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We study improved shrinkage estimation of a vector of non-negative means. We concentrate on the Gaussian case with known scale, but do not necessarily assume the initial estimator is minimax. As a result, we find improved shrinkage estimators in fewer than 3 dimension in certain cases. Generalized Bayes estimators which may be improved via shrinkage in 1 and 2 dimensions illustrate the result. We also consider improved positive part estimators.

We investigate improved loss estimation in the matrix mean estimation problem. Specifically, for estimators of a normal mean matrix, we consider estimation of the Frobenius loss. Based on the singular values of the observation, we develop loss estimators that dominate the unbiased loss estimator for a broad class of matrix mean estimators including the Efron–Morris estimator. This is an extension of the results of Johnstone (1988) for a normal mean vector. We also provide improved estimators of loss for reduced-rank estimators. Numerical results show the effectiveness of the proposed loss estimators.

This report describes a case of esophageal intramural pseudodiverticulosis associated with an inflammatory esophageal mass with high 18F-fluorodeoxyglucose (FDG) uptake. A 48-year-old man presented with dysphagia caused by an esophageal stricture. Simultaneous positron emission tomography and magnetic resonance imaging showed an FDG-avid lesion in the lower esophagus. Because of suspected malignancy, the patient underwent subtotal esophagectomy. Histologic examination confirmed the diagnosis of an inflammatory tumor associated with esophageal pseudodiverticulosis. Unlike typical cases, this patient's pseudodiverticula involved both the submucosa and the muscularis propria. This case suggests that esophageal intramural pseudodiverticulosis can manifest with a tumorlike mass that may be FDG positive in response to associated inflammation.

This study computes the gradient of a function of numerical solutions of ordinary differential equations (ODEs) with respect to the initial condition. The adjoint method computes the gradient approximately by solving the corresponding adjoint system numerically. In this context, Sanz-Serna [SIAM Rev., 58 (2016), pp. 3–33] showed that when the initial value problem is solved by a Runge–Kutta (RK) method, the gradient can be exactly computed by applying an appropriate RK method to the adjoint system. Focusing on the case where the initial value problem is solved by a partitioned RK (PRK) method, this paper presents a numerical method, which can be seen as a generalization of PRK methods, for the adjoint system that gives the exact gradient.

Pitman closeness for Bayes shrinkage procedures in normal models are investigated. In point estimation, priors in the Strawderman class dominate the uniform prior. In predictive density estimation, spherically symmetric superharmonic priors dominate the uniform prior under log loss.

BackgroundLentinan (LNT) is a purified β-1, 3-glucan that augments immune responses. The present study was conducted to assess the efficacy of LNT in combination with S-1 as a first-line treatment for unresectable or recurrent gastric cancer.Patients and methodsEligible patients were randomly assigned to receive S-1 alone or S-1 plus LNT. The primary end-point was overall survival (OS). Secondary end-points were time-to-treatment failure (TTF), overall response rate (ORR), safety, quality of life (QOL), and biomarker. The percentages of LNT-binding monocytes in peripheral blood prior to treatment were analysed for the biomarker assessment.ResultsOne hundred and fifty-four and 155 patients were randomly assigned to receive S-1 alone or S-1 plus LNT, respectively. The median OS was 13.8 and 9.9 months (P = 0.208), the median TTF was 4.3 and 2.6 months (P

We contrast Pitman closeness and risk evaluations for Bayes procedures in point estimation and predictive density estimation problems when the mean of the underlying normal distribution is restricted to be nonnegative. Interesting reversals in preferences arise.

The mammalian Ror family receptor tyrosine kinases, Ror1 and Ror2, play crucial roles in developmental morphogenesis. Although the functions of Ror1 and Ror2 are redundant, Ror2 exhibits more specific functions during development. We show that when expressed in mammalian cells, Ror2, but not Ror1, associates with the melanoma-associated antigen (MAGE) family protein, Dlxin-1, which is known to bind to the homeodomain proteins Msx2 and Dlx5 and regulate their transcriptional functions. This association requires the cytoplasmic C-terminal region of Ror2, containing proline-rich and serine/threonine-rich domains, and the C-terminal necdin homology domain of Dlxin-1. Interestingly, the cytoplasmic C-terminal region of Ror2 is missing in patients with brachydactyly type B. Interestingly, transient expression and immunohistochemical analyses reveal that both Dlxin-1 and Msx2 are co-localized in the nuclei in the absence of Ror2. In the presence of Ror2, Dlxin-1 is co-localized with Ror2 at the membranous compartments and Msx2 is retained in the nuclei. It was also found that the majority of cellular Dlxin-1 is retained in the membrane fractions of wild-type but not Ror2 –/– mouse embryonic fibroblasts. Furthermore, we show that transcriptional activity of Msx2, irrespective of Ror2 kinase activity, is regulated by ectopic expression of Ror2 using a reporter plasmid containing the WIP element. Thus, Ror2 sequesters Dlxin-1 in membranous compartments, thereby affecting the transcriptional function of Msx2.

In mammals, the Ror-family receptor tyrosine kinases consist of two structurally related proteins, Ror1 and Ror2, characterized by the extracellular Frizzled-like cysteine-rich domain and membrane proximal kringle domains. As an attempt to gain insights into their roles in mouse development, expression patterns of Ror1 and Ror2 during early embryogenesis were examined and compared. Interestingly, at early stages, Ror1 and Ror2 exhibit similar expression patterns in the developing face, including the frontonasal process and pharyngeal arches, which are derived from cephalic neural crest cells. On the other hand, they exhibit different expression patterns in the developing limbs and brain, where the expression of Ror2 was detected broadly compared with that of Ror1. At a later stage, both genes are expressed in a similar fashion in the developing heart and lung, yet in a distinct manner in the brain and eye.