• Nutrition Research and Practice
• /
• v.5 no.3
• /
• pp.214-218
• /
• 2011

Diets based on carbohydrates increase rapidly the blood glucose level due to the fast conversion of carbohydrates to glucose. High glucose diets have been known to induce many lifestyle diseases. Here, we demonstrated that high glucose diet shortened the lifespan of Caenorhabditis elegans through apoptosis induction. Control adult groups without glucose diet lived for 30 days, whereas animals fed 10 mg/L of D-glucose lived only for 20 days. The reduction of lifespan by glucose diet showed a dose-dependent profile in the concentration range of glucose from 1 to 20 mg/L. Aging effect of high glucose diet was examined by measurement of response time for locomotion after stimulating movement of the animals by touching. Glucose diet decreased the locomotion capacity of the animals during mid-adulthood. High glucose diets also induced ectopic apoptosis in the body of C. elegans, which is a potent mechanism that can explain the shortened lifespan and aging. Apoptotic cell corpses stained with SYTO 12 were found in the worms fed 10 mg/L of glucose. Mutation of core apoptotic regulatory genes, CED-3 and CED-4, inhibited the reduction of viability induced by high glucose diet, which indicates that these regulators were required for glucose-induced apoptosis or lifespan shortening. Thus, we conclude that high glucose diets have potential for inducing ectopic apoptosis in the body, resulting in a shortened lifespan accompanied with loss of locomotion capacity.

• Nutrition Research and Practice
• /
• v.8 no.5
• /
• pp.533-538
• /
• 2014

BACKGROUND/OBJECTIVES: We investigated the effect of Pycnogenol (Pyc) on survival and immune dysfunction of C57BL/6 mice induced by low micronutrient supplementation. MATERIALS/METHODS: Female C57/BL/6 mice were fed a diet containing 7.5% of the recommended amount of micronutrients for a period of 12 wks (immunological assay) and 18 wks (survival test). For immunological assay, lymphocyte proliferation, cytokine regulation, and hepatic oxidative status were determined. RESLUTS: Pyc supplementation with 50 and $100mg{\cdot}kg^{-1}{\cdot}bw{\cdot}d^{-1}$ resulted in partial extension of the median survival time. Pyc supplementation led to increased T and B cell response against mitogens and recovery of an abnormal shift of cytokine pattern designated by the decreased secretion of Th1 cytokine and increased secretion of Th2 cytokine. Hepatic vitamin E level was significantly decreased by micronutrient deficiency, in accordance with increased hepatic lipid peroxidation level. However, Pyc supplementation resulted in a dose-dependent reduction of hepatic lipid peroxidation, which may result from restoration of hepatic vitamin E level. CONCLUSION: Findings of this study suggest that Pyc supplementation ameliorates premature death by restoring immune dysfunction, such as increasing lymphocyte proliferation and regulation of cytokine release from helper T cells, which may result from the antioxidative ability of Pyc.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.14 no.3
• /
• pp.87-95
• /
• 2005

The object of this study is to investigate the effect of joinability by using acoustic emission(AE) signals and doing a pattern recognition for weld heat affected zone(HAZ) in tensile testing. This study was carried out an SWS 490A high tension steel for electric shielded metal arc welding(SMAW), $CO_2$ gas arc welding and TIG welding. And correspondingly, the root openings are 3, 4 and 2.8mm. The results of the tensile test of weld HAZ come out electric shield arc welding $>\;CO_2$ gas arc welding > TIG welding in case of single welding. It is believed that this is a phenomenon where difference of its root opening or base metal thickness. Also, the technique of AE is ideally suited to study variables which control time and stress dependent fracture or damage process in metallic materials.

• Biomolecules & Therapeutics
• /
• v.11 no.1
• /
• pp.33-40
• /
• 2003

The present study was designed to investigate the effects of green tea extract (CUMC6335) and epigallocatechin gallate (EGCG) on secretion of catecholamines (CA) in the isolated perfused rat adrenal gland. ill the presence of CUMC6335 (100 $\mu\textrm{g}$/mL) into an adrenal vein for 60 min, CA secretory responses evoked by ACh(5.32 mM), high $K^+$ (56 mM) and Bay-K-8644 (10$\mu$M for 4 min) from the isolated perfused rat adrenal glands were greatly inhibited in a time-dependent fashion. However, EGCG (8 $\mu\textrm{g}$/mL) did not affect CA release evoked by ACh, high $K^+$ and Bay-K-8644. CUMC6335 itself did fail to affect basal catecholamine output. Taken together, these results demonstrate that CUMC6335 inhibits greatly CA secretion evoked by stimulation of cholinergic nicotinic receptors as well as by the direct membrane deplarization from the isolated perfused rat adrenal gland. It is felt that this inhibitory effect of CUMC6335 may be due to blocking action of the L-type dihydropyridine calcium channels in the rat adrenal medullary chromaffin cells, which is relevant to the cholinergic nicotinic blockade. It seems that there is a big difference in mode of action between CUMC6335 and EGCG.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.31 no.2
• /
• pp.35-39
• /
• 2015

The developmental responses of insects to temperature are important considerations in gaining a better understanding of their ecology and life histories. Temperature-dependent phenology models permit examination of the effects of temperature on the geographical distributions, population dynamics, and management of insects. Measurements of insect developmental and survival responses to temperature pose practical challenges that depend on the chosen modality, variability among individuals, and high mortality rates near the lower and upper threshold temperatures. Different temperature levels can significantly affect larval development of Eurema hecabe. The development of E. hecabe reared on leaves of Lespedeza cuneata was investigated at three temperature regimes (20, 25, and 30℃), a relative humidity of 60%, and a light:dark photoperiod of 14:10 h. The developmental time from larva to adult was 34.3, 20.6, and 17.9 d at temperatures of 20, 25, and 30℃, respectively. Pupal rate was 47.6%, 47.6%, and 61.9% at temperatures of 20, 25, and 30℃, respectively. The developmental threshold temperature estimated from larva to pupae was 8.1℃ with 381.7 degree-days. There is an increasing need for a standardized manual for rearing this butterfly species based on adequate knowledge of its ecology.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.14 no.1
• /
• pp.63-68
• /
• 2007

The response of silkworm, Bombyx mori L. to phytoecdysteroid (PE) when administered at different ages of $5^{th}$ instar was studied in the popular bivoltine ($CSR2{\times}CSR4$) and multi${\times}$bivoltine ($PM{\times}CSR2$) silkworm hybrids, reared on the Victory-1 variety of mulberry leaves. PE was administered to $5^{th}$ instar silkworm per os at a rate of $250{\mu}g$ per 100 larvae to different batches of silkworm at 0, 24, 48, 72, 96, 120, 144 hrs and at the onset of cocoon spinning when a few larvae were ripe. The larval and mounting duration, cocoon yield and cocoon characters were influenced by PE. The intensity of influence was dependent on the time of application. The larvae treated at the beginning of the instar, improved the economic traits significantly with a marginal increase in larval duration. In the larvae treated at the middle of the instar, larval duration was shortened remarkably but the economic traits were adversely affected. This particular treatment can become a good management strategy in the case of mulberry leaf shortage or disease incidence. In the larvae treated at the onset of cocoon spinning, the mounting duration was substantially reduced without much effect on the cocoon traits which would be a big benefit in commercial sericulture. The physiological significance of varied response of silkworm to PE administration is discussed.

• Journal of Pharmaceutical Investigation
• /
• v.35 no.2
• /
• pp.95-99
• /
• 2005

Mucoadhesive microspheres were prepared by interpolymer complexation of chitosan with poly(acrylic acid) (PAA) and solvent evaporation method to increase gastric residence time. The chitosan-PAA complex formation was confirmed by differential scanning calorimetry and swelling study. The DSC thermogram of chitosan-PAA microspheres showed two exothermic peaks for the decomposition of chitosan and PAA. The swelling ratio of the chitosan-PAA microspheres was dependent on the pH of the medium. The swelling ratio was higher at pH 2.0 than at neutral pH. The results indicated that the microspheres were formed by electrostatic interaction between the carboxyl groups of PAA and the amine groups of chitosan. The effect of various process parameters on the formation and morphology of microspheres was investigated. The best microspheres were obtained when 1.5% of the high molecular weight chitosan and 0.3% of PAA were used as an internal phase. The optimum internal phase volume was 7%. The com oil was used as the external phase of emulsion, and span 80 was used as the surfactant. The prepared microspheres had spherical shape.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.1
• /
• pp.132-138
• /
• 2007

Carbon nanotubes (CNTs) arc grown on Ni catalysts employing an inductively-coupled plasma chemical vapor deposition (ICP-CVD) method. The structural and field-emissive properties of the CNTs grown are characterized in terms of the substrate-bias applied. Characterization using the various techniques, such as field-omission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), Auger spectroscopy (AES), and Raman spectroscopy, shows that the structural properties of the CNTs, including their physical dimensions and crystal qualities, as well as the nature of vertical growth, are strongly dependent upon the application of substrate bias during CNT growth. It is for the first time observed that the provailing growth mechanism of CNTs, which is either due to tip-driven growth or based-on-catalyst growth, may be influenced by substrate biasing. It is also seen that negatively substrate-biasing would promote the vertical-alignment of the CNTs grown, compared to positively substrate-biasing. However, the CNTs grown under the positively-biased condition display a higher electron-emission capability than those grown under the negatively-biased condition or without any bias applied.

• Earthquakes and Structures
• /
• v.10 no.4
• /
• pp.867-891
• /
• 2016

This paper addresses numerically the behavior of steel structures under Fire-after-Earthquake (FAE) loading. The study is focused on a four-storey library building and takes into account the damage that is induced in structural members due to earthquake. The basic objective is the assessment of both the fire-behavior and the fire-resistance of the structure in the case where the structure is damaged due to earthquake. The combined FAE scenarios involve two different stages: during the first stage, the structure is subjected to the ground motion record, while in the second stage the fire occurs. Different time-acceleration records are examined, each scaled to multiple levels of the Peak Ground Acceleration (PGA) in order to represent more severe earthquakes with lower probability of occurrence. In order to study in a systematic manner the behavior of the structure for the various FAE scenarios, a two-dimensional beam finite element model is developed, using the non-linear finite element analysis code MSC-MARC. The fire resistance of the structure is determined using rotational limits based on the ductility of structural members that are subjected to fire. These limits are temperature dependent and take into account the level of the structural damage at the end of the earthquake and the effect of geometric initial imperfections of structural members.

• Wind and Structures
• /
• v.5 no.2_3_4
• /
• pp.277-290
• /
• 2002

A two dimensional discrete vortex method (DIVEX) has been developed at the Department of Aerospace Engineering, University of Glasgow, to predict unsteady and incompressible flow fields around closed bodies. The basis of the method is the discretisation of the vorticity field, rather than the velocity field, into a series of vortex particles that are free to move in the flow field that the particles collectively induce. This paper gives a brief description of the numerical implementation of DIVEX and presents the results of calculations on a recent suspension bridge deck section. The results from both the static and flutter analysis of the main deck in isolation are in good agreement with experimental data. A brief study of the effect of flow control vanes on the aeroelastic stability of the bridge is also presented and the results confirm previous analytical and experimental studies. The aeroelastic study is carried out firstly using aerodynamic derivatives extracted from the DIVEX simulations. These results are then assessed further by presenting results from full time-dependent aeroelastic solutions for the original deck and one of the vane cases. In general, the results show good qualitative and quantitative agreement with results from experimental data and demonstrate that DIVEX is a useful design tool in the field of wind engineering.