• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.262-270
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• 2007

Of the twelve lytic bacteriophages recovered from five different fermenting cucumber tanks that were inoculated with Pediococcus sp. LA0281, a lytic phage, ${\phi}ps05$, was characterized in the present study. The plaques were mostly clear and round-shaped on the lawn of starter strain, indicating lytic phage. Overall appearance indicated that it belongs to the Siphoviridae family or Bradley's group B1, with a small isometric head and a flexible noncontractile tail with swollen base plate. The average size was found to be 51.2 nm in head diameter and 11.6 nm wide ${\times}$ 129.6 nm long for the tail. The single-step growth kinetics curve showed that the eclipse and the latent period were 29 min and 34 min, respectively, and an average burst size was calculated to be 12 particles per infective center. The optimum proliferating temperature ($35^{\circ}C$) was slightly lower than that of cell growth ($35\;to\;40^{\circ}C$). The structural proteins revealed by SDS-PAGE consisted of one main protein of 33 kDa and three minor proteins of 85, 58, and 52 kDa. The phage genome was a linear double-stranded DNA without cohesive ends. Based on the single and double digestion patterns obtained by EcoRI, HindIII, and SalI, the physical map was constructed. The overall size of the phage genome was estimated to be 24.1 kb. The present report describes the presence of a lytic phage active against a commercial starter culture Pediococcus sp. LA0281 in cucumber fermentation, and a preliminary study characterizes the phage on bacterial successions in the process of starter-added cucumber fermentation.

• Journal of Plant Biology
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• v.37 no.2
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• pp.141-149
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• 1994

Levels of genetic diversity, population genetic structure, and gene flow in Hosta yingeri, a herbaceous perennial endemic to Taehuksan, Sohuksan, and Hong Islands, were investigated. Starch gel electrophoresis was conducted on leaves for 101 plants collected from three populations. Although the distribution of thespecies is restricted in the islands, it maintains high levels of genetic variatin; 64% of polymorphic loci in at least one population (Ps), the mean number of alleles per locus (Ap) of 1.92, and the mean effective number of alleles per locus (Aep) of 1.52. Overall, mean genetic diversity (Hep=0.250) was substantially higher than mean estimate for species with very similarlife history traits (0.102). Large populaton size, the persistence of multiple generations within populations, high fecundity, predominantly outcrossing breeding system, large size of pollinator visitation areas may be explanatory factors contributing the higher level of genetic diversity maintained within populations. Analysis of fixation indices showed an overall slight excess of heterozygotes (mean FIS=-0.066) relative to Hardy-Weinberg expectations, which may in part be due to the near self-incompatible breeding system in the species. Significant differences in allele frequencies among populaitns were found for 14 out of 16 polymorphic loci (P<0.05). Slightly more than 80% of the total variation in the species was common to all populations (GST=0.198). As expected, indirect estimate of the number of migrants per generation (Nm=0.45, calculated from mean GST) and nine private alleles found in the three populations indicate that gene movement among three isolated island populations was low.

• Journal of Chest Surgery
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• v.26 no.3
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• pp.214-218
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• 1993

Extensive lymphnode dissection combined with thoracic esophagectomy improved prognosis of esophageal cancer, but there is still high postoperative recurrence rate. The immunologic capacity of esophageal cancer patients is compromised by surgery and adjuvant chemotherapy. Therefore immunological therapy for esophageal cancer patients seems rational. We have adopted postoperative immunochemotherapy since 1988. From 1988 to 1992, 31 patients with thoracic esophageal cancer underwent esophagectomy and radical lymphnode dissection, and selected patient with early esophageal cancer and unfit for thoracotomy underwent transhiatal esophagectomy in Korea University Hospital. Mean age of patients was 56 years. There were 28 squamous cell cancers, 2 adenocarcinomas and one mixed tumor. There were 4 stage I, 3 stage II, 18 stage III, and 6 stage IV cases. There were no opeartive death. Postoperative complications included anastomotic leakage in 9%, pneumonia 3 %, cylothorax 3%, recurrent laryngeal neve paresis in 3% of all patients. Curative resection group[n=19] received immunotherapy. Noncurative resection group[n=12] received postoperative immunochemotherapy, including PS-K, CDDP, and 5-FU. Operative survivors were followed from 4 months to 5 years. There were 3 lost of follow-up. Actuarial survival rate is 79% to one year, 54% to two years and 27% to five years.In conclusion, an transthoracic esophagectomy combined with systematic lymph node dissection and postoperative immunochemotherapy could improve survival rate for esophageal cancer.

• Journal of the Korean Society of Food Culture
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• v.18 no.6
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• pp.515-526
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• 2003

The object of this study was to investigate the relationship between the eating habits of high(4th, 5th, 6th) grade elementary school students and parental behavior characteristics(affection, rational guidance, overprotect and neglect). The parenting behavior scale and demographic variables, eating habits and food frequency were administered to the subjects. In this investigation, the subjects were 396 boys and 337 girls in Chunju city in Korea, 50.1% of the mothers was in the age from 35 to 39 years and 57.8% of the mother had an occupation. Data were analyzed by using a SPSS PS package. Significant differences and correlation among variables were determined by the frequency, $x^2-test$ and pearson's correlation coefficient. Eating habits was significantly influenced by mother's employment status, but was not affected by the levels of mother's education and income. Parental behavior characteristics was significantly related to the children's snacks habits(p<0.05, p<0.01), but have no connection with dietary habits and the eating out. The survey revealed higher percentage of the children who had taken affectionate, reasonable and positively reinforced child care, answered they enjoy meals and the other groups answered they did not. Also frequency of having soup, green vegetables, fruits, dairy products had positive relationship with affective, reasonable rearing attitude, but negative relationship with neglective rearing attitude. And the survey showed children who were reared in overprotect had chocolate, candy and the like in large quantities.

• Korean journal of food and cookery science
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• v.13 no.2
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• pp.185-191
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• 1997

The effects of five hydrated emulsifiers with or without specified proteins (flour, egg) and/or polydextrose on the reduced-calorie cake as baked product model systems were compared. The small molecule amphiphiles (SMA) used were monoglycerides (MG), sorbitan monostearate (SMS), polysorbate (PS) 60, sucrose ester (SE) F7O, and SE Fl60. All flour batters with each emulsifier and supplements had similar low foam drainages (0.00∼1.03$m\ell$) indicating those systems were fairly stable in the presence of flour protein. The cake batter using starch instead of flour without egg and polydextrose and with some emulsifiers had relatively large amount of drainages (4.20∼5.87$m\ell$). When the egg and polydextrose were added to the blank cake batters using starch, foam drainages tended to show relatively low scores (0.13∼1.48$m\ell$) indicating the cake batter dispersion system is stabilized. Starch cakes made with SE F70 without egg or polydextrose(blank) unexpectedly had high volume index of 199.

• Journal of Chest Surgery
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• v.19 no.1
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• pp.116-121
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• 1986

Patients over 15 years of age who have undergone a surgical correction of a congenital cardiac malformation during period of January 1958 through January 1986 have been reviewed. During this period there were 3957 congenital cardiac lesions consisting of 2712 acyanotic and 1245 cyanotic cases. Among them, a total of 725 adults [18.3%] with a variety of congenital heart lesions, 548 acyanotic group and 177 cyanotic group were operated on. 372 patients were male and 252 patients were female. There were 280 patients under 20 years of age, 206 between 20-24 years, 102 between 25-29 years, 48 between 30-34 and 89 over 35 years. The most common defects were atrial septal defect which accounted for 207 cases [28.6%] and other common anomalies were VSD [140 cases, 19.3%], TOF [136 cases, 18.6%], PDA [120 cases, 16.6%] and PS [33 cases, 4.6%] in order of incidence. Overall operative mortality for this series was 3.6% [1.8% of a cyanotic group and 9.0% of cyanotic group] compared with 2.8% of total cases of congenital heart disease [acyanotic group 1.1% and cyanotic group 6.5%]. This reviewed series reveals the incidence of operable congenital heart defects appearing in any adult life and demonstrates that surgical repair can be accomplished with a satisfactory low mortality rate.

• Nuclear Engineering and Technology
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• v.53 no.8
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• pp.2661-2668
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• 2021

Gamma radiation shielding features for three series of binary alloys identified as (Pb-Sn), (Pb-Zn), and (Zn-Sn) have been investigated. The mass attenuation coefficients (µ/ρ) for the selected alloys were simulated using the MCNP-5 code in the energy range between 0.01 and 15 MeV. Moreover, the (µ/ρ) values were computed using WinXCOM database in the same energy range to validate the simulation results. Results reveal a good agreement between the simulated and computed values. The half value layer (HVL), mean free path (MFP), effective atomic number (Z_eff) and exposure buildup factor (EBF) were evaluated for the selected binary alloys. Results showed that the PS1, PZ1, and ZS2 alloys have the best shielding parameters and better than the commercially standard and available radiation shielding materials. Therefore, the investigated alloys can be used as effective radiation shielding materials against gamma ray with energies between 0.01 and 15 MeV.

• Journal of information and communication convergence engineering
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• v.10 no.2
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• pp.187-193
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• 2012

A 1 GHz CMOS fast-lock phase-locked loop (PLL) is proposed to support the quick wake-up time of mobile consumer electronic devices. The proposed fast-lock PLL consists of a conventional charge-pump PLL, a frequency-to-digital converter (FDC) to measure the frequency of the input reference clock, and a digital-to-analog converter (DAC) to generate the initial control voltage of a voltage-controlled oscillator (VCO). The initial control voltage of the VCO is driven toward a reference voltage that is determined by the frequency of the input reference clock in the initial mode. For the speedy measurement of the frequency of the reference clock, an FDC with a parallel architecture is proposed, and its architecture is similar to that of a flash analog-to-digital converter. In addition, the frequency-to-voltage converter used in the FDC is designed simply by utilizing current integrators. The circuits for the proposed fast-lock scheme are disabled in the normal operation mode except in the initial mode to reduce the power consumption. The proposed PLL was fabricated by using a 0.18-${\mu}m$ 1-poly 6-metal complementary metal-oxide semiconductor (CMOS) process with a 1.8 V supply. This PLL multiplies the frequency of the reference clock by 10 and generates the four-phase clock. The simulation results show a reduction of up to 40% in the worstcase PLL lock time over the device operating conditions. The root-mean-square (rms) jitter of the proposed PLL was measured as 2.94 ps at 1 GHz. The area and power consumption of the implemented PLL are $400{\times}450{\mu}m^2$ and 6 mW, respectively.

• Journal of the Korean Mathematical Society
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• v.57 no.3
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• pp.747-775
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• 2020

In this work we investigate the nonlocal elliptic equation with critical Hardy-Sobolev exponents as follows, $$(P)\;\{(-{\Delta}_p)^su={\lambda}{\mid}u{\mid}^{q-2}u+{\frac{{\mid}u{\mid}^{p{^*_s}(t)-2}u}{{\mid}x{\mid}^t}}{\hspace{10}}in\;{\Omega},\\u=0{\hspace{217}}in\;{\mathbb{R}}^N{\backslash}{\Omega},$$ where Ω ⊂ ℝ^N is an open bounded domain with Lipschitz boundary, 0 < s < 1, λ > 0 is a parameter, 0 < t < sp < N, 1 < q < p < p^∗_s where $p^*_s={\frac{N_p}{N-sp}}$, $p^*_s(t)={\frac{p(N-t)}{N-sp}}$, are the fractional critical Sobolev and Hardy-Sobolev exponents respectively. The fractional p-laplacian (-∆_p)^su with s ∈ (0, 1) is the nonlinear nonlocal operator defined on smooth functions by $\displaystyle(-{\Delta}_p)^su(x)=2{\lim_{{\epsilon}{\searrow}0}}\int{_{{\mathbb{R}}^N{\backslash}{B_{\epsilon}}}}\;\frac{{\mid}u(x)-u(y){\mid}^{p-2}(u(x)-u(y))}{{\mid}x-y{\mid}^{N+ps}}dy$, x ∈ ℝ^N. The main goal of this work is to show how the usual variational methods and some analysis techniques can be extended to deal with nonlocal problems involving Sobolev and Hardy nonlinearities. We also prove that for some α ∈ (0, 1), the weak solution to the problem (P) is in C^1,α(${\bar{\Omega}}$).

• Biomolecules & Therapeutics
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• v.28 no.2
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• pp.152-162
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• 2020

Cerebral ischemia exhibits a multiplicity of pathophysiological mechanisms. During ischemic stroke, the reactive oxygen species (ROS) concentration rises to a peak during reperfusion, possibly underlying neuronal death. Recombinant human erythropoietin (EPO) supplementation is one method of treating neurodegenerative disease by reducing the generation of ROS. We investigated the therapeutic effect of PEGylated EPO (P-EPO) on ischemic stroke. Mice were administered P-EPO (5,000 U/kg) via intravenous injection, and middle cerebral artery occlusion (MCAO) followed by reperfusion was performed to induce in vivo ischemic stroke. P-EPO ameliorated MCAO-induced neurological deficit and reduced behavioral disorder and the infarct area. Moreover, lipid peroxidation, expression of inflammatory proteins (cyclooxygenase-2 and inducible nitric oxide synthase), and cytokine levels in blood were reduced by the P-EPO treatment. In addition, higher activation of nuclear factor kappa B (NF-κB) was found in the brain after MCAO, but NF-κB activation was reduced in the P-EPO-injected group. Treatment with the NF-κB inhibitor PS-1145 (5 mg/kg) abolished the P-EPO-induced reduction of infarct volume, neuronal death, neuroinflammation, and oxidative stress. Moreover, P-EPO was more effective than EPO (5,000 U/kg) and similar to a tissue plasminogen activator (10 mg/kg). An in vitro study revealed that P-EPO (25, 50, and 100 U/mL) treatment protected against rotenone (100 nM)-induced neuronal loss, neuroinflammation, oxidative stress, and NF-κB activity. These results indicate that the administration of P-EPO exerted neuroprotective effects on cerebral ischemia damage through anti-oxidant and anti-inflammatory properties by inhibiting NF-κB activation.