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Abstract Ultrafast lasers have become powerful tools in various fields, and increasing their fundamental repetition rates to the gigahertz (GHz) level holds great potential for frontier scientific and industrial applications. Among various schemes, passive mode-locking in ultrashort-cavity fiber laser is promising for generating GHz ultrashort pulses (typically solitons), for its simplicity and robustness. However, its pulse energy is far lower than the critical value of the existing theory, leading to open questions on the mode-locking mechanism of GHz fiber lasers. Here, we study the passive mode-locking in GHz fiber lasers by exploring dynamic gain depletion and recovery (GDR) effect, and establish a theoretical model for comprehensively understanding its low-threshold mode-locking mechanism with multi-GHz fundamental repetition rates. Specifically, the GDR effect yields an effective interaction force and thereby binds multi-GHz solitons to form a counterpart of soliton crystals. It is found that the resulting collective behavior of the solitons effectively reduces the saturation energy of the gain fiber and permits orders of magnitude lower pulse energy for continuous-wave mode-locking (CWML). A new concept of quasi-single soliton defined in a strongly correlated length is also proposed to gain insight into the dynamics of soliton assembling, which enables the crossover from the present mode-locking theory to the existing one. Specifically, two distinguishing dynamics of Q-switched mode-locking that respectively exhibit rectangular- and Gaussian-shape envelopes are theoretically indicated and experimentally verified in the mode-locked GHz fiber laser through the measurements using both the standard real-time oscilloscope and emerging time-lens magnification. Based on the proposed criterion of CWML, we finally implement a GDR-mediated mode-locked fiber laser with an unprecedentedly high fundamental repetition rate of up to 21 GHz and a signal-to-noise ratio of 85.9 dB.

Given the worldwide epidemic of overweight and obesity among children, evidence-based dietary recommendations are fundamentally important for obesity prevention. Although the significance of the human gut microbiome in shaping the physiological effects of diet and obesity has been widely recognized, nutritional therapeutics for the mitigation of pediatric obesity globally are only just starting to leverage advancements in the nutritional microbiology field. In this review, we extracted data from PubMed, EMBASE, Scopus, Web of Science, Google Scholar, CNKI, Cochrane Library and Wiley online library that focuses on the characterization of gut microbiota (including bacteria, fungi, viruses, and archaea) in children with obesity. We further review host-microbe interactions as mechanisms mediating the physiological effects of dietary fibers and how fibers alter the gut microbiota in children with obesity. Contemporary nutritional recommendations for the prevention of pediatric obesity are also discussed from a gut microbiological perspective. Finally, we propose an experimental framework for integrating gut microbiota into nutritional interventions for children with obesity and provide recommendations for the design of future studies on precision nutrition for pediatric obesity.

Allium fistulosum is an important plant germplasm resource, rich in nutrients and possessing unique medicinal value. However, due to its small floral organs, low seed setting rate of a single flower, high cost of artificial emasculation, and artificial pollination, the use of male sterile lines to prepare Allium hybrids has become a common choice. In this study, A. fistulosum var. viviparum Makino and A. galanthum were used as materials to study the regulation mechanism of anther development, aiming to provide a reference for male sterility. Through transcriptome differential gene screening and genome-wide bioinformatics analysis, 34 SKP1 (S-phase kinase-associated protein 1) genes (AfSKP1-1 to AfSKP1-34) were identified in the whole genome of A. fistulosum. The AfSKP1 genes are unevenly distributed on eight chromosomes. Furthermore, two pairs of collinear relationships are evident among family members, and fragment replication events between AfSKP1 genes have been identified. The phylogenetic tree analysis demonstrated that the AfSKP1, AtSKP1, OsSKP1, and SlSKP1 genes were clustered into six groups, exhibiting a gene structure analogous to that observed in members of an evolutionary classification. A combination of gene structure and phylogenetic analysis revealed the presence of cis-acting elements associated with growth, hormone regulation, and stress response within the AfSKP1 genes. Furthermore, expression analysis demonstrated that the AfSKP1 genes exhibited differential expression patterns across various tissues of A. fistulosum. The tissue-specific expression of the AfSKP1 gene was verified by Real-Time PCR. A comparison of the two materials revealed significant differences in the expression of the AfSKP1-8 gene in floral buds, the AfSKP1-11 gene in inflorescence meristems, and the AfSKP1-14 gene in inflorescence meristems, scapes, and floral buds. The results indicated that the three genes may be involved in anther development, thereby providing a theoretical basis for further study of floral organ development and pollen development in AfSKP1 family members.

Herein, the lasing action of fabricated bulged CH3NH3PbBr3 microwires is demonstrated with features of a low threshold, narrow linewidth, single‐mode operation, and high intensity. Benefiting from the bulged end facets, the CH3NH3PbBr3 microwires are feasible for constructing a high‐brightness, whispering‐gallery‐mode(WGM)‐type, and single‐mode laser while suppressing Fabry–Pérot‐type multi‐mode lasing. Numerical simulation unveils that the bulged end facets result in the significantly reduced reflectivity of fundamental waveguided modes. The obtained microlasers require neither complex structures (such as distributed Bragg reflector) nor careful pumping adjustment, suggesting the practical feasibility of a higher single‐mode lasing intensity than conventional WGM perovskite microlasers. The results provide new routes to realize high‐performance perovskite microlasers and their potential application in sensing refractive index.

The pursuit of compact and integrated devices has stimulated a growing demand for multifunctional sensors with rapid and accurate responses to various physical parameters, either separately or simultaneously. Fluorescent fiber sensors have the advantages of robust stability, light weight, and compact geometry, enabling real-time and noninvasive signal detection by monitoring the fluorescence parameters. Despite substantial progress in fluorescence sensors, achieving multifunctional sensing in a single optical fiber remains challenging. To solve this problem, in this study, we present a bottom-up strategy to design and fabricate thermally drawn multifunctional fiber sensors by incorporating functional nanocrystals with temperature and pressure fluorescence responses into a transparent glass matrix. To generate the desired nanocrystal-in-glass composite (NGC) fiber, the fluorescent activators, incorporated nanocrystals, glassy core materials, and cladding matrix are rationally designed. Utilizing the fluorescence intensity ratio technique, a self-calibrated fiber sensor is demonstrated, with a bi-functional response to temperature and pressure. For temperature sensing, the NGC fiber exhibits temperature-dependent near-infrared emission at temperatures up to 573 K with a maximum absolute sensitivity of 0.019 K−1. A pressure-dependent upconversion emission is also realized in the visible spectral region, with a linear slope of -0.065. The successful demonstration of multifunctional NGC fiber sensors provides an efficient pathway for new paradigms of multifunctional sensors as well as a versatile strategy for future hybrid fibers with novel combinations of magnetic, optical, and mechanical properties.

Mechanoluminescent (ML) materials, which have the ability to convert mechanical energy to optical energy, have found huge promising applications such as in stress imaging and anti-counterfeiting. However, the main reported ML phosphors are based on trap-related ones, thus hindering the practical applications due to the requirement of complex light pre-irradiation process. Here, a self-recoverable near infrared (NIR) ML material of LaAl1-xO3: xCr3+ (x=0.2 ​%, 0.4 ​%, 0.6 ​%, 0.8 ​%, 1.0 ​%, and 1.2 ​%) has been developed. Based on the preheating method and corresponding ML performance analysis, the influences of residual carriers are eliminated and the detailed dynamic luminescence process analysis is realized. Systematic experiments are conducted to reveal the origin of the ML emissions, demonstrating that ML is dictated more by the non-centrosymmetric piezoelectric crystal characteristic. In general, this work has provided significant references for exploring more efficient NIR ML materials, which may provide potential applications in anti-counterfeiting and bio-stress sensing.

Abstract Reprogrammable soft matter brings flexibility to soft robots so that they can display various motions, which is flourishing in soft robotics. However, the reprogramming of photoresponsive materials used in soft robots is time-consuming using existing methods. In this study, we promote a strategy for rapid reprogramming via switchable photothermal conversion efficiency (PCE). The liquid crystalline elastomers doped with semiconductor bismuth compounds (Bi-LCE) used in this work exhibited large photothermal actuation with over 35% shrinkage in 5 s at high PCE state, which demonstrated little deformation at low PCE state. Furthermore, the material was capable of being reprogrammed up to 10 times, with only 20 min required for one PCE reversible switch. Based on this switchable PCE effect, the same Bi-LCE film displayed various shape changes through different programmable pattern. Additionally, a reprogrammable hollow tube made of PCE reprogrammable materials could tune the diameter, cross-section configuration, and surface morphology, which was crucial for microfluidics field. Reprogrammable materials provide endless possibilities for reusability and sustainability in robotics.

In this study, a kilowatt-level high-efficiency narrow-linewidth all-fiber Tm3+-doped continuous-wave laser operating at 1.95 μm is demonstrated. Benefitting from an advanced boost design of a two-stage main amplifier, it not only effectively manages heat dissipation resulting from the high pump-induced quantum defect but also realizes the controlled extraction of optical gain and improves the optical conversion efficiency. Finally, this laser system has realized an output power of 1018 W, a linewidth of 3.8 GHz, and a slope efficiency of 60.0% simultaneously. Moreover, a high optical signal-to-noise ratio of over 45 dB and excellent beam quality of M2 factors 1.19 are obtained. To the best of our knowledge, this represents the narrowest linewidth and highest slope efficiency achieved in a kilowatt-level Tm³⁺-doped fiber laser. Such a high-performance laser is ideally suited for mid-infrared generation and remote sensing applications.

Dissipative soliton molecules (DSMs) are of great interest for studying the complexity of nonlinear optical problems as they can map with the matter molecules for making interdisciplinary analogies. In contrast to strongly bound DSMs that have a short time separation between the bound solitons, the complex dynamics and underlying binding mechanism of loosely bound soliton molecules (LBSMs) with orders of magnitude longer time separation remain open questions. To this end, here, we explore real-time spectroscopy using a dispersive temporal interferometer (DTI) to visualize the dynamics of LBSMs in a mode-locked fiber laser and unveil their underlying phase-evolving mechanism. The DTI enables fringe-resolved spectroscopy in real time of the LBSM’s evolution by creating duplicates of the LBSM that results in a much closer time separation between the individual solitons of the LBSM. The real-time evolution of the LBSM’s phase exhibits a diverging sliding landscape, which is theoretically and experimentally proved to be closely associated with gain dynamics. Based on the understanding of its phase dynamics, we finally demonstrate programmable phase-encoding modulation of the LBSM through gain control. These efforts not only shed light on understanding the mechanism of long-range interactions in LBSMs but also provide an alternative approach for all-optical information processing.

Advances in stretchable and flexible sensors are meeting the demands of an expanding range of applications, such as wearable healthcare, in vivo monitoring, and soft interactive robots. Unlike conventional rigid sensors, soft and elastic material-based flexible sensors are more adaptable to applied objects which involve dynamic and irregular surfaces. Flexible optical fiber sensors offer superior advantages over conventional flexible electronic sensors, including high sensitivity, rapid response time, high biocompatibility, immunity to electromagnetic interference, and enhanced safety. These desirable features have propelled them to become a prominent category, witnessing substantial advancements in recent years. This technology has successfully facilitated a diverse range of applications, such as human health monitoring, biological measurements, and human-machine interfaces. In this review, we provide a concise overview of the latest developments in flexible optical fiber sensing, focusing on key aspects, including preparation materials, methodologies, and applications. Furthermore, we provide valuable insights into the potential challenges and opportunities that lie ahead in this field of sensing technology.

Abstract Observing the dynamics of 3D soliton molecules can hold great opportunities for unveiling the mechanism of molecular complexity and other nonlinear problems. In spite of this fantastic potential, real-time visualization of their dynamics occurring on femtosecond-to-picosecond time scales is still challenging, particularly when high-spatiotemporal-resolution and long-term observation are required. In this work, we observe the real-time speckle-resolved spectral-temporal dynamics of 3D soliton molecules for a long time interval using multispeckle spectral-temporal measurement technology. Diverse real-time dynamics of 3D soliton molecules are captured for the first time, including the speckle-resolved birth, spatiotemporal interaction, and internal vibration of 3D soliton molecules. Further studies show that nonlinear spatiotemporal coupling associated with a large average-chirp gradient over the speckled mode profile plays a significant role in these dynamics. These efforts may shed new light on decomposing the complexity of 3D soliton molecules, and create an analogy between 3D soliton molecules and chemical molecules.

Pectin is a structural polysaccharide and a major component of plant cell walls. Pectate lyases are a class of enzymes that degrade demethylated pectin by cleaving the α-1,4-glycosidic bond, and they play an important role in plant growth and development. Currently, little is known about the PL gene family members and their involvement in salt stress in potato. In this study, we utilized bioinformatics to identify members of the potato pectate lyase gene family and analyzed their gene and amino acid sequence characteristics. The results showed that a total of 27 members of the pectate lyase gene family were identified in potato. Phylogenetic tree analysis revealed that these genes were divided into eight groups. Analysis of their promoters indicated that several members’ promoter regions contained a significant number of hormone and stress response elements. Further, we found that several members responded positively to salt treatment under single salt and mixed salt stress. Since StPL18 exhibited a consistent expression pattern under both single and mixed salt stress conditions, its subcellular localization was determined. The results indicated that StPL18 is localized in the endoplasmic reticulum membrane. The results will establish a foundation for analyzing the functions of potato pectate lyase family members and their expression under salt stress.

Optical temperature sensors, which can accurately detect temperature in biological systems, are crucial to the development of healthcare monitoring. To challenge the state-of-art technology, it is necessary to design single luminescence center doped materials with multi-wavelength emission for optical temperature sensors with more modes and higher resolution. Here, an Er3+ single-doped KYF4 nanocrystals glass ceramic with an obvious thermochromic phenomenon is reported for the first time, which shows a different temperature-dependent green, red, and near-infrared luminescence behavior based on thermal disturbance model. In addition, Er3+ single-doped GC fiber was drawn and fabricated into multi-mode optical fiber temperature sensor, which has superior measured temperature resolution (＜0.5 ​°C), excellent detection limit (0.077 ​°C), and high correlation coefficient (R2) of 0.99997. More importantly, this sensor can monitor temperature in different scenarios with great environmental interference resistance and repeatability. These results indicate that our sensor shows great promise as a technology for environmental and healthcare monitoring, and it provides a route for the design of optical fiber temperature sensors with multi-mode and high resolution.

The ability to locate and quantify large strains will significantly improve the real‐world application scenario of flexible and stretchable strain sensors. However, current methods for implementing stretchable distributed strain sensing still face challenges such as complicated demodulation, multisensor crosstalk, and high power consumption. Herein, a self‐powered and stretchable optical fiber strain sensor is reported with distributed sensing capability based on mechanoluminescent optical fiber, where mechanoluminescent phosphors with different emission color light are discretely integrated onto the outer cladding of the elastomer optical fiber. Based on the wavelength coding technique and time‐domain filtering comparison method, the capability of strain magnitude quantification (10–60%) and strain location identification together in a single stretchable optical fiber is successfully realized, even at multiple positions simultaneously in the strain‐applied situation. Moreover, this stretchable optical fiber strain sensor shows insensitivity to bending, compression, and temperature disturbances and outstanding durability (>8000 cycles). Due to the excellent light confinement of the elastomer optical fiber, demonstrations such as bright‐field measurement, saline water operation, and wearable glove application exhibit its potential as a promising technology for future self‐powered distributed optical sensing systems.

Flexible strain sensors are essential components of wearable smart devices that perceive and respond to strain stimulations. However, the sensitivity and response time of most sensors require further improvement to detect subtle strains related to human bodies. Herein, an ultrasensitive flexible optical sensor with fast response time has been built based on a microfiber coupler encapsulated in polydimethylsiloxane. Benefiting from dramatic change of coupling ratio of the microfiber coupler under weak strain, this flexible strain sensor exhibits ultrahigh strain sensitivity (gauge factor, GF = 900), low detection limit (0.001%), ultrafast response time (10 000 cycles). Real‐time capturing and recognizing of respiration, broadband sound signals, and pulse waves at different sites of human body have been demonstrated based on this highly sensitive microfiber coupler sensor. Moreover, simultaneous detection of the wrist pulse and human voice has been achieved based on the frequency division multiplexing technology. This flexible photonics strain sensor could serve as the prototype of ultrasensitive flexible optical sensors with fast response time for the development of high performance and wearable healthcare devices.

The species degeneration caused by traditional potato cultivation methods is becoming increasingly evident, and it is particularly important to study new potato cultivation methods. Sprout planting technology has the advantages of large reproductive capacity, fast growth speed, and simplified maintenance of cultivated crops. In this study, four disease-free potato varieties (‘Fujin’, ‘Youjin’, ‘Zhongshu 4’, and ‘Feiwuruita’) were treated with different parts (top bud, middle bud, and tail bud) and different bud lengths (10 cm, 15 cm, and 20 cm), and then potato sprout planting was carried out. A nutrient pot experiment was performed following a randomized complete block design (RCBD) with various replicates and a natural control (CK) treatment. By comprehensively measuring the emergence, chlorophyll content, net photosynthetic rate, dry matter distribution during the bulking period of blocks, and effect of growth and quality with bud direct seeding under both treatments, it was found that potato block top bud direct seeding cultivation is significantly superior to other parts. In terms of early maturity and yield statistics, the advantage of top bud cultivation in ‘zhongshu 4’ is most obvious; it reaches maturity an average of 14 days earlier, and the yield can be increased by 38.05%. Therefore, top bud direct seeding is more suitable for potato sprout planting technology. On this basis, the 20 cm and 15 cm bud length treatments of top buds were used for direct cultivation, and all the above indicators performed well. Among them, in the zhongshu 4 variety, the yields of 15 cm and 20 cm bud length treatments increased by 41.78% and 38.05%, the growth rates of commercial potatoes increased by 6% and 6.9%, respectively, and the effects were the most obvious. In conclusion, the deep research and application of potato sprouting technology has high utilization value for improving potato yield and quality and has guiding significance for greenhouse potato cultivation in early spring.

Abstract Sepsis, caused by uncontrollable infection and inflammatory response, leads to more than 30 million infected patients and results in high morbidity worldwide every year. Currently, no efficient approaches have been developed for sepsis therapy due to antimicrobial resistance and inflammatory storm. Here, we report macrophages loaded with aggregated carbon dots (ACDs) in the lysosome, termed MCDs, to treat sepsis in immunosuppressive mice. The ACDs are constructed by negative CDs and amine‐abundant polyethyleneimine (PEI), enabling them to bear the strong antibacterial ability and enhanced photoluminescent efficacy. The ACDs are specifically located in the macrophage lysosomes, efficiently enhancing the multidrug‐resistant bacteria‐killing ability of MCDs. More importantly, the MCDs possess superior anti‐inflammatory effects such as reducing the number of pro‐inflammatory (M1) and stimulating anti‐inflammatory (M2) macrophages. These effects upregulate the inflammatory cytokines (TNF‐α, IL‐1β, IL‐4, and IL‐10), ultimately resulting in increased sepsis survival. Our work provides an intelligent approach to overcoming multidrug‐resistant bacteria‐induced infection from sepsis patients and paves a new avenue on employing nanoparticle‐loaded cells for combating inflammation‐related infection.

In this work, we present a high-power, high-repetition-rate, all-fiber femtosecond laser system operating at 1.5 $\unicode{x3bc}$ m. This all-fiber laser system can deliver femtosecond pulses at a fundamental repetition rate of 10.6 GHz with an average output power of 106.4 W – the highest average power reported so far from an all-fiber femtosecond laser at 1.5 $\unicode{x3bc}$ m, to the best of our knowledge. By utilizing the soliton-effect-based pulse compression effect with optimized pre-chirping dispersion, the amplified pulses are compressed to 239 fs in an all-fiber configuration. Empowered by such a high-power ultrafast fiber laser system, we further explore the nonlinear interaction among transverse modes LP01, LP11 and LP21 that are expected to potentially exist in fiber laser systems using large-mode-area fibers. The intermodal modulational instability is theoretically investigated and subsequently identified in our experiments. Such a high-power all-fiber ultrafast laser without bulky free-space optics is anticipated to be a promising laser source for applications that specifically require compact and robust operation.

Technology spillover is crucial to achieving economic development while also reducing CO2 emissions. The success of diffusion depends critically upon advanced intellectual property rights (IPR) protection and the level of infrastructure. Several studies have discussed the relationship between technology spillover and CO2 emissions. However, very few studies have addressed the impacts of socio-economic factors, particularly IPR protection and transportation infrastructure (TI) (the two concepts that are directly related to technology spillover), on this relationship. Therefore, this study used an extended Environmental Kuznets Curve (EKC) model to explore the relationship between technology spillover and CO2 emissions in China from 1997 to 2018. The study accounted for two threshold variables (IPR protection and TI) in a threshold model to explore the nonlinear effect of technology spillover on CO2 emissions. The findings revealed that: (1) when the IPR protection value was below 8.169, different forms of technology spillover had an optimal effect on CO2 emission reduction; (2) the scale of TI construction should be moderate and below the threshold value; otherwise, greater environmental pressure would occur; and (3) threshold points varied geographically. The results indicated that the level of IPR protection and TI should be adapted to the regional development characteristics to promote economic development and minimize environmental impacts.

The improvement of transportation green total factor productivity (GTFP) is crucial to the high-quality development of China’s economy under the new normal. Through dynamic and cross-regional comparison of transportation TFP and transportation GTFP, the driving force of transportation GTFP growth was analyzed. An augmented production function model and the geographically weighted regression (GWR) model were combined to analyze the spatial impact of technological progress on transportation GTFP The results are as follows: the effect of R&D investment on transportation GTFP first decreases and then increases. The impact factor of interprovincial technology spillover (DS) on transportation GTFP was always negative during the study period. The influence of foreign direct investment on transportation GTFP depends on the “pollution haven” and “pollution halo” effects. We highlighted the need for regional coordinated development and encouragement of green technology spillover. We should also promote the GTFP growth with regional differentiation.

Abstract Triple-negative breast cancer (TNBC) is one of the most daunting diseases, low toxicity and efficient approaches are in urgent demand. Herein, we developed degradable mesoporous manganese carbonate nanocubes (MnCO3 NCs), incorporated with survivin shRNA-expressing plasmid DNA (iSur-pDNA) and riboflavin (Rf), namely MRp NCs, for synergistic TNBC therapy. The MnCO3, itself, could generate O2 and CO2 under H2O2 and thus relieve the hypoxia and acidic tumor microenvironment (TME). Furthermore, the MnCO3 NCs exhibited high Rf loading capacity and iSur-pDNA delivery ability after polyethyleneimine modification. Specifically, MRp NCs decompose in TME, meanwhile they deprived the endogenous expression of survivin gene and significantly amplified the generation of reactive oxygen species after exposure to LED light, resulting in serious tumor destruction. The multifunctional MRp NCs with LED light-driven characters are able to provide a high efficiency, low toxicity and promising strategy for TNBC therapy.

A 1.5 μm ultralow‐noise single‐frequency fiber laser (SFFL) is realized based on a delay fiber phase‐locked method and the nonlinear amplification effect of a semiconductor optical amplifier (SOA). Via feedback locking of the phase jitter signal, the phase noise achieves the minimum value of −160 dB rad Hz−1/2 m−1 with a maximum reduction of 50 dB. Meanwhile, SOA reduces the intensity noise by a maximum of 65 dB, making it near the shot‐noise limit for frequencies above 40 kHz. To demonstrate this state‐of‐art SFFL with ultralow‐noise property, a high‐resolution fiber‐optic dynamic strain sensing based on a fiber‐based Michelson interferometer (FMI) is performed. As a result, the strain resolution reaches 26 fε Hz−1/2 in the 30–200 Hz band, which is improved by almost three orders of magnitude than that realized by a free‐running SFFL. To the best of the knowledge, this is the first time to achieve such a high‐resolution fiber‐optic dynamic strain sensor in the low‐frequency range utilizing the FMI system. This high‐resolution fiber‐optic strain sensing has promising applications in geophysics and biophotonics. Moreover, this ultralow‐noise SFFL is competitive for sophisticated applications, such as precise absolute distance measurement, quantum key distribution, and generating squeezed light.

Mixing the crude oil in a floating-roof tank with a rotary jet mixer during heating can increase the heat exchange so that the crude oil can be heated evenly. In order to study the effect of the rotation speed of a rotary jet mixer on the heating efficiency of crude oil, a 3D model of floating-roof tank with a capacity of 10 000 m3 was established through analyzing the heat exchange process of floating-roof tanks during heating to simulate the heating process of crude oil at different rotation speeds of the rotary jet mixer. The results indicate that, the rate of temperature rise in crude oil in the floating-roof tank mixed by the rotary jet mixer is significantly higher that without mixing, and the rate of temperature rise in crude oil increases as the rotation speed of the rotary jet mixer increases. However, there is critical point for the rotation speed. The rate of temperature rise of crude oil decreases when the rotation speed is too high. Conclusively, mixing can greatly improve the uneven temperature distribution of crude oil during heating, and the study results can provide a theoretical basis for enhancing the heating efficiency of a floating-rood tank in actual production.

Background 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. Methods 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 T1, T2, and T3 treatments, and terminal buds, middle buds, and tail buds were used as the T4, T5, and T6 treatments. A nutrient pot experiment was performed following a randomized complete block design (RCBD) with three replicates and a natural control (CK) treatment. Cultivation was performed with the common horticultural practices of weeding and hoeing applied as needed. The photosynthetic indices, physiological indices, growth indices and quality of potato seedlings and quality of potato buds were measured at two-week intervals, and yield indices were measured when the final crop was harvested 14 weeks after planting. Results and Conclusions Cultivation 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.

Root-knot nematode (RKN) infections are among the most serious soil-borne diseases in the world, and tomato is a common host of RKNs. WRKY transcription factors are involved in complex, diverse biological processes in plants. In a previous study, a resistant variety, LA3858 (Mi-3/Mi-3), was treated at different soil temperatures before RNA-seq, and six differentially expressed genes (DEGs) encoding WRKY proteins were screened. In this study, cloning and sequencing were used to identify six target DEGs encoding SlWRKY1, SlWRKY13, SlWRKY30, SlWRKY41, SlWRKY46, and SlWRKY80. Conserved domain identification and phylogenetic tree analysis showed that SlWRKY1, SlWRKY13, and SlWRKY46 have similar functions and are mainly involved in plant growth and development and abiotic stress responses. SlWRKY30 and SlWRKY41 share high homology, while AtWRKY46 and AtWRKY70, which are highly homologous to SlWRKY80, play an important role in the disease resistance of A. thaliana. Considering these findings combined with the high level of SlWRKY80 expression observed in the roots and leaves of the resistant variety Motelle (Mi-1/Mi-1) and the continuous upregulation of SlWRKY80 expression in the roots after inoculation of Motelle with M. incognita, it is speculated that SlWRKY80 plays an important role in the Mi-1-mediated disease resistance pathway. Further study revealed that SlWRKY80 is a typical nuclear-localized protein, and a virus-induced gene silencing (VIGS) assay verified that SlWRKY80 is involved in tomato resistance to RKNs as a positive regulator. SA and JA signals play an important role in Mi-1-mediated resistance to RKNs. SlWRKY80 was able to respond rapidly to treatment with both plant hormones, which indicated that SlWRKY80 might be involved in disease resistance regulation through various immune pathways.

Yellow lasers are of great interest in biology, medicine and display technology. However, nonlinear emission of near-infrared lasers at yellow still presents particularly complex optical alignment to date. Here, to the best of our knowledge, we demonstrate the fabrication of a NaLa(WO4)2: Dy3+ glass-ceramic fiber (GCF) for the first time. More importantly, the emission band of the GCF, which is around 575 nm, has a wide full-width half maximum (FWHM) of 18~22 nm, which is remarkably larger than that of the Dy3+-doped YAG crystal (

Observing 3D dissipative solitons is very challenging since their formation is stochastically and not repeatable. Here, the authors report the real-time multispeckle spectral-temporal observation of dissipative solitons in an optical fiber and analyze their long term evolution.

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.

Abstract 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.

High-performance thermoelectric fibers with n-type bismuth telluride (Bi2Te3) core were prepared by thermal drawing. The nanosheet microstructures of the Bi2Te3 core were tailored by the whole annealing and Bridgman annealing processes, respectively. The influence of the annealing processes on the microstructure and thermoelectric performance was investigated. As a result of the enhanced crystalline orientation of Bi2Te3 core caused by the above two kinds of annealing processes, both the electrical conductivity and thermal conductivity could be improved. Hence, the thermoelectric performance was enhanced, that is, the optimized dimensionless figure of merit (ZT) after the Bridgman annealing processes increased from 0.48 to about 1 at room temperature.

Strain sensors that can work sustainably and continuously without any external power supply are highly desirable for future wearable and implantable devices. Herein, a self‐powered stretchable strain sensor based on the integration of mechanoluminescent phosphors with an elastomer optical fiber is proposed and developed. This mechanoluminescent optical fiber is capable of emitting light just driven by external strain, without the need of an external light source or electric power. The strain‐induced emitted light can be collected and guided along the mechanoluminescent optical fiber. The sensor exhibits linear strain response up to 50% and high‐accuracy strain measurement (±1%). Moreover, this optical fiber strain sensor displays consistent signals over 10 000 stretch–release motion cycles, which demonstrates the good durability of the sensor. Due to the excellent light confinement of the elastomer optical fiber, this strain sensor is demonstrated in both bright‐ and dark‐field measurements, wearable gloves, and an implantable sensing device, thereby demonstrating potential as a promising technology for future self‐powered optical sensor systems.

Mechanoluminescent (ML) materials, which have the ability to convert mechanical energy to optical energy, have found huge promising applications such as in stress imaging and anti-counterfeiting. However, the main reported ML phosphors are based on trap-related ones, thus hindering the practical applications due to the requirement of complex light pre-irradiation process. Here, a self-recoverable near infrared (NIR) ML material of LaAl1-xO3: xCr3+ (x = 0.2 %, 0.4 %, 0.6 %, 0.8 %, 1.0 %, and 1.2 %) has been developed. Based on the preheating method and corresponding ML performance analysis, the influences of residual carriers are eliminated and the detailed dynamic luminescence process analysis is realized. Systematic experiments are conducted to reveal the origin of the ML emissions, demonstrating that ML is dictated more by the non-centrosymmetric piezoelectric crystal characteristic. In general, this work has provided significant references for exploring more efficient NIR ML materials, which may provide potential applications in anti-counterfeiting and bio-stress sensing. [ABSTRACT FROM AUTHOR]

The majority of crops we eat today are derived from the domestication of their wild progenitors. Crop domestication satisfies the human need for food and nutrition. Characterization of the history and genetic basis of crop domestication is essential for us to conduct modern breeding practices. Genomics provide unprecedented opportunities for us to study domestication. In this review, the typical domestication syndromes of horticultural crops will be introduced. Using the tomato as a typical example, we will discuss how genetic and genomic data were used to decipher the origins, progenitors, and domestication processes of this crop. In the domestication exploration of the genetic basis especially, genome-scaled diversity scanning approaches have gained great popularity. Combining these approaches with QTL (Quantitative trait locus)-mapping, GWAS (Genome wide association study), metabolomics and homology-based searches as well as pan-genomics have demonstrated tremendous advantages and significantly contribute to our understanding of domestication. Genomics studies will accelerate domestication research and further breeding of crops. Keywords: domestication syndrome, crop origin, genomic scanning, domestication genes, genetic analysis

Summary: Parkinson’s disease (PD) is a complex neurodegenerative disease affected by diverse factors, and lipid droplets (LDs) are increasingly recognized as major players in PD because of their relevance to neuron activity. However, long-term dynamic changes of LDs and their relative activity remain unclear. Here, an aggregation-induced emission (AIE) probe named 2-DPAN was prepared and employed to visualize dynamic processes of LDs in a 6-hydroxydopamine model of PD for the first time, and LDs' accumulation-peak/plateau-decrease were confirmed. We further found a close relationship between LDs and variation in mitochondrial activity. Strikingly, the progression of cell death was accelerated by lipase, whereas pre-stimulation of LDs by unsaturated fatty acid-oleic acid decreased the death process by inhibiting excessive reactive oxygen species (ROS) and fatty acid production, thereby protecting mitochondria. The utilization of 2-DPAN demonstrates the importance of LDs in neuronal homeostasis, and effective tuning of LDs may prevent or inhibit PD progression. : Disease; Chemical Synthesis; Materials Design Subject Areas: Disease, Chemical Synthesis, Materials Design

In our work, based on chemical vapor deposition method and a newly designed glass-material-glass sandwich structure, MoS2 saturable absorber (SA) with a damage threshold of higher than 0.26 J/cm2 was fabricated and employed for demonstrating high-power, large-energy rectangular mode-locked Er-doped laser operation. Stable mode-locked operation with maximum output power of 122.77 mW and largest pulse energy of 130.49 nJ were successively achieved along with power scaling process. In comparison with previous works, our results show remarkable breakthroughs both in the aspects of average output power and pulse energy. Our experimental design and results will open a new avenue for generating high-power, large-energy mode-locked fiber lasers based on two-dimensional materials as SAs.

Based on hybrid wavelength pumping and tapered Yb-doped fibers (T-YDFs), a 650 W all-fiber single-frequency polarization-maintaining fiber amplifier was demonstrated experimentally at 1030 nm. Different pump power ratios in the T-YDF-based power-amplifier stage were proposed to investigate their influence on the transverse mode instability (TMI) effect. The highest TMI threshold was obtained when the pump power ratio of 940 nm to 976 nm was 1:4.4. A measured M2 factor of 1.7 and a polarization extinction ratio of 14 dB at the maximum output power were obtained. To the best of our knowledge, these results exhibit the highest output power of any all-fiber single-frequency polarization-maintaining fiber amplifiers created up to now.

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.

A 1560 nm high-power linearly-polarized all-fiber single-frequency narrow-linewidth laser with near diffraction-limited beam quality is demonstrated. The Yb–Er energy transfer efficiency and the ability of the signal laser to capture pump light have been improved by specifically choosing the pumping wavelength and the input signal power in the final power amplifier stage of this laser system. Under the off-peak absorption pumping wavelength of 940 nm, along with the maximum input signal power of 6 W, a maximum output power of 102 W with a slope efficiency of 40.5% is acquired. At the highest output power status, a polarization extinction ratio (PER) of 15.5 dB, a linewidth of 3.05 kHz, and a beam quality of Mx2 = 1.14, My2 = 1.06 are obtained, respectively. This advanced single-frequency fiber laser has great potential for the long-range coherent Doppler lidar and the next generation of gravitational wave detection.

Hybrid glass optical fibers incorporated with optoelectronic materials and functionalities are highly anticipated for potential applications in optical communication, remote sensing, biomedicine, and nonlinear optics. However, the design and construction of hybrid glass fibers present significant challenges due to restrictions on the composition of fiber fabricated using conventional chemical vapor deposition (CVD) methods and the difficulty in maintaining the optoelectronic performance stably of fiber prepared by common rod-in-tube fiber-drawing technique. In this review, a versatile fiber-drawing approach which is called “melt-in-tube” (MIT) or “molten core” is presented to produce hybrid glass optical fibers. During the fiber-drawing process, the core is melted whereas the cladding is only just softened. The recent advances of the hybrid glass fibers including glass core-glass cladding fiber, crystal core-glass cladding fiber, and semiconductor core-glass cladding fiber are reported. In addition, the extensive applications of the hybrid glass fibers in the fields of fiber laser, fiber sensing, frequency conversion, photodetection and thermoelectric conversion are also discussed. These breakthroughs and advances in novel fiber materials and applications offer new opportunities for the research and development of optoelectronic devices.

In this paper, a polarization-maintaining quad-wavelength (QW) single-frequency fiber laser (SFFL) at the C-band with the novel and compact structure is demonstrated. Applying the rate equations and multiple coupled nonlinear Schrödinger equations, the theoretical model of QW fiber lasers is established, and then the optical spectra, temporal evolution, and stability of the QW fiber laser are analyzed numerically. Based on the theoretical analysis, a QW-SFFL having an ultrashort linear distributed Bragg reflector cavity is proposed. Utilizing a wideband fiber Bragg grating coupled with a dual-channel polarization maintaining fiber Bragg grating as the wavelength selection and a 15-mm-long Er3+/Yb3+ co-doped phosphate fiber as the gain medium has realized a robust QW laser with the wavelength spacing of 0.4 nm. All the wavelengths maintain the single-frequency operation independently with the linewidths of 20 kHz. This type of compact SFFLs with quadruple wavelengths is widely adapted to lidar systems and fiber sensing.

Quantum defect originating from the stimulated Raman scattering (SRS) effect is a heat source that induces refractive index grating and, thus, significantly decreases the threshold of transverse mode instability (TMI), which is the main limiting factor for the power scaling of high-power fiber lasers. A semi-analytical model that takes the TMI and SRS effects into account was developed, and the impact of the Raman content variation due to changes in the injected seed and fiber length on the TMI threshold was investigated. Experimental demonstrations of the impact of the SRS effect on the TMI threshold are presented. We proved that TMI affects the beam quality of the signal light rather than the Raman light. Taking these facts into account, the suppression of SRS could be an effective way to counter the TMI of fiber lasers.