• 【维多利亚湖丽鱼科鱼快速辐射中不同适应,基因流和杂种形成的种群基因组特征。】 复制标题 收藏 收藏
    DOI:10.1111/mec.12083 复制DOI
    作者列表:Keller I,Wagner CE,Greuter L,Mwaiko S,Selz OM,Sivasundar A,Wittwer S,Seehausen O
    BACKGROUND & AIMS: :Adaptive radiations are an important source of biodiversity and are often characterized by many speciation events in very short succession. It has been proposed that the high speciation rates in these radiations may be fuelled by novel genetic combinations produced in episodes of hybridization among the young species. The role of such hybridization events in the evolutionary history of a group can be investigated by comparing the genealogical relationships inferred from different subsets of loci, but such studies have thus far often been hampered by shallow genetic divergences, especially in young adaptive radiations, and the lack of genome-scale molecular data. Here, we use a genome-wide sampling of SNPs identified within restriction site-associated DNA (RAD) tags to investigate the genomic consistency of patterns of shared ancestry and adaptive divergence among five sympatric cichlid species of two genera, Pundamilia and Mbipia, which form part of the massive adaptive radiation of cichlids in the East African Lake Victoria. Species pairs differ along several axes: male nuptial colouration, feeding ecology, depth distribution, as well as the morphological traits that distinguish the two genera and more subtle morphological differences. Using outlier scan approaches, we identify signals of divergent selection between all species pairs with a number of loci showing parallel patterns in replicated contrasts either between genera or between male colour types. We then create SNP subsets that we expect to be characterized to different extents by selection history and neutral processes and describe phylogenetic and population genetic patterns across these subsets. These analyses reveal very different evolutionary histories for different regions of the genome. To explain these results, we propose at least two intergeneric hybridization events (between Mbipia spp. and Pundamilia spp.) in the evolutionary history of these five species that would have lead to the evolution of novel trait combinations and new species.
    背景与目标: : 适应性辐射是生物多样性的重要来源,通常以非常短的连续发生许多物种形成事件为特征。已经提出,这些辐射中的高物种形成率可能是由年轻物种之间杂交过程中产生的新型遗传组合推动的。可以通过比较从不同基因座子集推断出的系谱关系来研究此类杂交事件在群体进化史中的作用,但是到目前为止,此类研究经常受到浅遗传差异的阻碍,尤其是在年轻的适应性辐射中,以及缺乏基因组规模的分子数据。在这里,我们使用在限制性位点相关DNA (RAD) 标签中鉴定的snp的全基因组采样来研究Pundamilia和Mbipia这两个属的五个同族丽鱼科鱼物种之间共享祖先和适应性差异模式的基因组一致性,构成东非维多利亚湖丽鱼科鱼大规模适应性辐射的一部分。物种对沿几个轴不同: 雄性婚育颜色,摄食生态,深度分布以及区分两个属的形态特征和更细微的形态差异。使用异常值扫描方法,我们可以识别所有物种对之间不同选择的信号,其中许多基因座在属之间或雄性颜色类型之间的复制对比中显示平行模式。然后,我们创建了SNP子集,我们希望通过选择历史和中性过程对其进行不同程度的表征,并描述了这些子集的系统发育和种群遗传模式。这些分析揭示了基因组不同区域的进化历史非常不同。为了解释这些结果,我们在这五个物种的进化史中提出了至少两个属间杂交事件 (在Mbipia spp。和Pundamilia spp。之间),这将导致新的性状组合和新物种的进化。
  • 【真核藻类如何适应西班牙的力拓: 新达尔文主义关于快速适应极端敌对生态系统的提议。】 复制标题 收藏 收藏
    DOI:10.1111/j.1469-8137.2007.02095.x 复制DOI
    作者列表:Costas E,Flores-Moya A,Perdigones N,Maneiro E,Blanco JL,García ME,López-Rodas V
    BACKGROUND & AIMS: :Microalgae contributed 60% of the total biomass in the extremely hostile (pH 2 and metal-rich waters) environment of Rio Tinto (which is used as a model for the astrobiology of Mars). These algae are closely related to nonextreme lineages, suggesting that adaptation to Rio Tinto water (RTW) must occur rapidly. Fitness from both the microalga Dictyosphaerium chlorelloides and the cyanobacterium Microcystis aeruginosa was inhibited when they were cultured in RTW. After further incubation for several weeks, D. chlorelloides survived, as a result of the growth of a variant that was resistant to RTW, but RTW-resistant cells did not appear in M. aeruginosa. A Luria-Delbrück fluctuation test revealed that D. chlorelloides RTW-resistant cells arose randomly by rare spontaneous mutations before the RTW exposure (1.38 x 10(-6) mutants per cell division). The mutants with a diminished fitness are maintained in nonextreme waters as the result of a balance between new RTW-resistant cells arising by mutation and RTW-resistant mutants eliminated by natural selection (equilibrium at c. 15 RTW-resistant per 10(7) wild-type cells). Rapid adaptation of eukaryotic algae to RTW could be the result of selection of RTW-resistant mutants occurring spontaneously in nonextreme populations that arrived fortuitously at the river in the past, or in the present continuously.
    背景与目标: : 在力拓 (用作火星天体生物学模型) 的极端敌对 (pH 2和富含金属的水域) 环境中,微藻贡献了总生物量的60%。这些藻类与非极端谱系密切相关,这表明对力拓水 (RTW) 的适应必须迅速发生。在RTW中培养时,微藻绿藻和蓝藻铜绿微囊藻的适应性均受到抑制。进一步孵育数周后,由于对RTW具有抗性的变体的生长,D. chlorelloides得以存活,但铜绿假单胞菌中未出现RTW抗性细胞。Luria-delbr ü ck波动测试表明,在RTW暴露之前,D. chlorelloides RTW抗性细胞是由罕见的自发突变随机产生的 (每个细胞分裂1.38x10(-6) 个突变体)。由于突变产生的新的RTW抗性细胞与自然选择消除的RTW抗性突变体之间的平衡 (每10(7) 野生型细胞在c. 15 RTW抗性时的平衡),适应性减弱的突变体在非极端水域中得以维持。型细胞)。真核藻类对RTW的快速适应可能是选择在过去或现在连续偶然到达河流的非极端种群中自发发生的RTW抗性突变体的结果。
  • 【全株响应、关键过程和对干旱胁迫的适应: 以水稻为例。】 复制标题 收藏 收藏
    DOI:10.1093/jxb/erl101 复制DOI
    作者列表:Lafitte HR,Yongsheng G,Yan S,Li ZK
    BACKGROUND & AIMS: :Most high-yielding rice cultivars developed for irrigated conditions, including the widely grown lowland variety IR64, are highly susceptible to drought stress. This limits their adoption in rainfed rice environments where there is a risk of water shortage during the growing season. Mapping studies using lowland-by-upland rice populations have provided limited information about the genetic basis of variation in yield under drought. One approach to simultaneously improve and understand rice drought tolerance is to generate backcross populations, select superior lines in managed stress environments, and then evaluate which features of the selected lines differ from the recurrent parent. This approach was been taken with IR64, using a range of tolerant and susceptible cultivars as donor parents. Yields of the selected lines measured across 13 widely contracting water environments were generally greater than IR64, but genotype-by-environment effects were large. Traits expected to vary between IR64 and selected lines are plant height, because many donors were not semi-dwarf types, and maturity, because selection in a terminal stress environment is expected to favour earliness. In these experiments it was found that some lines that performed better under upland drought were indeed taller than IR64, but that shorter lines with good yield under drought could also be identified. In trials where drought stress developed in previously flooded (lowland) fields, height was not associated with performance. There was little change in maturity with selection. Other notable differences between IR64 and the selected backcross lines were in their responses to applied ABA and ethylene in greenhouse experiments at the vegetative stage and in leaf rolling observed under chronic upland stress in the field. These observations are consistent with the hypothesis that adaptive responses to drought can effectively allow for improved performance across a broad range of water environments. The results indicate that the yield of IR64 under drought can be significantly improved by backcrossing with selection under stress. In target environments where drought is infrequent but significant in certain years, improved IR64 with greater drought tolerance would be a valuable option for farmers.
    背景与目标: : 大多数为灌溉条件开发的高产水稻品种,包括广泛种植的低地品种IR64,都极易受到干旱胁迫的影响。这限制了它们在生长季节有缺水风险的雨养水稻环境中的采用。使用低地旱稻种群进行的作图研究提供了有关干旱条件下产量变化的遗传基础的有限信息。同时改善和了解水稻耐旱性的一种方法是生成回交种群,在受管理的胁迫环境中选择优良的品系,然后评估所选品系的哪些特征与轮回亲本不同。IR64采用了这种方法,使用了一系列耐性和易感品种作为供体亲本。在13个广泛收缩的水环境中测得的选定品系的产量通常大于IR64,但基因型对环境的影响很大。预计在IR64和选定品系之间变化的性状是植物高度,因为许多供体不是半矮化类型,而成熟度则是,因为在末端胁迫环境中进行选择有望有利于早熟。在这些实验中,发现某些在高地干旱下表现更好的品系确实比IR64高,但是在干旱下也可以确定产量较高的短品系。在先前被洪水淹没的 (低地) 田地中出现干旱胁迫的试验中,高度与性能无关。选择的成熟度几乎没有变化。IR64与选定的回交系之间的其他显着差异在于它们在营养阶段的温室实验中对ABA和乙烯的响应以及在田间长期高地胁迫下观察到的叶片滚动。这些观察结果与以下假设一致: 对干旱的适应性反应可以有效地改善各种水环境的性能。结果表明,在干旱条件下,通过选择回交可以显着提高IR64的产量。在干旱很少发生但在某些年份很严重的目标环境中,对农民来说,提高IR64的耐旱性将是一个有价值的选择。
  • 【m170响应的快速适应: 面部零件的重要性。】 复制标题 收藏 收藏
    DOI:10.1093/cercor/bhm078 复制DOI
    作者列表:Harris A,Nakayama K
    BACKGROUND & AIMS: :Face perception is often characterized as depending on configural, rather than part-based, processing. Here we examined the relative contributions of configuration and parts to early "face-selective" processing at the M170, a magnetoencephalographic response approximately 170 ms after stimulus onset, using adaptation. Previously (Harris and Nakayama 2007), we showed that rapid successive presentation of 2 stimuli (stimulus-onset asynchrony < 800 ms) attenuates the M170 response. Such adaptation is face-selective, with greater attenuation when faces are preceded by other faces than by houses. This technique therefore provides an independent method to assess the nature of this early neurophysiological marker. In these experiments, we measured the adapting power of face configurations versus parts using upright and inverted faces (Experiment 1), face-like configurations of black ovals versus scrambled nonface configurations of face parts (Experiment 2), and isolated face parts (Experiment 3). Although face configurations alone do not produce face-selective adaptation, scrambled and even isolated face parts adapt the M170 response to a similar extent as full faces. Thus, at least for the relatively early face-selective M170 response, face parts produce face-selective adaptation but face configurations do not. These results suggest that face parts are important at relatively early stages of face perception.
    背景与目标: : 面部感知通常被描述为依赖于配置,而不是基于部分的处理。在这里,我们使用适应检查了M170的配置和零件对早期 “面部选择性” 处理的相对贡献,M170是刺激开始后约170 ms的脑磁图响应。以前 (Harris和Nakayama 2007),我们显示了2个刺激的快速连续呈现 (刺激开始异步 <800 ms) 减弱了M170反应。这种适应是面部选择性的,当面部前面有其他面部而不是房屋时,衰减更大。因此,该技术提供了一种独立的方法来评估这种早期神经生理学标记物的性质。在这些实验中,我们测量了面部配置与使用直立和倒置面部的零件的适应性 (实验1),黑色椭圆形的面部配置与面部部分的加扰的非面部配置 (实验2) 以及孤立的面部部分 (实验3)。尽管单独的面部配置不会产生面部选择性适应,但加扰甚至孤立的面部部件使M170响应适应的程度与全面部相似。因此,至少对于相对早期的面部选择性M170响应,面部部分产生面部选择性适应,但面部配置不会。这些结果表明,面部部分在面部感知的相对早期阶段很重要。
  • 【进化救援和适应突然的环境变化取决于压力的历史。】 复制标题 收藏 收藏
    DOI:10.1098/rstb.2012.0079 复制DOI
    作者列表:Gonzalez A,Bell G
    BACKGROUND & AIMS: :Whether evolution will be rapid enough to rescue declining populations will depend upon population size, the supply of genetic variation, the degree of maladaptation and the historical direction of selection. We examined whether the level of environmental stress experienced by a population prior to abrupt environmental change affects the probability of evolutionary rescue (ER). Hundreds of populations of two species of yeast, Saccharomyces cerevisiae and Saccharomyces paradoxus were exposed to a range of sublethal concentrations of salt for approximately a hundred generations before transfer to a concentration of salt lethal to the ancestor (150 g l(-1) NaCl). The fitness of surviving populations of both species was a quadratic function of yield: fitness was greatest for large populations that had been selected on low salt concentrations (less than 20 g l(-1) NaCl) and small populations that had adapted to high salt (more than 80 g l(-1) NaCl). However, differences occurred between species in the probability of ER. The frequency of ER was positively correlated with salt concentration for S. cerevisiae, but negatively correlated with salt concentration in S. paradoxus. These results not only demonstrate that past environmental conditions can determine the probability of ER after abrupt environmental change, but also suggest that there may even be differences between closely related species that are worth further exploration.
    背景与目标: : 进化是否足够快以挽救不断下降的种群,将取决于种群规模,遗传变异的供应,适应不良的程度和选择的历史方向。我们检查了在突然的环境变化之前人口经历的环境压力水平是否会影响进化救援 (ER) 的可能性。在转移到对祖先致命的盐浓度 (150g l(-1) NaCl) 之前,将两种酵母,酿酒酵母和悖论酵母的数百个种群暴露于一定范围的亚致死浓度的盐,持续约一百代。两种物种的存活种群的适应性是产量的二次函数: 对于以低盐浓度 (小于20g l(-1) NaCl) 选择的大种群和适应高盐 (大于80g l(-1) NaCl) 的小种群,适应性最高。然而,物种之间的ER概率存在差异。ER的频率与酿酒酵母的盐浓度呈正相关,而与食盐浓度呈负相关。这些结果不仅表明过去的环境条件可以确定环境突然变化后ER的可能性,而且还表明密切相关的物种之间甚至可能存在差异,值得进一步探索。
  • 【90 kDa热休克蛋白在巴西副球菌适应不同环境条件期间的参与。】 复制标题 收藏 收藏
    DOI:10.1016/j.fgb.2012.11.005 复制DOI
    作者列表:Tamayo D,Muñoz JF,Torres I,Almeida AJ,Restrepo A,McEwen JG,Hernández O
    BACKGROUND & AIMS: :HSP90 is a molecular chaperone that participates in folding, stabilization, activation, and assembly of several proteins, all of which are key regulators in cell signaling. In dimorphic pathogenic fungi such as Paracoccidioides brasiliensis, the adaptation to a higher temperature, acid pH and oxidative stress, is an essential event for fungal survival and also for the establishing of the infectious process. To further understand the role of this protein, we used antisense RNA technology to generate a P. brasiliensis isolate with reduced PbHSP90 gene expression (PbHSP90-aRNA). Reduced expression of HSP90 decreased yeast cell viability during batch culture growth and increased susceptibility to acid pH environments and imposed oxidative stress. Also, PbHSP90-aRNA yeast cells presented reduced viability upon interaction with macrophages. The findings presented here suggest a protective role for HSP90 during adaptation to hostile environments, one that promotes survival of the fungus during host-pathogen interactions.
    背景与目标: : HSP90是一种分子伴侣,参与多种蛋白质的折叠,稳定,激活和组装,所有这些蛋白质都是细胞信号传导的关键调节剂。在双态致病性真菌 (例如巴西Paracoccidioides brasiliensis) 中,适应较高的温度,酸性pH和氧化应激是真菌存活以及建立感染过程的重要事件。为了进一步了解该蛋白的作用,我们使用反义RNA技术生成了具有降低PbHSP90基因表达 (PbHSP90-aRNA) 的巴西假单胞菌分离株。HSP90的表达降低了分批培养过程中酵母细胞的活力,并增加了对酸性pH环境的敏感性并施加了氧化应激。此外,PbHSP90-aRNA酵母细胞在与巨噬细胞相互作用时表现出降低的活力。此处提出的发现表明,HSP90在适应敌对环境期间具有保护作用,在宿主-病原体相互作用期间可促进真菌的存活。
  • 【帕金森病视觉运动适应的学习和巩固。】 复制标题 收藏 收藏
    DOI:10.1016/j.parkreldis.2008.02.012 复制DOI
    作者列表:Marinelli L,Crupi D,Di Rocco A,Bove M,Eidelberg D,Abbruzzese G,Ghilardi MF
    BACKGROUND & AIMS: :We have previously shown in normal subjects that motor adaptation to imposed visual rotation is significantly enhanced when tested few days later. This occurs through a process of sleep-dependent memory consolidation. Here we ascertained whether patients with Parkinson's disease (PD) learn, improve, and retain new motor skills in the same way as normal subjects. We tested 16 patients in early stages of PD and 21 control subjects over two days. All subjects performed reaching movements on a digitizing tablet. Vision of the limb was precluded with an opaque screen; hand paths were shown on the screen with the targets' position. Unbeknownst to the subjects, the hand path on the screen was rotated by 30 degrees . In experiment 1, patients taking dopaminergic treatment and controls adapted to rotation with targets appearing in an unpredictable order. In experiment 2, drug-naïve patients and controls adapted to rotation in a less challenging task where target's appearance was predictable. Patients and controls made similar movements and adapted to rotation in the same way. However, when tested again over the following days, controls' performance significantly improved compared to training, while patients' performance did not. This lack of consolidation, which is present in the early stages of the disease and is independent from therapy, may be due to abnormal homeostatic processes that occur during sleep.
    背景与目标: : 我们先前已经在正常受试者中表明,几天后进行测试时,对施加的视觉旋转的运动适应性显着增强。这是通过依赖睡眠的记忆巩固过程发生的。在这里,我们确定帕金森氏病 (PD) 患者是否以与正常人相同的方式学习,改善和保留新的运动技能。我们在两天内测试了16名PD早期患者和21名对照受试者。所有受试者都在数字化平板电脑上进行了伸手动作。不透明的屏幕阻止了肢体的视力; 屏幕上显示了目标位置的手路径。受试者不知道,屏幕上的手路径旋转了30度。在实验1中,接受多巴胺能治疗的患者和对照适应旋转,目标以不可预测的顺序出现。在实验2中,未接受药物治疗的患者和对照组适应了一项挑战性较小的任务,而目标的外观是可预测的。患者和对照组进行了类似的运动,并以相同的方式适应了旋转。但是,在接下来的几天中再次进行测试时,与训练相比,对照组的表现显着改善,而患者的表现却没有。这种缺乏巩固,存在于疾病的早期阶段,独立于治疗,可能是由于睡眠期间发生的异常稳态过程。
  • 【果蝇中微生物群的饮食适应需要对翻译调节剂4E-BP的NF-κ b依赖性控制。】 复制标题 收藏 收藏
    DOI:10.1016/j.celrep.2020.107736 复制DOI
    作者列表:Vandehoef C,Molaei M,Karpac J
    BACKGROUND & AIMS: :Dietary nutrients shape complex interactions between hosts and their commensal gut bacteria, further promoting flexibility in host-microbiota associations that can drive nutritional symbiosis. However, it remains less clear if diet-dependent host signaling mechanisms also influence these associations. Using Drosophila, we show here that nuclear factor κB (NF-κB)/Relish, an innate immune transcription factor emerging as a signaling node linking nutrient-immune-metabolic interactions, is vital to adapt gut microbiota species composition to host diet macronutrient composition. We find that Relish is required within midgut enterocytes to amplify host-Lactobacillus associations, an important bacterial mediator of nutritional symbiosis, and thus modulate microbiota composition in response to dietary adaptation. Relish limits diet-dependent transcriptional inducibility of the cap-dependent translation inhibitor 4E-BP/Thor to control microbiota composition. Furthermore, maintaining cap-dependent translation in response to dietary adaptation is critical to amplify host-Lactobacillus associations. These results highlight that NF-κB-dependent host signaling mechanisms, in coordination with host translation control, shape diet-microbiota interactions.
    背景与目标: : 膳食营养素形成宿主与其共生肠道细菌之间复杂的相互作用,进一步促进宿主-微生物群关联的灵活性,从而推动营养共生。然而,尚不清楚依赖饮食的宿主信号传导机制是否也会影响这些关联。使用果蝇,我们在这里显示核因子 κ b (NF-κ b)/Relish,一种先天免疫转录因子,作为连接营养-免疫-代谢相互作用的信号节点出现,对于使肠道菌群物种组成适应宿主饮食中的大量营养素组成至关重要。我们发现,在中肠肠细胞中需要津津乐道来扩增宿主-乳酸菌的关联,这是营养共生的重要细菌介质,从而响应饮食适应来调节微生物群的组成。Relish限制了cap依赖性翻译抑制剂4E-BP/Thor的饮食依赖性转录诱导性,以控制微生物群组成。此外,保持对饮食适应的cap依赖性翻译对于扩增宿主-乳杆菌的关联至关重要。这些结果突出表明,NF-κ b依赖性宿主信号传导机制与宿主翻译控制相协调,塑造了饮食与微生物群的相互作用。
  • 【Euryhaline Javafish Medaka,Oryzias javanicus的基因组序列: 用于研究盐度适应的小型水族馆鱼类模型。】 复制标题 收藏 收藏
    DOI:10.1534/g3.119.400725 复制DOI
    作者列表:Takehana Y,Zahm M,Cabau C,Klopp C,Roques C,Bouchez O,Donnadieu C,Barrachina C,Journot L,Kawaguchi M,Yasumasu S,Ansai S,Naruse K,Inoue K,Shinzato C,Schartl M,Guiguen Y,Herpin A
    BACKGROUND & AIMS: :The genus Oryzias consists of 35 medaka-fish species each exhibiting various ecological, morphological and physiological peculiarities and adaptations. Beyond of being a comprehensive phylogenetic group for studying intra-genus evolution of several traits like sex determination, behavior, morphology or adaptation through comparative genomic approaches, all medaka species share many advantages of experimental model organisms including small size and short generation time, transparent embryos and genome editing tools for reverse and forward genetic studies. The Java medaka, Oryzias javanicus, is one of the two species of medaka perfectly adapted for living in brackish/sea-waters. Being an important component of the mangrove ecosystem, O. javanicus is also used as a valuable marine test-fish for ecotoxicology studies. Here, we sequenced and assembled the whole genome of O. javanicus, and anticipate this resource will be catalytic for a wide range of comparative genomic, phylogenetic and functional studies. Complementary sequencing approaches including long-read technology and data integration with a genetic map allowed the final assembly of 908 Mbp of the O. javanicus genome. Further analyses estimate that the O. javanicus genome contains 33% of repeat sequences and has a heterozygosity of 0.96%. The achieved draft assembly contains 525 scaffolds with a total length of 809.7 Mbp, a N50 of 6,3 Mbp and a L50 of 37 scaffolds. We identified 21454 predicted transcripts for a total transcriptome size of 57, 146, 583 bps. We provide here a high-quality chromosome scale draft genome assembly of the euryhaline Javafish medaka (321 scaffolds anchored on 24 chromosomes (representing 97.7% of the total bases)), and give emphasis on the evolutionary adaptation to salinity.
    背景与目标: : Oryzias属由35种fish鱼组成,每种鱼都表现出各种生态,形态和生理特性以及适应性。除了通过比较基因组方法研究性别决定,行为,形态或适应性等多种性状的属内进化的综合系统发育组之外,所有的青the物种都具有许多实验模式生物的优势,包括体积小,世代时间短,用于反向和正向遗传研究的透明胚胎和基因组编辑工具。爪哇medaka,Oryzias javanicus,是两个非常适合生活在咸水/海水中的medaka物种之一。O. javanicus是红树林生态系统的重要组成部分,也被用作生态毒理学研究的有价值的海洋试验鱼。在这里,我们对O. javanicus的整个基因组进行了测序和组装,并预计该资源将对广泛的比较基因组,系统发育和功能研究具有催化作用。包括长读技术和与遗传图谱的数据集成在内的互补测序方法允许爪哇爪哇基因组的908 Mbp的最终组装。进一步的分析估计O. javanicus基因组包含重复序列的33% 并且具有0.96% 的杂合性。所实现的草稿组件包含总长度为809.7 Mbp的525支架、6,3 Mbp的N50和37支架的L50。对于57、146、583个bps的总转录组大小,我们确定了21454个预测转录本。我们在这里提供了一个高质量的染色体规模基因组草图组装的euryhaline Javafish medaka (321个支架锚定在24条染色体上 (代表总碱基的97.7%)),并强调了对盐度的进化适应。
  • 【通过生物细胞适应增强上肢的虚拟康复: 虚拟现实对感知的肌肉乏力,游戏性能和用户体验的影响。】 复制标题 收藏 收藏
    DOI:10.1109/TNSRE.2020.2968869 复制DOI
    作者列表:Montoya MF,Munoz JE,Henao OA
    BACKGROUND & AIMS: :Virtual rehabilitation has been used during decades to provide a more personalized, controlled, and enjoyable experience on upper-limb motor rehabilitation. Since novel virtual reality (VR) technologies are now accessible and highly immersive, the challenge for a wide dissemination of virtual rehabilitation in clinical scenarios has shifted from the hardware robustness to the software intelligence. A sophisticated technique that provides physiological intelligence to novel human-computer interaction (HCI) applications is biocybernetic adaptation. The concept emerges from the electrophysiological computing field, and it proposes using body signals to detect human states (e.g. workload or fatigue) and modulate the virtual activity accordingly. This paper evaluates the effects of using biocybernetic adaptation in a virtual rehabilitation game that aims to encourage users to exert at a desirable intensity level while interacting with the virtual environment. The system relies on surface-electromyography (sEMG) signals to detect fatigue levels in real-time and adapt the game challenge dynamically. Perceived fatigue levels, game user experience, and game performance parameters are assessed after playing the game, considering two different visualization modalities: non-immersive (conventional flat screen) and immersive (VR headset). Results revealed how the biocybernetic system in the immersive condition not only produced lower levels of perceived fatigue compared with the non-immersive, but also, created a more enjoyable and positive experience in a controlled experiment with 24 healthy subjects. Moreover, participants in the immersive condition showed a better performance in the virtual game and higher usability levels scored by users compared with the non-immersive condition. To conclude, we highlight the importance of combining novel immersive approaches with physiologically aware systems to enhance the benefits of virtual rehabilitation therapies.
    背景与目标: : 虚拟康复在过去的几十年中一直被用来为上肢运动康复提供更加个性化,可控和愉快的体验。由于新颖的虚拟现实 (VR) 技术现在可以访问并且高度沉浸式,因此在临床场景中广泛传播虚拟康复的挑战已从硬件鲁棒性转向软件智能。生物细胞适应是一种为新型人机交互 (HCI) 应用提供生理智能的复杂技术。该概念来自电生理计算领域,它提出使用身体信号来检测人类状态 (例如工作量或乏力) 并相应地调节虚拟活动。本文评估了在虚拟康复游戏中使用生物细胞适应的效果,该游戏旨在鼓励用户在与虚拟环境交互的同时以理想的强度发挥作用。该系统依靠表面肌电图 (sEMG) 信号来实时检测乏力水平并动态适应游戏挑战。考虑两种不同的可视化方式: 非沉浸式 (常规平板屏幕) 和沉浸式 (VR耳机),在玩游戏后评估感知乏力水平,游戏用户体验和游戏性能参数。结果表明,与非沉浸式相比,沉浸式生物细胞系统不仅产生了较低的感知乏力水平,而且在24位健康受试者的对照实验中创造了更愉快和积极的体验。此外,与非沉浸状态相比,沉浸状态的参与者在虚拟游戏中表现出更好的性能,并且用户获得了更高的可用性水平。最后,我们强调了将新颖的沉浸式方法与生理感知系统相结合以增强虚拟康复疗法的益处的重要性。
  • 【[神经性Orthorexia nervosa和ORTO-11改编成土耳其语]。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Arusoğlu G,Kabakçi E,Köksal G,Merdol TK
    BACKGROUND & AIMS: OBJECTIVE:Orthorexia is a pathological fixation about the consumption of healthy food. The present study aimed to reveal the psychometric properties of the Turkish version of ORTO-15, which was developed to evaluate orthorexia, and to investigate the relationship betweenorthorexia, and eating attitude, obsessive-compulsive symptoms, and some demographic variables. METHOD:The study included 994 participants aged between 19 and 66 years. ORTO-15, the Maudsley Obsessive-Compulsive Inventory, and the Eating Attitude Test-40 were administered to the participants. RESULTS:A 3-factor solution with varimax rotation explained 40.62% of the variance. When 4 items with factor loadings below+/- 0.50 were eliminated from ORTO-15, the Cronbach's alpha coefficient was 0.62. The remaining 11 items were thought to have statistically satisfactory properties for the Turkish version of ORTO and were collectively referred to as ORTO-11. This version was used to investigate the relationship between orthorexia, and eating attitude and obsessive-compulsive symptoms. Pathological eating attitude and obsessive-compulsive symptoms were related to orthorexia. Women exhibited more orthorexic symptoms then men. In the present study high a body mass index was an important variable for orthorexia, but only together with gender (female), pathological eating attitude, and increased obsessive-compulsive symptoms. The results, implications, and limitations of the study are discussed. CONCLUSION:ORTO-11 demonstrated statistically satisfactory properties. Orthorexia was related to pathological eating attitude and obsessive-compulsive symptoms; however, caution should be used when generalizing the reported results.
    背景与目标:
  • 【撤回注意事项: 种子附属物在特定季节中改善物种适应的作用: 以滨藜为例。】 复制标题 收藏 收藏
    DOI:10.1186/s12870-020-02482-5 复制DOI
    作者列表:Wang Z,Zhao Y,Zhang Y,Zhao B,Yang Z,Dong L
    BACKGROUND & AIMS: :An amendment to this paper has been published and can be accessed via the original article.
    背景与目标: : 本文的修正案已经发表,可以通过原始文章访问。
  • 【感觉适应的信息基础: 大鼠桶皮层的熵和单尖峰效率。】 复制标题 收藏 收藏
    DOI:10.1523/JNEUROSCI.1313-13.2013 复制DOI
    作者列表:Adibi M,Clifford CW,Arabzadeh E
    BACKGROUND & AIMS: :We showed recently that exposure to whisker vibrations enhances coding efficiency in rat barrel cortex despite increasing correlations in variability (Adibi et al., 2013). Here, to understand how adaptation achieves this improvement in sensory representation, we decomposed the stimulus information carried in neuronal population activity into its fundamental components in the framework of information theory. In the context of sensory coding, these components are the entropy of the responses across the entire stimulus set (response entropy) and the entropy of the responses conditional on the stimulus (conditional response entropy). We found that adaptation decreased response entropy and conditional response entropy at both the level of single neurons and the pooled activity of neuronal populations. However, the net effect of adaptation was to increase the mutual information because the drop in the conditional entropy outweighed the drop in the response entropy. The information transmitted by a single spike also increased under adaptation. As population size increased, the information content of individual spikes declined but the relative improvement attributable to adaptation was maintained.
    背景与目标: : 我们最近表明,尽管变异性之间的相关性增加,但暴露于晶须振动仍可提高大鼠桶皮层中的编码效率 (Adibi等,2013)。在这里,为了了解适应如何实现感官表现的这种改善,我们在信息论的框架内将神经元群体活动中携带的刺激信息分解为其基本组成部分。在感官编码的上下文中,这些成分是整个刺激集的响应的熵 (响应熵) 和以刺激为条件的响应的熵 (条件响应熵)。我们发现,适应在单个神经元水平和神经元群体的合并活动上都降低了响应熵和条件响应熵。但是,适应的净效果是增加互信息,因为条件熵的下降超过了响应熵的下降。在适应的情况下,单个峰值传输的信息也会增加。随着人口规模的增加,单个峰值的信息含量下降,但归因于适应的相对改善得以保持。
  • 【对环境pH的适应: 整合Rim101和钙调神经磷酸酶信号转导途径。】 复制标题 收藏 收藏
    DOI:10.1111/j.1365-2958.2007.05929.x 复制DOI
    作者列表:Kullas AL,Martin SJ,Davis D
    BACKGROUND & AIMS: :The ability to appropriately respond to environmental conditions is critical for the survival of simple microbes and for development of complex multicellular organisms. Sensing and responding to a given environmental condition requires the integration of numerous signals through one or more signal transduction pathways. This leads to changes in gene expression, and potentially post-translational modifications, that favour growth in the given environment. In the fungus Candida albicans, an important opportunistic pathogen, environmental pH has profound effects on morphology and proper adaptation to extracellular pH is critical for pathogenesis. Here, we demonstrate that the Rim101/PacC pH-sensing pathway acts in parallel to Crz1, via calcineurin, to adapt to alkaline pH. We also show that the Rim101 pathway acts in parallel to Crz2, independent of calcineurin, to adapt to high lithium concentrations and to repress filamentation at acidic pH. Our studies also revealed a novel requirement for Crz1, Crz2 and calcineurin for growth at acidic pH. From these studies, we propose that the Crz1 homologue Crz2 is calcineurin-independent, but like Crz1, acts in parallel to promote specific Rim101-dependent processes. These results establish and begin to dissect the complex interactions between important signal transduction pathways in C. albicans, which are critical for virulence.
    背景与目标: : 对环境条件做出适当反应的能力对于简单微生物的生存和复杂多细胞生物的发育至关重要。感测和响应给定的环境条件需要通过一个或多个信号转导途径整合众多信号。这会导致基因表达的变化,以及潜在的翻译后修饰,从而有利于在给定环境中生长。在重要的机会性病原体白色念珠菌中,环境pH对形态有深远的影响,对细胞外pH的适当适应对发病机理至关重要。在这里,我们证明了Rim101/PacC pH感应途径通过钙调神经磷酸酶与Crz1平行作用,以适应碱性pH。我们还表明,Rim101途径与Crz2平行,独立于钙调神经磷酸酶,以适应高锂浓度并抑制酸性pH下的丝化。我们的研究还揭示了Crz1,Crz2和钙调神经磷酸酶在酸性pH下生长的新需求。从这些研究中,我们建议Crz1同源物Crz2不依赖钙调神经磷酸酶,但与Crz1一样,平行作用以促进特定的Rim101-dependent过程。这些结果建立并开始剖析白色念珠菌重要信号转导途径之间的复杂相互作用,这对毒力至关重要。
  • 【肥胖和II型糖尿病的代谢适应: 肌因子,脂肪因子和肝因子。】 复制标题 收藏 收藏
    DOI:10.3390/ijms18010008 复制DOI
    作者列表:Oh KJ,Lee DS,Kim WK,Han BS,Lee SC,Bae KH
    BACKGROUND & AIMS: :Obesity and type II diabetes are characterized by insulin resistance in peripheral tissues. A high caloric intake combined with a sedentary lifestyle is the leading cause of these conditions. Whole-body insulin resistance and its improvement are the result of the combined actions of each insulin-sensitive organ. Among the fundamental molecular mechanisms by which each organ is able to communicate and engage in cross-talk are cytokines or peptides which stem from secretory organs. Recently, it was reported that several cytokines or peptides are secreted from muscle (myokines), adipose tissue (adipokines) and liver (hepatokines) in response to certain nutrition and/or physical activity conditions. Cytokines exert autocrine, paracrine or endocrine effects for the maintenance of energy homeostasis. The present review is focused on the relationship and cross-talk amongst muscle, adipose tissue and the liver as secretory organs in metabolic diseases.
    背景与目标: : 肥胖和II型糖尿病的特征是外周组织的胰岛素抵抗。高热量摄入加上久坐的生活方式是这些疾病的主要原因。全身胰岛素抵抗及其改善是每个胰岛素敏感器官共同作用的结果。在每个器官能够交流和参与串扰的基本分子机制中,有来自分泌器官的细胞因子或肽。最近,据报道,响应某些营养和/或身体活动条件,从肌肉 (肌动因子),脂肪组织 (脂肪因子) 和肝脏 (肝因子) 分泌了几种细胞因子或肽。细胞因子发挥自分泌,旁分泌或内分泌作用,以维持能量稳态。本综述主要集中在代谢性疾病中肌肉,脂肪组织和肝脏作为分泌器官之间的关系和串扰。

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