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Thermostable cross-β structures are characteristic of pathological amyloid fibrils, but these structures cannot explain the reversible nature of fibrils formed by RNA-binding proteins such as fused in sarcoma (FUS), involved in RNA granule assembly. Here, we find that two tandem (S/G)Y(S/G) motifs of the human FUS low-complexity domain (FUS LC) form reversible fibrils in a temperature- and phosphorylation-dependent manner. We named these motifs reversible amyloid cores, or RAC1 and RAC2, and determined their atomic structures in fibrillar forms, using microelectron and X-ray diffraction techniques. The RAC1 structure features an ordered-coil fibril spine rather than the extended β-strand typical of amyloids. Ser42, a phosphorylation site of FUS, is critical in the maintenance of the ordered-coil structure, which explains how phosphorylation controls fibril formation. The RAC2 structure shows a labile fibril spine with a wet interface. These structures illuminate the mechanism of reversible fibril formation and dynamic assembly of RNA granules.

Thermoelectrics have great potential for use in waste heat recovery to improve energy utilization. Moreover, serving as a solid-state heat pump, they have found practical application in cooling electronic products. Nevertheless, the scarcity of commercial Bi 2 Te 3 raw materials has impeded the sustainable and widespread application of thermoelectric technology. In this study, we developed a low-cost and earth-abundant PbS compound with impressive thermoelectric performance. The optimized n-type PbS material achieved a record-high room temperature ZT of 0.64 in this system. Additionally, the first thermoelectric cooling device based on n-type PbS was fabricated, which exhibits a remarkable cooling temperature difference of ~36.9 K at room temperature. Meanwhile, the power generation efficiency of a single-leg device employing our n-type PbS material reaches ~8%, showing significant potential in harvesting waste heat into valuable electrical power. This study demonstrates the feasibility of sustainable n-type PbS as a viable alternative to commercial Bi 2 Te 3 , thereby extending the application of thermoelectrics. The authors fabricate a thermoelectric cooling device based on n-type PbS based material, which exhibits a remarkable cooling temperature difference of 36.9 K at room temperature, and the single-leg power generation efficiency of 8%.

Research on the impacts of climate change on crop yield is crucial for improving agricultural management practices and enhancing climate adaptability. Although previous studies have explored the effects of climate trends and fluctuations on wheat yield, their combined impacts under future climate scenarios in the North China Plain (NCP) remain insufficiently understood. This study employs the DSSAT model to analyze the impacts of future climate trends and fluctuations on winter wheat yield. The results indicate that in the 2030s, the benefits of increased precipitation outweighed the losses from rising temperatures, leading to a 1.5% increase in winter wheat yield in the NCP. However, by the 2080s, continuous temperature rise dominated yield reduction, resulting in a 13.4% decline, which exceeded the compensatory capacity of increased precipitation. Irrigated wheat was primarily influenced by temperature trends, while rainfed systems were more sensitive to precipitation fluctuations. Delaying the planting date and increasing field fertility could mitigate 6–7.5% of the potential losses caused by rising temperatures, whereas increasing irrigation had limited mitigation effects (only improving yield by 3%). This study quantifies the climate impact benefits on winter wheat in the NCP and highlights the need for prioritizing heat-tolerant varieties and optimizing sowing and fertilization practices over water-intensive adaptation strategies. The findings provide decision-making support for ensuring food security under a warming climate.

Associations between gut microbiota and colorectal cancer (CRC) have been widely investigated. However, the replicable markers for early-stage adenoma diagnosis across multiple populations remain elusive. Here, we perform an integrated analysis on 1056 public fecal samples, to identify adenoma-associated microbial markers for early detection of CRC. After adjusting for potential confounders, Random Forest classifiers are constructed with 11 markers to discriminate adenoma from control (area under the ROC curve (AUC) = 0.80), and 26 markers to discriminate adenoma from CRC (AUC = 0.89), respectively. Moreover, we validate the classifiers in two independent cohorts achieving AUCs of 0.78 and 0.84, respectively. Functional analysis reveals that the altered microbiome is characterized with increased ADP- l -glycero-beta- d -manno-heptose biosynthesis in adenoma and elevated menaquinone-10 biosynthesis in CRC. These findings are validated in a newly-collected cohort of 43 samples using quantitative real-time PCR. This work proves the validity of adenoma-specific markers across multi-populations, which would contribute to the early diagnosis and treatment of CRC. The gut microbiome plays an important role in colorectal carcinogenesis and predictive microbiome signatures have been proposed for colorectal cancer (CRC) diagnosis. Here the authors perform a meta-analysis of 16S rRNA-based profiles to identify microbial markers able to discriminate patients with adenoma from control and CRC, building a model that can be applied for the early detection of CRC.

Artificial periodic structures including photonic crystals (PCs) and metamaterials have been widely employed to construct metadevices, whereas their effective refractive indices n e and relative impedances Z r are usually coupled together and hard to design separately. Here, we present a method for flexibly tuning the indices n e and impedances Z r of PCs. The unit cell of PC consists of a dielectric matrix with multiple air holes symmetrically distributed around the center of the unit cell. We find that the index n e of the PC mainly depends on the filling ratio of the dielectric, while its impedance Z r relies on the position of the holes. When the holes have an appropriate distance from the center of the unit cell, matched impedances ( Z r = 1) can be achieved for PCs with different indices n e . As a result, impedance-matched metadevices, such as generalized Mikaelian lenses with high efficiency (> 96%), can be constructed even with high refractive indices in their matrices.

Protein phase separation drives the assembly of membraneless organelles, but little is known about how these membraneless organelles are maintained in a metastable liquid- or gel-like phase rather than proceeding to solid aggregation. Here, we find that human small heat-shock protein 27 (Hsp27), a canonical chaperone that localizes to stress granules (SGs), prevents FUS from undergoing liquid−liquid phase separation (LLPS) via weak interactions with the FUS low complexity (LC) domain. Remarkably, stress-induced phosphorylation of Hsp27 alters its activity, leading Hsp27 to partition with FUS LC to preserve the liquid phase against amyloid fibril formation. NMR spectroscopy demonstrates that Hsp27 uses distinct structural mechanisms for both functions. Our work reveals a fine-tuned regulation of Hsp27 for chaperoning FUS into either a polydispersed state or a LLPS state and suggests an essential role for Hsp27 in stabilizing the dynamic phase of stress granules.The chaperone Hsp27 prevents FUS from undergoing liquid–liquid phase separation until stress-induced phosphorylation causes Hsp27 to partition with FUS to preserve the liquid phase against amyloid fibril formation.

Membraneless organelles contain a wide spectrum of molecular chaperones, indicating their important roles in modulating the metastable conformation and biological function of membraneless organelles. Here we report that class I and II Hsp40 (DNAJ) proteins possess a high ability of phase separation rendered by the flexible G/F-rich region. Different Hsp40 proteins localize in different membraneless organelles. Specifically, human Hdj1 (DNAJB1), a class II Hsp40 protein, condenses in ubiquitin (Ub)-rich nuclear bodies, while Hdj2 (DNAJA1), a class I Hsp40 protein, condenses in nucleoli. Upon stress, both Hsp40 proteins incorporate into stress granules (SGs). Mutations of the G/F-rich region not only markedly impaired Hdj1 phase separation and SG involvement and disrupted the synergistic phase separation and colocalization of Hdj1 and fused in sarcoma (FUS) in cells. Being cophase separated with FUS, Hdj1 stabilized the liquid phase of FUS against proceeding into amyloid aggregation in vitro and alleviated abnormal FUS aggregation in cells. Moreover, Hdj1 uses different domains to chaperone FUS phase separation and amyloid aggregation. This paper suggests that phase separation is an intrinsic property of Hsp40 proteins, which enables efficient incorporation and function of Hsp40 in membraneless organelles and may further mediate the buildup of chaperone network in membraneless organelles.

This study offers a new method for measuring polarization by using advanced computer vision techniques that involve object detection and measurements of physical distances between pedestrians. Motivated by escalating political polarization around the world, and specifically by the ideological divide between secularism and political Islam in Turkey, we analyze more than 1,400 publicly available YouTube videos recorded on the streets of Turkey. From these videos, we extract and use approximately 170,000 frames that show pedestrians. The analysis detects and categorizes pedestrians based on their gender and level of religiosity by using the YOLOv5 algorithm and develops and refines two innovative distance estimation techniques for calculating the relative distances between pairs of pedestrians. Our unique technical approach allows us to convert the 2D distances in the street videos into 3D relative distances between pedestrians of different genders and levels of religiosity. These distances are then used as a proxy for measuring the extent of polarization. The study concludes that social factors significantly influence these distances, with individuals from similar backgrounds (i.e., religious people, religious females, and non-religious females) tending to walk closer to their in-group. The greatest distances are measured between non-religious males and religious females, as well as between religious females and non-religious males, reflecting traditional gender boundaries in predominantly Muslim communities and highlighting how religious and cultural norms shape social interactions. The image dataset we have assembled stands as the most extensive collection of thematic street imagery found in computational social science research and represents the largest dataset ever gathered for analyzing political polarization in Turkey.

Subcellular membrane-less organelles consist of proteins with low complexity domains. Many of them, such as hnRNPA1, can assemble into both a polydisperse liquid phase and an ordered solid phase of amyloid fibril. The former mirrors biological granule assembly, while the latter is usually associated with neurodegenerative disease. Here, we observe a reversible amyloid formation of hnRNPA1 that synchronizes with liquid–liquid phase separation, regulates the fluidity and mobility of the liquid-like droplets, and facilitates the recruitment of hnRNPA1 into stress granules. We identify the reversible amyloid-forming cores of hnRNPA1 (named hnRACs). The atomic structures of hnRACs reveal a distinct feature of stacking Asp residues, which contributes to fibril reversibility and explains the irreversible pathological fibril formation caused by the Asp mutations identified in familial ALS. Our work characterizes the structural diversity and heterogeneity of reversible amyloid fibrils and illuminates the biological function of reversible amyloid formation in protein phase separation. Low complexity (LC) domains can drive the formation of both amyloid fibrils and protein droplets. Here, the authors identify reversible amyloid cores from the LC of hnRNPA1, based on which they elucidate the structural basis of reversible fibrillation and its interplay with hnRNPA1 droplet formation.

The infant gut microbiota undergoes significant changes in the first two years of life in response to changes in the diet. The discontinuation of the milk-based diet of the first year and the introduction of solid foods in the second year of life results in a decline in , a shift from infant strains of to adult strains which preferentially metabolize oligosaccharides derived from plants rather than from milk, a surge in short chain fatty acids such as acetic, propionic and butyric acid from newly acquired commensal , and the transformation of primary bile acids into secondary bile acids by a limited number of newly acquired and highly specialized spp. By 3 years of age, diet and gut microbiota closely resemble those of adults. Gut bacteria required for the production of SCFAs and secondary BAs are potential targets for the intervention of microbiome-related diseases.