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Background Purpose Methods Results Conclusions Deformable image registration is an essential technique of medical image analysis, which plays important roles in several clinical applications. Existing deep learning‐based registration methods have already achieved promising performance for the registrations with small deformations, while it is still challenging to deal with the large deformation registration due to the limits of the image intensity‐similarity‐based objective function.To achieve the image registration with large‐scale deformations, we proposed a multilevel network architecture FCNet to gradually refine the registration results based on semantic feature consistency constraint and flow normalization (FN) strategy.At each level of FCNet, the architecture is mainly composed to a FeaExtractor, a FN module, and a spatial transformation module. FeaExtractor consists of three parallel streams which are used to extract the individual features of fixed and moving images, as well as their joint features, respectively. Using these features, the initial deformation field is estimated, which passes through a FN module to refine the deformation field based on the difference map of deformation filed between two adjacent levels. This allows the FCNet to progressively improve the registration performance. Finally, a spatial transformation module is used to get the warped image based on the deformation field. Moreover, in addition to the image intensity‐similarity‐based objective function, a semantic‐feature consistency constraint is also introduced, which can further promote the alignments by imposing the similarity between the fixed and warped image features. To validate the effectiveness of the proposed method, we compared our method with the state‐of‐the‐art methods on three different datasets. In EMPIRE10 dataset, 20, 3, and 7 fixed and moving 3D computer tomography (CT) image pairs were used for training, validation, and testing respectively; in IXI dataset, atlas to individual image registration task was performed, with 3D MR images of 408, 58, and 115 individuals were used for training, validation, and testing respectively; in the in‐house dataset, patient to atlas registration task was implemented, with the 3D MR images of 94, 3, and 15 individuals being training, validation, and testing sets, respectively.The qualitative and quantitative comparison results demonstrated that the proposed method is beneficial for handling large deformation image registration problems, with the DSC and ASSD improved by at least 1.0% and 25.9% on EMPIRE10 dataset. The ablation experiments also verified the effectiveness of the proposed feature combination strategy, feature consistency constraint, and FN module.Our proposed FCNet enables multiscale registration from coarse to fine, surpassing existing SOTA registration methods and effectively handling long‐range spatial relationships. [ABSTRACT FROM AUTHOR]

Hemorrhagic fever with renal syndrome caused by hantaviruses has long been a serious public health issue in Yunnan Province. Hantaviruses exhibit a high extent of biodiversity in their natural hosts, particularly in mammalian hosts. This study was conducted to screen for hantaviruses in bats and rodents in Yunnan Province and elucidate their genetic characteristics and possible zoonotic disease risk. Hantaviruses were detected in 202 bats and 372 rodents with the positive rates 27.49% and 1.25% respectively. A novel lineage (named Lineage 10) of the Seoul virus (SEOV) from rodents and the geographic clustering of hantavirus in bats were identified using phylogenetic analyses of the full-length M- and S-segments. Our study suggest a high cross-species transmissibility of hantaviruses in bats and existence of a new lineage of SEOV in rodents differing significantly from other SEOVs. These results provide data to support the prevention and control of hantavirus-associated diseases in Yunnan Province. Author summary: Hantavirus is an important pathogen that can cause hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). HFRS has long been a serious public health problem in Yunnan Province. However, the molecular epidemiology and host characteristics of hantavirus in Yunnan Province are still unclear. Therefore, we screened hantaviruses in bats and rodents in selected areas of Yunnan from 2018 to 2022 and found the 10th SEOV lineage in rodents, as well as new geographic clusters of Xuan son virus (XSV) and novel hantavirus in bats. We proposed the possibility of the 10th SEOV lineage in rodents as an ancestral lineage and explained the related host-switching events in bat hantaviruses. These results provide data to reveal a greater risk of zoonotic disease and support the prevention and control of hantavirus-associated diseases and in Yunnan Province. [ABSTRACT FROM AUTHOR]

Purpose: To address the application requirements of soft actuators in rehabilitation training gloves, and in combination with ergonomic requirements, we designed a segmented soft actuator with bending and elongation modules. This actuator can achieve independent or coupled movements of the finger joints. Methods: A finite element model of the joint actuator was established to compare the driving performance of actuators with different structural forms. Numerical calculations were used to analyze the effects of structural size parameters on the bending characteristics and end output force of the actuator. The design was then refined based on these analyses. Results: The joint actuator designed in this study demonstrated a 71% increase in bending angle compared to the standard fast pneumatic network structure. Key factors affecting the driving performance include the thickness of the constraint layer, the inner wall thickness of the chamber, chamber height, chamber width, chamber spacing, chamber length, and the number of chambers. After improvements, the bending angle of the joint actuator increased by 60.6%, and the output force increased by 145.9%, indicating significant improvement. Conclusion: This study designed and improved a soft actuator for hand rehabilitation training, achieving independent and coupled joint movements. The bending angle, bending shape, and joint driving force of the soft actuator meet the requirements for finger rehabilitation training. [ABSTRACT FROM AUTHOR]

The monoamine transporters, including the serotonin transporter (SERT), dopamine transporter (DAT), and norepinephrine transporter (NET), are the therapeutic targets for the treatment of many neuropsychiatric disorders. Despite significant progress in characterizing the structures and transport mechanisms of these transporters, the regulation of their transport functions through dimerization or oligomerization remains to be understood. In the present study, we identified a conserved intramolecular ion-pair at the third extracellular loop (EL3) connecting TM5 and TM6 that plays a critical but divergent role in the modulation of dimerization and transport functions among the monoamine transporters. The disruption of the ion-pair interactions by mutations induced a significant spontaneous cross-linking of a cysteine mutant of SERT and an increase in cell surface expression but with an impaired specific transport activity. On the other hand, similar mutations of the corresponding ion-pair residues in both DAT and NET resulted in an opposite effect on their oxidation-induced dimerization, cell surface expression, and transport function. Reversible biotinylation experiments indicated that the ion-pair mutations slowed down the internalization of SERT but stimulated the internalization of DAT. In addition, cysteine accessibility measurements for monitoring SERT conformational changes indicated that substitution of the ion-pair residues resulted in profound effects on the rate constants for cysteine modification in both the extracellular and cytoplasmatic substrate permeation pathways. Furthermore, molecular dynamics simulations showed that the ion-pair mutations increased the interfacial interactions in a SERT dimer but decreased it in a DAT dimer. Taken together, we propose that the transport function is modulated by the equilibrium between monomers and dimers on the cell surface, which is regulated by a potential compensatory mechanism but with different molecular solutions among the monoamine transporters. The present study provided new insights into the structural elements regulating the transport function of the monoamine transporters through their dimerization. [ABSTRACT FROM AUTHOR]

Transformative tourism experiences are powerful life moments with the capacity to elevate individuals' well-being. With the rise of transformative tourism and the growing attention to well-being, theoretical research is needed to outline the underlying processes that connect transformative tourism experiences with individual well-being. This study employed grounded theory to critically analyze a set of travel blogs that narrate individual tourists' transformative tourism experiences. Specifically, we explored how sets of activities during transformative tourism (e.g., backpacker tourism, volunteer tourism, and study tours) contributed to travelers' hedonic and eudaimonic well-being. We took psychological needs as processes of well-being realization to construct an integrated "activities–needs–well-being" conceptual framework to demonstrate how transformative tourism contributes to travelers' hedonic and eudaimonic well-being. [ABSTRACT FROM AUTHOR]