120 research outputs found

    Comparative study of tapered versus conventional cylindrical balloon for stent implantation in stenotic tapered artery

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    The natural tapering of coronary arteries often creates a dilemma for optimal balloon sizing during stenting. The influence of different balloon types, namely, a tapered balloon and a conventional cylindrical balloon, on the mechanical performance of the stent as well as arterial mechanics was investigated via the finite element method. Stent free-expansion and stent deployment in a stenotic tapered artery were investigated numerically. The biomechanical behavior of the two balloon types was compared in terms of stent foreshortening, stent deformation, stent stress distribution, and arterial wall stress distribution. Results indicate that balloon types affect the transient behavior of the stent and the arterial mechanics. Specifically, a tapered balloon could maintain the natural tapering of the coronary artery after stent expansion. In contrast to a cylindrical balloon, tapered balloon also mitigated the foreshortening of the stent (7.69%) as well as the stress concentration in the stent and artery (8.61% and 4.17%, respectively). Hence, tapered balloons should be used in tapered arteries as they may result in low risk of artery injury. This study might provide insights for improved balloon choice and presurgical planning

    Evolution of an intron-poor cluster of the CIPK gene family and expression in response to drought stress in soybean

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    Calcium ion is an intracellular messenger that plays a central role in signal transduction pathways. Calcineurin B-like proteins (CBLs) and CBL-interacting protein kinases (CIPKs) signal network have shown different functions in the Ca2+ signaling process. In this work, we identified the entire soybean (Glycine max) CIPK gene family, which comprised 52 genes and divided into four subgroups (I to IV) based on phylogeny. The gene structural analysis separated these 52 genes into an intron-rich clade and an intron-poor clade. Chromosomal location analysis resulted in the identification of 22 duplicated blocks and six tandem duplication events. Phylogenetic classification of 193 CIPK proteins from representative plant species suggested that the intron-poor clade of CIPKs originated in seed plants. Analysis of global gene expression patterns of soybean CIPK family revealed that most intron-poor soybean CIPK genes are drought-inducible; a finding that was further confirmed using qRT-PCR. Our study provides a foundation for further functional analysis to reveal the roles that CIPKs and more specifically the intron-poor clade play in drought tolerance in soybean

    Towards Robust Aspect-based Sentiment Analysis through Non-counterfactual Augmentations

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    While state-of-the-art NLP models have demonstrated excellent performance for aspect based sentiment analysis (ABSA), substantial evidence has been presented on their lack of robustness. This is especially manifested as significant degradation in performance when faced with out-of-distribution data. Recent solutions that rely on counterfactually augmented datasets show promising results, but they are inherently limited because of the lack of access to explicit causal structure. In this paper, we present an alternative approach that relies on non-counterfactual data augmentation. Our proposal instead relies on using noisy, cost-efficient data augmentations that preserve semantics associated with the target aspect. Our approach then relies on modelling invariances between different versions of the data to improve robustness. A comprehensive suite of experiments shows that our proposal significantly improves upon strong pre-trained baselines on both standard and robustness-specific datasets. Our approach further establishes a new state-of-the-art on the ABSA robustness benchmark and transfers well across domains.Comment: 10pages,1 figure,10 table

    Microwave-assisted non-thermal hemp degumming

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    The microwave-assisted non-thermal degumming of hemp fibre has been studied and then compared with the water bath heating under different time and temperature conditions. The results show that the residual gum content of the lean hemp using microwave-assisted heating method is lower than that obtained using water bath heating. The residual gum content gap between the two degumming processes increases first and then decreases as the heating time and temperature are increased. This proves the existence of non-thermal effects in microwave heating process besides the thermal effects in water bath heating. In addition, the structures of the lean hemp fibres obtained from these two methods are also studied by scanning electron microscopy and fourier transform infrared spectroscopy.

    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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