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This paper investigates a nonlocal dispersal epidemic model under the multiple nonlocal distributed delays and nonlinear incidence effects. First, the minimal wave speed c ∗ and the basic reproduction number R 0 are defined, which determine the existence of traveling wave solutions. Second, with the help of the upper and lower solutions, Schauder's fixed point theorem, and limiting techniques, the traveling waves satisfying some asymptotic boundary conditions are discussed. Specifically, when ℛ 0 > 1 , for every speed c > c ∗ there exists a traveling wave solution satisfying the boundary conditions, and there is no such traveling wave solution for any 0 < c < c ∗ when ℛ 0 > 1 or c > 0 when ℛ 0 < 1. Finally, we analyze the effects of nonlocal time delay on the minimum wave speed. [ABSTRACT FROM AUTHOR]

Considering the importance of time delay phenomenon in disease transmission and the interdependence of time delay and spatial location, a reaction-diffusion SIR epidemic model with nonlocal time delay (or time-space time delay) is proposed and the travelling wave solutions are discussed. Specifically, we define the basic reproduction number $ \mathcal {R}_0 $ R0 and the critical wave speed $ c^* $ c∗. For every wave speed $ c\geq c^* $ c≥c∗, the existence of travelling wave solutions is studied by using the upper–lower solutions, the fixed-point theorem and some limit techniques when $ \mathcal {R}_0 \gt 1 $ R0>1. The nonexistence of travelling waves when $ \mathcal {R}_0 \gt 1 $ R0>1 for any $ 0 \lt c \lt c^* $ 0c>0 is also proved. Finally, the influence of time-delay on disease propagation, especially the critical wave speed, is discussed through analysis and simulations. [ABSTRACT FROM AUTHOR]

Methoxy poly(ethylene glycol)-block-poly(L-lactide) (MPEG-b-PLLA) has a wide range of applications in pharmaceuticals and biology, and its structure and morphology have been thoroughly studied. In the experiment, we synthesized MPEG-b-PLLA with different block lengths using the principle of ring-opening polymerization by controlling the amount of lactic acid added. The thermodynamic properties of copolymers and the crystallization properties of blends were studied separately. The crystallization kinetics of PDLA/MPEG-b-PLA and PLLA/MPEG-b-PLA composite films were studied using differential scanning calorimetry (DSC). The results indicate that the crystallization kinetics of composite films are closely related to the amount of block addition. The crystallinity of the sample first increases and then decreases with an increase in MPEG-b-PLLA content. These results were also confirmed in polarized optical microscope (POM) and wide-angle X-ray diffraction (WAXD) tests. When 3% MPEG-b-PLLA was added to the PDLA matrix, the blend exhibited the strongest crystallization performance. [ABSTRACT FROM AUTHOR]

BiFeO3/La0.7Sr0.3MnO3 (BFO/LSMO) epitaxial heterostructures were successfully synthesized by pulsed laser deposition on (001)-oriented SrTiO3 single-crystal substrates with Au top electrodes. Stable bipolar resistive switching characteristics regulated by ferroelectric polarization reversal was observed in the Au/BFO/LSMO heterostructures. The conduction mechanism was revealed to follow the Schottky emission model, and the Schottky barriers in high-resistance and low-resistance states were estimated based on temperature-dependent current–voltage curves. Further, the observed memristive behavior was interpreted via the modulation effect on the depletion region width and the Schottky barrier height caused by ferroelectric polarization reversal, combining with the oxygen vacancies migration near the BFO/LSMO interface. [ABSTRACT FROM AUTHOR]

This paper is concerned with the existence and nonexistence of traveling waves of a virus infection model with humoral immunity, cell‐to‐cell transmission, and general nonlinear incidence. Our results show that the existence of traveling wave solutions is determined not only by the basic reproduction number R0$$ {\mathcal{R}}_0 $$ of virus infection and the antibody response reproduction number R1$$ {\mathcal{R}}_1 $$ but also by the critical wave speed c∗$$ {c}^{\ast } $$. More precisely, we obtain the existence of traveling wave solution connecting infection‐free equilibrium and antibody‐free infection equilibrium for R0>1,R1<1$$ {\mathcal{R}}_0>1,{\mathcal{R}}_1<1 $$, and c>c∗$$ c>{c}^{\ast } $$ and connecting infection‐free equilibrium and antibody‐present infection equilibrium for R0>1,R1>1$$ {\mathcal{R}}_0>1,{\mathcal{R}}_1>1 $$, and c>c∗$$ c>{c}^{\ast } $$. The existence of traveling wave solution connecting infection‐free equilibrium and antibody‐present infection equilibrium is discussed. Some numerical simulations are carried out to illustrate our analytical results. [ABSTRACT FROM AUTHOR]

Over the past three decades, its excellent biodegradability and biocompatibility have enabled poly(lactide) (PLA) to be extensively explored as a replacement for oil-based thermoplastics in biomedical and industrial applications. However, PLA homopolymers have "facilitative" limitations such as low mechanical properties, low processing temperatures, slow recrystallization, and insufficient crystallinity, which have usually hindered commercial PLA in industrial and biomedical applications. The formation of stereo-complexation between enantiomeric poly(L -lactide) (PLLA) and poly(D -lactide) (PDLA) chains offers an effective approach to PLA-based engineering materials with improved properties. In this review, we have understandably summarized recent progress in improving the SC crystallization of PLA-based plastics into two aspects, i.e., enantiomeric PLA homopolymers, and enantiomeric PLA-based copolymers. One important point to be noted is that much emphasis is focused on improving SC crystallization by enhancing interactions in the enantiomeric PLA-based copolymers. There is an insightful discussion about the effect of enhanced SC crystallization as well as intermolecular interactions between PLLA and PDLA chains in various stereocomplexable systems. Most importantly, this review starts with the basic understanding of SC crystallization and further elaborates on the rational mechanism of enhanced SC crystallization to provide a broad idea for broadening the road toward PLA-based materials. [ABSTRACT FROM AUTHOR]

The branched poly(ethylene glycol)-poly(lactic acid)-glucose (PEG-b-PLLA-g-glucose) copolymers were synthesized by using CDI as the bonding agent. There is a significant inhibition between PEG segments and PLLA segments in PEG-b-PLLA-g-glucose copolymers. When the weight fraction of PLLA is low, the PEG segment as the diluting agent increases the flexibility and chain diffusion ability of PEG-b-PLLA-g-glucose copolymers, and also improves the formation of the α-form for the extensive melting process of the PLLA matrix. The initial decomposition temperature (T5%) of PEG-b-PLLA-g-glucose copolymers was significantly reduced, due to the enhanced transesterification of the PLLA segment at both ends under the low melting PEG to promote the thermal degradation of copolymers. When the PLLA content reaches a certain level, due to the PEG segment as a plasticizer to enhance the interaction between PLLA chains, T5% is slightly improved during the heating process. With an increase of the branched PEG-b-PLLA grafted segments, the morphological structure and surface morphology of PEG-b-PLLA-g-glucose copolymers changed from the spherical micelles and irregular surfaces to tightly fused circular lamellas and corrugated dense surfaces, respectively. This work provides a potential theoretical basis for broadening PLLA application by the crystallization behaviors and morphologies of the branched PEG-b-PLLA copolymers with various architectures and different compositions. [ABSTRACT FROM AUTHOR]

Snow pears are an important and widespread agricultural product that can relieve respiratory symptoms, constipation, and alcoholism. Lignin content (LC) has a direct and negative role on the fruit texture and taste of snow pears. Here, we studied the effect on the near‐infrared (NIR) spectroscopy determination of the LC in snow pears due to the position at which spectral measurements were obtained. NIR diffuse reflection spectra were collected from nine measurement positions on each sample by a portable NIR spectrometer. Partial least squares regression (PLSR) was used to develop spectrum compensation models of the LC for three local spectrum models, an average spectrum model, and a global spectrum model. The results indicated that the prediction accuracy of the LC was affected by the spectral measurement position. Compared with the local spectrum models and the global spectrum model, the average spectrum model had good prediction results. Next, synergy interval partial least squares, bootstrapping soft shrinkage, competitive adaptive reweighted sampling, genetic algorithm, and an improved variable stability and frequency analysis algorithm (VSFAA) method were used to select the most effective variables to build the PLSR model. The average spectrum calibration model established using the 10 effective variables selected by VSFAA reduced the influence of the variation of the spectral measurement position for LC prediction and achieved more promising results, with the correlation coefficient of calibration and prediction of 0.842 and 0.824, respectively. The root mean square error of cross‐validation and prediction were 0.736 and 0.694, respectively. The overall results showed that the average spectrum model based on the nine spectral measurement positions reduced the sensitivity to the variation of spectral measurement position for predicting the LC and combined the VSFAA variable selection algorithm to improve the accuracy and provide a robust model for prediction of LC in snow pears. Compared with the local spectrum position models and the global spectrum position model, the average spectrum position model combining the nine measurement positions (three stem‐calyx longitudes intersected three latitudes (stem, equator, calyx)) produced good prediction results and reduced the sensitivity to the variation of the spectral measurement position. The effective wavelengths (SNV‐VSFAA‐PLSR)‐average spectrum position model achieved good results, reducing the influence of the variation of the spectral measurement position for LC prediction, and the effective wavelengths selected from the average spectrum position model were helpful for offsetting the influence of the variation of spectral measurement position on the PLSR models based on the spectrum from the equatorial positions alone. [ABSTRACT FROM AUTHOR]

The aim of this paper is to study the periodic traveling wave solutions in a nonautonomous reaction-diffusion susceptible-infected-removed epidemic model with general nonlinear incidence and time-periodic environment. The basic reproduction number R 0 and the critical wave speed c* are defined. By the fixed-point theorem and upper–lower solutions, the sufficient conditions for the existence of traveling waves satisfying some asymptotic boundary conditions are deduced, and the nonexistence of periodic traveling waves is also obtained. Numerical simulations are carried out to support the theoretical results. [ABSTRACT FROM AUTHOR]

In order to widen voltage gain of bidirectional on-board charger to meet requirements of electric vehicle with different voltage levels, a novel bidirectional five-level multimode CLLC resonant converter is proposed by combining the CLLC resonant tank module (RTM) with the five-level cascaded neutral-point clamp active bridge which is composed of two three-level neutral-point clamp (3L-NPC) bridge arms. Furthermore, the converter can, respectively, establish three voltage gain modes of high, medium, and low to effectively widen voltage gain adjustment capabilities through the fixed-frequency plus phase-shift hybrid modulation independently adopted in each 3L-NPC bridge arm, while soft-switching is realized by phase control between resonant current and input voltage of RTM. Meanwhile, the key parameters of RTM would be symmetrically designed to make bidirectional power transmission characteristics, which become consistent based on soft-switching and monotonic voltage gain control. Finally, according to the simulation platform and experimental prototype, it can be shown that the practical voltage gain is close to the theoretical design gain and converter has good dynamic performances after realizing soft-switching in each mode. [ABSTRACT FROM AUTHOR]

The porcine reproductive and respiratory syndrome virus (PRRSV), especially the highly pathogenic strains, can cause serious acute lung injury (ALI), characterized by extensive hemorrhage, inflammatory cells and serous fluid infiltration in the lung vascular system. Meanwhile, the pulmonary microvascular endothelial cells (PMVECs) are essential for forming the air–blood barrier and keeping the water–salt balance to prevent leakage of circulating nutrients, solutes, and fluid into the underlying tissues. As well, they tightly regulate the influx of immune cells. To determine the possible relationship between the PMVECs' function changes and lung vascular permeability during PRRSV infection, the PMVECs were co-cultured with HP-PRRSV-inoculated primary pulmonary alveolar macrophages (PAMs) in transwell model, and then the RNA sequencing (RNA-seq) and comprehensive bioinformatics analysis were carried out to characterize the dynamic transcriptome landscapes of PMVECs. In total, 16,489 annotated genes were identified, with 275 upregulated and 270 downregulated differentially expressed genes (DEGs) were characterized at both 18 and 24 h post PRRSV inoculation. The GO terms and KEGG pathways analysis indicated that the immune response, metabolic pathways, cell death, cytokine–cytokine receptor interaction, viral responses, and apoptotic process are significantly regulated upon co-culture with PRRSV-infected PAMs. Moreover, according to the TERR and dextran flux assay results, dysregulation of TJ proteins, including CLDN1, CLDN4, CLDN8, and OCLN, is further confirmed to correlate with the increased permeability of PMVECs. These transcriptome profiles and DEGs will provide valuable clues for further exploring the roles of PMVECs in PRRSV-induced ALI in the future. [ABSTRACT FROM AUTHOR]

We have analyzed and compared two different multiuser detection receiver structures that are appropriate for code-division multiple access (CDMA) systems with multiple antennas in frequency-selective multipath channels. Distributed decorrelation detection (where signal decorrelation is performed at each receiving antenna) and centralized decorrelation detection (where decorrelation is performed once collectively) are compared. We show that they provide the same performance in additive Gaussian channels. Centralized decorrelation detection provides better performance in general frequency-selective multipath fading channels. Therefore, the hardware cost, complexity, and processing at the receiver can be optimized using centralized decorrelation detection. We employ decorrelation detection to demonstrate our results, although the work can be easily extended to other linear multiuser detection configurations. Index Terms--Antenna array, code-division multiple access (CDMA), decorrelation, multipath, multiuser detection.

In this paper, for a class of nonlocal dispersal SIR epidemic models with nonlinear incidence, we study the existence of traveling waves connecting the disease-free equilibrium with endemic equilibrium. We obtain that the existence of traveling waves depends on the minimal wave speed c ∗ and basic reproduction number R 0 . That is, if R 0 > 1 and c > c ∗ then the model has a traveling wave connecting the disease-free equilibrium with endemic equilibrium. Otherwise, if R 0 > 1 and 0 < c < c ∗ , then there does not exist the traveling wave connecting the disease-free equilibrium with endemic equilibrium. The numerical simulations verify the theoretical results. Our results improve and generalize some known results. [ABSTRACT FROM AUTHOR]

[Display omitted] • An organic molybdenum complex is firstly used to synthesize MoO 2 /NC nanocomposite. • The synthetic route is easy, green, and economical with a yeild of nearly 100% • The nanoparticles with ultra-small size facilitates the conversion reaction. • N -doped carbon increase the structural integrity and electrical conductivity. • MoO 2 /NC exhibits an excellent electrochemical performance for Li-ion storage. MoO 2 is a promising anode material for lithium-ion batteries, however, the lithiation of bulk MoO 2 is usually limited to addition-type reaction at room temperature, and the conversion reaction is hindered because of the sluggish kinetics. Herein, a nanocomposite of MoO 2 embedded in nitrogen-doped carbon (MoO 2 /NC) is synthesized through the in situ thermolysis of an organic molybdenum complex MoO 2 (acac)(phen) (acac = acetylacetone, phen = 1,10-Phenanthroline). Owing to the fact that [MoO 2 ]2+ can be strongly chelated by phen, the molybdenum source in the MoO 2 (acac)(phen) precursor is highly dispersed, leading to the formation of ultra-small MoO 2 nanoparticles in the nanocomposite, which can facilitate the conversion reaction. Moreover, the NC matrix can guarantee a high electrical conductivity and effectively accommodate the volume changes triggered by the conversion reaction. Consequently, the MoO 2 /NC nanocomposite exhibits outstanding electrochemical properties, including large reversible capacity of 950 mA h g−1 at 0.1 A g−1, high-rate capability of 605 mA h g−1 at 2 A g−1, and excellent cycling stability over 500 cycles as an anode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

This paper investigates the traveling wave in a nonlocal dispersal susceptible-infected-removed epidemic model with general nonlinear incidence and nonlocal delayed effects. It is shown that the existence and nonexistence of nontrivial traveling waves are fully determined by the basic reproduction number R 0 and critical wave speed c*. When R 0 > 1 and c > c*, the existence of traveling waves is obtained by means of an auxiliary system, the methods of upper-lower solutions, Schauder's fixed point theorem, and some limiting techniques. When R 0 > 1 and 0 < c < c*, the nonexistence of traveling waves is established by the reduction to absurdity and the theory of asymptotic spreading. [ABSTRACT FROM AUTHOR]

Background: The accurate detection of cancer-associated venous thromboembolism (VTE) can avoid unnecessary diagnostic imaging or laboratory tests.Objective: We sought to determine clinical and cancer-related risk factors of VTE that can be used as predictors for oncology patients presenting to the emergency department (ED) with suspected VTE.Methods: We retrospectively analyzed all consecutive patients who presented with suspicion of VTE to The University of Texas MD Anderson Cancer Center ED between January 1, 2009, and January 1, 2013. Logistic regression models were used to identify risk factors that were associated with VTE. The ability of these factors to predict VTE was externally validated using a second cohort of patients who presented to King Hussein Cancer Center ED between January 1, 2009, and January 1, 2016.Results: Cancer-related covariates associated with the occurrence of VTE were high-risk cancer type (odds ratio [OR] 3.64 [95% confidence interval {CI} 2.37-5.60], p < 0.001), presentation within 6 months of the cancer diagnosis (OR 1.92 [95% CI 1.62-2.28], p < 0.001), active cancer (OR 1.35 [95% CI 1.10-1.65], p = 0.003), advanced stage (OR 1.40 [95% CI 1.01-1.94], p = 0.044), and the presence of brain metastasis (OR 1.73 [95% CI 1.32-2.27], p < 0.001). When combined, these factors along with other clinical factors showed high prediction performance for VTE in the external validation cohort.Conclusions: Cancer risk group, presentation within 6 months of cancer diagnosis, active and advanced cancer, and the presence of brain metastases along with other related clinical factors can be used to predict VTE in patients with cancer presenting to the ED. [ABSTRACT FROM AUTHOR]

Magnetic induction field (MIF) of the magnetite particles with five Johnson solid shapes was analyzed using the finite-element method. A new method is proposed to calculate the MIF of irregular magnetite particles by studying their magnetic flux density, and the results show that sphericity is a key factor affecting the MIF of a regular-shaped particle. Moreover, the calculation value of the MIF using particle volume radius ($r$) is more accurate with the higher sphericity. In addition, the relative position is another important factor affecting the accuracy of MIF calculation. The further the distance from the particle center, the more accurate is the MIF. More specifically, when the distance is $4r$ , the average value of the relative difference drops to less than 5.0% with the sphericity of 0.91, 0.92, and 0.93, respectively. Therefore, we suggest that it is feasible to use a sphere MIF instead of an irregular particle MIF to simulate the interaction and motion of massive magnetite particles. [ABSTRACT FROM AUTHOR]

Background: Docetaxel, a lipophilic drug, is indicated for castration-resistant metastatic prostate cancer. Most men with such disease would have had androgen-deprivation therapy, which decreases muscle and increases body fat. Obesity and body composition changes may influence the outcomes of docetaxel therapy. Methods: We conducted a retrospective review of 333 patients with metastatic prostate cancer treated with docetaxel at a comprehensive cancer center between October 7, 2004 and December 31, 2012. Body composition parameters were measured based on the areas of muscle and adipose tissues in the visceral and subcutaneous compartments on CT images at L3-4 levels. Dose calculations, toxicity and adverse reaction profiles, and overall survival were analyzed. Results: Obese patients were younger at the diagnosis of prostate cancer and had a shorter duration from diagnosis to docetaxel therapy. Analysis of body composition found that a high visceral fat-to-subcutaneous fat area ratio (VSR) was associated with poor prognosis but a high visceral fat-to-muscle area ratio (VMR) and high body mass index were associated with increased duration from starting docetaxel to death, allowing such men to catch up with patients with normal body mass index in overall survival from cancer diagnosis to death. Cox proportional hazard regression showed that age ≥65 years, high VSR, abnormal serum alkaline phosphatase, and >10% reduction of initial dosage were significant predictors of shorter time between starting docetaxel and death, and that high VMR, obesity, and weekly regimens were significant predictors of longer survival after docetaxel. Conclusion: Obese and overweight patients may benefit more from weekly docetaxel regimens using the reference dosage of 35 mg/m2 without empirical dosage reduction. [ABSTRACT FROM AUTHOR]

A toxin producing phytoplankton-zooplankton model with inhibitory exponential substrate and time delay has been formulated and analyzed. Since the liberation of toxic substances by phytoplankton species is not an instantaneous process but is mediated by some time lag required for maturity of the species and the zooplankton mortality due to the toxic phytoplankton bloom occurs after some time laps of the bloom of toxic phytoplankton, we induced a discrete time delay to both of the consume response function and distribution of toxic substance term. Furthermore, based on the fact that the predation rate decreases at large toxic-phytoplankton density, the system is modelled via a Tissiet type functional response. We study the dynamical behaviour and investigate the conditions to guarantee the coexistence of two species. Analytical methods and numerical simulations are used to obtain information about the qualitative behaviour of the models. [ABSTRACT FROM AUTHOR]