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A priori subcell limiting approach is developed for high-order flux reconstruction/correction procedure via reconstruction (FR/CPR) methods on two-dimensional unstructured quadrilateral meshes. Firstly, a modified indicator based on modal energy coefficients is proposed to detect troubled cells, where discontinuities exist. Then, troubled cells are decomposed into nonuniform subcells and each subcell has one solution point. A second-order finite difference shock-capturing scheme based on nonuniform nonlinear weighted (NNW) interpolation is constructed to perform the calculation on troubled cells while smooth cells are calculated by the CPR method. Numerical investigations show that the proposed subcell limiting strategy on unstructured quadrilateral meshes is robust in shock-capturing.  相似文献   
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目的:探讨改良三点式重睑术的临床应用疗效。方法:2012年6月-2019年6月,共165例单睑患者采用了改良三点式重睑术,沿术前标记线将三点处皮肤切开,剪刀将切口下唇的眼轮匝肌适当去除,同时将切口与切口在皮下层打通,剪除切口与切口之间的眼轮匝肌,6-0可吸收线挂睑板前筋膜或提上睑肌腱膜及切口下唇皮下组织缝合,三点切口各缝1针。再用6-0单丝尼龙线按照常规重睑线缝合方法挂切口下唇皮肤、睑板前筋膜或提上睑肌腱膜及切口上唇皮肤缝合打结,三点切口各缝1针。伴内眦赘皮者同时行内眦赘皮矫正术。结果:152例患者获得随访,随访患者大部分获得了比较满意的重睑,睁眼重睑流畅、自然,闭眼刀口痕迹不明显。2例患者出现内侧重睑线变浅,1例患者出现外侧重睑线变浅,所有患者均未出现重睑消失。5例患者双侧重睑线有轻度不对称。患者总体满意率为94.7%(144/152)。结论:改良三点式重睑术具有创伤小、并发症少、效果逼真、不易脱落、手术痕迹不明显等优点,值得推广应用。  相似文献   
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Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic.  相似文献   
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A typical time series in functional magnetic resonance imaging (fMRI) exhibits autocorrelation, that is, the samples of the time series are dependent. In addition, temporal filtering, one of the crucial steps in preprocessing of functional magnetic resonance images, induces its own autocorrelation. While performing connectivity analysis in fMRI, the impact of the autocorrelation is largely ignored. Recently, autocorrelation has been addressed by variance correction approaches, which are sensitive to the sampling rate. In this article, we aim to investigate the impact of the sampling rate on the variance correction approaches. Toward this end, we first derived a generalized expression for the variance of the sample Pearson correlation coefficient (SPCC) in terms of the sampling rate and the filter cutoff frequency, in addition to the autocorrelation and cross‐covariance functions of the time series. Through simulations, we illustrated the importance of the variance correction for a fixed sampling rate. Using the real resting state fMRI data sets, we demonstrated that the data sets with higher sampling rates were more prone to false positives, in agreement with the existing empirical reports. We further demonstrated with single subject results that for the data sets with higher sampling rates, the variance correction strategy restored the integrity of true connectivity.  相似文献   
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Spine deformities could be considered a possible manifestation of the childhood hypotonia, typical feature of Kleefstra Syndrome (KS). There is a paucity of literature describing posterior spinal fusion in the Kleefstra syndrome patient. For patients who develop severe scoliotic curve, bracing is often ineffective and surgery is recommended. We report the first corrective surgery for scoliosis in one patient with KS.We describe a case of 13-year-old female with severe developmental scoliosis in KS. Preoperative examination showed a thoracolumbar scoliosis with left convex thoracic curve (T3-T9, 97°) and right convex thoracolumbar curve (T9-L3, 88°). Posterior correction, pedicle screw fixation and bone graft fusion T3-L5 was performed. Postoperatively, the thoracic curve was corrected to 33° while the thoracolumbar one to 26° and better standing posture was obtained. Six month follow-up images showed no loosening of the hardware. The patient is still in our follow-up program.Scoliosis seems to be a rare evenience of the severe hypotonia of patients with KS. We report the first case of scoliosis in KS treated successfully with surgery. Corrective surgery for spinal deformity, such as scoliosis, could help in posture and improve the quality of life especially in complicated patients such as syndromic ones.  相似文献   
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