External fields effectively switch the spin channels of transition metal-doped ß-phase tellurene from first principles.

Non-volatile magnetic random-access memories have proposed the need for spin channel switching. However, this presents a challenge as each spin channel reacts differently to the external field. Tellurene is a semiconductor with a tunable bandgap, excellent stability, and high carrier concentration, but its lack of magnetic properties has hindered its application in spintronics. In this work, the influence of an external field on transition metal (TM)-doped ß-tellurene is systematically analysed from first principles. First, the active-learning moment-tensor-potential (MTP) is used to verify the thermal stability of the V-doped system with the MTP proving to be 900 times faster than the traditional method. Subsequently, under biaxial strain ranging from -2% to 10%, the V-doped system undergoes a gradual transition from a magnetic semiconductor to a spin-gapless semiconductor, and further to a half-metal and magnetic metal. The band structure can be maintained under an electric field. By examining the magnetic anisotropy energy, the lattice changes profoundly impact the electromagnetic properties, particularly with the TMs being sensitive to strain. Moreover, the band structure is reflected in the spin resolution current of the magnetic tunnel junction. This work investigates the response of doped ß-Te to external fields, revealing its potential applications in spintronics.

Interface engineering strategy for multisource spintronic devices via TMPS4 modulation of black-phosphorus.

Interface engineering is an effective strategy for significantly providing performance improvements in logic operations and information storage techniques, given the quantum effects characteristic of pristine two-dimensional ferromagnetic (FM) materials. Furthermore, the van der Waals (vdW) heterostructures enable a more efficient design of logic components. Herein, two novel designs of van der Waals heterostructures are proposed, black-phosphorus (BP)/TMPS4(TM = Cr, Fe-Mn), where the CrPS4 relies on odd and even layers for FM state - antiferromagnetic (AFM) state alternation, which is used to modulate BP with high hole mobility but no magnetism. Based on the first principles, the simulation results show that the two heterojunctions exhibit high stability, carrier mobility, and thermoelectric effects, of which the BP/CrPS4 heterojunction is specifically modulated to a type II electronic bandstructure. These two structures are applied in multi-source logic devices. The device performances show that the devices have spin Sebeck effect (SSE), perfect spin filtering effect (SFE), high extinction ratio (1347), and high thermal magnetoresistivity (1011). The above results suggest BP/TMPS4 bilayers as promising candidates for spin-based vdW devices and facilitate the future development of atomically thin magnetic information storage.

Spin-gapless van der Waals heterostructure for spin gating through magnetic injection devices.

Spin-gapless semiconductors (SGSs) are new magnetic zero-bandgap materials whose band structure is extremely sensitive to external influences (pressure or magnetic fields) and have great potential for high-speed and low-energy spintronics applications. The first-principles method was used to systematically study the heterostructures constructed of an asymmetric surface-functionalized Janus MXene material, Cr2NOF, and a two-dimensional hexagonal lattice (2DH) semiconductor material and to study the effects of the electronic structure, Curie temperature, magnetism, and the design of unusual band structures and magnetic injection in the bilayer to obtain an SGS structure. Through the design and construction of Cr2NOF/2DH van der Waals heterojunction spintronic devices, the spin-filtering effect of the devices can reach 100%, especially, realizing spin gating through magnetic injection. We report the transport mechanism of the heterojunction spintronic devices to achieve the goal of a controllable optimization of the device functions, which provides a theoretical basis for the design of MXene van der Waals heterojunctions for high-efficiency and low-power-consumption spintronic devices.

A UWB/INS Trajectory Tracking System Application in a Cycling Safety Study.

This paper focuses on the safety issue for cyclists and pedestrians at unsignalized intersections. The cycling speed needs to be calmed when approaching the intersection. This study proposes and deploys an integrated portable ultra-wideband/inertial navigation system (UWB/INS) to extract cycling trajectories for a cycling safety study. The system is based on open-source hardware and delivers an open-source code for an adaptive Kalman filter to enhance positioning precision for data quality assurance at an outdoor experimental site. The results demonstrate that the system can deliver reliable trajectories for low-mobility objects. To mitigate accident risk and severity, varied cycling speed calming measures are tested at an experimental site. Based on the trajectory data, the statistical features of cycling velocities are evaluated and compared. A new proposed geometric design is found to be most effective when compared with conventional traffic signs.

Association between different MAP levels and 30-day mortality in sepsis patients: a propensity-score-matched, retrospective cohort study.

BACKGROUND: Sepsis is a life-threatening organ dysfunction caused by the infection-related host response disorder. Adequate mean arterial pressure is an important prerequisite of tissue and organ perfusion, which runs through the treatment of sepsis patients, and an appropriate mean arterial pressure titration in the early-stage correlates to the positive outcome of the treatment. Therefore, in the present study, we aimed to elucidate the relationship between early mean arterial pressure levels and short-term mortality in sepsis patients. METHODS: We included all suspected sepsis patients from MIMIC-III database with average mean arterial pressure ≥ 60 mmHg on the first day of intensive care unit stay. Those patients were then divided into a permissive low-mean arterial pressure group (60-65 mmHg) and a high-mean arterial pressure group (> 65 mmHg). Multivariate Cox regression analysis was conducted to analyze the relationship between MAP level and 30-day, 60-day, and 100-day mortality of suspected sepsis patients in the two groups. Propensity score matching, inverse probability of treatment weighing, standardized mortality ratio weighting, PA weighting, overlap weighting, and doubly robust analysis were used to verify our results. RESULTS: A total of 14,031 suspected sepsis patients were eligible for inclusion in our study, among which 1305 (9.3%) had an average first-day mean arterial pressure of 60-65 mmHg, and the remaining 12,726 patients had an average first-day mean arterial pressure of more than 65 mmHg. The risk of 30-day mortality was reduced in the high mean arterial pressure group compared with the permissive low-mean arterial pressure group (HR 0.67 (95% CI 0.60-0.75; p < 0.001)). The higher mean arterial pressure was also associated with lower 60-day and 100-day in-hospital mortality as well as with shorter duration of intensive care unit stay. Patients in the high-mean arterial pressure group also had more urine output on the first and second days of intensive care unit admission. CONCLUSIONS: After risk adjustment, the initial mean arterial pressure of above 65 mmHg was associated with reduced short-term mortality, shorter intensive care unit stay, and higher urine volume in the first two days among patients with sepsis.

Adaptive correction method of hybrid aberrations in Fourier ptychographic microscopy.

Significance: Fourier ptychographic microscopy (FPM) enables quantitative phase imaging with a large field-of-view and high resolution by acquiring a series of low-resolution intensity images corresponding to different spatial frequencies stitched together in the Fourier domain. However, the presence of various aberrations in an imaging system can significantly degrade the quality of reconstruction results. The imaging performance and efficiency of the existing embedded optical pupil function recovery (EPRY-FPM) aberration correction algorithm are low due to the optimization strategy. Aim: An aberration correction method (AA-P algorithm) based on an improved phase recovery strategy is proposed to improve the reconstruction image quality. Approach: This algorithm uses adaptive modulation factors, which are added while updating iterations to optimize the spectral function and optical pupil function updates of the samples, respectively. The effectiveness of the proposed algorithm is verified through simulations and experiments using an open-source biological sample dataset. Results: Experimental results show that the proposed AA-P algorithm in an optical system with hybrid aberrations, recovered complex amplitude images with clearer contours and higher phase contrast. The image reconstruction quality was improved by 82.6% when compared with the EPRY-FPM algorithm. Conclusions: The proposed AA-P algorithm can reconstruct better results with faster convergence, and the recovered optical pupil function can better characterize the aberration of the imaging system. Thus, our method is expected to reduce the strict requirements of wavefront aberration for the current FPM.

GPX2 is a potential therapeutic target to induce cell apoptosis in lenvatinib against hepatocellular carcinoma.

INTRODUCTION: Lenvatinib has recently become available as the first-line therapy for advanced hepatocellular carcinoma (HCC), but its molecular mechanism in HCC remains largely unknown. OBJECTIVES: The current study aims to identify the molecular mechanisms of lenvatinib in HCC. METHODS: Gene expression microarrays, flow cytometry, western blot, qRT-PCR, immunohistochemistry and immunofluorescence were used to study the response of HCC cells to lenvatinib. Xenograft tumor of Huh7 cells was also established to detect the effect of lenvatinib in vivo. RESULTS: Herein, we found that lenvatinib could induce apoptosis via increasing reactive oxygen species (ROS) levels in HCC cells. Then, microarray analysis and qRT-PCR results confirmed that GPX2 was a vital target for lenvatinib against HCC. Loss and gain function of experiment showed that regulating GPX2 levels markedly affected the lenvatinib-induced ROS levels and apoptosis in HCC cells. In addition, analyses of The Cancer Genome Atlas database and the qRT-PCR results in our cohort both showed that GPX2 markedly overexpressed in tumor tissues and correlated with poor overall survival in HCC. Mechanistically, our findings further demonstrated that GPX2 was a downstream gene regulated by ß-catenin, while lenvatinib could prevent nuclear translocation of ß-catenin and further inhibit GPX2 expression in HCC cells. More importantly, the correlation of GPX2 expression with lenvatinib response was further analyzed in 22 HCC patients who received lenvatinib therapy, and the results showed that the objective response rate (ORR) in patients with low GPX2 expression was 44.4% (4/9), while the ORR in patients with high GPX2 levels was only 7.7% (1/13). CONCLUSION: Our findings indicated that GPX2 plays an important role in lenvatinib-induced HCC cell apoptosis, which might serve as a biomarker for instruction of lenvatinib therapy in HCC patients.

Quasi-2D Mn3Si2Te6 Nanosheet for Ultrafast Photonics.

The magnetic nanomaterial Mn3Si2Te6 is a promising option for spin-dependent electronic and magneto-optoelectronic devices. However, its application in nonlinear optics remains fanciful. Here, we demonstrate a pulsed Er-doped fiber laser (EDFL) based on a novel quasi-2D Mn3Si2Te6 saturable absorber (SA) with low pump power at 1.5 µm. The high-quality Mn3Si2Te6 crystals were synthesized by the self-flux method, and the ultrathin Mn3Si2Te6 nanoflakes were prepared by a simple mechanical exfoliation procedure. To the best of our knowledge, this is the first time laser pulses have been generated using quasi-2D Mn3Si2Te6. A stable pulsed laser at 1562 nm with a low threshold pump power of 60 mW was produced by integrating the Mn3Si2Te6 SA into an EDFL cavity. The maximum power of the output pulse is 783 µW. The repetition rate can vary from 24.16 to 44.44 kHz, with corresponding pulse durations of 5.64 to 3.41 µs. Our results indicate that the quasi-2D Mn3Si2Te6 is a promising material for application in ultrafast photonics.

Reduction in required volume of imaging data and image reconstruction time for adaptive-illumination Fourier ptychographic microscopy.

Fourier ptychographic microscopy (FPM) is a promising super-resolution computational imaging technology. It stitches a series of low-resolution (LR) images in the Fourier domain by an iterative method. Thus, it obtains a large field of view and high-resolution quantitative phase images. Owing to its capability to perform high-spatial bandwidth product imaging, FPM is widely used in the reconstruction of conventional static samples. However, the influence of the FPM imaging mechanism limits its application in high-speed dynamic imaging. To solve this problem, an adaptive-illumination FPM scheme using regional energy estimation is proposed. Starting with several captured real LR images, the energy distribution of all LR images is estimated, and select the measurement images with large information to perform FPM reconstruction. Simulation and experimental results show that the method produces efficient imaging performance and reduces the required volume of data to more than 65% while ensuring the quality of FPM reconstruction.

Multiconfiguration b-AsP-based doping systems with enriched elements (C and O): novel materials for spintronic devices.

Black arsenical phosphorus (b-AsP), a derivative of black phosphorus, is a bimetallic alloy compound with the advantage of high carrier mobility, high stability, and tailorable configuration. However, lack of an effective tool to facilitate the application of AsP as a magnetic device. Herein, band gap modulation and the introduction of magnetism can be achieved by doping non-metallic atoms in three different AsP configurations. And the doping of the same atom will cause variation in the electronic structure depending on the configuration. Surprisingly, doping with both enriched elements C and O transforms AsP into a magnetic material. Furthermore, the source of the magnetic moment is explained by solving the wave function of the doped AsP, which is caused by the orbital coupling of the C and O atoms to AsP. To excavate the potentials of this magnetic AsP system for magnetic devices, field-effect transistors based on two doped armchair AsP3 nanoribbons are simulated. The devices show considerable negative differential conductivity effect and good spin filtering efficiency. These findings suggest that AsP doping with enriched elements C and O could be an excellent candidate for future spintronics applications.

Bimetallic Alloys b-AsxP1-x at High Concentration Differences: Ideal for Photonic Devices.

Black arsenic phosphorus (b-AsxP1-x) is expected to be one of the primary materials for future photonic devices. However, the x-factor is randomly estimated and applied in photonic devices in current studies, rather than systematically analyzing it for a comprehensive understanding. Herein, AsxP1-x switches from a direct band gap semiconductor to an indirect band gap one at x = 0.75. AsxP1-x at x ≤ 0.25 is capable of broadband absorption, while b-AsxP1-x at x ≥ 0.75 can only absorb at specific wavelengths in the perspective of the electron energy transition. Additionally, the optoelectronic response of the integral field-effect transistor configurations constructed with b-AsxP1-x is investigated systematically as a photodetector device. The photonic response characteristics show high polarization sensitivity at x ≥ 0.75, but a typical circuit system signal at x ≤ 0.25. These results suggest that b-AsxP1-x with high concentration differences is a perfect candidate for photonic material.

Fast and stable Fourier ptychographic microscopy based on improved phase recovery strategy.

Fourier ptychographic microscopy (FPM) imaging is a computational imaging technology that can reconstruct wide-field high-resolution (HR) images. It uses a series of low-resolution images captured by a camera under different illumination angles. The images are stitched in the Fourier domain to expand their spectral range. Under high-angle illumination, a dark-field image is noisy with a low signal-to-noise ratio, which significantly reduces the reconstruction quality of FPM. Conventional reconstruction algorithms often have low FPM imaging performance and efficiency due to optimization strategies. In response to these problems, this paper proposes an FPM imaging method based on an improved phase recovery strategy to optimize the alternating iterative algorithm. The technique uses an improved threshold method to reduce noise in the image preprocessing stage to maximize the retention of high-frequency sample information. Moreover, an adaptive control factor is added in the subsequent iterative update process to balance the sample spectrum function. This study verifies the effectiveness of the proposed method on both simulation and experimental images. The results show that the proposed method can effectively suppress image background noise and has a faster convergence speed and higher robustness. In addition, it can be used to reconstruct HR complex amplitude images of objects under wide field-of-view conditions.

A first-principles study of the ultra-high spin rectification effect based on nitride MXenes (Sc2NO2, Ti2NO2).

Nitride MXenes exhibit inherent strong chemical stability and ferromagnetic properties, which are significant for their application in nanoscale spintronic devices. To demonstrate the potential of nitride MXenes in spintronics, we have designed a Sc2NO2/Ti2NO2 heterojunction and investigated its spin transport properties using first principles calculations combined with the non-equilibrium Green's function. The results show that the Sc2NO2/Ti2NO2 heterojunction has a stable negative differential resistance effect and a great spin rectification effect with a rectification ratio of 1.73 × 1011. The corresponding energy band structures and the transport behavior establish the mechanism for such properties. In addition, the perfect two-dimensional morphology provides a suitable nanostructured material for developing spintronic devices.

Potential outstanding physical properties of novel black arsenic phosphorus As0.25P0.75/As0.75P0.25 phases: a first-principles investigation.

Black arsenic phosphorus As0.5P0.5 has been studied as an excellent candidate for electronic and optoelectronic applications. At the same time, the physical properties of As x P1-x alloys with other compositions were not investigated. In this work, we design seven As0.25P0.75(P-I and P-II)/As0.75P0.25(As-(I, II, III, IV and V)) phases with molecular dynamics stability. First principles calculations are used to study their electronic structures under strain as well as their carrier mobilities. By calculating Perdew-Burke-Ernzerhof (PBE) electronic bands, we reveal that these materials are direct-gap semiconductors similar to black phosphorus except for the As-IV phase. It is also found that the carrier mobility in the P-I and As-V phases can reach 104 cm2 V-1 s-1. The electronic structures of the P-I, As-IV and As-V phases under strain are studied. Finally, we design caloritronic devices based on armchair and zigzag nanoribbons. The value of the Seebeck coefficient of the armchair and zigzag devices made from the P-II phases are found to be as high as 2507 and 2005 µW K-1 at 300 K. The thermal properties of the arsenic phosphorus phases under consideration are further studied by calculating their thermoelectric figure of merit, ZT values. These values are as high as 10.88 for the armchair devices based on the As-III phase and 4.59 for the zigzag devices based on the As-V phase at room temperature, and 15 and 7.16 at 600 K, respectively. The obtained results demonstrate that the As0.25P0.75/As0.75P0.25 phases studied here can be regarded as potential candidates for thermoelectric and electronic device applications.

High Expression of Long Non-Coding RNA TMCO1-AS1 is Associated With Poor Prognosis of Hepatocellular Carcinoma.

Background: The molecular pathways along with the clinical significance of long non-coding RNAs (lncRNAs) in hepatocellular carcinoma (HCC) remain uncertain. Our study sought to identify and characterize lncRNAs associated with HCC. Methods: LncRNA TMCO1-AS1 was identified by differential expression analysis, receiver operating characteristic (ROC) analysis, and univariate analysis using RNA sequencing and clinical information of HCC from the public database. Then clinical correlations and survival analysis were conducted to further appraise the prognostic significance of lncRNA TMCO1-AS1 in HCC. Hepatoma and adjoining normal tissues from 66 patients who received surgical operation at our center were used to verify the results of the bioinformatics analysis. A survival prognostic model was established combining TMCO1-AS1 expression and other clinical characteristics. Results: Bioinformatics analysis showed the aberrant high expression of TMCO1-AS1 in HCC tissue. TMCO1-AS1 expression was positively correlated with alpha-fetoprotein (AFP) level, vascular invasion, tumor stage, as well as tumor differentiation. Moreover, survival analysis found a significant inverse association between the expression of TMCO1-AS1 and the survival of patients with HCC. Cox analysis indicated that TMCO1-AS1 was an independent factor for HCC prognosis. Analysis of the HCC tissues from patients at our center provided results similar to those of the bioinformatics analysis. Risk models for overall survival (OS) and recurrence-free survival (RFS) incorporating TMCO1-AS1 exhibited better sensitivity and specificity than using clinical characteristics alone. Conclusion: High TMCO1-AS1 expression is significantly correlated with the unfavorable poor prognosis of HCC, indicating its potential of being a novel prognostic marker for HCC.

Synthesis of Hexagonal Structured GaS Nanosheets for Robust Femtosecond Pulse Generation.

Gallium sulfide (GaS), with a hexagonal structure, has received extensive attention due to its graphene-like structure and derived optical properties. Here, high-quality GaS was obtained via chemical vapor synthesis and then prepared as a saturable absorber by the stamp-assisted localization-transfer technique onto fiber end face. The stability of the material and the laser damage threshold are maintained due to the optimized thickness and the cavity integration form. The potential of the GaS for nonlinear optics is explored by constructing a GaS-based Erbium-doped mode-locked fiber laser. Stable femtosecond (~448 fs) mode-locking operation of the single pulse train is achieved, and the robust mode-locked operation (>30 days) was recorded. Experimental results show the potential of GaS for multi-functional ultrafast high-power lasers and promote continuous research on graphene-like materials in nonlinear optics and photonics.

Femtosecond ultrafast pulse generation with high-quality 2H-TaS2 nanosheets via top-down empirical approach.

Tantalum disulfide (TaS2), an emerging group VB transition metal dichalcogenide, with unique layered structure, rich phase diagrams, metallic behavior, higher carrier concentration and mobility is emerging as a prototype for revealing basic physical phenomena and developing practical applications. However, its photonics properties and even engineering-related processes are still rare. Here, the top-down experiment demonstration, including synthesis, thickness optimization and nonlinear optical application, has been reported. In addition, the ultrafast (∼373 fs) erbium-doped fiber pulse with a small time-bandwidth product (∼0.34) and long-term stability (∼25 days) was realized using the nonlinear absorption properties of the high-quality 2H-TaS2 nanosheet. These results suggest an experimental route for further ultrafast photonics exploration based on metallic transition metal dichalcogenides.

The electromagnetic performance of transition metal-substituted monolayer black arsenic-phosphorus.

Recently, a new two-dimensional nonmagnetic semiconductor material, black arsenic-phosphorus (bAsP), has gained great research attention for experimental and theoretical works owing to its excellent physical properties. The present work attempted to investigate the electromagnetic properties of three 1 : 1 bAsP structures (bAsP-1, bAsP-2, and bAsP-3) substituted with transition metals (TM) by using first principles. Among these substituted bAsP systems, V substitutes P of bAsP-1, Ni substitutes As of bAsP-1, Mn substitutes P of bAsP-2, Fe substitutes As of bAsP-2 and Mn substitutes P of bAsP-3 and these are found to be half-metals. Among them, the system where Ni substitutes As of the bAsP-1 shows the largest binding energy and is the most stable structure. The system where one Ni atom substitutes As of bAsP-1 (As_Ni) and the system where two Ni atoms substitute As of bAsP-1 (2As_2Ni) are selected to develop magnetic tunnel junctions where it is found that the increase in the concentration of Ni in the electrodes increases the spin polarized current. More interestingly, a perfect spin filtering effect with 100% spin polarization and tunnel magnetoresistance of above 104% can be obtained in the one Ni substituted-system (As_Ni) and two Ni-substituted system (2As_2Ni). The negative differential resistance ratio is as high as 3.2 × 107% when the voltage is 0.5 V in the parallel spin configuration of As_Ni. The present research displays that the TM-substituted bAsP structure can be used in the fabrication of spintronic devices.

Sub-Band Gap Absorption and Optical Nonlinear Response of MnPSe3 Nanosheets for Pulse Generation in the L-Band.

Two-dimensional (2D) materials have attracted extensive attention for use in fiber lasers for pulse generation due to their unique nonlinear optical properties. While 2D materials with tunable band gaps hold promise as versatile saturable absorber materials, their L-band (long-band) pulse generation capability remains challenging. Metal phosphorus trichalcogenides (MPX3) have recently attracted the attention of researchers and shown potential for sub-band gap saturable absorption in the L-band due to their high diversity of chemical components and band structural complexity. Herein, high-quality MnPSe3 is synthesized and exhibits broad-band linear and nonlinear absorption with the modulation depth and saturation intensity of 5.4% and 0.295 MW/cm2, respectively. Moreover, a stable passive pulse generation in the L-band is demonstrated in a fiber laser. The wavelengths of the passively pulsed laser at different pump powers are recorded, featuring a fixed central wavelength located at around 1602 nm with a maximum output power of 19.54 mW. This research promotes the realization of L-band pulsed lasers based on 2D materials, inspiring further exploration of the unique properties of the MPX3 family.