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The development of digitized humanity information provides a new perspective on data-oriented studies of history. Many previous studies have ignored uncertainty in the exploration of historical figures and events, which has limited the capability of researchers to capture complex processes associated with historical phenomena. We propose a visual reasoning system to support visual reasoning of uncertainty associated with spatio-temporal events of historical figures based on data from the China Biographical Database Project. We build a knowledge graph of entities extracted from a historical database to capture uncertainty generated by missing data and error. The proposed system uses an overview of chronology, a map view, and an interpersonal relation matrix to describe and analyse heterogeneous information of events. The system also includes uncertainty visualization to identify uncertain events with missing or imprecise spatio-temporal information. Results from case studies and expert evaluations suggest that the visual reasoning system is able to quantify and reduce uncertainty generated by the data.

A molecule featuring two distinct cooperatively grown J-aggregates is investigated. Interestingly, when cooling a hot monomer solution, the thermodynamically less stable J

Ultrathin Al2O3 insulating intercalations with different thicknesses and numbers, prepared by atomic layer deposition technology, were introduced into Ba(Zr0.2Ti0.8)O3 (BZT) relaxor ferroelectric films as the dielectric for electrostatic energy storage capacitors. The phase structure, microstructure and electrical properties were investigated in detail. Due to the insertion of insulating layers, the films show less leakage current and enhanced voltage endurance capability when the thickness of single Al2O3 intercalation exceeds a threshold (0.45–0.9 nm). The voltage endurance capability can be more enhanced by increasing the number of Al2O3 intercalations. For energy storage applications, the energy storage density and efficiency obtained from the polarization-electric field loops are significantly improved owing to the suppressed leakage and enhanced voltage endurance ability. The results promote the application of BZT-based films in electrostatic energy storage. It is demonstrated that the introduction of atomic-layer-deposited insulating intercalations with controllable thickness, such as those fabricated by ALD method, is an effective way to improve the electrical performance of devices based on composite materials.

Polycyclic aromatic hydrocarbon (PAH) structures with suitable electron-withdrawing groups are useful building blocks for developing optical and electron-transporting materials. Here, we report the application of a double benzannulation process to the syntheses of PAH diimides with enlarged π-frameworks featuring a central anthracene moiety. The preparations are realized by copper-catalyzed [4+2] cycloaddition of ethynyl-substituted aromatic dicarboximide to 2,5-bis(phenylethynyl)terephthalaldehyde, followed by intramolecular photocyclization or direct arylation via Heck cross coupling. A central symmetric benzo[1,2-k:4,5-k']-bis(fluoranthene)-3,4,12,13-tetracarboxyl diimide (BFDI) is acquired, with the single crystal structure revealing its completely planar polycyclic skeleton. Such a shape-persistent PAH expectedly exhibits a tendency to stack face-to-face and forms J-aggregates. Moreover, BFDI can be difunctionalized site-selectively at the reactive 9 and 10 positions of the anthracene unit and then applied to prepare conjugated polymers. When coupled with 1,4-diketopyrrolo[3,4-c]-pyrrole (DPP) via thiophene and dithiophene linkers, two polymers with significantly broadened absorption bands extended to the near-infrared regime are obtained, evidencing the effective π-conjugative extension ability of BFDI unit.

The burgeoning advances of spatial mode conversion in few-mode fibers emerge as the investigative hotspot in novel structured light manipulation, in that, high-order modes possess a novel fundamental signature of various intensity profiles and unique polarization distributions, especially orbital angular momentum modes carrying with phase singularity and spiral wave front. Thus, control of spatial mode generation becomes a crucial technique especially in fiber optics, which has been exploited to high capacity space division multiplexing. The acousto-optic interactions in few-mode fibers provide a potential solution to tackle the bottleneck of traditional spatial mode conversion devices. Acousto-optic mode conversion controlled by microwave signals brings tremendous new opportunities in spatial mode generation with fast mode tuning and dynamic switching capabilities. Besides, dynamic mode switching induced by acousto-optic effects contributes an energy modulation inside a laser cavity through nonlinear effects of multi-mode interaction, competition, which endows the fiber laser with new functions and leads to the exploration of new physical mechanism. In this review, we present the recent advances of controlling mode switch and generation employing acousto-optic interactions in few-mode fibers, which includes acousto-optic mechanisms, optical field manipulating devices and novel applications of spatial mode control especially in high-order mode fiber lasers.

We experimentally obtain a lower frequency shift based on mode conversion by using a mode-selective coupler (MSC) and an acoustically induced fiber grating (AIFG) for optical heterodyne micro-vibration measurement. Through efficient conversion between LP11 and LP01 core modes in a few-mode fiber, a mode conversion frequency shifter (MCFS) can be achieved and the magnitude of frequency shift is several hundred kHz, which is generally challenging for traditional bulk acousto-optic frequency shifter. Moreover, the signal-to-signal beating interference (SSBI) can be eliminated by using the MCFS without requirement of guard band. The scheme of optical heterodyne micro-vibration measurement based on the MCFS has a high-quality signal-to-noise ratio (SNR) over 85 dB. An all-fiber Bragg grating (FBG) scheme is also designed to improve the measurement sensitivity of heterodyne detection, which has a measurable vibration frequency range of 1 Hz to 300 kHz and minimal detectable amplitude of 0.019 nm. The all-fiber MCFS has the advantages of compactness, easy integration and can be applied directly to satellite ground station and laser feedback tomography.

Two novel A-D-A shaped dimesitylboron endcapped S,N-heteroacenes (DMB-DTP and DMB-BTTP) were designed and synthesized. With the extension of conjugation from DMB-DTP to DMB-BTTP, a serious of chang...

We investigated the cognitive and socioemotional effects of a light painting intervention, which is a new type of creative arts therapy. Participants were 60 university students, 30 of whom were assigned to the light painting (LP) group and attended 5 light painting sessions for 1 hour every other day, and 30 of whom were assigned to the control group and engaged in classroom self-study on the same schedule. Both groups completed a spatial orientation task and the Positive Affect and Negative Affect Schedule before and after the intervention. Compared to the control group, the LP group showed significant improvement in speed of performing the spatial orientation task. Moreover, the LP group reported increases in imagination, creativity, emotional and mental health, and social skills. Our findings provide preliminary empirical evidence supporting the positive effect of LP in some cognitive and socioemotional domains, and indicate that LP could be a promising creative arts therapy intervention for treating psychiatric disorders.

We demonstrate a real-time transverse-mode switching of ultrafast pulse via a cascading mode conversion. The cascading all-fiber mode converter is comprised of a mode-selective coupler (MSC) and an acoustically induced fiber grating (AIFG), which functions as a broadband and controllable beam shaper, and offers a real-time mode switching between LP11 and LP21 modes with $\sim ~190~\mu \text{s}$ switching time. Such a transverse mode-switchable all-fiber laser presents a pulse duration of 1.4 ps and flexible transverse-mode switching. We believe that this compact and robust all-fiber laser source would find promising applications in the field of ultrafast optics and structured light microscope.

The aim of the present study was to explore whether people consider their own voice to be more attractive than others and whether the self‐enhancement bias of one's own voice could be generalised t...

A novel electron acceptor, namely, tetra-phthalimide end-fused bifluorenylidene (3D-imide) was designed and synthesized. In comparison to its framework analogue 12,12'-bidibenzo[b,h]fluorenylidene (BF-3), the electron withdrawing capability and optical absorption were strengthened and enlarged, respectively. Moreover, photoluminescence quenching experiments were carried out, which confirmed 3D-imide could be a good candidate for nonfullene organic photovoltaics. Finally, we gained more insight into its electronic properties through density functional theory calculation.

The United Nations (UN) proposed the Sustainable Development Goals (SDG 17) in 2015, together with The Paris Agreement endorsed by 195 signatories and state parties, to address sustainable development-related issues through ambitious and dynamic actions. The transition of the energy system is at the heart of greenhouse gas (GHGs) mitigation which is required to achieve those goals and the electric sector is the core of energy system of interest while the GHG with the largest contribution to rising temperature is carbon dioxide. However, in addition to being centrally relevant for carbon emissions, the electric sector is also an important water consumer. This study applied a hybrid life cycle assessment (LCA) model with the disaggregated electric sector to investigate the impacts on carbon emission and water consumption of the energy transition in Japan under the Sixth Strategic Energy Plan. The results indicate that the electricity mix under the Nationally Determined Contribution (NDC) scenario can cut 50% of existing carbon emissions while intensifying the water consumption by 36% from the life cycle perspective in which 30% are foreign water footprints. The Kaya identity analysis confirmed this conclusion and explained the impacts of four driving factors (population, economy, electricity intensity, and electricity mix) qualitatively and quantitatively showing that the development of technologies and continuous efforts in energy saving can provide a substantial contribution to sustainable development. The results confirmed that the efforts proposed by Japan’s NDC for emission reduction through an energy transition in the electric sector can meet the expectation of achieving the Paris Agreement goals but will also pose greater challenges to the future global water demand in the energy system and regional water stress.

We propose an all-fiber configuration of tunable bandpass filter (TBPF), consisting of a mode selective coupler (MSC) and an acoustically induced fiber grating (AIFG). Either the MSC or the AIFG can act as high-order mode converters in a few-mode fiber. The working wavelengths of the MSC and the AIFG are chosen to achieve complete conversion cycle between the core-mode linearly polarized (LP01) mode and the LP11 mode. The tunability of the TBPF is achieved by changing the frequency of the radio frequency signal. An all-fiber tunable ring laser based on the TBPF is used to generate a stable continuous-wave laser with 3-dB bandwidth of around 0.8 nm. The tunable wavelength ranges from 1530 to 1580 nm. Furthermore, the TBPF is introduced into the cavity of a mode-locked fiber laser. Wavelength-tunable mode locking pulses are obtained at central wavelengths from 1530 to 1560 nm.

We experimentally demonstrated a scheme of dynamic switching between LP01 and LP11 modes in a Brillouin/Erbium fiber lasers based on acoustically-induced fiber grating and realized tunable-wavelength Brillouin laser output.

This paper mainly studies the application of tunable laser and acoustic grating in TDLAS gas sensoring. The tunable laser is used for wavelength tuning, and the acoustic-vibration grating is used for signal light modulation in the TDLAS system. The ammonia harmonic signal detection at 1512.84 nm is realized. The feasibility of the tunable laser and the acoustic-vibration grating for ammonia detection is verified. The characteristics of the acoustic-vibration grating near 1512 nm are studied.

Fiber lasers operating in on-demand spatial transverse modes have recently gained extensive attention due to their great flexibility in practical applications. Typically, free-form mode converters are widely used to generate flexible transverse modes in solid-state or fiber lasers, which call for a strict calibration and are susceptible to mechanical perturbations [1]. Recently, fiber-based few-mode fiber Bragg grating (FMF-FBG) has been developed and applied to transverse-mode switchable mode-locked all-fiber lasers [2]. However, FMF-FBG usually has a narrow-band mode conversion resulting in picoseconds pulse duration. Moreover, most FMF-FBG based fiber lasers operate at the lowest transverse modes (LP 01 and LP 11 modes).

We propose a dynamic scheme to realize mode-switchable generation of LP11a/b modes and ±1-order orbital angular momentum (OAM) modes simultaneously, which are induced by an acoustically induced fiber grating driven by radio frequency modulation. LP11a/b mode degeneration in a few-mode fiber is induced by the geometric irregularity of optical fibers. A dual-wavelength resonance of mode coupling from LP01 to LP11a/b modes is found based on the combined effects of optical and acoustic birefringence. Within the configuration of continuous-wave intra-cavity laser output, we experimentally demonstrate a fast-switchable generation of LP11a/b modes and optical vortex beams with ±1-order OAM at a switching speed up to 4.3 kHz. This approach has potential applications in mode-division multiplexing, particle manipulation, stimulated emission depletion microscopy, and quantum information science.

Ultrafast high-order mode (HOM) lasers are a relatively new class of ultrafast optics. They play a significant role in the fieldsof scientific research and industrial applications due to the high peak power and unique properties of spatial intensity and polarization distribution. Generation of ultrafast HOM beams in all-fiber systems has become an important research direction. In this paper, all-fiber mode conversion techniques, pulsed HOM laser strategies, and few-mode/multi-mode fiber (FMF/MMF) lasers are reviewed. The main motivation of this review is to highlight recent advances in the field of all-fiber ultrafast HOM lasers, for example, generating different HOM pulses based on fiber mode converters and mode-locking in the FMF/MMF lasers. These results suggest that mode selective coupler can be used as a broad bandwidth mode converter with fast response and HOM can be directly oscillated in the FMF/MMF laser cavity with high stability. In addition, spatiotemporal mode-locking in the FMF/MMF is also involved. It is believed that the development of all-fiber ultrafast HOM lasers will continue to deepen, thus laying a good foundation for future applications.

Temporal and spatial resonant modes are always possessed in physical systems with energy oscillation. In ultrafast fiber lasers, enormous progress has been made toward controlling the interactions of many longitudinal modes, which results in temporally mode-locked pulses. Recently, optical vortex beams have been extensively investigated due to their quantized orbital angular momentum, spatially donut-like intensity, and spiral phase front. In this paper, we have demonstrated the first to our knowledge observation of optical vortex mode switching and their corresponding pulse evolution dynamics in a narrow-linewidth mode-locked fiber laser. The spatial mode switching is achieved by incorporating a dual-resonant acousto-optic mode converter in the vortex mode-locked fiber laser. The vortex mode-switching dynamics have four stages, including quiet-down, relaxation oscillation, quasi mode-locking, and energy recovery prior to the stable mode-locking of another vortex mode. The evolution dynamics of the wavelength shifting during the switching process are observed via the time-stretch dispersion Fourier transform method. The spatial mode competition through optical nonlinearity induces energy fluctuation on the time scale of ultrashort pulses, which plays an essential role in the mode-switching dynamic process. The results have great implications in the study of spatial mode-locking mechanisms and ultrashort laser applications.

we demonstrated an orthogonal mode-switching fiber laser based on an acoustically-induced fiber grating (AIFG), which can convert LP 01 to ${\text{LP}}_{11}^{\text{a}}$ and ${\text{LP}}_{11}^b$ modes by modulating the RF frequency.

Inula japonica belongs to the family Asteraceae, and its flowers have been used as dietary supplements and health tea in China. The study aimed to identify the bioactive components with the antiproliferative property. Ten 1,10-seco-eudesmanolide derivatives, including four new compounds (1-4), were isolated from the flowers of I. japonica. Their structures were established on the basis of the interpretation of spectroscopic data and electronic circular dichroism (ECD) calculations. All of these isolates were evaluated for their antiproliferative activities against MCF-7 and MDA-MB-231 human breast cancer cells. Compound 4 possessed the most potent effects, with the IC50 values of 0.20 ± 0.04 and 6.22 ± 1.30 μM against MCF-7 and MDA-MB-231 cells, respectively. The present investigation indicated that eudesmanolide derivatives from the flowers of I. japonica, especially compound 4, might be used as potential antitumor chemotherapy agent candidates.

A highly selective molecularly imprinted polymer electrochemical sensor for In3+ detection was proposed. In3+ ion was chelated with alizarin red S to form a complex In-ARS. The complex was used as the template molecule to prepare a molecularly imprinted polymer (MIP) based sensor. The selectivity of the sensor was improved significantly due to the three-dimensional specific structure of the complex, and the selective complexation of ligands for metal ions. Moreover, the sensitivity of the proposed sensor was improved by recording the reductive current of ligand in complex. This technique was highly sensitive for quantitative analysis of In3+ in the concentrations ranged from 1×10−8 mol/L to 2.5×10−7 mol/L with a detection limit of 4.7×10−9 mol/L. The proposed sensor has been successfully used in detecting In3+ in real samples.

One new xanthanolide, 4-(2-methybutyryl)-4H-tomentosin (1) was isolated from the whole plant of Carpesium macrocephalum together with nine known sesquiterpenes (2-10), including four eudesmane sesquiterpenes (2, 4, 5, and 10), one guaianolide (3), two xanthanolides (6 and 9) and two carabranolides (7 and 8). Their structures were elucidated on the basis of detailed spectroscopic analyses. All isolates were evaluated for their antifungal activities against the growth, biofilm formation and yeast-hyphal transition in Candida albicans. All compounds lacked the antifungal activity (MIC50>256 μg/ml) except compound 6 with the MIC50 value of 128 μg/ml. However, compounds 3, 5 and 10 strongly inhibited biofilm formation with IC50 values ranging from 15.4 to 38.0 μg/mL, and compounds 1, 3, 4, 6 and 7 inhibited the yeast-to-hyphae morphogenetic transition with the IC50 values between 31.6 and 118.4 μg/mL. The above results indicated that sesquiterpenes from C. macrocephalum may have therapeutic potential for candidiasis as virulence inhibitors.

4-(2-Methylbutyryl)-4H-tomentosin (I), a new xanthanolide from the whole plant of Carpesium macrocephalum, is isolated along with nine known sesquiterpenes.

To detect the expression and distribution of the lung surfactant protein D (surfactant protein D,SP-D ) and IL-16 in nasal mucosa of allergic rhinitis and nasal polyps, and then probe into their significance in the pathology of allergic rhinitis and nasal polyps.Fifteen cases of allergic rhinitis, fifteen cases of nasal polyps and fifteen cases of inferior turbinate mucosa were studied to detect the expression of SP-D and IL-16 by immunohistochemistry method.The expression of SP-D and IL-16 in allergic rhinitis and nasal polyps were dramatically higher in controls (P0.01). There was no remarkable difference in the expression of SP-D and IL-16 between allergic rhinitis and nasal polyps (P0.05).Both normal tissue and diseased tissue express SP-D and IL-16. SP-D is likely to play key roles in the inflammatory reaction process of allergic rhinitis and nasal polyps. IL-16 is an important eosinophil chemokine in the process of allergic rhinitis and nasal polyps,and it can also enhance the local role of eosinophils,thus it can involve in the process of allergic rhinitis and nasal polyps disease.