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The phenotype or genomic enhanced breeding value (GEBV) of ultrasound intramuscular fat (UIMF) was used as the target trait to improve meat quality. The ZPLAN+ software was employed to calculate and compare the genetic gain and accuracy of each selection scenario. The first scenario reflected the current conventional selection program in which the selection index is composed of average daily gain (ADG), feed conversion ratio (FCR) and ultrasound backfat (UBF). In the second scenario, UIMF was added into the basic selection index as an indicator trait for meat quality. In scenario 3, UIMF was also incorporated into index; however, the GEBV was used instead of phenotype. In scenario 4 and 5, selection was based strictly on the GEBV, and UIMF was included in scenario 5. The results showed that the accuracies of scenario 3, 4 and 5, in which GEBV information was used, increased with increasing accuracy of the GEBV. Moreover, the trends of scenario 4 and 5 changed more rapidly relative to scenario 3. The addition of UIMF to the selection index had a positive effect on the genetic gain of ADG and FCR, but a negative effect on UBF. The addition of UIMF to the selection index led to improvement of other traits and to the overall meat quality, especially when genomic selection was applied.

Saposhnikovia divaricata, Peucedanum japonicum, and Glehnia littoralis of the family Umbelliferae, have long been used as traditional herbal medicine in Asian countries. This study is the first to compare and analyze the relationship between antimicrobial activity, antioxidant activity, and total polyphenol content of Saposhnikovia divaricata, Peucedanum japonicum, and Glehnia littoralis. The four fractions of hydro-methanol extract of these 3 plants were evaluated using the disc diffusion method to determine the minimum inhibitory concentration against 5 different bacterial strains. The ethyl acetate fraction was the most effective against the bacterial strains investigated. The 1,1-diphenyl-2-picryl-hydrazyl free radical scavenging activity was evaluated to measure antioxidant activity. The antioxidant activity of the ether and ethyl acetate fractions was in the order of Saposhnikovia divaricata>Peucedanum japonicum>Glehnia littoralis. The total polyphenol content of Saposhnikovia divaricata was greater than that of Peucedanum japonicum and Glehnia littoralis. Even though the 3 plants belong to the same family and are used for similar medical purposes, their antimicrobial activity, antioxidant activity, and total polyphenol content was different. This study would help researchers to uncover the critical aspects of the activities possessed by plants.

This study was conducted to estimate the genetic parameters for pork belly traits and muscles in Yorkshire pigs. Each pork belly was cut into nine parts perpendicular to the thoracic vertebrae (6th to 14th). Traits of belly muscles including the deep pectoral, latissimus dorsi, cutaneous trunci, rectus abdominis, external and internal abdominal oblique from 382 purebred pigs were recorded and analyzed using SAS Package (9.1) and Derivative-free restricted maximum likelihood methods. Heritability estimates for belly traits ranged from 0.27 to 0.49, while they were 0.12 to 0.66 for belly muscles. Moderate to high heritability estimates were noted in belly weight (0.33), belly length (0.28), and belly width (0.49). In belly muscles, the latissimus dorsi and deep pectoral, which are located only in the 6th to 9th vertebrae sections, were found to have heritability estimates ranging from 0.21 to 0.29 and 0.23 to 0.35, respectively. Strong heritability estimates were observed in the 7th to 13th sections of cutaneous trunci muscle ranging from 0.42 to 0.66. Genetic correlations of latissimus dorsi m. with belly length were positive (0.50), while cutaneous trunci m. with belly weight also revealed a positive relationship that ranged from 0.35 to 0.47. The estimated genetic parameters indicate that belly weight can be improved by genetic selection. Differences in the levels of heritability occurred among various parameters of Yorkshire pork belly, which should be considered when performing selection to improve pork belly quality. Moreover, these results can provide valuable information that can be used as the basis for further investigations to improve pork belly.

Data collected from 690 purebred Duroc pigs from 2009 to 2012 were used to estimate the heritability, and genetic and phenotypic correlations between production and meat quality traits. Variance components were obtained through the restricted maximum likelihood procedure using Wombat and SAS version 9.0. Animals were raised under the same management in five different breeding farms. The average daily gain, loin muscle area (LMA), backfat thickness (BF), and lean percent (LP) were measured as production traits. Meat quality traits included pH, cooking loss, lightness (L*), redness (a*), yellowness (b*), marbling score (MS), moisture content (MC), water holding capacity (WHC), and shear force. The results showed that the heritability estimates for meat quality traits varied largely from 0.19 to 0.79. Production traits were moderate to highly heritable from 0.41 to 0.73. Genotypically, the BF was positively correlated (p

Intramuscular fat (IMF) in cattle is an important component of traits that influence meat quality. We measured carcass characteristics and gene expression in Korean steers to clarify the molecular mechanism(s) underlying IMF deposition in LM tissue by determining the correlation between IMF content and gene expression abundance and by developing models to predict IMF content using gene expression abundance. The deposition of IMF is determined by a balance between fat deposition and fat removal in the LM. We measured mRNA abundance of lipid metabolic genes including lipogenesis [acetyl CoA carboxylase (ACC), fatty acid synthase (FASN)], fatty lipid uptake [lipoprotein lipase (LPL), fatty acid translocase (CD36), fatty acid transport protein 1 (FATP1)], fatty acid esterification [glycerol-3-phosphate acyltransferase 1 (GPAT1), acylglycerol phosphate acyltransferase 1 (AGPAT1), diacylglycerol acyltransferase 1 (DGAT1), DGAT2], lipolysis [adipose triglyceride lipase (ATGL), hormone-sensitive lipase (HSL), monoglyceride lipase (MGL)], and fatty acid oxidation [carnitine palmitoyl transferase 1B, very long-chain acyl-CoA dehydrogenase (VLCAD), medium-chain acyl-CoA dehydrogenase (MCAD)] in the LM. The mRNA abundance of the GPAT1 gene showed the greatest correlation (r = 0.74; P < 0.001) with IMF content among 9 fat deposition genes. The gene expression abundance of other fat deposition genes including ACC, FASN, LPL, CD36, FATP1, AGPAT1, DGAT1, and DGAT2 also exhibited significant positive correlations (P < 0.05) with IMF content in the LM. Conversely, ATGL mRNA abundance showed the greatest negative correlation (r = -0.68; P < 0.001) with IMF content in the LM among 6 fat removal genes. The expression of other fat removal genes including MGL, VLCAD, and MCAD showed significant negative correlations (P < 0.05) with IMF content. Our findings show that the combined effects of increases in lipogenesis, fatty acid uptake, fatty acid esterification, and of decreases in lipolysis and fatty acid oxidation contribute to increasing IMF deposition in Korean steers. The multiple regression analysis revealed that the mRNA abundance of the GPAT1 gene in the LM was the first major variable predicting IMF content (54%) among 15 lipid metabolic genes. The second was mRNA abundance of ATGL (11%). In conclusion, these results suggest that GPAT1 and ATGL genes could be used as genetic markers to predict IMF deposition in the LM.

We investigated the resistance of murine norovirus (MNV) and coliphage MS2, a culturable human norovirus surrogate, to temperature, salt, and pH. Virus inactivation was measured by plaque, real-time TaqMan reverse transcription (RT) PCR, and long-template RT-PCR assays. Both MNV and MS2 were rapidly inactivated at temperatures above 60°C. Similarly, MNV tolerated low salt concentrations (0.3% NaCl) to a greater degree than high salt concentrations (3.3 to 6.3% NaCl). MNV was relatively resistant to strong acidic conditions (pH 2) and was more tolerant of slightly acidic (pH 4) or neutral (pH 7) conditions. In contrast, MS2 was resistant to high salinity. Overall, temperature had a greater effect on infectivity than salt or low pH. Additionally, temperature and low pH had a synergistic effect on MNV infectivity. Both real-time and long-template RT-PCR assays significantly underestimated the inactivation by temperature, salt, and pH. The inactivation kinetics of both MNV and MS2 under various environmental conditions gave a good fit by the Weibull model (R² > 0.9). This study suggests both the capacity of infectious human norovirus to persist in the face of various environmental conditions and its sensitivity to high temperatures, which may provide a mechanism of protection against this virus.

To prevent oxidative quality changes, a few selected antioxidants, ascorbic acid, or an ascorbic acid plus α-tocopherol combination were electrostati- cally sprayed on the surface of ground beef patties. Col- or, metmyoglobin, oxidation-reduction potential, lipid oxidation, and volatiles of the samples were determined during the 8 d of aerobic storage. Spraying of ascorbic acid at 500 mg/kg was the most effective in controlling discoloration of ground beef. Spraying of ascorbic acid at 500 mg/kg was also effective in reducing 2-thiobar- bituric acid-reactive substances and volatile aldehydes such as hexanal and heptanal related to lipid oxidation. Spraying of phenolic antioxidants such as tocopherol, sesamol, or rosemary oleoresin showed significant (P < 0.05) antioxidant effects, but had no effects (P < 0.05) in stabilizing the color of ground beef. Sesamol at 100 mg/kg showed the most potent antioxidant activities among the antioxidants, and its antioxidant effect was as strong as that of 500 mg/kg of ascorbic acid. It was concluded that electrostatic spray of ascorbic acid on the surface of ground beef at 500 mg/kg was an efficient and economical way to prevent both lipid oxidation and color changes in ground beef.

The water quality of Lake Shihwa had been rapidly deteriorating since 1994 due to wastewater input from the watersheds, limited water circulation and the lack of a wastewater treatment policy. In 2000, the government decided to open the tidal embankment and make a comprehensive management plan to improve the water quality, especially inflowing stream water around Shihwa and Banwol industrial complex. However, the water quality and microbial community have not as yet been fully evaluated. The purpose of this study is to investigate the influent water quality around the industrial area based on chemical and biological analysis, and collected surface water sample from the Siheung Stream, up-stream to down-stream through the industrial complex, Samples were collected in July 2009. The results show that the downstream site near the industrial complex had higher concentrations of heavy metals (Cu, Mn, Fe, Mg, and Zn) and organic matter than upstream sites. A combination of DGGE (Denaturing Gradient Gel Electrophoresis) gels, lists of K-WQI (Korean Water Quality Index), cluster analysis, MDS (Multi-Dimensional Scaling) and PCA (Principal Component Analysis) has demonstrated clear clustering between Siheung stream 3 and 4 and with a high similarity and detected metal reducing bacteria (Shewanella spp.) and biodegrading bacteria (Acinetobacter spp.). These results suggest that use of both chemical and microbiological marker would be useful to fully evaluate the water quality.

Summary Pigmentation genes such as TYR (tyrosinase), TYRP1 (tyrosinase-related protein 1), DCT (previously TYRP2, or tyrosinase-related protein 2), ASIP (agouti) and MC1R (melanocortin receptor 1) play a major role in cattle coat colour. To understand the genotypic profile underlying coat colour in native Korean Hanwoo cattle and Angus black cattle, portions of the above-mentioned genes were amplified. Sequence analysis revealed variation in the TYRP1 (exon 5) and MC1R genes. Restriction enzyme analysis of these two genes could distinguish between different colours of Hanwoo cattle. Quantitative estimates of melanin and eumelanin in hair from three different-coloured Hanwoo phenotypes and Angus black showed significant differences at the breed and phenotypic levels. Finally, sequence variants in MC1R were associated with total melanin and eumelanin in breeds as well as in Hanwoo phenotypes.

This study was conducted to develop a traceability system for systematic animal identifi- cation to increase efficiency of animal production, post production and processing to ensure that quality and sanitary meat products reach the consumers of the entire country. The new animal identification traceability system was designed for easy management, data collection and storage considering bar code, registration number and farm number.Specifically the system aimed 1) To provide standard radio frequency technology identification (RF-ID) for livestock management, standard of ear tag, microchip and ear tag identification equipment, 2) To guarantee meat product label thereby safeguarding the consumers 3) To give incentives to farmers for producing quality meat products and 4) To provide unified system for national livestock management.Results of the research which started in July 2003 which was used by several farmers’ cooperatives and Department Store revealed the feasibility of using the RF-ID system although much will be done to conform to global nomenclatures.

This paper reports a high power 60 GHz push–push oscillator fabricated using 0.12 μm GaAs metamorphic high electron-mobility transistors. By combining high-power metamorphic high electron mobility transistor (MHEMT) optimized for millimeter-wave operation and push–push technique, the oscillator achieved 7.4 dBm of output power at 59 GHz with 37 dBc fundamental frequency suppression. To the knowledge of the authors, this is the first monolithic push–push oscillator at V-band fabricated using MHEMT technology. Also, the 7.4 dBm of output power is the largest for any oscillators based on MHEMT in this frequency range, and compares well to the result obtained from mature GaAs PHEMT technology. The results demonstrate the application of high power MHEMT for cost effective millimeter-wave commercial applications. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 609–612, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22203

This study was conducted to observe the effect of the growth hormone (GH)/insulin-like growth factor-1(/IGF-1) axis on leptin and feed intake of 15 Holstein calves in three groups. One group was fed a normal diet (control); the second group, with high nutrition after low feeding with bovine growth hormone (bGH), and a third group, without high nutrition (saline) after low feeding. Each group was intramuscularly (i.m.) injected daily with bovine GH (200 µg kg-1 d-1) or saline solution for 10 d. No significant differences were found in the concentrations of plasma leptin over time for a 24-h period. Plasma leptin was decreased in both saline and GH groups during low and high nutrition regimes, respectively, while IGF-1 levels increased for both nutrition regimes (P < 0.05). With GH treatment during refeeding periods (P < 0.05), leptin levels increased and feed intake decreased; however, the plasma leptin levels slightly decreased with GH treatment during low feeding periods. The plasma IGF-1 concentration increased with GH administration during normal and refeeding periods (P < 0.05). These results indicate that the response of plasma leptin levels to GH varied according to the nutritional condition. In addition, the GH/IGF-1-induced increase in leptin production during the refeeding period may serve as a signal to reduce the feed intake or to increase dramatically after feed restriction in cattle. Key words: Feed intake, growth hormone, leptin, insulin-like growth factor-1, Holstein calves

This study was conducted to determine the characteristics of IGFBPs in plasma of steers, and to profile the relationship between growth and plasma IGF-1 and IGFBPs with aging in Holstein steers. Four blots of IGFBP at molecular weights of 38-43, 34, 29-32 and 24 kDa bands were detected by western ligand blot assay using 125 I-IGF-1. On the basis of immunoblotting with anti-bovine IGFBP-2 and -3 antiserums, we observed the band for IGFBP-2 at approximately 34 kDa, and the IGFBP-3 band was detected at 38-43 kDa and 34 kDa in adult steers and calves. The IGFBP-3 antiserum used on the blots exhibited significant cross-reactivity with 34 kDa IGFBP-2. Furthermore, the 38-43 kDa IGFBP-3 bands were reduced to a 36 kDa band after deglycosylation, whereas the 34 kDa IGFBP-2 was intact. The plasma IGF-1, IGFBP-3 and other IGFBPs showed stability throughout a whole day. The change in live weight was found to be positively correlated to the plasma IGF-1 concentration (r = 0.6801, n = 64, p

The research described in this paper concerns the characterisation of polyurethane and polystyrene foam for use as shock absorbing filling materials in impact limiters for nuclear transport packages. For a comparatively small cylindrical transport package the mechanical properties of the foam material in compression tests, a preliminary determination of the best foam density and its co-relation with other material properties, appropriate selection of polyurethane and polystyrene from the relation between the reaction force due to the drop impact and their compression characteristic properties are discussed.

The purpose of this paper is to perform a thermal analysis of a spent fuel storage cask in order to predict the maximum concrete and fuel cladding temperatures. Thermal analyses have been carried out for a storage cask under normal, off-normal and accident conditions. The environmental temperature is assumed to be 27°C under the normal condition. The off-normal condition has an environmental temperature of 40°C. An additional off-normal condition is considered as a partial blockage of the air inlet ducts. Four of the eight inlet ducts are assumed to be completely blocked. The accident condition is defined as a 100% blockage of air inlet ducts. The storage cask is designed to store 24 PWR spent fuel assemblies with a burn-up of 55,000 MWD/MTU and a cooling time of 7 years. The decay heat load from the 24 PWR assemblies is 25.2 kW. Thermal analyses of the ventilation system have been carried out for the determination of the optimum duct size and shape. The finite-volume computational fluid dynamics...

Radioactive isotopes must be safely transported from the production centre to the point of use. The shipping package to safely transport radioactive isotopes should be able to withstand the conditions prescribed by law. In the field of nuclear medicine, radioactive isotopes are used in liquid or capsule form. A Type A package, which is used to transport liquid radioactive materials, should have a containment system comprising a primary inner and a secondary outer containment or it should be provided with a sufficiently absorbent material to absorb twice the volume of the liquid contents. Hospitals prefer to use not only convenient but also reusable packages. In this work the free absorbency of absorbents for use in a Type A package for transporting liquid radioactive isotopes was estimated. Among the absorbent materials studied, it was found that in the case of a liquid with 0.4% NaOH, the free absorbency of the melamine foam was best at 91 g g-1. In the case of a liquid with 0.9% Na, the free abs...

The production of metal strip with uniform thickness and flatness are two important problems associated thin strip rolling. The thickness and flatness of strip are affected by the flattening of contact surface between strip and roll, the elastic recovery and the bending of roll. Especially, the flatness of the strip is greatly affected by bending deflection of roll. The roll must be designed considered the elastic deformation of roll. This study describes the measurement of thickness and flatness of strip and shows the crown roll for producing flat strip. But it is difficult to produce the crown roller. The cross rolling that is a simple method which can produce the flat strip is introduced and it is found the optimal cross angle for improvement of flatness of plate. These problems are solved by the MARC code on the basis of elastic-plastic material and the updated Lagrangian formulation.

Water-dispersible carboxymethylcellulose acetate butyrate (CMCAB) has been shown to improve flow and levelling, and reduce cratering, picture framing, and other defects in water-borne paints.

Carcass characteristics of 241 crossbred pigs (Korean wild boars × Landrace sows) were analyzed to examine variations in fasted body weight (FASTWT), carcass weight (CARCWT), dressing percentage (DP), back fat thickness (BFT) and longissimus muscle weight (LMW), and to estimate genetic and phenotypic parameters using three different slaughter-end points. Covariates in the least squares full sib model were slaughter age, fasted body weight and back fat thickness of the carcass. Coefficient of variation was highest for BFT followed by LMW, CARCWT, FASTWT and DP in magnitude. Regressions of three covariates on traits were all linear. However, slaughter age was not significant as a linear covariate for five traits while FASTWT was significant for CARCWT and LMW and BFT was significant for all remaining traits. Genetic and phenotypic variation was considerably reduced by regressing FASTWT or BFT in the model. Heritability estimates of FASTWT, CARCWT, DP and BFT were 0.68, 0.61, 0.11 and 0.49, respectively, using slaughter age as covariate (model 1). Those of CARCWT, DP, BFT and LMW were 0.15, 0.15, 0.30 and 0.11, respectively, using FASTWT as covariate (model 2). Heritability estimates of the traits using LMW as covariate (model 3) were similar to the estimates from Model 1 except that the estimate of CARCWT was reduced to 0.39. Genetic or phenotypic correlations among FASTWT, CARCWT and BFT were all positive and moderate to high. Those between BFT and LMW were also positive and low to moderate. However, genetic and phenotypic correlations between DP and CARCWT were positive while those between DP and FASTWT were negative. It was suggested from this study that differences in carcass yield traits be determined using slaughter age or back fat thickness as slaughter-end point and carcass quality traits using fasted body weight as slaughter-end point. (Asian-Aust. J. Anim. Sci. 2002. Vol 15, No. 8 : 1080-1084)

New approaches for assessment of lymphedema using ultrasonography (US) have been introduced recently and are reported to be reliable and simple. Ultrasonography provides detailed information about physical properties of the tissue in addition to volume and size. There have been only limited studies comparing bioimpedance analysis (BIA), US, and circumferential measurement (CM), which is considered a standard measurement. The aim of this study was to determine the relationship between US, BIA, and CM. Twenty-eight patients with lymphedema after breast cancer surgery underwent BIA, US, and CM. Impedance, which reflects the amount of extracellular fluid, was measured with 1 kHz frequency in affected and unaffected arms. Circumferences were measured at 10cm proximal and distal to the elbow and a truncated cone method used to calculate estimated volumes for upper arm and forearm. We found that interlimb forearm subcutis thickness differences measured by US were highly correlated with CM measurements and that interlimb upper arm subcutis thickness differences measured by US were moderately correlated with CM measurements and BIA ratios. However, the interlimb ratio of compressibility measured by US showed no or only weak correlation with impedance measurements and circumferential measurements. Our results also show that compressibility measured by US could not be predicted from BIA or CM measurements despite a high degree of concordance among subcutis thickness measured by US, CM, and BIA.

The molecular dimensions and melt rheology of a thermotropic all-aromatic liquid crystalline polyester (TLCP) composed of p-hydroxy benzoic acid, hydroquinone, terephthalic acid, and 2,4-naphthalenedicarboxylic acid is examined. The Mark–Houwink exponent (α) of 0.95 is estimated for the TLCP. The persistence length estimated from molecular weight (M) and intrinsic viscosity ([η]) data using the Bohdanecky–Bushin equation is about 95 A, whereas that estimated from light scattering data is 117 A. These persistence lengths and the observed α value, both higher than those for flexible polymers, suggest that the present TLCP is a semirigid polymer. The zero shear melt viscosity (η0) varies with approximately M6 for molecular weight M > 3 × 104 g/mol; below this molecular weight, η0 varies almost linearly with M. Widely different entanglement molecular weights (Me) are predicted, depending on the method used; the plateau modulus estimates Me of about 8 × 105 g/mol, whereas the ratio of mean square end-to-end distance and molecular weight (〈R2〉0/M) predicts Me's either too small (0.33 g/mol) or too large (2.5 × 106 g/mol), depending on the theory used. Although the change in the molecular weight dependency of melt viscosity appears to be associated with the onset of entanglement coupling of the semirigid molecules, its origin needs further investigation. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2378–2389, 2001

We report an ultrastructural study of the morphological changes in cells of the marine dinoflagellate Pyrocystis noctiluca Murray, which correlate with its vertical migration pattern. Cells alternate between a large, highly vacuolated, positively buoyant, vegetative cyst surrounded by a dinosporin-containing wall and a smaller, more compact, negatively buoyant, cellulose-bounded cell. The cyst wall is composed of two layers: a thin smooth outer layer, thought to be composed of dinosporin, and a thick inner layer that likely to be cellulosic. One or two thecate cells are formed from within the cysts. Thecate cells are smaller, more compact and contain many small translucent bodies. They are surrounded by a typical dinoflagellate amphiesmal layer composed of membranes and cellulose plates. The amphiesmal layer appears only in recently divided cells and exists for only one night. By the following day, the cellulose wall has been replaced by a new dinosporin wall synthesized from beneath the cellulose thecal layer. The cyst stage is suggested as being optimized for photosynthesis, whereas the compact, negatively buoyant, thecate form is thought to allow nutrient uptake in deeper waters. Vertical migration in this species is thus correlated with the presence of dinosporin wall during most of its stay in the upper waters, alternating with a brief thecate wall in deeper nutrient-rich waters. This is the first report correlating dinoflagellate vertical migration with changes in cell-wall composition.

This paper is concerned with a new architecture of an optimized FCM-based interval type-2 fuzzy neural network classifier developed with aid of Fuzzy C-Means (FCM) clustering and Particle Swarm Optimization (PSO). The premise part of the rules of this architecture is realized by two FCM clustering algorithms. These FCM clustering algorithms run for several values of the fuzzification coefficient subsequently resulting in interval type-2 membership functions. In the consequent part of the rules, the coefficients of a linear function are optimized by using a Back Propagation (BP) algorithm. The design parameters including the learning rate and the momentum term of BP as well as the fuzzification coefficients of the FCM are optimized by means of the PSO. The proposed classifier is applied to several machine learning data, and the obtained results are compared with those produced by other classifiers reported in the literature.

This paper is concerned with a growing rule-based fuzzy model and its design realized with the aid of fuzzy clustering. The objective of this study is to develop a new design methodology concerning incremental fuzzy rules formed through fuzzy clustering. The proposed model consists of three functional components : (a) The premise part of the fuzzy rules involves membership functions designed with the aid of the Fuzzy C-Means (FCM) clustering algorithm. (b) The consequent part comprises local models (linear functions). The parameters of the local models are estimated by running a Weighted Least Square Estimation (WLSE). (c) The process of rule growth in the growing part is concerned with a refinement of the model where a selected rule is split into two or more specialized rules providing a better insight into the system. These new rules are formed with the aid of a so-called context-based Fuzzy C-Means (C-FCM) clustering. The effectiveness of the proposed rule-based model is discussed and illustrated with the aid of some numeric studies including both synthetic and machine learning data.

Hypoxia-inducible factor-1α (HIF-1α) is a transcription factor that has a central role in the regulation of tumour metabolism under hypoxic conditions. HIF-1α stimulates glycolytic energy production and promotes tumour growth. Sirtuins are NAD(+)-dependent protein deacetylases that regulate cellular metabolism in response to stress; however, their involvement in the hypoxic response remains unclear. In this study, it is shown that SIRT2-mediated deacetylation of HIF-1α regulates its stability in tumour cells. SIRT2 overexpression destabilized HIF-1α under hypoxic conditions, whereas HIF-1α protein levels were high in SIRT2-deficient cells. SIRT2 directly interacted with HIF-1α and deacetylated Lys709 of HIF-1α. Deacetylation of HIF-1α by SIRT2 resulted in increased binding affinity for prolyl hydroxylase 2, a key regulator of HIF-1α stability, and increased HIF-1α hydroxylation and ubiquitination. Moreover, a pharmacological agent that increased the intracellular NAD(+)/NADH ratio led to the degradation of HIF-1α by increasing SIRT2-mediated deacetylation and subsequent hydroxylation. These findings suggest that SIRT2-mediated HIF-1α deacetylation is critical for the destablization of HIF-1α and the hypoxic response of tumour cells.

Si δ‐doped AlxGa1−xAs structures grown by metalorganic chemical vapor deposition have been studied by capacitance‐voltage (C‐V) measurements against temperature and frequency. The potential lowering due to the ionized DX centers is responsible for hysteresis and abnormal phenomena in C‐V curves at low temperatures. Two electron‐accumulation peaks are observed in C‐V profiles measured in the temperature range of 200–300 K. One is related to the occupancy of localized DX centers, and the other is related to the two‐dimensional electron gas at the planar layer of dopants. The apparent C‐V profile, which is widely used to determine the dopant distribution, also depends on the measuring frequency. This behavior is interpreted as an artifact caused by the emission kinetics of the DX centers localized in the dopant plane.

1 School of Electrical Engineering and Computer Science, Seoul National University, Republic of Korea San 56-1 Shillim-dong Gwanak-gu Seoul 151-742, Republic of Korea Phone: +82-2-877-0298, Fax: +82-2-887-6575, E-mail: elengine@snu.ac.kr 2 Semiconductor Business, Samsung Electronics Co., Ltd, Suwon, 443-743, Republic of Korea 3 School of Electronic and Electrical Engineering, Hongik University, Seoul 121-791, Korea

Intramuscular fat (IMF) in cattle is an important component of traits that influence meat quality. We measured carcass characteristics and gene expression in Korean steers to clarify the molecular mechanism(s) underlying IMF deposition in LM tissue by determining the correlation between IMF content and gene expression abundance and by developing models to predict IMF content using gene expression abundance. The deposition of IMF is determined by a balance between fat deposition and fat removal in the LM. We measured mRNA abundance of lipid metabolic genes including lipogenesis [acetyl CoA carboxylase (ACC), fatty acid synthase (FASN)], fatty lipid uptake [lipoprotein lipase (LPL), fatty acid translocase (CD36), fatty acid transport protein 1 (FATP1)], fatty acid esterification [glycerol-3-phosphate acyltransferase 1 (GPAT1), acylglycerol phosphate acyltransferase 1 (AGPAT1), diacylglycerol acyltransferase 1 (DGAT1), DGAT2], lipolysis [adipose triglyceride lipase (ATGL), hormone-sensitive lipase (HSL), monoglyceride lipase (MGL)], and fatty acid oxidation [carnitine palmitoyl transferase 1B, very long-chain acyl-CoA dehydrogenase (VLCAD), medium-chain acyl-CoA dehydrogenase (MCAD)] in the LM. The mRNA abundance of the GPAT1 gene showed the greatest correlation (r = 0.74; P0.001) with IMF content among 9 fat deposition genes. The gene expression abundance of other fat deposition genes including ACC, FASN, LPL, CD36, FATP1, AGPAT1, DGAT1, and DGAT2 also exhibited significant positive correlations (P0.05) with IMF content in the LM. Conversely, ATGL mRNA abundance showed the greatest negative correlation (r = -0.68; P0.001) with IMF content in the LM among 6 fat removal genes. The expression of other fat removal genes including MGL, VLCAD, and MCAD showed significant negative correlations (P0.05) with IMF content. Our findings show that the combined effects of increases in lipogenesis, fatty acid uptake, fatty acid esterification, and of decreases in lipolysis and fatty acid oxidation contribute to increasing IMF deposition in Korean steers. The multiple regression analysis revealed that the mRNA abundance of the GPAT1 gene in the LM was the first major variable predicting IMF content (54%) among 15 lipid metabolic genes. The second was mRNA abundance of ATGL (11%). In conclusion, these results suggest that GPAT1 and ATGL genes could be used as genetic markers to predict IMF deposition in the LM.

AlGaN/GaN heterostructures have very superior material properties such as high breakdown field and high saturation current. Especially, AlGaN/GaN HEMTs have received much attention for next-generation high-frequency and high-power devices, particularly at high temperature and voltage operation [1]. Although significant progresses have been made in the past few years, additional efforts are needed in regard to current collapse effects and reliability issues [2]. To reduce current collapse, proper surface passivation is needed in AlGaN/GaN HEMTs [3]. Moreover, N2 plasma pretreatment has been recently reported to supperssion current collapse prior to the SiN passivation [3]-[5]. In this study, we tried to use SiN prepassivation for additional effects; preventing nitrogen desorption at the GaN surface during high temperature ohmic alloy and early protection of surface open to the process flow. Furthermore, this work focuses on the in situ N2 plasma treatment just prior to the SiN prepassivation to further mitigate current collapse.