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At present, the Synthetic Aperture Radar (SAR) image classification method based on Convolution Neural Network (CNN) has faced some problems such as poor noise resistance and generalization ability. Spiking Neural Network (SNN) is one of the core components of brain-like intelligence and has good application prospects. This article constructs a complete SAR image classifier based on unsupervised and supervised learning of SNN by using spike sequences with complex spatio-temporal information. We firstly expound on the spiking neuron model, the receptive field of SNN, and the construction of spike sequence. Then we put forward an unsupervised learning algorithm based on STDP and a supervised learning algorithm based on gradient descent in series. The average classification accuracy of single layer and bilayer unsupervised learning SNN in three categories images on MSTAR dataset is 81.1% and 82.9%, respectively. Furthermore, the convergent output spike sequences of unsupervised learning can be used as teaching signals. Based on the TensorFlow framework, a single layer supervised learning SNN is built from the bottom, and the classification accuracy reaches 90.2%. By comparing noise resistance and model parameters between SNNs and CNNs, the effectiveness and outstanding advantages of SNN are verified. Code to reproduce our experiments is available at https://github.com/Jiankun-chen/Supervised-SNN-with-GD. [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI) is distinguished by rapid and severe respiratory distress and prolonged hypoxemia. A traditional Chinese medicine (TCM), known as the Fuzhengjiedu formula (FZJDF), has been shown to have anti-inflammatory benefits in both clinical and experimental studies. The precise underlying processes, nevertheless, are yet unclear. This study sought to enlighten the protective mechanism of FZJDF in ALI through the standpoint of the gut-lung crosstalk. The impact of FZJDF on lipopolysaccharide (LPS)-induced ALI murine model were investigated, and the lung injury score, serum interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) expression were measured to confirm its anti-inflammatory effects. Additionally, gut microbiota analysis and serum and fecal samples metabolomics were performed using metagenomic sequencing and high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry, respectively. FZJDF significantly induced histopathological changes caused by LPS-induced ALI as well as downregulated the serum concentration of IL-1β and TNF-α. Furthermore, FZJDF had an effect in gut microbiota disturbances, and linear discriminant effect size analysis identified signal transduction, cell motility, and amino acid metabolism as the potential mechanisms of action in the FZJDF-treated group. Several metabolites in the LPS and FZJDF groups were distinguished by untargeted metabolomic analysis. Correlations were observed between the relative abundance of microbiota and metabolic products. Comprehensive network analysis revealed connections among lung damage, gut microbes, and metabolites. The expression of glycine, serine, glutamate, cysteine, and methionine in the lung and colon tissues was dysregulated in LPS-induced ALI, and FZJDF reversed these trends. This study revealed that FZJDF considerably protected against LPS-induced ALI in mice by regulating amino acid metabolism via the gut-microbiota-lung axis and offered thorough and in-depth knowledge of the multi-system linkages of systemic illnesses. [Display omitted] [ABSTRACT FROM AUTHOR]

Despite global warming, extreme low-temperature stress (LTS) events pose a significant threat to rice production (especially in East Asia) that can significantly impact micronutrient and heavy metal elements in rice. With two billion people worldwide facing micronutrient deficiencies (MNDs) and widespread heavy metal pollution in rice, understanding these impacts is crucial. We conducted detailed extreme LTS experiments with two rice (Oryza sativa L.) cultivars (Huaidao 5 and Nanjing 46) grown under four temperature levels (from 21/27 °C to 6/12 °C) and three LTS durations (three, six, and nine days). We observed significant interaction effects for LTS at different growth stages, durations and temperature levels on the contents and accumulation of mineral elements. The contents of most mineral elements (such Fe, Zn, As, Cu, and Cd) increased significantly under severe LTS at flowering, but decreased under LTS at the grain-filling stage. The accumulations of all mineral elements decreased at the three growth stages under LTS due to decreased grain weight. The contents and accumulation of mineral elements were more sensitive to LTS at the peak flowering stage than at the other two stages. Furthermore, the contents of most mineral elements in Nanjing 46 show larger variation under LTS compared to Huaidao 5. Accumulated cold degree days (ACDD, °C·d) were found to be suitable for quantifying the effects of LTS on the relative contents and accumulations of mineral elements. LTS at the flowering stage will help alleviate MNDs, but may also increase potential health risks from heavy metals. These results provide valuable insights for evaluating future climate change impacts on rice grain quality and potential health risks from heavy metals. [Display omitted] • LTS effects on mineral elements depend on growth stages, LTS durations and levels. • LTS at flowering will alleviate the MNDs, but also increased heavy metals content. • ACDD quantified the LTS effect on content and accumulation of mineral elements well. • LTS effects on mineral elements at early flowering stage was more sensitive than other treatment stages. [ABSTRACT FROM AUTHOR]

Si with x = 0.000, 0.015, 0.030, and 0.050 is successfully doped into layered LiNi 0.5 Mn 0.5-x Si x O 2 using a sol − gel method. Si doping results in a decrease in lattice constant, Li/Ni mixing, stress, and size of primary particles. Si is distributed at the Mn site probably nonuniformly to cause two different states of Si 4+ . Si doping exerts no influence on the 2p bands of Ni 2+ , and however gives rise to a slight splitting of 2p 3/2 band of Mn 4+ , and tends to increase the diffusion activation energy of Li + . The optimum performance is achieved for LiNi 0.5 Mn 0.5-x Si x O 2 with x = 0.015 which has the highest BET surface area. Detailed analysis of structural modifications allows one to conclude that the remarkable alleviation of agglomeration of primary particles other than the optimization of structure related parameters such as the lattice constant, metal − oxygen bond length, ordering, cation mixing, size, and stress is responsible predominantly for the performance improvement. This study suggests that silicon is not an effective dopant for performance improvement of layered LiMO 2 simply from the perspective of structural modifications and optimization. [ABSTRACT FROM AUTHOR]

Highlights • The synergistic effects of multiple factors on SBD-AD were studied herein. • Attractive regulating strategies were developed based on feedstock ratio data. • The rate-limiting step in SBD-AD methane production is a low ammonia nitrogen level. • Comprehensive methane metabolic pathways are important for optimizing SBD-AD. • Significant differences in the microbial community were induced by feedstock type. Abstract This study investigated the synergistic effects and regulation strategy of multiple factors for improving methane production in sequencing batch dry anaerobic digestion (SBD-AD) using corn stalks (CS) and cow dung (CD). The regulation of the spray frequency (SF) and inoculum content (IC) significantly improved methane yield, which increased feedstock ratios (FRs) by 12.4–121.3%. Moreover, the relationship between SF and IC produced distinct interaction modes. An FR of 4:6 increased the SF to 2 h for the CD-rich condition, and an FR of 6:4 decreased the SF during a 6 h interval and increased the IC for the CS-rich condition, resulting in increases in methane yield and the conversion efficiency of volatile fatty acids (VFAs). Methanogenesis (Methanogens) played a key role in SBD-AD. The nutrient substrate (NH 4 -N+) and key enzyme activities of methanogens were significantly affected such that the synergistic effect of the acetoclastic and hydrogenotrophic methanogenesis pathways was likely strengthened. [ABSTRACT FROM AUTHOR]

LiFe x Mn 2-x O 4 ( x = 0.0, 0.1 and 0.2) with superior rate and cycling performance is synthesized using a sol – gel method by combining citric acid and glucose as the chelating agent. For the first time Fe is found to basically occupy the 16d site. Fe doping decreases the occupancies of Mn at the 8a site considerably, and reduces the variations of the lattice volume before and after charge significantly, and suppresses the formation of the lower valence manganese surface phases. The structure - related factors other than the conventional morphology and size lead to the drastically enhanced performance of the Fe - doped samples. The combination of the decreased occupancies of Mn on the 8a site, and the only occupation of Fe on the 16d site, and the suppression of the surface phases of manganese ions with the lower valences and the alleviation of the Jahn - Teller effect due to the partial replacement of Mn 3+ by Fe 3+ result in both the improved electronic and ionic conductivities, and thus the drastically enhanced performance. The capacity of 66 mAh g −1 for x = 0.2 is delivered for 300C discharge with 1C charge. The capacity retentions after 1500 cycles for 100C discharge and 10C charge at room temperature (RT) and 60°C are 90% and 83%, respectively. The present study opens a feasible way to obtain the high performance manganese spinel cathode by controlling the lattice site occupation of an alien element and manganese and the formation of low valence manganese surface phases. [ABSTRACT FROM AUTHOR]

[Display omitted] • Established a high lignocellulosic dry-wet combined anaerobic digestion system. • The kinetic parameters of the whole anaerobic digestion process were revealed. • Synergism between Clostridiales and methanogens was evaluated via network analysis. • Syntrophy between SFOB and methylotrophic Methanospirillum was observed. • The number of key acidogenic Clostridium was increased by 80.77–107.11%. Dry-wet combined anaerobic digestion is a novel approach for treating lignocellulosic waste by increasing the organic load of reactor while accelerating the conversion of organic acids. Here, we investigated the effect of regulated substrate ratios and initial pH in the dry acidogenesis stage on the bioconversion efficiency of dry-wet combined anaerobic digestion. Our data revealed microbial interactions and further identified key microbes based on microbial co-occurrence network analysis. On day three of acidification, the kinetic hydrolysis rate and acidification yield reached 1.66 and 60.07%, respectively; this was attributed to enhancement of the synergistic effect between Clostridiales and Methanosaeta , which increased the proportion of corn straw in the substrate or lowered the initial spray slurry pH to 5.5–6.5. With increased acidification capacity, acetoclastic methanogens were enriched in the wet methanogenesis stage; the syntrophic effect of Syntrophomonadales , Syntrophobacterales and Methanospirillum , meanwhile, was enhanced, leading to an overall improvement in biogas production. [ABSTRACT FROM AUTHOR]

• Cottonwood biochar was used as an enhanced mediator for the CSTR-AD of cornstalk. • The highest volumetric biogas production rate with biochar was 1.40 L/L/d. • The CO 2 content decreased by 5.90% while the CH 4 content increased by 7.40%. • Microbial abundance had positive correlations with the environmental parameters. The composition of biogas produced by anaerobic digestion (AD) is typically not ideal due to high CO 2 content. In the study, cottonwood biochar was used as an enhanced mediator for the continuously stirred tank reactor AD of cornstalk. The effects of substrate loading and biochar dosage on biogas composition, volatile fatty acids (VFAs), NH 3 -N, and microbial community characteristics were systematically explored. The results showed that the highest volumetric biogas production rate with biochar was 1.40 L/L/d, at the same time, the CO 2 content in the biogas decreased by 5.90%, while the CH 4 content increased by 7.40%, compared with the values in AD without biochar. Moreover, VFAs were degraded effectively, in particular, the propionic acid concentration decreased by 55.7%. Besides, microbial abundance had positive correlations with environmental parameters. This study could provide valuable information for both the elucidation of strengthening mechanisms of biochar and further large-scale engineering application. [ABSTRACT FROM AUTHOR]