771,852 research outputs found
Anchored phosphatases modulate glucose homeostasis.
Endocrine release of insulin principally controls glucose homeostasis. Nutrient-induced exocytosis of insulin granules from pancreatic β-cells involves ion channels and mobilization of Ca(2+) and cyclic AMP (cAMP) signalling pathways. Whole-animal physiology, islet studies and live-β-cell imaging approaches reveal that ablation of the kinase/phosphatase anchoring protein AKAP150 impairs insulin secretion in mice. Loss of AKAP150 impacts L-type Ca(2+) currents, and attenuates cytoplasmic accumulation of Ca(2+) and cAMP in β-cells. Yet surprisingly AKAP150 null animals display improved glucose handling and heightened insulin sensitivity in skeletal muscle. More refined analyses of AKAP150 knock-in mice unable to anchor protein kinase A or protein phosphatase 2B uncover an unexpected observation that tethering of phosphatases to a seven-residue sequence of the anchoring protein is the predominant molecular event underlying these metabolic phenotypes. Thus anchored signalling events that facilitate insulin secretion and glucose homeostasis may be set by AKAP150 associated phosphatase activity
Pseudo noise code and data transmission method and apparatus
Pseudo noise ranging codes, having a predetermined chipping rate, and a pair of binary data sources, each having a bit rate no greater than one tenth the chipping rate, quadriphase, digitally modulate a suppressed carrier wave having a first frequency are examined. Two additional binary data sources, each having a bit rate that is not restricted by the chipping rate of the first carrier, quadriphase, digitally modulate a suppressed carrier wave having a second frequency. The first and second frequencies are only slightly displaced so that there is overlap in the frequency bands which modulate the two carriers. The two suppressed carrier waves are linearly combined and transmitted from a first station to a second station so that the amplitude of the transmitted first wave is controlled so as not to degrade the detectability of the second wave at the second station
Early redox activities modulate Xenopus tail regeneration.
Redox state sustained by reactive oxygen species (ROS) is crucial for regeneration; however, the interplay between oxygen (O2), ROS and hypoxia-inducible factors (HIF) remains elusive. Here we observe, using an optic-based probe (optrode), an elevated and steady O2 influx immediately upon amputation. The spatiotemporal O2 influx profile correlates with the regeneration of Xenopus laevis tadpole tails. Inhibition of ROS production but not ROS scavenging decreases O2 influx. Inhibition of HIF-1α impairs regeneration and stabilization of HIF-1α induces regeneration in the refractory period. In the regeneration bud, hypoxia correlates with O2 influx, ROS production, and HIF-1α stabilization that modulate regeneration. Further analyses reveal that heat shock protein 90 is a putative downstream target of HIF-1α while electric current reversal is a de facto downstream target of HIF-1α. Collectively, the results show a mechanism for regeneration via the orchestration of O2 influx, ROS production, and HIF-1α stabilization
Noninvasive brain stimulation techniques can modulate cognitive processing
Recent methods that allow a noninvasive modulation of brain activity are able to modulate human cognitive behavior. Among these methods are transcranial electric stimulation and transcranial magnetic stimulation that both come in multiple variants. A property of both types of brain stimulation is that they modulate brain activity and in turn modulate cognitive behavior. Here, we describe the methods with their assumed neural mechanisms for readers from the economic and social sciences and little prior knowledge of these techniques. Our emphasis is on available protocols and experimental parameters to choose from when designing a study. We also review a selection of recent studies that have successfully applied them in the respective field. We provide short pointers to limitations that need to be considered and refer to the relevant papers where appropriate
Commentary: Prestimulus theta oscillations and connectivity modulate pain perception
Pain experience includes the fine-grain integration of both attentive and automatic (bottom-up; Legrain et al., 2012), as well as affective and intentional (top-down; Buschman and Miller, 2007) processes. While the neural underpinnings of post-stimulus pain processing have been deeply explored (Hauck et al., 2008), the oscillatory brain activity preceding pain processing is less far investigated
How Does Folding Modulate Thermal Conductivity of Graphene
We study thermal transport in folded graphene nanoribbons using molecular
dynamics simulations and the non-equilibrium Green's function method. It is
found that the thermal conductivity of flat graphene nanoribbons can be
modulated by folding and changing interlayer couplings. The analysis of
transmission reveals that the reduction of thermal conductivity is due to
scattering of low frequency phonons by the folds. Our results suggest that
folding can be utilized in the modulation of thermal transport properties in
graphene and other two dimensional materials.Comment: published in Applied Physics Letters 201
Phenolic metabolites of anthocyanins modulate mechanisms of endothelial function
Anthocyanins are reported to have vascular bioactivity, however their mechanisms of action are largely unknown. Evidence suggests that anthocyanins modulate endothelial function, potentially by increasing nitric oxide (NO) synthesis, or enhancing NO bioavailability. This study compared the activity of cyanidin-3-glucoside, its degradation product protocatechuic acid, and phase II metabolite, vanillic acid. Production of NO and superoxide and expression of endothelial NO synthase (eNOS), NADPH oxidase (NOX), and heme oxygenase-1 (HO-1) were established in human vascular cell models. Nitric oxide levels were not modulated by the treatments, although eNOS was upregulated by cyanidin-3-glucoside, and superoxide production was decreased by both phenolic acids. Vanillic acid upregulated p22phox mRNA but did not alter NOX protein expression, although trends were observed for p47phox downregulation and HO-1 upregulation. Anthocyanin metabolites may therefore modulate vascular reactivity by inducing HO-1 and modulating NOX activity, resulting in reduced superoxide production and improved NO bioavailability
Scheme for preparation of W state via cavity QED
In this paper, we presented a physical scheme to generate the multi-cavity
maximally entangled W state via cavity QED. All the operations needed in this
scheme are to modulate the interaction time only once.Comment: 8 pages, 1 figur
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