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We demonstrate a high-power 2.0-μm fiber laser system delivering femtosecond pulses with a fundamental repetition rate of >10 GHz, the highest value so far, to the best of our knowledge. The seed is a self-started fundamentally mode-locked Tm-doped fiber laser that has excellent power and spectral stabilities. The laser system can provide an average power of >600 mW, and the use of soliton-effect-based pulse compression allows the achievement of a pulse duration of 163 fs, leading to a compression factor of ∼ 13. It is anticipated that this new high-power femtosecond fiber laser with a 10-GHz-level fundamental repetition rate can serve as a promising light source for various applications, including laser surgery, micromachining, frequency comb spectroscopy, and nonlinear frequency conversion.

Bismuth telluride (Bi2Te3) has attracted much attention in the field of thermoelectrics since it is one kind of commercial room-temperature thermoelectric material. Herein three kinds of Bi2Te3 thermoelectric fibers with internal tensile stress are fabricated utilizing an optical fiber template method. The effects of internal stress on the microstructure and the electrical transportation of Bi2Te3 thermoelectric fibers are investigated. The Bi2Te3 cores in the fibers are highly crystalline and possess a tensile nanosheet structure with preferential orientation as evidenced by X-ray diffraction and Raman studies. Tensile stress can enhance electrical properties of the fibers. And a paper cup generator covered with 20 pieces of optimized fibers provides a μW-level output power. It is inferred that tensile stress tuning can be an effective tool for the material optimization of thermoelectric performance.

A conventional large-area indirect-conversion X-ray detector usually adopts front side illumination (FSI) of a scintillator atop a photodiode-integrated thin-film transistor (TFT) array. This work however proposes a backside illuminated (BSI) three-dimensional dual-gate photosensitive a-Si:H TFT (3-D DGTFT) on a scintillating glass substrate, aiming for indirect-conversion X-ray detection. It not only improves the sensitivity with a 3-D photosensitive TFT as an active pixel sensor, but also enhances the resolution and photon utilization by reducing photon scattering and optical crosstalk. Backside illumination of 3-D photosensitive TFT-integrated scintillating glass therefore provides an alternative approach to large-area indirect-conversion X-ray imaging.

Photonic topological insulators (PTIs) bring markedly new opportunities to photonic devices with low dissipation and directional transmission of signal over a wide wavelength range due to the broadband topological protection. However, the maximum gap/mid-gap ratio of PTIs is below 10% and hardly further improved duo to the lack of new bandwidth enhancement mechanism. In this paper, a PTI with the gap/mid-gap ratio of 16.25% is proposed. The designed PTI has a honeycomb lattice structure with triangular air holes, and such a wide bandwidth is obtained by optimizing the refractive-index profile of the primitive cell for increasing the energy proportion in the geometric perturbation region. The PTI shows a large topological nontrivial gap (the gap/mid-gap ratio 33.4%) with the bandwidth approaching its theoretical limit. The edge states propagate smoothly around sharp bends within 1430–1683 nm. Due to topological protection, the bandwidth only decreases 1.38% to 1450–1683 nm under 1%-random-bias disorders. The proposed PTI has a potential application in future high-capacity and nonlinear topological photonic devices.

On its 125th anniversary edition, the journal, Science , listed “what is the nature of the glassy state?” as one of the 125 most challenging scientific issues facing modern science. Predicting glass properties is challenging because of the complexity of the glassy materials, which significantly imped the development of functional glasses. At present, the development of high-performance functional glasses relies heavily on prior experience and trial-and-error, resulting in long experimental periods, high costs, and low efficiency. Materials genome engineering is expected to accelerate glass research. Based on the metastable composition diagram, this paper proposes that the neighboring congruent glassy compounds in the glass composition diagram can be regarded as glass genes. The glass-forming region of a BaO-Ga2O3-GeO2 glass system was calculated by thermodynamic method using the compound’s thermodynamic data. The properties of different glass systems were calculated using the glass gene approach, giving theoretical calculation results consistent with experimental data in the literature. Furthermore, the germanate anomaly can be predicted by the glass gene approach. This work may provide an effective way to decode the glass genome and develop functional glasses rapidly and at low cost.

The high-precision patterning of metal halide perovskites (MHPs) is of paramount importance for their device application. Here, we demonstrate the femtosecond (fs)-laser-assisted formation of three-dimensional MHP nanocrystal (NC) patterns with strong blue photoluminescence (PL) inside an oxide glass. Our strategy enables the crystallization and erasing of CsPb(Cl/Br)

Herein, we report a two-step solution-precipitation approach to synthesize perovskite CH3NH3PbBr3 polyhedral single crystals. Their formation mechanism was investigated, revealing the close relationship between reaction rate and crystallization of perovskite. Furthermore, such perovskite polyhedrons were demonstrated to be feasible for lasing with a high quality factor and for single-mode operation.

High-performance thermoelectric (TE) materials with great flexibility and stability are urgently needed to efficiently convert heat energy into electrical power. Recently, intrinsically crystalline, mechanically stable, and flexible inorganic TE fibers that show TE properties comparable to their bulk counterparts are of interest to researchers. Despite remarkable progress moving TE fibers towards room-temperature TE conversion, the figure-of-merit value (ZT) and bending stability still need enhancement. Herein, we report interfacial engineering enhanced thermoelectric properties of micro-nano polycrystalline TE fibers fabricated by thermally drawing Bi2Te3-based bulks in a glass-fiber template. The interfacial engineering effect comes from generating stress-induced oriented nanocrystals to increase electrical conductivity and producing strain-distorted interfaces to decrease thermal conductivity. The resulting fibers achieve a 40% higher ZT (~1.4 at 300 K) than their bulk counterparts and show a reversible bending radius of 50 µm, approaching the theoretical elastic limit. This fabrication strategy works for a wide range of inorganic TE materials and benefits the development of fiber-based micro-TE devices.

We report a silicate-clad heavily Tm

We investigate novel cavity solitons that arise in pulse-pumped fibre resonators in the presence of desynchronisation and stimulated Raman scattering. The solitons possess numerous advantageous characteristics and could enable novel route to ultrafast pulses.

Rare-earth (RE) ions doped laser glass has attracted the interest of many researchers because of its numerous potential applications in planar waveguides and fiber lasers. In this work, the 2-µm and upconversion luminescence properties of Ho3+ are simultaneously enhanced through the design of components used to regulate the network structure of the germanate glass. Furthermore, the thermal, structural, and spectroscopic properties of the Ho3+/Yb3+ co-doped germanate laser glass are systematically investigated. It is noted that the calculated gain coefficient of the Nb2O5 modified germanate laser glass can reach as high as 3.05 cm−1 at 2047 nm. These results suggest that the prepared germanate laser glass with superior performances is a promising candidate for 2-µm mid-infrared laser materials applications.

Potato, a vegetable crop grown worldwide, has many uses, a short growth period, a large market demand and high economic benefits. The loss of potato seediness due to traditional potato growing methods is becoming increasingly evident, and research on new ways of growing potatoes is particularly important. Bud planting technology has the advantages of more reproduction, faster growth, and simplified maintenance of crop plants under cultivation.In this study, a bud planting method was adopted for the cultivation of potato seedlings. Specifically, we assessed different types of treatments for the production of high-quality buds and seedlings of potato. A total of four disease-free potato varieties (Fujin, Youjin, Zhongshu 4, and Feiwuruita) were selected, potato buds with three different lengths (3 cm, 5 cm, and 7 cm) were considered the TCultivation of seedlings from potato buds of different lengths increased the reproduction coefficient and reduced the number of seed potatoes needed for cultivation. All morphological, physiological, and yield indices showed positive trends. A potato bud length of 7 cm was optimal for raising seedlings. Moreover, buds located at the terminal of the potato yielded seedlings with the best quality. In conclusion, we recommend that our proven bud planting technique be adopted at the commercial level, which could support good crop production with maximum yield.

Scintillators, which can convert high‐energy ionizing radiation into visible light, have been serving as the core component in radiation detectors for more than a century of history. To address the increasing application demands along with the concern on nuclear security, various strategies have been proposed to develop a next‐generation scintillator with a high performance in past decades, among which the novel approach via structure control has received great interest recently due to its high feasibility and efficiency. Herein, the concept of “structure engineering” is proposed for the exploration of this type of scintillators. Via internal or external structure design with size ranging from micro size to macro size, this promising strategy cannot only improve scintillator performance, typically radiation stopping power and light yield, but also extend its functionality for specific applications such as radiation imaging and therapy, opening up a new range of material candidates. The research and development of various types of structured scintillators are reviewed. The current state‐of‐the‐art progresses on structure design, fabrication techniques, and the corresponding applications are discussed. Furthermore, an outlook focusing on the current challenges and future development is proposed., A comprehensive overview on developing novel scintillators by structure engineering strategy, which focuses on rationally tailoring the structures with typical size spanning micro, meso, and macroranges, is provided. The state‐of‐the‐art progresses on structure design, fabrication techniques, and the corresponding applications are systematically discussed. Future perspectives focusing on current challenges are presented as well.

It has remained a big challenge to grow large crystals of compounds at very anisotropic crystal growth rates. GdPO

Nb-V-Ti-Mo complex microalloyed high-strength fire-resistant steel was obtained through two-stage hot rolling and laminar cooling. The results showed that the microstructure of the steel included bainite ferrite and martensite-austenite constituent (i.e., MA) islands. The experimental steel displayed high strength at room temperature, with a yield strength (YS) of 617 MPa and tensile strength of 813 MPa (elongation = 18.5%). As the temperature increased to 700 °C, the high-temperature yield strength gradually decreased. Electron backscatter diffraction (EBSD) was used to analyze the experimental steels at different temperatures. The grain sizes did not grow significantly. A small number of nanoprecipitates with an average diameter of 29.2 nm were distributed in the matrix of the as-rolled specimen. Upon increasing the temperature, the number of fine nanoprecipitates gradually increased, resulting in a gradual decrease in their average diameter, reaching a minimum of 19.4 nm at 600 °C. The Orowan equation explained well the precipitation strengthening effect of the nanoprecipitates that formed at a high temperature. At both room temperature and 300 °C, the Ashby work hardening theoretical curves were consistent with the experimental true stress-strain curves. Dynamic recovery and recrystallization occurred at 600 °C, which caused the experimental true stress-strain curve to deviate from the calculated curve.

Based on a fiber Fabry–Pérot tunable filter and a 3.0 m long unpumped gain fiber for forming dynamic grating, an in-band pumped tunable Tm3+-doped single-frequency fiber laser covering a wavelength tuning range from 1857.01 to 2020.17 nm and a tuning interval of −1 at frequencies over 1 MHz are obtained. To date, it is the broadest wavelength tuning range that has been reported in the 2 μm region, which is highly competitive in atmospheric detection.

Simple Summary Multidrug resistance (MDR) limits the effectiveness of colorectal cancer (CRC) treatment and miRNAs play an important role in drug resistance. To search for miRNA targets that may be involved in the CRC MDR phenotype, this study used small RNAomic screens to analyze the expression profiles of miRNAs in CRC HCT8 cell line and its chemoresistant counterpart HCT8/T cell line. It was found that miR-92b-3p was highly expressed in HCT8/T cells and chemotherapeutic drugs could stimulate CRC cells to up-regulate miR-92b-3p expression and conferred cellular resistance to chemotherapeutic drugs. This study revealed a new mechanism of MDR in CRC, elucidating for the first time the direct link between miR-92b-3p/CDKN1C and chemoresistance. In summary, this study suggested that miR-92b-3p could be used as a potential therapeutic target for reversing MDR in chemotherapy and as a candidate biomarker for predicting the efficacy of chemotherapy. Abstract Colorectal cancer (CRC) is the third most common malignant tumor in the world and the second leading cause of cancer death. Multidrug resistance (MDR) has become a major obstacle in the clinical treatment of CRC. The clear molecular mechanism of MDR is complex, and miRNAs play an important role in drug resistance. This study used small RNAomic screens to analyze the expression profiles of miRNAs in CRC HCT8 cell line and its chemoresistant counterpart HCT8/T cell line. It was found that miR-92b-3p was highly expressed in HCT8/T cells. Knockdown of miR-92b-3p reversed the resistance of MDR HCT8/T cells to chemotherapeutic drugs in vitro and in vivo. Paclitaxel (PTX, a chemotherapy medication) could stimulate CRC cells to up-regulate miR-92b-3p expression and conferred cellular resistance to chemotherapeutic drugs. In studies on downstream molecules, results suggested that miR-92b-3p directly targeted Cyclin Dependent Kinase Inhibitor 1C (CDKN1C, which encodes a cell cycle inhibitor p57Kip2) to inhibit its expression and regulate the sensitivity of CRC cells to chemotherapeutic drugs. Mechanism study revealed that the miR-92b-3p/CDKN1C axis exerted a regulatory effect on the sensitivity of CRC cells via the regulation of cell cycle and apoptosis. In conclusion, these findings showed that miR-92b-3p/CDKN1C was an important regulator in the development of drug resistance in CRC cells, suggesting its potential application in drug resistance prediction and treatment.

The controllable incorporation of the dopant element with strictly designed coordination geometry into the target host merits untold scientific and technological potential, yet it has been met with...

A passively Q-switched single-frequency fiber laser with stable multi-wavelength operation is presented in this report. The laser cavity is constructed by using a 13-mm Er 3+ /Yb 3+ co-doped phosphate fiber with a multi-channel fiber Bragg grating and a semiconductor saturable absorber mirror attached to each fiber end, respectively. Quad-wavelength pulsed lasers are obtained and all of them maintain single-frequency operation. By controlling the pump power and the temperature of laser cavity, the Q-switched pulse operation is realized with repetition rates range of 126.6-350.9 kHz, a narrowest pulse duration of 104 ns, and a maximum pulse energy of 55.4 nJ. To the best of our knowledge, this is the first study to realize a Q-switched fiber laser operating at multiple wavelengths with single longitudinal mode. Furthermore, the evolutions of the pulse energy and repetition rates for different wavelength numbers are further analysis theoretically. This type of single-frequency pulsed fiber laser has extensive application prospect in fiber sensing and lidar systems.

Multimaterial fibers which integrate novel materials and/or structures into fiber configuration aim at developing multiple functionalities and high performance. Here, we demonstrate a kind of multimaterial fibers with crystalline GeSe core and K9 glass cladding by the molten core drawing method. The as-drawn fibers undergo a change in electrical conductivity when externally illuminated by an 808 nm HeNe laser. Furthermore, the Seebeck coefficient of the fibers is comparable with bulk GeSe, while the resistance is 3–4 magnitude lower than that. The results show that the GeSe core fibers have promising applications in optical switch and thermoelectric conversion field.

A theoretical analysis of the influence of laser's linewidth on phase-OTDR sensing system is proposed and corresponding experiment is demonstrated. The linewidth factor of laser source is introduced into the signal expressions of phase-OTDR system under the nonquasi monochromatic light condition. The effect of linewidth can be transformed into an exponential decay item of the signal. Even if the sensing range is always smaller than the coherent length of the laser source, the detection SNR will decrease as the linewidth increases. A Phase-OTDR strain detection experiment with linewidth controllable laser is performed to verify the derived theoretical analysis result. The result shows that when linewidth increases from 2 kHz to 1 MHz, the detection SNR of the same vibration signal will decrease 4.3 dB. In order to select the appropriate laser source for phase-OTDR system, the coherent length and influence of linewidth ought to be taken into account to ensure the detection performance of the system.

High-power single-frequency fiber lasers with exceptional properties, such as mode-hop-free and narrower linewidths, lower noise, and compact all-fiber designs, have been attractive in many applications, including high-resolution sensing, coherent telecommunications, optical frequency domain reflectometry, and as a seed laser for light detection and ranging (LIDAR). However, the development of high-power single-frequency fiber lasers is constrained greatly by the lack of high-gain optical fiber and components. In this review, we discuss the basic considerations of advanced techniques for soft glass fiber and fiber preform as well as three key issues among them. Then, the recent advances in RE-doped soft glass and fiber lasers operating at near-infrared (NIR) and mid-infrared (MIR) wavelengths are evaluated in detail. Finally, prospects, applications and challenges for the realization of high-efficiency soft optical fibers in single-frequency fiber laser applications are analyzed and discussed. The review is organized as follows: Sections 1–3 introduce the basic requirements for the rare-earth (RE) ions and host matrix material for obtaining efficient NIR-MIR laser output, a review of the background of processing fundamentals on the fabrication and characterization for newly developed soft optical glass fibers, an outline of the key issues of platinum removal and the dehydration technique, effective doping of RE, and low splicing loss together with the recent theoretical and experimental results. Section 4 summaries the design and development of RE-doped soft optical glass and fiber lasers operating at 1, 1.5, 2, and 3 μm with emphatical discussions on the related luminescence mechanism and laser foundation as well as single-frequency lasers. Section 5 reviews the recent progress of various novel glass fibers and fiber lasers with unique photoelectricity properties, such as transparent glass-ceramic fiber and fiber lasers, quantum-dot fiber and fiber lasers, Bi-doped fiber and fiber lasers, as well as other novel glass fibers and devices, and outlines their prospects, applications, and challenges. Furthermore, Section 6 presents the conclusions of this review, which include the following: (1) From the single-component silica fiber to the multicomponent soft optical glass fiber, the glass compositions become more and more complex and the corresponding preparation method is constantly developing and improving. Various new types of optical fiber materials and components greatly expand their applications in the fields of fiber amplifiers, fiber lasers, and nonlinear optics, etc. (2) High-gain optical fiber is the key to the development of high-power single-frequency fiber lasers. To achieve intense and highly-efficient luminescence and lasers at the NIR and MIR regions from soft glass and optical fiber, the following methods were adopted, including using RE sensitization, uniform doping with high-concentration RE, hydroxyl and impurity-removing, new optical fiber and laser cavity design, low fusing loss, and the high-efficiency pumping method, etc. These novel glass systems and luminescence mechanisms enrich the glass systems of the past and provide a wealth of valuable data for optoelectronic materials and devices.

The Dirac mode in the hollow core photonic crystal fibers (HC-PCFs) traditionally rely on high refractive index glasses with a high air-filling factor. In this paper, the Dirac mode was observed in the modified honeycomb lattice HC-PCFs, which breaks the constraint of refractive index, and can be realized in pure silica glasses for the first time. The band structure of the modified honeycomb lattice was calculated to elaborate the formation process of the Dirac point. The Dirac mode in the HC-PCFs was established at the Dirac frequency outside the bandgaps. In addition, the relationship between the Dirac frequency and the air-filling fraction and the refractive index were also analyzed. This design provides a modified honeycomb lattice HC-PCFs with substantially reduced fabrication effort and expands the application of Dirac mode in the conventional silica-based optical fiber devices.

Based on the plasticity theory of upper bound limit analysis, the expression of a potential collapse profile of a tunnel can be obtained from the $$\sigma $$ $$_{n}$$ $$-$$ $$\tau $$ $$_{n}$$ form of the Hoek–Brown criterion. However, because the parameters Aand B in the Hoek–Brown expression are difficult to determine, the bolts parameters cannot be determined easily. Therefore, it is necessary to adopt a parameter transformation method to establish the relation between the parameters in the general form ( $$\sigma $$ $$_{1}$$ $$-$$ $$\sigma $$ $$_{3}$$ form) and the $$\sigma $$ $$_{n}$$ $$-$$ $$\tau $$ $$_{n}$$ form of the Hoek–Brown criterion. The field rock data can be used to determine the critical span of tunnel collapse under different parameters. Then, the impact of the parameters of the rock mass, such as GSI, $$m_{i}$$ , D, $$\sigma $$ $$_{ci}$$ , and $$\gamma $$ are studied. And based on the L and h of the profile (L is the half span of the profile and h is the height), we studied the reasonable bolt parameters. The result shows that if the rock is more intact (GSI is larger), $$m_{i}$$ is smaller, the blasting disturbance is smaller (D is smaller), the compressive strength is larger ( $$\sigma $$ $$_{ci}$$ is larger), and the density of the rock is smaller, the range of the potential collapse profile is smaller. Generally, the support effect is more efficient when the length of the bolts is 2h and the spacing between the bolts is 15–20% of L. This research can provide a reliable reference for the accurate judgment of tunnel stability and effective control of roof settlement.

A new kind of erbium-doped solid-core photonic bandgap fiber (ED-SC-PBGF) for amplification of orbital angular momentum (OAM) modes is proposed and investigated. The configurations of annular erbium-doped profile with special design and multi pump modes are used to amplify the signal modes evenly. Using an optimized ED-SC-PBGF pumped with l = 1 and 2 modes, differential mode gains of 0.9 dB and gain of more than 20 dB can be achieved for l = 1 and 2 OAM signal modes across the full C-band. This OAM-in-fiber amplification techniques would have potential application in ultra-long distance and high capacity OAM optical communication systems and other systems that utilize high power OAM light.

Inbreeding depression confers reduced fitness among the offspring of genetic relatives. As a clonally propagated crop, potato (Solanum tuberosum L.) suffers from severe inbreeding depression; however, the genetic basis of inbreeding depression in potato is largely unknown. To gain insight into inbreeding depression in potato, we evaluated the mutation burden in 151 diploid potatoes and obtained 344,831 predicted deleterious substitutions. The deleterious mutations in potato are enriched in the pericentromeric regions and are line specific. Using three F2 populations, we identified 15 genomic regions with severe segregation distortions due to selection at the gametic and zygotic stages. Most of the deleterious recessive alleles affecting survival and growth vigor were located in regions with high recombination rates. One of these deleterious alleles is derived from a rare mutation that disrupts a gene required for embryo development. This study provides the basis for genome design of potato inbred lines.

A novel and robust sensing platform based on a metal–organic framework (MOF) integrated hydrogel optical fibre is proposed for fluorescence detection for the first time. The core–clad structure of the hydrogel optical fibre with a step index profile can enable efficient excitation light delivery and luminescence emission collection. Meanwhile, immobilization of the luminescent MOFs in the core of the hydrogel fibre prevents the MOFs from directly contacting the harsh environment, while reserving channels for analyte penetration and interaction with the MOFs. In the representative experiment, water and thermo stable EuNDC (H2NDC = 1,4-naphthalenedicarboxylic acid) is synthesized as a fluorescent material for highly selective detection of explosive picric acid (PA). Fluorescence quenching is visible to the naked eye at a PA concentration of as low as 5.7 ppm. The EuNDC integrated hydrogel optical fibre enables the realization of highly selective detection of explosive picric acid (PA) over other nitroaromatic compounds and metal ions, which demonstrates the potential of the hydrogel fibre as a portable, robust sensing platform for highly selective, on-site and real-time quantitative monitoring.

An over-20-octaves-bandwidth ultralow-intensity-noise 1064-nm single-frequency fiber laser (SFFL) is demonstrated based on a comprehensive all-optical technique. With a joint action of booster optical amplifier (BOA) and reflective Yb-doped fiber amplifier (RYDFA), two-fold optical gain saturation effects, respectively occurring in the media of semiconductor and fiber, have been synthetically leveraged. Benefiting from the gain dynamics in complementary time scales, i.e., nanosecond-order carrier lifetime in BOA and millisecond-order upper-level lifetime in RYDFA, the relative intensity noise (RIN) is reduced to −150 dB/Hz from 0.2 kHz to 350 MHz, which exceeds 20-octaves bandwidth. Remarkably, a maximum suppressing ratio of >54 dB is obtained, and the RIN in the range of 0.09–10 GHz reaches −161 dB/Hz which is only 2.3 dB above the shot-noise limit. This broad-bandwidth ultralow-intensity-noise SFFL can serve as an important building block for squeezed light generation, space laser communication, space gravitational wave detection, etc.

In this work, we report on the vector and scalar soliton dynamics that result from inevitable fiber birefringence in an 8-mm Er3+/Yb3+ fiber based Fabry-Férot (FP) laser that has a free spectral range of up to 12.5 GHz. The generation of polarization-evolving vector solitons can largely degrade the performance of application systems, and the underlying mechanisms and manipulation technologies are yet to be explored. To realize the transition from vector to scalar (linearly polarized) state, we here incorporate the polarization selection effect (PSE) in the simulation model and the numerical results verify that only a small amount of PSE is sufficient for manipulating the soliton dynamics. It also reveals that, prominent polarization-dependent intensity discrimination can be acquired via geometry-induced oblique incidence to the Bragg mirror of the semiconductor saturable absorber mirror (SESAM), and we obtain switchable operating states by tilting the SESAM in the experiments. These efforts create a feasible method to manipulate high-repetition-rate pulse and may shed light on understanding the dissipative soliton dynamics in ultrafast fiber FP lasers.

Triple-negative breast cancer (TNBC) exhibits aggressive behavior and high levels of metastasis owing to its complex heterogeneous structure and lack of specific receptors. Here, tumor cell membrane (CM)-coated bismuth/manganese oxide nanoparticles (NPs) with high indocyanine green (ICG) payload up to 50.6 wt% (mBMNI NPs) for targeted TNBC therapy are constructed. The extra-high drug load Bi@Bi2 O3 @MnOx NPs (honey-comb like structure) are formed by Kirkendall effect and electrostatic attraction. After modified with CM, they can home into tumor sites precisely, where they respond to internal overexpressed glutathione (GSH), releasing Mn2+ for chemodynamic therapy (CDT) with GSH depletion, while H2 O2 degrades into O2 enabling relief of tumor hypoxia. In response to external near-infrared irradiation, mBMNI NPs intelligently generate vigorous heat and single oxygen (1 O2 ) for photothermal therapy (PTT) and photodynamic therapy (PDT) owing to high load. Importantly, O2 production and GSH consumption during the internal response reinforce external PDT, while the heat generated through PTT during the external response promotes internal CDT. The honeycomb-like structure with high ICG load and mutual reinforcement between internal and external response results in excellent therapeutic effects against TNBC.

Further development of high-efficiency and low-cost organic fluorescent materials is intrinsically hampered by the energy gap law and spin statistics, especially in the near-infrared (NIR) region. Here we design a novel building block with aggregation-induced emission (AIE) activity for realizing highly efficient luminophores covering the deep-red and NIR region, which originates from an increase in the orbital overlap and electron-withdrawing ability. An organic donor–acceptor molecule (BPMT) with the building block is prepared and can readily form J-type molecular columns with multiple C–H⋯N/O interactions. Notably, such synthesized materials can emit fluorescence centered at 701 nm with extremely high photoluminescence quantum yields (PLQYs) of 48.7%. Experimental and theoretical investigations reveal that the formation of the hybridized local and charge-transfer (HLCT) state and substantial C–H⋯N/O interactions contribute to a fast radiative decay rate and a slow nonradiative decay rate, respectively, resulting in high PLQYs in the solid state covering the NIR range. Remarkably, such BPMT crystals, as a first example, reveal strong-penetrability piezochromism along with a distinct PL change from the deep-red (λmax = 704 nm) to NIR (λmax = 821 nm) region. Moreover, such typical AIE-active luminophores are demonstrated to be a good candidate as a lasing medium. Together with epoxy resin by a self-assembly method, a microlaser is successfully illustrated with a lasing wavelength of 735.2 nm at a threshold of 22.3 kW cm−2. These results provide a promising approach to extend the contents of deep-red/NIR luminophores and open a new avenue to enable applications ranging from chemical sensing to lasing., A HLCT-type luminophore is prepared with bright deep-red fluorescence, showing high-performance piezochromism and lasing.

Fire resistance and seismic performance are the two of the most important considerations for the design of construction steel. The fire resistance of the high-strength construction steel, Q460FRE, which contains low Mo, was investigated by means of creep test under different experiment conditions. Then, the seismic performance of the Q460FRE steel, after being subjected to various fire temperatures, was characterized by internal friction analysis. The Q460FRE steel exhibited excellent fire resistance, and the yield strength at 600 °C was 67.4% of the yield strength at room temperature. The constitutive equation of creep stress and fracture time at 600 °C was established. The bearing tensile stress of the Q460FRE steel should be lower than 337 MPa to ensure at least 1 h to evacuate from the fire. The creep stress and alternating temperature significantly affected the serration behavior of the creep strain. The internal friction analysis indicated that the seismic performance of the Q460FRE steel decreased with the increase in fire temperature, being consistent with the analysis results of the seismic performance characterized by the yield ratio.

Optical fibers have been widely applied to life science, such as laser delivering, fluorescence collection, biosensing, bioimaging, etc. To resolve the challenges of advanced multiphoton biophotonic applications utilizing ultrashort laser pulses, here we report a flexible diameter-oscillating fiber (DOF) with microlens endface fabricated by using Polydimethylsiloxane (PDMS) elastomers. The diameter of the DOF is designed to longitudinally vary for providing accurate dispersion management, which is important for near-infrared multiphoton biophotonics that usually involves ultrashort laser pulses. The variation range and period of the DOF’s diameter can be flexibly adjusted by controlling the parameters during the fabrication, such that dispersion curves with different oscillation landscapes can be obtained. The dispersion oscillating around the zero-dispersion baseline gives rise to a minimized net dispersion as the ultrashort laser pulse passes through the DOF — reducing the temporal broadening effect and resulting in transform-limited pulsewidth. In addition, the endface of the DOF is fabricated with a microlens, which is especially useful for laser scanning/focusing and fluorescence excitation. It is anticipated that this new biocompatible DOF is of great interest for biophotonic applications, particularly multiphoton microscopy deep inside biological tissues.

Overexpression of reactive oxygen species in the substantia nigra pars compacta destroys dopaminergic neurons and accelerates the pathological process of Parkinson's disease (PD). In this study, a new hydrophilic nano-bioconjugate, lactoferrin (Lf)-modified Au-Bi

Silicate-clad heavily

For first-order topological semimetals, non-Hermitian perturbations can drive the Weyl nodes into Weyl exceptional rings having multiple topological structures and no Hermitian counterparts. Recently, it was discovered that higher-order Weyl semimetals, as a novel class of higher-order topological phases, can uniquely exhibit coexisting surface and hinge Fermi arcs. However, non-Hermitian higher-order topological semimetals have not yet been explored. Here, we identify a new type of topological semimetals, i.e, a higher-order topological semimetal with Weyl exceptional rings. In such a semimetal, these rings are characterized by both a spectral winding number and a Chern number. Moreover, the higher-order Weyl-exceptional-ring semimetal supports both surface and hinge Fermi-arc states, which are bounded by the projection of the Weyl exceptional rings onto the surface and hinge, respectively. Noticeably, the dissipative terms can cause the coupling of two exceptional rings with opposite topological charges, so as to induce topological phase transitions. Our studies open new avenues for exploring novel higher-order topological semimetals in non-Hermitian systems., Comment: Published Version

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Supplemental information

Summary Due to the in situ, real-time, and non-destructive properties, mechanoluminescence (ML) crystals have been considered as intelligent stress sensors, which demonstrate potential applications such as in inner crack visualization, light source, and ultrasonic powder recording. Thereinto, it is highly expected that near-infrared (NIR) MLs can realize the visualization of inner biological stress because mechanically induced signals from them can penetrate biological tissues. However, such an energy conversion technique fails to work in biomechanical monitoring due to the limited advances of NIR ML materials. Based on those, some research groups have begun to focus on this field and initially realized this idea in vitro while related advances are still at the early stage. To advance this field, it is highly desirable to review recent advances in NIR ML crystals. In this review, to our knowledge, all the NIR ML crystals have been included in two main groups: oxysulfides and oxides. Besides, the present and emerging trends in investigation of such crystals were discussed. In all, the aim is to advance NIR ML crystals to more practical applications, especially for that of biomechanical visualization in vivo., Graphical Abstract, Medical Imaging; Optical Materials; Biomedical Material

Computer tomography (CT) and magnetic resonance imaging (MRI) are noninvasive cancer imaging methods in clinics. Hence, a material that enables MRI/CT dual-modal imaging-guided therapy is in high demand. Currently, the available materials lack active tumor targeting, deep tumor penetration, and ultralong tumor retention and may lose their imaging elements. To overcome these drawbacks, herein, nanoparticles (NPs) were deveopled by integrating an MRI contrast-enhancing chelated gadolinium (Gd) complex within a doxorubicin (DOX)-loaded protective silica shell as well as a CT imaging/photothermal biocompatible bismuth (Bi) nano-core, which surface-displayed an MCF-7 breast tumor-homing peptide (AREYGTRFSLIGGYR, termed AR); we found that the resultant NPs AR-Bi@SiO(2)-Gd/DOXNPs could home to and penetrate deep into the tumors with the unexpected ultralong retention of at least 14 days (as determined by CT/MRI imaging) and the tumor retention half-life of 104.5 h (as determined by ICP-MS analysis) under the guidance of the AR peptide. These NPs can be further used to image tumors with significantly increased sharp contrasts via both CT and MRI, which are much better than the commercial standard contrast agents; moreover, they significantly inhibit tumor growth via the synergistic action of both Bi-enabled photothermal therapy and DOX-induced chemotherapy. The NPs are cleared by the spleen, liver and kidney and then excreted from the body along with faeces and urine. The precise tumor targeting and ultralong tumor retention of these unique NPs would enable both precise tumor detection for early diagnosis and signal-persistent tumor tracking for monitoring the treatment with only a single injection of these NPs.