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Science, Volume 384, Issue 6691,5 Apr 2024

《明升体育app》第384卷，6691期，2024年4月5日

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明升手机物理Chemical-Physics

Single body-coupled fiber enables chipless textile electronics

单体耦合光纤实现无芯片纺织电子产品

▲作者：WEIFENG YANG, SHAOMEI LIN, WEI GONG, RONGZHOU LIN, CHENGMEI JIANG, XIN YANG, YUNHAO HU, JINGJIE WANG, XIAO XIAO, ,AND HONGZHI

▲链接：

▲ 摘要：

智能纺织品为将科技融入日常生活提供了一个理想的平台。然而，目前的纺织电子系统通常依赖于刚性硅组件，这限制了无缝集成，能源效率和舒适性。由于缺乏动态能量转换载体，无芯片电子系统仍然面临数字逻辑的挑战。

研究者提出了一种无芯片体耦合能量交互机制，用于环境电磁能量收集和单光纤无线信号传输。这种光纤本身可以实现无线视觉数字交互，而不需要在纺织品上安装额外的芯片或电池。

因为所有的电子组件都融合在一个微型纤维中，这有利于可扩展的制造和与现代编织技术的兼容性，从而实现多功能和智能服装。研究者提出了一个可能解决硅基纺织系统问题的策略。

▲ Abstract：

Intelligent textiles provide an ideal platform for merging technology into daily routines. However, current textile electronic systems often rely on rigid silicon components, which limits seamless integration, energy efficiency, and comfort. Chipless electronic systems still face digital logic challenges owing to the lack of dynamic energy-switching carriers. We propose a chipless body-coupled energy interaction mechanism for ambient electromagnetic energy harvesting and wireless signal transmission through a single fiber. The fiber itself enables wireless visual–digital interactions without the need for extra chips or batteries on textiles. Because all of the electronic assemblies are merged in a miniature fiber, this facilitates scalable fabrication and compatibility with modern weaving techniques, thereby enabling versatile and intelligent clothing. We propose a strategy that may address the problems of silicon-based textile systems.

Pseudo-nanostructure and trapped-hole release induce high thermoelectric performance in PbTe

伪纳米结构和困孔释放诱导PbTe具有较高的热电性能

▲作者：BAOHAI JIA, DI WU, LIN XIE, WU WANG, TIAN YU, SHANGYANG LI, YAN WANG, YANJUN XU, BINBIN JIANG, AND JIAQING HE

▲链接：

▲ 摘要：

热电材料可以实现电与热的直接相互转换。然而，由于强纠缠的电和热输运性质，开发提高高热电性能的策略具有挑战性。

研究者展示了在P型碲化铅材料中实现了空位团簇的伪纳米结构和捕获空穴释放的动态载流子调节，从而实现了声子和载流子传输的同时调节。在554开尔文的温差下，研究还在分段模块中实现了~15.5%的能量转换效率。研究展示了中温热电在一系列不同应用中的前景。

▲ Abstract：

Thermoelectric materials can realize direct and mutual conversion between electricity and heat. However, developing a strategy to improve high thermoelectric performance is challenging because of strongly entangled electrical and thermal transport properties. We demonstrate a case in which both pseudo-nanostructures of vacancy clusters and dynamic charge-carrier regulation of trapped-hole release have been achieved in p-type lead telluride–based materials, enabling the simultaneous regulations of phonon and charge carrier transports. We also achieved an energy conversion efficiency of ~15.5% at a temperature difference of 554 kelvin in a segmented module. Our demonstration shows promise for mid-temperature thermoelectrics across a range of different applications.

明升手机Chemistry

Molecularly thin, two-dimensional all-organic perovskites

分子厚度二维全有机钙钛矿

▲作者：HWA SEOB CHOI, JUN LIN, GANG WANG, WALTER P. D. WONG, IN-HYEOK PARK, FANG LIN, JUN YIN, KAI LENG, JUNHAO LIN, AND KIAN PING LOH

▲链接：

▲ 摘要：

近年来，具有三维结构的全有机钙钛矿的出现扩大了钙钛矿材料的潜在应用。然而，二维形式的全有机钙钛矿的合成和利用在很大程度上仍未被探索，因为设计原理尚未开发。

研究者合成了一种无金属的二维层状钙钛矿，表示为CL-v相，明升手机式为A2B2X4，其中A表示比B更大的阳离子，X表示阴离子。CL-v相的介电常数在4.8 ~ 5.5之间，证明了其作为薄膜晶体管栅极介质的潜力。

▲ Abstract：

Recently, the emergence of all-organic perovskites with three-dimensional (3D) structures has expanded the potential applications of perovskite materials. However, the synthesis and utilization of all-organic perovskites in 2D form remain largely unexplored because the design principle has not been developed. We present the successful synthesis of a metal-free 2D layered perovskite, denoted as the Choi-Loh van der Waals phase (CL-v phase), with the chemical formula A2B2X4, where A represents a larger-sized cation compared to B and X denotes an anion. The dielectric constants of the CL-v phase range from 4.8 to 5.5 and we demonstrate their potential as gate dielectrics for thin-film transistors.

Carbon quaternization of redox active esters and olefins by decarboxylative coupling

脱羧偶联氧化还原活性酯和烯烃的碳季铵化反应

▲作者：XU-CHENG GAN, BENXIANG ZHANG, NATHAN DAO, CHENG BI, MAITHILI POKLE, LIYAN KAN, MICHAEL R. COLLINS, CHET C. TYROL, PHILIPPE N. BOLDUC , AND RYAN SHENVI

▲链接：

▲ 摘要：

季碳的合成通常需要许多步骤和复杂的条件或苛刻的试剂，这些试剂作用于高度工程化的底物。研究者手机版了一种简单的催化剂和还原剂组合，将两种类型的原料明升手机品——羧酸和烯烃，通过自由基中间体的季铵化转化为四取代碳。

铁卟啉催化剂通过电子转移或氢原子转移激活每个底物，然后通过双分子均溶取代（SH2）反应将碎片结合。这种交叉偶联减少了从简单的明升手机原料中获得大量含季碳产品的合成负担。

▲ Abstract：

The synthesis of quaternary carbons often requires numerous steps and complex conditions or harsh reagents that act on heavily engineered substrates. This is largely a consequence of conventional polar-bond retrosynthetic disconnections that in turn require multiple functional group interconversions, redox manipulations, and protecting group chemistry. Here, we report a simple catalyst and reductant combination that converts two types of feedstock chemicals, carboxylic acids and olefins, into tetrasubstituted carbons through quaternization of radical intermediates. An iron porphyrin catalyst activates each substrate by electron transfer or hydrogen atom transfer, and then combines the fragments using a bimolecular homolytic substitution （SH2） reaction. This cross-coupling reduces the synthetic burden to procure numerous quaternary carbon– --containing products from simple chemical feedstocks.

农业Agriculture

Joint environmental and social benefits from diversified agriculture

多样化农业带来的环境和社会效益

▲作者：LAURA VANG RASMUSSEN, INGO GRASS, ZIA MEHRABI, OLIVIA M. SMITH, RACHEL BEZNER-KERR, JENNIFER BLESH, LUCAS ALEJANDRO GARIBALDI, MARNEY E. ISAAC, CHRISTINA M. KENNEDY, AND CLAIRE KREMEN

▲链接：

▲ 摘要：

农业单一化的持续扩大是以牺牲农业形式的多样化为代价的。例如这种以集中管理的单一栽培形式进行的简化，对于确保世界处于安全和公正的地球系统边界内构成了风险。

研究者评估了农业多样化如何同时影响社会和环境结果。根据11个国家2655个农场的24项研究，他们展示了专注于牲畜、作物、土壤、非作物种植和水资源保护的五种多样化战略如何有益于社会（如人类福祉、产量和粮食安全）和环境（如生物多样性、生态系统服务和减少环境外部性）的结果。

研究发现，与单一的管理策略相比，应用多种多元化策略能产生更积极的结果。为了实现这些利益，需要设计良好的政策来激励一致采用多种多样化战略。

▲ Abstract：

Agricultural simplification continues to expand at the expense of more diverse forms of agriculture. This simplification, for example, in the form of intensively managed monocultures, poses a risk to keeping the world within safe and just Earth system boundaries. Here, we estimated how agricultural diversification simultaneously affects social and environmental outcomes. Drawing from 24 studies in 11 countries across 2655 farms, we show how five diversification strategies focusing on livestock, crops, soils, noncrop plantings, and water conservation benefit social (e.g., human well-being, yields, and food security) and environmental (e.g., biodiversity, ecosystem services, and reduced environmental externalities) outcomes. We found that applying multiple diversification strategies creates more positive outcomes than individual management strategies alone. To realize these benefits, well-designed policies are needed to incentivize the adoption of multiple diversification strategies in unison.

明升m88明升体育app Life Science

Bronchoconstriction damages airway epithelia by crowding-induced excess cell extrusion

支气管收缩通过拥挤诱导的过度细胞挤压损害气道上皮

▲作者：DUSTIN C. BAGLEY, TOBIAS RUSSELL, ELENA ORTIZ-ZAPATER, SALLY STINSON, KRISTINA FOX, POLLY F. REDD, MERRY JOSEPH, CASSANDRA DEERING-RICE, CHRISTOPHER REILLY , AND JODY ROSENBLATT

▲链接：

▲ 摘要：

哮喘被认为是一种炎症性疾病，其明确的诊断特征是机械性支气管收缩。之前发现了一个保守的过程，称为细胞挤压，当细胞变得过于拥挤时，它会驱动稳态上皮细胞死亡。

新研究表明，支气管收缩发作的病理性拥挤导致大量上皮细胞挤压，从而损害气道，导致小鼠和人类的炎症和黏液分泌。尽管用沙丁胺醇急救治疗放松气道不会影响这些反应，但在支气管收缩过程中抑制活细胞挤压信号会阻止所有这些特征。

研究结果表明，支气管收缩通过过度拥挤诱导的细胞挤压导致上皮损伤和炎症，并表明阻断上皮挤压而不是随后的下游炎症可以阻止前驱哮喘炎症循环。

▲ Abstract：

Asthma is deemed an inflammatory disease, yet the defining diagnostic feature is mechanical bronchoconstriction. We previously discovered a conserved process called cell extrusion that drives homeostatic epithelial cell death when cells become too crowded. In this work, we show that the pathological crowding of a bronchoconstrictive attack causes so much epithelial cell extrusion that it damages the airways, resulting in inflammation and mucus secretion in both mice and humans. Although relaxing the airways with the rescue treatment albuterol did not affect these responses, inhibiting live cell extrusion signaling during bronchoconstriction prevented all these features. Our findings show that bronchoconstriction causes epithelial damage and inflammation by excess crowding-induced cell extrusion and suggest that blocking epithelial extrusion, instead of the ensuing downstream inflammation, could prevent the feed-forward asthma inflammatory cycle.