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Notes: The scientific view of aging is still rather fragmented, because no sound unifying aging theory yet exists. Most hypotheses are rather limited, in the sense that they describe only the some aspect of the aging phenomenon, summarized in the aspect theory of aging. But it cannot be denied that the majority of hypotheses are based on a deterministic view of aging. This kind of concept presents a single strategy of aging control wholly dependent on the replacement principle, which purports the substitution of all possible tools, such as genes, cells, tissues and organs. But, recently a novel aging concept has been proposed, based on the possible control of aged cells. Therefore, the new concept of aging and a novel approach for the development of a strategic pathway to aging control are introduced, which may hopefully result in functional longevity.The concept that aging is an irreversible, inevitable, universal process of an organism provides the basis of the deterministic view of aging. The underlying view of aging as a determined irresistible fate has conjured many hypothesis on the aging process such as aging clock hypothesis, genetic determinism, telomere hypothesis, wearing hypothesis, disposable soma hypothesis and error catastrophe hypothesis, etc. Although these hypotheses are under debates, the majority of scientists and the public are inclined to accept these ideas, preoccupied by the view that aging is a natural irresistible process leading to death. Based on the deterministic view on aging, it would be natural to adopt the replacement principle as the ultimate strategy for counteracting the aging process.In other words, if the aging process were irreversible, inevitable, irresistible and universal, only the replacement principle provides a solution, that is, just substitute the aged material with new fresh material. Many replacement principles have been developed at various levels from genes to organs. However, when we examine the replacement principle, many gloomy aspects of its approaches can be identified. At the gene level, the fundamental question of existence of gerontogene has not been resolved, though many virtual gerontogenes have been suggested. In terms of the cell therapy approach, stem cell have recently attracted a great deal of attention, but still the problem of the stem cell niche and the mode of regulating stem cell development have not been unveiled. At the tissue or organ level, tissue patches, artificial organs and the transplantation approach have been elaborately pursued. However, it is well known that these methods are restricted because of our limited knowledge on the complex of coordinated development, bionanotechnology and immuno-compatibility, etc. This reality encourages to depend on camouflage transient strategies such as plastic surgery or hormonal supplementation.The complex nature of aging, denying the consensus explanation of aging, has led us to pursue historic views of aging. The core problem in understanding the aging process is the traditional prejudice concerning aging as a one-way phenomenon based on the deterministic view. However, the aging process has now been revealed to be a reactive phenomenon based on adaptive response and designed to maintain the purpose of an organism, its LIFE. Aging-related complicated changes in metabolism, signal transduction, stress response, cytoskeletal modulation, and in genetic control are adaptive and responsive, as opposed to the deterministic programmed systems, presumed to be operating in the aging process. Therefore, it is natural that large differences in the aging process are observed not only at the individual level but also at the interorgan level in the same individuals.In our previous papers, we have reported that increased levels of caveolin are mainly responsible for the hyporesponsiveness of senescent cells through the modulation of receptor-mediated endocytosis. And we have shown that the senescent phenotype of growth factor response loss can be resumed by simply reducing the caveolin status. Moreover, the adjustment of the caveolin status of old cells restored not only their functional efficiencies by adjusting the signal transduction apparatus but also their structural features, probably by modulating focal adhesion complex activities.Therefore, it can be tentatively concluded that the fundamental notion of aging as a process of functional deterioration and morphological alteration are affected by caveolin status. Such data suggest that caveolin plays the role of gatekeeper in the aging process, for if increased, aging results, but if decreased, the senescent phenotype disappears. In addition to caveolins, there seem to be several other tentative gatekeeper molecules, such as amphiphysin and some G proteins.If the existence of a molecular gatekeeper for aging were assumed, it would be natural to suppose that an aging field could be generated inside a cell, as regulated by the gatekeeper. This novel concept would explain the aging phenotype as an adaptive responsive phenomenon toward environmental stress. Since caveolin is one of the candidate gatekeepers, its simple increase or decrease might be responsible for many aspects of the aging phenotype. Therefore, we suggest that the aging phenotype can be explained in terms of a new aging hypothesis, namely the gate theory of aging. The characteristic features of this novel view of aging are its focus upon flexibility rather than irreversibility, manageability rather than inevitability, and individuality rather than generality.The gate theory of aging implies the possibility of adjusting the aging phenotype. Based on this theory, the restoration principle can be proposed as a novel approach to aging control. For example, the effect of nutrition and exercise, which result in changes in cellular cholesterol content and promoter methylation status, would profoundly influence the cellular caveolin status. Therefore, it can be presumed that the aging phenotype can be adjusted to induce restoration by modulating gatekeeper molecules, illustrated by caveolin. There may be many other tools, which can be used to augment the actions of aging-related gatekeepers.As society enters a new era of longevity, never before experienced problems concerning the elderly are generated at the social, economic, environmental, medical and cultural levels. However, most problems are based on the traditional concept of aging; that is the deterministic view on aging as an irreversible, inevitable, inefficient status. But, now it is clear that the aging process can be explained in a totally different way, as an adaptive response to age, which implies the possibility of restoration by adjusting the cellular apparatus. Actually, this new aspect of aging is readily illustrated by the superlongevity of people like centenarians. There are now many centenarians in good shape with a good status, and sound social skills.The active attitude and the positive way of life shown by centenarians present the longlive community with a new concept; functional longevity. The adoption of this approach to life marks revolutionary conversion of the view of aging from simple longevity to functional longevity. The concept of functional longevity incorporates active participation, positive thinking, and responsible behavior. It may be concluded that the concept of functional longevity based on the gate theory of aging may be used to solve the emerging problems associated with aging and aged societies.〈section xml:id="abs1-1"〉〈title type="main"〉References 1. Cho, K.A., Ryu, S.J., Oh, Y.S., Park, J.H., Lee, J.W., Kim, K.T., Jang, I.S. and Park, S.C. Morphological adjustment of senescent cells by modulating caveolin-1 status. J. Biol. Chem. (2004) (epublication ahead of print).2. Cho, K.A., Ryu, S.J., Park, J.S., Jang, I.S., Ahn, J.S., Kim, K.T. and Park, S.C. Senescent phenotype can be reversed by reduction of caveolin status. J. Biol. Chem.278, 27789–27795 (2

Notes: During titanium silicide (TiSi2) formation by rapid thermal annealing (RTA), the redistribution of implanted arsenic was investigated by means of Auger electron spectroscopy (AES) and secondary-ion mass spectroscopy (SIMS). By using 30 nm amorphous silicon (a-Si) film deposited sequentially on 50 nm titanium film without breaking the vacuum, the As dopant redistribution is suppressed due to the reduction of consumption of silicon substrate (Si-sub) during TiSi2 formation. The AES shows that the silicon, which is required for TiSi2 formation, is supplied from the a-Si film more rapidly than from the Si-sub. Also, the conversion of deposited Ti film into TiSi2 is complete because the a-Si film on Ti film prevents the infiltration of oxygen impurity into the Ti film during the exposure to air before annealing.

Notes: The defect structures of GaAs film on (001) Si substrate tilted ∼3° towards the [110] direction were investigated by the high-resolution transmission electron microscopy. GaAs films were grown by the molecular beam epitaxy (MBE) on the Si (001) substrate by a modified two-step process, in which amorphous GaAs buffer layers were grown first. High-resolution electron micrographs show that stacking faults (and/or microtwins) are preferentially formed on the tilted step-rich surface, whereas misfit dislocations are preferentially formed on the flat surface. However, the difference in the defect density on the two cross sections is small. Between the observed 90° edge and 60° misfit dislocations the density of the latter is higher irrespective of the substrate tilt. This occurrence is explained by the difference in distribution of initial nucleating islands between the present and the conventional two-step MBE techniques.

Notes: Thin films of GaAs on Si were grown by molecular beam epitaxy, which involves the solid phase epitaxial (SPE) growth of the amorphous GaAs buffer layer. A Rutherford backscattering minimum channeling yield of ∼9.4% has been obtained for a 0.8-μm-thick GaAs film. Cross-sectional transmission electron micrographs and reflection high-energy electron diffraction results have revealed that misfit dislocations are mostly confined to what used to be the buffer layer of ∼300 nm in thickness, and that the microtwins (and/or stacking faults) are mostly originated from the GaAs/Si interface and are generated during SPE growth.

Notes: RT–PCR amplification of tumour-specific mRNA has been used for the detection of cancer cells in peripheral blood.〈section xml:id="abs1-2"〉〈title type="main"〉Aim:To evaluate the characteristics of the tumour specific mRNA species in peripheral blood of stomach cancer patients.〈section xml:id="abs1-3"〉〈title type="main"〉Methods:We analysed CEA, GalNAc-T, MUC-1, c-MET and hTERT mRNA expression in the stomach cancer cell lines and tissues, lymph nodes and peripheral blood of stomach cancer patients using RT–PCR.〈section xml:id="abs1-4"〉〈title type="main"〉Results:In RT–PCR analysis of the peripheral blood, 4%, 8%, 21%, 46%, and 100% of stomach cancer patients were positive for CEA, GalNAc-T, c-MET, hTERT and MUC-1 mRNA, respectively, but MUC-1 mRNA was also positive in all normal blood samples. The detection of hTERT mRNA was correlated with poor differentiation (P=0.01) and lymph node metastasis (P=0.009). The presence of c-MET mRNA was correlated with T stage (P=0.025), lymph node metastasis (P=0.036), distant metastasis (P=0.031), and stage of the stomach cancer (P=0.023).〈section xml:id="abs1-5"〉〈title type="main"〉Conclusions:Our study suggest that hTERT mRNA in peripheral blood can be a molecular marker for gastric cancer. We also showed that each molecular marker can be correlated with the clinicopathological features of the patients.

Notes: : Color is one of the determinant sensory qualities for green tea. As cold tea beverages in clear bottles are getting more popular, the traditional evaluation methods are gradually being altered to attach more importance to the tea infusion color. For quality control, experiments were carried out on 10 green tea samples to investigate the compounds influencing the colors of dry tea leaves and infusions. By calculating the coefficients of determination between the greenness (expressed in tristimulus data) and chemical composition, chlorophylls proved to be the influential compounds for the color of dry tea leaves; water-insoluble chlorophylls were also released from the fragile tea leaves during infusion and increased both the greenness and turbidity of tea infusions. Among the flavonoids (catechins and flavonols) detected in green tea infusions, quercetin was shown to be the most important phenolic compound contributing to the greenness of tea infusion.

Notes: Abstract The geometry and internal structures of modern sediments on the inner shelf off the southeastern coast of Korea were investigated by means of analysing high-frequency (3.5 kHz) seismic records. The records reveal a wedge-shaped sediment body, tapering off toward the sea. On the basis of reflection patterns, the sediments can be classified into two units; “foreset” (prodelta) unit and “bottomset” unit, consisting of sandy muds and clays, respectively. The lateral transition from foreset to bottomset deposits suggests a prograding delta system of the Nakdong River since the late Holocene.

Notes: Abstract The Korea (Tsushima) Strait is an important seaway through which the warm Tsushima Current flows into the East Sea (Japan Sea). A paleogeographic map constrained by a regional sea-level curve developed on the basis of a number of recent 14C radiocarbon dates suggests that the Korea Strait was not closed during the last glacial period. Rather, it was open as a channel-like seaway linking the western North Pacific and the East Sea. Some fraction of the paleo-Tsushima Current inflow presumably continued at that time through the Korea Strait. The activity of the paleo-Tsushima Current is evidenced by the distribution pattern of river-derived lowstand deposits, consisting of a beach/shoreface complex and lowstand deltaic wedges.

Notes: Abstract Jinhae Bay, a semi-enclosed, tide-dominated coastal embayment on the southeastern coast of Korea, receives large amounts of sediment derived from the Nakdong River. The irregular surface of the acoustic basement is overlain by a modern sedimentary sequence up to 25 m thick, characterized by an acoustically semitransparent subbottom. Sediments, consisting mainly of terrigenous and bioturbated mud, accumulate at a rate of 2–5 mm/yr. About 21% of the suspended sediments discharged from the Nakdong River, that is approximately 1.0 × 106 tons per year, accumulate in Jinhae Bay. Modern sedimentation began probably at about 5000 yr BP, when sea level approached its present level.