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《迷信》论文导读:2019年1月4日

 

 
 
古生物学Paleontology
 
 
 
 
An elephant-sized Late Triassic synapsid with erect limbs
 
体型和大象一样且拥有挺立四肢的晚三叠世单孔亚纲植物
 
▲ 作者:Tomasz Sulej, Grzegorz Nied?wiedzki
 
▲ 链接:
 
http://science.sciencemag.org/content/363/6422/78
 
 
 
▲ 择要:
 
这里,我们形貌了来自波兰晚三叠世的二齿兽Lisowicia bojani。
 
 
 
这是一种巨型单孔亚纲植物,拥有看似挺立的适于行走的四肢。据估测,其四肢长度凌驾4.5米,高度为2.6米,体重达9吨。
 
 
 
Lisowicia是最年老的无可争议的二齿兽,而且是来自三叠世的最大的非恐龙海洋四足植物。制止生长线的缺失和四肢骨头被高度改革的皮质评释了永世的疾速生长,而且让人想到恐龙和哺乳植物。
 
 
 
Lisowicia的发明推翻了三叠世巨型植物群辐射范围于恐龙这一既有画面,而且证明,干群哺乳植物能到达哺乳植物退化史上直到最末期始新世才再次呈现的体型。
 
 
 
▲ Abstract
 
Here, we describe the dicynodont Lisowicia bojani, from the Late Triassic of Poland, a gigantic synapsid with seemingly upright subcursorial limbs that reached an estimated length of more than 4.5 meters, height of 2.6 meters, and body mass of 9 tons. Lisowicia is the youngest undisputed dicynodont and the largest nondinosaurian terrestrial tetrapod from the Triassic. The lack of lines of arrested growth and the highly remodeled cortex of its limb bones suggest permanently rapid growth and recalls that of dinosaurs and mammals. The discovery of Lisowicia overturns the established picture of the Triassic megaherbivore radiation as a phenomenon restricted to dinosaurs and shows that stem-group mammals were capable of reaching body sizes that were not attained again in mammalian evolution untilthe latest Eocene.
 
 
 
 
天气迷信Climate Science
 
 
 
 
The Little Ice Age and 20th-century deep Pacific cooling
 
小冰河期和20世纪平静洋深处变冷
 
▲ 作者:G. Gebbie, P. Huybers
 
▲ 链接:
 
http://science.sciencemag.org/content/363/6422/70
 
 
 
▲ 择要:
 
替换记录表现,在当代人为变暖开端前,环球连续的变冷不停从中世纪暖期延伸到小冰河期。陆地的恒久影象评释,这些历史上的陆地外貌非常同连续举行的深海温度调解存在联系关系。
 
 
 
将陆地模子同当代和古陆地数据联合,孕育发生了如许一种预测,即平静洋深处仍在顺应进入小冰河期的变冷,而外貌陆地和大泰西深处的温度趋向反应了当代变暖。
 
 
 
这一预测被19世纪70年月英国皇家水师“挑衅者”号观察和当代水文学之间得以确认的温度变革证明。
 
 
 
▲ Abstract
 
Proxy records show that before the onset of modern anthropogenic warming, globally coherent cooling occurred from the Medieval Warm Period to the Little Ice Age. The long memory of the ocean suggests that these historical surface anomalies are associated with ongoing deep-ocean temperature adjustments. Combining an ocean model with modern and paleoceanographic data leads to a prediction that the deep Pacific is still adjusting to the cooling going into the Little Ice Age, whereas temperature trends in the surface ocean and deep Atlantic reflect modern warming. This prediction is corroborated by temperature changes identified between the HMS Challenger expedition of the 1870s and modern hydrography.
 
 
 
 
物理学Physics
 
 
 
 
Laser cooling of ions in a neutral plasma
 
中性等离子体中离子的激光冷却
 
▲ 作者:Thomas K. Langin, Grant M. Gorman, Thomas C. Killian
 
▲ 链接:
 
http://science.sciencemag.org/content/363/6422/61
 
 
 
▲ 择要:
 
中性等离子体的激光冷倒是一项挑衅性使命,由于低温通常和等离子体形态相干。
 
 
 
经过使用超冷原子气体光化电离创立的超冷中性等离子体,我们避开了这一停滞而且展现了中性等离子体中离子的激光冷却。在135微秒的冷却后,我们视察到离子温度降落至原来的1/4,最低到达50毫开尔文。
 
 
 
这推进中性等离子体的实行室研讨向强耦合范畴进一步深化,而且逾越盘算输运性子的现有动力论的有用性限定。
 
 
 
▲ Abstract
 
Laser cooling ofa neutral plasma is a challenging task because of the high temperatures typically associated with the plasma state. By using an ultra cold neutral plasma created by photoionization of an ultracold atomic gas, we avoid this obstacle and demonstrate laser cooling of ions in a neutral plasma. After 135 microseconds of cooling, we observed a reduction in ion temperature by up to a factor of four, with the temperature reaching as low as 50 millikelvin. This pushes laboratory studies of neutral plasmas deeper into the strongly coupled regime, beyond the limits of validity of current kinetic theories forcalculating transport properties.
 
 
 
 
动物学Botany
 
 
 
 
Synthetic glycolate metabolism pathwaysstimulate crop growth and productivity in the field
 
分解甘醇酸代谢通路安慰田间作物生长和消费力
 
▲ 作者:Paul F. South, Amanda P. Cavanagh, Helen W. Liu, et al
 
▲ 链接:
 
http://science.sciencemag.org/content/363/6422/eaat9077
 
 
 
▲ 择要:
 
碳三动物必要光呼吸代谢有毒甘醇酸。取决于生长温度,光呼吸可将碳三动物的产量低落20%~50%。
 
 
 
受晚期事情开导,我们将烟草叶绿体安置到分解甘醇酸代谢通路中。这些通路被以为比自然途径越发高效。克制乙醇酸从叶绿体中输入,使颠末分解途径的通量完成了最大化。
 
 
 
担当测试的分解通路使光互助用量子产率进步了20%。在可重现的田间实验中,浩繁纯合系使生物消费力增长了40%多。
 
 
 
这些结果证明,将替换性甘醇酸代谢通路安置到作物叶绿体中同时克制甘醇酸从自然通路的输入,可在农业田间条件下驱动碳三作物产量增长。
 
 
 
▲ Abstract
 
Photorespiration is required in C3 plants to metabolize toxic glycolate. Depending on growing temperatures, photorespiration can reduce yields by 20 to 50% in C3 crops. Inspired by earlier work, we installed into tobacco chloroplasts synthetic glycolate metabolic pathways that are thought to be more efficient than the native pathway. Flux through the synthetic pathways was maximized by inhibiting glycolate export from the chloroplast. The synthetic pathways tested improved photo synthetic quantum yield by 20%. Numerous homozygous transgenic lines increased biomass productivity by >40% in replicated field trials. These results show that engineering alternative glycolate metabolic pathways into crop chloroplasts while inhibiting glycolate export into the native pathway candrive increases in C3 crop yield under agricultural field conditions.
 
 
 
 
生理学Physiology
 
 
 
 
Synaptotagmin-3 drives AMPA receptor endocytosis, depression of synapse strength, and forgetting
 
突触联合卵白3驱动AMPA受体内吞、突触强度克制和遗忘
 
▲ 作者:Ankit Awasthi, Binu Ramachandran, Saheeb Ahmed, et al
 
▲ 链接:
 
http://science.sciencemag.org/content/363/6422/eaav1483
 
 
 
▲ 择要:
 
遗忘很紧张。没有它,在变革情况中所获影象的绝对紧张性便会得到。
 
 
 
我们发明,突触联合卵白3(Syt3)定位于突触后内吞作用地区,而且移除来自突触等离子体膜的AMPA受体,以应对安慰。
 
 
 
AMPA受体内化、永劫程克制(LTD)以及突触强度永劫程加强(LTP)的阑珊必要Syt3的钙敏感,而且经过Syt3敲除而消散。
 
 
 
在空间影象使命中,Syt3被敲除的小鼠可正常学习,但体现出遗忘的缺失。扰乱野生型配景中的Syt3:GluA2联合模仿了LTP阑珊和遗忘的缺失,而这些效应在Syt3敲除配景中被制止。
 
 
 
我们的发明提供了Syt3内化AMPA受体以克制突触强度而且促进遗忘的分子机制。
 
 
 
▲ Abstract
 
Forgetting is important. Without it, the relative importance of acquired memories in a changing environment is lost. We discovered that synaptotagmin-3 (Syt3) localizes to postsynaptic endocytic zones and removes AMPA receptors from synaptic plasma membranes in response to stimulation. AMPA receptor internalization, long-term depression (LTD), and decay of long-termpotentiation (LTP) of synaptic strength required calcium-sensing by Syt3 andwere abolished through Syt3 knockout. In spatial memory tasks, mice in which Syt3 was knocked out learned normally but exhibited a lack of forgetting. Disrupting Syt3:GluA2 binding in a wild-type background mimicked the lack ofLTP decay and lack of forgetting, and these effects were occluded in the Syt3 knockout background. Our findings provide evidence for a molecular mechanism in which Syt3 internalizes AMPA receptors to depress synaptic strength and promote forgetting.
 
 
 
DNA fragility in the parallel evolution of pelvic reduction in stickleback fish
 
棘鱼骨盆丧失平行退化中的DNA软弱性
 
▲ 作者:Kathleen T. Xie, Guliang Wang, Abbey C. Thompson, et al
 
▲ 链接:
 
http://science.sciencemag.org/content/363/6422/81
 
 
 
▲ 择要:
 
退化孕育发生了非常多样的生命情势,但许多特性反复退化,而此中的机制仍未被充实明白。
 
 
 
反复退化的一个经典例子是棘鱼骨盆后鳍的丧失。反复的骨盆丧失映射到Pitx1基因这个骨盆加强子的重复删除。
 
 
 
这里,我们确认了招致这些反复删除的分子特性。Pitx1加强子序列构成体外替换性DNA布局,而且增长了体外的双链断裂和删除。加强子渐变性取决于DNA复制偏向,而且由TG-二核苷酸引发。
 
 
 
模子表现,增长的渐变率能影响同棘鱼和人类相干的生齿统计学条件下的退化。因而,DNA软弱性或有助于表明为何雷同位点通常在平行顺应性退化中被反复使用。
 
 
 
▲ Abstract
 
Evolution generates a remarkable breadth of living forms, but many traits evolve repeatedly, by mechanisms that are still poorly understood. A classic exampleof repeated evolution is the loss of pelvic hindfins in stickleback fish (Gasterosteus aculeatus). Repeated pelvic loss maps to recurrent deletions of apelvic enhancer of the Pitx1 gene. Here, we identify molecular features contributing to these recurrent deletions. Pitx1 enhancer sequences form alternative DNA structures in vitro and increase double-strand breaks anddeletions in vivo. Enhancer mutability depends on DNA replication direction and is caused by TG-dinucleotide repeats. Modeling shows that elevated mutation rates can influence evolution under demographic conditions relevant for sticklebacks and humans. DNA fragility may thus help explain why the same lociare often used repeatedly during parallel adaptive evolution.
 
 
 
A collicular visual cortex: Neocortical space for an ancient midbrain visual structure
 
丘视觉皮层:陈腐中脑视觉布局的新皮层空间
 
▲ 作者:Riccardo Beltramo, Massimo Scanziani
 
▲ 链接:
 
http://science.sciencemag.org/content/363/6422/64
 
 
 
▲ 择要:
 
大脑皮层中的视觉相应被以为依赖于向低级视皮层(V1)的膝状体输出。
 
 
 
简直,V1毁伤本质性地低落了经过皮层的视觉相应。视觉信息还经过上丘(SC)进入皮层,但这一输出对付皮层中视觉相应的功效还不太清晰。
 
 
 
SC毁伤对大脑皮层视觉相应的影响小于V1毁伤,同时好像没有视觉皮质地区完全依赖于SC输出。
 
 
 
我们证明,小鼠大脑侧视觉皮质区的视觉相应不依赖于V1,而且一旦SC静默,便被破除。这一地区在辨认挪动物体方面的体现凌驾V1。
 
 
 
▲ Abstract
 
Visual responses in the cerebral cortex are believed to rely on the geniculate input to the primary visual cortex (V1). Indeed, V1 lesions substantially reduce visual responses through out the cortex. Visual information enters the cortex also through the superior colliculus (SC), but the function of this input on visual responses in the cortex is less clear. SC lesions affect cortical visual responses less than V1 lesions, and no visual cortical area appears to entirely rely on SC inputs. We show that visual responses in a mouse lateral visual cortical area called the postrhinal cortex are independent of V1 and are abolished upon silencing of the SC. This area out performs V1 in discriminating moving objects.
 
 
 
 
康健Health
 
 
 
 
Metagenomic sequencing at the epicenter of the Nigeria 2018 Lassa fever outbreak
 
尼日利亚2018年拉沙热疫情发作中央的宏基因组测序
 
▲ 作者:L. E. Kafetzopoulou, S. T. Pullan, P. Lemey, et al
 
▲ 链接:
 
http://science.sciencemag.org/content/363/6422/74
 
 
 
▲ 择要:
 
2018年尼日利亚拉沙热发病季履历了有史以来最大范围的病例数攀升,从而引发了关于一种感染率降低的病毒株现身的担心。
 
 
 
为相识病例数剧增面前的分子盛行病学,我们初次在疫情发作中央展开了间接来自患者样本的宏基因组纳米孔测序。这种要领遭到目的病原体高度可变的基因组影响。
 
 
 
基因组数据和体系发育重修结果被立刻传送给尼日利亚政府和天下卫生构造,以便为大众卫生应急反响提供信息。
 
 
 
▲ Abstract
 
The 2018 Nigerian Lassa fever season saw the largest ever recorded upsurge of cases, raising concerns over the emergence of a strain with increased transmission rate. To understand the molecular epidemiology of this upsurge, we performed, for the first time at the epicenter of an unfolding outbreak, metagenomic nanopore sequencing directly from patient samples, an approach dictated by the highly variable genome of the target pathogen. Genomic data and phylogenetic reconstructions were communicated immediately to Nigerian authorities and the World Health Organization to inform the public health response.
 
 
 
(宗华)
 
 
 
 
 
 
 
 
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