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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]

The pulmonary endothelium is a dynamic and metabolically active monolayer of endothelial cells. Dysfunction of the pulmonary endothelial barrier plays a crucial role in the acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), frequently observed in the context of viral pneumonia. Dysregulation of tight junction proteins can lead to the disruption of the endothelial barrier and subsequent leakage. Here, the highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) served as an ideal model for studying ALI and ARDS. The alveolar lavage fluid of pigs infected with HP-PRRSV, and the supernatant of HP-PRRSV infected pulmonary alveolar macrophages were respectively collected to treat the pulmonary microvascular endothelial cells (PMVECs) in Transwell culture system to explore the mechanism of pulmonary microvascular endothelial barrier leakage caused by viral infection. Cytokine screening, addition and blocking experiments revealed that proinflammatory cytokines IL-1β and TNF-α, secreted by HP-PRRSV-infected macrophages, disrupt the pulmonary microvascular endothelial barrier by downregulating claudin-8 and upregulating claudin-4 synergistically. Additionally, three transcription factors interleukin enhancer binding factor 2 (ILF2), general transcription factor III C subunit 2 (GTF3C2), and thyroid hormone receptor-associated protein 3 (THRAP3), were identified to accumulate in the nucleus of PMVECs, regulating the transcription of claudin-8 and claudin-4. Meanwhile, the upregulation of ssc-miR-185 was found to suppress claudin-8 expression via post-transcriptional inhibition. This study not only reveals the molecular mechanisms by which HP-PRRSV infection causes endothelial barrier leakage in acute lung injury, but also provides novel insights into the function and regulation of tight junctions in vascular homeostasis. [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]

Background: Next-generation sequencing (NGS) is maturely applied for gene fusion detection. Although tumor fusion burden (TFB) has been identified as an immune marker for cancer, the relationship between these fusions and the immunogenicity and molecular characteristics of gastric cancer (GC) patients remains unclear. GCs have different clinical significance depending on their subtypes, and thus, this study aimed to investigate the characteristics and clinical relevance of TFB in non-Epstein–Barr-virus-positive (EBV+) GC with microsatellite stability (MSS). Methods: A total of 319 GC patients from The Cancer Genome Atlas stomach adenocarcinoma (TCGA-STAD) and a cohort of 45-case from ENA (PRJEB25780) were included. The cohort characteristics and distribution of TFB among the patients were analyzed. Additionally, the correlations of TFB with mutation characteristics, pathway differences, relative abundance of immune cells, and prognosis were examined in the TCGA-STAD cohort of MSS and non-EBV (+) patients. Results: We observed that in the MSS and non-EBV (+) cohort, the TFB-low group exhibited significantly lower gene mutation frequency, gene copy number, loss of heterozygosity score, and tumor mutation burden than in the TFB-high group. Additionally, the TFB-low group exhibited a higher abundance of immune cells. Furthermore, the immune gene signatures were significantly upregulated in the TFB-low group, 2-year disease-specific survival was markedly increased in the TFB-low group compared with to the TFB-high group. The rates of TFB-low cases were significantly higher TFB-than high cases in durable clinical benefit (DCB) and response groups with pembrolizumab treatment. Low TFB may serve as a predictor of GC prognosis, and the TFB-low group exhibits higher immunogenicity. Conclusion: In conclusion, this study reveals that the TFB-based classification of GC patient may be instructive for individualized immunotherapy regimens. [ABSTRACT FROM AUTHOR]

In this paper, the periodic traveling wave solution for a reaction–diffusion SIR epidemic model with demography and time-periodic coefficients is investigated. Because the traveling wave system of non-autonomous reaction–diffusion model is a partial differential equation system, some traditional methods using only the theory of ordinary differential equations are no longer applicable. To overcome these difficulties, the traditional methods are extended and improved, and some new techniques are introduced. The research results show that the existence and nonexistence of traveling wave solutions are determined by the basic reproduction number R 0 and the minimal wave speed c ∗ . Specifically, when R 0 > 1 and the wave speed c > c ∗ the existence of periodic traveling wave solutions is proved by means of auxiliary system, upper–lower solutions, fixed-point theorems and some limit arguments. Otherwise, when R 0 < 1 , for any wave speed c > 0 the nonexistence of periodic traveling wave solutions is proved. Lastly, the numerical examples are carried out to verify the theoretical results. [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]

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]

Flexible sensors based on double-network (DN) hydrogels have become a research hotspot for wearable sensors. However, developing hydrogel-based strain sensors with high tensile properties, sensitivity, and wide detection range remains a great challenge. Herein, a novel highly stretchable, sensitive, and durable strain sensor based on MXene-enhanced polyacrylamide/carboxymethyl cellulose double-network hydrogel (PCM) was prepared, where PAM served as the rigid backbone, while CMC mainly acted as a flexible sub-network structure. MXene was utilized to enhance the mechanical properties of the hydrogel via tight hydrogen bonds between its surface functional groups and the chains of PAM and CMC, while also being applied to build a conductive path in the system. As a result, the prepared hydrogel-based strain sensor featured a wide detection range (0–500%), quick response time (120 ms for loading time and 190 ms for unloading time), high sensitivity (a gauge factor of 16.33), great toughness, and excellent stability. These advantages enable the prepared sensor to be used in dynamically monitoring human movements, such as joint bending, and performing handwriting recognition. This work provides potential development, research and application of double-network flexible hydrogel in wearable materials. [Display omitted] • CMC was used to construct a lamellar structure in the PAM backbone. • MXene nanosheets were anchored to the CMC chains to avoid stacking. • The PCM-0.2 hydrogels showed a fracture strain up to 530%. • PAM-0.2 hydrogels exhibited a high sensitivity of 16.33. • PAM-0.2 hydrogels possessed a wide operation window of 0–500%. [ABSTRACT FROM AUTHOR]

[Display omitted] A low crystalline 1T-MoS 2 @S-doped carbon (MoS 2 @SC) composite was successfully synthesized via a facile hydrothermal process. The composite is comprised by few-layer 1T-MoS 2 nanosheets covered by an amorphous carbon layer with an expanded interlayer d-spacing of 1.01 nm. This structure is conducive to the fast transport of lithium-ions and volume accommodation during the charge–discharge process when the composite is applied as an anode material for LIBs. Additionally, the high conductivity and layered structure of 1T-MoS 2 also facilitate fast of ion/electron transport, contributing to the improvement of the electrochemical properties. Therefore, this material demonstrated a high rate performance and excellent cycling stability, with the capacities of 847 and 622 mA h g−1 achieved at the current densities of 0.2 A g−1 and 2 A g−1, respectively. Even at a larger current density of 2 A g−1, MoS 2 @SC delivered a high reversible capacity of 659 mA h g−1 with an average capacity loss of 0.006% per cycle after 500 cycles. [ABSTRACT FROM AUTHOR]

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]

The three lowest energy conformations of the title compound have been investigated using quantum chemical calculations and the lowest energy conformer has been observed using pure rotational spectroscopy. The lowest energy conformer possesses C 2 symmetry, a helical CF 2 backbone, with the hydrogens nearly eclipsing one another when looking down the long axis of the molecule. The technique of Fourier transform microwave spectroscopy in conjunction with quantum chemical calculations is demonstrated as a complimentary method to X-ray diffraction for structural determinations of small oligomers for which the location of hydrogen atoms may be important. [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]

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]

Porcine reproductive and respiratory syndrome virus (PRRSV) is economically important and characterized by its extensive variation. The codon usage patterns and their influence on viral evolution and host adaptation among different PRRSV strains remain largely unknown. Here, the codon usage of ORF5 genes from lineages 1, 3, 5, and 8, and MLV strains of type 2 PRRSV in China was analyzed. A compositional property analysis of ORF5 genes revealed that nucleotide C is most frequently used at the third position of codons, accompanied by rich GC3s. The effective number of codon (ENC) and codon pair bias (CPB) values indicate that all ORF5 genes have low codon bias and the differences in CPB scores among four lineages are almost not significant. When compared with host codon usage patterns, lineage 1 strains show higher CAI and SiD values, with a high similarity to pig, which might relate to its predominant epidemic propensity in the field. The CAI, RCDI, and SiD values of ORF5 genes from different passages of MLV JXA1R indicate no relation between attenuation and CPB or codon adaptation decrease during serial passage on non-host cells. These findings provide a novel way of understanding the PRRSV's evolution, related to viral survival, host adaptation, and virulence. [ABSTRACT FROM AUTHOR]

This paper studies the traveling waves in a nonlocal dispersal SIR epidemic model with nonlinear incidence and distributed latent delay. It is found that the traveling waves connecting the disease-free equilibrium with endemic equilibrium are determined by the basic reproduction number R 0 and the minimal wave speed c ∗ . When R 0 > 1 and c > c ∗ , the existence of traveling waves is established by using the upper-lower solutions, auxiliary system, constructing the solution map, and then the fixed point theorem, limiting argument, diagonal extraction method, and Lyapunov functions. When R 0 > 1 and 0 < c < c ∗ , the nonexistence result is also obtained by using the reduction to absurdity and the theory of asymptotic spreading. [ABSTRACT FROM AUTHOR]

The loss of open-circuit voltage is a major obstacle for approaching the theoretical value of the power conversion efficiency in hybrid perovskite solar cells. In this study, a feasible and effective strategy for modifying the interface between the perovskite and the mesoporous TiO 2 layer is proposed and implemented for the first time using 2-methylimidazole as a coating layer. As a result, the open-circuit voltage in the perovskite solar cells is significantly improved by 80 mV. The electronic impedance spectroscopy and photoluminescence spectroscopy results demonstrate that the modification of 2-methylimidazole as an interfacial insulating layer suppresses the electron transfer back from the anode electrode to the perovskite active layer, thereby inhibiting the recombination of the carriers at the interfaces, which results in an enhancement of the open-circuit voltage in the device. The cell modified with 2-methylimidazole shows increases in the open-circuit voltage from 1.05 to 1.13 V and in the power conversion efficiency from 17.48% to 19.45%. The optimal device with an area of 1 cm2 also exhibits an impressive efficiency of 16.38%. Image 1 • 2-methylimidazole was used for modifying the interface of the PSCs. • The best efficiency of 19.45% was achieved in the optimal PSCs. • 2-methylimidazole inhibited the interfacial carrier's recombination in PSCs. [ABSTRACT FROM AUTHOR]

In the development of the modern electronics industry, the high mechanical performance, the green, and high-performance electromagnetic interference (EMI) shielding materials need to urgently be developed. Herein, polythiophene/Wood (PEDOT/wood) was fabricated through in situ polymerizing thiophene in the delignified paulownia wood. The results indicated that PEDOT were evenly distributed on the carbohydrates framework of the wood, endowing the composite with a highly electrical conductivity of 112.8 S m−1 and a superior electromagnetic shielding effectiveness of 46.2 dB at 2 mm thickness. The normalized SE (EMI SE/thickness) of the composite calculated as 213 dB/cm. Meanwhile, a high compressive strength and tensile strength of the prepared PEDOT/wood composite were tested as 50.9 MPa and 67.8 MPa, respectively. Such a high conductivity, strong mechanical properties and renewable PEDOT/wood suggests it as a potential candidate for the application in electromagnetic interference shielding and paves a new way for the biomass-based electromagnetic shielding materials. [Display omitted] • The conductive wood was prepared by in suit polymerization of polythiophene. • The PEDOT/wood exhibits high mechanical strength and electromagnetic shielding. • The PEDOT loading was enhanced by pre-impergnation of wood with Fe3+. • The electromagnetic wave shielding was dominated by absorption loss. [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]

Background: Porcine reproductive and respiratory syndrome virus (PRRSV) is an economically important pathogen, characterized by its genetic and antigenic variation. The PRRSV vaccine is widely used, however, the unsatisfied heterologic protection and the risk of reverse virulence raise the requirement to find some new anti-PRRSV strategies for disease control. Tylvalosin tartrate is used to inhibit PRRSV in the field non-specifically, however, the mechanism is still less known. Methods: The antiviral effects of Tylvalosin tartrates from three producers were evaluated in a cell inoculation model. Their safety and efficacy concentrations, and effecting stage during PRRSV infection were analyzed. And, the Tylvalosin tartrates regulated genes and pathways which are potentially related to the anti-viral effect were further explored by using transcriptomics analysis. Last, the transcription level of six anti-virus-related DEGs was selected to confirm by qPCR, and the expression level of HMOX1, a reported anti-PRRSV gene, was proved by western blot. Results: The safety concentrations of Tylvalosin tartrates from three different producers were 40 µg/mL (Tyl A, Tyl B, and Tyl C) in MARC-145 cells and 20 µg/mL (Tyl A) or 40 µg/mL (Tyl B and Tyl C) in primary pulmonary alveolar macrophages (PAMs) respectively. Tylvalosin tartrate can inhibit PRRSV proliferation in a dose-dependent manner, causing more than 90% proliferation reduction at 40 µg/mL. But it shows no virucidal effect, and only achieves the antiviral effect via long-term action on the cells during the PRRSV proliferation. Furthermore, GO terms and KEGG pathway analysis was carried out based on the RNA sequencing and transcriptomic data. It was found that the Tylvalosin tartrates can regulate the signal transduction, proteolysis, and oxidation-reduction process, as well as some pathways such as protein digestion and absorption, PI3K-Akt signaling, FoxO signaling, and Ferroptosis pathways, which might relate to PRRSV proliferation or host innate immune response, but further studies still need to confirm it. Among them, six antivirus-related genes HMOX1, ATF3, FTH1, FTL, NR4A1, and CDKN1A were identified to be regulated by Tylvalosin tartrate, and the increased expression level of HMOX1 was further confirmed by western blot. Conclusions: Tylvalosin tartrate can inhibit PRRSV proliferation in vitro in a dose-dependent manner. The identified DEGs and pathways in transcriptomic data will provide valuable clues for further exploring the host cell restriction factors or anti-PRRSV target. [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]