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1.
In this paper, a high-order moment-based multi-resolution Hermite
weighted essentially non-oscillatory (HWENO) scheme is designed for hyperbolic conservation laws. The main idea of this scheme is derived from our previous work [J.
Comput. Phys., 446 (2021) 110653], in which the integral averages of the function and
its first order derivative are used to reconstruct both the function and its first order
derivative values at the boundaries. However, in this paper, only the function values at
the Gauss-Lobatto points in the one or two dimensional case need to be reconstructed
by using the information of the zeroth and first order moments. In addition, an extra
modification procedure is used to modify those first order moments in the troubled-cells, which leads to an improvement of stability and an enhancement of resolution
near discontinuities. To obtain the same order of accuracy, the size of the stencil required by this moment-based multi-resolution HWENO scheme is still the same as the
general HWENO scheme and is more compact than the general WENO scheme. Moreover, the linear weights are not unique and are independent of the node position, and
the CFL number can still be 0.6 whether for the one or two dimensional case, which has
to be 0.2 in the two dimensional case for other HWENO schemes. Extensive numerical
examples are given to demonstrate the stability and resolution of such moment-based
multi-resolution HWENO scheme. 相似文献
2.
3.
《Diagnostic and interventional imaging》2021,102(10):629-639
PurposeTo investigate the reproducibility of diffusion-weighted (DW) MRI and 18F-Fluorodeoxyglucose (18F-FDG)-Positron emission tomography/CT (PET/CT) in monitoring response to neoadjuvant chemotherapy in epithelial ovarian cancer.Materials and methodsTen women (median age, 67 years; range: 41.8–77.3 years) with stage IIIC-IV epithelial ovarian cancers were included in this prospective trial (NCT02792959) between 2014 and 2016. All underwent initial laparoscopic staging, four cycles of carboplatine-paclitaxel-based chemotherapy and interval debulking surgery. PET/CT and DW-MRI were performed at baseline (C0), after one cycle (C1) and before surgery (C4). Two nuclear physicians and two radiologists assessed five anatomic sites for the presence of ≥ 1 lesion. Target lesions in each site were defined and their apparent diffusion coefficient (ADC), maximal standardized uptake value (SUV-max), SUV-mean, SUL-peak, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were monitored (i.e., 10 patients × 5 sites × 3 time-points). Their relative early and late changes were calculated. Intra/inter-observer reproducibilities of qualitative and quantitative analysis were estimated with Kappa and intra-class correlation coefficients (ICCs).ResultsFor both modalities, inter- and intra-observer agreement percentages were excellent for initial staging but declined later for DW-MRI, leading to lower Kappa values for inter- and intra-observer variability (0.949 and 1 at C0, vs. 0.633 and 0.643 at C4, respectively) while Kappa values remained > 0.8 for PET/CT. Inter- and intra-observer ICCs were > 0.75 for SUV-max, SUL-peak, SUV-mean and their change regardless the time-point. ADC showed lower ICCs (range: 0.013–0.811). ANOVA found significant influences of the evaluation time, the measurement used (ADC, SUV-max, SUV-mean, SUV-max, SUL-peak, MTV or TLG) and their interaction on ICC values (P = 0.0023, P< 0.0001 and P =0.0028, respectively).ConclusionWhile both modalities demonstrated high reproducibility at baseline, only SUV-max, SUL-peak, SUV-mean and their changes maintained high reproducibility during chemotherapy. 相似文献
4.
培养“医信融合”复合型医学人才是医学高等教育在新时代信息技术发展背景下的历史使命。在引入“医信融合”教育理念的基础上,提出“医信融合”教育的人才培养目标及其内容体系,并据此构建了“医信融合”人才培养质量评价指标,提出了培养效果评价方法。介绍“医信融合”教育人才培养效果的评价方法,对山西医科大学“医信融合”教学效果进行实证分析,从而为“医信融合”教育实践提供借鉴。 相似文献
5.
Mariano E. Menendez Suleiman Y. Sudah Patrick J. Denard 《Seminars in Arthroplasty》2022,32(3):644-649
BackgroundThe growing enthusiasm for the use of reverse shoulder arthroplasty (RSA) in the treatment of primary glenohumeral osteoarthritis (GHOA) with an intact rotator cuff is based on data derived from single-center studies with limited generalizability and follow-up. This study compared patient-reported outcomes (PROs) between RSA and total shoulder arthroplasty (TSA) for the treatment of primary GHOA with up to 5-year follow-up and examined temporal trends in the treatment of GHOA between 2012 and 2021.MethodsA retrospective review was performed on patients with primary GHOA undergoing primary arthroplasty surgery from the Surgical Outcomes System global registry between 2012 and 2021. PROs including the American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation (SANE) score, and visual analog scale (VAS) for pain were compared between RSA and TSA at 1, 2, and 5 years postoperatively.ResultsA total of 4451 patients were included, with 2693 (60.5%) undergoing TSA and 1758 (39.5%) undergoing RSA. Both RSA and TSA provided clinically excellent outcomes at 1 year postoperatively (ASES: 80.8 ± 17.9 vs. 85.9 ± 15.2, respectively; SANE: 74.8 ± 24.7 vs. 79.5 ± 22.9; VAS pain: 1.3 ± 2.0 vs. 1.1 ± 1.7; all P < .05) that were maintained at 2 years (ASES: 81.3 ± 19.3 vs. 87.3 ± 14.9; SANE: 74.8 ± 26.2 vs. 79.7 ± 24.7; VAS pain: 1.3 ± 2.1 vs. 1.0 ± 1.6; all P < .05) and 5 years (ASES: 81.7 ± 16.5 vs. 86.9 ± 15.3; SANE: 71.6 ± 28.5 vs. 78.2 ± 25.9; VAS pain: 1.0 ± 1.7 vs. 1.0 ± 1.7; all P < .05), with statistical significance favoring TSA. After controlling for age and sex, there was an adjusted difference of 4.5 units in the ASES score favoring TSA (P = .005) at 5 years postoperatively but no differences in adjusted SANE (P = .745) and VAS pain (P = .332) scores. The use of RSA for GHOA grew considerably over time, from representing only 17% of all replacements performed for GHOA in 2012 to nearly half (47%) in 2021 (P < .001).ConclusionRSA as a treatment for GHOA with an intact rotator cuff seems to yield PROs that are largely clinically equivalent to TSA extending to 5 years postoperatively. The observed statistical significance favoring TSA appears to be of marginal clinical benefit based on established minimal clinically important differences and may be a result of the large sample size. Further research using more granular clinical data and examining differences in range of motion and complications is warranted as it may change the value analysis. 相似文献
6.
Pressure ulcers result in financial losses, including the cost of unnecessary medical expenses because of extended hospital stays, treatment, and examination. This was a retrospective, observational, methodological study to develop quality indicators related to pressure ulcer development and validate risk adjustment factors for pressure ulcer development. We performed a literature review to develop risk adjustment factors, and an expert group performed a content validity test. To validate risk adjustment factors for pressure ulcer development using electronic medical records, 127 patients admitted to a long-term care hospital in South Korea from June to September 2015 were enrolled in the study. Pressure ulcer risk factors were peripheral vascular disease, end-stage disease, past pressure ulcer history, high risk group for pressure ulcer development, fever, haemoglobin, and albumin (all P < 0.05); only albumin (odds ratio: 0.210, P < 0.001) was significantly associated with pressure ulcer development as an independent risk factor. Further research with a large sample size is needed for the validation of risk adjustment factors. Risk-adjusted quality indicators for pressure ulcer development can be used to evaluate the quality of nursing care and compare outcomes after preventive pressure ulcer care activities or between long-term care hospitals. 相似文献
7.
Pauline Carri Sverine Barry Elodie Rousset Rene de Crmoux Carole Sala Didier Calavas Jean‐Baptiste Perrin Anne Bronner Patrick Gasqui Emmanuelle Gilot‐Fromont Claire A. M. Becker Kristel Gache Elsa Jourdain 《Transboundary and Emerging Diseases》2019,66(3):1202-1209
Q fever is a zoonotic abortive disease of ruminants mostly transmitted by inhalation of aerosols contaminated by Coxiella burnetii. Clusters of cases or even epidemics regularly occur in humans but, to date, there is no consensus about the best way to carry out outbreak investigations in order to identify potential farms at risk. Although environmental samples might be useful during such investigations, there are few baseline data on the presence of C. burnetii in the environment of ruminant farms. We thus investigated dust samples from cattle, sheep and goat farm buildings in order to (a) estimate C. burnetii detection frequency and bacterial loads in the environment, and (b) determine whether this environmental contamination is associated with series of abortions attributed to Q fever. We considered 113 herds with a recent abortive episode potentially related (n = 60) or not (n = 53) to C. burnetii. Dust was sampled using a swab cloth and tested by a quantitative PCR method targeting the IS1111 gene. Coxiella burnetii DNA was detected on 9 of 50 cattle farms, 13 of 19 goat farms and 30 of 40 sheep farms. On 16 cloths, bacterial loads were higher than 108 genome equivalents, levels as high as in infectious materials such as placentas and aborted foetuses. Overall, the probability of detecting C. burnetii DNA was higher on small ruminant farms than cattle farms, in herds suspected of Q fever and in large herds. We conclude that swab cloths are a putative indicator of contamination of ruminant farms by C. burnetii. 相似文献
8.
Background
There were increased reports of fevers and febrile reactions in young children (particularly children aged <5?years) receiving the Seqirus/CSL Southern Hemisphere 2010 trivalent inactivated influenza vaccine (IIV3). Modifying the vaccine manufacturing process by increasing the minimum concentration of splitting agent (sodium taurodeoxycholate [TDOC]) from 0.5% w/v to 1.5% w/v for all strains resolved this issue. The current analysis compared fever rates in three pediatric studies of Seqirus IIV3 (S-IIV3) or quadrivalent inactivated influenza vaccine (S-IIV4), prepared using the modified manufacturing process, with fever rates in three pediatric studies of historical (pre-2010) IIV3 formulations. The historical IIV3 formulations, S-IIV3, and S-IIV4 had 0/3, 2/3, and 4/4 vaccine strains split at 1.5% TDOC, respectively.Methods
For each study, fever rates (any grade and severe) were determined for the following age subgroups (as applicable), using the fever intensity grading system used in the S-IIV3/S-IIV4 studies: 6?months to <3?years; 3 to <5?years; 5 to <9?years; and 9 to <18?years.Results
For each age subgroup, the any grade and severe fever rates were lower in the S-IIV3/S-IIV4 studies than in the historical IIV3 formulation studies, with the greatest differences in fever rates observed in the youngest age groups. In the 6?months to <3?years group, the any grade fever rate was 7.0% (severe fever: 2.5%) in one S-IIV4 study compared with 38.7% to 40.0% (severe fever: 9.6% to 17.8%) in the historical IIV3 formulation studies. In the 3 to <5?years subgroup, the any grade fever rate was 4.9% (severe fever: 1.2%) in one S-IIV4 study compared with 34.1% to 36.0% (severe fever: 6.3% to 16.5%) in the historical IIV3 formulation studies.Conclusion
This analysis provides clinical evidence that the modified manufacturing process improved the fever profile across all pediatric age groups, in particular, in children aged <5?years. 相似文献9.
10.
Tatiana Elghossain Sarah Bott Chaza Akik Hala Ghattas Carla Makhlouf Obermeyer 《The Journal of adolescent health》2019,64(1):8-19