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In recent years, UAV object tracking has provided technical support across various fields. Most existing work relies on convolutional neural networks (CNNs) or visual transformers. However, CNNs have limited receptive fields, resulting in suboptimal performance, while transformers require substantial computational resources, making training and inference challenging. Mountainous and jungle environments-critical components of the Earth's surface and key scenarios for UAV object tracking-present unique challenges due to steep terrain, dense vegetation, and rapidly changing weather conditions, which complicate UAV tracking. The lack of relevant datasets further reduces tracking accuracy. This article introduces a new tracking framework based on a state-space model called TrackingMamba, which uses a single-stream tracking architecture with Vision Mamba as its backbone. TrackingMamba not only matches transformer-based trackers in global feature extraction and long-range dependence modeling but also maintains computational efficiency with linear growth. Compared to other advanced trackers, TrackingMamba delivers higher accuracy with a simpler model framework, fewer parameters, and reduced FLOPs. Specifically, on the UAV123 benchmark, TrackingMamba outperforms the baseline model OSTtrack-256, improving AUC by 2.59% and Precision by 4.42%, while reducing parameters by 95.52% and FLOPs by 95.02%. The article also evaluates the performance and shortcomings of TrackingMamba and other advanced trackers in the complex and critical context of jungle environments, and it explores potential future research directions in UAV jungle object tracking.

Wide-range multiscale object detection for multispectral scene perception from a drone perspective is challenging. Previous RGB-T perception methods directly use backbone pretrained on RGB for thermal infrared feature extraction, leading to unexpected domain shift. We propose a novel multimodal feature-guided masked reconstruction pretraining method, named M2FP, aimed at learning transferable representations for drone-based RGB-T environmental perception tasks without domain bias. This article includes two key innovations as follows. 1) We design a cross-modal feature interaction module in M2FP, which encourages modality-specific backbones to actively learn cross-modal feature representations and avoid modality bias issues. 2) We design a global-aware feature interaction and fusion module suitable for various downstream tasks, which enhances the model's environmental perception from a global perspective in wide-range drone-based scenes. We fine-tune M2FP on the drone-based object detection dataset (DroneVehicle) and semantic segmentation dataset (Kust4K). On these two tasks, compared to the second-best methods, M2FP achieves state-of-the-art performance, with an improvement of 1.8% in mean average precision and 0.9% in mean intersection over union, respectively.

Numerous scholars have investigated the determinants of university innovation efficiency. However, the internal governance aspects of universities and their interactions with the external environment are frequently neglected. Therefore, this study, grounded in the framework of embeddedness theory, employed the Stochastic Frontier Analysis method to empirically analyze innovation efficiency in Chinese universities. The results indicated that competitive threats significantly improved university innovation efficiency, whereas bureaucracy and international openness exhibited adverse effects, which were alleviated in regions with greater marketization.

To explore the effect of 1-methylcyclopropene (1−MCP) on the storage quality of edible roses, flowers of the edible rose variety ‘Dianhong’ were used as materials to study the effect of post-harvest 1−MCP fumigation (concentration of 30 μL/L). The measures included respiration intensity, water loss rate, antioxidant-related substance content (soluble sugar, crude fibre, AsA, anthocyanin, total phenols and MDA), enzyme activity (SOD, CAT, APX, PAL and PPO) and petal appearance quality in different storage periods, which could provide a theoretical reference for research and development on storage and preservation technology for edible rose petals. The results showed that, compared with the control, 1−MCP treatment reduced the initial respiration intensity of petals by more than 80%, slowed the water loss rate, increased the crude fibre content and effectively maintained the contents of soluble sugars, AsA, anthocyanins and total phenols. For the petals in the treatment group at the end of storage, the rate of water loss was 3.73%, the content of soluble sugar was only 17% (62.27 μg/g)—lower than that of fresh petals—and the content of AsA (0.33 mg/g) was the same as that of pre-storage (0.34 mg/g). The contents of total phenols and anthocyanins were 30.60% and 11.63% higher than those of the control group, respectively. In addition, 1−MCP treatment increased the activity of SOD, CAT, APX and PAL and inhibited the activity of PPO. The MDA content at the end of storage was 14.36% lower than that of the control, which reduced the rate of membrane lipid peroxidation. Correlation analysis showed that sensory quality of petals in the 1−MCP treatment group was positively correlated with respiratory intensity and soluble sugar content and negatively correlated with water loss rate, MDA and crude fibre content (p < 0.05) among the four antioxidant enzymes. APX and PAL were positively correlated with anthocyanin content and total phenols content, respectively. These results confirmed that 1−MCP could effectively maintain the storage quality of edible rose petals by increasing the antioxidant capacity of petals and prolong the storage period of fresh petals to 49 days.

Enormous enormous subgaleal hematoma with epidural extension, accompanying occipital bone's absorption is an uncommon complication of hemophilia A. A 30 years old man presenting scalp lump was found enormous enormous subgaleal hematoma with epidural extension, accompanying occipital bone's destruction by computed tomography (CT) scan, and laboratory examination indicated that the concentration of his factor VII was 2% of normal level. Further inquiring his medical history found that this patient has been suffering from hemophilia A diagnosed when he was 6 years old. He recovered well after receiving the therapertic methods of factor VII replacement and surgical decompression. This case tells us that patient suffering from enormous enormous subgaleal hematoma with epidural extension, accompanying occipital bone's destruction and hemophilia A could recover well as long as he is well treated. Keywords: Neurosurgery, Factor VII, Enormous subgaleal hematoma with epidural extension, occipital bone's destruction, Hemophilia A

As a result of the high specific strength/stiffness to mass ratio, filament wound composite pressure vessels are extensively used to contain gas or fluid under pressure. The ability to in-situ monitor the composite pressure vessels for possible damage is important for high-pressure medium storage industries. This paper describes an in-situ monitoring method to permanently monitor composite pressure vessels for their structural integrity. The sensor is made of a multi-walled carbon nanotube (MWCNT) that can be embedded in the composite skin of the pressure vessels. The sensing ability of the sensor is firstly evaluated in various mechanical tests, and in-situ monitoring experiments of a full-scale composite pressure vessel during hydraulic fatigue cycling and pressurization are performed. The monitoring results of the MWCNT sensor are compared with the strains measured by the strain gauges. The results show that the measured signal by the developed sensor matches the mechanical behavior of the composite laminates under various load conditions. In the hydraulic fatigue test, the relationship between the resistance and the strain is built, and could be used to quantitative monitor the filament wound pressure vessel. The bursting of the pressure vessel can be detected by the sharp increase of the MWCNT sensor resistance. Embedding the MWCNT sensor into the composite pressure vessel is successfully demonstrated as a promising method for structural health monitoring.

Aimed at portable application, a new integrated process chip for thin film bulk acoustic resonator (FBAR) mass sensor is proposed and verified with 0.18 um CMOS processing in this paper. The longitudinal mode FBAR with back-etched structure is fabricated, which has resonant frequency 1.878 GHz and factor 1200. The FBAR oscillator, based on the current-reuse structure, is designed with Modified Butterworth Van Dyke (MBVD) model. The result shows that the FBAR oscillator operates at 1.878 GHz with a phase noise of −107 dBc/Hz and −135 dBc/Hz at 10 KHz and 100 KHz frequency offset, respectively. The whole process chip size with pads is 1300 μm × 950 μm. The FBAR and process chip are bonded together to sense tiny mass. The measurement results show that this chip precision is 1 KHz with the FBAR frequency gap from 25 kHz to 25 MHz.

Hormone-sensitive lipase-knockout (HSL-/-) mice exhibit azoospermia for unclear reasons. To explore the basis of sterility, we performed the following three experiments. First, HSL protein distribution in the testis was determined. Next, transcriptome analyses were performed on the testes of three experimental groups. Finally, the fatty acid and cholesterol levels in the testes with three different genotypes studied were determined. We found that the HSL protein was present from spermatocyte cells to mature sperm acrosomes in wild-type (HSL+/+) testes. Spermiogenesis ceased at the elongation phase of HSL-/- testes. Transcriptome analysis indicated that genes involved in lipid metabolism, cell membrane, reproduction and inflammation-related processes were disordered in HSL-/- testes. The cholesterol content was significantly higher in HSL-/- than that in HSL+/+ testis. Therefore, gene expression and cholesterol ester content differed in HSL-/- testes compared to other testes, which may explain the sterility of male HSL-/- mice. [ABSTRACT FROM AUTHOR]