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Achieving efficient circularly polarized white organic light‐emitting diode (CP‐WOLED) remains a significant challenge. In this study, a proof‐of‐concept for realizing CP‐WOLED is proposed using an electroplex emission strategy between a chiral thermally activated delayed fluorescence (TADF) emitter and hole‐transporting material. A series of chiral polymers (R/S)‐E‐x (x = 0.02, 0.05, and 0.1) are designed and prepared via random copolymerization of a chiral chromophore and styrene moiety, which shows typical TADF character. The neat film of (R/S)‐E‐0.1 presents distinct chiroptical properties with a dissymmetry factor (|glum|) of 2.8 × 10−3. Notably, solution‐processable, single‐emitting‐layer CP‐WOLEDs are fabricated using these chiral polymers in combination with 1,1‐bis[(di‐4‐tolylamino)phenyl]cyclohexane (TAPC) as the emitter, achieving a record maximum external quantum efficiency of 15.1% and Commission Internationale de lʹeclairage coordinate of (0.36, 0.40). Importantly, these CP‐WOLEDs exhibit an impressive |gEL| value of 2.4 × 10−3. This research provides a straightforward and effective strategy for the realization of high‐performance CP‐WOLED. [ABSTRACT FROM AUTHOR]

With the increasing energy demand and growing concern about greenhouse gases emissions from fossil fuel combustion, converting the ocean wave energy into the electrical energy has emerged as a promising and sustainable solution. This paper proposes a novel floating ocean wave energy harvester based on the fiber-constrained dielectric elastomer generator (DEG) arrays and investigates the energy harvesting (EH) performance of the fiber-constrained DEG embedded into the harvester. A theoretical analysis model of the fiber-constrained DEG describing the free relaxation process is developed and verified by the existing experimental data. On this basis, the electrical energy and conversion efficiency of the fiber-constrained DEG are comprehensively analyzed under diverse system parameters, aiming to explore the feasible methods for performance improvement. Results show that both the electrical energy and conversion efficiency are enhanced by shortening the cycle period, boosting the output voltage, and increasing the time ratio of the rising segment in a cycle period. Variations of the electrical energy and conversion efficiency with the input voltage exhibit the non-monotonic behavior. In addition, at low input voltage, enlarging the maximum stretch ratio improves the EH performance, while at high input voltage, the overlarge maximum stretch ratio goes against the performance improvement. The average output power of the harvester with different lengths of rods in its displacement magnifying mechanism is also investigated. Results show increasing the rod length can improve the average output power. In addition, results can help to provide a guidance for designing a high-performance DE-based floating wave energy harvester. [ABSTRACT FROM AUTHOR]

The Huangjindong gold deposit in northeastern Hunan is one of the most representative gold deposits in the Jiangnan Orogenic Belt. The orebodies are mainly hosted in the Neoproterozoic Lengjiaxi Group, which comprises carbonaceous slates. Abundant carbonaceous material (CM) can be found in the host rocks and ore-bearing quartz veins, but its geological characteristics and genesis, as well as its association with gold mineralization, are still unclear. Systematic petrographic observation demonstrated two types of CM in host rocks and ores, i.e., CM1 and CM2. Among them, CM1 is the predominant type and mainly occurs in the layered carbonaceous slates, while CM2 is mostly present in quartz veins and mineralized host rocks. Laser Raman spectroscopic analyses of CM1 were performed at higher temperatures (376–504 °C), and CM2 was generated at similar temperatures (255–435 °C) to gold mineralization. Combined with previous studies, we can conclude that CM1 was produced by Neoproterozoic to early Paleozoic metamorphism before gold mineralization, while CM2 is of hydrothermal origin. Geochemical modeling indicates that CM1 could promote gold precipitation through reduction, as well as facilitate structure deformation and metal absorption as previously proposed. However, hydrothermal CM2 is favorable for gold mineralization because it triggers sulfidation, similar to other Fe-bearing minerals (such as siderite) in the host rocks. Consequently, both types of CM in the Huangjindong deposit are favorable for gold mineralization and carbonaceous slates could be important gold-bearing units for future ore prospecting in the Jiangnan Orogen as well as other places in South China. [ABSTRACT FROM AUTHOR]

A new design of a flexible and compact electrostatic generator with dielectric fluid is presented in this work. The generator utilizes the flow of dielectric fluid between two dielectric films to change the capacitance and converts mechanical energy into electrical energy. We fabricate a dielectric fluid generator (DFG) and build up an experimental setup to investigate the performance of energy harvesting. We use an optimal triangular electromechanical cycle and achieve a maximum energy harvesting power of 1.83 mW with a device that the length of the longest side is 15 cm. The power density is 35.2 μW g−1, and the conversion efficiency is 17.8%. The parameters of the DFG, including the initial voltage, the applied force, and the mechanical loading time, are studied. As a demonstration, we use the DFG to harvest electrical energy from hand tapping to power LEDs. The DFG is flexible and compact, which is promising for harvesting energy from human movements. [ABSTRACT FROM AUTHOR]

As a central topic in Behavioral Ecology, animal space use involves dynamic responses to social and ecological factors. We collared 22 rhesus macaques (Macaca mulatta) from six groups on Neilingding Island, China, and collected 80,625 hourly fixes over a year. Using this high‐resolution location data set, we quantified the macaques' space use at the individual level and tested the ecological constraints model while considering various environmental and human interfering factors. As predicted by the ecological constraints model, macaques in larger groups had longer daily path lengths (DPLs) and larger home ranges. We found an inverted U‐shape relationship between mean daily temperatures and DPLs, indicating that macaques traveled farther on mild temperature days, while they decreased DPLs when temperatures were too high or too low. Anthropogenic food subsidies were positively correlated to DPLs, while the effect of rainfall was negative. Macaques decreased their DPLs and core areas when more flowers and less leaves were available, suggesting that macaques shifted their space use patterns to adapt to the seasonal differences in food resources. By applying GPS collars on a large number of individuals living on a small island, we gained valuable insights into within‐group exploitation competition in wild rhesus macaques. Highlight: By applying GPS collars, we assessed home range quality and space utilization for 22 rhesus macaques in six groups.Our results offered supportive evidence for the ecological constraints model, indicating that within‐group exploitation feeding competition is the predominant factor influencing macaques' space use on Neilingding Island. [ABSTRACT FROM AUTHOR]

The construction and operation of large airports typically result in noticeable ground subsidence. Therefore, regular monitoring of surface deformation is essential to ensure the safe operation and maintenance of airports. However, limited research has been conducted on geological subsidence in the vicinity of the Beijing Daxing International Airport (BDIA)—completed and operating since 2019—and the surface deformation following its operational phase. Here, time series interferometric synthetic aperture radar (TS‐InSAR) was performed using Sentinel‐1A data to investigate the BDIA temporal and spatial ground displacement before, July 2017 to June 2019, and after, August 2019 to April 2020, operations. The results revealed significant ground surface deformation in the airport and its surrounding areas before operations. The maximum deformation velocity recorded here reached −70 mm/year with the areas experiencing deformation primarily being the cargo and maintenance areas, with the largest cumulative deformations reaching 115 and 80 mm, respectively. Additionally, a noticeable deformation was observed in the northern part of the airport work area, whereas the airport terminal and four runways remained relatively stable. After completion, substantial ground subsidence persisted in both the airport and its surrounding regions, with the maximum deformation velocity exceeding −70 mm/year. The abandoned mounds to the east of the cargo area and south of the maintenance area exhibited continuous subsidence, with maximum cumulative deformations exceeding 60 and 50 mm, respectively. However, the work area, terminal, and four airport runways exhibited relative stability. These results hold substantial practical value, offering valuable insights into airport management and ensuring safe and efficient airport operations. [ABSTRACT FROM AUTHOR]

This study aims to explore the formation mechanism of starch structure and the relationships between the appearance quality and starch structure of soft rice under different nitrogen levels. We comprehensively investigated the physiological aspects, starch structure variations, and appearance quality of soft rice in response to different nitrogen applications. The results showed that under the moderate nitrogen application (270 N), the soft rice exhibited the highest AGPase activity, the highest large‐starch granule content, and the lowest chalkiness. Under the highest nitrogen application (360 N), the soft rice exhibited the highest GBSS and DBE activity and the lowest SBE activity, the highest content of long‐branched amylopectin, the lowest relative crystallinity, the fewest ordered structures, the most amorphous structures, the largest semi‐crystalline lamellar thicknesses, and the highest transparency of chalk‐free rice. In conclusion, moderate nitrogen fertilization (270 N) improved the AGPase activity, which leaded to fuller starch granules and more compact endosperm in soft rice. Thus, the grain chalkiness of soft rice decreased. Continuous nitrogen application (0‐360 N) constantly increased the GBSS and DBE activity and reduced the SBE activity in soft rice, leading a lower content of short‐branched amylopectin and a higher content of long‐branched amylopectin in soft rice. Thus, the relative crystallinity and ordered structures of soft rice were reduced. These structures improved the transparency phenotype of soft rice. [ABSTRACT FROM AUTHOR]

Backgrounds: Sleep disturbances are prevalent among elderly individuals. While polysomnography (PSG) serves as the gold standard for sleep monitoring, its extensive setup and data analysis procedures impose significant costs and time constraints, thereby restricting the long-term application within the general public. Our laboratory introduced an innovative biomarker, utilizing artificial intelligence algorithms applied to PSG data to estimate brain age (BA), a metric validated in cohorts with cognitive impairments. Nevertheless, the potential of exercise, which has been a recognized means of enhancing sleep quality in middle-aged and older adults to reduce BA, remains undetermined. Methods: We conducted an exploratory study to evaluate whether 12 weeks of moderate-intensity exercise can improve cognitive function, sleep quality, and the brain age index (BAI), a biomarker computed from overnight sleep electroencephalogram (EEG), in physically inactive middle-aged and older adults. Home wearable devices were used to monitor heart rate and overnight sleep EEG over this period. The NIH Toolbox Cognition Battery, in-lab overnight polysomnography, cardiopulmonary exercise testing, and a multiplex cytokines assay were employed to compare pre- and post-exercise brain health, exercise capacity, and plasma proteins. Results: In total, 26 participants completed the initial assessment and exercise program, and 24 completed all procedures. Data are presented as mean [lower 95% CI of mean, upper 95% CI of mean]. Participants significantly increased maximal oxygen consumption (Pre: 21.11 [18.98, 23.23], Post 22.39 [20.09, 24.68], mL/kg/min; effect size: −0.33) and decreased resting heart rate (Pre: 66.66 [63.62, 67.38], Post: 65.13 [64.25, 66.93], bpm; effect size: −0.02) and sleeping heart rate (Pre: 64.55 [61.87, 667.23], Post: 62.93 [60.78, 65.09], bpm; effect size: −0.15). Total cognitive performance (Pre: 111.1 [107.6, 114.6], Post: 115.2 [111.9, 118.5]; effect size: 0.49) was significantly improved. No significant differences were seen in BAI or measures of sleep macro- and micro-architecture. Plasma IL-4 (Pre: 0.24 [0.18, 0.3], Post: 0.33 [0.24, 0.42], pg/mL; effect size: 0.49) was elevated, while IL-8 (Pre: 5.5 [4.45, 6.55], Post: 4.3 [3.66, 5], pg/mL; effect size: −0.57) was reduced. Conclusions: Cognitive function was improved by a 12-week moderate-intensity exercise program in physically inactive middle-aged and older adults, as were aerobic fitness (VO2max) and plasma cytokine profiles. However, we found no measurable effects on sleep architecture or BAI. It remains to be seen whether a study with a larger sample size and more intensive or more prolonged exercise exposure can demonstrate a beneficial effect on sleep quality and brain age. [ABSTRACT FROM AUTHOR]