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Using deep neural networks to solve PDEs has attracted a lot of attentions recently. However, why the deep learning method works is falling far behind its empirical success. In this paper, we provide a rigorous numerical analysis on deep Ritz method (DRM) [47] for second order elliptic equations with Neumann boundary conditions. We establish the first nonasymptotic convergence rate in $H^1$ norm for DRM using deep networks with ${\rm ReLU}^2$ activation functions. In addition to providing a theoretical justification of DRM, our study also shed light on how to set the hyperparameter of depth and width to achieve the desired convergence rate in terms of number of training samples. Technically, we derive bound on the approximation error of deep ${\rm ReLU}^2$ network in $C^1$ norm and bound on the Rademacher complexity of the non-Lipschitz composition of gradient norm and ${\rm ReLU}^2$ network, both of which are of independent interest.  相似文献   
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Cancer Causes & Control - A disparity exists in cancer screening rates for the Sexual and Gender Minority (SGM) community. We sought to understand the perceptions and baseline knowledge of...  相似文献   
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BackgroundIn the phase III MDS-005 study of patients with lower-risk, non-del(5q) myelodysplastic syndromes, lenalidomide was associated with a higher rate of ≥ 8 weeks red blood cell transfusion independence (RBC-TI) compared with placebo, but also with a higher risk of hematologic adverse events (AEs).Patients and MethodsThis analysis evaluated the ratio of clinical benefit-risk in patients treated with lenalidomide or placebo, and assessed the effect of lenalidomide dose reductions on response. Clinical benefit was a composite endpoint defined as RBC-TI, transfusion reduction ≥ 4 units packed red blood cells, hemoglobin increase ≥ 1.5 g/dL, or cytogenetic response.ResultsThe rate of clinical benefit was higher with lenalidomide than with placebo (31.9% vs. 3.8%). The ratio of response (RBC-TI and clinical benefit) to risk (hematologic AEs) favored lenalidomide over placebo. Patients who underwent ≥ 1 lenalidomide dose reduction had a longer duration of treatment, received a higher cumulative dose, and were more likely to experience clinical benefit versus patients without dose reductions.ConclusionDespite the occurrence of hematologic AEs, the overall benefit-risk profile supported lenalidomide treatment. Appropriate management of hematologic AEs by dose reductions may help patients with myelodysplastic syndromes to remain on treatment and achieve clinical benefit.  相似文献   
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Journal of Neuro-Oncology - High-volume hospitals are associated with improved outcomes in glioblastoma (GBM). However, the impact of travel burden to high-volume centers is poorly understood. We...  相似文献   
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PurposeHepatoblastoma is the most common primary liver cancer of childhood and has few prognostic indicators. We have previously shown that Proviral Integration site for Moloney murine leukemia virus (PIM3) kinase decreased hepatoblastoma tumorigenicity. We sought to determine the effect of PIM3 overexpression on hepatoblastoma cells and whether expression of PIM3 correlated with patient/tumor characteristics or survival.MethodsThe hepatoblastoma cell line, HuH6, and patient-derived xenograft, COA67, were utilized. Viability, proliferation, migration, sphere formation, and tumor growth in mice were assessed in PIM3-overexpressing cells. Immunohistochemistry was performed for PIM3 on patient samples. Correlation between stain score and clinical/pathologic characteristics was assessed.ResultsPIM3 overexpression rescued the anti-proliferative effect observed with PIM3 knockdown. Sphere formation was increased in PIM3 overexpressing cells. Cells with PIM3 overexpression yielded larger tumors than those with empty vector. Seventy-four percent of samples expressed PIM3. There was no statistical difference in patient characteristics between subjects with strong versus weak PIM3 staining, but patients with strong PIM3 staining had decreased survival.ConclusionsPIM3 expression plays a role in hepatoblastoma tumorigenesis. PIM3 was present in the majority of hepatoblastomas and higher PIM3 expression correlated with decreased survival. PIM3 warrants investigation as a therapeutic target and prognostic marker for hepatoblastoma.  相似文献   
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In the current paper, we first describe the rationale for and methodology employed by an international research consortium, the Moral Injury Outcome Scale (MIOS) Consortium, the aim of which is to develop and validate a content‐valid measure of moral injury as a multidimensional outcome. The MIOS Consortium comprises researchers and clinicians who work with active duty military service members and veterans in the United States, the United Kingdom, the Netherlands, Australia, and Canada. We describe the multiphase psychometric development process being conducted by the Consortium, which will gather phenomenological data from service members, veterans, and clinicians to operationalize subdomains of impact and to generate content for a new measure of moral injury. Second, to illustrate the methodology being employed by the Consortium in the first phase of measure development, we present a small subset of preliminary results from semistructured interviews and questionnaires conducted with care providers (N = 26) at three of the 10 study sites. The themes derived from these initial preliminary clinician interviews suggest that exposure to potentially morally injurious events is associated with broad psychological/behavioral, social, and spiritual/existential impacts. The early findings also suggest that the outcomes associated with acts of commission or omission and events involving others’ transgressions may overlap. These results will be combined with data derived from other clinicians, service members, and veterans to generate the MIOS.  相似文献   
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