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Thermal management of nanoscale quantum dots (QDs) in light-emitting devices is a long-lasting challenge. The existing heat transfer reinforcement solutions for QDs-polymer composite mainly rely on thermal-conductive fillers. However, this strategy failed to deliver the QDs’ heat generation across a long distance, and the accumulated heat still causes considerable temperature rise of QDs-polymer composite, which eventually menaces the performance and reliability of light-emitting devices. Inspired by the radially aligned fruit fibers in oranges, we proposed to eliminate this heat dissipation challenge by establishing long-range ordered heat transfer pathways within the QDs-polymer composite. Ultrahigh molecular weight polyethylene fibers (UPEF) were radially aligned throughout the polymer matrix, thus facilitating massive efficient heat dissipation of the QDs. Under a UPEF filling fraction of 24.46 vol%, the in-plane thermal conductivity of QDs-radially aligned UPEF composite (QDs-RAPE) could reach 10.45 W m−1 K−1, which is the highest value of QDs-polymer composite reported so far. As a proof of concept, the QDs’ working temperature can be reduced by 342.5 °C when illuminated by a highly concentrated laser diode (LD) under driving current of 1000 mA, thus improving their optical performance. This work may pave a new way for next generation high-power QDs lighting applications.

Low carbon medium manganese steel with chromium and molybdenum addition (4MnCM), alongside a control group without these additions (4Mn), was developed. The quenching (860 °C) and tempering (620 °C) heat treatment process was applied to both steel groups. The influence of Cr and Mo on the microstructure evolution and mechanical properties was examined. The findings revealed that, the low−temperature impact energy values (KV2) of 4MnCM at −60 and −84 °C were enhanced by 104 and 107 J, in comparison to 4Mn. The yield and tensile strength saw an increase of 100 MPa. The higher low-temperature toughness of 4MnCM is attributed, on one hand, to the addition of Cr and Mo, which inhibiting deformation twinning through enhances the stacking fault energy (SFE) of reversed austenite. On the other hand, it is due to the absence of coarse ε−martensite (ε−m) along the crack propagation path. Additionally, the phase transformation of reversed austenite occurs at the crack nucleation stage during the impact process of both steels, which helps alleviate stress concentration and increases the energy required for crack formation. The primary reason for the higher strength of 4MnCM lies in the significant enhancement of precipitation strengthening effects through the precipitation of M6C, M23C6 and Nb/TiC co-precipitation with M6C.

The corrosion performance of martensitic steel remains a matter of dispute, with no consensus on whether it exhibits heightened or diminished corrosion resistance. In this study, the corrosion behavior and mechanism of martensitic steel were systematically investigated by simulating a cargo oil tank environment. The results indicate that under strong acidic conditions, the corrosion rate of martensite (1.1404 mm/y) is significantly higher than that of ferrite-pearlite (0.7430 mm/y) due to its increased dislocation density and internal stress. Additionally, the presence of high-energy defects provides abundant active sites for the redeposition of Cu-bearing particles, while their uneven distribution further exacerbates corrosion. Therefore, we propose a competitive mechanism that governs the corrosion behavior of martensite, complementing the understanding of its behavior and mechanism.

BackgroundStroke is a cerebrovascular disease with high prevalence and mortality, and upper limb hemiparesis is a major factor limiting functional recovery in stroke patients. Improvement of motor function in stroke patients through various forms of constraint-induced movement therapy (CITM) has been recognized as safe and effective in recent years. This research field lacks a comprehensive systematic and clear vein combing analysis, analyzing the literature research of CIMT in the field of rehabilitation in the past three decades, summarizing the research hotspots and cutting-edge trends in this field, in an effort to offer ideas and references for subsequent researchers.MethodsRelevant literature on CIMT in rehabilitation was collected from 1996 to 2024 within the Web of Science database’s core dataset by using CiteSpace6.1, VOSviewer1.6.18, R-bibliometrix4.6.1, Pajek5.16, Scimago Graphica 1.0.26 software for visualization and analysis.ResultsThere were 970 papers in all United States was ranked first with 401 papers. Alabama Univ was ranked first for institutions with 53 papers. Neurorehabilitation and Neural Repair was ranked first for journals with 78 papers, and Taub E was ranked first for author publications with 64 papers. Research keywords were CIMT, stroke rehabilitation, upper extremity function, lower extremity gait balance, randomized controlled trials, physical therapy techniques (transcranial magnetic stimulation and sensory amplitude electrical stimulation), primary motor cortex plasticity, lateral dominance (spatial behaviors), cerebral vascular accidents, activities of daily living, hand function, disability, functional restoration, bimanual training, aphasia, acquired invalidity, type A Botulinum toxin and joystick riding toys.ConclusionThe current state of research shows that CIMT still has a vast potential for development in the field of rehabilitation research. The research hotspots are the clinical efficacy of CIMT combined with other therapies (botulinum toxin type A, transcranial direct current stimulation, virtual reality, mirror therapy, robotic-assisted) to enhance the functionality of upper limb hemiparesis in stroke patients, the mechanism of CIMT to improve the plasticity of the motor cortex through electrophysiological and imaging methods, and improvement of lower limb gait balance function in stroke patients and aphasia applications, the optimal intervention time and dose, and exploration of CIMT in new settings such as robot-assisted, telemedicine, and home rehabilitation.

Abstract Wavelength-selective thermal emitters (WS-TEs) have been frequently designed to achieve desired target emissivity spectra, as a typical emissivity engineering, for broad applications such as thermal camouflage, radiative cooling, and gas sensing, etc. However, previous designs require prior knowledge of materials or structures for different applications and the designed WS-TEs usually vary from applications to applications in terms of materials and structures, thus lacking of a general design framework for emissivity engineering across different applications. Moreover, previous designs fail to tackle the simultaneous design of both materials and structures, as they either fix materials to design structures or fix structures to select suitable materials. Herein, we employ the deep Q-learning network algorithm, a reinforcement learning method based on deep learning framework, to design multilayer WS-TEs. To demonstrate the general validity, three WS-TEs are designed for various applications, including thermal camouflage, radiative cooling and gas sensing, which are then fabricated and measured. The merits of the deep Q-learning algorithm include that it can (1) offer a general design framework for WS-TEs beyond one-dimensional multilayer structures; (2) autonomously select suitable materials from a self-built material library and (3) autonomously optimize structural parameters for the target emissivity spectra. The present framework is demonstrated to be feasible and efficient in designing WS-TEs across different applications, and the design parameters are highly scalable in materials, structures, dimensions, and the target functions, offering a general framework for emissivity engineering and paving the way for efficient design of nonlinear optimization problems beyond thermal metamaterials.

The corrosion behavior of ship steel with different microstructure in a simulated tropical marine atmosphere was systematically investigated. Results show that homogeneous martensite structure obtained by water-quenching process was much more resistant to corrosion than that of ferrite-pearlite. Furthermore, the precipitation of carbide resulting from tempering process promoted the formation of corrosive microcells within the matrix and further intensified the corrosion. Rapid cooling rate led to the enrichment of chromium, which formed protective corrosion products such as FeCr2O4 and Cr(OH)3. This also facilitated the conversion of α-FeOOH and significantly enhanced the corrosion resistance.

Background Inconsistent results have been obtained regarding the association between return-to-sport (RTS) testing and the risk of subsequent re-injury following anterior cruciate ligament reconstruction (ACLR). We therefore conducted a systematic review and meta-analysis to assess the potential association between passing of RTS and the risk of re-injury for patients after ACLR. Methods This meta-analysis was registered in INPLASY with the registration number INPLASY202360027. The electronic databases MedLine, EmBase, and the Cochrane library were systematically searched to identify eligible studies from their inception up to September 2023. The investigated outcomes included knee injury, secondary ACL, contralateral ACL injury, and graft rupture. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using the random-effects model. Results A total number of nine studies involving 1410 individuals were selected for the final quantitative analysis. We noted that passing RTS test was not associated with the risk of subsequent knee injury (OR: 0.95; 95% CI: 0.28–3.21; P = 0.929), secondary ACL injury (OR: 0.98; 95% CI: 0.55–1.75; P = 0.945), and contralateral ACL injury (OR: 1.53; 95% CI: 0.63–3.71; P = 0.347). However, the risk of graft rupture was significantly reduced (OR: 0.49; 95% CI: 0.33–0.75; P = 0.001). Conclusions This study found that passing RTS test was not associated with the risk of subsequent knee injury, secondary ACL injury, and contralateral ACL injury, while it was associated with a lower risk of graft rupture. Thus, it is recommended that patients after ACLR pass an RTS test in clinical settings.

BackgroundPatellofemoral pain syndrome (PFPS) is a prevalent condition in sports medicine, and as sports competitions become more popular, the incidence of sports injuries is on the rise. Despite the increasing research on PFPS, there remains a lack of bibliometric analyses on this topic. The aim of this study was to identify the research hotspots and trends in the field of PFPS by reviewing 23 years of literature in this field.MethodsBy analyzing the literature on PFPS research from 2000 to 2023 in the core dataset of the Web of Science database and utilizing bibliometric tools like CiteSpace 6.1, VOSviewer 1.6.18, R-bibliometrix 4.6.1, Pajek 5.16, and Scimago Graphica 1.0.26, our aim was to gain insights into the current status and key areas of PFPS research. The study examined various aspects including the number of publications, countries, institutions, journals, authors, collaborative networks, keywords, and more. Through the visualization of relevant data, we also attempted to forecast future trends in the field.ResultsThere were 2,444 publications were included in this visualization study, published in 322 journals by 1,247 authors from 818 institutions in 67 countries. The Journal of Orthopaedic and Sports Physical Therapy had the highest number of publications, with the USA leading in article count. La Trobe University contributed the most articles, while Rathleff MS and Barton CJ emerged as the most prolific authors. Hip and knee strength and core strength, lower extremity kinematics and biomechanics, females (runners), muscle activation, risk factors, gait retraining, clinical practice guidelines, and rehabilitation were research hotspot keywords.ConclusionCurrent research suggests that there is still significant potential for the development of PFPS research. Key areas of focus include the clinical effectiveness of combined hip and knee strengthening to address PFPS, characterization of lower limb kinematics and biomechanics, gait retraining, risk factors, and clinical practice guidelines. Future research could explore the effectiveness of innovative exercise therapies such as blood flow restricting training, gait retraining, and neuromuscular control training for PFPS improvement. Further investigation into gait retraining for runners, particularly females, and clinical efficacy study of a novel PRP formulation for the treatment of PFPS.

This paper presents a comprehensive study of the impact of quenching roll speed on enhancing the low-temperature toughness of a low-carbon copper-containing steel. The microstructure characteristics, such as the prior austenite grains, and the distribution and volume fraction of precipitates, are observed using optical microscopy, scanning electron microscopy, transmission electron microscopy, and small-angle scattering X-ray. The results show that a decrease in the quenching roller speed (2 m/min) contributes to the achievement of more excellent low-temperature toughness (the average value is 232 J), although the prior austenite grains exhibit a relatively larger size in this case. The tempering treatment results in the precipitation of a large amount of 9R-type Cu-rich particles, regardless of the quenching roller speed. Reducing the quenching roller speed contributes to the increase in the volume fraction of Cu-rich particles, which is considered to be the main factor contributing to the achievement of excellent low-temperature toughness.

BackgroundIn recent years, research on the non-surgical treatment of AIS has been increasingly conducted. To the best of our knowledge, this field doesn't yet have a comprehensive and structured pulse combing analysis. In order to provide inspiration and resources for subsequent researchers, we thus reviewed the literature studies on the non-surgical treatment of AIS from the previous thirty years and highlighted the hotspots and frontiers of research in this field.MethodsMain using Citespace 6.1 software, the data from the core dataset of the WOS database pertaining to the non-surgical management of AIS from 1990 to 2022 was gathered, displayed, and analyzed.Results839 papers in all were included in the literature. With 215 papers, the USA came in first place. Chinese Univ Hong Kong ranked first with 32 papers. Research hotspots are adolescent idiopathic spondylitis, Schroth-based physiotherapy-specific exercise efficacy, curve development, Cobb angle, TLSO brace-based clinical efficacy, quality of life, reliability, health-related quality of life questionnaires, finite element biomechanical models, follow-up, and clinical guidelines.ConclusionThere aren't many studies that compare the clinical effectiveness of various non-surgical treatments, and because of variations in inclusion eligibility standards and outcome measures, these studies cannot be directly compared. In addition, the inconsistency of existing growth potential and progression risk assessment systems further affects comparative studies of clinical efficacy; it is recommended to establish primary assessment indicators centered on patient treatment outcomes (including appearance, disability, pain, and quality of life), as well as standardized scoliosis progression risk assessment criteria.

In this work we demonstrate how the current phase transition of atomic Bose–Einstein condensates in a toroidal trap can be controlled by applying a zero-mean oscillatory driving field. Here, the current phase transition means that the long-time averaged current undergoes a transition from a zero value to a nonzero value (or the transition from a nonzero value to a zero value). We show that due to the self-trapping effect in momentum space, the oscillatory amplitude of the current can be significantly suppressed and a nearly constant directed current can be obtained preserving the initial current values, by decreasing the driving amplitude, even when the atomic interactions are relatively small. We also reveal numerically the mean-field chaos can serve as an indicator of a quantum phase transition between the vanishing current regime and nonvanishing current regime. Our results are corroborated by an effective three-mode model, which provides an excellent account of the current dynamics of the system.

This study investigated the effects of reheating temperature on the microstructure and mechanical properties of Cu-containing 440 MPa grade non-tempered ship plate steel. The mechanical properties test, thermodynamic simulation, optical microscopy, scanning electron microscopy, transmission electron microscopy, and other tests were performed. The results revealed that with increasing reheating temperature, the ferrite grain size of Cu-containing 440 MPa non-tempered ship plate steel increased. Also, with increasing reheating temperature, the size of copper particles and niobium–titanium composite precipitates in the original austenite decreased. Consequently, this led to a weakening of the pinning effect on the original austenite and an increase in the size of the transformed ferrite grains. Moreover, with increasing reheating temperature, the number of Cu precipitates in the test steel after air cooling and rolling increased, while the size of the precipitates decreased, thereby weakening the solid solution strengthening effect of Cu, and precipitation was enhanced. Additionally, as the reheating temperature increased, the tensile strength and yield strength of the air-cooled test steel after rolling increased, while the impact toughness decreased.

In this work, two types of 590 MPa grade steels, composed of NiCrMo steel and Cu-bearing steel, were processed using traditional offline quenching and tempering and direct quenching (DQ) and tempering. The influence of DQ on microstructural evolution and strengthening mechanisms of these two types of steel was investigated. Grain refinement and dislocation density increase were determined by controlled rolling and following the DQ process in both two types of steel. In Cu-bearing steels, the refined grains and high-density dislocation further promoted the precipitation behavior of Cu-rich particles and alloyed carbides during the tempering treatment. Compared with traditionally quenched and tempered steels, NiCrMo steels after the direct quenching and tempering (DQT) process achieved 106 MPa higher yield strength through grain refinement strengthening and dislocation strengthening, while the Cu-bearing steels after the DQT process achieved 159 MPa higher yield strength through grain refinement strengthening, dislocation strengthening, and precipitation strengthening. The contribution degree of different strengthening mechanisms was quantitatively analyzed. Grain refinement also compensated for the toughness loss caused by the increase in dislocation, leading to an impact energy of 237 J and 248 J at −84 °C for NiCrMo and Cu-bearing steels after DQT, respectively.

The influence of varying the manganese (Mn) contents of high-strength copper-containing hull steel on its microstructural evolution and mechanical properties was investigated. With increasing Mn content from 2 to 5%, the tensile strength of the steel increased by ~100 MPa, while the elongation of steel remained at ~23.5%, indicating good plasticity. However, the 2Mn sample had 128 J higher low-temperature (−84 °C) impact work than the 5Mn sample. The microstructures of different Mn steels were composed of fresh martensite (FM), ferrite/tempered martensite (F/TM), and reversed austenite (RA). The increase in Mn content markedly increased the presence of RA and intensified the work hardening caused by the transformation-induced plasticity (TRIP) effect during the tensile process. However, as the phase transformation in different Mn steels occurred in the early stage of strain and did not extend throughout the entire plastic deformation process, increasing plasticity via phase transformation was difficult. In addition, although the volume fraction of RA increased significantly in 4Mn and 5Mn steels, the stability of RA significantly decreased. The presence of numerous metastable blocks and coarse lath-like RA contributed little to low-temperature impact work and was even detrimental to toughness. The substantial fresh martensite resulting from phase transformation facilitated microcrack generation, owing to rapid volume expansion and mutual impacts, thus reducing the work required for crack formation. Additionally, the abundance of deformation twins significantly reduced the work needed for crack propagation. These combined actions significantly reduced the low-temperature toughness of 4Mn and 5Mn steels.

A new system which combined cooling, heating and power (CCHP) and based on a solid oxide fuel cell (SOFC) with a LiBr absorption chiller and water tank is investigated. The influence of the working conditions of the SOFC on its steady-state and dynamic performances are studied. Meanwhile, the effects of working conditions of the stack and absorption chillers on multi-criteria assessments are also studied. The result shows that the operating temperature and current density can greatly affect the performance of the stack and system, which can also be influenced by the working conditions of the absorption chiller simultaneously. Increasing the operating temperature can greatly increase the electrical power, and the thermal power will be reduced correspondingly. Increasing the mass flows of the cooling, chilled and hot waters increase the cooling power and coefficient of performance (COP), thereby reducing the heating power.

We theoretically study the tunneling dynamics of two interacting spin–orbit-coupled (SOC) atoms trapped in a periodically perturbed double-well potential. We find that the phenomenon of coherent destruction of tunneling (CDT) can exist only for certain values of SOC, and two different mechanisms for the appearance of CDT are identified in this system. One is the conventional CDT resulting from quasi-energy degeneracy, while the other CDT originates from the dark Floquet state with zero quasi-energy for all values of the driving parameters. We discover that under double modulation combining the double-well potential shaking and a time-periodic Zeeman field, it is possible to realize spin-flipping single-atom Rabi tunneling and the CDT induced by the dark Floquet state at any value of SOC strength, which is not accessible with a single-drive field. Furthermore, we show that the detuning of Zeeman field with respect to the multiphoton energy is particularly significant in the case of the correlated two-particle tunneling mediated by SOC. We expect that these results will stimulate further exploration of the many-body dynamics in the interacting systems and expand the possibilities for manipulating the spin dynamics.

Abstract Antibacterial activity is one of the most vital characteristics for Titanium (Ti) dental implants. Coating antibacterial material onto Ti surfaces is an effective approach to enhance their intrinsic antibacterial ability. However, a cost-effective but efficient coating strategy for realizing this objective still remains challenging. In this study, we proposed a novel implant surface modification strategy for coating silver nanoparticles onto the porous Ti surface via a facile electron beam evaporation (EBE) approach. Porous Ti surfaces were firstly prepared by sand-blasting large grit acid-etching (SLA) process. Then, the silver nanoparticles coating thickness on the porous Ti surface was adjusted and optimized by altering the duration of EBE process. Consequently, composite porous Ti surfaces with different silver thicknesses were synthesized. Polished Ti (PT) surface without SLA or EBE process was also prepared as the controlled blank group. The surface characterizations were analyzed by SEM, AFM, and XPS. After that, the antibacterial properties of all groups were tested with bacteria counting method, bacterial viability test, live/dead bacterial staining, and SEM examination. Results show that silver nanoparticles were uniformly distributed on the porous Ti surfaces after the SLA and EBE processes. After being incorporated with silver nanoparticles, the composite surfaces successfully inhibited the growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The antibacterial ratio (AR) values of SLA-Ag groups increased with the increasing silver thickness and are significantly higher than those of PT and SLA groups. Therefore, by the SLA and EBE processes, the composite porous Ti surfaces modified with silver nanoparticles coatings demonstrate superior antibacterial property compared with pure Ti surfaces, which is highly promising for enhancing the antibacterial functions of dental implants. Graphical abstract

BackgroundIn sports medicine, tendon and ligament injuries are the most prevalent conditions, and with the booming of sports competition, the incidence of sports injuries is gradually increasing, investigating more potent therapeutic options is therefore becoming increasingly crucial. Platelet-rich plasma therapy has gained popularity as an effective and secure treatment in recent years. Currently, a faceted systematic and clear visual analysis is lacking in this research area.MethodsThe literature related to using platelet-rich plasma to treat ligament and tendon injuries from 2003 to 2022 in the core dataset of the Web of Science database was collected and analyzed visually using Citespace 6.1 software. Research hotspots and development trends were analyzed in terms of high-impact countries or regions, authors, research institutions, keywords, and cited literature.ResultsThe literature comprised a total of 1,827 articles. The annual publication volume of relevant literature has demonstrated a significant development tendency as the field of platelet-rich plasma research for tendon and ligament injuries has heated up in recent years. With 678 papers, the United States came in top place, followed by China with 187 papers. Hosp Special Surg ranked first with 56 papers. The hot research topics analyzed by keywords were tennis elbow, anterior cruciate ligament, rotator cuff repair, achilles tendon, mesenchymal stem cells, guided tissue regeneration, network meta analysis, chronic patellar tendinopathy, and follow up.ConclusionAnalysis of the research literature over the past 20 years shows that the United States and China will continue to dominate in terms of volume of publications based on annual volume and trends, with some collaboration among high-impact authors and further collaboration still needed in different countries and institutions. Platelet-rich plasma is widely used in the treatment of tendon ligament injuries. Its clinical efficacy is influenced by a number of factors, the main ones being the inconsistency in the preparation and composition of platelet-rich plasma and its related preparations, and the differences in efficacy due to different activation methods of platelet-rich plasma, as well as factors such as injection time, injection site, administration method, number of administrations, acidity and evaluation methods, In addition, the applicability to different injury diseases remains controversial. In recent years, the molecular biology of platelet-rich plasma for tendon ligament therapy has received increasing attention.

Purpose: To explore the effect of blood flow restriction training (BFRT) on the recovery of knee function in patients after arthroscopic partial meniscectomy (APM).Methods: Forty patients undergoing APM surgery were included in this parallel group, two-arm, single-assessor blinded, randomized clinical trial. The subjects were randomly divided into two groups: routine rehabilitation group (RR Group, n = 20) and routine rehabilitation + blood flow restriction training group (RR + BFRT Group, n = 20). One subject in each group dropped out during the experiment. All patients received 8 weeks of routine rehabilitation starting from the second day after APM. In addition, patients in the RR + BFRT group required additional BFRT twice a week. Visual analogue scale (VAS) score, range of motion (ROM), one-leg standing test (OLST) score, Lysholm knee score, quadriceps muscle strength, quadriceps thickness, and thigh circumference were evaluated at preoperative, postoperative, 4 and 8 weeks after surgery. SPSS 25.0 software was used for statistical analysis of the data. Repeated measures ANOVA was used if the data were normally distributed and had homogeneity of variance. Generalized estimating equations were chosen if the data were not normally distributed or had homogeneity of variance.Results: There were no significant differences in VAS score, ROM, OLST score, Lysholm knee score, quadriceps muscle strength, quadriceps thickness, and thigh circumference between the two groups before surgery (p > 0.05). Compared with postoperative, VAS score, ROM, OLST score, Lysholm knee score, and thigh circumference were significantly improved in the RR group (p < 0.05), while quadriceps muscle strength and quadriceps thickness were not significantly enhanced at 8 weeks postoperatively (p > 0.05). However, VAS score, ROM, OLST score, Lysholm knee score, quadriceps muscle strength, quadriceps thickness, and thigh circumference were all significantly improved in the RR + BFRT group at 8 weeks postoperatively (p < 0.05). Furthermore, compared with the RR group, VAS score (50% vs. 86%), ROM (7.9% vs. 16.0%), OLST score (57.3% vs. 130.1%), Lysholm knee score (38.4% vs. 55.7%), relative peak torque (11.0% vs. 84.7%), mean power (20.6% vs. 88.1%), rectus femoris thickness (0.40% vs. 13.0%), vastus medialis (0.29% vs. 5.32%), vastus lateralis (0% vs. 6.2%), vastus internus (0% vs. 5.8%), and thigh circumference (2.7% vs. 5.8%) in the RR + BFRT group were significantly improved at 4 and 8 weeks postoperatively (p < 0.05).Conclusion: BFRT combined with routine rehabilitation training can better promote the recovery of knee joint function in patients after APM, especially the improvement of quadriceps muscle strength and thickness.

In this paper, we present a rigorous analysis of symmetry and underlying physics of the nonlinear two-mode system driven by a harmonic mixing field, by means of multiple scale asymptotic analysis method. The effective description in the framework of the second-order perturbative theory provides an accurate picture for understanding the Floquet eigenspectrum and dynamical features of the nonlinear two-mode system, showing full agreement with the prediction of symmetry considerations. We find that two types of symmetries play significant role in the dynamical features of this model, the mechanism behind which can be interpreted in terms of the effective description. The results are of relevance for the phase control of the atomic localization in Bose–Einstein condensates or switch of the optical signals in nonlinear mediums.

In this study, microstructural evolution and its effects on mechanical properties across the thickness of a 120 mm Ni-Cr-Mo industrial ultra-heavy steel plate were quantitatively investigated by means of optical microscope (OM), scanning electron microscope (SEM), transmission electron microscope (TEM) and electron back-scatter diffraction (EBSD). The results show that the martensite fraction is 65% at 10 mm and disappears at 40 mm, while granular bainite appears at 35 mm and climbs up to as high as 32% at 60 mm, with M-A constituents significantly coarsened. The strength drops with the gradual coarsening of the laths as well as decreased martensite fraction from the surface to the centre. The toughness is mainly affected by the block size and the morphology and quantity of M-A constituents. This study established a multivariate function between the microstructure and toughness (50% fibre area transition temperature, FATT50) with careful consideration of the influence of effective grain size (EGS) and M-A constituent size distribution.

Translational regulation of isoforms in the developing nervous system is not well understood. Here, the authors report translational de-repression of RNA binding protein isoforms at their 5′UTRs in the neocortex and show the neurodevelopmental risk of post-transcriptional dysregulation.

Effective water management is particularly critical for fuel cells fed by hydrogen/oxygen. An ejector is an optimal device for the gas recirculation subsystem of a proton exchange membrane fuel cell (PEMFC) and is usually adopted for the auxiliary drainage of hydrogen/oxygen stacks. To explore the performance degradation of the fuel cells operating in dual ejector-based recirculation mode for both the anode and cathode, the dynamic characteristics of gas purging of the PEMFC was studied experimentally and the effects of the electrolyte and gas management strategy of the fuel cell on performance degradation were investigated in detail by using the measurement of polarization curves, electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and scanning electron microscopy (SEM) images of membrane electrode assembly (MEA) cross sections. The results indicated that the fuel cell with Nafion® 212 operating in the dual ejector-based recirculation mode has a better performance than that operating in the dead-ended mode, with total electrochemical surface area (ECSA) degradation rates of 10.61% and 17.02%, respectively. The ejector in the recirculation mode can accelerate the removal of liquid water from the fuel cell flow channel, avoiding water flooding and performance deterioration of fuel cells during long-term operation..

Sonoluminescence (SL) is an interesting physical effect which can convert acoustic energy into light pulses. Up to now, the microscopic mechanism of the SL has not yet been fully clear. It is known that hydroxyl radicals play the important role for SL from water. In this work, we take advantage of carbon nano-dots (CNDs) as free radical captors to modulate the hydroxyl radicals (OH·) in SL effect. Through studying the single bubble SL (SBSL) from CND aqueous solution (CNDAS) with trace amount of CNDs, we find that the color of SBSL is tuned dramatically from blue in water to green in CNDAS. Two different SL mechanisms can be identified from emission spectrum. One comes from blackbody-like radiation and another is attributed from the characteristic emission with identified peaks. The decrease in the yield of H2O2 in the presence of CNDs suggests the modulation effect on SL via OH· interacting with CNDs. By comparison of the CNDs before and after sonication, it is found that hydroxyl radicals generated during SL can take part in the chain-like oxidation of the chemical groups attached to the CNDs to form larger amount of carboxyl groups. The blackbody temperature of blackbody-like radiation decreases from 15,600 K in water to 11,300 K in CNDAS. Moreover, the emission from hydroxyl radicals and two new luminescent centers related to carboxyl groups are introduced in SL from CNDAS. These important and interesting findings indicate that by adding trace amount of CNDs in water, the effect of SBSL can be significantly modulated, which can provide a macroscopic phenomenon for gaining an insight into the microscopic mechanism of the SL effect.

The photoluminescent composite, which consists of micro-/nanoscale photoluminescent particles and a polymer matrix, plays a key role in optical wavelength conversion in white-light-emitting diodes (WLEDs). Heat is inevitably generated within the composite due to the energy lost through conversion and cannot be easily dissipated due to the extremely low thermal conductivity of the polymer matrix. Consequently, the composite suffers from a high working temperature, which severely deteriorates its optical performance as well as its long-term stability in WLEDs. To tackle this thermal issue, in this work three-dimensional (3D)-interconnected thermal conducting pathways composed of hexagonal boron nitride (hBN) platelets were constructed inside a photoluminescent composite, using a simplified bubbles-templating method. The thermal conductivity of the composite was efficiently enhanced from 0.158 to 0.318 W/(m∙K) under an ultralow hBN loading condition of 2.67 wt%. As a result, the working temperature of the photoluminescent composite in WLEDs was significantly reduced by 32.9 °C (from 102.3 °C to 69.4 °C, under 500 mA). Therefore, the proposed strategy can improve the heat accumulation issue in photoluminescent composites and thus improve the optical stability of WLEDs.

Thermal conductivity of material is one of the basic physical properties and plays an important role in manipulating thermal energy. In order to accelerate the prediction of material structure with desired thermal property, machine learning algorithm has been widely adopted. However, in the optimization of multivariable material structure such as different lengths or proportions, the machine learning algorithm may be required to be reconducted again and again for each variable, which will consume a lot of computing resources. Recently, it has been found that the thermal conductivity of aperiodic superlattices is closely related to the degree of the structural randomness, which can also be reflected in their local pattern structures. Inspired by these, we propose a new pattern analysis method, in which machine learning only needs to be carried out for one time, and through which the optimal structure of different variables with low thermal conductivity can be obtained. To verify the method, we compare the thermal conductivities of the structure obtained by pattern analysis, conventional machine learning, and previous literature, respectively. The pattern analysis method is validated to greatly reduce the prediction time of multivariable structure with high enough accuracy and may promote further development of material informatics.

This study examined the effect of boron (B) on the microstructure and toughness of the simulated coarse-grained heat-affected zone (CGHAZ) of normalized vanadium microalloyed offshore steel by using the welding thermal simulation method under different heat inputs for welding. The results showed that when t8/5 (the cooling time from 800 to 500 ∘C) increased from 14 s to 24 s, In the range of t8/5 of 24–44 s, the impact energy of the CGHAZ rose initially and then remained constant at around 125 J at −40 ∘C, and dropped to 79 J when t8/5 increased to 64 s. The particles (Ti,V)(C,N)-BN and BN contributed in the generation of acicular ferrite, which minimized the loss of CGHAZ toughness due to the presence of carbon. Furthermore, the microstructural parameters controlling CGHAZ toughness were the contents of the high misorientation grain boundaries and effective grain size at a tolerance angle of 15∘ at varied heat inputs.

This study investigated the precipitation behavior of nanoscale Cu and Ni3Al particles in multi-component ultra-high strength steel (UHSS) and its influence on mechanical properties. The precipitation nanostructural features and matrix microstructural features of UHSS were carefully characterized by HRTEM, XRD and EBSD. Addition of Cu and Al in Fe-Ni steel increased the dislocation density of martensite and promoted the co-precipitation of Cu and Ni3Al nanoparticles upon aging. The Fe-Ni-Cu-Al steel achieved a yield strength of 1350 MPa at 525 °C aging for 2 h, of which ~950 MPa is contributed by dislocation strengthening and co-precipitation strengthening. The dislocation density in experimental steels was determined in the range of 1015 m−2, which gave rise to a strengthening contribution of over 400 MPa. Meanwhile, the extremely high dislocation density acted as preferred precipitation sites for the co-precipitation of nanoscale Cu and Ni3Al particles. The contribution of co-precipitation strengthening was calculated as 413 MPa, while the contribution of strengthening relying on solely Cu precipitation in Fe-Ni-Cu steel was only 144 MPa. As increasing the aging temperature, Ni3Al particles showed faster coarsening rate than that of Cu particles, which led to a significant decrease in the strengthening increment of Fe-Ni-Cu-Al steel.

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer with a poor prognosis and limited therapeutic options. Alpha-fetoprotein (AFP), an established clinical biomarker of HCC, has been employed as an attractive target for T cell-based immunotherapy against this disease given its high expression in the tumor and restricted expression in normal tissues. We have identified a number of T cell receptors (TCRs) recognizing the HLA-A*02:01 restricted AFP158−166 peptide FMNKFIYEI, providing a TCR candidate pool for identifying TCRs with optimal clinical benefit. To select the ideal AFP TCR for clinical use, we evaluated the efficacy and safety profile of 7 TCRs by testing their potency toward AFP-expressing HCC cells and their specificity based upon reactivity to normal and transformed cells covering a wide variety of primary cell types and HLA serotypes. Furthermore, we assessed their cross-reactivity to potential protein candidates in the human genome by an extensive alanine scan (X-scan). We first selected three TCR candidates based on the in vitro anti-tumor activity. Next we eliminated two potential cross-reactive TCRs based on their reactivity against normal and transformed cells covering a variety of primary cell types and HLA serotypes, respectively. We then excluded the potential cross-reactivity of the selected TCR with a protein candidate identified by X-scan. At present we have selected an AFP TCR with the optimal affinity, function, and safety profile, bearing properties that are expected to allow AFP TCR redirected T cells to specifically differentiate between AFP levels on tumor and normal tissues. An early phase clinical trial using T cells transduced with this TCR to treat HCC patients (NCT03971747) has been initiated.

Autologous T cells engineered with T receptor genes (TCR) are being studied to treat cancers. We have recently identified a panel of mouse TCRs specific for the HLA-A0201/alpha fetoprotein epitope (AFP158) complex and have shown that human T cells engineered with these TCR genes (TCR-Ts) can eradicate hepatocellular carcinoma (HCC) xenografts in NSG mice. However, due to TCR’s promiscuity, their off-target cross-reactivity must be studied prior to conducting clinical trials. In this study, we conducted in vitro X-scan assay and in silico analysis to determine the off-target cross-reactivity of 3 AFP158-specific TCR-Ts. We found that the 3 AFP158-specific TCR-Ts could be cross-activated by ENPP1436 peptide and that the TCR3-Ts could also be activated by another off-target peptide, RCL1215. However, compared to AFP158, it requires 250 times more ENPP1436 and 10,000 times more RCL1215 peptides to achieve the same level of activation. The EC50 of ENPP1436 peptide for activating TCR-Ts is approximately 17–33 times higher than AFP158. Importantly, the ENPP1+ tumor cells did not activate TCR1-Ts and TCR2-Ts, and only weakly activated TCR3-Ts. The IFNγ produced by TCR3-Ts after ENPP1+ cell stimulation was >22x lower than that after HepG2 cells. And, all TCR-Ts did not kill ENPP1 + tumor cells. Furthermore, ectopic over-expression of ENPP1 protein in HLA-A2+ tumor cells did not activate TCR-Ts. In silico analysis showed that the ENPP1436 peptide affinity for HLA-A0201 was ranked 40 times lower than AFP158 and the chance of ENPP1436 peptide being processed and presented by HLA-A0201 was 100 times less likely than AFP158. In contrast, the two off-targets (Titin and MAGE-A3) that did cause severe toxicity in previous trials have the same or higher MHC-binding affinity and the same or higher chance of being processed and presented. In conclusion, our data shows that TCR-Ts can be activated by off-target ENPP1436 peptide. But, compared to target AFP158, it requires at least 250 times more ENPP1436 to achieve the same level of activation. Importantly, ENPP1436 peptide in human cells is not processed and presented to a sufficient level to activate the AFP158-specific TCR-Ts. Thus, these TCR-Ts, especially the TCR1-Ts and TCR2-Ts, will unlikely cause significant off-target toxicity.

We theoretically investigate light propagation in two coupled nonlinear waveguides with a certain static propagation constant detuning between two waveguides and with the linear refractive index modulated along the propagation direction. By slowly varying the amplitude of modulation, we steer the light to the desired output waveguide when equal amounts of lights are launched into each waveguide. We reveal that depending on the sign of the static propagation constant mismatch (detuning) between two waveguides, the launched light can be completely switched to either of waveguides. Additionally, we numerically examine the performances of light switching for general inputs and modulation amplitudes, and show that the localization of output light is robust against small to moderate variations in the final modulation amplitude, phase difference and intensity distribution of input field between two waveguides. More importantly, according to the principle of the proposed scheme, we are capable of steering the output light to the targeted waveguide at extremely low input power. In theory, our findings can be explained qualitatively by means of adiabatic navigation of the so-called nonlinear Floquet states. Keywords: Light tunneling, Adiabatic passage, Nonlinear waveguides

Cu-bearing age-hardening steel has significant potential in shipbuilding applications due to its excellent weldability as compared to conventional NiCrMoV steel. Not much research has been carried out to analyze the differences in the mechanisms of strength and toughness between Cu-bearing age-hardening and NiCrMoV steel. Both steels were heat treated under the same conditions: they were austenized at 900 °C and then quenched to room temperature, followed by tempering at 630 °C for 2 h. The uniaxial tensile test reveals that the Cu-bearing age-hardening steel exhibits relatively lower strength but larger plasticity than NiCrMoV steel. The lower contents of Carbon and other alloying elements is one of possible reasons for these differences in mechanical properties. Transmission Electron Microscope observations show that two types of precipitates, Cr carbides and Cu-rich particles, exist in tempered Cu-bearing age-hardening steel. Cu-rich particles with sizes of 20–40 nm can inhibit the dislocation motion during deformation, which then results in dislocation pile ups and multiplication; this makes up the strength loss of Cu-bearing age-hardening steel and simultaneously improves its plasticity.

When an object is illuminated, part of the incident light is absorbed by the object that does not contribute to the illumination. If the light source's spectrum can be optimized by decreasing the light energy along the absorbed wavelengths, substantial energy can be saved. In this study, a spectrum optimization method by means of a genetic algorithm to minimize the light energy along the absorbed wavelengths while maintaining the light quality of the light source was proposed. Under the constraint that the color differences of the object illuminated by the optimized illuminant and the reference illuminant do not exceed specified levels, maximum energy saving ratio (ESR) is achieved for various reference illuminants. It is found that through the proposed method effectively saving the energy, for a monochromatic object, the ESR can reach 49.5% with barely recognizable color difference, whereas for a polychromatic object, the ESR can reach 55.2% with an acceptable color difference for each patch of the object.

Low light efficiency and poor angular color uniformity (ACU) are the key challenges of chip-on-board packaging light-emitting diodes (LEDs). In this paper, we demonstrate a phosphor geometry, and its controlling method for enhancing the optical performance of chip-on-board packaging LEDs, its fabrication flexibility, and availability are validated by experiments, and its effect on the optical performance is analyzed by optical simulations and experiments. The simulation results show that compared with the conventional flat geometry, the cylindrical tuber geometry can effectively improve the light efficiency and ACU, and the light efficiency enhancement increases with correlated color temperature. Experimental results show that for the case that the encapsulation layer only consists of silicone, the proposed geometry enhances the light efficiency up to 63.1%. In addition, for another case, in which the encapsulation layer consists of silicone and phosphor particles, when the average correlated color temperature (CCT) is about 5000 K, the proposed geometry increases the light efficiency by 11.7%, and the angular CCT deviations for the flat geometry and the proposed geometry are 1805 and 475 K, respectively.

In this paper, we study how to apply a periodic driving field to control stable spin tunneling in a non-Hermitian spin–orbit (SO) coupled bosonic double-well system. By means of a high-frequency approximation, we obtain the analytical Floquet solutions and their associated quasienergies and thus construct the general non-Floquet solutions of the dissipative SO coupled bosonic system. Based on detailed analysis of the Floquet quasienergy spectrum, the profound effect of system parameters and the periodic driving field on the stability of spin-dependent tunneling is investigated analytically and numerically for both balanced and unbalanced gain–loss between two wells. Under balanced gain and loss, we find that the stable spin-flipping tunneling is preferentially suppressed with the increase of gain–loss strength. When the ratio of Zeeman field strength to periodic driving frequency Ω/ ω is even, there is a possibility that continuous stable parameter regions will exist. When Ω/ ω is odd, nevertheless, only discrete stable parameter regions are found. Under unbalanced gain and loss, whether Ω/ ω is even or odd, we can get parametric equilibrium conditions for the existence of stable spin tunneling. The results could be useful for the experiments of controlling stable spin transportation in a non-Hermitian SO coupled system.

Smoke detection technology based on computer vision is a popular research direction in fire detection. This technology is widely used in outdoor fire detection fields (e.g., forest fire detection). Smoke detection is often based on features such as color, shape, texture, and motion to distinguish between smoke and non-smoke objects. However, the salience and robustness of these features are insufficiently strong, resulting in low smoke detection performance under complex environment. Deep learning technology has improved smoke detection performance to a certain degree, but extracting smoke detail features is difficult when the number of network layers is small. With no effective use of smoke motion characteristics, indicators such as false alarm rate are high in video smoke detection. To enhance the detection performance of smoke objects in videos, this paper proposes a concept of change-cumulative image by converting the YUV color space of multi-frame video images into a change-cumulative image, which can represent the motion and color-change characteristics of smoke. Then, a fusion deep network is designed, which increases the depth of the VGG16 network by arranging two convolutional layers after each of its convolutional layer. The VGG16 and Resnet50 (Deep residual network) network models are also arranged using the fusion deep network to improve feature expression ability while increasing the depth of the whole network. Doing so can help extract additional discriminating characteristics of smoke. Experimental results show that by using the change-cumulative image as the input image of the deep network model, smoke detection performance is superior to the classic RGB input image; the smoke detection performance of the fusion deep network model is better than that of the single VGG16 and Resnet50 network models; the smoke detection accuracy, false positive rate, and false alarm rate of this method are better than those of the current popular methods of video smoke detection.

Directional heat transfer may be hard to realize due to the fact that heat transfer is diffusive. In this paper, we try to take one step forward based on the transformation thermodynamics. A special structure and meta-device is proposed to “reflect” the heat flow directionally–just like the mirror to the light beam, in which the heat flow just one-time changes the direction rather than gradually changing the directions in isotropic materials. The benefits of such thermal reflection meta-device are discussed by comparing the corresponding thermal resistance with the same structures of isotropic materials. The proposed meta-device is verified to possess the low thermal resistance and high heat transfer ability with least energy loss, and can be made by nature-existing isotropic materials with specific structures.

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with a strong genetic predisposition, characterized by an upregulated type I interferon pathway. MicroRNAs are important regulators of immune homeostasis, and aberrant microRNA expression has been demonstrated in patients with autoimmune diseases. We recently identified miR-146a as a negative regulator of the interferon pathway and linked the abnormal activation of this pathway to the underexpression of miR-146a in SLE patients. To explore why the expression of miR-146a is reduced in SLE patients, we conducted short parallel sequencing of potentially regulatory regions of miR-146a and identified a novel genetic variant (rs57095329) in the promoter region exhibiting evidence for association with SLE that was replicated independently in 7,182 Asians (P(meta) = 2.74×10(-8), odds ratio = 1.29 [1.18-1.40]). The risk-associated G allele was linked to reduced expression of miR-146a in the peripheral blood leukocytes of the controls. Combined functional assays showed that the risk-associated G allele reduced the protein-binding affinity and activity of the promoter compared with those of the promoter containing the protective A allele. Transcription factor Ets-1, encoded by the lupus-susceptibility gene ETS1, identified in recent genome-wide association studies, binds near this variant. The manipulation of Ets-1 levels strongly affected miR-146a promoter activity in vitro; and the knockdown of Ets-1, mimicking its reduced expression in SLE, directly impaired the induction of miR-146a. We also observed additive effects of the risk alleles of miR-146a and ETS1. Our data identified and confirmed an association between a functional promoter variant of miR-146a and SLE. This risk allele had decreased binding to transcription factor Ets-1, contributing to reduced levels of miR-146a in SLE patients.

We study a system of three coherently coupled states, where one state is shifted periodically against the other two. We discover that this system possesses a dark Floquet state that has zero quasi-energy and negligible population at the intermediate state. This dark Floquet state manifests itself dynamically in terms of the suppression of inter-state tunneling, a phenomenon known as coherent destruction of tunneling (CDT). Owing to its different origin from the CDT found in a two-state-driven system, we call it dark CDT. At a high-frequency limit for the periodic driving, this Floquet state reduces to the well-known dark state. Our results can be generalized to systems with more states and be verified with easily implemented experiments within the current technologies.

Objective: To prove that the "sports rehabilitation bed" is a device aimed at improving the precision of stretching, which can help to reduce the difficulty of rehabilitation therapy, cut down the manpower input of rehabilitation therapy, and shorten the therapy duration as well. Methods: This was a clinical comparative study. Twenty patients who underwent stretching therapy in Sichuan Province Orthopedic Hospital from June 2020 to August 2020 were randomly selected to carry out a control study on both lower extremities. The experimental group was given sports rehabilitation bed to assist rehabilitation therapy, while the control group was given conventional bare-handed stretching rehabilitation therapy. The stretching angle, stretching value, and the effective rate of stretching therapy between the two groups to analyze the clinical value of the new sports rehabilitation therapy bed. Results: The stretching angle in the experimental group when using the sports rehabilitation therapy bed for stretching was lower than the conventional bare-handed stretching in the control group (T<0, P=0.05), with a statistically significant difference; the stretching values of the experimental group were lower than those of the control group(P<0.01), with a statistically significant difference. Moreover, the response rate of stretching therapy in the experimental group was lower than that in the control group(P<0.05), with a statistically significant difference. Conclusion: Sports rehabilitation therapy beds can results in the advantages of effectively preventing iatrogenic injury in the process of stretching, and providing a more accurate and convenient stretching therapy method than the current commonly used bare-handed stretching for sports rehabilitation and intervention. [ABSTRACT FROM AUTHOR]