Utilization of single-chamber microbial fuel cells as renewable power sources for electrochemical degradation of nitrogen-containing organic compounds

By employing promising single-chamber microbial fuel cells (MFCs) as renewable power sources, an aerated electrochemical system is proposed and for nitrogen-containing organic compounds (pyridine and methyl orange) removals. Carbon felt performed the best as electrode material while lower initial contaminant concentration and lower initial pH value could improve the performance. A degradation efficiency of 82.9% for pyridine was achieved after 360 min electrolysis with its initial concentration of 200 mg/L, initial pH of 3.0 and applied voltage of 700 mV. Mechanisms study implied that indirect electrochemical oxidation by generated hydrogen peroxide was responsible for their degradation. This study provides an alternative utilization form of low bioelectricity from MFCs and reveals that applying it to electrochemical process is highly-efficient as well as cost-effective for degradation of nitrogen-containing organic compounds. (C) 2015 Elsevier B.V. All rights reserved.National Natural Science Foundation of China (NSFC) [21307117, 41440025]; Research Fund for the Doctoral Program of Higher Education of China [20120022120005]; Beijing Excellent Talent Training Project [2013D009015000003]; Beijing Higher Education Young Elite Teacher Project [YETP0657]; Fundamental Research Funds for the Central Universities [2652015226, 2652015131]SCI(E)[email protected]

How to Retain the Nostalgia in Rural Tourism

Combined with the nostalgia generated in the urbanization and rapidly developing rural tourism in China, this paper firstly analyzed main reasons for generation of nostalgia, summarized prevailing problems in the development of rural tourism, and finally discussed how to retain the nostalgia in rural tourism

The auxin signaling pathway contributes to phosphorus-mediated zinc homeostasis in maize

Abstract Although the interaction between P and Zn has long been recognized in plants, the physiological and molecular mechanisms underlying P and Zn interactions are poorly understood. We show here that P supply decreases the Zn concentration in maize shoots and roots. Compared to +P + Zn (addition of both P and Zn), +P-Zn reduced and -P-Zn increased the total length of 1° lateral roots (LRs). Under +P + Zn, both P and Zn concentrations were lower in the sl1 mutant roots than in wild-type (WT) maize roots, and P accumulation did not reduce the Zn concentration in ll1 mutant roots. Transcriptome profiling showed that the auxin signaling pathway contributed to P-mediated Zn homeostasis in maize. Auxin production and distribution were altered by changes in P and Zn supply. Cytosolic Zn co-localized with auxin accumulation under +P + Zn. Exogenous application of 1-NAA and L-Kyn altered the P-mediated root system architecture (RSA) under Zn deficiency. -P-Zn repressed the expression of miR167. Overexpression of ZmMIR167b increased the lengths of 1° LRs and the concentrations of P and Zn in maize. These results indicate that auxin-dependent RSA is important for P-mediated Zn homeostasis in maize. Highlight Auxin-dependent RSA is important for P-mediated Zn homeostasis in maize

Dentate granule cells form hilar basal dendrites in a rat model of hypoxia-ischemia.

Hilar basal dendrites form on dentate granule cells following seizures. To determine whether other brain insults cause the formation of hilar basal dendrites, a model of global cerebral hypoxia/ischemia was used. Rats underwent a transient induction of ischemia by occlusion of both common carotid arteries followed by reperfusion. Hippocampal slices were prepared from these animals 1 month after the ischemic insult, and granule cells were labeled with a retrograde tracing technique after biocytin injections into stratum lucidum of CA3b. Ischemic rats had numerous biocytin-labeled granule cells with hilar basal dendrites located at the hilar border of the granule cell layer. Quantitative analysis of ischemic rats compared to controls showed a significant increase in the percentage of biocytin-labeled granule cells with hilar basal dendrites. These data demonstrate that other brain insults in addition to epilepsy may result in the formation of hilar basal dendrites on granule cells

Dentate granule cells form hilar basal dendrites in a rat model of hypoxia-ischemia.

Hilar basal dendrites form on dentate granule cells following seizures. To determine whether other brain insults cause the formation of hilar basal dendrites, a model of global cerebral hypoxia/ischemia was used. Rats underwent a transient induction of ischemia by occlusion of both common carotid arteries followed by reperfusion. Hippocampal slices were prepared from these animals 1 month after the ischemic insult, and granule cells were labeled with a retrograde tracing technique after biocytin injections into stratum lucidum of CA3b. Ischemic rats had numerous biocytin-labeled granule cells with hilar basal dendrites located at the hilar border of the granule cell layer. Quantitative analysis of ischemic rats compared to controls showed a significant increase in the percentage of biocytin-labeled granule cells with hilar basal dendrites. These data demonstrate that other brain insults in addition to epilepsy may result in the formation of hilar basal dendrites on granule cells

Tunable Ultrasmall Visible-to-Extended Near-Infrared Emitting Silver Sulfide Quantum Dots for Integrin-Targeted Cancer Imaging

The large size of many near-infrared (NIR) fluorescent nanoparticles prevents rapid extravasation from blood vessels and subsequent diffusion to tumors. This confines <i>in vivo</i> uptake to the peritumoral space and results in high liver retention. In this study, we developed a viscosity modulated approach to synthesize ultrasmall silver sulfide quantum dots (QDs) with distinct tunable light emission from 500 to 1200 nm and a QD core diameter between 1.5 and 9 nm. Conjugation of a tumor-avid cyclic pentapeptide (Arg-Gly-Asp-DPhe-Lys) resulted in monodisperse, water-soluble QDs (hydrodynamic diameter < 10 nm) without loss of the peptide’s high binding affinity to tumor-associated integrins (<i>K</i>_I = 1.8 nM/peptide). Fluorescence and electron microscopy showed that selective integrin-mediated internalization was observed only in cancer cells treated with the peptide-labeled QDs, demonstrating that the unlabeled hydrophilic nanoparticles exhibit characteristics of negatively charged fluorescent dye molecules, which typically do not internalize in cells. The biodistribution profiles of intravenously administered QDs in different mouse models of cancer reveal an exceptionally high tumor-to-liver uptake ratio, suggesting that the small sized QDs evaded conventional opsonization and subsequent high uptake in the liver and spleen. The seamless tunability of the QDs over a wide spectral range with only a small increase in size, as well as the ease of labeling the bright and noncytotoxic QDs with biomolecules, provides a platform for multiplexing information, tracking the trafficking of single molecules in cells, and selectively targeting disease biomarkers in living organisms without premature QD opsonization in circulating blood

How Antioxidants, Osmoregulation, Genes and Metabolites Regulate the Late Seeding Tolerance of Rapeseeds (<i>Brassica napus</i> L.) during Wintering

Rapeseed seeding dates are largely delayed under the rice–rape rotation system, but how rapeseeds adapt to the delayed environment remains unclear. Here, five seeding dates (20 October, 30 October, 10 November, 20 November and 30 November, T1 to T5) were set and the dynamic differences between two late-seeding-tolerant (LST) and two late-seeding-sensitive (LSS) rapeseed cultivars were investigated in a field experiment. The growth was significantly repressed and the foldchange (LST/LSS) of yield increased from 1.50-T1 to 2.64-T5 with the delay in seeding. Both LST cultivars showed higher plant coverage than the LSS cultivars according to visible/hyperspectral imaging and the vegetation index acquired from an unmanned aerial vehicle. Fluorescence imaging, DAB and NBT staining showed that the LSS cultivars suffered more stress damage than the LST cultivars. Antioxidant enzymes (SOD, POD, CAT, APX) and osmoregulation substances (proline, soluble sugar, soluble protein) were decreased with the delay in seeding, while the LST cultivar levels were higher than those of the LSS cultivars. A comparative analysis of transcriptomes and metabolomes showed that 55 pathways involving 123 differentially expressed genes (DEGs) and 107 differentially accumulated metabolites (DAMs) participated in late seeding tolerance regulation, while 39 pathways involving 60 DEGs and 68 DAMs were related to sensitivity. Levanbiose, α-isopropylmalate, s-ribosyl-L-homocysteine, lauroyl-CoA and argino-succinate were differentially accumulated in both cultivars, while genes including isocitrate dehydrogenase, pyruvate kinase, phosphoenolpyruvate carboxykinase and newgene_7532 were also largely regulated. This study revealed the dynamic regulation mechanisms of rapeseeds on late seeding conditions, which showed considerable potential for the genetic improvement of rapeseed

Table_1_CRISPR/Cas9-mediated editing of double loci of BnFAD2 increased the seed oleic acid content of rapeseed (Brassica napus L.).xlsx

Seed oleic acid is an important quality trait sought in rapeseed breeding programs. Many methods exist to increase seed oleic acid content, such as the CRISPR/Cas9-mediated genome editing system, yet there is no report on seed oleic acid content improvement via this system’s precise editing of the double loci of BnFAD2. Here, a precise CRISPR/Cas9-mediated genome editing of the encoded double loci (A5 and C5) of BnFAD2 was established. The results demonstrated high efficiency of regeneration and transformation, with the rapeseed genotype screened in ratios of 20.18% and 85.46%, respectively. The total editing efficiency was 64.35%, whereas the single locus- and double locus-edited ratios were 21.58% and 78.42%, respectively. The relative proportion of oleic acid with other fatty acids in seed oil of mutants was significantly higher for those that underwent the editing on A5 copy than that on C5 copy, but it was still less than 80%. For double locus-edited mutants, their relative proportion of oleic acid was more than 85% in the T1 and T4 generations. A comparison of the sequences between the double locus-edited mutants and reference showed that no transgenic border sequences were detected from the transformed vector. Analysis of the BnFAD2 sequence on A5 and C5 at the mutated locus of double loci mutants uncovered evidence for base deletion and insertion, and combination. Further, no editing issue of FAD2 on the copy of A1 was detected on the three targeted editing regions. Seed yield, yield component, oil content, and relative proportion of oleic acid between one selected double loci-edited mutant and wild type were also compared. These results showed that although the number of siliques per plant of the wild type was significantly higher than those of the mutant, the differences in seed yield and oil content were not significant between them, albeit with the mutant having a markedly higher relative proportion of oleic acid. Altogether, our results confirmed that the established CRISPR/Cas9-mediated genome editing of double loci (A5 and C5) of the BnFAD2 can precisely edit the targeted genes, thereby enhancing the seed oleic acid content to a far greater extent than can a single locus-editing system.</p