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Highlights: The main mechanisms and clinical potential of sonodynamic therapy are emphasized. The nanomaterials provide new prospects and development directions for enhancing the treatment of cancer. Recent developments of sonodynamic therapy for deep tumors that are difficult to reach by traditional treatment, especially orthotopic cancers. Sonodynamic therapy (SDT) as an emerging modality for malignant tumors mainly involves in sonosensitizers and low-intensity ultrasound (US), which can safely penetrate the tissue without significant attenuation. SDT not only has the advantages including high precision, non-invasiveness, and minimal side effects, but also overcomes the limitation of low penetration of light to deep tumors. The cytotoxic reactive oxygen species can be produced by the utilization of sonosensitizers combined with US and kill tumor cells. However, the underlying mechanism of SDT has not been elucidated, and its unsatisfactory efficiency retards its further clinical application. Herein, we shed light on the main mechanisms of SDT and the types of sonosensitizers, including organic sonosensitizers and inorganic sonosensitizers. Due to the development of nanotechnology, many novel nanoplatforms are utilized in this arisen field to solve the barriers of sonosensitizers and enable continuous innovation. This review also highlights the potential advantages of nanosonosensitizers and focus on the enhanced efficiency of SDT based on nanosonosensitizers with monotherapy or synergistic therapy for deep tumors that are difficult to reach by traditional treatment, especially orthotopic cancers. [ABSTRACT FROM AUTHOR]

Objective: Hyperreflective foci (HRF) are small, punctate lesions ranging from 20 to 50 μ m and exhibiting high reflective intensity in optical coherence tomography (OCT) images of patients with diabetic retinopathy (DR). The purpose of the model proposed in this paper is to precisely identify and segment the HRF in OCT images of patients with DR. This method is essential for assisting ophthalmologists in the early diagnosis and assessing the effectiveness of treatment and prognosis. In this study, we introduce an HRF segmentation algorithm based on KiU-Net, the algorithm that comprises the Kite-Net branch using up-sampling coding to collect more detailed information and a three-layer U-Net branch to extract high-level semantic information. To enhance the capacity of a single-branch network, we also design a cross-attention block (CAB) which combines the information extracted from two branches. The experimental results demonstrate that the number of parameters of our model is significantly reduced, and the sensitivity (SE) and the dice similarity coefficient (DSC) are respectively improved to 72.90 % and 66.84 % . Considering the SE and precision(P) of the segmentation, as well as the recall ratio and recall P of HRF, we believe that this model outperforms most advanced medical image segmentation algorithms and significantly relieves the strain on ophthalmologists. Purpose: Hyperreflective foci (HRF) are small, punctate lesions ranging from 20 to 50 μm with high reflective intensity in optical coherence tomography (OCT) images of patients with diabetic retinopathy (DR). This study aims to develop a model that precisely identifies and segments HRF in OCT images of DR patients. Accurate segmentation of HRF is essential for assisting ophthalmologists in early diagnosis and in assessing the effectiveness of treatment and prognosis. Methods: We introduce an HRF segmentation algorithm based on the KiU-Net architecture. The model comprises two branches: a Kite-Net branch that uses up-sampling coding to capture detailed information, and a three-layer U-Net branch that extracts high-level semantic information. To enhance the capacity of the network, we designed a cross-attention block (CAB) that combines the information extracted from both branches, effectively integrating detail and semantic features. Results: Experimental results demonstrate that our model significantly reduces the number of parameters while improving performance. The sensitivity (SE) and Dice Similarity Coefficient (DSC) of our model are improved to 72.90% and 66.84%, respectively. Considering the SE and precision (P) of the segmentation, as well as the recall ratio and precision of HRF detection, our model outperforms most advanced medical image segmentation algorithms Conclusion: The proposed HRF segmentation algorithm effectively identifies and segments HRF in OCT images of DR patients, outperforming existing methods. This advancement can significantly alleviate the burden on ophthalmologists by aiding in early diagnosis and treatment evaluation, ultimately improving patient outcomes. [ABSTRACT FROM AUTHOR]

Convolutional neural networks have become a powerful tool for partial 3D object detection. However, their power has not been fully realized for focusing on global information, which is crucial for object detection. In this paper, we resolve the problem with a multi-feature voxel transformer (MVTr), an architecture that extracts long-range relationship features through self-attention between multi-feature voxels. In general, converting a point cloud to a voxel representation can reduce a lot of computation, but it would take a long process for the attention network to pay attention to the car voxels in a huge 3D real scene. To this end, we propose a semantic voxel module which takes semantic voxels as input and cooperates with a sparse and a non-empty voxel module to extract features. And the semantic voxels are generated from image segmentation and point cloud projection, which only retains a large number of car voxels. To further enlarge the attention range while maintaining a favorable computational, we propose two attention mechanisms for multi-head attention: local attention and stumpy attention. Finally, we propose the fusion attention module, which can add channel attention and spatial attention to the 2D backbone network. MVTr combines the semantic information of the image and the 3D information of the point cloud and can be applied to most 3D object detection tasks. Experimental results on KITTI dataset show that our method is effective, and the precision has significant advantages compared to other similar feature fusion-based methods. [ABSTRACT FROM AUTHOR]

Accumulation studies have found that adipose-derived stem cell (ADSC) exosomes have anti-oxidant and anti-inflammatory characteristics. The current study verified their therapeutic potential to elucidate mechanisms of ADSC exosome actions in ultraviolet B (UVB) light-induced skin injury. Exosomes were isolated from ADSCs and hypoxic pretreated ADSCs. Next-generation sequencing (NGS) was applied to characterize differential mRNA expression. A UV-induced mice skin injury model was generated to investigate therapeutic effects regarding the exosomes via immunofluorescence and ELISA analysis. Regulatory mechanisms were illustrated using luciferase report analysis and in vitro experiments. The results demonstrated that exosomes from hypoxic pretreated ADSCs (HExos) inhibited UVB light-induced vascular injury by reversing reactive oxygen species, inflammatory factor expression and excessive collagen degradation. NGS showed that HExos inhibits UV-induced skin damage via GLRX5 delivery, while GLRX5 downregulation inhibited the therapeutic effect of HExos on UV-induced skin damage. GLRX5 upregulation increased the protective Exo effect on UV-induced skin and EPC damage by inhibiting ferroptosis, inflammatory cytokine expression and excessive collagen degradation. Therefore, the data indicate that HExos attenuate UV light-induced skin injury via GLRX5 delivery and ferroptosis inhibition. [ABSTRACT FROM AUTHOR]

Purpose: This retrospective study aimed to determine the prevalence and morphological characteristics of accessory mandibular canals (AMCs) in an eastern Chinese population to provide clinical guidance for reducing intraoperative and postoperative complications. Methods: Cone beam computed tomography (CBCT) scans of 300 Chinese patients were used to identify AMCs according to a modification of Naitoh's classification. The length of the branch (L0) and the upper and lower angles between the branch and mandibular canal were measured on sagittal images. Additionally, the branches were divided into narrow or wide types by calculating the ratio of the branch diameter to the main canal diameter. The location of the bifurcation point was characterized by measuring its distance to the buccal wall of the mandible (L1), lingual wall of the mandible (L2) and alveolar ridge (L3). Results: The prevalence rate of AMCs was 40.7% (95% CI: 35.1–46.3), and the most common type was the retromolar canal, followed by the forward canal, dental canal, trifid mandibular canals (TMCs) or others, inferior canal and buccolingual canal. Twenty-one cases of multiple branches with unusual patterns were observed in the study. The average values of L0, L1, L2 and L3 were 15.05 ± 0.63 mm, 5.79 ± 0.14 mm, 4.40 ± 0.18 mm and 14.61 ± 0.31 mm, respectively. The mean upper angle and lower angle were 141.59° ± 2.44° and 50.64° ± 2.57°, respectively. Approximately 20.8% of the branches were defined as wide type, and no statistical significance was found between different types. Conclusion: AMCs are not rare anatomic variations of the mandibular canal in the eastern Chinese population; thus, CBCT examination is highly recommended for precise evaluation before surgeries involving the mandibles. [ABSTRACT FROM AUTHOR]

Nano-sized ZSM-5 zeolite was prepared via a vapor-phase transport method and then loaded with similar phosphorus content through different ways of phosphorus modification. These zeolites were characterized by XRD, SEM, N2 adsorption–desorption, NH3-TPD, FT-IR, etc., and the catalytic property of the zeolites in toluene alkylation with methanol was studied. The results showed that after phosphorus modification, the ratios of Brønsted to Lewis acid sites (B/L) and weak to strong acid sites (W/S) increased. It was found that higher B/L and W/S ratios of the catalysts were beneficial to improve the catalytic stability in toluene alkylation with methanol. The coke deposition rate of the phosphorus-modified ZSM-5 samples was lower than that of parent ZSM-5. There were great differences in the ratios of B/L and W/S of samples through different ways of phosphorus modification. The phosphorus-modified ZSM-5 using the incipient wetness impregnation method, having the highest ratios of B/L and W/S, exhibited the best catalytic stability and the highest toluene conversion in toluene alkylation with methanol. [ABSTRACT FROM AUTHOR]

Most existing image classification methods have achieved significant progress in the field of natural images. However, in the field of diabetic foot ulcer (DFU) where data is scarce and complex, the accurate classification of data is still a thorny problem. In this paper, we propose an Asymmetric Convolutional Transformer Network (ACTNet) for the multi-class (4-class) classification task of DFU. Specifically, in order to strengthen the expressive ability of the network, we design an asymmetric convolutional module in the front part of the network to model the relationship between local pixels, extract the underlying features of the image, and guide the network to focus on the central region in the image that contains more information. Furthermore, a novel pooling layer is added between the encoder and the classification head in the Transformer, which weights the data sequence generated by the encoder to better correlate the features between the input data. Finally, to fully exploit the performance of the model, we pretrained our model on ImageNet and fine-tune it on DFU images. The model is validated on the DFUC2021 test set, and the F1-score and AUC value are 0.593 and 0.824, respectively. The experiments show that our model has excellent performance even in the case of a small dataset. [ABSTRACT FROM AUTHOR]

The effects of cumulative deformation on the microstructure and texture of tubes were studied by preparing Ti-6Al-4V tubing by cold-rotary swaging (RS) with cross-sectional area deformation (ε) of 27%, 37%, 42%, and 51%. The grains of the tubing samples were obviously refined with increasing cold deformation. Orientation distribution function (ODF) cuts revealed that the maximum density level of the raw material was 4.51, with density reaching 6.68, 7.80, 8.66, and 10.17 for ε of 27%, 37%, 42%, and 51%, corresponding to increases of 48%, 73%, 92%, and 125%, respectively. Moreover, the tilt angle of the maximum density level of all the rotary-swaged tubes was less than 45°. It is thus feasible to use cold-rotary swaging to produce thin-walled Ti-6Al-4V seamless tubing with grain refinement and radial texture. [ABSTRACT FROM AUTHOR]

Ecological restoration actions to improve hydrologic conditions, including the construction of levees and freshwater release have been widely used to restore wetlands degraded by excessive soil salinity in coastal areas. However, the construction of levees for impoundments blocks the connectivity between the restored wetlands and the sea. In addition, freshwater inputs also altered some physical and chemical properties of the water bodies. In this study, stable isotopic compositions of primary producers and the shared consumers were analyzed to evaluate the impacts of these hydrologic changes on the function of the restored wetland ecosystems. After freshwater inputs, due to the change in salinity, the vegetation of the restored wetlands was replaced by the freshwater wetland vegetation. Although significant differences in the composition of basal sources existed, carbon stable isotope analyses indicated that there were no significant changes in source contribution between natural and restored wetlands for the shared consumers, with Suspended POM/ submersed aquatic vegetation being identified as contributing more carbon sources to consumers than emergent macrophytes/sediments. The construction of the impoundments eliminated the natural hydrological connection between the restored wetlands and the ocean, leading to the oligotrophic conditions in restored wetlands. For shared consumers, the δ15N values and trophic level positions in the restored wetlands became significantly lower than that in the natural wetlands. [ABSTRACT FROM AUTHOR]

Hydrological connectivity controls the patterns of invertebrate assemblages in wetland ecosystems. With degradation of intertidal wetlands, artificial freshwater release has become an important restoration technique. Hydrological connectivity with tidal creeks is also a key ecological process for intertidal wetlands. However, how hydrologic connectivity affects snail assemblages remains poorly investigated in intertidal wetlands. We studied the differences in snail assemblages in wetlands to understand the effects of hydrological connectivity, wetland to river, and wetland to ocean. We found freshwater connectivity can transform intertidal snail assemblages into freshwater snail assemblages; restored wetlands primarily had freshwater snail species and natural intertidal wetlands mainly supported marine or salt-adapted snail species. Cluster analysis, nMDS plot and ANOSIM analysis showed snail assemblages were influenced strongly by hydrological connectivity. Stenothyra glabra, Oncomelania sp. and Nassarius festivus were indicators of natural intertidal wetlands. Hippeutis cantori, Radix swinhoei and Succinea pfeifferi were indicators of restored wetlands. Our results suggest natural hydrological connectivity with the ocean needs to be maintained when attempting to restore intertidal wetlands. Without this connection, connecting impaired wetlands only to rivers, may not achieve restoration of natural biotic assemblages. [ABSTRACT FROM AUTHOR]

During the traditional process of texture testing, the sample to be tested must be flat. Generally, it is quite complicated and difficult to prepare the texture sample for the x-ray diffraction examination since it usually adopts time-consuming corrosion flattening or slice sticking for tubing. In this work, a new method is proposed to measure the texture of curved tube directly by using Eulerian Cradle installed on the x-ray diffractometer. This nondestructive method is favorable for a special defocusing correction sample composed of pure Ti powders with the same curvature radius as that of the tested Ti alloy tubing, and can be used to correct the strength loss caused by the elongated x-ray spot during the tube testing. It is verified that this nondestructive testing method is valid and feasible as compared to the traditional corrosion flattening method of tubing texture measurement. Moreover, this nondestructive testing method is highly effective, more accurate, and time-saving, which can be used for the rapid texture measurement for Ti alloy tubes. [ABSTRACT FROM AUTHOR]

Kinetics and mechanism of oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3in situ reaction were researched in air using vertical high temperature thermal dilatometer from 25 °C to 1 400 °C. It is shown that oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced Al4C3in situ reaction is the common logarithm of oxidation time t and the oxygen partial pressure P inside MgAl2O4 spinel carbon composites reinforced by Al4C3in situ reaction in air at 1 400 °C is as follows: P=F(−2.75×10−4A+2.13×10−3) lnt. The nonsteady diffusion kinetic equation of O2 at 1 400 °C inside the composites is as follows: J=De lnt. Acceleration of the total diffusional flux of oxygen inside the composites at 1 400 °C is in inverse proportion to the oxidation time. The nonsteady state effective diffusion coefficient De of O2(g) inside the composites decreases in direct proportional to the increase of the amount of metallic aluminium. The method of preventing the oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3in situ reaction is to increase the amount of Al. The slag erosion index of MgO-Al2O3 spinel carbon composite reinforced by Al4C3in situ reaction is 0.47 times that of MgO-CaO brick used in the lining above slag line area of a VOD stainless steel-making vessel. HMOR of MgO-Al2O3 spinel carbon composite reinforced by Al4C3in situ reaction is 26.7 MPa, HMOR of the composite is 3.6 times the same as that of MgO-CaO brick used in the lining above slag line area of a VOD vessel. Its service life is two times as many as that of MgO-CaO brick. [ABSTRACT FROM AUTHOR]

Hydration mechanism of tabular alumina carbon composites reinforced by AlC in situ reaction with Mg and Al was researched in water steam using super automatic thermostatic water bath from 25 °C to 85 °C. It is shown that hydration mechanism of the composites is chemical reaction control at 44.3 °C-84 °C in HO(g). The hydration was controlled by diffusion from 24.7 °C to 33 °C. The ratio of added Mg/Al influences the HMOR of the composites.The mechanism of HMOR of the composites with different ratios of Mg/Al can be discovered by means of SEM analysis. The active Mg/Al powder and flake graphite inside give the composites outstanding hot strength resulting from the interlocking structure of AlC crystals at high temperature. Besides, the matrix changes into the AlC with high refractoriness. The method of preventing the hydration of tabular alumina carbon composites reinforced by AlC in situ reaction was immersed in the wax at suitable temperature or storing them below 33 °C in a dry place or storing them with paraffin-coating. [ABSTRACT FROM AUTHOR]