UNIMEMnet: Learning long-term motion and appearance dynamics for video prediction with a unified memory network.

As a pixel-wise dense forecast task, video prediction is challenging due to its high computation complexity, dramatic future uncertainty, and extremely complicated spatial-temporal patterns. Many deep learning methods are proposed for the task, which bring up significant improvements. However, they focus on modeling short-term spatial-temporal dynamics and fail to sufficiently exploit long-term ones. As a result, the methods tend to deliver unsatisfactory performance for a long-term forecast requirement. In this article, we propose a novel unified memory network (UNIMEMnet) for long-term video prediction, which can effectively exploit long-term motion-appearance dynamics and unify the short-term spatial-temporal dynamics and long-term ones in an architecture. In the UNIMEMnet, a dual branch multi-scale memory module is carefully designed to extract and preserve long-term spatial-temporal patterns. In addition, a short-term spatial-temporal dynamics module and an alignment and fusion module are devised to capture and coordinate short-term motion-appearance dynamics with long-term ones from our designed memory module. Extensive experiments on five video prediction datasets from both synthetic and real-world scenarios are conducted, which validate the effectiveness and superiority of our proposed method UNIMEMnet over state-of-the-art methods.

Functional organic fertilizers can alleviate tobacco (Nicotiana tabacum L.) continuous cropping obstacle via ameliorating soil physicochemical properties and bacterial community structure.

Continuous cropping obstacle (CCO) in tobacco is a prevalent and intractable issue and has not yet been effectively solved. Many researchers have favored exploring environmentally friendly and sustainable solutions to CCO (e.g, the application of (bio-) organic fertilizers). Therefore, to study the effects of functional organic fertilizers (FOFs) on tobacco CCO, we applied five types of fertilizers in a tobacco continuous cropping field with red soil (i.e., CF: tobacco-special chemical fertilizers; VOF: vermicompost-based FOF; HOF: humic acid-based FOF; WOF: wood biochar-based FOF; COF: compound FOF). The tobacco plant agronomic traits, leaf yield, economic value, and chemical quality (nicotine, total sugar, K2O, Cl contents, etc.) were evaluated via the continuous flow method. Meanwhile, we determined rhizosphere soil physicochemical properties, phenolic acids content, and bacterial community diversity by high-throughput sequencing. The results show that FOFs improved the tobacco plant agronomic traits, leaf yield (by 2.9-42.8%), value (by 1.2-47.4%), and chemical quality when compared with CF. More content of NH4 +-N, available P, and available K were discovered in the rhizosphere soil in VOF, HOF, and WOF. The rhizosphere sinapic acid and total phenolic acids content declined in the FOF treatments (1.23-1.56 and 7.95-8.43 mg kg-1 dry soil, respectively) versus those in the CF treatment (2.01 and 10.10 mg kg-1 dry soil, respectively). Moreover, the rhizosphere bacterial community structure changed under FOF functions: the beneficial microbes Actinobacteria, Firmicutes, Streptomyces, and Bacillus increased, and the harmful microbes Acidobacteria and Gemmatimonadota decreased in abundance. There was a positive correlation between the tobacco leaf yield and soil NH4 +-N, TC content, and the relative abundance of Proteobacteria and Actinobacteriota. In summary, the application of VOF and WOF is a modest, practical, and environmentally friendly strategy to alleviate tobacco CCO from the standpoint of recycling solid waste.

Synthesis of acidified magnetic sludge-biochar and its role in ammonium nitrogen removal: Perception on effect and mechanism.

An acidified magnetic sludge-biochar (MSB) was prepared to enhance ammonium nitrogen (AN) removal efficiency in eutrophic water, and MSB was obtained by secondary pyrolysis of sludge biochar powder. A series of MSB were prepared under 300, 400, 500, 600 °C and different valence states of iron ions by impregnation pyrolysis, which is based on the deposition of unstable iron minerals on biochar matrix. Physicochemical properties of pristine biochar and MSB were revealed through characterization analysis, suggesting that MSB prepared by ferric chloride at 400 °C presented the largest adsorption capacity, and the acid-modification enhanced the ammonium adsorption capacity by 10.7%. Electrostatic attraction and ion-exchange processes were identified as the main adsorption mechanisms of MSB on AN. As the most dominant mechanism, ion exchange of AN with functional groups containing -OH and CO on the surface of MSB resulted in the relative content of -OH (61.3%) and CO (11.5%) bonds reduced to 34.2% and 7.0% respectively. The novel magnetic sludge-biochar with acid-modification possessed enhanced electron transfer capacity, revealing a removal pathway of ammonium by nitrification. The findings above demonstrated that MSB is a promising adsorbent for ammonium removal and can be applied to the natural nitrogen-rich water regulation.

Succession Pattern in Soil Micro-Ecology Under Tobacco (Nicotiana tabacum L.) Continuous Cropping Circumstances in Yunnan Province of Southwest China.

Continuous cropping obstacle (CCO) is a common phenomenon in agricultural production and extremely threatens the sustainable development of agriculture. To clarify the potential keystone factors causing tobacco (Nicotiana tabacum L.) CCO, tobacco plants, topsoil, and rhizosphere soil were sampled from the fields with no, slight, and severe tobacco disease in Dali and Yuxi of Yunnan province in China. The physicochemical properties of topsoil and rhizosphere soil, the phenolic acids (PAs) contents in rhizosphere soil, and elemental contents in topsoil, rhizosphere soil, and tobacco plants were analyzed. Microbial diversity in rhizosphere soil was determined by the metagenomic sequencing method. The results showed that soil pH, texture, cation exchange capacity, organic matter, TC, TN, and available K contents showed a significant difference (p < 0.05) in soil physicochemical properties. There was a deficiency of B, K, Mg, and Mn contents in soil and/or tobacco plants. The contents of PAs, especially syringic acid in rhizosphere soil, varied significantly among the three sampling groups (p < 0.05). Meanwhile, microbial communities and functional genes changed from beneficial to harmful, showing an intimate correlation with soil pH and syringic acid content. It can be concluded that tobacco CCO could be allocated to the imbalance of soil micro-ecology, which possessed a regional feature at the two sampling sites.

Corrigendum: Tobacco Rotated with Rapeseed for Soil-Borne Phytophthora Pathogen Biocontrol: Mediated by Rapeseed Root Exudates.

[This corrects the article on p. 894 in vol. 7, PMID: 27379037.].

Tobacco Rotated with Rapeseed for Soil-Borne Phytophthora Pathogen Biocontrol: Mediated by Rapeseed Root Exudates.

Black shank, caused by Phytophthora parasitica var. nicotianae, is a widespread and destructive disease of tobacco. Crop rotation is essential in controlling black shank. Here, we confirmed that rotating black shank-infested fields with rapeseed (Brassica napus) suppressed the incidence this disease. Further study demonstrated that rapeseed roots have a strong ability to attract zoospores and subsequently stop the swimming of zoospores into cystospores. Then, rapeseed roots secrete a series of antimicrobial compounds, including 2-butenoic acid, benzothiazole, 2-(methylthio)benzothiazole, 1-(4-ethylphenyl)-ethanone, and 4-methoxyindole, to inhibit the cystospore germination and mycelial growth of P. parasitica var. nicotianae. Thus, rapeseed rotated with tobacco suppresses tobacco black shank disease through the chemical weapons secreted by rapeseed roots.