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This study presents a review of the effect of nano-additives in improving the mechanical properties of composites. Nano-additives added to composites, also termed nanocomposites, have promising applications in aerospace, medical, biomedical, automotive, and military. The nanoparticles alter either the surface, bulk, or both, depending upon the process, and dramatically change the thermal conductivity, tensile strength, flexural strength, fatigue strength, impact resistance, vibration resistance, buckling, post-buckling, nanoparticles surface modification, and application of machine learning as well as optimization methods in nanocomposite materials. Such transformations in composite materials are extensively studied by researchers and positive implications are successfully deployed in various applications. Interestingly, the recent findings revealed that the weak chemical bonding between the fiber and matrix phase is the main reason for delamination, however, by the addition of nanoparticles, the chances of delamination are reduced even under excessive loading. Graphene and multi-walled carbon nanotubes (MWCNTs) are the most excessively reported nanomaterials for enhancing the vibration behavior and energy absorption capacity, as well as decreasing the adverse effects due to porosity within the composite structure. Also, machine learning techniques showed to be a promising way to further improve the mechanical properties while reducing the total cost of the fabrication process by predicting and providing optimum fabrication characteristics with acceptable accuracy compared to realistic conditions.

The reduction of both energy consumption and production/maintenance costs in the industry requires the use of advanced engineering materials with remarkable features, including lightweight and long-term service life. As one of the advanced engineering materials, composites are widely applied in industry and civilian daily life. Nevertheless, there are some mechanical factors such as tensile strength restricting the application of such a material. To this end, this study is aimed to comprehensively review the recent research on the effects of fabrication characteristics on the tensile resistance of GFRP, CFRP, and AFRP composites. As revealed by recent progress, the epoxy resin is an advisable option for the production of high-performance polymeric composites due to the remarkable tensility, compression, and corrosion resistance. However, the high cost of epoxy resin is not favorable for mass production. In hybrid composites, stacking sequence is a vital factor that determines the ultimate tensile strength. In terms of higher mechanical performance, some researchers suggested using Kevlar fibers with woven orientation alongside the Carbon as axial fibers. At the same time, it is essential to carefully establish the value of fiber volume fraction. Otherwise, this can lead to dramatic internal defects such as agglomeration. In general, this review article was performed to investigate the impacts of composite fabrication characteristics such as fabrication method, reinforcing fibers orientation, fiber type, matrix phase type, and volume fraction of reinforcing phase on the tensile properties of composites used in aerospace, military, civil constructions, and automotive applications. In addition, the authors tried their best to make this research a credible source in the field of mechanical properties of CFRP, GFRP, and AFRP composites for future studies of other researchers.

Abstract The three‐dimensional computerized ionospheric tomography (3DCIT) technique that fused multisource data is used to reconstruct the spatial distribution of tongue of ionization (TOI) appeared over Greenland during a moderate geomagnetic storm on 11 October 2010. The reconstruction results are validated with observations from the constellation observing system for meteorology, ionosphere, and climate radio occultations and two ionosonde stations, which show good agreements. The 3DCIT images indicated a zone of high electron density (magnitude of ∼5 TECU) that crossed northern Greenland and electrons were input into the polar region in the anti‐sunward direction after aggregating at midlatitudes, which formed a TOI. The images also revealed that the TOI magnitude was larger in the upper ionosphere ssand lower at 300 and 500 km but still noticeable. Below 300 km, the TOI was difficult to detect. The simulation result of the Thermosphere‐Ionosphere‐Electrodynamic General Circulation Model (TIEGCM) also showed the same TOI structure. Then, we combined the measured ionospheric data and term‐by‐term analysis of the ion continuity formula in TIEGCM to further identify the principal TOI formation mechanisms. We assume that the dominant TOI formation mechanism is electric field transport, which is offset by ambipolar diffusion and neutral wind transport. Furthermore, the uplift of electrons and the insignificant effect of other physical processes explained the insignificant TOI in lower ionosphere.

The stability, geometry, microstructure, and specie combination together with the electronic states of the anatase TiO2 with oxygen defect content of 0%, 3.125%, 6.25%, and 12.5% have been intensively studied within the framework of the density functional theory method. The results show that the TiO2 with an oxygen defect is not as stable as intrinsic TiO2. The compound formation enthalpy Ef and the oxygen defect formation energy value tend to be larger for a higher defect content, and the oxygen defect gets harder to be formed. The bonds within the TiO6 polyhedron are different and not geometrically symmetrical. The bond strengths show distinct diversity, and the primitive cell of anatase TiO2 show spatial expansion when there are oxygen defects. All bands moved down to the low energy region, and two impurity energy band levels emerged for the anatase TiO2 with oxygen defect. The energy band gap is decreased from 3.085 eV to 1.165 eV, 1.0015 eV, and 0.43 eV. There are generally 7 peaks for the spin density of states function, corresponding to their 5 main bands. For the anatase TiO2 with an oxygen defect content of 12.5%, the spin density of states functions are not horizontal ordinate symmetrical near −1.12 eV and 0.31 eV. They are formed by oxygen defect energy levels, which is the result of the Ti d and O p state electron polarization. Transitions from weak paramagnetic to antiferromagnetic are found for the anatase TiO2 with oxygen defect.

Error source analyses are critical for the satellite-retrieved surface net radiation (Rn) products. In this study, we evaluate the Rn error sources in the Clouds and the Earth’s Radiant Energy System (CERES) project at 43 sites from July in 2007 to December in 2007 in China. The results show that cloud fraction (CF), land surface temperature (LST), atmospheric temperature (AT) and algorithm error dominate the Rn error, with error contributions of ~-20, ~15, ~10 and ~10 W/m2 (net shortwave (NSW)/longwave (NLW) radiation), respectively. For NSW, the dominant error source is algorithm error (more than 10 W/m2), particularly in spring and summer with abundant cloud. For NLW, due to the high sensitivity of algorithm and large LST/CF error, LST and CF are the largest error sources, especially in northern China. The AT influences the NLW error large in southern China because of the large AT error in there. The total precipitable water has weak influence on Rn error even with the high sensitivity of algorithm. In order to improve Rn quality, CF and LST (AT) error in northern (southern) China should be decreased.

The aim of the present study was to determine whether dietary Bacillus subtilis natto could affect growth performance of Muscovy ducks. A total of 120 hundred Muscovy ducks at the age of 1 day were randomly assigned to four groups (30 Muscovy ducks/group), and fed with diets supplemented with 0% (control group), 0.1%, 0.2%, and 0.4% Bacillus subtilis natto, respectively during the 6-week feeding period. Weight gain, feed intake and feed conversion efficiency of Muscovy ducks were significantly improved by the dietary addition of Bacillus subtilis natto, and the results were more significant in 0.4% dietary Bacillus subtilis natto treatment group; Also, Bacillus subtilis natto reduced Escherichia coli and Salmonella colonies, and increased lactobacilli population in the ileum and the cecum. Biochemical parameters, including total protein, GOT (glutamic oxaloacetic transaminase), GPT (glutamic pyruvic transaminase), AKP (alkaline phosphatase), triiodothyronine (T3) and tetraiodothyronine (T4) contents (pBacillus subtilis natto was added to the diets (p0.05). The results of the present study indicate that diets with 0.4% Bacillus subtilis natto improved the growth performance of Muscovy ducks by increasing the absorption of protein, simulating hormone secretion, suppressing harmful microflora, and improving the duodenal structure and immune functions of Muscovy ducks. It is suggested that Bacillus subtilis natto is a potential candidate to be used use as a probiotic to improve the growth performance of Muscovy ducks.

Acyl carrier protein (ACP), as an essential protein cofactor, plays an important role in de novo synthesis of fatty acids in plastids. In this study, the expression profile of peanut (Arachis hypogaea) AhACP1-1 and AhACP1-2 was analyzed in different tissues. The expression level of AhACP1-1 was highest in the seed, whereas expression was barely detected in the shoot, and AhACP1-2 was expressed in every tissue analyzed with the highest expression level detected in the leaf and seed. Overexpression (OE) and antisense-inhibition (AT) of AhACP1 in transgenic tobacco modified the transcript level of endogenous NtACPs, and the content of total lipids and composition of fatty acid in leaves were altered compared with the wild-type control. Transgenic OE-AhACP1 or AT-AhACP1 tobacco exhibited a significant increase or decrease in polyunsaturated C18:2 and C18:3 fatty acid content, and were more tolerant or sensitive to cold stress, respectively. It is suggested that AhACP1 bound with C18:1 might be the specific substrate of oleoyl-ACP thioesterase or glycerol-3-phosphate acyltransferase, and participates in membrane lipid synthesis.

(+)-2-(1-hydroxyl-4-oxocyclohexyl) ethyl caffeate (HOEC) was isolated from Incarvillea mairei var. granditlora (Wehrhahn) Grierson. The plants of the Incarvillea genus have long been used as folk medicines for the treatment of inflammation-related diseases in China. 5-Lipoxygenase (5-LOX), a key enzyme in the arachidonic acid (AA) cascade, was identified as a potential target of HOEC by a pulldown assay, and then extensively validated by biosensor-based affinity detection, enzyme-based activity assays, cell-based AA metabolite analysis and computer-aided AA network simulation. Further in vivo studies of AA-induced ear oedema, ovalbumin (OVA)-induced lung inflammation and collagen-induced arthritis demonstrated the anti-inflammatory potency and validated the therapeutic target of HOEC. This work revealed that HOEC acted as an anti-inflammatory agent targeting 5-LOX, which not only confirmed the key role of 5-LOX in inflammation but also provided a paradigm for the exploration of natural product mechanisms of action.

(+)-2-(l-hydroxyl-4-oxocyclohexyl) ethyl caffeate (HOEC) was isolated from Incarvillea mairei var. grandiflora (Wehrhahn) Grierson. The plants of the Incarvillea genus have long been used as folk medicines for the treatment of inflammation-related diseases in China. 5-Lipoxygenase (5-LOX), a key enzyme in the arachidonic acid (AA) cascade, was identified as a potential target of HOEC by a pulldown assay, and then extensively validated by biosensor-based affinity detection, enzyme-based activity assays, cell-based AA metabolite analysis and computer-aided AA network simulation. Further in vivo studies of AA-induced ear oedema, ovalbumin (OVA)-induced lung inflammation and collagen-induced arthritis demonstrated the anti-inflammatory potency and validated the therapeutic target of HOEC. This work revealed that HOEC acted as an anti-inflammatory agent targeting 5-LOX, which not only confirmed the key role of 5-LOX in inflammation but also provided a paradigm for the exploration of natural product mechanisms of action. [ABSTRACT FROM AUTHOR]

Permanent scatterers differential interferometric synthetic aperture radar (PS-DInSAR) is a technique for detecting surface micro-deformation, with an accuracy at the centimeter to millimeter level. However, its performance is limited by the number of SAR images available (normally more than 20 are needed). Compressive sensing (CS) has been proven to be an effective signal recovery method with only a very limited number of measurements. Applying CS to PS-DInSAR, a novel CS-PS-DInSAR method is proposed to estimate the deformation with fewer SAR images. By analyzing the PS-DInSAR process in detail, first the sparsity representation of deformation velocity difference is obtained; then, the mathematical model of CS-PS-DInSAR is derived and the restricted isometry property (RIP) of the measurement matrix is discussed to validate the proposed CS-PS-DInSAR in theory. The implementation of CS-PS-DInSAR is achieved by employing basis pursuit algorithms to estimate the deformation velocity. With the proposed method, DInSAR deformation estimation can be achieved by a much smaller number of SAR images, as demonstrated by simulation results. [ABSTRACT FROM AUTHOR]

Active student responding is often required to remedy computation skill deficits in students with learning disabilities. However, these students may find computation assignments unrewarding and frustrating, and be less likely to choose to engage in assigned computation tasks. In the current study, middle school students with learning disabilities worked on control assignments containing 15 four-digit minus four-digit target computation problems and interspersal assignments containing 15 similar problems and five additional one-digit minus one-digit problems. Results showed that interspersing the brief problems did not reduce target problem accuracy levels or opportunities to respond to target problems. Students did complete more total problems (i.e., target and single-digit problems) on the interspersal assignment. Even though the interspersal assignment contained more work, significantly more students rated it as requiring less effort to complete and selected it for homework. Discussion focuses on applied implications, causal mechanisms, and future research related to the interspersal procedure and the discrete task completion hypothesis. [ABSTRACT FROM AUTHOR]