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材料科学Material Sciences

▲?作者：Jiarui Fu, Takayuki Nakamuro, and Eiichi Nakamura

▲ 链接：

https://www.science.org/doi/10.1126/science.adw2025

▲ 摘要：

金刚石与金刚烷（Ad）虽具有相同的Td对称性碳骨架结构，但将金刚烷转化为金刚石一直面临挑战——该过程需实现碳氢（C–H）键的文导闻科选择性断裂并将单体组装成金刚石晶格。

我们的读新方法不同于传统的高温高压金刚石合成技术。通过在真空环境中以80—200千电子伏特电子束在100—296开尔文温度下辐照金刚烷亚微米晶体数十秒，学网我们成功制备出立方晶结构的科学无缺陷纳米金刚石（NDs），同时伴随氢气逸出。出版

时间分辨透射电子显微镜实时观测到金刚烷寡聚体初步形成并最终转变为球形纳米金刚石的周论WhatsApp%E3%80%90+86%2015855158769%E3%80%91bennetts%20cranes%20ltd过程。显著的文导闻科动力学同位素效应表明C–H键断裂是反应速控步骤，且其他测试碳氢化合物均未能形成纳米金刚石。读新

▲Abstract：

Diamond and 學網adamantane (Ad) share a?Td-symmetric carbon skeleton, but converting Ad to diamond has been challenging because it requires selective carbon-hydrogen (C–H) bond cleavage and monomer assembly into a diamond lattice. Our approach differs from the conventional high-temperature, high-pressure diamond syntheses. We electron-irradiated Ad submicrocrystals at 80 to 200 kilo–electron volts and 100 to 296 kelvin in vacuum for tens of seconds. This process yielded defect-free nanodiamonds (NDs) of cubic crystal structure, accompanied by hydrogen gas evolution. Time-resolved transmission electron microscopy revealed the initial formation of Ad oligomers transforming into spherical NDs. A sizable kinetic isotope effect indicates that C–H cleavage was rate-determining, and other hydrocarbons tested failed to form NDs.

▲?作者：Brian C. Wyatt, Yinan Yang et al.

▲ 链接：

https://www.science.org/doi/10.1126/science.adv4415

▲ 摘要：

在成分复杂的材料中，关于焓与熵对所谓'高熵材料'结构和短程有序化影响的科学问题一直存在争议。为解决这一争议，出版我们合成并研究了40种含2—9种金属的周论M4AlC3层状碳化物相，发现当熵增尚未达到足以实现过渡金属原子面完全无序化之前，焓驱动的短程有序始终存在。

我们将所有这些层状碳化物相转化为二维片层结构，并揭示了有序与无序状态对其表面特性和电子行为的调控作用。本研究证明了焓—熵竞争对多组分材料短程有序的关键影响。

▲ Abstract：

In compositionally complex materials, there is controversy on the effect of enthalpy versus entropy on the structure and short-range ordering in so-called high-entropy materials. To help address this controversy, we synthesized and probed 40 M4AlC3?layered carbide phases containing two to nine metals and found that short-range ordering from enthalpy was present until the entropy increased enough to achieve complete disordering of the transition metals in their atomic planes. We transformed all of these layered carbide phases into two-dimensional (2D) sheets and showed the effects of the order versus disorder on their surface properties and electronic behavior. This study suggests the key effect that the competition between enthalpy and entropy has on short-range order in multicompositional materials.

医学Medicine

▲?作者：Carolina Conte, Maria Lucia Angelotti et al.

▲ 链接：

https://www.science.org/doi/10.1126/science.adp4629

▲ 摘要：

▲ Abstract：

The global burden of kidney disease displays marked sexual dimorphism. Lineage tracing and single-cell RNA-sequencing revealed that starting from puberty, estrogen signaling in female mice supports self-renewal and differentiation of renal progenitors to increase filtration capacity, reducing sensitivity to glomerular injury compared with that of males. This phenomenon accelerated as female kidneys adapted to the workload of pregnancy. Deletion of estrogen receptor α in renal progenitors disrupted this adaptation, leading to preeclampsia, fetal growth restriction, and increased maternal risk of hypertension and chronic kidney disease. Offspring from affected mothers had fewer nephrons, resulting in early-life hypertension and greater susceptibility to kidney disease. These results highlight the fundamental role of kidney fitness and renal progenitors for pregnancy and preeclampsia and as a determinant of sexual dimorphism in kidney disease.

化学Chemsitry

▲?作者：Ping Jin, Pu Guo et al.

▲ 链接：

https://www.science.org/doi/10.1126/science.adq3445

▲ 摘要：

通过二氧化碳加氢制备烯烃是催化领域长期追求的目标。由于高温下异裂氢解离这一关键步骤会导致选择性控制复杂化，常规反应通常生成多碳混合物。在这项研究中，我们报告在365纳米光照下，金—二氧化钛复合材料可在常温条件下诱导氢分子异裂解离。

该过程可能依赖于光生电子与空穴在金属金纳米颗粒和金—氧—钛界面支架上形成的界面电偶极矩。光照诱导的金纳米颗粒表面氧化钛层覆盖进一步促进了氢的异裂解离。在流动反应装置中，光照射下产生的亲核氢物种能以>99%的收率将二氧化碳还原为乙烷。

更重要的是，通过后续光催化乙烷脱氢反应的级联，在超过1500小时的光照过程中实现了>99%收率的乙烯制备。

▲ Abstract：

Producing olefins by carbon dioxide (CO2) hydrogenation is a long-standing goal. The usual products are multicarbon mixtures because the critical step of heterolytic hydrogen (H2) dissociation at high temperatures complicates selectivity control. In this study, we report that irradiating gold–titanium dioxide at 365 nanometers induces heterolytic H2?dissociation at ambient temperature. This process likely relies on interfacial electric dipoles from photogenerated electrons and holes situated on the metallic gold nanoparticles and interfacial gold–oxygen–titanium scaffolds. The heterolytic H2?dissociation is further promoted by light-induced coating of gold nanoparticles with a titanium oxide layer. The resulting nucleophilic hydrogen species reduce CO2?to ethane in >99% yield under light irradiation in a flow apparatus. Furthermore, cascading with a subsequent photocatalytic ethane dehydrogenation generates ethylene in >99% yield over 1500 hours of irradiation.

生物学Biology

▲?作者：Daniel Krueger, Willem Kasper Spoelstra et al.

▲ 链接：

https://www.science.org/doi/10.1126/science.adr8753

▲ 摘要：

细胞挤出对维持肠道上皮稳态自我更新至关重要。肠道绒毛顶端细胞因拥挤导致的压缩，曾被认为是触发挤出的主要因素。在这项研究中，我们发现肠道上皮中收缩细胞间局部的'拔河式'力学竞争才是调控细胞挤出的关键机制。

通过结合定量活体显微技术、光遗传学诱导组织张力、肌球蛋白II活性的遗传干预以及小鼠肠道和肠道类器官中基底皮层局部破坏等技术手段，我们发现动态肌动球蛋白网络在整个肠道绒毛（包括绒毛顶端区域）产生持续性张力。无法维持这种张力的机械弱势细胞最终导致挤出的发生。因此，上皮屏障的完整性取决于细胞间的力学平衡。

▲ Abstract：

Cell extrusion is essential for homeostatic self-renewal of the intestinal epithelium. Extrusion is thought to be triggered by crowding-induced compression of cells at the intestinal villus tip. In this study, we found instead that a local “tug-of-war” competition between contractile cells regulated extrusion in the intestinal epithelium. We combined quantitative live microscopy, optogenetic induction of tissue tension, genetic perturbation of myosin II activity, and local disruption of the basal cortex in mouse intestines and intestinal organoids. These approaches revealed that a dynamic actomyosin network generates tension throughout the intestinal villi, including the villus tip region. Mechanically weak cells unable to maintain this tension underwent extrusion. Thus, epithelial barrier integrity depends on intercellular mechanics.

地球科学Earth Science