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61.
The brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae), is an invasive pest that attacks specialty and row crops in North America and Europe. There has been a concerted effort to reduce frequent broad-spectrum insecticide applications made on vulnerable crops. One tool that has emerged recently is the use of long-lasting insecticide-treated nets (LLINs) as a killing agent. Here, we conducted bioassays to evaluate the effect of direct contact on deltamethrin-impregnated LLINs on the behaviour and survivorship of H. halys nymphs and adults in the laboratory. Following exposure at three different durations (1.25, 4.25 or 7.25 min), vertical and horizontal mobility of adults and nymphs and the flight capacity of adults were recorded and compared with individuals that were not exposed (control). Exposure to LLINs reduced the horizontal distance and velocity and increased the angular velocity of adults only but reduced vertical mobility of adults and nymphs. Adult flights were not significantly affected by LLIN exposure. Mortality of adults and nymphs at 7-day post-exposure ranged from 73% to 77% regardless of exposure time. We discuss our findings within the context of the potential for and limitations of deploying LLINs in vulnerable crops to manage H. halys populations.  相似文献   
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63.
Journal of Computational Neuroscience - When two-frame apparent motion stimuli are presented with an appropriate inter-stimulus interval (ISI), motion is perceived in the direction opposite to the...  相似文献   
64.

The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated endonuclease 9 (Cas9) system is being rapidly developed for mutagenesis in higher plants. Ideally, foreign DNA introduced by this system is removed in the breeding of edible crops and vegetables. Here, we report an efficient generation of Cas9-free mutants lacking an allergenic gene, Gly m Bd 30K, using biolistic transformation and the CRISPR/Cas9 system. Five transgenic embryo lines were selected on the basis of hygromycin resistance. Cleaved amplified polymorphic sequence analysis detected only two different mutations in e all of the lines. These results indicate that mutations were induced in the target gene immediately after the delivery of the exogenous gene into the embryo cells. Soybean plantlets (T0 plants) were regenerated from two of the transgenic embryo lines. The segregation pattern of the Cas9 gene in the T1 generation, which included Cas9-free plants, revealed that a single copy number of transgene was integrated in both lines. Immunoblot analysis demonstrated that no Gly m Bd 30K protein accumulated in the Cas9-free plants. Gene expression analysis indicated that nonsense mRNA decay might have occurred in mature mutant seeds. Due to the efficient induction of inheritable mutations and the low integrated transgene copy number in the T0 plants, we could remove foreign DNA easily by genetic segregation in the T1 generation. Our results demonstrate that biolistic transformation of soybean embryos is useful for CRISPR/Cas9-mediated site-directed mutagenesis of soybean for human consumption.

  相似文献   
65.
Landscape and Ecological Engineering - There have been many earlier studies of the biodiversity and ecosystem services of abandoned farmlands, but studies of abandoned villages are limited,...  相似文献   
66.
Landscape and Ecological Engineering - Investigating factors underlying human-wildlife conflicts in agricultural landscapes is important for both preventing crop damage and wildlife conservation....  相似文献   
67.
The reversible phosphorylation of proteins mediates cellular signals in eukaryotic cells. RNA interference inhibits the expression of genes and proteins in a sequence-specific manner and provides a tool to study the functions of target molecules. The effect of RNA interference on protein phosphatase isoforms in HEK-293 cells was examined. Protein phosphatase 1 delta (PP1δ) sequence-specific double-stranded RNA (dsRNA) inhibited mRNA and protein expression of the PP18. This RNA interference did not affect the expression of α and γ1 isoforms of PP1. Transfection of antisense RNA specific for PP1δ also suppressed the expression of PP1δ. It was further demonstrated by an in vitro RNA cleavage assay that extracts of HEK-293 cells catalyzed the processing of dsRNA. This cell line had much stronger mRNA expression of Dicer, an RNase III-like enzyme, than did human osteoblastic MG63 cells. The present results show that RNA interference is a useful tool to distinguish between PP1 isoforms.  相似文献   
68.
Proteomic profiles of the lamina of Ecklonia kurome Okamura, one of the Japanese dominant laminarialean kelps, were investigated by two-dimensional electrophoresis (2-DE) and MALDI-TOF/TOF. Due to the absence of E. kurome DNA or protein databases, homology-based cross-species protein identification was performed using a combination of three database-searching algorithms, Mascot peptide mass fingerprinting, Mascot MS/MS ion search, and mass spectrometry-based BLAST. Proteins were extracted from the lamina by an ethanol/phenol method and subjected to 2-DE (pI 4–7, 10 % polyacrylamide gel). More than 700 spots were detected in the 2-DE gel with CBB, and 93 spots (24 proteins) were successfully identified by MALDI-TOF/TOF and the cross-species database searching. The identified proteins mainly consisted of cytoplasmic carbohydrate metabolic enzymes, chloroplast proteins involved in photosynthesis, and haloperoxidases. Interestingly, vanadium-dependent bromoperoxidases (vBPO), which is thought to be involved in halogen uptake, synthesis of halogenated products, and detoxification of reactive oxygen species, were separated into at least 23 different spots. By comparing mass spectra, amino acid sequences predicted from tandem mass spectra and haloperoxidase activities of the vBPOs, we found that (1) at least two types of vBPOs were expressed in the lamina of E. kurome and (2) two pro-vBPOs might be activated by specific cleavage at N- and C-terminal regions.  相似文献   
69.
Reducing activity of the mTORC1/S6K1 pathway has been shown to extend lifespan in both vertebrate and invertebrate models. For instance, both pharmacological inhibition of mTORC1 with the drug rapamycin or S6K1 knockout extends lifespan in mice. Since studies with invertebrate models suggest that reducing translational activity can increase lifespan, we reasoned that the benefits of decreased mTORC1 or S6K1 activity might be due, at least in part, to a reduction of general translational activity. Here, we report that mice given a single dose of rapamycin have reduced translational activity, while mice receiving multiple injections of rapamycin over 4 weeks show no difference in translational activity compared with vehicle-injected controls. Furthermore, mice lacking S6K1 have no difference in global translational activity compared with wild-type littermates as measured by the percentage of ribosomes that are active in multiple tissues. Translational activity is reduced in S6K1-knockout mice following single injection of rapamycin, demonstrating that rapamycin’s effects on translation can occur independently of S6K1. Taken together, these data suggest that benefits of chronic rapamycin treatment or lack of S6K1 are dissociable from potential benefits of reduced translational activity, instead pointing to a model whereby changes in translation of specific subsets of mRNAs and/or translation-independent effects of reduced mTOR signaling underlie the longevity benefits.  相似文献   
70.
Although iron is reported to be associated with the pathogenesis of chronic kidney disease, it is unknown whether iron participates in the pathophysiology of nephrosclerosis. Here, we investigate whether iron is involved in the development of hypertensive nephropathy and the effects of iron restriction on nephrosclerosis in salt- loaded stroke-prone spontaneously hypertensive rats (SHRSP). SHRSP were given either a normal or high-salt diet for 8 weeks. Another subset of SHRSP were fed a high-salt with iron-restricted diet. SHRSP given a high-salt diet developed severe hypertension and nephrosclerosis. As a result, survival rate was decreased after 8 weeks diet. Importantly, massive iron accumulation and increased iron content were observed in the kidneys of salt-loaded SHRSP, along with increased superoxide production, urinary 8-Hydroxy-2′-deoxyguanosine excretion, and urinary iron excretion; however, these changes were markedly attenuated by iron restriction. Of interest, expression of cellular iron transport proteins, transferrin receptor 1 and divalent metal transporter 1, was increased in the tubules of salt-loaded SHRSP. Notably, iron restriction attenuated the development of severe hypertension and nephrosclerosis, thereby improving survival rate in salt-loaded SHRSP. Taken together, these results suggest a novel mechanism by which iron plays a role in the development of hypertensive nephropathy and establish the effects of iron restriction on salt-induced nephrosclerosis.  相似文献   
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