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Copper (Cu)‐based thermoelectric (TE) materials have attracted great attention from both scientific and industrial societies, but for a long time, their real applications are greatly limited by the lack of high‐performance n‐type Cu‐based TE materials. Most recently, the novel n‐type Cu‐based TE material, CuIn5Se8, has been discovered to show a record‐high TE figure‐of‐merit (zT) to match the state‐of‐the‐art p‐type Cu‐based TE materials. However, the physical origin of such high zT is still unclear due to its complex phase compositions and crystal structures. In this work, it is revealed that the excellent TE performance is mainly contributed by the intrinsically ultralow lattice thermal conductivity originating from the unique all‐scale hierarchical architecture. It covers the ranges from atomic‐scale cation disorder in the tetragonal CuIn5Se8 phase and nanoscale diversified stacking units and stacking sequences in the hexagonal CuIn5Se8 phase, to mesoscale grain boundaries between the tetragonal phase and hexagonal phase. Doping Br at the Se‐sites can largely tune the electrical transports of CuIn5Se8 while maintaining the ultralow lattice thermal conductivity, leading to high zT reaching the optimal value predicted by the single parabolic model. This work will guide the investigation of n‐type Cu‐based TE materials in the future. [ABSTRACT FROM AUTHOR]

Low Pt utilization and intense carbon corrosion of cathode catalysts is a crucial issue for high‐efficiency proton exchange membrane fuel cells due to the highly demanded long‐term durability and less acquisition/application cost. Herein, structurally tunable graphitized mesoporous carbon (GMC) is obtained by direct high‐temperature pyrolysis and in situ‐controlled mesopore formation; the structure‐optimized GMC1300‐1800 exhibits a mesopore size of 7.54 nm and enhanced corrosion resistance. Functionalized GMC1300‐1800 is loaded with small‐sized Pt nanoparticles (NPs) (1.5 nm) uniformly by impregnation method to obtain Pt/GMC1300‐1800 and form an "internal platinum structure" to avoid sulfonic acid groups poisoning as well as ensure O2/proton accessibility. Hence, the electrochemically active surface area (ECSA) of Pt/GMC1300‐1800 reaches 106.1 m2 g−1Pt, while mass activity and specific activity at 0.9 V are 2.1 and 1.4 times those of commercial Pt/C, respectively. Notably, the ECSA decay is less than 17% for both 30 000 cycles' accelerated durability tests (ADTs) of Pt attenuation and carbon attenuation. Accordingly, the optimized mesoporous structure of GMC1300‐1800 significantly decreases the coverage of sulfonic acid groups on Pt NPs, leading to the highest peak power density in the single‐cell test. Density functional theory calculations demonstrate the synergistic effect between graphitization and mesoporosity on enhancing the accessibility and durability of the catalysts. [ABSTRACT FROM AUTHOR]

Strain sensors that can rapidly and efficiently detect strain distribution and magnitude are crucial for structural health monitoring and human–computer interactions. However, traditional electrical and optical strain sensors make access to structural health information challenging because data conversion is required, and they have intricate, delicate designs. Drawing inspiration from the moisture-responsive coloration of beetle wing sheaths, we propose using Ecoflex as a flexible substrate. This substrate is coated with a Fabry–Perot (F–P) optical structure, comprising a "reflective layer/stretchable interference cavity/reflective layer", creating a dynamic color-changing visual strain sensor. Upon the application of external stress, the flexible interference chamber of the sensor stretches and contracts, prompting a blue-shift in the structural reflection curve and displaying varying colors that correlate with the applied strain. The innovative flexible sensor can be attached to complex-shaped components, enabling the visual detection of structural integrity. This biomimetic visual strain sensor holds significant promise for real-time structural health monitoring applications. [ABSTRACT FROM AUTHOR]

High‐refractive index glasses with ultra‐high Young's modulus and superior hardness have significant application in optical lenses. Research indicates that high‐entropy glasses, enriched with high dissociation energy and high‐field strength components, enhance the mechanical properties of glass. In this study, we tailored high‐entropy glasses to achieve superior optical and mechanical attributes by optimizing heavy metal oxide components and adjusting the Al2O3 content. The resultant 10RE2O3‐10Gd2O3‐32Al2O3‐36Ta2O5‐12ZrO2 (RE = La, Tm, Lu) glass demonstrates a refractive index of 2.028, a Young's modulus of 186.2 GPa, and a Vickers hardness of 9.18 GPa. The glass was colorless and widely transparent, in the visible‐to‐infrared region from 312.5 to 6674 nm, and the maximum transmittance reach up to 79.3%. These results indicate that the 10RE2O3‐10Gd2O3‐32Al2O3‐36Ta2O5‐12ZrO2 glass would be useful for camera and detector lenses. [ABSTRACT FROM AUTHOR]

In this work, we report the ternary Cu-based chalcogenide, Cu2TiTe3, as a promising thermoelectric material in middle-temperature range. The bonding interaction between Te p and Ti d states is observed in the Ti–Te octahedron, which drives the side bands up converging with Γ band, yielding a high valence band degeneracy of 5. A high electronic quality factor of 2.2 μW cm−1 K−2 and a decent power factor of 7.5 μW cm−1 K−2 at 300 K are achieved for Cu2TiTe3. Likewise, Cu2TiTe3 demonstrates low lattice thermal conductivity throughout the measured temperature range, which is attributed to the low frequency vibration related to the global motion of Ti–Te–Cu clusters. Finally, a maximum figure-of-merit of 0.38 was obtained for Cu2TiTe3 at 600 K. [ABSTRACT FROM AUTHOR]

In this work, we report the ternary Cu-based chalcogenide, Cu2TiTe3, as a promising thermoelectric material in middle-temperature range. The bonding interaction between Te p and Ti d states is observed in the Ti–Te octahedron, which drives the side bands up converging with Γ band, yielding a high valence band degeneracy of 5. A high electronic quality factor of 2.2 μW cm−1 K−2 and a decent power factor of 7.5 μW cm−1 K−2 at 300 K are achieved for Cu2TiTe3. Likewise, Cu2TiTe3 demonstrates low lattice thermal conductivity throughout the measured temperature range, which is attributed to the low frequency vibration related to the global motion of Ti–Te–Cu clusters. Finally, a maximum figure-of-merit of 0.38 was obtained for Cu2TiTe3 at 600 K. [ABSTRACT FROM AUTHOR]

1 at% Ce3+-doped Gd3Ga2Al3O12 (GGAG) single crystals were grown by an optical floating zone (OFZ) method and a traveling solvent floating zone (TSFZ) method. To reveal their structure and chemical composition homogeneity, X-ray diffraction (XRD) and high-resolution inductively coupled plasma atomic emission spectrometry (ICP-AES) were conducted on the as-grown Ce:GGAG crystals at 4 different positions along the growth direction. Compared with the Ce:GGAG crystals grown by the OFZ method (Ce:GGAG-OFZ), the Ce:GGAG crystals grown by the TSFZ method (Ce:GGAG-TSFZ) presented better Ce3+ distribution homogeneity which varied from 0.21 to 0.29 at%. However, the segregation coefficient of Ce3+ in Ce:GGAG-OFZ was found to be higher than that in Ce:GGAG-TSFZ, revealing a different solidification rate between them. The comparison study shows that the photoluminescence (PL) intensity of Ce:GGAG-TSFZ is about twice higher than that of Ce:GGAG-OFZ and the maximum light yield (LY) of 35 340 photons per MeV also occurs in the former. Trap depths were measured to be 0.70 eV and 0.98 eV by TL glow curves. The LY value of Ce:GGAG-TSFZ along the growth direction fluctuated to a lesser extent with respect to that of Ce:GGAG-OFZ; the latter decreases gradually along the growth direction. It is concluded that the TSFZ method helps to improve the homogeneity of crystal composition when growing crystals with multiple compositions or incongruent compounds. [ABSTRACT FROM AUTHOR]

Eu3+-doped GdAlO3 (Eu:GAP) and Gd0.5La0.5AlO3 (Eu:GLAP) perovskite single crystals were successfully grown using the optical floating zone (OFZ) method. The microstructure, optical, photoluminescence (PL) and radioluminescence (under X-ray excitation, XEL) were investigated. Under the PL excitation of 275 nm, obvious emission bands peaking at 556 nm, 592 nm, 617 nm, 625 nm, 655 nm, and 706 nm were demonstrated, which correspond to the 5D0 → 7Fj (j = 0–4) transitions of Eu3+. The grown Eu:GAP single crystal showed a stronger PL intensity compared with that of Eu:GLAP in the red light region. After annealing at 1000 °C for 4 h in weak reductive atmosphere (Ar + 5% H2), a slight redshift and dramatic enhancement of PL and XEL intensity occurred. In addition, Eu:GLAP show a more intense XEL emission than that of Eu:GAP. Considering their different densities, these two kinds of red luminescence phosphors are proposed to be promising in a wide field of X-ray imaging, warm white, or plant lighting, respectively. [ABSTRACT FROM AUTHOR]

Ce3+, Pr3+ co-doped Lu3Al5O12 (Ce, Pr:LuAG) single crystals and ceramics were prepared using the optical floating zone (OFZ) and reactive vacuum sintering methods, respectively. The microstructure, photo- (λex = 450 nm), and radio-luminescence (under X-ray excitation) performance, as well as scintillation light yield (LY, under γ-ray, 137Cs source) of both materials, were investigated and compared. Ce, Pr:LuAG ceramics had an in-line transmittance of approximately 20% in the visible light range, while the analogous crystals were more transparent (~65%). The X-ray excited luminescent (XEL) spectra showed the characteristic Ce 3+ and Pr3+ emissions located at 310 nm, 380 nm, and 510 nm. The highest LY of the Ce, Pr:LuAG ceramics reached 34,112 pho/MeV at 2 μs time gate, which is higher than that of a single crystal. The ratio of LY values (LY2/LY0.75) between shaping times of 0.75 μs and 2 μs indicated a faster scintillation decay of ceramics regarding single crystals. It was ascribed to the lower effective concentration of luminescent activators in single crystals because of the coefficient segregation effect. [ABSTRACT FROM AUTHOR]

Today solid-state cooling technologies below liquid nitrogen boiling temperature (77 K), crucial to quantum information technology and probing quantum state of matter, are greatly limited due to the lack of good thermoelectric and/or thermomagnetic materials. Here, we report the discovery of colossal Nernst power factor of 3800 × 10−4 W m−1 K−2 under 5 T at 25 K and high Nernst figure-of-merit of 71 × 10−4 K−1 under 5 T at 20 K in topological semimetal NbSb2 single crystals. The observed high thermomagnetic performance is attributed to large Nernst thermopower and longitudinal electrical conductivity, and relatively low transverse thermal conductivity. The large and unsaturated Nernst thermopower is the result of the combination of highly desirable electronic structures of NbSb2 having compensated high mobility electrons and holes near Fermi level and strong phonon-drag effect. This discovery opens an avenue for exploring material option for the solid-state heat pumping below liquid nitrogen temperature. Today solid-state cooling technologies below 77 K are greatly limited. Here, the authors report the colossal Nernst power factor in NbSb2 single crystal, providing a high performance thermomagnetic material for solid-state cooling at low temperature. [ABSTRACT FROM AUTHOR]

SrAl2O4:Eu2+, Dy3+ has been widely studied as a classical persistent phosphor due to its stability and long green-afterglow duration. In this study, a series of Ce3+ co-doped SrAl2O4:Eu2+, Dy3+ phosphors were prepared by the traditional solid state reaction method, sintering under Ar + 5% H2 atmosphere in the temperature range of 1300–1500°C. The effect of Ce3+ co-doping on luminescence performance of SrAl2O4:Eu2+, Dy3+ was investigated at Ce3+ concentration of 0–0.3 at %. Under excitation wavelengths of 365, 400 and 460 nm, respectively, the luminescence intensity was found to increase linearly with rise of sintering temperature or Ce3+ doping concentrations. It was ascribed to the sufficient crystallization at high sintering temperature as well as the high absorption cross section of Ce3+ ion. Besides, the Ce3+ co-doping speeds up the afterglow time without introducing the emission wavelength shift. Therefore, Ce3+ co-doped SrAl2O4: Eu, Dy is a promising high efficient phosphor for compensated the dark period in alternating current driven light-emitting diodes (AC-LED) lighting. [ABSTRACT FROM AUTHOR]

Cervical cancer is the fourth most prevalent cancer type among all malignancies, so it is of great significance to find its actual pathogenesis mechanisms. In the present study, 90 women were enrolled, and high-throughput sequencing technology was firstly used to analyze the vaginal microbiota of healthy women (C group), cervical intraepithelial neoplasia patients (CIN group) and cervical cancer patients (CER group). Our results indicates that compared with C group, a higher HPV infection rate as well as increased Neutrophil ratio and tumor marker squamous cell carcinoma antigen (SCCA) were obtained, and a decrease in Lymphocyte ratio and Hemoglobin were also present. In addition, the cervical cancer showed a strong association with reduced probiotics Lactobacillus , increased pathogens Prevotella spp., Sneathia spp. and Pseudomonas spp. These results prove that the immunological changes generated by the cervical cancer and the vaginal microbiota can interact with each other. However, further study investigating the key bacteria for cervical cancer is still needed, which can be a clue for the diagnosis or treatment of cervical cancer. [ABSTRACT FROM AUTHOR]

Present study characterized five Escherichia coli co-expressing ESBL and MCR-1 recovered from food, food-producing animals, and companion animals in China. Antimicrobial susceptibility tests, conjugation experiments, and plasmid typing were performed. Whole genome sequencing (WGS) was undertaken for all five isolates using either PacBio RS II or Illumina HiSeq 2500 platforms. The cefotaxime and colistin resistance encoded by bla CTX–M and mcr-1 genes, respectively, was transferable by conjugation either together or separately for all five strains. Interestingly, the ESBL and mcr-1 genes could be co-selected by cefotaxime, while the colistin only selected the mcr-1 -carrying plasmids during the conjugation experiments. Five E. coli sequence types (ST88, ST93, ST602, ST162, and ST457) were detected. Although diverse plasmid profiles were identified, IncI2, IncFIB, and IncFII plasmid types were predominant. These five clonally unrelated isolates harbored the mcr-1 gene located on similar plasmid backbones, which showed high nucleotide similarity to plasmid pHNSHP45. The mcr-1 gene can be co-transmitted with bla CTX–M genes through IncI2 plasmids with or without IS Apl1 in our study. Characterization of these co-existence ESBL and mcr-1 isolates extends our understanding on the dissemination of these resistance markers among bacteria of diverse origins. [ABSTRACT FROM AUTHOR]

Highly active Pt‐based intermetallic nanoparticles (i‐NPs) loaded on stable supports have garnered considerable interest as promising oxygen reduction reaction (ORR) catalysts for proton‐exchange‐membrane fuel cells (PEMFCs). Herein, thermostable tellurium (Te) is vapor‐deposited onto commercial conductive carbon to anchor high‐temperature‐synthesized Pt3Co i‐NPs. Advanced characterization and density functional theory (DFT) calculations demonstrate that the binding energy of Pt 4f and Co 2p shift positively by 0.12 and 0.95 eV after the introduction of Te in carbon support, promoting the formation of Pt─Te bonds, which enhances the metal–support interactions (MSIs) in Pt3Co/Te‐C (with a more negative binding energy of −10.28 eV). The average size of well‐dispersed Pt3Co i‐NPs (≈3.9 nm) on Te─C is considerably smaller than that of Pt3Co i‐NPs (≈9.1 nm) on commercial carbon. The specific activity of Pt3Co/Te‐C decreases by only 1.5% after 100,000 ultra‐long voltage‐accelerated cycles, while the morphology remains almost unchanged. The membrane electrode assembly using Pt3Co/Te‐C as a cathode demonstrates impressive activity (power density of 2.32 W cm−2@4 A cm−2 and mass activity of 0.50 A mgPt−1@0.9 V) and robust durability (mass activity@0.9 V loss of 26% after 30,000 cycles with intact L12 ordered structure) in H2–O2 operation, significantly exceeding the DOE 2025 requirements. [ABSTRACT FROM AUTHOR]

Cisplatin resistance is the main cause of postoperative recurrence and difficulty in the treatment of ovarian cancer. It is urgently needed to identify therapeutic drugs with unique functions to overcome the current challenges in the treatment of ovarian cancer. In this study, we found that TG promoted the accumulation of ROS and MDA in A2780/DDP cells and downregulated the expression of key antioxidant molecules. In vivo, the survival rate of tumor-bearing nude mice was prolonged by TG without significant hepatotoxic reaction. The expression of key antioxidant molecules in tumor tissues was consistent with that in vitro. These findings revealed that TG disrupted homeostasis of redox reactions and induced ferroptosis in A2780/DDP cells, thereby enhancing cisplatin chemosensitivity of ovarian cancer. Overall, TG may be a novel potential therapeutic option for reversing resistance to cisplatin chemotherapy. • Tripterygium glycosides exacerbated the intracellular oxidative stress. • The NRF2/GPX4 signaling axis is disrupted by tripterygium glycosides. • The chemosensitivity of cisplatin was enhanced by tripterygium glycosides. • Tripterygium glycosides is a potential inducer of ferroptosis in cancer cells. [ABSTRACT FROM AUTHOR]

Shale gas is an important unconventional natural gas resource existing in shale reservoir with huge reserves. Due to the ultralow porosity and permeability, it requires the horizontal well drilling and the multi-stage hydraulic fracturing technology to successfully produce the shale gas. The accurate prediction of shale gas production is crucial to the reasonable design of the development plan. However, due to the complex hydraulic fracture network and the gas flow mechanism, the physics-based shale gas production prediction model is still under way. The data-driven model provide an alternative way to deal with the production prediction problem. The multi-objective random forest method is proposed to predict the dynamic production data. The geological and hydraulic fracturing properties are used as input feature. Its prediction performance is evaluated based on the R squared values after determining the appropriate hyper-parameters. The ranking of variable importance can be helpful to improve the interpretability of the data-driven model. The initial peak production rate before declining can be also used as an additional input feature. With the initial peak production rate augmented into the feature set, it can greatly improve the prediction of shale gas production. The variable importance analysis results show that it can be the most influencing factor to prediction accuracy and the ranking of other factors can be altered significantly. The performance of multi-objective random forest (MORF) and multi-output regression chain (MORC) methods are compared, and the comparison result indicates MORC requires a relatively smaller random forest structure, but the prediction performance of MORF is better than MORC. More sample data with less measurement errors can increase the accuracy of the data-driven shale gas production model but there exists a threshold value to improve the accuracy gain. • A data-driven shale gas production model can be built through the multi-objective random forest method. • Variable importance analysis can improve the interpretability of the data-driven shale gas production model. • The multi-objective random forest method can deal with correlated shale gas production data. • It is helpful to collect more data with less measurement errors to build the data-driven model. [ABSTRACT FROM AUTHOR]