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1.
Guo-Quan Shi Huajun Zhu & Zhen-Guo Yan 《Communications In Computational Physics》2022,31(4):1215-1241
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
2.
Mark Verrill 《Surgery (Oxford)》2019,37(3):181-185
Multimodality primary therapies for breast cancer combined with earlier detection have led to a sharp decline in the death rate from breast cancer in the UK over the last 40 years in the face of a rising incidence. The latest UK statistics from Cancer Research UK report 55,122 new cases of breast cancer in 2015 with 11,563 deaths from breast cancer recorded in 2016. Crudely, this equates to a cure rate of around 80% for all comers and demonstrates a clear improvement in outcome with 50,285 new cases in 2011 and 11,716 deaths in 2012. Despite this good news, there are still significant numbers of women (and men) who suffer from either a local recurrence or metastatic disease following apparently successful treatment for early breast cancer (Stage I to III). Only a minority of individuals, 6.6% with the stage recorded at diagnosis, present with stage IV disease. This review considers the treatment options available to individuals with locally recurrent and advanced breast cancer (ABC). 相似文献
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Moises Rodriguez-Gonzalez Antonio Moruno Tirado Reza Hosseinpour Jose Santos de Soto 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(4):350-356
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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《The Journal of arthroplasty》2022,37(7):1338-1347
BackgroundMultimodal pain therapy combining analgesics, local infiltration analgesia (LIA) and peripheral nerve blocks, such as fascia iliaca compartment block (FICB), can improve postoperative pain, nausea and vomiting (PONV) and ambulation in patients undergoing total hip arthroplasty (THA). We hypothesized that addition of FICB would decrease opioid requirements and length of stay (LOS) but could create a motor block.MethodsThis is a single center, prospective, blinded randomized controlled study of 152 patients undergoing elective THA via direct anterior approach from October 2019 till August 2021. Three patient groups were defined: patients receiving only spinal anesthesia (control group, n = 53); spinal anesthesia with LIA perioperatively (n = 50); and spinal anesthesia with FICB on the recovery unit (n = 49). Outcome measures consisted of postoperative pain scores, PONV, length of hospital stay, opioid requirements and mobility.ResultsOverall pain scores were low for all patient groups, with a lower pain score for LIA in comparison to the control group until 4 hours postoperatively (P < .05). Length of hospital stay, postoperative pain, nausea and vomiting (PONV) scores and quadriceps muscle strength did not differ significantly between groups. The control group showed higher scores at 12 hours postoperatively in comparison to FICB regarding rehabilitation potential, use of walking aids and activities of daily living (P < .05), but all groups reached the same endpoint 48 hours postoperatively. The LIA and FICB groups required less opioids until 24 hours postoperatively.ConclusionLIA is a beneficial adjuvant therapy to spinal anesthesia in THA patients as it may decrease pain scores and the need for opioid consumption. Adjuvant FICB only provided lower opioid requirements. 相似文献
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Peter Marhofer Malachy Columb Phil M. Hopkins Manfred Greher Daniela Marhofer Max R. Levi Bienzle Markus Zeitlinger 《British journal of anaesthesia》2019,122(4):525-531