Among the experimental realization of fault-tolerant topological circuits are interconnecting nanowires with minimal disorder. Out-of-plane indium antimonide (InSb) nanowire networks formed by merging are potential candidates. Yet, their growth requires a foreign material stem usually made of InP-InAs.
View Article and Find Full Text PDFFormation and retrieval of remote contextual memory depends on cortical engram neurons that are defined during learning. Manipulation of astrocytic G and G associated G-protein coupled receptor (GPCR) signaling has been shown to affect memory processing, but little is known about the role of cortical astrocytic G-GPCR signaling in remote memory acquisition and the functioning of cortical engram neurons. We assessed this by chemogenetic manipulation of astrocytes in the medial prefrontal cortex (mPFC) of male mice, during either encoding or consolidation of a contextual fear memory, while simultaneously labeling cortical engram neurons.
View Article and Find Full Text PDFSilicon is indisputably the most advanced material for scalable electronics, but it is a poor choice as a light source for photonic applications, due to its indirect band gap. The recently developed hexagonal SiGe semiconductor features a direct bandgap at least for x > 0.65, and the realization of quantum heterostructures would unlock new opportunities for advanced optoelectronic devices based on the SiGe system.
View Article and Find Full Text PDFTopological crystalline insulators (TCIs) are interesting for their topological surface states, which hold great promise for scattering-free transport channels and fault-tolerant quantum computing. A promising TCI is SnTe. However, Sn-vacancies form in SnTe, causing a high hole density, hindering topological transport from the surface being measured.
View Article and Find Full Text PDFAlzheimer's disease (AD) is a progressive neurodegenerative disease and the most common cause of dementia, characterized by deposition of extracellular amyloid-beta (Aβ) aggregates and intraneuronal hyperphosphorylated Tau. Many AD risk genes, identified in genome-wide association studies (GWAS), are expressed in microglia, the innate immune cells of the central nervous system. Specific subtypes of microglia emerged in relation to AD pathology, such as disease-associated microglia (DAMs), which increased in number with age in amyloid mouse models and in human AD cases.
View Article and Find Full Text PDFMonoclinic vanadium dioxide (VO (M)) is a promising material for various applications ranging from sensing to signature management and smart windows. Most applications rely on its reversible structural phase transition to rutile VO (VO (R)), which is accompanied by a metal-to-insulator transition. Bottom-up hydrothermal synthesis has proven to yield high quality monoclinic VO but requires toxic and highly reactive reducing agents that cannot be used outside of a research lab.
View Article and Find Full Text PDFMonolithic integration of silicon-based electronics and photonics could open the door toward many opportunities including on-chip optical data communication and large-scale application of light-based sensing devices in healthcare and automotive; by some, it is considered the Holy Grail of silicon photonics. The monolithic integration is, however, severely hampered by the inability of Si to efficiently emit light. Recently, important progress has been made by the demonstration of efficient light emission from direct-bandgap hexagonal SiGe (hex-SiGe) alloy nanowires.
View Article and Find Full Text PDFIntroduction: Early-life stress (ES) increases the risk for Alzheimer's disease (AD). We and others have shown that ES aggravates amyloid-beta (Aβ) pathology and promotes cognitive dysfunction in APP/PS1 mice, but underlying mechanisms remain unclear.
Methods: We studied how ES affects the hippocampal synaptic proteome in wild-type (WT) and APP/PS1 mice at early and late pathological stages, and validated hits using electron microscopy and immunofluorescence.
Two-dimensional MoS is a promising material for applications, including electronics and electrocatalysis. However, scalable methods capable of depositing MoS at low temperatures are scarce. Herein, we present a toolbox of advanced plasma-enhanced atomic layer deposition (ALD) processes, producing wafer-scale polycrystalline MoS films of accurately controlled thickness.
View Article and Find Full Text PDFThe continuous flow reverse water gas shift (rWGS) process was efficiently catalyzed by a plasmonic Au/TiO nanocatalyst using sunlight as sole and sustainable energy source. The influence of the catalyst bed thickness on the CO production rate was studied, and three different catalytic regimes were identified as direct plasmon catalysis (DPC), shielded plasmon catalysis (SPC) and unused plasmon catalysis (UPC). The CO : H ratio was optimized to 4 : 1 and a maximum CO production rate of 7420 mmol ⋅ m ⋅ h was achieved under mild reaction conditions (p=3.
View Article and Find Full Text PDFPotentially traumatic events (PTEs) are associated with a higher risk of mental health problems and a lack of emotional support. The extent to which pre- and/or post-trauma financial problems further increase this risk, while controlling for pre-trauma mental health problems and lack of support and compared to nonvictims, is largely unknown. To better understand this risk, data was extracted from four surveys of VICTIMS study using the Dutch population-based longitudinal LISS-panel.
View Article and Find Full Text PDFDesigner Receptors Exclusively Activated by Designer Drugs (DREADDs) have proven themselves as one of the key techniques of modern neuroscience, allowing for unprecedented access to cellular manipulations in living animals. With respect to astrocyte research, DREADDs have become a popular method to examine the functional aspects of astrocyte activity, particularly G-protein coupled receptor (GPCR)-mediated intracellular calcium (Ca) and cyclic adenosine monophosphate (cAMP) dynamics. With this method it has become possible to directly link the physiological aspects of astrocytic function to cognitive processes such as memory.
View Article and Find Full Text PDFLoss of function of the astrocyte membrane protein MLC1 is the primary genetic cause of the rare white matter disease Megalencephalic Leukoencephalopathy with subcortical Cysts (MLC), which is characterized by disrupted brain ion and water homeostasis. MLC1 is prominently present around fluid barriers in the brain, such as in astrocyte endfeet contacting blood vessels and in processes contacting the meninges. Whether the protein plays a role in other astrocyte domains is unknown.
View Article and Find Full Text PDFIntroduction: Astrocyte-synapse bi-directional communication is required for neuronal development and synaptic plasticity. Astrocytes structurally interact with synapses using their distal processes also known as leaflets or perisynaptic astrocytic processes (PAPs). We recently showed that these PAPs are retracted from hippocampal synapses, and involved in the consolidation of fear memory.
View Article and Find Full Text PDFBackground: The formation and retrieval of fear memories depends on orchestrated synaptic activity of neuronal ensembles within the hippocampus, and it is becoming increasingly evident that astrocytes residing in the environment of these synapses play a central role in shaping cellular memory representations. Astrocyte distal processes, known as leaflets, fine-tune synaptic activity by clearing neurotransmitters and limiting glutamate diffusion. However, how astroglial synaptic coverage contributes to mnemonic processing of fearful experiences remains largely unknown.
View Article and Find Full Text PDFIn many nano(opto)electronic devices, the roughness at surfaces and interfaces is of increasing importance, with roughness often contributing toward losses and defects, which can lead to device failure. Consequently, approaches that either limit roughness or smoothen surfaces are required to minimize surface roughness during fabrication. The atomic-scale processing techniques atomic layer deposition (ALD) and atomic layer etching (ALE) have experimentally been shown to smoothen surfaces, with the added benefit of offering uniform and conformal processing and precise thickness control.
View Article and Find Full Text PDFThe direct catalytic conversion of atmospheric CO to valuable chemicals is a promising solution to avert negative consequences of rising CO concentration. However, heterogeneous catalysts efficient at low partial pressures of CO still need to be developed. Here, we explore Co/CeO as a catalyst for the methanation of diluted CO streams.
View Article and Find Full Text PDFThe data currently described was generated within the EU/FP7 HeCaToS project (Hepatic and Cardiac Toxicity Systems modeling). The project aimed to develop an in silico prediction system to contribute to drug safety assessment for humans. For this purpose, multi-omics data of repeated dose toxicity were obtained for 10 hepatotoxic and 10 cardiotoxic compounds.
View Article and Find Full Text PDFJ Phys Chem C Nanomater Interfaces
November 2022
Preparation conditions have a vital effect on the structure of alumina-supported hydrodesulfurization (HDS) catalysts. To explore this effect, we prepared two NiMoS/AlO catalyst samples with the same target composition using different chemical sources and characterizing the oxidic NiMo precursors and sulfided and spent catalysts to understand the influence of catalyst structure on performance. The sample prepared from ammonium heptamolybdate and nickel nitrate (sample A) contains Mo in the oxidic precursor predominantly in tetrahedral coordination in the form of crystalline domains, which show low reducibility and strong metal-support interactions.
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