Modeling, analysis, and numerical approximations of the forced Fisher\u27s equation and related control problems

The Fisher equation with inhomogeneous forcing is considered in this work. First, a forced Fisher equation and boundary conditions are derived. Then, the existence of a local and global solution for the forced equation with a homogeneous Dirichlet condition is proved and the results are generalized to the case of less regular forces. Semi-discrete finite element approximations, semi-discrete approximations in the time variable, and fully discrete approximations are studied under certain minimal regularity assumptions. Numerical experiments are carried out and computational results are presented. An optimal distributed control problem related to the forced Fisher equation is also considered, the optimality system is derived, and numerical approximations of the optimality system are discussed

Bacterial community composition in reclaimed and unreclaimed tailings of Dexing copper mine, China

An investigation was conducted to compare the microbial community structures between contaminated and reclaimed mine tailings of Dexing copper mine, Jiangxi province, China. Sample T1 was obtained from tailings site, where reclamation of phytostabilization has been conducted for 20 years successfully whereas, the other one (sample T4) was obtained from the unreclaimed tailings site. Physico-chemical characteristics, chemical speciation of heavy metals Cu, Cd and Zn were revealed to compare the effects of reclamation. A polymerase chain reaction (PCR)-based cloning approach was employed to investigate the bacterial community composition in these two samples. Results indicate the improved physico-chemical conditions and decreased bioavailability of heavy metals Cd and Zn significantly in the sample collected from reclaimed site compared with the other unreclaimed mine tailings site. Phylogenetic analysis indicated that bacteria in these two samples fell into 12 putative phylogenetic divisions. Sample T1 had 12 phyla were present, and the community was predominated by Planctomycetes (20%), α-proteobacteria (16%), Chloroflexi (12%) and Acidobacteria (10%). On the other hand, sample T4 had only 4 phyla and was predominated by y-proteobacteria (86%). The diversity of microbes in sample T1 significantly increased when compared with sample T4. The structure of microbial community composition in the first sample also was optimized to sustain more phyla associated with a healthier soil after reclamation. From the results, it could be deduced that the inventories of bacterial populations such as Planctomycetes, Chloroflexi, α-proteobacteria, Acidobacteria and Actinobacteria predominated in sample T1, but were essentially absent in sample T4. This may serve as potential bioindicator for the reclamation evaluation of tailings.Keywords: Mine tailings, reclamation, bacterial community composition, bioindicatorsAfrican Journal of Biotechnology Vol. 12(30), pp. 4841-484

An unsupervised domain adaptation method towards multi-level features and decision boundaries for cross-scene hyperspectral image classification.

Despite success in the same-scene hyperspectral image classification (HSIC), for the cross-scene classification, samples between source and target scenes are not drawn from the independent and identical distribution, resulting in significant performance degradation. To tackle this issue, a novel unsupervised domain adaptation (UDA) framework toward multilevel features and decision boundaries (ToMF-B) is proposed for the cross-scene HSIC, which can align task-related features and learn task-specific decision boundaries in parallel. Based on the maximum classifier discrepancy, a two-stage alignment scheme is proposed to bridge the interdomain gap and generate discriminative decision boundaries. In addition, to fully learn task-related and domain-confusing features, a convolutional neural network (CNN) and Transformer-based multilevel features extractor (generator) is developed to enrich the feature representation of two domains. Furthermore, to alleviate the harm even the negative transfer to UDA caused by task-irrelevant features, a task-oriented feature decomposition method is leveraged to enhance the task-related features while suppressing task-irrelevant features, and enabling the aligned domain-invariant features can be contributed to the classification task explicitly. Extensive experiments on three cross-scene HSI benchmarks have validated the effectiveness of the proposed framework

Diazotrophic community in the sediments of Poyang Lake in response to water level fluctuations

Water level fluctuations (WLFs) are typical characteristic of floodplain lakes and dominant forces regulating the structure and function of lacustrine ecosystems. The sediment diazotrophs play important roles in contributing bioavailable nitrogen to the aquatic environment. However, the relationship between the diazotrophic community and WLFs in floodplain lakes is unknown. In this paper, we carried out a comprehensive investigation on the alpha diversity, abundance, composition and co-occurrence network of the sediment diazotrophs during different water level phases in Poyang Lake. There were no regular variation patterns in the alpha diversity and abundance of the sediment diazotrophs with the water level phase transitions. The relative abundance of some diazotrophic phyla (including Alphaproteobacteria, Deltaproteobacteri, Euryarchaeota, and Firmicutes) and genera (including Geobacter, Deferrisoma, Desulfuromonas, Rivicola, Paraburkholderia, Methylophilus, Methanothrix, Methanobacterium, and Clostridium) was found to change with the water level phase transitions. The results of ANOSIM, PerMANOVA, and DCA at the OTU level showed that the diazotrophic community structure in the low water level phase was significantly different from that in the two high water level phases, while there was no significant difference between the two high water level phases. These results indicated that the diazotrophic community was affected by the declining water level in terms of the composition, while the rising water level contributed to the recoveries of the diazotrophic community. The diazotrophs co-occurrence network was disrupted by the declining water level, but it was strengthened by the rising water level. Moreover, redundancy analysis showed that the variation of the diazotrophic community composition was mostly related to sediment total nitrogen (TN) and total phosphorous (TP). Interestingly, the levels of sediment TN and TP were also found to vary with the water level phase transitions. Therefore, it might be speculated that the WLFs may influence the sediment TN and TP, and in turn influence the diazotrophic community composition. These data can contribute to broadening our understanding of the ecological impacts of WLFs and the nitrogen fixation process in floodplain lakes

The diagnostic significance of the ZNF gene family in pancreatic cancer: a bioinformatics and experimental study

Background: Pancreatic adenocarcinoma (PAAD) is among the most devastating of all cancers with a poor survival rate. Therefore, we established a zinc finger (ZNF) protein-based prognostic prediction model for PAAD patients.Methods: The RNA–seq data for PAAD were downloaded from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. Differentially expressed ZNF protein genes (DE-ZNFs) in PAAD and normal control tissues were screened using the “lemma” package in R. An optimal risk model and an independent prognostic value were established by univariate and multivariate Cox regression analyses. Survival analyses were performed to assess the prognostic ability of the model.Results: We constructed a ZNF family genes-related risk score model that is based on the 10 DE-ZNFs (ZNF185, PRKCI, RTP4, SERTAD2, DEF8, ZMAT1, SP110, U2AF1L4, CXXC1, and RMND5B). The risk score was found to be a significant independent prognostic factor for PAAD patients. Seven significantly differentially expressed immune cells were identified between the high- and low-risk patients. Then, based on the prognostic genes, we constructed a ceRNA regulatory network that includes 5 prognostic genes, 7 miRNAs and 35 lncRNAs. Expression analysis showed ZNF185, PRKCI and RTP4 were significantly upregulated, while ZMAT1 and CXXC1 were significantly downregulated in the PAAD samples in all TCGA - PAAD, GSE28735 and GSE15471 datasets. Moreover, the upregulation of RTP4, SERTAD2, and SP110 were verified by the cell experiments.Conclusion: We established and validated a novel, Zinc finger protein family - related prognostic risk model for patients with PAAD, that has the potential to inform patient management

Chloridobis(1,10-phenanthroline)zinc(II) tetra­chlorido(1,10-phenan­throline)bis­muthate(III) monohydrate

In the crystal structure of the title monohydrate salt, [ZnCl(C12H8N2)2][BiCl4(C12H8N2)]·H2O, the ionic components are linked into three-dimensional supra­molecular channels by five pairs of C—H⋯Cl hydrogen bonds and π–π stacking inter­actions with an inter­planar distance of 3.643 (2) Å. The solvent water mol­ecules are lodged in the channels