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Metafibers, by integrating metasurface at the optical fiber tip, are emerging as the significant optical coupling platforms for nanophotonics and fiber-optic communities. Here, we propose a plasmonic metafiber for converting the fundamental mode to first-order mode in fiber, and as proof of device performance, demonstrate an all-fiber Q-switched cylindrical vector laser using the metafiber. Based on polarization-dependent plasmonic resonance, a polarization-independent mode conversion metasurface is designed theoretically and numerically, fabricated directly on fiber facet, and packaged as an all-fiber component with efficiency up to 21% at 1550-nm band. Using the metafiber in an all-fiber laser, Q-switched azimuthally polarized beam (APB) and radially polarized beam (RPB) are delivered at wavelength of 1548.5 nm with pulse durations from ∼7 to ∼2 μs when pump power increases from 30 to 120 mW. The mode purities of the APB and RPB are 86.5% and 90.7%, respectively. This work outlines a new strategy to integrate metasurfaces into “all-in-fiber” systems and offers a reliable route to construct next-generation laser sources, such as all-fiber ultrafast structured lasers.

Currently, intercalation has become an effective way to modify the fundamental properties of two-dimensional (2D) van der Waals (vdW) materials. Using density functional theory, we systematically investigated the structures and electronic and magnetic properties of bilayer transition metal dichalcogenides (TMDs) intercalated with 3d TM atoms (TM = Sc–Ni), TM@BL_MS2 (M = Mo, V). Our results demonstrate that all the studied TM@BL_MS2s are of high stability, with large binding energies and high diffusion barriers of TM atoms. Interestingly, most TM@BL_MoS2s and TM@BL_VS2s are found to be stable ferromagnets. Among them, TM@BL_MoS2s (TM = Sc, Ti, Fe, Co) are ferromagnetic metals, TM@BL_MoS2 (TM = V, Cr) and TM@BL_VS2 (TM = Sc, V) are ferromagnetic half-metals, and the remaining systems are found to be ferromagnetic semiconductors. Exceptions are found for Ni@BL_MoS2 and Cr@BL_VS2, which are nonmagnetic semiconductors and ferrimagnetic half-metals, respectively. Further investigations reveal that the electromagnetic properties of TM@BL_MoS2 are significantly influenced by the concentration of intercalated TM atoms. Our study demonstrates that TM atom intercalation is an effective approach for manipulating the electromagnetic properties of two-dimensional materials, facilitating their potential applications in spintronic devices. [ABSTRACT FROM AUTHOR]

Titanium alloy and stainless steel implants have been widely applied in orthopedics. However, harmful ions released from implant corrosion caused by human body fluids and bacterial infections may inhibit patients' recovery. In this work, a polytetrafluoroethylene-silver composite coating was prepared by RF unbalanced magnetron sputtering to improve the bacterial and corrosion resistance of the SS316L. The removal rates of the composite coatings for Escherichia coli and Staphylococcus aureus reached 97.27% and 99.99%, respectively. The contact angle of 131.5° and fluorescence staining experiments show that the composite coating has an antiadhesive effect on bacteria and less cytotoxicity against osteoblasts. The corrosion voltage of the composite coating was much higher than that of the control SS316L substrate, and the corrosion current density was reduced to 1/3, implying the enhancement of the corrosion resistance of the SS316L substrate. [ABSTRACT FROM AUTHOR]

Objective To evaluate the necessity and safety of performing endoscopic retrograde cholangiopancreatography (ERCP) during the pandemic of Coronavirus Disease-2019 (COVID-19) and to share our experience. Methods Clinical data from 174 patients who underwent ERCP procedures in department of surgery and department of emergency Ruijin Hospital, during the period from 17 January 2020 to 19 May 2020 as study group were analyzed retrospectively. All procedures were carried out under strict protective measures. Data from 230 patients who received ERCP during the same period last year were analyzed as control group. The medical records of patients were compared between two groups inclu-ding clinical characteristics, indications, ERCP procedure and duration, complications and hospital stay. Results The cases with biliary and pancreatic malignant obstruction in study group (52, 29.9%) increased significantly compared with those in control group (41, 17.8%) (P=0.004), while the patients of scheduled second ERCP significantly decreased [2(1.1%) vs. 33(14.3%), P

Lead selenide (PbSe) is a new emerging semiconductor with layer-dependent bandgap that has attracted much interest due to its high infrared response and good environmental stability. We have prepared large-scale PbSe films with the area of 7 cm2 and thickness of 25 nm based on physical vapor deposition approach at 160°C. The PbSe films exhibit saturable absorption property at 1.55 μm and a polarization-sensitive saturable absorber is obtained by growing PbSe on D-shaped fiber. Single-pulse with the duration of 490 fs is generated at the pump of 12 mW and the mode-locking operation is maintained at the pump of 1500 mW, indicating the high damage threshold of the D-shaped fiber based saturable absorber. Two polarization-insensitive saturable absorbers are achieved by depositing PbSe on fiber facet and polyvinyl alcohol film, respectively. For fiber facet (polyvinyl alcohol film) based saturable absorber, the repetition rate of Q-switched pulses increases from 8.6 (16.3) kHz to 45.4 (59.2) kHz while the duration decreases from 7.92 (12) μs to 2.06 (3.12) μs by tuning the pump from 15 mW to 90 (60) mW. Such large-scale PbSe films possess features of low cost and high modulation ability, and can find important applications in infrared optical modulators and detectors.

In this paper, we completely determine the irreducible characters of the four families of Suzuki p -groups. [ABSTRACT FROM AUTHOR]

Coupling between modes is crucial for generating coherent structures and spatiotemporal chaos in optical systems. In an ultrafast fiber laser with birefringence, the stable pulse is viewed as a vector soliton (VS) with two orthogonal modes nonlinearly coupled through the Kerr effect and gain/loss. However, the dynamics of a VS in the presence of linear coupling is unperceived despite linear coupling playing a significant role in various optical systems. Here, it is shown that a local linear coupling between polarization modes in lasers facilitates brand‐new nonlinear states, including stationary, breathing, and chaotic VSs. The observed solitary states can be regarded as emergent phenomena when two particles (polarization modes) in a system have a simple interaction (linear coupling), which are ubiquitous in biology, chemistry, and complex systems. It is found that linear coupling is essential for sustaining the internal balance between two modes within the VS. Chaotic dynamics of VS emerge under weak linear coupling, while the two modes lose trapping due to the birefringence in the absence of linear coupling. This work can offer new insight into the two‐mode nonlinear system and inspire research interests in the intelligent manipulation of ultrashort pulse lasers. [ABSTRACT FROM AUTHOR]

This paper proposes a design method for a channel-type sheep dynamic weighing system to address the current problems encountered by pastoralists at home and abroad, such as time-consuming sheep weighing, difficulties with data collection, and management of the stress response in sheep. The complete system includes a hardware structure, dynamic characteristics, and a Kalman-aggregate empirical modal decomposition algorithm (Kalman-EEMD algorithm) model for dynamic data processing. The noise suppression effects of the Kalman filter, the empirical modal decomposition (EMD), and the ensemble empirical modal decomposition (EEMD) algorithms are discussed for practical applications. Field tests showed that the Kalman-EEMD algorithm model has the advantages of high accuracy, efficiency, and reliability. The maximum error between the actual weight of the goats and the measured value in the experiments was 1.0%, with an average error as low as 0.40% and a maximum pass time of 2 s for a single goat. This meets the needs for weighing accuracy and goat flock weighing rates. [ABSTRACT FROM AUTHOR]

Currently, no suitable clinical drugs are available for patients with neurodegenerative diseases complicated by depression. Based on a fusion technique to create effective multi–target–directed ligands (MTDLs), we synthesized a series of (R)–N–(benzo[d]thiazol–2–yl)–2–(1–phenyl–3,4–dihydroisoquinolin–2(1H)–yl) acetamides with substituted benzothiazoles and (S)–1–phenyl–1,2,3,4–tetrahydroisoquinoline. All compounds were tested for their inhibitory potency against monoamine oxidase (MAO) and cholinesterase (ChE) by in vitro enzyme activity assays, and further tested for their specific inhibitory potency against monoamine oxidase B (MAO–B) and butyrylcholinesterase (BuChE). Among them, six compounds (4b–4d, 4f, 4g and 4i) displayed excellent activity. The classical antidepressant forced swim test (FST) was used to verify the in vitro results, revealing that six compounds reduced the immobility time significantly, especially compound 4g. The cytotoxicity of the compounds was assessed by the MTT method and Acridine Orange (AO) staining, with cell viability found to be above 90% at effective compound concentrations, and not toxic to L929 cells reversibility, kinetics and molecular docking studies were also performed using compound 4g, which showed the highest MAO–B and BuChE inhibitory activities. The results of these studies showed that compound 4g binds to the primary interaction sites of both enzymes and has good blood–brain barrier (BBB) penetration. This study provides new strategies for future research on neurodegenerative diseases complicated by depression. [ABSTRACT FROM AUTHOR]

Superior performance of ctDNA by methylation could be due to two reasons: First, ctDNA detection by methylation is only cell-type specific and independent from the individualized mutation profile of each tumour, helping to normalize tumour-specific signal and to "rescue" the detective power for tumours without canonical hotspot or targetable mutations. Tumour recurrence was found in 27.3% (3/11) of patients who are methylation-positive but somatic-mutation-negative with a median RFS of 384 days (95% CI: 356-Inf), or 62.5% (10/16) of patients who are double-positive for somatic mutation as well as DNAm, with a median RFS of 242 days (95% CI: 77-Inf.). Overall, when considering both tumour-derived and tumour-associated, immune-related signals, DNAm was positive in 78.1% (50/64) of samples, whereas cfDNA mutation was positive in 50.0% (32/64) of samples. (B) Somatic hotspot mutation cascade plot in post-surgery blood. gl Mean frequency of CRC-specific DNAm haplotypes, or the mean VAF of tumour-specific somatic mutation (including structural variation) (Figure 2B), were independently used to derive tumour fraction (TF) in cfDNA. [Extracted from the article]

Purpose: To assess the impact of enhanced recovery after surgery (ERAS) protocols in laparoscopic radical nephrectomy (LRN). Methods: The clinical data of 89 patients underwent LRN in Zhongnan Hospital of Wuhan University from February 2019 to September 2021 were collected (40 in the ERAS group and 49 in the pre-ERAS group). The clinical characteristics, prognosis, and length of hospital stay (LOS) were compared between the two groups using t test, Mann-Whitney test, and chi-square test. Results: Total LOS and postoperative LOS were significantly shorter in ERAS group than in pre-ERAS group [15.0 (13.5-19.5) vs. 12.0 (10.0-14.0), P < 0.001; 8.0 (7.0-10.0) vs. 7.0 (5.0-8.8), P = 0.001]. Compared with the pre-ERAS group, the hospitalization expenses of the ERAS group were also lower (P = 0.023). In addition, the incidence of postoperative complications in the ERAS group also decreased (P = 0.054). Conclusions: ERAS protocol in LRN could help accelerate the recovery of patients and is worthy of clinical promotion. [ABSTRACT FROM AUTHOR]

We demonstrate a hybrid-structure fiber laser composed of single-mode fiber (SMF) and four-mode fiber (FMF), capable of delivering stable near-chirp-free soliton with the bandwidth of 75 pm. Ascribed to the spectral-domain intermodal interference, the SMF-FMF cavity serves not only as a ring resonator but also as an intrinsic spectral filter. The wavelength of the narrowband soliton is tunable within 10 nm by a polarization controller. Simulation results validate the experimental observations, revealing that the filtering effect simultaneously balances the self-phase modulation induced spectral broadening and saturable absorption induced temporal compression. The narrowband fiber laser is attractive for spectroscopy, quantum optics, and material processing, and offers a promising platform to study the evolution dynamics of few-mode solitons. [ABSTRACT FROM AUTHOR]

Lead selenide (PbSe) is a new emerging semiconductor with layer-dependent bandgap that has attracted much interest due to its high infrared response and good environmental stability. We have prepared large-scale PbSe films with the area of 7 cm2 and thickness of 25 nm based on physical vapor deposition approach at 160°C. The PbSe films exhibit saturable absorption property at 1.55 μm and a polarization-sensitive saturable absorber is obtained by growing PbSe on D-shaped fiber. Single-pulse with the duration of 490 fs is generated at the pump of 12 mW and the mode-locking operation is maintained at the pump of 1500 mW, indicating the high damage threshold of the D-shaped fiber based saturable absorber. Two polarization-insensitive saturable absorbers are achieved by depositing PbSe on fiber facet and polyvinyl alcohol film, respectively. For fiber facet (polyvinyl alcohol film) based saturable absorber, the repetition rate of Q-switched pulses increases from 8.6 (16.3) kHz to 45.4 (59.2) kHz while the duration decreases from 7.92 (12) μs to 2.06 (3.12) μs by tuning the pump from 15 mW to 90 (60) mW. Such large-scale PbSe films possess features of low cost and high modulation ability, and can find important applications in infrared optical modulators and detectors. [ABSTRACT FROM AUTHOR]

High-order mode fiber lasers are gathering the rising attentions from fundamental researches to practical applications due to their distinctive spatial and temporal properties. Here, we demonstrate a carbon nanotube mode-locked two-mode fiber laser and investigate the formation and evolution process of the soliton based on the time-stretch dispersive Fourier transform method. Stable single pulse and bound-state pulses are observed at pump powers of 32.0 and 41.3 mW, respectively. Attributing to the coexistence of fundamental mode and first group high-order modes, the optical spectrum exhibits slight intensity modulations and the autocorrelation trace shows additional small side lobes. Similar to that of single-mode fiber lasers, the buildup process of soliton includes the relaxation oscillation, beating behavior, and stable mode-locking state. However, owing to the interplay between two transverse modes in the two-mode fiber laser, the duration and fluctuation intensity of the relaxation oscillation are much larger than that of single-mode fiber lasers. [ABSTRACT FROM AUTHOR]

In this paper, we consider regular automorphism groups of graphs in the RT2 family and the Davis‐Xiang family and amorphic abelian Cayley schemes from these graphs. We derive general results on the existence of non‐abelian regular automorphism groups from abelian regular automorphism groups and apply them to the RT2 family and Davis‐Xiang family and their amorphic abelian Cayley schemes to produce amorphic non‐abelian Cayley schemes. [ABSTRACT FROM AUTHOR]

Optical vortices, characterized by helical phase fronts, are usually generated outside the laser cavity using passive modulation methods. Here, we demonstrate an all-fiber laser to directly deliver mode-locked and continuous-wave vortex beams based on modulation of transverse modes in the two mode fiber. The mode couplers and reflectors for three schemes are long period fiber grating (LPFG) and fiber mirror, fiber taper and fiber Bragg grating, and LPFG and fiber Bragg grating, respectively. The laser is switchable between ±1 order vortex operations by tuning the intracavity polarization controller, and the optical vortex can directly work as an optical tweezer to manipulate rhenium diselenide nanosheets. The pulse duration at the mode-locked state is tunable from subpicoseconds to several picoseconds by spectral filters, and the maximum output power at the continuous-wave state exceeds 35 mW. The cost-effective all-fiber vortex laser is quite attractive for research of micromanipulation, spatiotemporal soliton, and optical communication. [ABSTRACT FROM AUTHOR]

We propose three mode converters based on coupling of the fundamental mode and the first group higher-order modes in fiber tapers, angled fiber facets, and transversely dislocated fibers, respectively. The insertion loss and coupling efficiency of the fiber tapers are 0.541 dB and 10.6% respectively, which are much better than those of the angled fiber facets (2.4 dB and 2.9%) or the transversely dislocated fibers (1.2 dB and 5.6%). Cylindrical vector beams are delivered from an erbium-doped fiber laser after separately incorporating the mode converters into the cavity. The output spectra of three lasers are located at 1548.7 nm with the same 3-dB bandwidth of 0.03 nm, and spatial distributions are switchable between radially and azimuthally polarized states by adjusting the incident polarization state of the fundamental mode. The linear-cavity all-fiber lasers are capable of generating flexible and cost-effective cylindrical vector beams, which are quite attractive for fiber-based sensing and communications. [ABSTRACT FROM AUTHOR]

Abstract: Apolipoprotein B mRNA-editing catalytic polypeptide-like 3G (APOBEC3G, or A3G) and related cytidine deaminases such as apolipoprotein B mRNA-editing catalytic polypeptide-like 3F (APOBEC3F, or A3F) are potent inhibitors of retroviruses. Formation of infectious human immunodeficiency virus (HIV)-1 requires suppression of multiple cytidine deaminases by Vif. HIV-1 Vif suppresses various APOBEC3 proteins through a common mechanism by recruiting Cullin5, ElonginB, and ElonginC E3 ubiquitin ligase to induce target protein polyubiquitination and proteasome-mediated degradation. Domains in Vif that mediate APOBEC3 recognition have not been fully characterized. In the present study, we identified a VxIPLx4–5LxΦx2YWxL motif in HIV-1 Vif, which is required for efficient interaction between Vif and A3G, Vif-mediated A3G degradation and virion exclusion, and functional suppression of the A3G antiviral activity. Amino acids 52 to 72 of HIV-1 Vif (including the VxIPLx4–5LxΦx2YWxL motif) alone could mediate interaction with A3G, and this interaction was abolished by mutations of two hydrophobic amino acids in this region. We have also observed that a Vif mutant was ineffective against A3G, yet it retained the ability to interact with Cullin5–E3 ubiquitin complex and A3G, suggesting that interaction with A3G is necessary but not sufficient to inhibit its antiviral function. Unlike the previously identified motif of HIV-1 Vif amino acids 40 to 44, which is only important for A3G suppression, the VxIPLx4–5LxΦx2YWxL motif is also required for efficient A3F interaction and suppression. On the other hand, another motif, TGERxW, of HIV-1 Vif amino acids 74 to 79 was found to be mainly important for A3F interaction and inhibition. Both the VxIPLx4–5LxΦx2YWxL and TGERxW motifs are highly conserved among HIV-1, HIV-2, and various simian immunodeficiency virus Vif proteins. Our data suggest that primate lentiviral Vif molecules recognize their autologous APOBEC3 proteins through conserved structural features that represent attractive targets for the development of novel inhibitors. [Copyright &y& Elsevier]

The retinoblastoma gene ( RB1 ) has been implicated as a tumor suppressor in multiple myeloma (MM), yet its role remains unclear because in the majority of cases with 13q14 deletions, un-mutated RB1 remains expressed from the retained allele. To explore the role of Rb1 in MM, we examined the functional consequences of single- and double-copy Rb1 loss in germinal center B cells, the cells of origin of MM. We generated mice without Rb1 function in germinal center B cells by crossing Rb1 Flox/Flox with C-γ-1-Cre (Cγ1) mice expressing the Cre recombinase in class-switched B cells in a p107 −/− background to prevent p107 from compensating for Rb1 loss ( Cγ1-Rb1 F/F -p107 −/− ). All mice developed normally, but B cells with two copies of Rb1 deleted ( Cγ1-Rb1 F/F -p107 −/− ) exhibited increased proliferation and cell death compared with Cγ1-Rb1 +/+ -p107 −/− controls ex vivo. In vivo, Cγ1-Rb1 F/F -p107 −/− mice had a lower percentage of splenic B220+ cells and reduced numbers of bone marrow antigen-specific secreting cells compared with control mice. Our data indicate that Rb1 loss induces both cell proliferation and death in germinal center B cells. Because no B-cell malignancies developed after 1 year of observation, our data also suggest that Rb1 loss is not sufficient to transform post-germinal center B cells and that additional, specific mutations are likely required to cooperate with Rb1 loss to induce malignant transformation. [ABSTRACT FROM AUTHOR]

• The FE model of the propeller-shaft system is established, whose accuracy is validated through the experiments. • The underwater sound radiation characteristics of the vessel under different directions excitation are studied, including axial excitation, transverse and vertical ones. We found that the natural modes of the propulsion system, especially the bending mode of the propeller, play a key role in the vibro-acoustic responses. • The excitation from the propeller blade is found to be amplified by the propulsion system, and we found that, at low-frequency range, this amplification effect is more remarkable when the direction of the excitation is an axial one than the transverse and vertical ones. • The radiated sound power of the hull structure is compared with that of the propeller at low-frequency range, in which the flow-induced noise is taken into account. We found that although the sound power portion radiated directly from the propeller structure is not so remarkable as that of the hull itself, the magnitude of the flow-induced noise is significant, especially in transverse- and vertical excitation cases. The radiated noise induced by the unsteady propeller forces is an important part of the vessel's total acoustic radiation. Therefore, understanding the role of propeller-shafting system in force transmission characteristics is necessary investigate the underwater vibro-acoustic responses of a vessel. This study compared the contribution of hull and propeller-shafting system to the radiated sound power under the propeller forces in different directions. First, a finite element/boundary element (FE/BE) model of a hull with relatively detailed substructures was developed to study the system's vibro-acoustic characteristics, in which the pulsating pressure at the propeller blade was transmitted to the hull through the propulsion system. The accuracy of the model was validated by experimental results. Second, finite element/boundary element method (FEM/BEM) was used to study the vibro-acoustic characteristics of the submerged system and the amplification effects of the propeller-shafting system. Finally, the radiated sound power of the propeller and the hull were compared, considering the flow-induced noise generated by the water surrounding the propeller. Results show that while it is reasonable to ignore the sound power generated by the elastic propeller structure, the flow-induced noise still needs to be considered, especially when the forces are applied to the propeller in the transverse and vertical directions. [ABSTRACT FROM AUTHOR]

Metal-metal bonding is crucial in chemistry for advancing our understanding of the fundamental aspects of chemical bonds. Metal-metal bonds based on alkaline-earth (Ae) elements, especially the heavier Ae elements (Ca, Sr, and Ba), are rarely reported due to their high electropositivity. Herein, we report two heteronuclear di-EMFs CaY@ C s (6)-C 82 and CaY@ C 2 v (5)-C 80 , which contain unprecedented single-electron Ca-Y metal-metal bonds. These compounds were characterized by single-crystal X-ray crystallography, electron paramagnetic resonance (EPR) spectroscopy, and DFT calculations. The crystallographic study of CaY@ C s (6)-C 82 shows that Ca and Y are successfully encapsulated into the carbon cage with a Ca-Y distance of 3.691 Å. The CW-EPR study of both CaY@ C s (6)-C 82 and CaY@ C 2 v (5)-C 80 exhibits a doublet, suggesting the presence of an unpaired electron located between Ca and Y. The combined experimental and theoretical results confirm the presence of a Ca-Y single-electron metal-metal bond with substantial covalent interaction, attributed to significant overlap between the 4s4p orbitals of Ca and the 5s5p4d orbitals of Y. Furthermore, pulse EPR spectroscopy was used to investigate the quantum coherence of the electron spin within this bond. The unpaired electron, characterized by its s orbital nature, is effectively protected by the carbon cage, resulting in efficient suppression of both spin-lattice relaxation and decoherence. CaY@ C s (6)-C 82 behaves as an electron spin qubit, displaying a maximum decoherence time of 7.74 μs at 40 K. This study reveals an unprecedented Ae-rare-earth metal-metal bond stabilized by the fullerene cages and elucidates the molecular qubit properties stemming from their unique bonding character, highlighting their potential in quantum information processing applications.

Reprogramming of energy metabolism is one of the most important characteristics of tumors. Bladder cancer (BLCA) cells contain higher levels of cholesterol content compared to normal cells, and acyl-coenzyme A (CoA): cholesterol acyltransferase-1 (ACAT1) plays a crucial role in the esterification of cholesterol. Avasimibe is a drug that has been used in the treatment of atherosclerosis, and it can effectively inhibit ACAT1. We observed that ACAT1 was significantly up-regulated in BLCA and positively correlated with tumor grade. By avasimibe administration, the proliferation and migration ability of BLCA cells were reduced, while the production of ROS was strongly increased, accompanied by the up-regulated expression of ROS metabolism-related proteins SOD2 and catalase. Furthermore, BLCA cell cycle was arrested at the G1 phase, accompanied by the downregulation of cell cycle-related proteins (CCNA1/2, CCND1, CDK2 and CDK4), while the PPARγ was found to be up-regulated at both transcriptional and protein levels after avasimibe treatment. Then we found that the PPARγ antagonist GW9662 could reverse the effect of avasimibe on the cell cycle. Moreover, xenograft and pulmonary metastasis models further demonstrated that avasimibe could inhibit tumor cell growth and metastasis in vivo . Taken together, our results for the first time revealed that avasimibe can inhibit BLCA progression and metastasis, and PPARγ signaling pathway may play a key role in regulation of cell cycle distribution induced by avasimibe., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

We demonstrate a unique pulse-splitting mechanism dominated by the linear coupling between two vector modes in a mode-locked fiber laser using polarization-maintaining fiber. As the linear coupling strength increases, the pulse experiences larger perturbations and manifests as stronger spectral sidebands. Correspondingly, the temporal pedestals possessing a higher intensity become untrapped and eventually evolve into a stable pulse. Such linear coupling-related pulse splitting is ubiquitous both in normal- and anomalous-dispersion regimes, fundamentally differing from that induced by the excessive nonlinear phase shift. Experimental observations fully sustain numerical results and provide a flexible approach to managing the number and energy of vector solitons.

Ultrafast few-mode fiber lasers have received increasing attention from basic research to practical applications due to their unique pulse performance and intriguing nonlinear dynamics. Here, we experimentally and numerically reveal the formation and evolution behaviors of a soliton in a mode-locked fiber laser composed of two-mode and single-mode fibers. The LP 11 pulse walks away from the LP 01 pulse in the two-mode fiber due to modal dispersion and then transforms into an auxiliary LP 01 pulse after entering the single-mode fiber. After re-entering the two-mode fiber, the LP 01 pulse excites the LP 11 pulse via mode coupling; therefore, the LP 11 pulse also consists of dominant and auxiliary pulses. Such a soliton fiber laser converges to an asymptotic steady state with unlocked spatial modes arising from the interplay between the strong modal dispersion and weak mode coupling.

In a nonlinear optical system with birefringence such as fiber lasers, soliton trapping can be achieved when the fast (slow) component experiences blueshift (redshift) at normal dispersion to compensate for polarization-mode dispersion (PMD). In this Letter, we demonstrate an anomalous vector soliton (VS) whose fast (slow) component shifts to the red (blue) sides, which is opposite to traditional soliton trapping. It is found that the repulsion between the two components is induced by net-normal dispersion and PMD, while the attraction is ascribed to linear mode coupling and saturable absorption. The equilibrium of attraction and repulsion permits the self-consistent evolution of VSs circulating in the cavity. Our results indicate that the stability and dynamics of VSs are worth revisiting and studying in-depth, especially in lasers with complex configurations, despite it being a well-known object in nonlinear optics.

Autoimmune polyendocrine syndrome type-1 (APS-1) is a rare inherited monogenic autoimmune disease characterized by the presence of at least two of three following major clinical features: chronic mucocutaneous candidiasis, hypoparathyroidism, and adrenal insufficiency. Mutations in autoimmune regulator (AIRE) gene have been found to contribute to APS-1. In the present study, we reported a 36-years-old male APS-1 patient who presented with hypoparathyroidism and Addison's disease. The proband underwent complete clinical examinations and mutation screening was performed by Sanger sequencing on AIRE gene. A novel homozygous mutation in exon 9 of the AIRE gene (c.1024C>T) was identified. Based on sequencing findings, HEK293T cell-based assays were conducted to analyze the subcellular localization and mutant transcript processing. Our results revealed that p.Q342X mutant localized in nuclear speckles and exerted a dominant-negative effect on wildtype AIRE function. We reported the c.1024C>T mutation of AIRE gene for the first time, which enriched the AIRE mutation database and contributed to further understanding of APS-1., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Qian, Yan, Xuan, Zheng, He and Shen.)

Pulsating solitons are intriguing objects in laser physics and nonlinear science. Recently, emerging works on the pulsating multi-solitons have raised interest in interactions and synchronizations within multiple breathers. However, with their separation of the order of nanoseconds, the evolution and underlying dynamics of multiple pulsating solitons remain uncharted. In this work, we bring initial insights into the pulsating dual-soliton (PDS) with a separation of three orders of magnitude of the pulse duration. Chaotic, synchronous, and asynchronous pulsations are revealed to be controlled by the pump power. Specifically, two solitons can pulsate synchronously in the form of a frozen limit cycle. The asynchronous PDS at a high pump power brings the rotating limit cycle in the phase space. Unveiling the evolutionary dynamics of PDS, this work has potential in all-optical storage, signal encoding, and time division multiplexing communications.

The bound states (BSs) of solitons are found to have intriguing internal dynamics in ultrafast lasers. Here, we explore the binding mechanism and internal motions of asymmetric bound state (ABS) solitons constituted by unequal solitons at short-range with their tails directly overlapped. Experiments and simulations show that the periodic energy flux between two solitons, mediated by their overlapped tails, gives rise to a balanced separation and energy distribution across the ABS. The motion mechanisms of strong and weak solitons are discussed in detail. This work provides insights into the binding mechanism and internal dynamics of BSs.