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71.
Chia-Hwa Lee You-Xiu Zheng Chin-Hsiang Chan Hsin-Mei Ku Chung-Jan Chang Fuh-Jyh Jan 《Molecular Plant Pathology》2020,21(4):571-588
Begomoviruses of the Geminiviridae are usually transmitted by whiteflies and rarely by mechanical inoculation. We used tomato leaf curl New Delhi virus (ToLCNDV), a bipartite begomovirus, to address this issue. Most ToLCNDV isolates are not mechanically transmissible to their natural hosts. The ToLCNDV-OM isolate, originally identified from a diseased oriental melon plant, is mechanically transmissible, while the ToLCNDV-CB isolate, from a diseased cucumber plant, is not. Genetic swapping and pathological tests were performed to identify the molecular determinants involved in mechanical transmission. Various viral infectious clones were constructed and successfully introduced into Nicotiana benthamiana, oriental melon, and cucumber plants by Agrobacterium-mediated inoculation. Mechanical transmissibility was assessed via direct rub inoculation with sap prepared from infected N. benthamiana. The presence or absence of viral DNA in plants was validated by PCR, Southern blotting, and in situ hybridization. The results reveal that mechanical transmissibility is associated with the movement protein (MP) of viral DNA-B in ToLCNDV-OM. However, the nuclear shuttle protein of DNA-B plays no role in mechanical transmission. Analyses of infectious clones carrying a single amino acid substitution reveal that the glutamate at amino acid position 19 of MP in ToLCNDV-OM is critical for mechanical transmissibility. The substitution of glutamate with glycine at this position in the MP of ToLCNDV-OM abolishes mechanical transmissibility. In contrast, the substitution of glycine with glutamate at the 19th amino acid position in the MP of ToLCNDV-CB enables mechanical transmission. This is the first time that a specific geminiviral movement protein has been identified as a determinant of mechanical transmissibility. 相似文献
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Kim Tallaksen Halvorsen Torkel Larsen Howard I. Browman Caroline Durif Nicolai Aasen Leif Asbjørn Vøllestad Alessandro Cresci Tonje Knutsen Sørdalen Reidun M. Bjelland Anne Berit Skiftesvik 《Journal of fish biology》2021,99(4):1513-1518
The movement patterns of three commercially important wrasse (Labridae) species inside a small marine protected area (~ 0.15 km2) on the west coast of Norway were analysed over a period of 21 months. The mean distance between capture and recapture locations varied between 10 and 187 m, and was species and season specific. The extent of movement was not related to body size or sex. These results imply that a network of small strategically located marine protected areas can be used as management tools to protect wrasses from size- and sex-selective fishing mortality. 相似文献
76.
Samuel J. Howarth David C. Kingston Stephen H.M. Brown Ryan B. Graham 《Journal of electromyography and kinesiology》2013,23(4):794-800
Repetitive trunk flexion elicits passive tissue creep, which has been hypothesized to compromise spine stability. The current investigation determined if increased spine flexion angle at the onset of flexion relaxation (FR) in the lumbar extensor musculature was associated with altered dynamic stability of spine kinematics. Twelve male participants performed 125 consecutive cycles of full forward trunk flexion. Spine kinematics and lumbar erector spinae (LES) electromyographic (EMG) activity were obtained throughout the repetitive trunk flexion trial. Dynamic stability was evaluated with maximum finite-time Lyapunov exponents over five sequential blocks of 25 cycles. Spine flexion angle at FR onset, and peak LES EMG activity were determined at baseline and every 25th cycle. Spine flexion angle at FR increased on average by 1.7° after baseline with significant increases of 1.7° and 2.4° at the 50th and 100th cycles. Maximum finite-time Lyapunov exponents demonstrated a transient, non-statistically significant, increase between cycles 26 and 50 followed by a recovery to baseline over the remainder of the repetitive trunk flexion cycles. Recovery of dynamic stability may be the consequence of increased active spine stiffness demonstrated by the non-significant increase in peak LES EMG that occurred as the repetitive trunk flexion progressed. 相似文献
77.
Chang Man Ha Eun Mi Hwang Eunju Kim Da Yong Lee Sunghoe Chang Byung Ju Lee Seong-Geun Hong Jae-Yong Park 《Molecules and cells》2013,36(6):527-533
Neural epidermal growth factor-like protein-like 2 (NELL2) is a secreted glycoprotein that is predominantly expressed in the nervous system, but little is known about the intracellular movement and secretion mechanism of this protein. By monitoring the localization and movements of enhanced green fluorescent protein (EGFP)-labeled NELL2 in living cultured hippocampal neuroprogenitor HiB5 cells, we determined the subcellular localization of NELL2 and its intracellular movement and secretion mechanism. Cterminal EGFP-fused NELL2 showed a typical expression pattern of secreted proteins, especially with respect to its localization in the endoplasmic reticulum, Golgi apparatus, and punctate structures. Vesicles containing NELL2 exhibited bidirectional movement in HiB5 cells. The majority of the vesicles (70.1%) moved in an anterograde direction with an average velocity of 0.454 μm/s, whereas some vesicles (28.7%) showed retrograde movement with an average velocity of 0.302 μm/s. The movement patterns of NELL2 vesicles were dependent upon the presence of microtubules in HiB5 cells. Anterograde movement of NELL2 did not lead to a detectable accumulation of NELL2 in the peripheral region of the cell, indicating that it was secreted into the culture medium. We also showed that the N-terminal 29 amino acids of NELL2 were important for secretion of this protein. Taken together, these results strongly suggest that the N-terminal region of NELL2 determines both the pattern of its intracellular expression and transport of NELL2 vesicles by high-velocity movement. Therefore, NELL2 may affect the cellular activity of cells in a paracrine or autocrine manner. 相似文献
78.
Fabio Martínez Francisco Gómez 《Computer methods in biomechanics and biomedical engineering》2013,16(6):561-572
The gait pattern of a particular patient can be altered in a large set of pathologies. Tracking the body centre-of-mass (CoM) during the gait allows a quantitative evaluation of these diseases at comparing the gait with normal patterns. A correct estimation of this variable is still an open question because of its non-linearity and inaccurate location. This paper presents a novel strategy for tracking the CoM, using a biomechanical gait model whose parameters are determined by a Bayesian strategy. A particle filter is herein implemented for predicting the model parameters from a set of markers located at the sacral zone. The present approach is compared with other conventional tracking methods and decreases the calculated root mean squared error in about a 56% in the x-axis and 59% in the y-axis. 相似文献
79.
Amy L. Fletcher 《New genetics and society》2013,32(1):3-14
This case study of the Estonian Genome Project (EGP) analyses the Estonian policy decision to construct a national human gene bank. Drawing upon qualitative data from newspaper articles and public policy documents, it focuses on how proponents use discourse to link the EGP to the broader political goal of securing Estonia's position within the Western/European scientific and cultural space. This dominant narrative is then situated within the analytical notion of the “brand state”, which raises potentially negative political consequences for this type of market‐driven genomic research. Considered against the increasing number of countries engaging in gene bank and/or gene database projects, this analysis of Estonia elucidates issues that cross national boundaries, while also illuminating factors specific to this small, post‐Soviet state as it enters the global biocybernetic economy. 相似文献
80.
Su-30飞行员在模拟飞行任务中的眼动指标分析 总被引:1,自引:0,他引:1
目的:获取战斗机飞行员在模拟飞行任务中的注意力分配情况和工作负荷的变化,为以后的飞行训练提供技术指导。方法:让十八名SU-30飞行员在模拟飞行器上完成爬升和翻转任务,同时使用眼动仪记录下飞行员的眼动数据,将数据源划分为外景、地平仪、高度表、速度表和综合电子屏显五个区域,并对这五个区域的眼动的数据进行分析对比。结果:在两种任务下,飞行员均在在座舱仪表分配更多的注视点和注视时间;在翻转任务中,飞行员在各个兴趣区的瞳孔直径都小于爬升任务中的直径;扫视幅度随着任务难度的加大而减小。结论:眼动技术可以作为测量飞行员注意力分配的有效方法;不同的任务下飞行员有不同的注意力分配模式,飞行员注意力主要集中在座舱仪表内;翻转任务比爬升任务在仪表上分配了更多的注意力,获取飞行员的注意力分配模式可以为飞行学员训练提供参考。 相似文献