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71.
“Discharge of treated wastewater and sewage sludge landfilling” are the most common practice, which poses threats to the local environment. In this work we first constructed a general sewage treatment ecosystem (STE) which integrated the three systems. Emergy synthesis, with several improved emergy-based indicators which considered the waste input contribution and impacts of emissions, was applied to evaluate two alternative scenarios (scenario 1: sewage treatment system + treated water discharge + sludge landfilling; scenario 2: sewage treatment subsystem + reclaimed water reuse subsystem + aerobic compost production subsystem) for Mingjingtan sewage treatment plant in Wanzhou City of Chongqing in China. Results point out the environmental pressure of scenario 2 is much smaller than scenario 1 although its economic performance is somewhat poorer than scenario 1, and finally the sustainability of scenario 2 is still much better than scenario 1. Therefore, the treated water and sewage sludge reuse can further improve the environmental benefit of the sewage treatment process; however, the STE should be optimized in order to enhance its economic benefit. The proposed methods can help policy-makers make decisions and guide designers and operators to improve the comprehensive performance of sewage treatment processes. In addition, this paper also briefly discusses wastewater integrated management strategy.  相似文献   
72.
Plant resistance (R) proteins provide a robust surveillance system to defend against potential pathogens. Despite their importance in plant innate immunity, relatively few of the ∼170 R proteins in Arabidopsis have well-characterized resistance specificity. In order to identify the R protein responsible for recognition of the Pseudomonas syringae type III secreted effector (T3SE) HopZ1a, we assembled an Arabidopsis R gene T–DNA Insertion Collection (ARTIC) from publicly available Arabidopsis thaliana insertion lines and screened it for plants lacking HopZ1a-induced immunity. This reverse genetic screen revealed that the Arabidopsis R protein HOPZ-ACTIVATED RESISTANCE 1 (ZAR1; At3g50950) is required for recognition of HopZ1a in Arabidopsis. ZAR1 belongs to the coiled-coil (CC) class of nucleotide binding site and leucine-rich repeat (NBS–LRR) containing R proteins; however, the ZAR1 CC domain phylogenetically clusters in a clade distinct from other related Arabidopsis R proteins. ZAR1–mediated immunity is independent of several genes required by other R protein signaling pathways, including NDR1 and RAR1, suggesting that ZAR1 possesses distinct signaling requirements. The closely-related T3SE protein, HopZ1b, is still recognized by zar1 Arabidopsis plants indicating that Arabidopsis has evolved at least two independent R proteins to recognize the HopZ T3SE family. Also, in Arabidopsis zar1 plants HopZ1a promotes P. syringae growth indicative of an ancestral virulence function for this T3SE prior to the evolution of recognition by the host resistance protein ZAR1. Our results demonstrate that the Arabidopsis resistance protein ZAR1 confers allele-specific recognition and virulence attenuation of the Pseudomonas syringae T3SE protein HopZ1a.  相似文献   
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Taurine demonstrates multiple cellular functions including a central role as a neurotransmitter, as a trophic factor in CNS development, in maintaining the structural integrity of the membrane, in regulating calcium transport and homeostasis, as an osmolyte, as a neuromodulator and as a neuroprotectant. The neurotransmitter properties of taurine are illustrated by its ability to elicit neuronal hyperpolarization, the presence of specific taurine synthesizing enzyme and receptors in the CNS and the presence of a taurine transporter system. Taurine exerts its neuroprotective functions against the glutamate induced excitotoxicity by reducing the glutamate-induced increase of intracellular calcium level, by shifting the ratio of Bcl-2 and Bad ratio in favor of cell survival and by reducing the ER stress. The presence of metabotropic taurine receptors which are negatively coupled to phospholipase C (PLC) signaling pathway through inhibitory G proteins is proposed, and the evidence supporting this notion is also presented.  相似文献   
76.
Insect ryanodine receptors (RyRs) are the targets of diamide insecticides. Two point mutations G4946E and I4790M (numbering according to Plutella xylostella, PxRyR) in the transmembrane domain of the insect RyRs associated with diamide resistance have so far been identified in three lepidopteran pests, P. xylostella, Tuta absoluta and Chilo suppressalis. In this study, we identified one of the known RyR target site resistance mutations (I4790M) in a field‐collected population of Spodoptera exigua. The field‐collected WF population of S. exigua exhibited 154 fold resistance to chlorantraniliprole when compared with the susceptible WH‐S strain. Sequencing the transmembrane domains of S. exigua RyR (SeRyR) revealed that the resistant WF strain was homozygous for the I4743M mutation (corresponding to I4790M in PxRyR), whereas the G4900E allele (corresponding to G4946E of PxRyR) was not detected. The 4743M allele was introgressed into the susceptible WH‐S strain by crossing WF with WH‐S, followed by three rounds of backcrossing with WH‐S. The introgressed strain 4743M was homozygous for the mutant 4743M allele and shared about 94% of its genetic background with that of the recipient WH‐S strain. Compared with WH‐S, the near‐isogenic 4743M strain showed moderate levels of resistance to chlorantraniliprole (21 fold), cyantraniliprole (25 fold) and flubendiamide (22 fold), suggesting that the I4743M mutation confers medium levels of resistance to all three diamides. Genetic analysis showed diamide resistance in the 4743M strain was inherited as an autosomal and recessive trait. Results from this study have direct implications for the design of appropriate resistance monitoring and management practices to sustainably control S. exigua.  相似文献   
77.
Western flower thrip, Frankliniella occidentalis (Pergande), is among the most economically important agricultural pests globally, attacking a wide range of vegetable and horticultural crops. In addition to causing extensive crop damage, the species is notorious for vectoring destructive plant viruses, mainly belonging to the genera Orthotospovirus, Ilarvirus, Alphacarmovirus and Machlomovirus. Once infected by orthotospoviruses, thrips can remain virulent throughout their lifespan and continue transmitting viruses to host plants when and wherever they feed. These irruptive viral outbreaks in crops will permanently disrupt functional integrated pest management systems, and typically require a remedial treatment involving insecticides, contributing to further development of insecticide resistance. To mitigate against this continuing cycle, the most effective management is early and comprehensive surveillance of the pest species and recognition of plant viruses in the field. This review provides information on the pest status of F. occidentalis, discusses the current global status of the viruses vectored by this thrip species, examines the mechanisms involved in transmitting virus‐induced diseases by thrips, and reviews different management strategies, highlighting the potential management tactics developed for various cropping systems. The early surveillance and the utilization of potential methods for control of both F. occidentalis and viruses are proposed.  相似文献   
78.
Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) is a major pathogen of the economic insect silkworm, Bombyx mori. Virus‐encoded microRNAs (miRNAs) have been proven to play important roles in host–pathogen interactions. In this study we identified a BmCPV‐derived miRNA‐like 21 nt small RNA, BmCPV‐miR‐1, from the small RNA deep sequencing of BmCPV‐infected silkworm larvae by stem‐loop quantitative real‐time PCR (qPCR) and investigated its functions with qPCR and lentiviral expression systems. Bombyx mori inhibitor of apoptosis protein (BmIAP) gene was predicted by both target prediction software miRanda and Targetscan to be one of its target genes with a binding site for BmCPV‐miR‐1 at the 5′ untranslated region. It was found that the expression of BmCPV‐miR‐1 and its target gene BmIAP were both up‐regulated in BmCPV‐infected larvae. At the same time, it was confirmed that BmCPV‐miR‐1 could up‐regulate the expression of BmIAP gene in HEK293T cells with lentiviral expression systems and in BmN cells by transfecting mimics. Furthermore, BmCPV‐miR‐1 mimics could up‐regulate the expression level of BmIAP gene in midgut and fat body in the silkworm. In the midgut of BmCPV‐infected larvae, BmCPV‐miR‐1 mimics could be further up‐regulated and inhibitors could lower the virus‐mediated expression of BmIAP gene. With the viral genomic RNA segments S1 and S10 as indicators, BmCPV‐miR‐1 mimics could up‐regulate and inhibitors down‐regulate their replication in the infected silkworm. These results implied that BmCPV‐miR‐1 could inhibit cell apoptosis in the infected silkworm through up‐regulating BmIAP expression, providing the virus with a better cell circumstance for its replication.  相似文献   
79.
Mouse brain tissue extracts at various stages of development show a drastic change in the specific activity of pp(A2′p)2A-[32P]pCp binding protein. Identification of the ppp(A2′p)3A-[32P]pCp binding protein was established by (i) binding to the specific ligand ppp(A2′p)3A-[32P]pCp, (ii) displacement of binding by nanomolar concentration of pppA(pA)3, and (iii) affinity labeling techniques in which periodate oxidized ppp(A2′p)3A-[32P]pC was specifically cross-linked to a protein with a molecular weight of 86 000. These data suggest that the ppp(A2′p)3A-[32P]pCp protein is closely associated with the process of cellular proliferation and differentiation.  相似文献   
80.
The complete nucleotide sequence of mitochondrial genome of the Great bustard (Otis tarda) was determined by using polymerase chain reaction (PCR) method. The genome is 16,849 bp in size, containing 13 protein-coding, 2 ribosomal and 22 transfer RNA genes. Sequences of the tRNA genes can be folded into canonical cloverleaf secondary structure except for tRNA-Cys and tRNA-Ser (AGY), which lose “DHU” arm. Sequence analysis showed that the O. tarda mitochondrial control region (mtCR) contained many elements in common with other avian mtCRs. A microsatellite repeat was found in the 3′-peripheral domain of the O. tarda mtCR. Based on the mitochondrial DNA sequences of 12S rRNA, 16S rRNA and tRNA-Val, a phylogenetic study of Gruiformes was performed. The result showed that Otididae was a sister group to “core Gruiformes” and Charadriiformes with strong support (97% posterior probability values) in Bayesian analysis. The taxonomic status of Rhynochetidae, Mesitornithidae, Pedionomidae and Turnicidae that traditionally belonged to Gruiformes was also discussed in this paper.  相似文献   
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