Publications by authors named "Kwangseok Ahn"

Cancer represents the second most deadly disease and one of the most important public health concerns worldwide. Surgery, chemotherapy, radiation therapy, and immune therapy are the major types of treatment strategies that have been implemented in cancer treatment. Unfortunately, these treatment options suffer from major limitations, such as drug-resistance and adverse effects, which may eventually result in disease recurrence.

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The failure of chemotherapy is a major challenge nowadays, and in order to ensure effective treatment of cancer patients, it is of great importance to reveal the molecular pathways and mechanisms involved in chemoresistance. Cisplatin (CP) is a platinum-containing drug with anti-tumor activity against different cancers in both pre-clinical and clinical studies. However, drug resistance has restricted its potential in the treatment of cancer patients.

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TENT4 enzymes generate 'mixed tails' of diverse nucleotides at 3' ends of RNAs via nontemplated nucleotide addition to protect messenger RNAs from deadenylation. Here we discover extensive mixed tailing in transcripts of hepatitis B virus (HBV) and human cytomegalovirus (HCMV), generated via a similar mechanism exploiting the TENT4-ZCCHC14 complex. TAIL-seq on HBV and HCMV RNAs revealed that TENT4A and TENT4B are responsible for mixed tailing and protection of viral poly(A) tails.

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For kesterite copper zinc tin sulfide/selenide (CZTSSe) solar cells to enter the market, in addition to efficiency improvements, the technological capability to produce flexible and large-area modules with homogeneous properties is necessary. Here, we report a greater than 10% efficiency for a cell area of approximately 0.5 cm and a greater than 8% efficiency for a cell area larger than 2 cm of certified flexible CZTSSe solar cells.

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Recently, highly efficient CZTS solar cells using pure metal precursors have been reported, and our group created a cell with 12.6% efficiency, which is equivalent to the long-lasting world record of IBM. In this study, we report a new secondary phase formation mechanism in the back contact interface.

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Lonicera japonica Thunb. (LJT) and Rehmannia glutinosa Libosch. (RGL) have been used traditionally as a herbal medicine in Korean medicine.

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Unlabelled: The structure of P3HT in P3HT:PCBM films is examined on a poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (

Pedot: PSS) substrate subjected to cryo-cooling to low temperature (-143 °C) followed by gradual heating to 50 °C. The behavior of these systems is examined in the absence and presence of an Al electrode on top of the P3HT:PCBM film. At temperatures below -10 °C, only the type-I phase of P3HT is observed.

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We report on the nanostructures of organic small-molecule pentacene crystals that have been vapor-deposited onto the capillary wave surfaces of thin liquid films. The characteristic lateral length of the capillary wave surface or the capillary length can be controlled by changing the thickness of the liquid films and, thus, the van der Waals interaction with the substrate. We find that the morphology of the organic crystals gradually varies from fractals to compact islands as the liquid film thickness increases.

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Farnesiferol C (FC) is one of the major compounds isolated from Ferula assafoetida, an Asian herbal spice used for cancer treatment as a folk remedy. Here, we examined the hypothesis that novel antiangiogenic activities of FC contribute to anticancer efficacy. In human umbilical vein endothelial cells (HUVEC), exposure to the 10 to 40 mumol/L concentration range of FC inhibited vascular endothelial growth factor (VEGF)-induced cell proliferation, migration, invasion, tube formation, and the expression of matrix metalloproteinase-2.

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