天博《自然》（20230921出版）一周论文导读—新闻—科学网
来源：天博企业
发表时间:
2024-07-11
Polarized thermal emission from dust in a galaxy at redshift 2.6
红移2.6处星系中灰尘的偏振热辐射
▲作者：J. E. Geach, E. Lopez-Rodriguez et al.
▲链接：https://www.nature.com/articles/s41586-023-06346-4
▲择要：
于此，咱们陈诉了于一个强透镜、自身发光的星系中，从灰尘颗粒中检测到的线偏振热发射，该星系造成恒星的速率于红移为2.6处是星河系的1000倍以上，于年夜爆炸后的2.5 Gyr内。极化辐射是由灰尘颗粒与局部磁场的对于齐惹起的。
中位极化分数约为1%，与四周的螺旋星系相似。咱们的不雅测成果以为存于一个5千帕秒标准的有序磁场，其强度约为500μG或者更低，标的目的平行在份子气体盘。这一发明证明了如许的布局于宇宙汗青的初期可以于星系中迅速造成。
▲ Abstract：
Here we report the detection of linearly polarized thermal emission from dust grains in a strongly lensed, intrinsically luminous galaxy that is forming stars at a rate more than 1,000 times that of the Milky Way at redshift 2.6, within 2.5 Gyr of the Big Bang. The polarized emission arises from the alignment of dust grains with the local magnetic field. The median polarization fraction is of the order of 1%, similar to nearby spiral galaxies. Our observations support the presence of a 5-kiloparsec-scale ordered magnetic field with a strength of around 500 μG or lower, oriented parallel to the molecular gas disk. This confirms that such structures can be rapidly �첩formed in galaxies, early in cosmic history.
Structure evolution at the gate-tunable suspended graphene–water interface
栅极可调悬浮石墨烯电极—水界面的布局演化
▲作者：Ying Xu, You-Bo Ma, Feng Gu, Shan-Shan Yang Chuan-Shan Tian
▲链接：https://www.nature.com/articles/s41586-023-06374-0
▲择要：
经由过程哄骗以及频光谱，咱们展示了石墨烯—水界面的布局蜕变与栅极电压的瓜葛。Stern层中水的氢键收集于水电解窗口内险些没有变迁，但于电化学反映开启时发生了显著的变迁。
于析氢反映最先时，凸起于石墨烯—水界面的O-H吊挂键就消散了，这注解因为电极四周有过剩的中间物资，石墨烯—水界面的最上层发生了较着的布局变迁。年夜尺寸吊挂的原始石墨烯为展现石墨电极界面的微不雅历程提供了一个新的平台。
▲ Abstract：
Using sum-frequency spectroscopy, here we show the structural evolution versus the gate voltage at the graphene–water interface. The hydrogen-bond network of water in the Stern layer is barely changed within the water-electrolysis window but undergoes notable change when switching on the electrochemical reactions. The dangling O–H bond protruding at the graphene–water interface disappears at the onset of the hydrogen evolution reaction, signifying a marked structural change on the topmost layer owing to excess intermediate species next to the electrode. The large-size suspended pristine graphene offers a new platform to unravel the microscopic processes at the graphitic-electrode interfaces.
Bonding wood with uncondensed lignins as adhesives
用未凝结木质素胶黏剂粘合木料
▲作者：Guangxu Yang, Zhenggang Gong, Xiaolin Luo, Lihui Chen Li Shuai
▲链接：https://www.nature.com/articles/s41586-023-06507-5
▲择要：
于此，咱们陈诉了一种从木质纤维素生物资制备木质素基木料胶黏剂的简朴实用的要领。咱们的要领包孕从生物资中分散未凝结或者略微凝结的木质素，然后间接将木质素悬浮液以及水作为胶粘剂运用在木料贴面上。
这类木质素胶粘剂可以于较宽热压温度规模内制备机能优胜的胶合板产物，使这些胶粘剂于差别的市场范畴成为传统木料胶粘剂的有出路的替换品。机理研究注解，木质素胶粘剂的粘附机制可能包孕木质素被水硬化、木质素硬化后填充导管和胶粘剂中的木质素与细胞壁中的木质素发生交联。
▲ Abstract：
Here we report a simple and practical strategy for preparing lignin-based wood adhesives from lignocellulosic biomass. Our strategy involves separation of uncondensed or slightly condensed lignins from biomass followed by direct application of a suspension of the lignin and water as an adhesive on wood veneers. Plywood products with superior performances could be prepared with such lignin adhesives at a wide range of hot-pressing temperatures, enabling the use of these adhesives as promising alternatives to traditional wood adhesives in different market segments. Mechanistic studies indicate that the adhesion mechanism of such lignin adhesives may involve softening of lignin by water, filling of vessels with softened lignin and crosslinking of lignins in adhesives with those in the cell wall.
Multistable sheets with rewritable patterns for switchable shape-morphing
能用在可切换的外形变形的、具备可重写图案的多不变质料
▲作者：A. S. Meeussen M. van Hecke
▲链接：hhttps://www.nature.com/articles/s41586-023-06353-5
▲择要：
于此，咱们的研究注解基在机械多不变性的外形变形计谋可以降服许多限定。咱们专一在以自不变伤疤模式存储机械刺激影象的颠簸片状质料。于去除了外部刺激后，伤疤会连续存于，并迫使质料切换到特定的弯曲、卷曲或者扭曲外形。
这些不变的外形可以经由过程适量的强迫擦除了，到达答应重写的模式以及强盛驱动的功效。咱们的这一计谋是跨质料的，可扩大到其他颠簸模式以及不不变性，而且对于标准没有限定，可以于从微型到修建尺寸的差别标准上运用。
▲ Abstract：
Here we show that shape-morphing strategies based on mechanical multistability can overcome these limitations. We focus on undulating metasheets that store memories of mechanical stimuli in patterns of self-stabilizing scars. After removing external stimuli, scars persist and force the sheet to switch to sharply selected curved, curled and twisted shapes. These stable shapes can be erased by appropriate forcing, allowing rewritable patterns and repeated and robust actuation. Our strategy is material agnostic, extendable to other undulation patterns and instabilities, and scale-free, allowing applications from miniature to architectural scales.
Coral reefs benefit from reduced land–sea impacts under ocean warming
珊瑚礁于全世界变暖的环境下受益在陆地-海洋影响的削减
▲作者：Jamison M. Gove, Gareth J. Williams et al.
▲链接：https://www.nature.com/articles/s41586-023-06394-w
▲择要：
于此，咱们经由过程联合怪异的20年陆地—海洋人类影响的时间序列去研究珊瑚礁的变迁，此中此中包孕夏威夷史无前例的海洋热浪。遭到草食性鱼类数目增长、陆地要素（如废水污染以及都会径流）削减影响的珊瑚礁，具备正向的珊瑚轨迹滋扰。与鱼类数目削减以及陆地影响加强的珊瑚礁比拟，这些珊瑚礁于严峻热应激后的珊瑚灭亡率也略有降落。
情景模仿注解，与零丁发生任何一种环境比拟，同时削减陆地-海洋人类影响的成果是，于滋扰发生4年后，珊瑚礁具备高造礁笼罩率的可能性要超出跨越3至6倍。咱们的研究成果注解，陆海综合治理可以帮忙实现海洋掩护方针，并为珊瑚礁于不停变迁的天气中保存提供最好时机。
▲ Abstract：
Here we combine surveys of reef change with a unique 20-year time series of land–sea human impacts that encompassed an unprecedented marine heatwave in Hawai‘i. Reefs with increased herbivorous fish populations and reduced land-based impacts, such as wastewater pollution and urban runoff, had positive coral cover trajectories predisturbance. These reefs also experienced a modest reduction in coral mortality following severe heat stress compared to reefs with reduced fish populations and enhanced land-based impacts. Scenario modelling indicated that simultaneously reducing land–sea human impacts results in a three- to sixfold greater probability of a reef having high reef-builder cover four years postdisturbance than if either occurred in isolation. International efforts to protect 30% of Earth’s land and ocean ecosystems by 2030 are underway. Our results reveal that integrated land–sea management could help achieve coastal ocean conservation goals and provide coral reefs with the best opportunity to persist in our changing climate.
Child wasting and concurrent stunting in low- and middle-income countries
低支出以及中等支出国度的儿童瘦削以及并发发育缓慢
▲作者：Andrew Mertens, Jade Benjamin-Chung et al.
▲链接：https://www.nature.com/articles/s41586-023-06480-z#Sec8
▲择要：
于这里，咱们注解瘦削是一个高度动态的病发以及痊愈历程，发生率于出生到3个月之间到达岑岭。于出生头24个月某个时间点呈现瘦削的儿童，比于某个时间点呈现遍及瘦削的儿童要多。
例如，于24个月年夜时，有5.6%的儿童身体瘦削；统一春秋的儿童中，29.2%的儿童至少履历过一次瘦削期间，10.0%履历过两次或者两次以上。于6个月前瘦削的儿童比于较年夜春秋瘦削的儿童恢复患上更快，履历时间更短；然而，初期瘦削增长了后期生长缓慢的危害，包孕同时瘦削以及发育缓慢，从而增长了灭亡危害。
咱们的研究成果注解了经由过程改良产妇养分，成立从出生到6个月年夜婴儿瘦削的干涉干与办法的主要性，这一点可以用在增补今朝着重在6–59个月的儿童的计谋。
▲ Abstract：
Here we analyse 21 longitudinal cohorts and show that wasting is a highly dynamic process of onset and recovery, with incidence peaking between birth and 3 months. Many more children experience an episode of wasting at some point during their first 24 months than prevalent cases at a single point in time suggest. For example, at the age of 24 months, 5.6% of children were wasted, but by the same age (24 months), 29.2% of children had experienced at least one wasting episode and 10.0% had experienced two or more episodes. Children who were wasted before the age of 6 months had a faster recovery and shorter episodes than did children who were wasted at older ages; however, early wasting increased the risk of later growth faltering, including concurrent wasting and stunting (low length-for-age z-score), and thus increased the risk of mortality. Our results show the importance of establishing interventions to prevent wasting from birth to the age of 6 months, probably through improved maternal nutrition, to complement current progra妹妹es that focus on children aged 6–59 months.
/天博
