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Accurate liver tumor segmentation without contrast agents (non-enhanced images) avoids the contrast-agent-associated time-consuming and high risk, which offers radiologists quick and safe assistance to diagnose and treat the liver tumor. However, without contrast agents enhancing, the tumor in liver images presents low contrast and even invisible to naked eyes. Thus the liver tumor segmentation from non-enhanced images is quite challenging. We propose a Weakly-Supervised Teacher-Student network (WSTS) to address the liver tumor segmentation in non-enhanced images by leveraging additional box-level-labeled data (labeled with a tumor bounding-box). WSTS deploys a weakly-supervised teacher-student framework (TCH-ST), namely, a Teacher Module learns to detect and segment the tumor in enhanced images during training, which facilitates a Student Module to detect and segment the tumor in non-enhanced images independently during testing. To detect the tumor accurately, the WSTS proposes a Dual-strategy DRL (DDRL), which develops two tumor detection strategies by creatively introducing a relative-entropy bias in the DRL. To accurately predict a tumor mask for the box-level-labeled enhanced image and thus improve tumor segmentation in non-enhanced images, the WSTS proposes an Uncertainty-Sifting Self-Ensembling (USSE). The USSE exploits the weakly-labeled data with self-ensembling and evaluates the prediction reliability with a newly-designed Multi-scale Uncertainty-estimation. WSTS is validated with a 2D MRI dataset, where the experiment achieves 83.11% of Dice and 85.12% of Recall in 50 patient testing data after training by 200 patient data (half amount data is box-level-labeled). Such a great result illustrates the competence of WSTS to segment the liver tumor from non-enhanced images. Thus, WSTS has excellent potential to assist radiologists by liver tumor segmentation without contrast-agents. 相似文献
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目的 探讨蒙古族13个族群的身体密度,揭示蒙古族身体密度性别间、族群间差异,探讨身体密度与经度、纬度、年平均温度、年龄的相关性。 方法 测量肱三头肌皮褶、肩胛下皮褶厚度。按照日本长岭晋吉公式计算蒙古族13个族群的身体密度。 结果 蒙古族13个族群中,云南蒙古族身体密度值最大,额济纳土尔扈特部身体密度值最小。蒙古族身体密度族群间、性别间、年龄组间、4个地区间的差异均具有统计学意义。蒙古族男性女性身体密度均与经度、年龄成显著负相关。 结论 南方蒙古族身体密度值大于北方蒙古族,西部蒙古族身体密度大于东部蒙古族。 相似文献
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This study assessed the concentrations of heavy metals such as cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni) and zinc (Zn) in agricultural soils and crops (fruits, grains and vegetable) and their possible human health risk in Swat District, northern Pakistan. Cd concentration was found higher than the limit (0.05 mg/kg) set by world health organization in 95% fruit and 100% vegetable samples. Moreover, the concentrations of Cr, Cu, Mn, Ni and Zn in the soils were shown significant correlations with those in the crops. The metal transfer factor (MTF) was found highest for Cd followed by Cr > Ni > Zn > Cu > Mn, while the health risk assessment revealed that there was no health risk for most of the heavy metals except Cd, which showed a high level of health risk index (HRI ⩾ 10E-1) that would pose a potential health risk to the consumers. 相似文献
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BackgroundThere are unique challenges associated with measuring development in early childhood. Two primary sources of information are used: parent report and direct assessment. Each approach has strengths and weaknesses, particularly when used to identify and diagnose developmental delays. The present study aimed to evaluate consistency between parent report and direct assessment of child skills in toddlers with and without Autism Spectrum Disorder (ASD) across receptive language, expressive language, and fine motor domains.Method109 children were evaluated at an average age of two years; data on child skills were collected via parent report and direct assessment. Children were classified into three groups (i.e., ASD, Other Developmental Disorder, or Typical Development) based on DSM-IV-TR diagnosis. Mixed design ANOVAs, with data source as a within subjects factor and diagnostic group as a between subjects factor, were used to assess agreement. Chi square tests of agreement were then used to examine correspondence at the item level.ResultsResults suggested that parent report of language and fine motor skills did not significantly differ from direct assessment, and this finding held across diagnostic groups. Item level analyses revealed that, in most cases of significant disagreement, parents reported a skill as present, but it was not seen on direct testing.ConclusionsResults indicate that parents are generally reliable reporters of child language and fine motor abilities in toddlerhood, even when their children have developmental disorders such as ASD. However, the fullest picture may be obtained by using both parent report and direct assessment. 相似文献
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IntroductionInternet gaming disorder (IGD) is a novel behavioral addiction that influences the physical, mental, and social aspects of health due to excessive Internet gaming. One type of intensive treatment for IGD is the therapeutic residential camp (TRC), which comprises many types of therapies, including psychotherapy, psychoeducational therapy, and cognitive behavioral therapy. The TRC was developed in South Korea and has been administered to many patients with IGD; however, its efficacy in other countries remains unknown. We investigated the efficacy of the Self-Discovery Camp (SDiC), a Japanese version of a TRC, and the correlations between individual characteristics and outcome measures.MethodsWe recruited 10 patients with IGD (all male, mean age = 16.2 years, diagnosed using the DSM-5) to spend 8 nights and 9 days at the SDiC. We measured gaming time as well as self-efficacy (using the Stages of Change Readiness and Treatment Eagerness Scale, a measure of therapeutic motivation and problem recognition).ResultsTotal gaming time was significantly lower 3 months after the SDiC. Problem recognition and self-efficacy towards positive change also improved. Furthermore, there was a correlation between age of onset and problem recognition score.ConclusionsOur results demonstrate the effectiveness of the SDiC for IGD, especially regarding gaming time and self-efficacy. Additionally, age of onset may be a useful predictor of IGD prognosis. Further studies with larger sample sizes and control groups, and that target long-term outcomes, are needed to extend our understanding of SDiC efficacy. 相似文献
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Efficient detection of excess bilirubin in human serum and urine is highly important for the early diagnosis of infant jaundice. A highly stable Eu(iii)-based microporous framework with bent {Eu(COO)} chains interconnected by pairs of T-shaped 4,4′-(4,4′-bipyridine-2,6-diyl)dibenzoate (bpydb2−) linkers, {[Eu(H2O)(HCOO)(bpydb)]·solvent}n (1), was solvothermally synthesized and used as a chemical sensor for bilirubin response under clinically-applicable visible-light excitation. Due to the significant synergetic effect of the inner filter effect and photoinduced electron transfer, 1 can effectively probe trace amounts of bilirubin in aqueous solution through fluorescence decay with a strong quenching constant of 6.40 × 104 M−1 and low detection limit of 1.75 μM. More importantly, a portable test paper made from 1 was further developed to achieve qualitative, naked-eye visualized differentiation for the biomarker in clinical applications. These interesting findings highlight the importance of the π-conjugated antenna ligand for clinically applicable Ln-MOF sensors.A Eu(iii)–MOF sensor with intense red luminescence can effectively probe bilirubin in water through fluorescence decay, and can be fabricated into portable test papers to achieve visualized detection of bilirubin. 相似文献
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Qingchao Fan Chang Ma Liqiang Wu Chengbiao Wei Huihui Wang Yan Song Jingli Shi 《RSC advances》2019,9(12):6419
Porous carbon nanofibers are fabricated by one-step carbonization and activation of electrospun cellulose acetate (CA) nanofibres. Electrospun CA nanofibers were obtained by the electrospinning of a CA/DMAC/acetone solution, followed by deacetylation in NaOH/ethanol solution. One-step carbonization and activation was achieved by dipping the as-spun fibers in ZnCl2 solution, followed by one-step high temperature treatment. The effects of the concentration of the dipping solution on the microstructure of the CA-based carbon nanofibers (CACNFs), including the morphology, crystal structure, porous structure, specific surface area and surface chemical properties, have been investigated. The coating of ZnCl2 effectively improves the thermal stability of electrospun CA nanofibers and obviously enhances the oxygen-containing surface groups of the CACNFs. The CACNFs have a norrow pore size distribution (0.6–1.2 nm) and a high specific surface area (∼1188 m2 g−1). Electrochemical performances of the CACNFs were evaluated as supercapacitor electrodes in 6 M KOH solution. The CACNFs demonstrate high specific capacitance (202 F g−1 at 0.1 A g−1) and excellent rate capability (61% of the retention from 0.1 to 20 A g−1). After 5000 cycles of the electrode, the capacitance is maintained at 92%, and the coulombic efficiency is close to 100%, showing high electrochemical stability and reversibility. The renewable features and excellent performance make CACNFs quite a promising alternative to efficient supercapacitor electrodes for energy storage applications.Porous carbon nanofibers are fabricated by one-step carbonization and activation of electrospun cellulose acetate (CA) nanofibres. 相似文献