4,151 research outputs found

    AdLER: Adversarial Training with Label Error Rectification for One-Shot Medical Image Segmentation

    Full text link
    Accurate automatic segmentation of medical images typically requires large datasets with high-quality annotations, making it less applicable in clinical settings due to limited training data. One-shot segmentation based on learned transformations (OSSLT) has shown promise when labeled data is extremely limited, typically including unsupervised deformable registration, data augmentation with learned registration, and segmentation learned from augmented data. However, current one-shot segmentation methods are challenged by limited data diversity during augmentation, and potential label errors caused by imperfect registration. To address these issues, we propose a novel one-shot medical image segmentation method with adversarial training and label error rectification (AdLER), with the aim of improving the diversity of generated data and correcting label errors to enhance segmentation performance. Specifically, we implement a novel dual consistency constraint to ensure anatomy-aligned registration that lessens registration errors. Furthermore, we develop an adversarial training strategy to augment the atlas image, which ensures both generation diversity and segmentation robustness. We also propose to rectify potential label errors in the augmented atlas images by estimating segmentation uncertainty, which can compensate for the imperfect nature of deformable registration and improve segmentation authenticity. Experiments on the CANDI and ABIDE datasets demonstrate that the proposed AdLER outperforms previous state-of-the-art methods by 0.7% (CANDI), 3.6% (ABIDE "seen"), and 4.9% (ABIDE "unseen") in segmentation based on Dice scores, respectively. The source code will be available at https://github.com/hsiangyuzhao/AdLER

    Monoclinic form of (Z)-1-ferrocenyl-3-(3-hy­droxy­anilino)but-2-en-1-one

    Get PDF
    The title compound, [Fe(C5H5)(C15H14NO2)], is a monoclinic polymorph of the previously reported triclinic form [Shi et al. (2006 ▶). Acta Cryst. C62, m407–m410]. The polymorphs feature the same strong intra­molecular N—H⋯O=C hydrogen bonds, but show different packing modes. The mol­ecules in the monoclinic form associate into double chains via O—H⋯O=C and (Cp)C—H⋯O—H inter­actions

    Direct phasing of one-wavelength anomalous-scattering data of the protein core streptavidin

    Get PDF
    The direct method [Fan, Hao, Gu, Qian, Zheng & Ke (1990). Acta Cryst. A46, 935-939] was used to break the phase ambiguity intrinsic to one-wavelength anomalous scattering data from a known protein of moderate size, core streptavidin, which was solved originally with three-wavelength anomalous diffraction data [Hendrickson, Pähler, Smith, Satow, Merritt & Phizackerley (1989). Proc. Natl Acad. Sci. USA, 86, 2190-2194]. Unlike that in the previous test with a small protein, the Fourier map calculated with the direct-method phases could not clearly reveal the moderate-sized protein structure. However, the phases can be improved step by step using Wang's solvent-flattening method, non-crystallographic symmetry averaging and the skeletonization method. The final electron-density map clearly shows most Calpha positions and some side chains and it is traceable without prior knowledge of the structure. It is concluded that the direct method is capable of breaking the OAS phase ambiguity of a moderate-sized protein at moderate resolution such as 3 A, while the combination of direct methods with macromolecular techniques may produce phases good enough for unknown protein structure to be traced

    Surgical treatment strategy for multiple injury patients in ICU

    Get PDF
    AbstractObjectiveTo investigate the surgical treatment for patients with multiple injuries in ICU.MethodsClinical data of 163 multiple injury patients admitted to ICU of our hospital from January 2006 to January 2009 were retrospectively studied, including 118 males and 45 females, with the mean age of 36.2 years (range, 5-67 years). The injury regions included head and neck (29 cases), face (32 cases), chest (89 cases), abdomen (77 cases), pelvis and limbs (91 cases) and body surface (83 cases). There were 57 cases combined with shock. ISS values varied from 10 to 54, 18.42 on average. Patients received surgical treatments in ICU within respectively 24 hours (10 cases), 24-48 hours (8 cases), 3-7 days (7 cases) and 8-14 days (23 cases).ResultsFor the 163 patients, the duration of ICU stay ranged from 2 to 29 days, with the average value of 7.56 days. Among them, 143 were cured (87.73%), 11 died in the hospital (6.75%) due to severe hemorrhagic shock (6 cases), craniocerebral injury (3 cases) and multiple organ failure (2 cases), and 9 died after voluntarily discharging from hospital (5.52%). The total mortality rate was 12.27%.ConclusionsThe damage control principle should be followed when multiple injury patients are resuscitated in ICU. Surgical treatment strategies include actively controlling hemorrhage, treating the previously missed injuries and related wounds or surgical complications and performing planned staging operations

    Scaling of Berry-curvature monopole dominated large linear positive magnetoresistance

    Full text link
    The linear positive magnetoresistance (LPMR) is a widely observed phenomenon in topological materials, which is promising for potential applications on topological spintronics. However, its mechanism remains ambiguous yet and the effect is thus uncontrollable. Here, we report a quantitative scaling model that correlates the LPMR with the Berry curvature, based on a ferromagnetic Weyl semimetal CoS2 that bears the largest LPMR of over 500% at 2 Kelvin and 9 Tesla, among known magnetic topological semimetals. In this system, masses of Weyl nodes existing near the Fermi level, revealed by theoretical calculations, serve as Berry-curvature monopoles and low-effective-mass carriers. Based on the Weyl picture, we propose a relation MR=eBΩF\text{MR}=\frac{e}{\hbar }B{{\Omega }_{\text{F}}}, with B being the applied magnetic field and ΩF{{\Omega }_{\text{F}}} the average Berry curvature near the Fermi surface, and further introduce temperature factor to both MR/B slope (MR per unit field) and anomalous Hall conductivity, which establishes the connection between the model and experimental measurements. A clear picture of the linearly slowing down of carriers, i.e., the LPMR effect, is demonstrated under the cooperation of the k-space Berry curvature and real-space magnetic field. Our study not only provides an experimental evidence of Berry curvature induced LPMR for the first time, but also promotes the common understanding and functional designing of the large Berry-curvature MR in topological Dirac/Weyl systems for magnetic sensing or information storage

    Undeca­carbonyl-μ2-methane­thiol­ato-μ2-[(pyridin-2-yl)methane­thiol­ato]-μ4-sulfido-tetra­iron(II)(2 Fe—Fe)

    Get PDF
    The title compound, [Fe4(C6H6NS)(CH3S)S(CO)11], com­prises two butterfly-shaped sub-cluster cores, Fe2S2N and Fe2S2, joined together by a spiro-type μ4-S atom. The (pyridin-2-yl)methane­thiol­ate ligand is attached to the Fe2(CO)5 unit in a μ-κN:κ2 S mode, and the methane­thiol­ate ligand is coordinated to the Fe2(CO)6 unit in a μ-κ2 S fashion

    The impact of cognitive training on cerebral white matter in community-dwelling elderly : one-year prospective longitudinal diffusion tensor imaging study

    Get PDF
    It has been shown that cognitive training (CogTr) is effective and recuperative for older adults, and can be used to fight against cognitive decline. In this study, we investigated whether behavioural gains from CogTr would extend to white matter (WM) microstructure, and whether training-induced changes in WM integrity would be associated with improvements in cognitive function, using diffusion tensor imaging (DTI). 48 healthy community elderly were either assigned to multi-domain or single-domain CogTr groups to receive 24 sessions over 12 weeks, or to a control group. DTI was performed at both baseline and 12-month follow-up. Positive effects of multi-domain CogTr on long-term changes in DTI indices were found in posterior parietal WM. Participants in the multi-domain group showed a trend of long-term decrease in axial diffusivity (AD) without significant change in fractional anisotropy (FA), mean diffusivity (MD) or radial diffusivity (RD), while those in the control group displayed a significant FA decrease, and an increase in MD and RD. In addition, significant relationships between an improvement in processing speed and changes in RD, MD and AD were found in the multi-domain group. These findings support the hypothesis that plasticity of WM can be modified by CogTr, even in late adulthood
    corecore