Older adults favor emotionally positive material over emotionally negative material in information processing. Given the potentially harmful consequences of avoiding negative information, this aging positivity effect may provide benefits that offset its costs. To test this possibility, we assessed positivity in recall and blood indicators of immune function among older adults. Greater positivit...

Sarcomatoid carcinoma is a high‑grade rare malignant tumor with both epithelial and mesenchymal components. Sarcomatoid carcinoma in the upper urinary tract is very rare. We reported here a case of sarcomatoid carcinoma of renal pelvis with osteosarcomatous differentiation, with involvement of the ureter and renal parenchyma in a 68-year-old female. Histologically, predominant pleomorphic spind...

The classical regulator R of a number field K is given [F1] by a rapidly convergent series of the form R w = ∞

In this work we address the issue of integrating symmetric Riccati and Lyapunov matrix diierential equations. In many cases { typical in applications { the solutions are positive deenite matrices. Our goal is to study when and how this property is maintained for a numerically computed solution. There are two classes of solution methods: direct and indirect algorithms. The rst class consists of ...

We consider partial differential operators H = − div(C∇) in divergence form on R with a positive-semidefinite, symmetric, matrix C of real L∞-coefficients. First, we prove that one can define H as a selfadjoint operator on L2(R ) such that the corresponding semigroup extends as a positive, contraction semigroup to all the Lp-spaces. Secondly, we establish that H is strongly elliptic if and only...