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In the article the authors discuss light detection and ranging (LiDAR) for automotive applications and the potential roles Si photonics can play in practice. The authors review published research work on Si photonics optical phased array (OPA) and other relevant devices in the past decade with in-depth technical analysis with respect to practical system design considerations. The commercialization status of certain LiDAR technologies is briefly introduced.

In modern manufacturing, cameras are widely used to record the full workflow of assembly line workers, enabling video-based operational analysis and management. However, these recordings are often excessively long, leading to high storage demands and inefficient processing. Existing keyframe extraction methods typically apply uniform strategies across all frames, which are ineffective in detecting subtle movements. To address this, we propose a keyframe extraction method tailored for assembly line videos, combining optical flow estimation with ORB-based visual features. Our approach adapts extraction strategies to actions with different motion amplitudes. Each video frame is first encoded into a feature vector using the ORB algorithm and a bag-of-visual-words model. Optical flow is then calculated using the DIS algorithm, allowing frames to be categorized by motion intensity. Adjacent frames within the same category are grouped, and the appropriate number of clusters, k, is determined based on the group’s characteristics. Keyframes are finally selected via k-means++ clustering within each group. The experimental results show that our method achieves a recall rate of 85.2%, with over 90% recall for actions involving minimal movement. Moreover, the method processes an average of 274 frames per second. These results highlight the method’s effectiveness in identifying subtle actions, reducing redundant content, and delivering high accuracy with efficient performance.

The land cover changes by urbanization have significantly amplified ecological risk (ER). While ecological network (EN) is increasingly adopted as a spatial planning tool for ecosystem restoration, critical spatial and temporal mismatches between EN configurations and evolving ER patterns remain underexplored, leading to suboptimal conservation strategies. Taking the China’s Pearl River Delta (PRD) as an example from 2000 to 2020, this study constructed a comprehensive analysis method combining EN dynamics and ER evolution based on the circuit theory, spatial autocorrelation analysis, and hierarchical mapping. The results showed that: (1) A 116.38% expansion in high-ER zones (2000–2020) paralleled the 4.48% decrease of ecological sources and increased flow resistance in ecological corridors, destabilizing the EN’s structural integrity. (2) Strong negative correlations (Moran’s I = -0.6, p  < 0.01) emerged between EN hotspots (100–150 km urban periphery) and ER clusters (50 km urban core), indicating concentric ER-EN segregation. (3) Single-scale EN planning only addressed localized ER hotspots, disproportionately affecting vulnerable peri-urban zones - a critical environmental justice gap. These results provided insights into the adaptive management of EN within the context of PRD, and potentially offered references for the similar rapidly urbanized megaregions.

Narrow-linewidth semiconductor lasers have become indispensable devices in high-precision measurement and detection. Among various available technologies, self-injection locking plays a crucial role due to its significant ability to reduce linewidth and enhance coherence. Here, we demonstrate a hybrid feedback narrow-linewidth laser based on fixed external cavity feedback combined with self-injection locking feedback. The laser consists of a semiconductor gain chip, fiber Bragg grating, and micro-ring resonator, achieving laser mode selection and linewidth compression. Ultimately, a single longitudinal mode narrow-linewidth laser output with a Lorentzian linewidth of 149 Hz and a side-mode suppression ratio of 65 dB was obtained. The demonstrated laser can be applied in applications such as coherent optical communication and high-precision coherent detection.

Water vapor inevitably existed in most purification and industrial processes which greatly influenced the efficiency. To understand the adsorption behavior of water at molecular level was desirable to elucidate the experimental observations. The work herein addressed the water adsorption on lignite-based activated carbon with consideration of two structural factors: surface oxidation and pore size. The results revealed that graphitic carbon was energetic unfavorable to water that the adsorption amount was less, and water molecules preferentially adsorbed near the defects in the carbon surface. The introduction of carbonyl functionalities changed the hydrophilic property of carbon which greatly increased the adsorption capacity. Water molecules firstly bounded to the functional groups with the separation distance of 2.77–3.11 Å, and small clusters merged with their neighbors to form larger clusters. The average distance of water mass centers was about 2.93–3.13 Å. The pore size distribution had less effect on the adsorption amount of water molecules; however, it significantly limited the size of cluster at higher relatively pressure (p/p 0  = 0.7–0.9) in largely oxidized models (O atomic% = 12%). The largest cluster was consisted of 24–28 and 38–41 water molecules in microporous and micro-/mesoporous model, respectively.

LiDAR has attracted increasing attention because of its strong anti-interference ability and high resolution. Traditional LiDAR systems rely on discrete components and face the challenges of high cost, large volume, and complex construction. Photonic integration technology can solve these problems and achieve high integration, compact dimension, and low-cost on-chip LiDAR solutions. A solid-state frequency-modulated continuous-wave LiDAR based on a silicon photonic chip is proposed and demonstrated. Two sets of optical phased array antennas are integrated on an optical chip to form a transmitter–receiver interleaved coaxial all-solid-state coherent optical system which provides high power efficiency, in principle, compared with a coaxial optical system using a 2 × 2 beam splitter. The solid-state scanning on the chip is realized by optical phased array without a mechanical structure. A 32-channel transmitter–receiver interleaved coaxial all-solid-state FMCW LiDAR chip design is demonstrated. The measured beam width is 0.4° × 0.8°, and the grating lobe suppression ratio is 6 dB. Preliminary FMCW ranging of multiple targets scanned by OPA was performed. The photonic integrated chip is fabricated on a CMOS-compatible silicon photonics platform, providing a steady path to the commercialization of low-cost on-chip solid-state FMCW LiDAR.

Fluid and crystallized intelligence are acknowledged as distinct facets of cognitive ability during brain development, but the specific neural substrates and molecular mechanisms underlying them remain unclear. This study used a sample comprising 7471 young adolescents (mean age 9.87 ± 0.62 years) from the ABCD cohort to elucidate the differential neural correlates of fluid and crystallized intelligence. Our findings indicated that micro-level brain MRI phenotypes such as water diffusivity were closely associated with fluid intelligence, whereas macro-level brain MRI phenotypes such as gray matter cortical thickness were indicative of crystallized intelligence. We further investigated the molecular mechanisms underlying fluid and crystallized intelligence by correlating the characteristic MRI markers with spatial transcriptome profiles and PET imaging. Results showed that fluid intelligence had significant associations with serotonin and glutamate system, while crystallized intelligence was related to serotonin, dopamine and acetylcholine system. Furthermore, we examined the impacts of lifestyle factors on these two forms of intelligence and how the molecular pathways mediated these impacts. Our investigation suggested that physical activities, screen use and sleep duration influenced fluid intelligence mainly through mGlu5 receptors and crystallized intelligence through 5HT1a and D2 receptors. In conclusion, these findings illustrated a distinct neural basis between fluid and crystallized intelligence from the perspectives of neuroimaging, neurotransmitters, and lifestyles in young adolescents.

As a significant type of traumatic brain injury (TBI), blast-induced traumatic brain injury (bTBI) frequently results in severe neurological and psychological impairments. Due to its unique mechanistic and clinical features, bTBI presents diagnostic and therapeutic challenges compared to other TBI forms. The hippocampus, an important site for secondary injury of bTBI, serves as a key niche for neural regeneration and repair post-injury, and is closely associated with the neurological outcomes of bTBI patients. Nonetheless, the pathophysiological alterations of hippocampus underpinning bTBI remain enigmatic, and a corresponding transcriptomic dataset for research reference is yet to be established. In this investigation, the single-nucleus RNA sequencing (snRNA-seq) technique was employed to sequence individual hippocampal nuclei of mice from bTBI and sham group. Upon stringent quality control, gene expression data from 17,278 nuclei were obtained, with the dataset’s reliability substantiated through various analytical methods. This dataset holds considerable potential for exploring secondary hippocampal injury and neurogenesis mechanisms following bTBI, with important reference value for the identification of specific diagnostic and therapeutic targets for bTBI.

We report a novel 2 × 2 broadband 3 dB coupler based on fast adiabatic mode evolution with a compact footprint and large bandwidth. The working principle of the coupler is based on the rapid adiabatic evolution of local eigenmodes of fishbone-like grating waveguides. Different from a traditional adiabatic coupling method realized by the slow change of the cross-section size of a strip waveguide, a fishbone waveguide allows faster adiabatic transition with proper structure and segment designs. The presented 3 dB coupler achieves a bandwidth range of 168 nm with an imbalance of no greater than ±0.1 dB only for a 9 μm coupling region which significantly improves existing adiabatic broadband couplers.

The efficacy of fosfomycin is increasingly challenged by emerging resistance mechanisms, primarily involving fosfomycin-modifying enzymes and target (MurA) alterations. This study aimed to elucidate the novel mechanism underlying fosfomycin resistance in fosfomycin-resistant Staphylococcus haemolyticus (FRSH) strains. Whole-genome sequencing and bioinformatic analysis identified a novel fosfomycin-modifying enzyme, designated FosS, and new mutations (D290H/G359S) on MurA. Cloning experiments further demonstrated that the expression of fosS increased the minimum inhibitory concentration of fosfomycin 32-fold in S. aureus RN4220, whereas MurA mutations induced a 4-fold increase in minimum inhibitory concentration. Phylogenomic analysis revealed that fosS-positive S. haemolyticus (FPSH) is globally distributed, forming a distinct lineage across swine-derived samples from South Korea, South Africa, and China. Moreover, mobile genetic element ISEnfa4, which facilitated horizontal transfer of cfr, was detected downstream of fosS. Notably, various antimicrobial resistance genes (ARGs) were also detected in FPSH. Although fosfomycin was forbidden in food animals in China, the fitness advantages can be conferred by the other ARGs under antimicrobial selective pressure and may facilitate the transmission of FPSH. Overall, this study is the first to report a novel fosfomycin resistance gene and new MurA variants in FRSH. The ISEnfa4 was downstream of fosS and underscored potential mobilization risks. These findings provided a new perspective on One Health to control fosfomycin resistance transmission.