• Bulletin of the Korean Mathematical Society
• /
• v.58 no.2
• /
• pp.497-505
• /
• 2021

Let R → S be a ring homomorphism. The relations of Gorenstein projective dimension with respect to a semidualizing module of homologically bounded complexes between U ⊗LR X and X are considered, where X is an R-complex and U is an S-complex. Some sufficient conditions are given under which the equality ${\mathcal{GP}}_{\tilde{C}}-pd_S(S{\otimes}{L \atop R}X)={\mathcal{GP}}_C-pd_R(X)$ holds. As an application it is shown that the Auslander-Buchsbaum formula holds for GC-projective dimension.

• Bulletin of the Korean Chemical Society
• /
• v.28 no.10
• /
• pp.1746-1750
• /
• 2007

The second-order scattering (SOS) phenomenon of the interaction of Pd nanoparticles with protein was reported and a simple, sensitive, palladium nanoparticle-based assay for trace amount of protein with SOS technique was developed. The SOS intensities were significantly enhanced due to the interaction of Pd nanoparticles with bovine serum albumin (BSA) or human serum albumin (HSA) at pH 3.5 or 4.0, respectively. The maximum SOS peak appeared at 260/520 nm (λex/λem). The optimal experiment conditions, affecting factors and the influence of some coexisting substances were checked. The SOS intensity increased proportionally with the increase of Pd concentration below 3.0 × 10?5 mol·L?1, while declined gradually above 4.0 × 10?5 mol·L?1. BSA within the range of 0.01-2.6 μg·mL?1 and HSA of 0.01-1.7 μg·mL?1 can be detected with this method and the detection limits were 2.3 and 11.2 ng·mL?1, respectively. The method was successfully applied to the quantitative detection of total protein content in human serum samples with the maximum relative standard deviation (RSD) lower than 2.6% and the recoveries over the range of 99.5-100.5%.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.11
• /
• pp.1819-1826
• /
• 2015

Poly(ε-ʟ-lysine) (ε-PL) is a novel bioactive polymer secreted by filamentous bacteria. Owing to lack of a genetic system for most ε-PL-producing strains, very little research on enhancing ε-PL biosynthesis by genetic manipulation has been reported. In this study, an effective genetic system was established via intergeneric conjugal transfer for Streptomyces albulus PD-1, a famous ε-PL-producing strain. Using the established genetic system, the Vitreoscilla hemoglobin (VHb) gene was integrated into the chromosome of S. albulus PD-1 to alleviate oxygen limitation and to enhance the biosynthesis of ε-PL in submerged fermentation. Ultimately, the production of ε-PL increased from 22.7 g/l to 34.2 g/l after fed-batch culture in a 5 L bioreactor. Determination of the oxygen uptake rate, transcriptional level of ε-PL synthetase gene, and ATP level unveiled that the expression of VHb in S. albulus PD-1 enhanced ε-PL biosynthesis by improving respiration and ATP supply. To the best of our knowledge, this is the first report on enhancing ε-PL production by chromosomal integration of the VHb gene in an ε-PL-producing strain, and it will open a new avenue for ε-PL production.

• Journal of Korean Vacuum Science & Technology
• /
• v.5 no.2
• /
• pp.33-37
• /
• 2001

We measured x-ray magnetic circular dichroism of Co films on Pd(111) surface with and without Pd capping layer at the Co L$_2$,$_3$ edges. Perpendicular magnetization and orbital-moment enhancement are induced by the capping layer. The increase of perpendicular magnetic anisotropy induced by capping layer is considered to result from the increase of surface anisotropy due to the hybridization at the surface.

• Journal of Technologic Dentistry
• /
• v.23 no.1
• /
• pp.21-30
• /
• 2001

For biomedical applications. Ti-X%Zr-Y%Pd(X: $10{\sim}20$, Y:0.2 or 0.4) based alloys not containing harmful Al and V were newly designed, and polarization curves for their alloys were measured at $37^{\circ}C$ in 5% HCl solution in order to understand effects of Zr on the corrosion. From the results of anodic polarization behavior, it was found that the corrosion resistance increased with increasing Zr content. The results show their potential to develope Ti-based alloys for biomedical materials. The Ti-20%Zr-0.2%Pd alloy shows excellent corrosion resistance and was superior to those of the Ti. Ti-6%Al-4%V ELI alloy, Co-30%Cr-6%Mo alloy and STS 316L stainless steel.

• Nuclear Engineering and Technology
• /
• v.53 no.3
• /
• pp.894-900
• /
• 2021

This paper examines sorption of Pd(II) onto illite, MX-80 bentonite, and Queenston shale in Na-Ca-Cl solutions of varying ionic strength (IS) from 0.01 to 6.0 mol/L (M) and pH_c ranging from 3 to 9 under atmospheric conditions. A 2-site protolysis non-electrostatic surface complexation and cation exchange model was applied to the Pd sorption onto illite and MX-80 using PHREEQC, and the model results were compared to the experimental ones obtained in this work. Surface complexation and cation exchange constants were estimated for both illite and MX-80 through the optimization process to bring the predicted distribution coefficients from the model into alignment with the experimentally derived values. These optimized surface complexation constants were compared to existing linear free energy relationships (LFER).

• Journal of Microbiology and Biotechnology
• /
• v.26 no.7
• /
• pp.1252-1258
• /
• 2016

1,3-Propanediol (1,3-PD) is a valuable platform compound. Many studies have shown that the supplement of NADH plays a key role in the bioproduction of 1,3-PD from Klebsiella pneumoniae. In this study, the xylA and xylB genes from Escherichia coli were overexpressed individually or simultaneously in K. pneumoniae to improve the production of 1,3-PD by cofermentation of glycerol and xylose. Compared with the parent strain, the xylose consumption was significantly increased by the introduction of these two genes. The 1,3-PD titers were raised from 17.9 g/l to 23.5, 23.9, and 24.4 g/l, respectively, by the overexpression of xylA and xylB as well as their coexpression. The glycerol conversion rate (mol/mol) was enhanced from 54.1% to 73.8%. The concentration of 2,3-butanediol was increased by 50% at the middle stage but drastically decreased after that. The NADH and NADH/NAD⁺ ratio were improved. This report suggests that overexpression of xylA or xylB is an effective strategy to improve the xylose assimilation rate to provide abundant reducing power for the biosynthesis of 1,3-PD in K. pneumoniae.

• Annals of Hepato-Biliary-Pancreatic Surgery
• /
• v.27 no.2
• /
• pp.211-216
• /
• 2023

It has been shown that external pancreatic ductal stenting (EPDS) can reduce the incidence of clinically relevant postoperative pancreatic fistula. Although studies have described EPDS in open pancreaticoduodenectomy (PD), EPDS in minimally invasive PD has not been reported yet. Thus, the objective of this study was to describe the technique of EPDS in minimally invasive PD. The procedure was performed either laparoscopically or using a robot. Once PD was completed, key steps included triple enterotomy, threading of silk-suture through all enterotomies and exteriorization, completing posterior layer of pancreaticojejunostomy (PJ), railroading stent through preplaced silk-suture, intubation of stent into the pancreatic duct, completion of PJ, followed by hepaticojejunostomy and parietalization of jejunum at the stent exit site. EPDS in PD through a minimally invasive approach can be performed safely in selected cases with either a small-sized pancreatic duct or a soft pancreas.

• Childhood Kidney Diseases
• /
• v.13 no.2
• /
• pp.197-206
• /
• 2009

Purpose : Limited information is available on experiences of intravenous iron treatment in children. In this study, iron sucrose was administered intravenously to determine its effect, the factors predicting outcome, and safety in children on chronic dialysis. Methods : Twenty-one children whose serum ferritin levels were less than 100 ng/mL or transferrin saturations (TSAT) were less than 20% were enrolled. In 12 children on peritoneal dialysis (PD), the drug was infused intravenously as 200 mg/$m^2$ ($\leq$200 mg) at week 0, 2, 4, and 6. In 9 children on hemodialysis (HD), it was given intravenously as 8 weekly doses of 3 mg/kg ($\leq$100 mg) through week 0-7. Results : After treatment, serum ferritin levels increased significantly in both groups, and TSAT rose significantly in PD group. However, hemoglobin level did not rise significantly in both groups. Children with baseline hemoglobin less than 10 g/dL or baseline TSAT less than 20% showed significantly higher rise of hemoglobin after intravenous iron treatment. To the contrary, those with higher baseline hemoglobin and TSAT levels displayed higher rise in serum ferritin after the treatment. Although no serious adverse event occurred, TSAT levels exceeding 50% were noted in 6 patients in PD group. Conclusion : This suggests that 3 mg/kg/week of intravenous iron sucrose can be used safely in children on chronic HD, but 200 mg/$m^2$ every other week may incur excessive TSAT level in some patients on chronic PD.

• Polymer(Korea)
• /
• v.34 no.1
• /
• pp.25-31
• /
• 2010

Polymer core and metal shell composite particles have been prepared by the electroless nickel plating on the surface of monodisperse polystyrene microspheres. Various sizes of polystyrene particles with highly monodisperse state could be synthesized by controlling the dispersion medium in dispersion polymerization. Electroless nickel plating was performed on the polystyrene particle with diameter of $3.4\;{\mu}m$. The morphology of polystyrene/nickel composite particles was investigated to see the effect of the plating conditions, such as the $PdCl_2$ and glycine concentrations and the dropping rate of nickel plating solution, on nickel deposition. With $PdCl_2$ and glycine concentrations at more than 0.4 g/L and 1 M, respectively, more uniform nickel layer and less precipitated nickel aggregates were formed. At the given plating time of 2 h, the same amount of plating solution was introduced by varying the dropping rate. Though the effect of dropping rate on particle morphology was not noticeable, the dropping rate of 0.15 mL/min for 60 min showed rather uniform plating.