Three-dimensional laser micromachining system with integrated sub-100†nm resolution in-situ measurement.

In this study, a three-dimensional (3D) laser micromachining system with an integrated sub-100 nm resolution in-situ measurement system was proposed. The system used the same femtosecond laser source for in-situ measurement and machining, avoiding errors between the measurement and the machining positions. It could measure the profile of surfaces with an inclination angle of less than 10°, and the measurement resolution was greater than 100 nm. Consequently, the precise and stable movement of the laser focus could be controlled, enabling highly stable 3D micromachining. The results showed that needed patterns could be machined on continuous surfaces using the proposed system. The proposed machining system is of great significance for broadening the application scenarios of laser machining.

scHybridBERT: integrating gene regulation and cell graph for spatiotemporal dynamics in single-cell clustering.

Graph learning models have received increasing attention in the computational analysis of single-cell RNA sequencing (scRNA-seq) data. Compared with conventional deep neural networks, graph neural networks and language models have exhibited superior performance by extracting graph-structured data from raw gene count matrices. Established deep neural network-based clustering approaches generally focus on temporal expression patterns while ignoring inherent interactions at gene-level as well as cell-level, which could be regarded as spatial dynamics in single-cell data. Both gene-gene and cell-cell interactions are able to boost the performance of cell type detection, under the framework of multi-view modeling. In this study, spatiotemporal embedding and cell graphs are extracted to capture spatial dynamics at the molecular level. In order to enhance the accuracy of cell type detection, this study proposes the scHybridBERT architecture to conduct multi-view modeling of scRNA-seq data using extracted spatiotemporal patterns. In this scHybridBERT method, graph learning models are employed to deal with cell graphs and the Performer model employs spatiotemporal embeddings. Experimental outcomes about benchmark scRNA-seq datasets indicate that the proposed scHybridBERT method is able to enhance the accuracy of single-cell clustering tasks by integrating spatiotemporal embeddings and cell graphs.

Arbitrary fabrication of complex lithium niobate three-dimensional microstructures for second harmonic generation enhancement.

Lithium niobate (LN) crystal plays important roles in future integrated photonics, but it is still a great challenge to efficiently fabricate three-dimensional micro-/nanostructures on it. Here, a femtosecond laser direct writing-assisted liquid back-etching technology (FsLDW-LBE) is proposed to achieve the three-dimensional (3D) microfabrication of lithium niobate (LN) with high surface quality (Ra = 0.422 nm). Various 3D structures, such as snowflakes, graphic arrays, criss-cross arrays, and helix arrays, have been successfully fabricated on the surface of LN crystals. As an example, a microcone array was fabricated on LN crystals, which showed a strong second harmonic signal enhancement with up to 12 times bigger than the flat lithium niobate. The results indicate that the method provides a new approach for the microfabrication of lithium niobate crystals for nonlinear optics.

Single femtosecond pulse writing of a bifocal lens.

In this Letter, a method for the fabrication of bifocal lenses is presented by combining surface ablation and bulk modification in a single laser exposure followed by the wet etching processing step. The intensity of a single femtosecond laser pulse was modulated axially into two foci with a designed computer-generated hologram (CGH). Such pulse simultaneously induced an ablation region on the surface and a modified volume inside the fused silica. After etching in hydrofluoric acid (HF), the two exposed regions evolved into a bifocal lens. The area ratio (diameter) of the two lenses can be flexibly adjusted via control of the pulse energy distribution through the CGH. Besides, bifocal lenses with a center offset as well as convex lenses were obtained by a replication technique. This method simplifies the fabrication of micro-optical elements and opens a highly efficient and simple pathway for complex optical surfaces and integrated imaging systems.

Reconfigurable Microlens Array Enables Tunable Imaging Based on Shape Memory Polymers.

Microlens arrays (MLAs) with a tunable imaging ability are core components of advanced micro-optical systems. Nevertheless, tunable MLAs generally suffer from high power consumption, an undeformable rigid body, large and complex systems, or limited focal length tunability. The combination of reconfigurable smart materials with MLAs may lead to distinct advantages including programmable deformation, remote manipulation, and multimodal tunability. However, unlike photopolymers that permit flexible structuring, the fabrication of tunable MLAs and compound eyes (CEs) based on transparent smart materials is still rare. In this work, we report reconfigurable MLAs that enable tunable imaging based on shape memory polymers (SMPs). The smart MLAs with closely packed 200 × 200 microlenses (40.0 µm in size) are fabricated via a combined technology that involves wet etching-assisted femtosecond laser direct writing of MLA templates on quartz, soft lithography for MLA duplication using SMPs, and the mechanical heat setting for programmable reconfiguration. By stretching or squeezing the shape memory MLAs at the transition temperature (80 °C), the size, profiles, and spatial distributions of the microlenses can be programmed. When the MLA is stretched from 0 to 120% (area ratio), the focal length is increased from 116 to 283 µm. As a proof of concept, reconfigurable MLAs and a 3D CE with a tunable field of view (FOV, 160-0°) have been demonstrated in which the thermally triggered shape memory deformation has been employed for tunable imaging. The reconfigurable MLAs and CEs with a tunable focal length and adjustable FOV may hold great promise for developing smart micro-optical systems.

Chimera metasurface for multiterrain invisibility.

Invisibility, a fascinating ability of hiding objects within environments, has attracted broad interest for a long time. However, current invisibility technologies are still restricted to stationary environments and narrow band. Here, we experimentally demonstrate a Chimera metasurface for multiterrain invisibility by synthesizing the natural camouflage traits of various poikilotherms. The metasurface achieves chameleon-like broadband in situ tunable microwave reflection mimicry of realistic water surface, shoal, beach/desert, grassland, and frozen ground from 8 to 12 GHz freely via the circuit-topology-transited mode evolution, while remaining optically transparent as an invisible glass frog. Additionally, the mechanic-driven Chimera metasurface without active electrothermal effect, owning a bearded dragon-like thermal acclimation, can decrease the maximum thermal imaging difference to 3.1 °C in tested realistic terrains, which cannot be recognized by human eyes. Our work transitions camouflage technologies from the constrained scenario to ever-changing terrains and constitutes a big advance toward the new-generation reconfigurable electromagnetics with circuit-topology dynamics.

High-sensitivity fiber optic temperature sensor based on CTFBG-FPI and Vernier effect.

A novel high-sensitivity temperature sensor based on a chirped thin-core fiber Bragg grating Fabry-Perot interferometer (CTFBG-FPI) and the Vernier effect is proposed and demonstrated. With femtosecond laser direct writing technology, two CTFBG-FPIs with different interferometric cavity lengths are inscribed inside a thin-core fiber to form a Vernier effect system. The two FPIs consist of two pairs of CTFBGs with a full width at half maximum (FWHM) of 66.5 nm staggered in parallel. The interferometric cavity lengths of the two FPIs were designed to be 2 mm and 1.98 mm as the reference arm and sensing arm of the sensor, respectively. The temperature sensitivity of this sensor was measured to be -1.084 nm/°C in a range of 40-90°C. This sensor is expected to play a crucial role in precision temperature measurement applications.

Polarization-Orthogonal Nondegenerate Plasmonic Higher-Order Topological States.

Photonic topological states, providing light-manipulation approaches in robust manners, have attracted intense attention. Connecting photonic topological states with far-field degrees of freedom (d.o.f.) has given rise to fruitful phenomena. Recently emerged higher-order topological insulators (HOTIs), hosting boundary states two or more dimensions lower than those of bulk, offer new paradigms to localize or transport light topologically in extended dimensionalities. However, photonic HOTIs have not been related to d.o.f. of radiation fields yet. Here, we report the observation of polarization-orthogonal second-order topological corner states at different frequencies on a designer-plasmonic kagome metasurface in the far field. Such phenomenon stands on two mechanisms, i.e., projecting the far-field polarizations to the intrinsic parity d.o.f. of lattice modes and the parity splitting of the plasmonic corner states in spectra. We theoretically and numerically show that the parity splitting originates from the underlying interorbital coupling. Both near-field and far-field experiments verify the polarization-orthogonal nondegenerate second-order topological corner states. These results promise applications in robust optical single photon emitters and multiplexed photonic devices.

Observation of delocalization transition in topological waveguide arrays with long-range interactions.

Topological edge states are a generic feature of topological insulators, and the long-range interactions, which break certain properties of topological edge states, are always non-negligible in real physical systems. In this Letter, we investigate the influence of next-nearest-neighbor (NNN) interactions on the topological properties of the Su-Schrieffer-Heeger (SSH) model by extracting the survival probabilities at the boundary of the photonic lattices. By introducing a series of integrated photonic waveguide arrays with different strengths of long-range interactions, we experimentally observe delocalization transition of light in SSH lattices with nontrivial phase, which is in good agreement with our theoretical predictions. The results indicate that the NNN interactions can significantly affect the edge states, and that the localization of these states can be absent in topologically nontrivial phase. Our work provides an alternative way to investigate the interplay between long-range interactions and localized states, which may stimulate further interest in topological properties in relevant structures.

Optical near fields for ablation of periodic structures.

The formation mechanism of laser-induced periodic surface structures (LIPSS) has been a key to high-resolution sub-diffraction lithography or high-efficiency large-area nanotexturing. We show the evolution of LIPSS formation from a nanohole seed structure to high-spatial-frequency LIPSS by using a tightly focused and rectangular-shaped laser beam with different shape-polarization orientations. Formation of LIPSS based on light intensity distribution without invoking any long-range electromagnetic modes achieved quantitative match between modeling and experiment. Our results clearly show the entire step-like and deterministic process of LIPSS evolution based on experimental data and numerical simulations, revealing the dominant structural near-field enhancement on the ripple formation. A rectangular-shaped beam with an aspect ratio of 7:3 was used to break the symmetry of a circularly shaped focus. By azimuthally rotating the orientation of the focal spot and the polarization, it is possible to visualize the far-field effect for the initial seed structure formation and the competition between the far and near fields in the subsequent structure evolution.

Arbitrarily rotated optical axis waveguide induced by a trimming line.

Rotated optical axis waveguides can facilitate on-chip arbitrary wave-plate operations, which are crucial tools for developing integrated universal quantum computing algorithms. In this paper, we propose a unique technique based on femtosecond laser direct writing technology to fabricate arbitrarily rotated optical axis waveguides. First, a circular isotropic main waveguide with a non-optical axis was fabricated using a beam shaping method. Thereafter, a trimming line was used to create an artificial stress field near the main waveguide to induce a rotated optical axis. Using this technique, we fabricated high-performance half- and quarter-wave plates. Subsequently, high-fidelity (97.1%) Pauli-X gate operation was demonstrated via quantum process tomography, which constitutes the basis for the full manipulation of on-chip polarization-encoded qubits. In the future, this work is expected to lead to new prospects for polarization-encoded information in photonic integrated circuits.

Nanoscale control of non-reciprocal ripple writing.

Femtosecond laser-induced deep-subwavelength structures have attracted much attention as a nanoscale surface texturization technique. A better understanding of the formation conditions and period control is required. Herein, we report a method of non-reciprocal writing via a tailored optical far-field exposure, where the period of ripples varies along different scanning directions, and achieve a continuous manipulation of the period from 47 to 112 nm (±4 nm) for a 100-nm-thick indium tin oxide (ITO) on glass. A full electromagnetic model was developed to demonstrate the redistributed localized near-field at different stages of ablation with nanoscale precision. It explains the formation of ripples and the asymmetry of the focal spot determines the non-reciprocity of ripple writing. Combined with beam shaping techniques, we achieved non-reciprocal writing (regarding scanning direction) using an aperture-shaped beam. The non-reciprocal writing is expected to open new paths for precise and controllable nanoscale surface texturing.

Three-dimensional on-chip mode converter.

The implementation of transverse mode, polarization, frequency, and other degrees of freedom (d.o.f.s) of photons is an important way to improve the capability of photonic circuits. Here, a three-dimensional (3D) linear polarized (LP) LP11 mode converter was designed and fabricated using a femtosecond laser direct writing (FsLDW) technique. The converter included multi-mode waveguides, symmetric Y splitters, and phase delaying waveguides, which were constructed as different numbers and arrangements of circular cross section waveguides. Finally, the modes (LP11a and LP11b) were generated on-chip with a relatively low insertion loss (IL). The mode converter lays a foundation for on-chip high-order mode generation and conversion between different modes, and will play a significant role in mode coding and decoding of 3D photonic circuits.

Laser-Induced Cavitation-Assisted True 3D Nano-Sculpturing of Hard Materials.

Femtosecond lasers enable flexible and thermal-damage-free ablation of solid materials and are expected to play a critical role in high-precision cutting, drilling, and shaping of electronic chips, display panels, and industrial parts. Although the potential applications are theoretically predicted, true 3D nano-sculpturing of solids such as glasses and crystals, has not yet been demonstrated, owing to the technical challenge of negative cumulative effects of surface changes and debris accumulation on the delivery of laser pulses and subsequent material removal during direct-write ablation. Here, a femtosecond laser-induced cavitation-assisted true 3D nano-sculpturing technique based on the ingenious combination of cavitation dynamics and backside ablation is proposed to achieve stable clear-field point-by-point material removal in real time for precise 3D subtractive fabrication on various difficult-to-process materials. As a result, 3D devices including free-form silica lenses, micro-statue with vivid facial features, and rotatable sapphire micro-mechanical turbine, all with surface roughness less than 10 nm are readily produced. The true 3D processing capability can immediately enable novel structural and functional micro-nano optics and non-silicon micro-electro-mechanical systems based on various hard solids.

Ultralow birefringent glass waveguide fabricated by femtosecond laser direct writing.

Optical waveguides prepared by femtosecond laser direct writing have birefringent properties, which can affect polarization encoding and entanglement on chips. Here, we first propose a shape-stress dual compensation fabrication scheme to decrease birefringence. Ultralow birefringent waveguides (1 × 10-9) were obtained by controlling the cross sectional shape of the main waveguide and adjusting the position of the auxiliary lines. In addition, we prepared polarization-independent directional coupler and demonstrated the evolution of polarization-independent waveguide array with different polarized light. In the future, ultralow birefringent waveguides will be widely applied in polarization encoding and entangled quantum photonic integrated circuits.

Guideline for clinical comprehensive evaluation of Chinese patent medicine (2022 version) / 中国中药杂志

Currently,the research or publications related to the clinical comprehensive evaluation of Chinese patent medicine are increasing,which attracts the broad attention of all circles. According to the completed clinical evaluation report on Chinese patent medicine,there are still practical problems and technical difficulties such as unclear responsibility of the evaluation organization,unclear evaluation subject,miscellaneous evaluation objects,and incomplete and nonstandard evaluation process. In terms of evaluation standards and specifications,there are different types of specifications or guidelines with different emphases issued by different academic groups or relevant institutions. The professional guideline is required to guide the standardized and efficient clinical comprehensive evaluation of Chinese patent medicine and further improve the authority and quality of evaluation. In combination with the characteristics of Chinese patent medicine and the latest research achievement at home and abroad,the detailed specifications were formulated from six aspects including design,theme selection,content and index,outcome,application and appraisal,and quality control. The guideline was developed based on the guideline development requirements of China Assoication of Chinese medicine. After several rounds of expert consensus and public consultation,the current version of the guideline has been developed.

Construction of quality evaluation index system of pulmonary rehabilitation for lung cancer patients based on social ecology theory / 中国实用护理杂志

Objective:To construct a quality evaluation index system of pulmonary rehabilitation for lung cancer patients in order to supply reference for evaluation of rehabilitation quality for lung cancer patients.Methods:This research adopted Delphi technique of non-experimental study. A total of 25 experts were invited to participate 2 rounds of letter enquiry from January to April in 2022. Literature retrieval, group discussion and Delphi method were used to establish the evaluation system of pulmonary rehabilitation for patients with lung cancer based on the social ecology theory.Results:The recovery rates of the two rounds of expert correspondence were 84%(21/25) and 100%(21/21), respectively, the expert authority coefficient was 0.824, and the Kendall′s W value was 0.279 and 0.186, respectively, which were statistically significant ( χ2=409.57, 218.23, both P<0.05). The finally formed quality evaluation index system of pulmonary rehabilitation for lung cancer patients based on social ecology theory included 4 first-level indicators, 11 second-level indicators, and 42 third-level indicators. Conclusions:The evaluation system of pulmonary rehabilitation for lung cancer surgery patients constructed in this study has certain scientificity and practicability, and provides a reference for the continuous improvement of the quality of care for lung cancer patients in our country.

Systematic review and Meta-analysis of efficacy and safety of Fengliao Changweikang prescription in treatment of acute gastroenteritis / 中国中药杂志

This study systematically evaluated the clinical efficacy and safety of Fengliao Changweikang prescription for treating acute gastroenteritis(AGE). The databases of CNKI, Wanfang, VIP, SinoMed, Medline, Cochrane Library and two clinical trial registration platforms were retrieved from inception to August 30, 2022, to collect randomized controlled trial(RCT) on Fengliao Changweikang prescription treating AGE. Two researchers independently conducted literature screening, data extraction, and risk of bias assessment according to pre-established inclusion and exclusion criteria. RevMan 5.4.1 was used for data analysis. Finally, 18 RCTs were included, involving 3 489 patients. Meta-analysis showed that compared with conventional western medicine, Fengliao Changweikang prescription improved the relief rate of abdominal pain(RR=1.27, 95%CI[1.17, 1.38],P<0.000 01); Fengliao Changweikang prescription + conventional western medicine increased the cure rate(RR=1.43, 95%CI[1.12, 1.82], P=0.004), shortened the duration of diarrhoea(RR=-1.65, 95%CI[-2.44,-0.86], P<0.000 1), abdominal pain(RR=-1.46, 95%CI[-2.00,-0.92], P<0.000 01), vomiting(RR=-2.16, 95%CI[-2.51,-1.81], P<0.000 01) and fever(RR=-2.61, 95%CI[-4.00,-1.23], P=0.000 2), down-regulated the level of interleukin-8(IL-8)(RR=-1.07, 95%CI[-1.26,-0.88], P<0.000 01), IL-6(RR=-8.24, 95%CI[-8.99,-7.49], P<0.000 01) and hypersensitive C-reactive protein(hs-CRP)(RR=-3.04, 95%CI[-3.40,-2.69], P<0.000 01) and recurrence of AGE(RR=0.20, 95%CI[0.05, 0.90], P<0.04). In conclusion, Fengliao Changweikang prescription was safe in clinical application. It was beneficial to alleviate the clinical symptoms of diarrhea, abdominal pain, vomiting, and fever, and down-regulate the levels of some serum inflammatory factors in AGE patients. However, considering that few high-quality studies have evaluated the efficacy and safety of Fengliao Changweikang prescription in treatment of AGE, further evidence is needed in the future.

Therapeutic effect of ursodeoxycholic acid-berberine supramolecular nanoparticles on ulcerative colitis based on supramolecular system induced by weak bond / 中国中药杂志

Ulcerative colitis(UC) is a recurrent, intractable inflammatory bowel disease. Coptidis Rhizoma and Bovis Calculus, serving as heat-clearing and toxin-removing drugs, have long been used in the treatment of UC. Berberine(BBR) and ursodeoxycholic acid(UDCA), the main active components of Coptidis Rhizoma and Bovis Calculus, respectively, were employed to obtain UDCA-BBR supramolecular nanoparticles by stimulated co-decocting process for enhancing the therapeutic effect on UC. As revealed by the characterization of supramolecular nanoparticles by field emission scanning electron microscopy(FE-SEM) and dynamic light scattering(DLS), the supramolecular nanoparticles were tetrahedral nanoparticles with an average particle size of 180 nm. The molecular structure was described by ultraviolet spectroscopy, fluorescence spectroscopy, infrared spectroscopy, high-resolution mass spectrometry, and hydrogen-nuclear magnetic resonance(H-NMR) spectroscopy. The results showed that the formation of the supramolecular nano-particle was attributed to the mutual electrostatic attraction and hydrophobic interaction between BBR and UDCA. Additionally, supramolecular nanoparticles were also characterized by sustained release and pH sensitivity. The acute UC model was induced by dextran sulfate sodium(DSS) in mice. It was found that supramolecular nanoparticles could effectively improve body mass reduction and colon shortening in mice with UC(P<0.001) and decrease disease activity index(DAI)(P<0.01). There were statistically significant differences between the supramolecular nanoparticles group and the mechanical mixture group(P<0.001, P<0.05). Enzyme-linked immunosorbent assay(ELISA) was used to detect the serum levels of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6), and the results showed that supramolecular nanoparticles could reduce serum TNF-α and IL-6 levels(P<0.001) and exhibited an obvious difference with the mechanical mixture group(P<0.01, P<0.05). Flow cytometry indicated that supramolecular nanoparticles could reduce the recruitment of neutrophils in the lamina propria of the colon(P<0.05), which was significantly different from the mechanical mixture group(P<0.05). These findings suggested that as compared with the mechanical mixture, the supramolecular nanoparticles could effectively improve the symptoms of acute UC in mice. The study provides a new research idea for the poor absorption of small molecules and the unsatisfactory therapeutic effect of traditional Chinese medicine and lays a foundation for the research on the nano-drug delivery system of traditional Chinese medicine.

Systematic review and Meta-analysis of Biling Weitong Granules in treatment of stomach ache disorder / 中国中药杂志

This study aimed to evaluate the efficacy and safety of Biling Weitong Granules in the treatment of stomach ache disorder. Randomized controlled trial(RCT) of Biling Weitong Granules in the treatment of digestive diseases with stomach ache disorder as the primary symptom was retrieved from Chinese and English electronic databases and trial registration platforms from database inception to June 10, 2022. Two investigators conducted literature screening and data extraction according to the screening criteria. The Cochrane risk-of-bias tool(v 2.0) was used to assess the risk of bias in the included studies. Analyses were performed using RevMan 5.4 and R 4.2.2, with summary estimates measured using fixed or random effects models. The primary outcome indicators were the visual analogue scale(VAS) scores and stomach ache disorder symptom scores. The secondary outcome indicators were clinical recovery rate, Helicobacter pylori(Hp) eradication rate, and adverse reaction/events. Twenty-seven RCTs were included with a sample size of 2 902 cases. Meta-analysis showed that compared with conventional western medicine treatments or placebo, Biling Weitong Granules could improve VAS scores(SMD=-1.90, 95%CI[-2.18,-1.61], P<0.000 01), stomach ache disorder symptom scores(SMD=-1.26, 95%CI[-1.71,-0.82], P<0.000 01), the clinical recovery rate(RR=1.85, 95%CI[1.66, 2.08], P<0.000 01), and Hp eradication rate(RR=1.28, 95%CI[1.20, 1.37], P<0.000 01). Safety evaluation revealed that the main adverse events in the Biling Weitong Granules included nausea and vomiting, rash, diarrhea, loss of appetite, and bitter mouth, and no serious adverse events were reported. Egger's test showed no statistical significance, indicating no publication bias. The results showed that Biling Weitong Granules in the treatment of digestive system diseases with stomach ache disorder as the primary symptom could improve the VAS scores and stomach ache disorder symptom scores of patients, relieve stomach ache disorder, and improve the clinical recovery rate and Hp eradication rate, with good safety and no serious adverse reactions. However, the quality of the original studies was low with certain limitations. Future studies should use unified and standardized detection methods and evaluation criteria of outcome indicators, pay attention to the rigor of study design and implementation, and highlight the clinical safety of the medicine to provide more reliable clinical evidence support for clinical application.