A major theme in Darwinian evolutionary theory is that novelty arises through a process in which organisms and their features are gradually transformed. Morgan provided Darwinism and the evolutionary synthesis with the idea that minor mutations produce the minuscule morphological variations on which natural selection then acts, and that, although mutation is random, once a process of gradual ge...

Fluorescence measurements with single-molecule sensitivity are used to measure the hydrodynamic size and local pH of a weak polyelectrolyte, poly-2-vinyl pyridine end labeled with pH-sensitive dye, the polyelectrolyte having concentration so low (nanomolars) that molecular properties are resolvable only from fluorescence experiments and cannot be accessed by light scattering. We find that the l...

Arsenic trioxide has shown the excellent therapeutic efficiency for acute promyelocytic leukemia. Nowadays, more and more research focuses on the design of the arsenic drugs, especially organic arsenicals, and on the mechanism of the inducing cell death. Here we have synthesized some organic arsenicals with Schiff base structure, which showed a better antitumor activity for three different kind...

The purpose of this paper is to discuss the development of a theory of maternal postpartum role collapse. The influences of traditional role theory and symbolic interactionism are presented. The development of the maternal postpartum role collapse theory emerged from the study of postpartum depression among African-American women (Amankwaa, 2000). Major components of the theory of postpartum ma...

Diazinon is an organophosphate which is extensively used in trade and agriculture. Due to its widespread application, its toxicity is common. Several studies have shown that organophosphates are able to induce oxidative stress by generating free radicals and depletion of endogenous antioxidants. Pomegranate seed oil (PSO) possesses anti-inflammatory and antioxidant effects. In this study, the e...

abstract   background: the survival curves generally have been used for analysis of cell survival under stress conditions. they depict the relationship between the fraction of cells retaining their reproductive integrity and the absorbed dose. the median lethal dose, lethal concentration, 50% (lc 50 ) of a  toxin ,  radiation , or  pathogen  is the  dose required to kill half the members of a t...

In previous work we characterized a brain derived collapsing factor that induces the collapse of dorsal root ganglion growth cones in culture (Raper and Kapfhammer, 1990). To determine how the growth cone cytoskeleton is rearranged during collapse, we have compared the distributions of F-actin and microtubules in normal and partially collapsed growth cones. The relative concentration of F-actin...