Alpha (Ed.)The mouse ocular lens is an excellent vertebrate model for epithelial cell hexagonal packing during tissue morphogenesis. As lens epithelial cells differentiate into fiber cells, the epithelial cells rearrange into hexagonally packed meridional row (MR) cells that further differentiate to form fiber cells. We previously reported that the nonmuscle myosin IIA (NMIIA)-E1841K mutation, which alters NMIIA bipolar filament assembly, significantly disrupts MR cell hexagonal packing. Immunofluorescence microscopy of MR cells demonstrates increased enrichment of NMIIA, N-cadherin, and vinculin at anterior–posterior (AP)-oriented sides of control MR cells, but equal distributions on all sides of mutant MR cells. Furthermore, F-actin is uniformly distributed around all edges of control MR cells but reduced at the AP-oriented edges of mutant MR cells. Using Bayesian Mechanical Inference, we discovered that MR cells in control lenses exhibit anisotropic junctional tension, in which relative tension is more concentrated at the AP-oriented edges. In contrast, MR cells in mutant lenses show isotropic junctional tension on all sides. We conclude that the NMIIA-E1841K mutation results in altered F-actin, NMIIA, N-cadherin, and vinculin distributions, disrupting the anisotropic orientational pattern of mechanical forces within the tissue, leading to disordered cell packing during mouse lens epithelial cell differentiation.more » « less
-
Abstract CRISPR activation is a powerful tool to upregulate a vast array of genes in many different contexts. However, there are few dynamic CRISPR transcriptional programs, which limit its usage in the creation of living biosensors, self-regulating microbial factories, or conditional therapeutics. Here, we address this limitation by embedding a molecular switch directly into a guide RNA to create a combined sensor–actuator called a metabolite-responsive scaffold RNA (MR-scRNA). We demonstrate the regulatory potential for MR-scRNAs by conditionally activating genes in three different kingdoms of life. We create MR-scRNAs responsive to two distinct metabolites, theophylline and tryptophan, by swapping the molecular switch used. MR-scRNAs respond quickly in a dose-dependent manner specifically to their target metabolite and enhance biochemical production when used as a dynamic regulator of pathway enzyme expression. The broad functionality and ease of design of the MR-scRNAs offer a promising tool for dynamic cellular regulation.more » « less
-
Hall effect generates a global quadrupole Hall magnetic field, which plays a crucial role in facilitating fast magnetic reconnection (MR). Tearing instability often arises in MR due to the increasing magnetic shear during the thinning of the current sheet, triggering multiple fast local spontaneous MRs. A critical question that naturally emerges is how these local spontaneous MRs interact with the global Hall magnetic field and affect the reconnection energy release processes. Using a 2.5D particle-in-cell simulation, we investigate this problem in an MR with a Harris current sheet under the guide field-free condition. Our results show that the global MR evolves through two distinct phases: an initial laminar phase marked by a slow magnetic field dissipation, followed by a phase dominated by spontaneous MRs that significantly accelerate the magnetic energy release by driving multiple local spontaneous MRs. We reveal that the Hall magnetic fields produced by the local spontaneous MRs also exhibit quadrupole structures, which reinforce or weaken the global Hall magnetic field locally. The local enhanced Hall field is found to be associated with a faster spontaneous MR with a rate up to 0.3, which exceeds the laminar MR rate upper-limit 0.2, suggesting that the Hall field interactions may be able to break the bottleneck of the onset of fast MR.more » « less
-
Abstract Recent immersive mixed reality (MR) and virtual reality (VR) displays enable users to use their hands to interact with both veridical and virtual environments simultaneously. Therefore, it becomes important to understand the performance of human hand-reaching movement in MR. Studies have shown that different virtual environment visualization modalities can affect point-to-point reaching performance using a stylus, but it is not yet known if these effects translate to direct human-hand interactions in mixed reality. This paper focuses on evaluating human point-to-point motor performance in MR and VR for both finger-pointing and cup-placement tasks. Six performance measures relevant to haptic interface design were measured for both tasks under several different visualization conditions (“MR with indicator,” “MR without indicator,” and “VR”) to determine what factors contribute to hand-reaching performance. A key finding was evidence of a trade-off between reaching “motion confidence” measures (indicated by throughput, number of corrective movements, and peak velocity) and “accuracy” measures (indicated by end-point error and initial movement error). Specifically, we observed that participants tended to be more confident in the “MR without Indicator” condition for finger-pointing tasks. These results contribute critical knowledge to inform the design of VR/MR interfaces based on the application's user performance requirements.more » « less
An official website of the United States government
