The Cardinality Constraint-Based Optimization problem is investigated in this note. In portfolio optimization problem, the cardinality constraint allows one to invest in assets out of a universe of N assets for a pres...
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The Cardinality Constraint-Based Optimization problem is investigated in this note. In portfolio optimization problem, the cardinality constraint allows one to invest in assets out of a universe of N assets for a prespecified value of K. It is generally agreed that choosing a “small” value of K forces the implementation of diversification in small portfolios. However, the question of how small must be K has remained unanswered. In the present work, using a comparative approach we show computationally that optimal portfolio selection with a relatively small or large number of assets, K, may produce similar results with differentiated reliabilities.
Aim:A“seed”of lung cancer metastasis is circulating tumor cells(CTCs),which may be dislodged from a tumor during *** possibility was assessed among patients who underwent lung tumor biopsy using flexible fiber-topic...
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Aim:A“seed”of lung cancer metastasis is circulating tumor cells(CTCs),which may be dislodged from a tumor during *** possibility was assessed among patients who underwent lung tumor biopsy using flexible fiber-topic bronchoscopy(FFB).Methods:The study involved six patients with non-small cell lung cancer who underwent FFB biopsy to diagnose a lesion pathologically(5 males and 1 female,median age 63 years,6 adenocarcinomas,of 4 clinical-stage IA,1 stage IB,and 1 stage IIIA),CTCs were extracted from the peripheral vein blood at pre-FFB and at post-FFB using a size selection ***:No t umor c ell was d etected a t p re-a nd p ost-FFB was i n t hree c ases(50%);no tumor cells were detected pre-FFB while CTCs were detected at post-FFB in two cases(33.3%);and CTCs were detected at pre-FFB with numerous CTCs detected at post-FFB in one case(17.7%).In addition,similar tendencies were observed in each analysis of single-cell and clustered-cell ***:These results suggest that a FFB biopsy of lung cancer may potentially dislodge CTCs from a tumor into the circulating peripheral blood.
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