Improved Reconstruction for Fourier-Sparse Signals

We revisit the classical problem of Fourier-sparse signal reconstruction -- a variant of the \emph{Set Query} problem -- which asks to efficiently reconstruct (a subset of) a $d$-dimensional Fourier-sparse signal ($\|\hat{x}(t)\|_0 \leq k$), from minimum \emph{noisy} samples of $x(t)$ in the time domain. We present a unified framework for this problem by developing a theory of sparse Fourier transforms (SFT) for frequencies lying on a \emph{lattice}, which can be viewed as a ``semi-continuous'' version of SFT in between discrete and continuous domains. Using this framework, we obtain the following results: $\bullet$ **Dimension-free Fourier sparse recovery** We present a sample-optimal discrete Fourier Set-Query algorithm with $O(k^{\omega+1})$ reconstruction time in one dimension, \emph{independent} of the signal's length ($n$) and $\ell_\infty$-norm. This complements the state-of-art algorithm of [Kapralov, STOC 2017], whose reconstruction time is $\tilde{O}(k \log^2 n \log R^*)$, where $R^* \approx \|\hat{x}\|_\infty$ is a signal-dependent parameter, and the algorithm is limited to low dimensions. By contrast, our algorithm works for arbitrary $d$ dimensions, mitigating the $\exp(d)$ blowup in decoding time to merely linear in $d$. A key component in our algorithm is fast spectral sparsification of the Fourier basis. $\bullet$ **High-accuracy Fourier interpolation** In one dimension, we design a poly-time $(3+ \sqrt{2} +\epsilon)$-approximation algorithm for continuous Fourier interpolation. This bypasses a barrier of all previous algorithms [Price and Song, FOCS 2015, Chen, Kane, Price and Song, FOCS 2016], which only achieve $c>100$ approximation for this basic problem. Our main contribution is a new analytic tool for hierarchical frequency decomposition based on \emph{noise cancellation}

Molybdenum disulfide nanoflowers mediated anti-inflammation macrophage modulation for spinal cord injury treatment

Spinal cord injury (SCI) can cause locomotor dysfunctions and sensory deficits. Evidence shows that functional nanodrugs can regulate macrophage polarization and promote anti-inflammatory cytokine expression, which is feasible in SCI immunotherapeutic treatments. Molybdenum disulfide (MoS2) nanomaterials have garnered great attention as potential carriers for therapeutic payload. Herein, we synthesize MoS2@PEG (MoS2 = molybdenum disulfide, PEG = poly (ethylene glycol)) nanoflowers as an effective carrier for loading etanercept (ET) to treat SCI. We characterize drug loading and release properties of MoS2@PEG in vitro and demonstrate that ET-loading MoS2@PEG obviously inhibits the expression of M1-related pro-inflammatory markers (TNF-α, CD86 and iNOS), while promoting M2-related anti-inflammatory markers (Agr1, CD206 and IL-10) levels. In vivo, the mouse model of SCI shows that long-circulating ET-MoS2@PEG nanodrugs can effectively extravasate into the injured spinal cord up to 96 h after SCI, and promote macrophages towards M2 type polarization. As a result, the ET-loading MoS2@PEG administration in mice can protect survival motor neurons, thus, reducing injured areas at central lesion sites, and significantly improving locomotor recovery. This study demonstrates the anti-inflammatory and neuroprotective activities of ET-MoS2@PEG and promising utility of MoS2 nanomaterial-mediated drug delivery

Gravitational-wave Detection With Matter-wave Interferometers Based On Standing Light Waves

We study the possibility of detecting gravitational-waves with matter-wave interferometers, where atom beams are split, deflected and recombined totally by standing light waves. Our calculation shows that the phase shift is dominated by terms proportional to the time derivative of the gravitational wave amplitude. Taking into account future improvements on current technologies, it is promising to build a matter-wave interferometer detector with desired sensitivity.Comment: 7 pages, 3 figures. To be published in General Relativity and Gravitatio

MEPE/OF45 protects cells from DNA damage induced killing via stabilizing CHK1

Matrix extracellular phosphoglycoprotein/osteoblast factor 45 (MEPE/OF45) was cloned in 2000 with functions related to bone metabolism. We identified MEPE/OF45 for the first time as a new co-factor of CHK1 in mammalian cells to protect cells from DNA damage induced killing. We demonstrate here that MEPE/OF45 directly interacts with CHK1. Knocking down MEPE/OF45 decreases CHK1 levels and sensitizes the cells to DNA damage inducers such as ionizing radiation (IR) or camptothicin (CPT)-induced killing. Over-expressing wild-type MEPE/OF45, but not the mutant MEPE/OF45 (depleted the key domain to interact with CHK1) increases CHK1 levels in the cells and increases the resistance of the cells to IR or CPT. MEPE/OF45, interacting with CHK1, increases CHK1 half-life and decreases CHK1 degradation through the ubiquitine-mediated pathway. In addition, the interaction of MEPE/OF45 with CHK1 decreases CHK1 levels in the ubiquitin E3 ligases (Cul1 and Cul4A) complex, which suggests that MEPE/OF45 competes with the ubiquitin E3 ligases binding to CHK1 and thus decreases CHK1 from ubiquitin-mediated proteolysis. These findings reveal an important role of MEPE/OF45 in protecting cells from DNA damage induced killing through stabilizing CHK1, which would provide MEPE/OF45 as a new target for sensitizing tumor cells to radiotherapy or chemotherapy

Polymorphisms of XRCC4 are involved in reduced colorectal cancer risk in Chinese schizophrenia patients

<p>Abstract</p> <p>Background</p> <p>Genetic factors related to the regulation of apoptosis in schizophrenia patients may be involved in a reduced vulnerability to cancer. XRCC4 is one of the potential candidate genes associated with schizophrenia which might induce colorectal cancer resistance.</p> <p>Methods</p> <p>To examine the genetic association between colorectal cancer and schizophrenia, we analyzed five SNPs (rs6452526, rs2662238, rs963248, rs35268, rs2386275) covering ~205.7 kb in the region of XRCC4.</p> <p>Results</p> <p>We observed that two of the five genetic polymorphisms showed statistically significant differences between 312 colorectal cancer subjects without schizophrenia and 270 schizophrenia subjects (rs6452536, p = 0.004, OR 0.61, 95% CI 0.44-0.86; rs35268, p = 0.028, OR 1.54, 95% CI 1.05-2.26). Moreover, the haplotype which combined all five markers was the most significant, giving a global <it>p </it>= 0.0005.</p> <p>Conclusions</p> <p>Our data firstly indicate that XRCC4 may be a potential protective gene towards schizophrenia, conferring reduced susceptibility to colorectal cancer in the Han Chinese population.</p

Simulation Parameter Selection and Steady Seepage Analysis of Binary Structure Slope

The selection of calculation parameters for slope excavation support design and the analysis of seepage stability is a significant challenge. This difficulty also hinders the development of slope support engineering. This study examined the right binary structure slope engineering of the K5 + 220&ndash;K5 + 770 section of the TJ1A mark of the Jiangkou-Weng&rsquo;an Highway in Guizhou province. In this study, we propose and use the deep displacement monitoring data and p value test method to check the simulation parameters. Furthermore, the superposition calculation method for steady-state seepage analysis of slope geotechnical structure is proposed. A comparative analysis of the displacement, strain, stress, and safety factor of the slope after the application of pore water pressure was carried out for three slope conditions. The analysis showed that steady-state seepage has a significant effect on the displacement of the slope during the completion of excavation. As a result, a continuous distribution of strain arises on the slope along the interface between the potential sliding surface and the rock&ndash;soil layer, and then forms a continuous sliding zone. Additionally, steady-state seepage has a significant effect on the position of the displacement distribution during the initial support of the slope, leading to a significant increase in the extreme value of the shear outlet displacement of the potential slip surface of the slope and in the extreme value of equivalent strain. Finally, steady-state seepage reduces the displacement and equivalent strain upon construction of the secondary slope support. The steady-state seepage has a limited effect on the stress concentration, but reduces the safety factor calculated using the strength reduction method, in all three stages of slope excavation and support. This study enriches the analysis methods for determining the stability of a dual-structure slope during the rainy season, and provides new ideas for the safety and control of slope support projects

Analysis of Compounds Dissolved in Nonpolar Solvents by Electrospray Ionization on Conductive Nanomaterials

Electrospray ionization mass spectrometry (ESI-MS) technique has limitations in analysis of compounds that are dissolved in nonpolar solvents. In this study, ambient ionization of compounds in solvents that are not "friendly" to electrospray ionization, such as n-hexane, is achieved by conductive nanomaterials spray ionization (CNMSI) on nanomaterial emitters, including carbon nanotubes paper and mesodendritic silver covered metal, which applies high voltages to emitters made of these materials without the assistance of polar solvents. Although the time intensity curves (TIC) commonly vary from 4.5% to 23.7% over analyses, protonated molecular ions were found to be the most abundant species, demonstrating good reproducibility of the technique in terms of ionized species. Higher mass spectrometric responses are observed in analyzing nonpolar systems than polar systems. 2-Methoxyacetophenone, 4-methylacetophenone, benzothiazole, quinolone, and cycloheptanone as low as 2 pg in n-hexane can be directly detected using the developed method. The developed technique expands the analysis capability of ESI-MS for direct, online analysis of nonpolar systems, such as low polarity extracts, normal phase liquid chromatography eluates, and synthetic mixtures

Role of Quantum Effect for Nano-confined Substance Ultrafast Flow

Many researchers, however, found that the flow of both liquid and gas through nanoscale pores is one to even seven orders of magnitude faster than that would be predicted from the classic Newton’s mechanic theories, such as the Hagen-Poiseuille equation, the Bernoulli’s principle, the Knudsen theory. Here, for the first time, we propose a possible explanation for the ultra-fast flow of substance through the nano-confined pores based on the Wave-Particle Dualism. Since the mass of the substance is a constant, the velocity of the substance in the nanopores is very important. The molecule behaves like a particle above the critical velocity, while could reduce its velocity to the critical value in the nanopores, which, then, behaves like the wave inducing the tunneling transfer. The critical velocities in 18 different study cases from the literatures have been calculated. The role of quantum effect for ultrafast flow could possibly provide new ideas for studying the nature of the physiological processes with the ion and molecule channels, which are the backbones for the biology, and possibly promote the development of new method for energy conversion, desalination of sea water and even for information systems. </p