209 research outputs found

    Getting Sick After Seeing a Doctor? Diagnosing and Mitigating Knowledge Conflicts in Event Temporal Reasoning

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    Event temporal reasoning aims at identifying the temporal relations between two or more events. However, knowledge conflicts arise when there is a mismatch between the actual temporal relations of events in the context and the prior knowledge or biases learned by the model. We first systematically define distinct kinds of bias in event temporal reasoning, which include event relation prior bias, tense bias, narrative bias, and dependency bias, as indicators to study knowledge conflicts. To mitigate such event-related knowledge conflict, we introduce a Counterfactual Data Augmentation based method that can be applied to both Pre-trained Language Models (PLMs) and Large Language Models (LLMs) either as additional training data or demonstrations for In-Context Learning. Experiments suggest the importance of mitigating knowledge conflicts in event temporal reasoning tasks for reducing hallucination and highlight the potential of counterfactual data augmentation for improving model performance.Comment: 13 pages, 1 figur

    Low-frequency Image Deep Steganography: Manipulate the Frequency Distribution to Hide Secrets with Tenacious Robustness

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    Image deep steganography (IDS) is a technique that utilizes deep learning to embed a secret image invisibly into a cover image to generate a container image. However, the container images generated by convolutional neural networks (CNNs) are vulnerable to attacks that distort their high-frequency components. To address this problem, we propose a novel method called Low-frequency Image Deep Steganography (LIDS) that allows frequency distribution manipulation in the embedding process. LIDS extracts a feature map from the secret image and adds it to the cover image to yield the container image. The container image is not directly output by the CNNs, and thus, it does not contain high-frequency artifacts. The extracted feature map is regulated by a frequency loss to ensure that its frequency distribution mainly concentrates on the low-frequency domain. To further enhance robustness, an attack layer is inserted to damage the container image. The retrieval network then retrieves a recovered secret image from a damaged container image. Our experiments demonstrate that LIDS outperforms state-of-the-art methods in terms of robustness, while maintaining high fidelity and specificity. By avoiding high-frequency artifacts and manipulating the frequency distribution of the embedded feature map, LIDS achieves improved robustness against attacks that distort the high-frequency components of container images

    How is it effective for farmers to adopt environmentally friendly cultivated land protection technology: a configurational perspective

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    The adoption of environmentally friendly farmland conservation techniques by farmers is an important way to effectively curb agricultural surface pollution and promote the conservation of farmland quality. Based on 425 farmers’ in-depth interview data, a fuzzy-set qualitative comparative analysis method was used to construct a psychological cognition (farmers’ awareness and willingness to participate)—external context (organizational linkages and government regulation)—behavioral effect model to reveal the conditional configuration and multivariate paths of psychological cognition and external contextual factors influencing farmers’ behavioral effects on the adoption of environmentally friendly farmland conservation technologies. The results show that individual behavioral decision factors do not influence the behavioral effects of farmers. The results show that individual behavioral decision factors are not necessary to drive the effective adoption of environmentally friendly farmland conservation technologies and that multiple decision factors interact to form three sets of configurations that enhance the behavioral effectiveness of farmers, summarized as the willingness-to-participate dominant model, the internal and external constraints dominant model, and the external context dominant model

    A novel nanoparticle drug delivery system based on PEGylated hemoglobin for cancer therapy

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    Proteins such as albumin, gelatin, casein, transferrin, and collagen are widely used as drug delivery systems. However, only albumin-based paclitaxel (PTX) formulation AbraxaneVR (PTX-albumin NPs prepared by nab-technology) has been successfully developed for treating metastatic breast cancer clinically due to abundant materials, simple industrial scale-up process, and well tumor-targeting ability. Hemoglobin (Hb) is another protein used for drug delivery with similar advantages. In this study, we successfully synthesized PEG-Hb nanoparticles loading with PTX based on previously well-established acid-denatured method. PEG-Hb-PTX NPs showed enhanced cellular uptake and great cellular inhibition ability in vitro. Moreover, our animal study showed that PEGylated NPs greatly accumulated in tumor tissues and exhibited excellent anticancer activity in vivo. We found that PEG-Hb-PTX NPs possess a better in vivo antitumor effect than the commercially available TaxolVR formulation. We believe that PEG-Hb has great potential as an efficient drug delivery system for further clinic study

    Synergistic strategy with hyperthermia therapy based immunotherapy and engineered exosomes−liposomes targeted chemotherapy prevents tumor recurrence and metastasis in advanced breast cancer

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    Advanced breast cancer with recurrent and distal organ metastasis is aggressive and incurable. The current existing treatment strategies for advanced breast cancer are difficult to achieve synergistic treatment of recurrent tumors and distant metastasis, resulting in poor clinical outcomes. Herein, a synergistic therapy strategy composed of biomimetic tumor-derived exosomes (TEX)-Liposome-paclitaxel (PTX) with lung homing properties and gold nanorods (GNR)-PEG, was designed, respectively. GNR-PEG, with well biocompatibility, cured recurrent tumors effectively by thermal ablation under the in situ NIR irradiation. Meanwhile, GNR-mediated thermal ablation activated the adaptive antitumor immune response, significantly increased the level of CD8+ T cells in lungs and the concentration of serum cytokines (tumor necrosis factor-Îą, interlekin-6, and interferon-Îģ). Subsequently, TEX-Liposome-PTX preferentially accumulated in lung tissues due to autologous tumor-derived TEX with inherent specific affinity to lung, resulting in a better therapeutic effect on lung metastasis tumors with the assistance of adaptive immunotherapy triggered by GNR in vivo. The enhanced therapeutic efficacy in advanced breast cancer was a combination of thermal ablation, adaptive antitumor immunotherapy, and targeted PTX chemotherapy. Hence, the synergistic strategy based on GNR and TEX-Liposome provides selectivity to clinical treatment of advanced breast cancer with recurrent and metastasis

    Measurement and temporal and spatial characteristics of agricultural eco-efficiency under climate change: a case study of Anhui, China

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    IntroductionAgricultural eco-efficiency is an important index to evaluate the agricultural sustainable development and ecological economics, while simultaneously providing a metric for improvements to the rural environment and the stability of agricultural ecosystems.MethodsThis study took Anhui province as a case, and applied unit survey and list analysis methodologies to quantify rural agricultural non-point source pollution (NPS). Input-oriented super-efficient DEA-SBM was used to measure agricultural eco-efficiency in the typical North-South Transition Zone, and evaluated spatial correlations and differences.ResultsThis study showed that NPS was relatively stable, with less than 5% local variation in Chemical Oxygen Demand (COD), Total Nitrogen (TN), and Total Phosphorus (TP) pollutants. The environmental pressure caused by livestock breeding and the use of chemical fertilizers was very substantial, and the differences of rural agricultural NPS in Anhui Province had obvious north-south characteristics. The agricultural eco-efficiency exhibited an “inverted N” trend. Affected by the “Spatial proximity effect” and the “Matthew effect”, it presented spatial agglomeration and positive spatial correlation. The regional differences were significant, and the heterogeneity increased in our study areas. The southern region had the greatest variation, followed by the northern region, with the smallest variation in the central region, although inter-regional differences were consistent.DiscussionThough the rational allocation of resources, coordination between agricultural economic and environmental protection would be realized, and better conditions for the sustainable development of agricultural ecology and the long-term stability of agricultural ecosystem would be created

    Topically applied liposome-in-hydrogels for systematically targeted tumor photothermal therapy

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    Transdermal drug delivery for local or systemic therapy provides a potential anticancer modality with a high patient compliance. However, the drug delivery efficiency across the skin is highly challenging due to the physiological barriers, which limit the desired therapeutic effects. In this study, we prepared liposome-in-hydrogels containing a tumor targeting photosensitizer IR780 (IR780/lipo/gels) for tumor photothermal therapy (PTT). The formulation effectively delivered IR780 to subcutaneous tumor and deep metastatic sites, while the hydrogels were applied on the skin overlying the tumor or on an area of distant normal skin. The photothermal antitumor activity of topically administered IR780/lipo/gels was evaluated following laser irradiation. We observed significant inhibition of the rate of the tumor growth without any toxicity associated with the topical administration of hydrogels. Collectively, the topical administration of IR780/lipo/gels represents a new noninvasive and safe strategy for targeted tumor PTT

    Yes‐Associated Protein Inhibits Transcription of Myocardin and Attenuates Differentiation of Vascular Smooth Muscle Cell from Cardiovascular Progenitor Cell Lineage

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135973/1/stem2484_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135973/2/stem2484.pd

    NIR molecule induced self-assembled nanoparticles for synergistic in vivo chemo-photothermal therapy of bladder cancer

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    Bladder cancer (BC) is one of the commonest malignancies in the urinary system. Bladder cancer is divided into non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC) according to the depth of invasion. Besides, the prognosis of MIBC remains poor. Surgical resection combined with radiotherapy or chemotherapy is the standard treatment for MIBC. However, the major obstacle that hinders successful chemotherapy is its lack of tumor targeting. Here, we fabricated nanoparticles that respond to near-infrared laser irradiation in order to increase the drug accumulation at the tumor sites and combine chemotherapy with photothermal therapy to overcome challenges of bladder cancer treatment. IR780 and Doxorubicin (DOX)were loaded into albumin nanoparticles (IR780-DOX@Albumin NPs). In the process of IR780-DOX@Albumin NPs synthesis, the near-infrared molecule IR780 was used as the assembly molecular bridge. Under irradiation, the nanoparticles were decomposed due to the degradation of IR780 while the release of DOX increased. Nanoparticles can be ingested by tumor cells in a short time. The IR780- DOX@Albumin NPs were sensitive to near-infrared laser irradiation. Near-infrared laser irradiation can promote the release of the drugs from the nanoparticles and induce a photothermal effect, thus destroying the tumor cells. Given the excellent tumor-targeting ability and negligible toxicity to normal tissue, IR780-DOX@Albumin NPs can greatly increase the concentration of chemotherapeutic drugs in tumor cells. This study combines photothermal therapy and chemotherapy to treat MIBC, so as to avoid chemotherapy resistance, reduce the toxicity to normal cells, and achieve the purpose of improving the treatment of MIBC
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