• IMMUNE NETWORK
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• v.16 no.2
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• pp.134-139
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• 2016

Programmed death-1 (PD-1) is a strong negative regulator of T lymphocytes in tumor-microenvironment. By engaging PD-1 ligand (PD-L1) on tumor cells, PD-1 on T cell surface inhibits anti-tumor reactivity of tumor-infiltrating T cells. Systemic blockade of PD-1 function using blocking antibodies has shown significant therapeutic efficacy in clinical trials. However, approximately 10 to 15% of treated patients exhibited serious autoimmune responses due to the activation of self-reactive lymphocytes. To achieve selective activation of tumor-specific T cells, we generated T cells expressing a dominant-negative deletion mutant of PD-1 (PD-1 decoy) via retroviral transduction. PD-1 decoy increased IFN-γ secretion of antigen-specific T cells in response to tumor cells expressing the cognate antigen. Adoptive transfer of PD-1 decoy-expressing T cells into tumor-bearing mice potentiated T cell-mediated tumor regression. Thus, T cell-specific blockade of PD-1 could be a useful strategy for enhancing both efficacy and safety of anti-tumor T cell therapy.

• IMMUNE NETWORK
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• v.20 no.1
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• pp.8.1-8.15
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• 2020

Immune checkpoint blockade targeting PD-1 and PD-L1 has resulted in unprecedented clinical benefit for cancer patients. Anti-PD-1/PD-L1 therapy has become the standard treatment for diverse cancer types as monotherapy or in combination with other anticancer therapies, and its indications are expanding. However, many patients do not benefit from anti-PD-1/PD-L1 therapy due to primary and/or acquired resistance, which is a major obstacle to broadening the clinical applicability of anti-PD-1/PD-L1 therapy. In addition, hyperprogressive disease, an acceleration of tumor growth following anti-PD-1/PD-L1 therapy, has been proposed as a new response pattern associated with deleterious prognosis. Anti-PD-1/PD-L1 therapy can also cause a unique pattern of adverse events termed immune-related adverse events, sometimes leading to treatment discontinuation and fatal outcomes. Investigations have been carried out to predict and monitor treatment outcomes using peripheral blood as an alternative to tissue biopsy. This review summarizes recent studies utilizing peripheral blood immune cells to predict various outcomes in cancer patients treated with anti-PD-1/PD-L1 therapy.

• Journal of the Korean Ceramic Society
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• v.41 no.8
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• pp.578-581
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• 2004

In this study, we proposed the novel method that can crystallize the amorphous silicon by adjacent Pd-MILC enhanced Ni-MILC. With this method, the MILC rate was about 15 ${\mu}$m/h at 550$^{\circ}C$ which is four times faster than conventional MILC rate. The crystallization rate increased rapidly with the spacing between Ni and Pd decreased. And it was independent on Ni and Pd layer thickness and amorphous silicon active width. However, when Pd was capped by a Ni layer, there's no enhancement on Ni-MILC. This phenomenon implies that the enhancement of Ni-MILC rate comes from not Pd material itself but Pd-MILC induced tensile stress. We can explain these phenomena with a novel MILC mechanism.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.10
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• pp.895-900
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• 2007

Partial discharge(PD) test can be performed either when the rotating machine is not operating(off-line) or during normal machine operation(on-line). This paper presents an on-line and off-line PD test on a large hydro-generator and induction motor using the same PD acquisition system(PDAS) and ceramic coupler(CC) sensor. PD signal characteristics of CC sensor proved similar with that of epoxy mica coupler(EMC) sensor as a results of PD test for simulated defect winding and frequency response test. A comparison of on-line and off-line PD test for PD characteristic parameters-phase resolved PD(PRPD), maximum PD value(Qmax) and PD occurrence energy(POE)-indicated that on-line PD test could reliably and effectively diagnose insulation conditions which were verified by off-line PD test.

• Journal of the Mineralogical Society of Korea
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• v.8 no.1
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• pp.13-22
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• 1995

Phase relations of the Pd-Sb system were investigated using the sealed-capsule technique; the quenched run products were studied by reflected light microscopy, X-ray diffraction, and electron microprobe analysis. Eight binary phases were confirmed to exist in the system: Pd20Sb7, Pd31Sb12, Pd8Sb3 (mertieite II), Pd5Sb2, Pd2Sb, Pd5Sb3, PdSb (sudburyite), and PdSb2, (unnamed PdSb2), The X-ray powder diffraction data of all the phases, except for Pd5Sb3, however, may be indexable on an orthorhombic cell, space group Cmc2, with a=3.362(1), b=17.484(7), c=6.934(2)$\AA$. Some physical properties as well as re-determined cell parameters are newly established. A revised phase relations of the Pd-Sb system are presented.

• Journal of the Korean Vacuum Society
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• v.18 no.4
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• pp.281-287
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• 2009

Pd was deposited on magnesium-oxide-covered magnesium ribon substrate by metal thermal evaporation method in high vacuum. The electronic and chemical properties of Pd samples with different coverages were studied using in-situ X-ray Photoelctron Spectroscopy (XPS) and Field Emission Scanning Electron Microscopy (SEM). For relatively lower amounts of Pd deposited(< 1nm), separate Pd particles could be observed, whereas at higher Pd coverages, Pd thin films caused by agglomeration of Pd nanoparticles was found. The metal support interaction with Pd-support was observed. The Pd atoms on the metal oxide/metal interface were partially negative charged by charge transfer.

• Journal of the Korean Chemical Society
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• v.50 no.5
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• pp.369-373
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• 2006

Arylation reactions of styrene catalyzed by Pd(CF3CO2)2-sulfides and Pd(CF3CO2)2-phosphines were investigated. The yield of trans-stilbene, the main product, increased as the basicity of the substituents on the aryl groups of the phosphines increased and the steric hindrance of the substituents decreased. The mechanism of the aryl migration of arylphosphines to styrene is proposed to involve the electrophilic attack of Pd to the phenyl group on the phosphines. The phosphine systems were found to be more effective than the sulfide ones.

• 한국전기화학회:학술대회논문집
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• 2002.07a
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• pp.211-218
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• 2002

In this study, Pt/Pd (1.1), PtPd (2:1) and PtPd (3:1) binary catalysts and Pt/Ru/Pd (5:4:1) ternary catalyst were designed. The catalysts were synthesized by impregnation method using $NaBH_4$ as a reducing agent. A good catalyst for methanol oxidation requires low on-set potential, stable durability and low activation energy. In order to investigate the catalytic activity for the methanol oxidation, electrochemical measurements such as cyclic voltammetry and chronoamperometry were peformed in sulfuric acid with/without methanol solution. In order to calculate the activation energy of the reaction, electrochemical measurements were also tested at different temperatures. For investigation of the structural analysis such as particle size and alloying, X-ray diffraction and transmission electron microscopy analysis were used. In order to identify the role of the Pd and to determine the composition of the surface of the Pt/Pd nanoparticles, X-ray photoelectron spectroscopy (XPS) analysis was investigated. The XPS spectra of Pd showed that Pd appears only as a metallic state in the binary catalysts. The chemical states of Pt in PtPd catalysts are both metallic and oxidative. Polarization curves and power density data were obtained by testing the DMFC unit cell performance of PtPd and PtRuPd catalysts. These data showed that Pt/Pd (2:1) and Pt/Ru/Pd (5:4:1) have better performance than Pt and Pt/Ru, respectively.

• Journal of Technologic Dentistry
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• v.30 no.2
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• pp.9-16
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• 2008

The surface microstructural changes, mechanical properties and corrosion resistance of Ti-Pd alloys for dental biomaterials have been investigated. Ti, Ti-Pd alloys were melted in arc furnace and the corrosion resistance of Ti-Pd alloys was evaluated by anodic polarization test. The surface microstructural changes and mechanical properties of Ti-Pd alloys were analysed by scanning electron microscope and Vickers micro-hardness tester. The vickers hardnees of pure Ti improved by addition of Pd but Ti-25Pd alloy showed decreasing compared with Ti-15Pd. And anodic polarization and potentiostatic test were conducted in 5% HCl to quantify the resistance to corrosion with the addition of Pd, There was no significant difference in corrosion resistance between pure Ti, Ti-5Pd and Ti-15Pd alloy. However, Ti-25Pd alloy showed decreasing compared with pure Ti in corrosion resistance. From these results, it was concluded that newly formulated Ti-15Pd experimental alloy have adequate hardness and high corrosion resistance, and this alloy is promising candidate for a successful dental casting alloy.

• Electrical & Electronic Materials
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• v.1 no.3
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• pp.251-260
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• 1988

n형 GaAs에 음성접촉을 형성함에 있어서 Au-Ge 공융합금을 용해시키는 alloying 보다는 sintering을 필요로 하는 Su-Pd-Ge계의 새로운 융성접촉을 도입하였다. Au-Pd-Ge계의 최적의 음성조건을 조사하기 위하여 Au/Pd/Ge, Au/Ge/Pd, Au/Pd/Ge/Pd 그리고 Au/Pd/Au/Ge 음성접촉을 제조하였다. 비접촉저항을 조사하는데 있어서 sintering 온도는 390-450.deg.C사이였고 시간은 30초에서 6분 사이였다. Au-Pd-Ge계의 비접촉저항은 alloying된 Au/Pd/Ge 접촉의 그것에 필적할 만큼 낮았으며 특히 Au/Ge/Pd 접촉은 430.deg.C, 3분의 sintering 조건에서 가장 낮은 1.2*$10^{-6}$.OMEGA..$cm^{2}$의 비접촉저항을 나타냈다. Au/Ge/Pd 접촉의 표면형상 및 접촉패턴 가장자리는 450.deg.C에서 2분 이상 sintering된 접촉을 제외하고는 sintering 후에 as-deposited 상태와 다를 바가 없었다. 430.deg.C, 3분 sintering에서 가장 낮은 비접촉저항을 나타낸 Au/Ge/Pd 접촉의 비접촉저항은 430.deg.C에서 Ge/Pd 두께 변화에 비교적 변화가 적었다.