In this paper, we analyze downlink non-orthogonal multiple access (NOMA) networks with limited feedback. Our goal is to derive appropriate transmission rates for rate adaptation and minimize outage ...probability of minimum rate for the constant-rate data service, based on distributed channel feedback information from receivers. We propose an efficient quantizer with variable-length encoding that approaches the best performance of the case where perfect channel state information is available everywhere. We prove that in the typical application with two receivers, the losses in the minimum rate and outage probability decay at least exponentially with the minimum feedback rate. We analyze the diversity gain and provide a sufficient condition for the quantizer to achieve the maximum diversity order. For NOMA with K receivers where K > 2, we solve the minimum rate maximization problem within an accuracy of ϵ in time complexity of O (K log 1/ϵ), and then, we apply the previously proposed quantizers for K = 2 to the case of K > 2. Numerical simulations are presented to demonstrate the efficiency of our proposed quantizers and the accuracy of the analytical results.
This article examines Li Qingzhao’s much-debated remarriage case. Rumor had it that the preeminent female Ci lyric writer once remarried to a corrupt minor official Zhang Ruzhou after her husband’s ...death. However, by closely studying Li’s biographical records and evidence unearthed by Qing textual researchers, we argue that Qingzhao was attacked primarily because of her satirical literary criticism; she was simply ill-tolerated by a male-dominant society.
Metabolism of Amino Acids in Cancer Wei, Zhen; Liu, Xiaoyi; Cheng, Chunming ...
Frontiers in cell and developmental biology,
01/2021, Letnik:
8
Journal Article
Recenzirano
Odprti dostop
Metabolic reprogramming has been widely recognized as a hallmark of malignancy. The uptake and metabolism of amino acids are aberrantly upregulated in many cancers that display addiction to ...particular amino acids. Amino acids facilitate the survival and proliferation of cancer cells under genotoxic, oxidative, and nutritional stress. Thus, targeting amino acid metabolism is becoming a potential therapeutic strategy for cancer patients. In this review, we will systematically summarize the recent progress of amino acid metabolism in malignancy and discuss their interconnection with mammalian target of rapamycin complex 1 (mTORC1) signaling, epigenetic modification, tumor growth and immunity, and ferroptosis. Finally, we will highlight the potential therapeutic applications.
Studies on behavioral oscillations demonstrate that visual sensitivity fluctuates over time and visual processing varies periodically, mirroring neural oscillations at the same frequencies. Do these ...behavioral oscillations reflect fixed and relatively automatic sensory sampling, or top-down processes such as attention or predictive coding? To disentangle these theories, the current study used a dual-target rapid serial visual presentation paradigm, where participants indicated the gender of a face target embedded in streams of distractors presented at 30 Hz. On critical trials, two identical targets were presented with varied stimulus onset asynchrony from 200 to 833 ms. The target was either familiar or unfamiliar faces, divided into different blocks. We found a 4.6 Hz phase-coherent fluctuation in gender discrimination performance across both trial types, consistent with previous reports. In addition, however, we found an effect at the alpha frequency, with behavioral oscillations in the familiar blocks characterized by a faster high-alpha peak than for the unfamiliar face blocks. These results are consistent with the combination of both a relatively stable modulation in the theta band and faster modulation of the alpha oscillations. Therefore, the overall pattern of perceptual sampling in visual perception may depend, at least in part, on task demands. PROTOCOL REGISTRATION: The stage 1 protocol for this Registered Report was accepted in principle on 16/08/2022. The protocol, as accepted by the journal, can be found at: https://doi.org/10.17605/OSF.IO/A98UF .
Abstract
We aimed to provide a laboratory basis for differential diagnosis of COVID-19 and severe fever with thrombocytopenia syndrome (SFTS). Clinical data were collected from 32 COVID-19 patients ...(2019-nCoV group), 31 SFTS patients (SFTS group) and 30 healthy controls (control group). For each group of hospitalized patients, a retrospective analysis was performed on specific indices, including cytokines, T-lymphocyte subsets, routine blood parameters, C-reactive protein (CRP) and procalcitonin (PCT), and receiver operating characteristic (ROC) curves for the indices revealed the differences among groups. Compared with the 2019-nCoV group, the SFTS group had a significantly and greatly decreased counts of WBC, absolute lymphocyte, PLT and absolute CD4
+
T lymphocyte (
P
< 0.05); the IL-6, TNF-α, D-D and PCT levels of the SFTS group were higher than those of the 2019-nCoV group (
P
< 0.05). Compared with those of the SFTS group, the CRP and FIB levels of the 2019-nCoV group were greatly increased (
P
< 0.05). The ROC curves showed that area under the curves (AUCs) for FIB, PLT and TNF-α were greater than 0.85, demonstrating high diagnostic value. At the initial stage of SARS-CoV-2 or SFTS virus infection, PLT, FIB and TNF-α have definitive clinical value for the early and differential diagnosis of these two infections.
•Cobalt ferrite NPs induce oxidative stress in developing Zebrafish.•Cobalt ferrite NPs induce developmental malformations in developing Zebrafish.•Cobalt ferrite NPs induce apoptosis in developing ...Zebrafish.•Cobalt ferrite NPs shows interferences with assay components.
The broad spectrum applications of CoFe2O4 NPs have attracted much interest in medicine, environment and industry, resulting in exceedingly higher exposures to humans and environmental systems in succeeding days. Their health effects and potential biological impacts need to be determined for risk assessment. Zebrafish (Danio rerio) embryos were exposed to environmentally relevant doses of nano-CoFe2O4 (mean diameter of 40nm) with a concentration range of 10–500μM for 96h. Acute toxic end points were evaluated by survival rate, malformation, hatching delay, heart dysfunction and tail flexure of larvae. Dose and time dependent developmental toxicity with severe cardiac edema, down regulation of metabolism, hatching delay and tail/spinal cord flexure and apoptosis was observed. The biochemical changes were evaluated by ROS, Catalase (CAT), Lipid peroxidation (LPO), Acid phophatase (AP) and Glutatione s- transferase (GST). An Agglomeration of NPs and dissolution of ions induces severe mechanical damage to membranes and oxidative stress. Severe apoptosis of cells in the head, heart and tail region with inhibition of catalase confirms ROS induced acute toxicity with increasing concentration. Increased activity of GST and AP at lower concentrations of CoFe2O4 NPs demonstrates the severe oxidative stress. Circular dichroism (CD) spectra indicated the weak interactions of NPs with BSA and slight changes in α-helix structure. In addition, CoFe2O4 NPs at lower concentrations do not show any considerable interference with assay components and analytical instruments. The results are possible elucidation of pathways of toxicity induced by these particles, as well as contributing in defining the protocols for risk assessment of these nanoparticles.
A
bstract
We consider four-dimensional Euclidean gravity in a finite cavity. Dirichlet conditions do not yield a well-posed elliptic system, and Anderson has suggested boundary conditions that do. ...Here we point out that there exists a one-parameter family of boundary conditions, parameterized by a constant
p
, where a suitably Weyl rescaled boundary metric is fixed, and all give a well-posed elliptic system. Anderson and Dirichlet boundary conditions can be seen as the limits
p
→ 0 and ∞ of these. Focussing on static Euclidean solutions, we derive a thermodynamic first law. Restricting to a spherical spatial boundary, the infillings are flat space or the Schwarzschild solution, and have similar thermodynamics to the Dirichlet case. We consider smooth Euclidean fluctuations about the flat space saddle; for
p
> 1/6 the spectrum of the Lichnerowicz operator is stable — its eigenvalues have positive real part. Thus we may regard large
p
as a regularization of the ill-posed Dirichlet boundary conditions. However for
p
< 1/6 there are unstable modes, even in the spherically symmetric and static sector. We then turn to Lorentzian signature. For
p
< 1/6 we may understand this spherical Euclidean instability as being paired with a Lorentzian instability associated with the dynamics of the boundary itself. However, a mystery emerges when we consider perturbations that break spherical symmetry. Here we find a plethora of dynamically unstable modes even for
p
> 1/6, contrasting starkly with the Euclidean stability we found. Thus we seemingly obtain a system with stable thermodynamics, but unstable dynamics, calling into question the standard assumption of smoothness that we have implemented when discussing the Euclidean theory.
A
bstract
Due to the conformal factor problem, the definition of the Euclidean gravitational path integral requires a non-trivial choice of contour. The present work examines a generalization of a ...recently proposed rule-of-thumb 1 for selecting this contour at quadratic order about a saddle. The original proposal depended on the choice of an indefinite-signature metric on the space of perturbations, which was taken to be a DeWitt metric with parameter
α
= – 1. This choice was made to match previous results, but was otherwise admittedly
ad hoc
. To begin to investigate the physics associated with the choice of such a metric, we now explore contours defined using analogous prescriptions for
α
≠ – 1. We study such contours for Euclidean gravity linearized about AdS-Schwarzschild black holes in reflecting cavities with thermal (canonical ensemble) boundary conditions, and we compare path-integral stability of the associated saddles with thermodynamic stability of the classical spacetimes. While the contour generally depends on the choice of DeWitt parameter
α
, the precise agreement between these two notions of stability found at
α
= – 1 continues to hold over the finite interval (– 2, – 2/
d
), where
d
is the dimension of the bulk spacetime. This agreement manifestly fails for
α
> – 2/
d
when the DeWitt metric becomes positive definite. However, we also find dramatic failures for
α
< – 2 that correlate with breakdowns of the de Donder-like gauge condition defined by
α
, and at which the relevant fluctuation operator fails to be diagonalizable. This provides criteria that may be useful in predicting metrics on the space of perturbations that give physically-useful contours in more general settings. Along the way, we also identify an interesting error in 1, though we show this error to be harmless.
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