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Like many other cells, mammalian cardiac cells are able to divide and proliferate during development and during a short time after birth. However, the ability to divide decreases dramatically in the neonatal period, and adult cardiomyocytes are unable to proliferate. In contrast, postnatal cardiomyocytes from some lower vertebrates (e.g., zebrafish, newt) maintain the capability to divide, although the mechanisms underlying these species differences are unknown.

Because of the unreliability judgment of paddy rice’s nitrogen deficiency depending on the traditional artificial naked eye, in this article, the way of the paddy rice’s nitrogen deficiency examination based on image is put forward, to achieve the precise fast lossless detection and judgment on the paddy rice’s nitrogen. Based on the sorting function of SMV, paddy rice leaf's visible images are gathered, the texture features of image are extracted, the RBF nuclear function is chosen, the penalty coefficient C and the regularity coefficient ??are set, and the SVM sorting model is constructed. The recurrence sentencing rate to the training sample achieves 100%. The examination is caught on the test sample, and the accuracy rate of examination recognition achieve 95%, which indicates that the method of paddy rice’s nitrogen lossless examination judgment by image is effective and feasible to achieve the precise fast judgment on paddy rice’s nitrogen.

A perusal of experimental work on the neurobiology of brain aging shows that several investigations have been carried out on the theoretical bias that the aging process is quantitative in its nature, thus consisting in the progressive generalized weakening of biochemical (metabolic and specific) activities in the neuron, and leading to the impoverishment of brain functions which are typical of the species. In view of the perennity of the neuron, the factors underlying the aging process have been singled out in the deterioration of the nuclear function, especially with regard to protein synthesis, in reduced resistance to and increased formation of toxic wastes, mostly oxygen radicals, and consequent irreversible damage to enzymes, plasma membrane components, etc. Environmental impact on aging is believed to be exerted through these factors. The homogeneous character of these changes has recently been questioned, as in contrast to the ascertained prevailing selectivity of the changes for brain regions and cell types.1 Furthermore, the above interpretative frame of the nature and causation of the brain aging process disagrees with several experimental findings, notably the following.

Poly(ADP-ribose) has been expected to play some regulatory roles in nuclear functions. However, its amount and distribution in vivo have not yet been fully elucidated. An immunohistochemical method should be useful for the study of the natural occurrence of poly(ADP-ribose) at the cellular level. We have developed a highly sensitive immunohistochemical method for detecting poly(ADP-ribose) in conventional histological sections (1, 2).

In eukaryotic cells, chromatin function varies temporally and spatially with cell cycle and differentiation during development. One way a cell can control its chromatin function is thought to be by changing the configuration of chromatin. Post-translational modifications of chromosomal proteins have been proposed to be important in determining such conformational changes in chromatin structure. Since a minor but significant fraction of chromosomal proteins are reversibly poly(ADP-ribosyl)ated (1, 2) and the modification causes structural changes in chromatin (3, 4), it is assumed that the turnover of poly(ADP-ribose) on proteins has some biological role which is essential to expression of a nuclear function. Although a number of studies have shown that poly(ADP-ribosyl)ation may be involved in DNA repair and replication, gene expression, cell cycling, and differentiation, the physiological function of this modification has not yet been established (5).