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14-3-3ζ is overexpressed in several cancers, including esophageal squamous cell carcinoma (ESCC), and plays an important role in tumorigenesis. However, the mechanisms underlying its tumorigenesis remain unclear. Here we report that 14-3-3ζ was upregulated in ESCC tumors, compared with adjacent normal tissues; 14-3-3ζ levels were positively correlated with ESCC lymph node metastasis and recurrence. Overexpression of 14-3-3ζ promoted the tumor growth and invasion of ESCC in vitro and in vivo, whereas depletion of 14-3-3ζ suppressed these effects. Moreover, 14-3-3ζ reduces expression of genes mediating S1P/S1PR2 signaling, and this effect is mediated through activation of NF- κ B. Taken together, 14-3-3ζ contributes to ESCC tumorigenesis and progression through repressing S1PR2 signaling and may act as a new therapeutic target for ESCC.

Express Wavenet is an improved optical diffractive neural network. At each layer, it uses wavelet-like pattern to modulate the phase of optical waves. For input image with n2 pixels, express wavenet reduce parameter number from O(n2) to O(n). Only need one percent of the parameters, and the accuracy is still very high. In the MNIST dataset, it only needs 1229 parameters to get accuracy of 92%, while the standard optical network needs 125440 parameters. The random shift wavelets show the characteristics of optical network more vividly. Especially the vanishing gradient phenomenon in the training process. We present a modified expressway structure for this problem. Experiments verified the effect of random shift wavelet and expressway structure. Our work shows optical diffractive network would use much fewer parameters than other neural networks. The source codes are available at https://github.com/closest-git/ONNet., Comment: 5 pages,4 figures

Highlights • Patients in the experimental group received intravenous ribavirin versus supportive care only in the control group. • Ribavirin was not associated with reduced negative conversion time of SARS-CoV-2 PCR test compared with the control group. • Ribavirin did not reduce the mortality rate compared with the control group., The aim of this study was to compare ribavirin therapy versus supportive therapy only for patients with severe coronavirus disease 2019 (COVID-19). A total of 115 patients with laboratory-confirmed COVID-19 were retrospectively analysed. All patients received supportive care as well as regular laboratory and clinical monitoring. The 115 patients comprised 44 patients who received intravenous ribavirin (treatment group) and 71 who did not (control group). Baseline laboratory and clinical characteristics were similar between the two groups. The negative conversion time for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RT-PCR in the ribavirin group was 12.8 ± 4.1 days compared with 14.1 ± 3.5 days in the control group (P = 0.314). Moreover, 7/41 patients (17.1%) in the ribavirin group died compared with 17/69 (24.6%) in the control group (P = 0.475). Adverse effects were similar between the two groups. In conclusion, in patients with severe COVID-19, ribavirin therapy is not associated with improved negative conversion time for SARS-CoV-2 test and is not associated with an improved mortality rate. Further assessment in designed randomised controlled trials is recommended.

Background A few studies have revealed the clinical characteristics of hospitalized patients with COVID-19. However, predictive factors for the outcomes remain unclear. Objective Attempted to determine the predictive factors for the poor outcomes of patients with COVID-19. Study design This is a single-center, retrospective study. Clinical, laboratory, and treatment data were collected and analyzed from 111 hospitalized patients with laboratory-confirmed COVID-19 in Union Hospital. The gathered data of discharged and deteriorated patients were compared. Results Among these 111 patients, 93 patients were discharged and 18 patients were deteriorated. The lymphocyte count (0.56 G/L [0.47−0.63] vs 1.30 G/L [0.95−1.65]) was lower in the deteriorated group than those in the discharged group. The numbers of pulmonary lobe involved (5.00 [5.00–5.00] vs 4.00 [2.00−5.00]), serum C‐reactive protein (CRP, 79.52 mg/L [61.25−102.98] vs 7.93 mg/L [3.14−22.50]), IL-6 (35.72 pg/mL [9.24−85.19] vs 5.09 pg/mL [3.16−9.72]), and IL-10 (5.35 pg/mL [4.48−7.84] vs 3.97 pg/mL [3.34−4.79]) concentrations in deteriorated patients were elevated compared with discharged patients. Multivariate logistic regression analysis showed that male gender (OR, 24.8 [1.8−342.1]), comorbidity (OR, 52.6 [3.6−776.4]), lymphopenia (OR, 17.3 [1.1−261.8]), and elevated CRP (OR, 96.5 [4.6−2017.6]) were the independent risk factors for the poor prognosis in COVID-19 patients. Conclusions This finding would facilitate the early identification of high-risk COVID-19 patients.

Effects of mechanochemical degradation of the crosslinked and foamed ethylene-vinyl acetate copolymer (EVA) multicomponent and multiphase waste material in a solid state are studied with a HAAKE rheometer. The ruptures of chemical bonds in its net and stereo-structures are caused by external mechanical energy input by the Roller rotors of the HAAKE rheometer. A resource application method of the degradation product is obtained. The optimum mechanochemical degradation conditions are at 120–130 °C in a Roller rotor rotation speed range of 40–60 rpm for 24 min. Smaller polymer molecules have been generated so that the interfacial morphology, phase compatibility and plastic flow properties of the degradation product are all improved. The sol extracted from the degradation product is characterized with thermogravimetric analysis, gel permeation chromatography, nuclear magnetic resonance and Fourier transform infrared spectroscopy. Free radical reaction mechanisms are demonstrated in the degradation process. The degradation product partly replaces pure EVA in preparing the crosslinked and foamed material. Results show that the degradation product could be in resource application.

Multilevel fast multipole algorithm (MLFMA) is developed for solving elastic wave scattering by large three-dimensional (3D) objects. Since the governing set of boundary integral equations (BIE) for the problem includes both compressional and shear waves with different wave numbers in one medium, the double-tree structure for each medium is used in the MLFMA implementation. When both the object and surrounding media are elastic, four wave numbers in total and thus four FMA trees are involved. We employ Nystrom method to discretize the BIE and generate the corresponding matrix equation. The MLFMA is used to accelerate the solution process by reducing the complexity of matrix-vector product from O(N^2) to O(NlogN) in iterative solvers. The multiple-tree structure differs from the single-tree frame in electromagnetics (EM) and acoustics, and greatly complicates the MLFMA implementation due to the different definitions for well-separated groups in different FMA trees. Our Nystrom method has made use of the cancellation of leading terms in the series expansion of integral kernels to handle hyper singularities in near terms. This feature is kept in the MLFMA by seeking the common near patches in different FMA trees and treating the involved near terms synergistically. Due to the high cost of the multiple-tree structure, our numerical examples show that we can only solve the elastic wave scattering problems with 0.3-0.4 millions of unknowns on our Dell Precision 690 workstation using one core.

Nystrom method is developed to solve for boundary integral equations (BIE's) for elastic wave scattering by three-dimensional obstacles. To generate the matrix equation from a BIE, Nystrom method applies a quadrature rule to the integrations of smooth integrands over a discretized element directly and chooses the values of the unknown function at quadrature points as the system's unknowns to be solved. This leads to a simple procedure to form the off-diagonal entries of matrix by simply evaluating the integrands without numerical integrations. For the diagonal or near diagonal entries corresponding to the integrals over a singular or near-singular element where the kernels are singular or near singular, we develop a systematic singularity treatment technique, known as the local correction scheme, based on the linear approximation of elements. The scheme differs from the singularity regularization or subtraction technique used in the boundary element method (BEM). It applies the series expansion of scalar Green's function to the kernels and derives analytical solutions for the strongly singular integrals under the Cauchy principal value like (CPV-like) sense. Since the approach avoids the need for reformulating the BIE for singularity removal in BEM and solves for the Somigliana's equation directly, it is easy to implement and efficient in calculation. Numerical examples are used to demonstrate its robustness.

Polymer-supported phosphine ligand 3b derived from ferrocene was prepared, and applied in palladium-catalyzed Suzuki–Miyaura reactions. A range of aryl bromides can couple with phenylboronic acid to obtain corresponding biaryls in excellent yields. The recycling of the polymer-bound catalyst was tested without adding palladium.

A SiGe/Si Multiple Quantum Wells (MQWs) structure is proposed for highly sensitive photodetection. A large photoconductive gain is obtained because of the unique SiGe/Si band structure, i.e., a large band offset in the valence band, but a small band offset in the conduction band. Such a structure allows the trapping of photogenerated holes inside the valance band quantum wells. Alternatively, photogenerated electrons appear in shallow quantum wells and have relatively high mobility. These give rise to a large photoconductive gain. The calculated photoconductive gain for this structure exceeds 2 × 107. Experimental results confirmed a high gain of the structure.

Si-based normal incident mid-infrared photodetectors using Ge dots were investigated. P–I–P structures of boron-doped Ge dots embedded in the intrinsic region were grown using solid source molecular beam epitaxy. The dark current was strongly dependent on the doping level in Ge dot. The structure grown at 700 °C exhibited photoresponse peaking at 3.5 μm. FTIR measurements on identical structure showed an absorption band consistent with the photocurrent spectra. At lower temperatures, the response intensity decreased due to freeze-out of the holes. The devices also showed photovoltaic effect. The response increased with increasing bias.

The use of SiGe strained layers for BiCMOS technology has been prevailing in the market place for high-speed and high-frequency mixed mode applications. The advantages of using SiGe are due to its compatibility with mainstream Si CMOS processing. SiGe has also been gradually making its way to the mainstream strained layer CMOS as well. In this paper, we will discuss SiGe quantum structures, which have the unique properties due to their nanosize effects and the presence of strain. We will describe the growth of SiGe quantum dots on Si. First, for dot growth, issues such as the growth conditions and their effects on the dot morphology will be reviewed. We will focus on the dependence of growth temperature on the size and also show the mechanisms of uniform dot formation. The basic issues such as vertical correlation and dot morphology evolution will be addressed in relation to the critical thickness of Ge quantum dot superlattices. Both interband and intersubband photoluminescence properties of Ge quantum dot superlattices will be discussed as functions of dot size, excitation power, growth temperature, superlattice period, and Ge concentration. We will also discuss quantum dot pin photodetectors for 1.3–1.55 μm for integration with Si technology for communications applications. Potential light emission from dots will be described and the characteristics of fabricated LED devices will be reported. Likewise, we will show the results of intersubband properties of boron-doped and modulation-doped Ge quantum dot superlattices in reference to intersubband absorption as studied by FTIR. We will describe the quantum dot pip photodetectors for 3–5 and 8–12 μm applications.

Rheumatic fever (RF), a potential sequela of Streptococcus pyogenes pharyngitis, sometimes results in myocarditis and heart failure. Antibodies have been implicated in the pathogenesis of RF and anti-cardiac myosin antibody levels are elevated in RF patients. Since myocarditis is associated with altered cardiomyocyte calcium transients it was of interest to determine the direct effects of RF patient antibodies on calcium transients in cultured myocytes. RF patient polyclonal IgM treatment caused increased calcium retention by neonatal rat heart cells in vitro as determined with isotopically labeled calcium. Therefore, to further characterize this finding, calcium transients were evaluated by real time fluorescence spectroscopy and deconvolution imaging. RF patient polyclonal IgM produced increased calcium retention during the relaxation stage of the contraction cycle leading to a slowing of contraction rate, disorganized calcium transients, and eventual tetany. In contrast, calcium transient studies of cardiomyocytes following treatment with monoclonal anti-myosin antibodies revealed declining intracellular calcium levels, accompanied by disorganized transients and tetany. Treatment with both antibodies led to myocyte dysfunction and these novel findings suggest a role for antibodies in the pathogenesis of the myocarditis associated with rheumatic carditis.