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Nanoporous gold (NPG) is a promising catalytic material for the oxidation of CO and methanol applications. However, NPGs are prone to extensive macroscopic cracking that often decrease mechanic properties of NPGs and depresses their catalytic action. To produce crack-free NPG with an ultra-finer porosity in room temperature, the anionic surfactant sodium dodecyl sulfate (SDS) was added in electrochemical dealloying process. SDS has the effect of reducing the surface diffusion of gold which hinder the initial coarsening of ligaments and prevents interior silver atoms from being exposed and dissolved. As a result, the pore and ligment size are finer, but higher residual silver of NPG samples. NPG with pore size down to 2 nm and the ligament 4.0 nm was successfully fabricated with 13.32 mM SDS in perchloric acid solution. The surface diffusion coefficient of Au atoms was 1.6 × 10−24 m2·s−1, nearly 3 orders of magnitude smaller than that of Au atoms in the absence of SDS (2.8 × 10−21 m2·s−1). Nanoindentation results demonstrated that high residual silver content made NPG samples harder and stiffer，the specific surface areas of NPG with 6.66 mM SDS was 190 m2 g−1 by BET. This work provided very important clues on how to control the crack free ultrafine nanoporous structure of other materials. [ABSTRACT FROM AUTHOR]

Ammonium dinitramide (ADN) has the advantages of chlorine free, low characteristic signal and high energy compared with ammonium perchlorate (AP), which is the most likely oxidant to replace ammonium perchlorate. Therefore, we conducted theoretical calculations to analyze the influence of oxidant content and RDX content on the detonation parameters of composite explosives. We compared the detonation parameters of ADN-based composite explosives with AP-based composite explosives, then verify the theoretical calculation analysis results through actual testing. The main research conclusions of this paper are as follows: (i) The detonation parameters of ADN based composite explosive are higher than those of AP-based composite explosive, in which the detonation velocity is about 3.3%~17.2% higher, the detonation heat is about 0.65% ~41.8% higher, and the explosion volume is about 1.6% ~11.6% higher; (ii) the average detonation velocity of the ADN-based explosives tested in practice is 20.4% and 3% higher than that of AP-based explosives respectively, which is basically consistent with the theoretical calculation results. However, the work capacity is lower than that of AP-based composite explosive. [ABSTRACT FROM AUTHOR]

In order to clarify the combustion-supporting mechanism of fluoropolymers, this work focuses on the atomic details of the oxidation of Al nanoparticles with the fluoropolymers and O2, using reactive dynamics simulations. The results show that the combustion properties of Al–fluoropolymer composites are positively correlated with the fluorine content contained in the fluoropolymers. This is because more Al–O and Al–F bonds are formed, resulting in greater energy release, and the fluoropolymer is efficient in preventing the sintering of aluminum powder during combustion. In addition, the erosion of the alumina layer during the ignition phase results in a considerable boost in the combustion performance of the aluminum particles. Surprisingly, a micro-explosion behavior is found in Al–fluoropolymer composites during combustion, which leads to a much higher oxidation rate of aluminum powder. Our results emphasize the erosion of the alumina layer by F atoms, which provides insights into the atomic-scale reaction mechanism between Al and the fluoropolymers. [ABSTRACT FROM AUTHOR]

In this paper, based on the lift-type wind turbine, an adaptive double-drive lift–drag composite vertical-axis wind turbine is designed to improve the wind energy utilization rate. A drag blade was employed to rapidly accelerate the wind turbine, and the width of the blade was adaptively adjusted with the speed of the wind turbine to realize lift–drag conversion. The aerodynamic performance analysis using Fluent showed that the best performance is achieved with a blade curvature of 30° and a drag-type blade width ratio of 2/3. Physical experiments proved that a lift–drag composite vertical-axis wind turbine driven by dual blades can start when the incoming wind speed is 1.6 m/s, which is 23.8% lower than the existing lift-type wind turbine's starting wind speed of 2.1 m/s. At the same time, when the wind speed reaches 8.8 m/s, the guide rail adaptive drag-type blades all contract and transform into lift-type wind turbine blades. The results show that the comprehensive wind energy utilization rate of the adaptive dual-drive lift–drag composite vertical-axis wind turbine was 5.98% higher than that of ordinary lift-type wind turbines and can be applied to wind power generation in high-wind-speed wind farms. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to improve the device performance from the perspective of reducing ohmic contact resistance; the effects of different electrode structures and alloying parameters on the series resistance and power-current-voltage of laser diodes (LDs) have been investigated in this paper. Design/methodology/approach: Four groups of p-GaAs side metal electrodes with different metal layer arrangements and thicknesses are fabricated for the investigated LDs. The investigated p-GaAs side electrodes are based on Ti/Pt/Au material and the n-GaAs side metal electrodes all have a same structure of Ni/Ge/Ni/Au/Ti/Pt/Au. The LDs with different electrodes were alloyed at 380°C for 60 s and 420°C for 80 s. Findings: The experimental results show that the series resistance decreases by 14%–20%, the output power increases by 2%–2.2% and the conversion efficiency increases by 1.69%–2.16% for the LDs prepared with optimized alloying parameters (420°C for 80 s). The laser diode with p-GaAs side Ti/Pt/Au electrode of 30/70/100 nm has the best device characteristics under both annealing conditions. Originality/value: The utilization of this improvement on ohmic contact property in electrode is not only very important for upgrading high-power LDs but also helpful for GaAs-based microelectronic devices such as HBT and monolithic microwave integrated circuit. [ABSTRACT FROM AUTHOR]

Air pollution is related to the development of the national economy and people's livelihoods. Formaldehyde, as one of the main pollutants in the air, affects people's physical and mental health. In order to remove formaldehyde and better protect the health of residents, it is necessary to develop efficient adsorption materials. In this study, APMDS-modified cellulose composite aerogel microcrystalline was investigated. The adsorption of formaldehyde by the MCC/APMDS (Microcrystalline Cellulose/N-(2-aminoethyl)-3- Aminopropyl Methyl Dimethoxysilane) composite aerogel mainly relied upon the reaction of the protonated –NH3+ group in APMDS with formaldehyde to form a Schiff base to achieve the effect of deformaldehyde. Meanwhile, the modification of the aerogel reduced the pore volume and specific surface area, and the average pore size increased to 14.56 nm, which enhanced the adsorption capacity of formaldehyde, and the adsorption amount reached 9.52 mg/g. This study provides valuable information for the preparation of adsorbent materials with high formaldehyde adsorption capacity for air purification. [ABSTRACT FROM AUTHOR]

Objective: To systematically evaluate the rehabilitation effect of non-invasive brain stimulation (NIBS) on disorder of consciousness (DOC) after brain injury and compare the effects of different NIBSs. Methods: Randomized controlled trials (RCTs) on the effect of NIBS on DOC after brain injury were retrieved from the PubMed, Cochrane Library, Web of Science, CNKI, VIP, Wanfang Data, and CBM databases from inception to October 2022. The risk of bias and quality of the trials were assessed following the Cochrane Handbook of Systematic Reviews and the physiotherapy evidence database Jadad Scale. Statistical analysis was conducted with RevMan 5.4 and R Studio. This study was registered on PROSPERO (No. CRD42022371334). Results: A total of 28 articles were included involving 1118 patients. Meta-analysis showed that NIBS combined with routine rehabilitation had the highest effect than the routine rehabilitation and the sham NIBS combined with routine rehabilitation. The cumulative probability ranking results showed that the rTMS was best. The order of network meta-analysis with GCS (Glasgow Coma Scale) as the outcome index is rTMS combined with routine rehabilitation > tDCS combined with routine rehabilitation > routine rehabilitation > NIBS sham stimulation combined with routine rehabilitation. The order of network meta-analysis with CRS-R (Coma Recovery Scale–Revised) as the outcome index is rTMS combined with routine rehabilitation > tDCS combined with routine rehabilitation > NIBS sham stimulation combined with routine rehabilitation > routine rehabilitation. For patients with different conditions of DOC, the subgroup analysis results showed that rTMS improved the effect of patients with severe DOC better than those with unclear conditions of DOC, but the overall results of the two groups were not significantly different. On the contrary, the effect of tDCS on patients with DOC whose condition was not clear was better than that on patients with severe DOC, and the effect on patients with severe DOC was not significant (P > 0.05). In terms of safety, only 9 articles mentioned ADRs in the included literature, including 8 articles without ADRs, and 1 article with ADRs. Conclusion: Based on the research results of various indicators, NIBS can improve DOC after brain injury, and the rTMS is the best. Limited by the number and the quality of literature, the above conclusions need more high-quality research to verify. [ABSTRACT FROM AUTHOR]

The Omicron variants of SARS-CoV-2 have emerged as the dominant strains worldwide, causing the COVID-19 pandemic. Each Omicron subvariant contains at least 30 mutations on the spike protein (S protein) compared to the original wild-type (WT) strain. Here we report the cryo-EM structures of the trimeric S proteins from the BA.1, BA.2, BA.3, and BA.4/BA.5 subvariants, with BA.4 and BA.5 sharing the same S protein mutations, each in complex with the surface receptor ACE2. All three receptor-binding domains of the S protein from BA.2 and BA.4/BA.5 are "up", while the BA.1 S protein has two "up" and one "down". The BA.3 S protein displays increased heterogeneity, with the majority in the all "up" RBD state. The different conformations preferences of the S protein are consistent with their varied transmissibility. By analyzing the position of the glycan modification on Asn343, which is located at the S309 epitopes, we have uncovered the underlying immune evasion mechanism of the Omicron subvariants. Our findings provide a molecular basis of high infectivity and immune evasion of Omicron subvariants, thereby offering insights into potential therapeutic interventions against SARS-CoV-2 variants. [ABSTRACT FROM AUTHOR]

In this paper, we consider a time fractional diffusion system with a nonlinear memory term in a bounded domain. We mainly prove some blow-up and global existence results for this problem. Moreover, we also give the decay estimates of the global solutions. Our proof relies on the eigenfunction method combined with the asymptotic behavior of the solution of a fractional differential inequality system, the estimates of the solution operators and the asymptotic behavior of the Mittag–Leffler function. In particular, we give the critical exponents of this problem in different cases. Our results show that, in some cases, whether one of the initial values is identically equal to zero has a great influence on blow-up and global existence of the solutions for this problem, which is a remarkable property of time fractional diffusion systems because the classical diffusion systems can not admit this property. [ABSTRACT FROM AUTHOR]

As shown in Figure 1B, the growth rates of 4th- and 5th-instar larvae of gypsy moth in the GM inoculation group were significantly lower than those in the CK group, while the growth rates of 3rd-5th-instar larvae in the GI treatment group were higher as compared to the CK group. In the present study, gut microbiota and fat body metabolism of gypsy moth larvae showed two completely opposite trends in response to GM or GI-colonized I Populus alba i × I P. berolinensis i seedlings. These results indicated that the metabolic disorder of gypsy moth larvae in the GM treatment group occurred, consistent with the growth retardation of gypsy moth larvae mentioned above. Altogether, the decrease in gut beneficial bacteria and microbial function disorder is one of the main reasons for the growth retardation of gypsy moth larvae in the GM group, while the improved gut environment and the enhanced metabolic functions of gut flora are responsible for the increased larval growth in the GI group. [Extracted from the article]

Abnormal lipid metabolism often occurs under hypoxic microenvironment, which is an important energy supplement for cancer cell proliferation and metastasis. We aimed to explore the lipid metabolism characteristics and gene expression features of pancreatic ductal adenocarcinoma (PDAC) related to hypoxia and identify biomarkers for molecular classification based on hypoxic lipid metabolism that are evaluable for PDAC prognosis and therapy. The multiple datasets were analyzed integratively, including corresponding clinical information of samples. PDAC possesses a distinct metabolic profile and oxygen level compared with normal pancreatic tissues, according to the bioinformatics methods. In addition, a study on untargeted metabolomics using Ultra Performance Liquid Chromatography Tandem Mass Spectrometry(UPLC-MS) revealed lipid metabolites differences affected by oxygen. Analysis of PDAC gene expression profiling in The Cancer Genome Atlas (TCGA) revealed that the sphingolipid process correlates closely with HIF1α. According to the characters of HIF-1 and sphingolipid, samples can be clustered into three subgroups using non-negative matrix factorization clustering. In cluster2, patients had an increased survival time. Relatively high MUC16 mutation arises in cluster2 and may positively influence the cancer survival rates. This study explored the expression pattern of lipid metabolism under hypoxia microenvironment in PDAC. On the basis of metabolic signatures, we identified the prognosis subtypes linking lipid metabolism to hypoxia. The classifications may be conducive to developing personalized treatment programs targeting metabolic profiles. [ABSTRACT FROM AUTHOR]

There are three key components at the core of the mpox virus (MPXV) DNA polymerase holoenzyme: DNA polymerase F8, processivity factors A22, and the Uracil-DNA glycosylase E4. The holoenzyme is recognized as a vital antiviral target because MPXV replicates in the cytoplasm of host cells. Nucleotide analogs such as cidofovir and cytarabine (Ara-C) have shown potential in curbing MPXV replication and they also display promise against other poxviruses. However, the mechanism behind their inhibitory effects remains unclear. Here, we present the cryo-EM structure of the DNA polymerase holoenzyme F8/A22/E4 bound with its competitive inhibitor Ara-C-derived cytarabine triphosphate (Ara-CTP) at an overall resolution of 3.0 Å and reveal its inhibition mechanism. Ara-CTP functions as a direct chain terminator in proximity to the deoxycytidine triphosphate (dCTP)-binding site. The extra hydrogen bond formed with Asn665 makes it more potent in binding than dCTP. Asn665 is conserved among eukaryotic B-family polymerases. [Display omitted] • 3.0 Å cryo-EM structure of MPVX F8/A22/E4 with its bound competitive inhibitor Ara-CTP • Ara-CTP forms a strong extra hydrogen bond with Asn665 compared to dCTP • Thumb and Finger regions undergo substantial movements when binding to dsDNA Shen et al. report high-resolution cryo-EM structures of the MPXV DNA polymerase holoenzyme F8/A22/E4 with its bound substrate deoxycytidine triphosphate (dCTP) and competitive inhibitor cytarabine triphosphate (Ara-CTP). Structural comparisons reveal the conformational changes occurring during the transition from an inactive state to active state upon dsDNA binding and dCTP incorporation. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) have been acknowledged as a potential platform for heterogeneous photoredox cross-coupling due to their excellent chemical stability, admirable controllability, and extremely prominent surface area. However, synthesizing COFs with bidentate ligand units and utilizing active sites remain a grand challenge. Herein, we report a promising new family of 2,6-pyridinedicarboxaldehyde-bis-(p-aminophenylimine)-based two-dimensional (2D) COFs (PP-COF) using an amine monomer and classic tri-aldehydes. On this basis, dispersed Ni single-atom sites were immobilized on three-types imine-based bi-coordinated 2D COFs (Ni SAS-PP-COF) as heterogeneous dual photoredox catalysts for photo/Ni dual-catalyzed C–N cross-coupling between aryl bromides and alkyl/sulfo amines. Under solar energy irradiation, PP-COF could absorb light to generate electrons and holes, then the photogenerated electrons are transferred to Ni sites to reduce divalent nickel to monovalent nickel. Monovalent nickel is necessary to drive the nickel catalytic cycle. Due to the increased charge separation and abundant active sites, the state-of-the-art Ni SAS-PP-COFs catalyst achieves excellent catalytic performance in comparison of pristine PP-COF. The heterogeneous Ni SAS-PP-COF catalytic system not only confirms the prospect of COFs as potential photoredox/transition-metal dual catalysts, but also provides in-depth insights into the synthesis of functional COFs toward practical metallaphotocatalytic application. [Display omitted] ● Three-types imine-based bi-coordinated 2D COFs were synthesized. ● Heterogeneous catalysts exhibits high activity for photo/Ni dual-catalyzed C–N cross-coupling. ● The reaction substrate has good compatibility. ● This performance is ascribed to increased charge separation and abundant active sites. [ABSTRACT FROM AUTHOR]

Tumor hypoxia, limited H 2 O 2 levels, and abundant glutathione (GSH) in the tumor microenvironment (TME) pose challenges for high-efficiency reactive oxygen species (ROS)-mediated therapies. To address these limitations, an intelligent ROS-mediated nanoplatform, Ce6@ZIF-8/PDA/CuO 2 /HA (CZPCH), with photodynamic activity, self-supplied H 2 O 2 , Fenton-like reaction, GSH-depletion and photothermal activity was designed for efficient tumor treatment. In the acidic TME, CuO 2 in CZPCH deposits into Cu2+ and H 2 O 2 , consuming GSH and triggering Fenton-like reactions to generate hydroxyl radical (•OH), enabling efficient chemodynamic therapy (CDT). Moreover, the presence of Ce6 and PDA enables CZPCH to exhibit excellent singlet oxygen (1O 2) and temperature increase performance 660 nm and 808 nm laser irradiation, respectively, resulting in efficient photodynamic therapy (PDT) and photothermal therapy (PTT) efficacy. Interestingly, the temperature increase from PTT significantly enhances •OH and 1O 2 generation, achieving high-efficiency ROS-based therapeutic efficacy. This synergistic CDT/PDT/PTT treatment demonstrates excellent anti-tumor efficacy and illuminates novel ROS-based therapeutic strategy design. [Display omitted] [ABSTRACT FROM AUTHOR]

Chiral and achiral mechanical metamaterials are designed via spherical tiling. The 3D chiral designs show an interesting coupled compression-twisting behavior, while the 3D achiral designs show auxetic behavior. Also, besides the cellular-type chiral and achiral designs, composite-type of each design are created by adding soft matrix to the cellular designs. The designs are fabricated via multi-material 3D printing. Mechanical uni-axial compression experiments are performed on the 3D printed specimens and the experimental results are compared with finite element (FE) simulations. By jointly tailoring the chiral geometry and material combination, the effective mechanical properties and the deformation mechanisms can be tuned in a large range. In addition, a continuum-level material model was developed to predict the constitutive relationship. The results show that the material model can well predict the effective mechanical properties of the chiral 3D mechanical metamaterials. [ABSTRACT FROM AUTHOR]

Aims: To investigate the exposure–response (E‐R) relationship, including exposure–efficacy and exposure–safety, of ropeginterferon alfa‐2b treatment in patients with polycythaemia vera (PV). Methods: Based on the results of the phase II trial A20‐202 regarding ropeginterferon alfa‐2b in patients with PV, E‐R analyses were performed to evaluate the efficacy and safety of the given dosing regimen. The E‐R analyses were based on logistic and linear regression and the relationship between exposure to ropeginterferon alfa‐2b and key efficacy and safety variables. The key efficacy variables included complete haematologic response (CHR) and reduction of the driver mutation JAK2V617F. The safety variable was treatment‐related adverse events (TRAEs). Results: A clear relationship between the exposure to ropeginterferon alfa‐2b and CHR was observed, with an increase in drug exposure resulting in an increased probability of achieving CHR. Similar CHR probabilities were observed in the third and fourth quantiles of the average concentration at Week 24. The results from the exposure–JAK2V617F model indicated that the JAK2V617F allele burden decreased with increasing exposure to ropeginterferon alfa‐2b and baseline body surface area. Exposure–safety analysis revealed a risk of AEs associated with transaminase abnormalities, which were not associated with clinical significance. Conclusions: Our analyses have shown that patients with PV treated with ropeginterferon alfa‐2b had an increased probability of achieving CHR and a molecular response with acceptable safety risks at the 250–350–500 μg titration dosing regimen. This study has provided the relevant data for the application of a biologics licence of ropeginterferon alfa‐2b for PV treatment in China. [ABSTRACT FROM AUTHOR]

Phytophthora sojae is an important model species for oomycete functional genomics research. Recently, a CRISPR/Cas9‐mediated genome‐editing technology has been successfully established in P. sojae, which has been rapidly and widely applied in oomycete research. However, there is an emerging consensus in the biological community that a complete functional gene research system is needed such as developed in the investigations in functional complementation carried out in this study. We report the development of an in situ complementation method for accurate restoration of the mutated gene. We targeted a regulatory B‐subunit of protein phosphatase 2A (PsPP2Ab1) to verify this knockout and subsequent complementation system. We found that the deletion of PsPP2Ab1 in P. sojae leads to severe defects in vegetative hyphal growth, soybean infection, and loss of the ability to produce sporangia. Subsequently, the reintroduction of PsPP2Ab1 into the knockout mutant remedied all of the deficiencies. This study demonstrates the successful implementation of an in situ complementation system by CRISPR/Cas9, which will greatly accelerate functional genomics research of oomycetes in the post‐genomic era. [ABSTRACT FROM AUTHOR]

The relative position between the pediatric upper airway and the inhalation device during real inhalation administration has significant effects on the delivery efficiency of orally inhaled drugs. Morphological variability plays an important role in this process. However, the mouth-throat differences between adults and children were usually neglected because most of the commercial inhalation devices currently are designed for adults or older adolescents. The main objective of this study is to investigate these effects by four realistic pediatric mouth-throat (RMT) geometries. In addition, an idealized mouth-throat (IMT) model was developed to validate the numerical model and to compare with the RMT models. Computational fluid dynamics (CFD) simulations were performed to investigate the flow pattern and deposition pattern in these models and the results were compared with the cascade impactor experiments, replica experiments and in vivo results. No significant correlation (p > 0.1) between the relative position parameters and inhaler insertion depth can be noticed among the RMT models. Notably, significant variability in the inhaler posture was observed in RMT models, especially for the S4 model. Airflow structure shows that the RMT model has a complex onset of turbulence, reverse flow and subsequently vortex formation when compared with the IMT model. The oral cavity is the region with the largest deposition fraction (DF) and deposition efficiency (DE). The DF and DE of the oral cavity are negatively correlated to the position parameter (L m) when mass median aerodynamic diameter (MMAD) of indacaterol 150 μg was utilized as the input particle parameter. The relative position between the inhaler and oral cavity has significant effects on the particle transport and deposition. Furthermore, in silico results overestimated the lung deposition in comparison to the in vivo and experimental results when MMAD was used as input. To resolve the disparity between the in silico and in vivo results, a modified prediction method based on the cascade impactor and original in silico results was proposed and a good correlation of the relative contribution of pulmonary absorption to total systemic exposure (f lung) was found between the predicted and observed results. The findings of present work will provide useful information in understanding the particle transport and deposition in the pediatric airways for the design of inhaler. [Display omitted] • Pediatric mouth-inhaler position is unrelated to inhaler insertion depth • Oral cavity deposition negatively correlates to the mouth-inhaler position parameter • Modified prediction methods can improve the in silico - in vivo correlation [ABSTRACT FROM AUTHOR]

Although 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) is one of the best high-energy explosives, its application is severely limited by its high sensitivity. Herein, a composite wax-film with interfacial crosslinking anti-falling was designed and fabricated to desensitize CL-20. It was filled with nano-silica powder (n-Si), nano-graphenes (n-GPNs) and multi-walled carbon nanotubes (MWCNTs) as insensitive enhancers. A unique and stable core-shell composite explosive was prepared, and characterized by DSC, SEM, TEM, XRD, XPS as well as mechanical sensitivity tests. The results suggested that the functional group interaction and structural strengthening between enhancers and microcrystalline wax (MW) further enhanced the desensitization ability of the composite film for CL-20. Because of the hydrogen bonding and thickening enhancement, the CL-20 crystal was uniformly coated with a nano-composite film. Three enhancers were demonstrated to be highly compatible with CL-20. In comparison with MW@CL-20, The E a , T p0 and T b of the composites containing n-GPNs increased by >375.27 kJ·mol−1, 21.04 °C and 18.27 °C, respectively. The SEM and XPS results showed that the composite performed a complete core-shell structure with thermal softening resistance and superior coverage (98.20 %). The insensitive enhancer was also distributed and embedded in the MW-film matrix. Besides, the anti-fall and cross-linking properties of the film enable the mechanical sensitivity of the composite explosive to reach to a level better than that of WO 3 /Al nanothermite with 5 wt% polyaniline and polymer-bonded explosive (PBX) with 95 wt% LLM-105 and 5 wt% ternary composite. The heterogeneous composites demonstrated excellent mechanical safety and high energy performance. These findings can provide a reference for the efficient desensitization of CL-20. [Display omitted] • A nano-composite film based on cross-linking network enhancement was designed for explosive crystal desensitization. • The homogeneous core-shell composite explosive was fabricated using a simple and safe method. • The coating containing n-Si had a better cost advantage and a higher desensitization ability than that of GNPs and MWCNTs. • The coexistence of high energy and low sensitivity of CL-20-based composite explosives was achieved. [ABSTRACT FROM AUTHOR]

The preparation and energy release mechanism of highly reactive n-Al/F-polymer metastable intermixed composites are both desirable and challenging. In this study, we employed an optimized electrospray sampling strategy to significantly enhance the reaction activity of aluminum-based MICs, as well as their combustion performance. It is evident that the optimization of the sampling strategy yielded remarkable results. Compared to the physical mixture, MICs-1 exhibited a 7.2-fold and 9.9-fold increase in P max and P max /Δ t , respectively. The combustion rate experienced an 8.5-fold improvement, and the energy release efficiency rose from 52.18 % to 68.11 %. An analysis of the energy evolution mechanism reveals a mitigation of the reactive sintering phenomenon observed in MICs-1. The presence of PVDF facilitates the reactivity of aluminum powders by selectively corroding the alumina shell. The reaction kinetics parameters indicate that MICs-1 demonstrates characteristic three-step reaction behavior and exhibits a lower reaction energy barrier. Furthermore, ReaxFF molecular dynamics simulations demonstrate the adsorption and dissociation of PVDF on the surface of aluminum powders, leading to erosion defects in the alumina crystal structure. These defects, in turn, induce the ignition reaction. • Activated aluminum base metastable intermixed composites is designed. • The erosion-activation mechanism of pre-ignition reaction is demonstrated. • The process from surface defect formation to ignition of ANPs is verified by reactive molecular dynamics simulation. [ABSTRACT FROM AUTHOR]

Aluminum (Al) is widely used to improve the combustion performance of energetic material formulations. However, only a limited part of the energy released by the oxidation of aluminum works because of ignition delay and incomplete combustion. In order to overcome this defect, a mechanical activation-sintering method is developed to prepare Al/PTFE composites for enhancing the combustion performance of Al powders. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used to analyze the morphology and structures of the samples. An orthogonal experiment is employed to filter the best preparation parameters by evaluating the combustion pressure in a closed vessel. With the conditions of 65 : 35 (g/g, mass ratio of Al and PTFE), 12 : 1 (g/g, ball-to-powder weight ratio, BPR), 250 rpm (rotation speed of ball milling container) and 45 min (milling duration), the Al powders are coated uniformly by PTFE and the composites exhibit excellent dispersity. By optimizing the preparation conditions, the maximum pressure, pressurization rate as well as the flame propagation are highly improved, compared to that of a simple mixture of Al powders and PTFE. This work provides a feasible and universal method to prepare aluminum-containing composites. [ABSTRACT FROM AUTHOR]

The interfacial strength between explosive crystal and binder usually plays a key role in exhibiting excellent mechanical properties of composite explosives. In this paper, high energetic crystal octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX) was coated by the typical binder cis‐1,4‐polybutadiene rubber (BR), then two silane coupling agents were added to the composite particles to enhance the interface strength. The results showed that the BR binder modified by silane coupling agent is easier to spread on the surface of HMX crystal, and form a good coating effect. In the mechanical properties test of composite particles, (3‐Aminopropyl) trimethoxysilane significantly improved the tensile and compressive strength of HMX/BR based composite particles, while 3‐(Triethoxysilyl) propionitrile decreased the mechanical properties of the composite particles. [ABSTRACT FROM AUTHOR]

To improve the ignition and combustion properties of n‐Al powders, n‐Al/Ni composite particles were prepared by replacement reaction under alkaline environment. In the anhydrous ethanol system, the effect of solution parameters on sample preparation was studied, and the preparation technology of n‐Al/Ni was accordingly optimized. The chemical constituents, phase, morphology and combustion performances of n‐Al/Ni were characterized by chemical titration, XRD, SEM, EDS and combustion duration test, respectively. The results showed that the optimized replacement reaction method can modify the n‐Al powders by nickel well, and it was appropriate to use OH−1 corresponding to consume 60 % alumina in the n‐Al powders and Ni2+ equal to 12.35 % mass fraction of n‐Al powders. It can be seen from the SEM images that the samples have a dispersive spherical morphology with a uniform distribution of nickel overall the samples. And the XRD results confirmed that nickel exists in the samples as a metallic substance. The results of chemical titration indicated that the content of active aluminum in the optimal sample was slightly higher than that of raw n‐Al, but considering Ni, the content of reactive substance in the sample was greatly increased. The combustion duration test also proved that the combustion performance of n‐Al/Ni was significantly improved. In conclusion, the improved properties promise a further enhanced prospect of n‐Al in energetic materials. [ABSTRACT FROM AUTHOR]

Stroke induces a robust inflammatory response. However, it still lacks a systematic view of the various immune cell types due to the limited numbers of fluorophore used in the traditional FACS technique. In our current study, we utilized the novel technique mass cytometry (CyTOF) to analyze multiple immune cell types. We detected these immune cells from the ischemic brain, peripheral blood, spleen, and bone marrow at different time courses after stroke. Our data showed (1) dynamic changes in the immune cell numbers in the ischemic brain and peripheral organs. (2) The expression levels of cell surface markers indicate the inflammation response status after stroke. Interestingly, CD62L, a key adhesion molecule, regulates the migration of leukocytes from blood vessels into secondary lymphoid tissues and peripheral tissues. (3) A strong leukocyte network across the brain and peripheral immune organs was identified using the R program at day 1 after ischemia, suggesting that the peripheral immune cells dramatically migrated into the ischemic areas after stroke. This study provides a systematic, wide view of the immune components in the brain and peripheral organs for a deep understanding of the immune response after ischemic stroke. [ABSTRACT FROM AUTHOR]

Structured illumination microscopy (SIM) achieves doubled spatial resolution through exciting the specimen with high-contrast, high-frequency sinusoidal patterns. Such an illumination pattern can be generated by laser interference or incoherent structured patterns. Opto-electronic devices, such as a Spatial Light Modulator (SLM) or a Digital Micro-mirror Device (DMD), can provide rapid switch of illumination patterns for SIM. Although the DMD is much more cost-effective than the SLM, it was previously restricted in association with incoherent light sources, as its diffractive orders are related to the incident angle and the wavelength of coherent incidence. To extend its application with coherent illumination, here, we model the DMD as a blazed grating and simulate the effect with DMD pattern changes in the SIM. With careful analysis of the illumination contrast along different angles and phases, we report a fast, high-resolution, and cost-efficient SIM with DMD modulation. Our home-built laser interference-based DMD-SIM (LiDMD-SIM) reveals the nuclear pore complex and microtubule in mammalian cells with doubled spatial resolution. We further proposed the multi-color LiDMD-SIM concept by jointly employing the DMD ON/OFF states with different incident angles for different wavelengths, with high contrast and maximum resolution enhancement. [ABSTRACT FROM AUTHOR]

In this paper, we deal with two fractional boundary value problems which have linear growth and quadratic growth about the fractional derivative in the nonlinearity term. By using variational methods coupled with the iterative methods, we obtain the existence results of solutions. To the best of the authors' knowledge, there are no results on the solutions to the fractional boundary problem which have quadratic growth about the fractional derivative in the nonlinearity term. [ABSTRACT FROM AUTHOR]

Eukaryotic heterotrimeric guanine nucleotide-binding proteins consist of α, β, and γ subunits, which act as molecular switches to regulate a number of fundamental cellular processes. In the oomycete pathogen Phytophthora sojae, the sole G protein α subunit (Gα; encoded by PsGPA1) has been found to be involved in zoospore mobility and virulence, but how it functions remains unclear. In this study, we show that the Gα subunit PsGPA1 directly interacts with PsYPK1, a serine/threonine protein kinase that consists of an N-terminal region with unknown function and a C-terminal region with a conserved catalytic kinase domain. We generated knockout and knockout-complemented strains of PsYPK1 and found that deletion of PsYPK1 resulted in a pronounced reduction in the production of sporangia and oospores, in mycelial growth on nutrient poor medium, and in virulence. PsYPK1 exhibits a cytoplasmic-nuclear localization pattern that is essential for sporangium formation and virulence of P. sojae. Interestingly, PsGPA1 overexpression was found to prevent nuclear localization of PsYPK1 by exclusively binding to the N-terminal region of PsYPK1, therefore accounting for its negative role in sporangium formation. Our data demonstrate that PsGPA1 negatively regulates sporangium formation by repressing the nuclear localization of its downstream kinase PsYPK1. Author summary: Eukaryotic heterotrimeric guanine nucleotide-binding proteins consist of α, β, and γ subunits, which act as molecular switches to regulate a number of fundamental cellular processes. In oomycete plant pathogen Phytophthora sojae, previous research showed that G protein α subunit is involved in zoospore motility and pathogenicity. However, the elaborate functions of G protein α subunit remain largely unknown. Here, we identified a serine/threonine protein kinase, PsYPK1, which directly interacts with the G protein α subunit (PsGPA1) in P. sojae. We found that PsYPK1 regulates the production of sporangia and oospores, mycelia growth in nutrient poor medium, and pathogenicity in P. sojae. We further revealed that PsYPK1 exhibits a cytoplasmic-nuclear localization pattern that is essential for sporangium formation and the pathogenicity of P. sojae. Interestingly, PsGPA1 overexpression was found to prevent nuclear localization of PsYPK1 by exclusively binding to the N-terminal region of PsYPK1, accounting for the negative role of PsGPA1 in sporangium formation. Our study is the first to show G protein signaling is transmitted to a downstream effector to regulate the development and pathogenicity of an oomycete pathogen, which opens new avenues for researches on animal and plant pathogens and host-microbe interactions. [ABSTRACT FROM AUTHOR]

• Improve the theory of Epipolar Focus Spectrum (EFS) and give the Sampling analysis of EFS. • An EFS-based learning framework for dense-view light field reconstruction is proposed. • The proposed method can guarantee the cross-view consistency for fulldepth/ disparity light field reconstruction. • The proposed method exhibits superior performance under large disparities. Existing light field (LF) representations, such as epipolar plane image (EPI) and sub-aperture images, do not consider the structural characteristics across the views, so they usually require additional disparity and spatial structure cues for follow-up tasks. Besides, they have difficulties dealing with occlusions or large disparity scenes. To this end, this paper proposes a novel Epipolar Focus Spectrum (EFS) representation by rearranging the EPI spectrum. Different from the classical EPI representation where an EPI line corresponds to a specific depth, there is a one-to-one mapping from the EFS line to the view. By exploring the EFS sampling task, the analytical function is derived for constructing a non-aliasing EFS. To demonstrate its effectiveness, we develop a trainable EFS-based pipeline for light field reconstruction, where a dense light field can be reconstructed by compensating the missing EFS lines given a sparse light field, yielding promising results with cross-view consistency, especially in the presence of severe occlusion and large disparity. Experimental results on both synthetic and real-world datasets demonstrate the validity and superiority of the proposed method over SOTA methods. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we prove sharp blow-up and global existence results for a time fractional subdiffusion equation with nonlinear memory in a bounded domain. The critical exponents of this problem are determined when α < γ and α ≥ γ , respectively. [ABSTRACT FROM AUTHOR]

Abstract We study the following time fractional complex nonlinear Ginzburg–Landau equation: { e − i ω 0 C D t α u − △ u = e i γ | u | p − 1 u , x ∈ R N , t > 0 , u (0 , x) = u 0 (x) , x ∈ R N , where 0 < α < 1 , γ ∈ R , − π + π α 2 < ω < π − π α 2 , p > 1 , u 0 ∈ L q (R N) (q ≥ q c = N (p − 1) 2 and q ≥ 1) is a complex-valued function, and D t α 0 C u = ∂ ∂ t 0 I t 1 − α (u (t , x) − u (0 , x)) , where I t 1 − α 0 denotes a left Riemann–Liouville fractional integral of order 1 − α. By defining two operators and establishing some estimates of them, we prove the well-posedness of the mild solution for this problem in C ([ 0 , T ] , L q (R N)) and L 2 r q α N (r − q) ((0 , T) , L r (R N)) , where r satisfies 1 / q − 1 / r < 2 / N. Moreover, we also obtain the existence of global solutions when ‖ u 0 ‖ L q c (R N) is sufficiently small. [ABSTRACT FROM AUTHOR]

Focusing on the first domestic coking flue gas desulfurization and denitration integrated unit in China, the current condition of inlet flue gas indices cannot be determined timely owing to the large detection lag and complex upstream coking process, which is extremely unfavorable for the optimal control of desulfurization and denitration process. In order to solve this problem, an intelligent integrated modeling method of flue gas SO2 concentration, O2 content and NOx concentration is proposed. Firstly, the gas flow diagram in combustion process is built, the mechanism models of SO2, NOx concentration and O2 content are established according to the principle of material balance and reaction kinetics, respectively. Then the RBF neural network is adopted to compensate the prediction error, an improved training algorithm combining optimal stopping principle and dual momentum adaptive learning rate is proposed to improve the training speed and generalization ability of neural network. Based on the practical data of two 55-hole and 6-meter top charging coke ovens in the coking group, the effectiveness and superiority of proposed model and method are verified by simulation via comparison of various methods. [ABSTRACT FROM AUTHOR]

The application of pest management involves two thresholds when the chemical control and biological control are adopted, respectively. Our purpose is to provide an appropriate balance between the chemical control and biological control. Therefore, a Smith predator-prey system for integrated pest management is established in this paper. In this model, the intensity of implementation of biological control and chemical control depends linearly on the selected control level (threshold). Firstly, the existence and uniqueness of the order-one periodic solution (i.e., OOPS) are proved by means of the subsequent function method to confirm the feasibility of the biological and chemical control strategy of pest management. Secondly, the stability of system is proved by the limit method of the successor points' sequences and the analogue of the Poincaré criterion. Moreover, an optimization strategy is formulated to reduce the total cost and obtain the best level of pest control. Finally, the numerical simulation of a specific model is performed. [ABSTRACT FROM AUTHOR]

In this paper, we study the blow-up and global existence of solutions to the following time fractional nonlinear diffusion equations 0 C D t α u − △ u = 0 I t 1 − γ (| u | p − 1 u) , x ∈ R N , t > --> 0 , u (0 , x) = u 0 (x) , x ∈ R N , $$\begin{array}{} \displaystyle \left\{\begin{array}{l}{_0^CD_t^\alpha u}-\triangle u={_0I_t^{1-\gamma}}(|u|^{p-1}u), \, \, x\in \mathbb{R}^N,\, \, t\gt 0,\\ u(0,x)=u_0(x),\, \, x\in \mathbb{R}^N, \end{array}\right. \end{array}$$ where 0 < α < γ < 1, p > 1, u0 ∈ C0(ℝN), 0 I t θ $\begin{array}{} {_0I_t^{\theta}} \end{array}$ denotes left Riemann-Liouville fractional integrals of order θ. 0 C D t α u = ∂ ∂ t 0 I t 1 − α $\begin{array}{} {_0^CD_t^\alpha u}=\frac{\partial}{\partial t}{_0I_t^{1-\alpha}} \end{array}$ (u(t, x) − u(0, x))}. Let β = 1 − γ. We prove that if 1 < p < p∗ = max { 1 + β α , 1 + 2 (α + β) α N } $\begin{array}{} \max\big\{1+\frac{\beta}{\alpha},1+\frac{2(\alpha+\beta)}{\alpha N}\big\} \end{array}$ , the solutions of (1.1) blows up in a finite time. If N < 2 (α + β) β $\begin{array}{} \frac{2(\alpha+\beta)}{\beta} \end{array}$ , p ≥ p∗ or N ≥ 2 (α + β) β $\begin{array}{} \frac{2(\alpha+\beta)}{\beta} \end{array}$ , p > p∗, and ∥u0∥Lqc(ℝN) is sufficiently small, where q c = N α (p − 1) 2 (α + β) $\begin{array}{} q_c=\frac{N\alpha(p-1)}{2(\alpha+\beta)} \end{array}$ , the solutions of (1.1) exists globally. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Develop an optimal feature extraction algorithm to capture the optimal features of wind speed fluctuations. • Introduce an error correction strategy to improve the prediction precision of wind speed. • A innovate hybrid model is successfully proposed for multi-step ahead wind speed prediction. • Design three experiments from the real wind farms to validate the availability and reliability of the developed model. Abstract Forecasting wind speed accurately is a key task in the planning and operation of wind energy generation in power systems, and its importance increases with the high integration of wind power into the electricity market. This research proposes an innovative hybrid model based on optimal feature extraction, deep learning algorithm and error correction strategy for multi-step wind speed prediction. The optimal feature extraction including variational mode decomposition, Kullback-Leibler divergence, energy measure and sample entropy is utilized to catch the optimal features of wind speed fluctuations for balancing the calculation efficiency and prediction accuracy. The deep learning algorithm based on long short term memory network, is utilized to detect the long-term and short-term memory characteristics and build the suitable prediction model for each feature sub-signal. The error correction strategy based on a Generalized auto-regressive conditionally heteroscedastic model is developed to modify the above prediction errors when its inherent correlation and heteroscedasticity cannot be ignored. Three real forecasting cases are applied to test the performance and effectiveness of the developed model. The simulation results indicate that the developed model consistently has the smallest statistical errors, and outperforms other benchmark methods. It can be concluded that the developed approach is conductive to strengthening the prediction precision of wind speed. [ABSTRACT FROM AUTHOR]

In this paper, we determine the Fujita critical exponent of the following time fractional subdiffusion equation with nonlinear memory 0CDtαu−△u=0It1−γ|u|p−1u,x∈RN,t>0,u(0,x)=u0(x),x∈RN,where 0 < α < 1, 0 ≤ γ < 1, γ ≤ α, p > 1, u0∈C0RN, 0It1−γ denotes left Riemann‐Liouville fractional integral of order 1 − γ. Let β = 1 − γ. We prove that, if 1 p∗ and ‖u0‖LqcRN is sufficiently small, where qc=Nα(p−1)2(α+β), then u exists globally. [ABSTRACT FROM AUTHOR]

Highlights • Biomimetic suture specimens were fabricated via multi-material 3D printing. • Two interesting failure mechanisms were observed from the experiments. • Advanced nonlinear FE simulations captured the two failure mechanisms. • The transition between the two failure mechanisms are also identified. Abstract Inspired by the biological sutures in nature, triangular suture specimens with different tooth tip angle and material combinations were fabricated via multi-material 3D printing. From mechanical experiments under uni-axial tension, two basic failure mechanisms were observed: tooth breakage and the cohesive failure of the interfacial layer. It was found that when the tooth tip angle increases and/or the strength of the material in the interfacial layer increases, the failure mechanism of sutures can transit from tooth breakage mode to the cohesive failure of the interfacial layer. To further understand the different failure mechanisms of sutures, advanced nonlinear finite element simulations were performed. The finite element models can predict both the overall load-displacement relation and the failure mechanisms of the 3D printed sutures. [ABSTRACT FROM AUTHOR]

Heavy metal can affect the bio-control efficiency of entomopathogenic fungi on pests, but this has not been studied in the food chain. Here, the food chain of soil- Fraxinus mandshurica - Hyphantria cunea was constructed to investigate the effect of cadmium (Cd) exposure on the susceptibility of H. cunea larvae to Beauveria bassiana (Bb) and to analyze the corresponding mechanism through larval innate immunity and energy metabolism. Cd through the food chain synergistically enhanced the susceptibility of H. cunea larvae to Bb. Cellular immunity-related parameters decreased when the Cd treatment group was compared with the control group and when the combined treatment group of Cd and Bb was compared with the Bb treatment group. Cd exposure induced hormesis on pathogen recognition and signal transduction genes of humoral immunity, but reduced the expression of effector genes. The expression of the 13 humoral immunity-related genes in the combined treatment group was lower than in the Bb treatment group. Cd exposure decreased the energy storage of H. cunea larvae before Bb infection and aggravated the disorder level of energy metabolism after Bb infection. Taken together, disturbance of innate immunity and energy metabolism improves the susceptibility of H. cunea larvae to Bb in the Cd-polluted food chain. [Display omitted] • Cd can be transferred along the "soil-plant-phytophagous insect" food chain. • Cd exposure increased the susceptibility of larvae to Beauveria bassiana. • Immunity and energy metabolism disorder were observed in Cd-exposed larvae. • Entomopathogenic fungi are suitable for bio-control in heavy metal-polluted areas. [ABSTRACT FROM AUTHOR]

Nanoplastics pollution in drinking water has aroused wide concern, but their effects on human health are still poorly understood. Herein we explore the responses of human embryonic kidney 293T cells and human normal liver LO2 cells to polystyrene nanoplastics, mainly focusing on the effects of particle sizes and enrichment of Pb2+. When the exposed particle size is higher than 100 nm, there is no obvious death for these two different cell lines. As the particle size decreases from 100 nm, cell mortality goes up. Although the internalization of polystyrene nanoplastics in LO2 cells is at least 5 times higher than that in 293T cells, the mortality of LO2 cells is lower than that of 293T cells, illustrating that LO2 cells are more resistant to polystyrene nanoplastics than 293T cells. Additionally, the Pb2+ enrichment on polystyrene nanoplastics in water can further enhance their toxicity, which should be taken seriously. The cytotoxicity of polystyrene nanoplastics to cell lines works through a molecular mechanism involving oxidative stress-induced damage of mitochondria and cell membranes, resulting in a decrease in ATP production and an increase in membrane permeability. Referenced to nanoplastics pollution in drinking water, there is no necessary to panic about the adverse effects of plastic itself on human health, but the enrichment of contaminants should get more attention. This work provides a reference for the risk assessment of nanoplastics in drinking water to human health. [Display omitted] • Toxicity of nanoplastics on two human cells is size- and concentration-dependent. • LO2 cells are more resistant to nanoplastics than 293 T cells. • Nanoplastics induce excessive oxidative damage to these two human cells. • Enrichment of Pb2+ on nanoplastics in drinking water enhances cytotoxicity. [ABSTRACT FROM AUTHOR]

A low treatment capacity and unstable operation are the main drawbacks of the anaerobic digestion of food wastes. The present work improved the efficiency and stabilization of the anaerobic digestion of food wastes using digesters with a polyamide stirring rake (DPSR) and compared it to a traditional digester with a stainless-steel stirring rake (DSSSR). The DPSR had a higher reliability and produced 3.97 times the methane yield of DSSSR in batch experiments at high loading rates (105 VS/L). Uniform design experiments were applied to investigate the relationship between methane yield and the stirring factors of the DPSR. A regression analysis of the uniform design indicated that stirring factors synergistically affect methane yield. The experiment verifying the optimal conditions showed that in the DPSR with 82 r/min stirring intensity and 10 min/d stirring time, the first 20 days of methane yield (392.1 mL/g VS) achieved to 85.26% of the theoretically derived methane yield. In brief, in the anaerobic digestion of food wastes for high methane production and stable operation, the DPSR was more beneficial for the anaerobic digestion of food wastes than the DSSSR. [ABSTRACT FROM AUTHOR]

In this paper, we establish a unilateral diffusion Gompertz model of a single population in two patches in a theoretical way. Firstly, we prove the existence and uniqueness of an order-one periodic solution by the geometry theory of differential equations and the method of successor function. Secondly, we prove the stability of the order-one periodic solution by imitating the theory of the limit cycle of an ordinary differential equation. Finally, we verify the theoretical results by numerical simulations. [ABSTRACT FROM AUTHOR]

CXCL12 overexpression improves neurobehavioral recovery during post-ischemic stroke through multiple mechanisms including promoting endothelial progenitor cells function in animal models. It has been proposed that the monomer and dimer forms possess differential chemotactic and regulatory function. The aim of present study is to explore whether a monomeric or dimeric CXCL12 plays a different role in the endothelial progenitor cells proliferation, migration, and tube-formation in vitro . In this study, we transferred monomeric, dimeric and wild type CXCL12 gene into endothelial progenitor cells via lentiviral vectors. We investigated endothelial progenitor cells function following the interaction of CXCL12/CXCR4 or CXCL12/CXCR7 and downstream signaling pathways. Our results showed that the monomeric CXCL12 transfected endothelial progenitor cells had enhanced ability in cell proliferation, migration, and tube-formation compared to that in dimeric or wild type controls ( p < 0.05). Both CXCR4 and CXCR7 were significantly overexpressed in the monomeric CXCL12 transfected endothelial progenitor cells compared to that in the dimeric or wide type controls ( p < 0.05). The function of migration, but not proliferation or tube-formation, was significantly reduced in the monomeric CXCL12 transfected endothelial progenitor cells when the cells were pre-treated with either CXCR4 inhibitor AMD3100 or siCXCR7 ( p < 0.05), suggesting this cell function was partially regulated by CXCL12/CXCR4 and CXCL12/CXCR7 signal pathways. Our study demonstrated that monomeric CXCL12 was the fundamental form, which played important roles in endothelial progenitor cells’ proliferation, migration, and tube-formation. [ABSTRACT FROM AUTHOR]

In this investigation, the mechanical response of a tri-phase system subjected to far-field compression is explored. The system includes a stiffer interfacial/coating layer surrounded by an interphase/regulation layer, and both layers are embedded in an infinite softer matrix. Both theoretical and finite element (FE) mechanical models of the system are developed. From the results of these models, three wrinkling patterns are proved to exist: (I) single-layer wrinkling mode, (II) bi-layer wrinkling mode, and (III) the simultaneous nested-wrinkling mode. The wrinkling patterns are reported to be attributed to the instability of the system. The results of FE simulations show that the theoretical model can accurately predict the instability of the system. The influences of the geometry and material properties of all three phases on the transition between the three instability modes are quantified. It reveals that the regulation layer/interphase around the interfacial/coating layer is the key to tune the wrinkling patterns. The critical physical parameters to determine the characteristics of the three instability modes are the effective thickness ratio between the regulation layer and interfacial/coating layer, the effective stiffness ratio between the interfacial/coating layer and the regulation layer and that between the interfacial/coating layer and the matrix. As an example of the application of the theoretical model, a graded interfacial wrinkling pattern is designed and verified via FE simulations. [ABSTRACT FROM AUTHOR]

The elastic mechanical properties of bi-chiral mechanical metamaterials are explored via systematic finite element simulations. Designs of bi-chiral mechanical metamaterials with both periodic and complete random handedness distributions for various handedness ratio and domain size and length aspect ratios were investigated. It is found that in general, because of the interactions at the 'twinned' intercellular boundaries between neighboring domains, the handedness ratio, handedness distribution, domain size and length aspect ratio significantly influence the overall mechanical properties of bi-chiral designs. Specifically, when handedness ratio increases and domain size decreases, the effective stiffness and the auxetic effects increases, while the effective shear modulus is much less sensitive to either the handedness ratio or the domain size. The chirality-induced normal shear coupling effect is solely determined by the handedness ratio. An empirical mechanical model was proposed to quantify the influences of 'twinned' intercellular boundaries on the effective stiffness and effective Poisson's ratio of bi-chiral designs. In addition, both upper and lower limits of the effective stiffness and the effective Poisson's ratio of bi-chiral designs are identified. [ABSTRACT FROM AUTHOR]

In this paper, we deal with the regularity of mild Solutions for fractional abstract Cauchy problem with order $${\alpha \in (1, 2)}$$ . Based on properties of solution operator and analytic solution operator, we obtain the sufficient condition under which a mild solution becomes a classical solution, and if the Cauchy problem has an analytic solution operator, we obtain more stronger results. [ABSTRACT FROM AUTHOR]

We used two common species of tree, Ailanthus altissima S. and Ulmus pumila L., as the model plants to study the behavior of abandoned reverse osmosis (RO) membrane on the phytoremediation of saline soil following a pot experiment of up to 3 years. Plants (control) or plants with the roots wrapped by abandoned RO were cultivated in pots filled with saline soil, and irrigated twice a week with tap water. Data from dry weight, tissue levels of mineral nutrients, chlorophyll (Chl), leaf protein content and content of potential toxic element (Na + ) showed that the abandoned RO significantly influenced the growth and development of the plants. A dramatic improvement of the leaf, branch and trunk biomass of A. altissima S. and U. pumila L. was observed in this study. Subsequently, the enhanced uptake of N, P and K + , and decline of Na + accumulation in the leaves, branches and trunks of A. altissima S. and U. pumila L. are suspected to be largely due to biological filter functions of the abandoned RO. In addition, Chl and protein contents were significantly ( P < 0.05) improved in both plant species treated with abandoned RO. These findings indicated that abandoned RO application could be highly beneficial for the cultivation of tree plants such as A. altissima S. and U. pumila L. in saline soil. Hence, the application of RO to both plant species can be used as a phytoremediation technique, although A. altissima S. appears to be more suitable for the phytoremediation of saline soil. [ABSTRACT FROM AUTHOR]

Oxidants, such as oxygen, cannot easily approach the core Al due to the presence of dense alumina on the surface of aluminum particles, thereby resulting in high ignition temperature and long ignition duration. To overcome this challenge, we employed the solvent/non-solvent method using Viton A (a copolymer of 1,1-difluoroethylene and hexafluoropropylene) as a coating material to prepare the core-shell Al/Viton A composite particles. An orthogonal experiment was designed to identify the optimal preparation parameters by evaluating the peak pressure in a closed vessel. The sample with the largest peak pressure was compared with raw Al and Al/Viton A (prepared by the physical mixing method) using the combustion pressure and open combustion tests to evaluate the solvent/non-solvent method. The results from the orthogonal experiment revealed that the water bath temperature exhibited the greatest influence on the coating effects. The composite prepared under a water bath temperature of 55 °C and a stirring rate of 250 rpm, using 20 mL of acetone and a 5 mL/min dripping rate of the Viton A acetone solution, were uniformly coated by Viton A, and exhibited excellent combustion characteristics. In addition, the sample generated using the optimal preparation parameters burnt more vigorously and rapidly than raw Al and Al/Viton A. Finally, the reaction molecular dynamics simulation was employed to gain insight into the effect of Viton A on the combustion of Aluminum particles at the molecular level. • A solvent/non-solvent method was developed to prepare nano Al-based composites. • Core-shell structured Al-Viton A particles were prepared via the novel method. • The as-prepared particles presented a superior combustion performance. • The pre-ignition reaction initiated and promoted the oxidation of nano aluminum. [ABSTRACT FROM AUTHOR]

Damage of oligodendrocytes after ischemia has negative impact on white matter integrity and neuronal function. In this work, we explore whether Netrin-1 (NT-1) overexpression facilitates white matter repairing and remodeling. Adult CD-1 mice received stereotactic injection of adeno-associated virus carrying NT-1 gene (AAV-NT-1). One week after gene transfer, mice underwent 60 minutes of middle cerebral artery occlusion. The effect of NT-1 on neural function was evaluated by neurobehavioral tests. Proliferated oligodendrocyte progenitor cells (OPCs), newly matured oligodendrocytes, and remyelination were semi-quantified by immunohistochemistry. The role of NT-1 in oligodendrogenesis was further explored by examining specific NT-1 receptors and their function. Netrin-1 overexpression was detected in neurons and astrocytes 2 weeks after AAV-NT-1 gene transfer and significantly improved the neurobehavioral outcomes compared with the control (P<0.05). In comparison with the control, proliferated OPCs, newly matured oligodendrocytes, and remyelination were greatly increased in the ipsilateral hemisphere of AAV-NT-1-transduced mice. Furthermore, both NT-1 receptors deleted in colorectal carcinoma and UNC5H2 were expressed on OPCs whereas only UNC5H2 was expressed in myelinated axons. Our study indicated that NT-1 promoted OPC proliferation, differentiation, and increased remyelination, suggesting that NT-1 is a promising factor for white matter repairing and remodeling after ischemia. [ABSTRACT FROM AUTHOR]