A Modified Ant Colony Optimization Algorithm for Tumor Marker Gene Selection

Microarray data are often extremely asymmetric in dimensionality,such as thousands or even tens of thousands of genes but only a few hundreds of samples or less.Such extreme asymmetry between the dimensionality of genes and samples can lead to inaccurate diagnosis of disease in clinic.Therefore,it has been shown that selecting a small set of marker genes can lead to improved classification accuracy.In this paper,a simple modified ant colony optimization (ACO) algorithm is proposed to select tumor-related ma...     

Process Optimization,Characterization and Pharmacokinetic Evaluation in Rats of Ursodeoxycholic Acid–Phospholipid Complex

The purpose of this research was to study whether the bioavailability of ursodeoxycholic acid could be improved by administering ursodeoxycholic acid–phospholipid complex (UDCA–PLC) orally to rats. A central composite design approach was used for process optimization in order to obtain the acceptable UDCA–PLC. The physicochemical properties of the complex obtained by optimal parameters were investigated by means of scanning electron microscopy and X-ray diffraction. The pharmacokinetic parameters and bioavailability studies were conducted in rats of UDCA after oral administration of UDCA–PLC and UDCA tablet. Multiple linear regression analysis for process optimization revealed that the acceptable UDCA–PLC was obtained wherein the optimal values of X ₁, X ₂ and X ₃ were 3, 60°C and 3 h, respectively. The XRD studies of UDCA–PLC obtained by the optimal parameters demonstrated that UDCA and phospholipids in the UDCA–PLC were combined by non-covalent bonds, not form new compounds. But pharmacokinetic parameters of the complex in rats were T _max 1.6 h, C _max 0.1346 μg/ml, 11.437 μg·h/ml, respectively. The relative bioavailability of UDCA of UDCA–PLC was increased by 241%,compared with the reference ursodeoxycholic acid tablet.     

秦岭皇冠优势灌木苦糖果的空间分布格局及种内种间关联

以秦岭皇冠暖温性落叶阔叶林25 hm²森林样地中的优势灌木苦糖果为对象,研究了苦糖果不同径级个体的空间分布格局以及种内种间关系。结果表明: 苦糖果径级结构呈现出下宽上窄的金字塔型,小径级植株数量最多,更新状态较好,处于稳定增长阶段,有利于群落更新和演替。以Ripley's K函数为基础,采用单变量和双变量成对相关函数,在3个零模型(完全空间随机模型、异质泊松模型和先决条件模型)的处理下,树种整体和不同径级以聚集分布为主,且聚集程度随研究尺度的加大而逐渐减小,逐渐趋向随机分布。受到生境异质性、扩散限制、负密度制约等影响,种内不同径级个体之间以正关联为主,但也有一定程度的无关联,未出现负关联的情况。种间关系较为复杂,既有无关联,也有正关联和负关联,但以负关联和无关联为主。     

The effects of selection for gain in mice on the direct-maternal genetic correlation

Components of genetic variation for postweaning growth traits were estimated for both control and growth stocks of mice. The effect of phenotypic selection for gain, which genetically combines selection for additive direct and maternal effects, on additive genetic variance components, heritability, and additive genetic correlationsis discussed. Quantitative genetic theory predicts that simultaneous selection for two metric traits in the same direction will cause the genetic correlation between the two traits to become more negative. The results presented in this paper conflict with this theory. The direct-maternal additive genetic correlation was more negative in the control line (with 356 mice) than in the growth-selected line (with 320 mice) for the three traits analyzed (0.310 vs 0.999 for 21-day weight, 0.316 vs 1.000 for 42-day weight, and 0.506 vs 1.000 for gain from 21–42 days). Estimates were obtained by restricted maximum likelihood (REML) computed under a derivative free algorithm (DFREML).     

A novel ACO algorithm for optimization via reinforcement and initial bias

In this paper, we introduce the MAF-ACO algorithm, which emulates the foraging behavior of ants found in nature. In addition to the usual pheromone model present in ACO algorithms, we introduce an incremental learning component. We view the components of the MAF-ACO algorithm as stochastic approximation algorithms and use the ordinary differential equation (o.d.e.) method to analyze their convergence. We examine how the local stigmergic interaction of the individual ants results in an emergent dynamic programming framework. The MAF-ACO algorithm is also applied to the multi-stage shortest path problem and the traveling salesman problem. Research of Prof. V.S. Borkar was supported in part by grant no. III.5(157)/99-ET and a J.C. Bose Fellowship from the Department of Science and Technology, Government of India.     

Raspberry ketone-supplemented diet has no effect on fitness parameters or lure responsiveness in male melon flies,Zeugodacus cucurbitae (Diptera: Tephritidae)

The male annihilation technique (MAT) and sterile insect technique (SIT) are often used to control pestiferous tephritid fruit flies (Diptera: Tephritidae). MAT involves the deployment of traps containing a male attractant and insecticide with the goal of drastically reducing male abundance and ultimately eliminating the entire population. SIT, which involves the mass production, sterilization, and release of the target species, may also be implemented to achieve final extirpation. Generally, simultaneous implementation of MAT and SIT is counterproductive, because the presence of large numbers of male-specific traps in the environment (MAT) would greatly reduce the number of sterile males available for copulating with wild females (SIT). However, studies on the Queensland fruit fly, Bactrocera tryoni (Froggatt), indicate that concurrent use of MAT and SIT may be feasible. Sexually mature males of B. tryoni are attracted to the raspberry ketone and its synthetic analogue cue-lure. Males of B. tryoni fed raspberry-ketone-supplemented diet when newly emerged showed lower attraction to cue-lure baited traps than control males. In addition, newly emerged males provided this diet displayed accelerated sexual maturation, which would allow the early release of sterile males and reduce pre-release holding costs. Here, we examined whether the addition of raspberry ketone to the adult diet of male melon flies, Zeugodacus cucurbitae (Coquillett), produced effects similar to those observed for B. tryoni. Despite using similar methods, no significant effect of raspberry ketone-supplemented diet on time to sexual maturity, survival, mating competitiveness, or attraction to cue-lure baited traps in mass-reared Z. cucurbitae males.