Publications by authors named "Chul-sung Kim"

This research explores the alteration of metal-organic frameworks (MOFs) using a method called postsynthetic metal exchange. We focus on the shift from a Zn-based MOF containing a [ZnO(COO)] secondary building unit (SBU) of octahedral site symmetry (ANT-1(Zn)) to a Fe-based one with a [FeO(COO)] SBU of trigonal prismatic site symmetry (ANT-1(Fe)). The symmetry-mismatched SBU transformation cleverly maintains the MOF's overall structure by adjusting the conformation of the flexible 1,3,5-benzenetribenzoate linker to alleviate the framework strain.

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Among various iron carbide phases, χ-FeC, a highly active phase in Fischer-Tropsch synthesis, was directly synthesized using a wet-chemical route, which makes a pre-activation step unnecessary. In addition, χ-FeC nanoparticles were encapsulated with mesoporous silica for protection from deactivation. Further structural analysis showed that the protective silica shell had a partially ordered mesoporous structure with a short range.

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All quiet on the nitrogen front. The dissociation of stable diatomic nitrogen molecules (N) is one of the most challenging tasks in the scientific community and currently requires both high pressure and high temperature. Here, we demonstrate that N can be dissociated under mild conditions by cyclic strain engineering.

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Fe O H nanostructures were incorporated into commercially available and highly porous alumina using the temperature-regulated chemical vapor deposition method with ferrocene as an Fe precursor and subsequent annealing. All processes were conducted under ambient pressure conditions without using any high-vacuum equipment. The entire internal micro- and mesopores of the AlO substrate with a bead diameter of ∼2 mm were evenly decorated with Fe O H nanoparticles.

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Most interesting phenomena of condensed matter physics originate from interactions among different degrees of freedom, making it a very intriguing yet challenging question how certain ground states emerge from only a limited number of atoms in assembly. This is especially the case for strongly correlated electron systems with overwhelming complexity. The Verwey transition of FeO is a classic example of this category, of which the origin is still elusive 80 years after the first report.

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Background: The aim of this study was to investigate the prognostic value of preoperative systemic inflammation markers in upper tract urothelial carcinoma (UTUC).

Methods: A total of 1137 patients who underwent radical nephroureterectomy with bladder cuff excision at 9 institutions from 2004 to 2015, were retrospectively reviewed. The Glasgow Prognostic Score (GPS), modified GPS (mGPS), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) for each patient were calculated.

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Purpose: The aim of this study was to determine the effect of preoperative chronic kidney disease (CKD) on the prognosis of patients with upper urinary tract urothelial carcinoma (UTUC) who had undergone radical nephroureterectomy (RNU).

Results: The median follow-up period was 31.1 months (interquartile range: 16.

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We have demonstrated that the Verwey transition, which is highly sensitive to impurities, survives in anisotropic Gd-doped magnetite nanoparticles. Transmission electron microscopy analysis shows that the nanoparticles are uniformly distributed. X-ray photoelectron spectroscopy and EDS mapping analysis confirm Gd-doping on the nanoparticles.

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Purpose: Recently, several studies have shown that the De Ritis ratio (aspartate transaminase/alanine transaminase) can be a useful prognostic biomarker for certain types of malignant tumors. However, the prognostic value of the De Ritis ratio in patients with upper tract urothelial carcinoma remains largely unknown. The aim of the present study was to evaluate the prognostic significance of the De Ritis ratio in patients who had undergone radical nephroureterectomy (RNU) for upper urinary tract urothelial carcinoma.

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Iron-nitrogen on carbon (Fe-N/C) catalysts have emerged as promising nonprecious metal catalysts (NPMCs) for oxygen reduction reaction (ORR) in energy conversion and storage devices. It has been widely suggested that an active site structure for Fe-N/C catalysts contains Fe-N coordination. However, the preparation of high-performance Fe-N/C catalysts mostly involves a high-temperature pyrolysis step, which generates not only catalytically active Fe-N sites, but also less active large iron-based particles.

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Purpose: The purpose of this study is to evaluate the effect of diabetes mellitus (DM) and preoperative glycemic control on prognosis in Korean patients with upper tract urothelial carcinoma (UTUC) who underwent radical nephroureterectomy (RNU).

Materials And Methods: A total of 566 patients who underwent RNU at six institutions between 2004 and 2014 were reviewed retrospectively. Kaplan-Meier and Cox regression analyses were performed to assess the association between DM, preoperative glycemic control, and recurrence-free, cancer-specific, and overall survival.

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Purpose: We aimed to analyze the characteristics of urinary retention (UR) in female inpatients managed with medical treatments.

Materials And Methods: We retrospectively analyzed the medical records of female inpatients referred to the department of urology for UR at our institution from January 2009, to December 2014. UR was defined as a difficulty in self-voiding despite a sufficient urine volume or >300-mL postvoid residual.

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Using a simple thermal treatment under a CO flow, uniform micrometer-sized iron oxalate dihydrate cubes prepared by hydrothermal reaction were transformed into Fe5C2@C nanoparticles to form a mesoporous framework; the final structure was successfully applied to the high-temperature Fischer-Tropsch reaction and it showed high activity (CO conversion = 96%, FTY = 1.5 × 10(-4) molCO gFe(-1) s(-1)) and stability.

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Gross hematuria secondary to vesical varices is an unusual presentation. We report such a case recurrent gross hematuria in a male patient who had a history of bladder substitution with ileal segments that had been treated by balloon-occluded percutaneous transhepatic obliteration of vesical varices.

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Purpose: To identify the prostate cancer detection rate on the patients who had second prostate biopsy out of the patients who were reported negative in their first biopsy.

Materials And Methods: From July 2006 to February 2012, prostate biopsy was performed on 843 patients with over 4 ng/ml and on 618 biopsy negative patients PSA was performed from between 6 months and 9 months after biopsy. On 164 patients, second biopsy was performed, and 42 patients were selected.

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Extraosseous osteosarcoma originating from paratesticular soft tissue is an extremely rare type of malignant tumor. With the exception of the present study, only one other case of osteosarcoma originating from paratesticular soft tissue has previously been reported. A 52-year-old man presented with a painless scrotal swelling and palpable mass.

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New iron-based mixed-polyanion compounds Li(x)Na(4-x)Fe(3)(PO(4))(2)(P(2)O(7)) (x = 0-3) were synthesized, and their crystal structures were determined. The new compounds contained three-dimensional (3D)sodium/lithium paths supported by P(2)O(7) pillars in the crystal. First principles calculations identified the complex 3D paths with their activation barriers and revealed them as fast ionic conductors.

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Purpose: To report our initial clinical experience and perioperative outcomes of retroperitoneal laparoendoscopic single-site surgery (RLESS) for upper urinary tract surgery.

Materials And Methods: Between June 2009 and October 2010, we performed RLESS in 23 patients for various indications including radical nephrectomy (n=4), nephroureterectomy (n=2), simple nephrectomy (n=10), and renal cyst ablation (n=7). RLESS was performed with a homemade single-port device with a conventional rigid laparoscopic instrument and laparoscope.

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Based on the optical deflection method, the resonant characteristics of a microcantilever under various pressure have been observed at room temperature to understand the pressure-dependent dissipation effect. Especially, the quality factor of the cantilever has been measured for up to fourth harmonic mode of cantilever resonance as a function of pressure between 0.1 and 1000 Torr.

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Cubic-spinel MnFe2O4 magnetic nanoparticles (NPs) were prepared, with an average particle size of about 4 nm determined from a high-resolution transmission electron microscope. When the NPs were proton-irradiated, the lattice constants decreased with increasing proton irradiation. Before the proton irradiation, the NPs exhibited 36.

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Introduction: Urogenital TB (UGTB) is the second most common form of extrapulmonary TB (EPTB) in countries with severe epidemic situation and the third most common form in regions with low incidence of TB. Male genital TB (MGTB) seems to be a rare disease. Nevertheless, 77% of men who died from TB of all localizations had prostate TB that had mostly been overlooked during their life time.

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Purpose: Studies of genetic variation in the prostate-specific antigen (PSA) gene have improved the diagnostic accuracy of PSA for diagnosing prostate diseases in Caucasians. However, the reference ranges and pharmacokinetics of PSA differ significantly according to race. Therefore, we evaluated the association between genetic variations in the PSA promoter area and benign prostatic hyperplasia (BPH) phenotypes in Korean BPH patients.

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We report a simple and scalable method for the separation of semiconducting single-walled carbon nanotubes (SWNTs) from metallic SWNTs using magnetic nanoparticles (MNPs) functionalized with polycationic tri-aminated polysorbate 80 (TP80). MNPs-TP80 are selectively adsorbed on acid-treated semiconducting SWNTs, which makes the semiconducting SWNTs be highly concentrated to over 95% under a magnetic field. Almost all the field effect transistor network devices, which were fabricated using separated semiconducting SWNTs, exhibited a p-type semiconducting behavior with an on/off ratio of higher than 10(4).

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Sexually transmitted infections are diseases provoking a great social and economic burden as well as health-related problems, and with the aging of society and the extension of life expectancy sexually transmitted infections in the elderly have drawn more attention these days. For the management of sexually transmitted infections in this population, basic epidemiological data need to be established. In this study, 1,804 persons from the general population aged over 60 years visiting health examination centers were tested for syphilis, gonorrhea, and chlamydia, and interviewed about the patterns of sexual behavior of elderly people through questionnaires.

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The Korean Antimicrobial Resistance Monitoring System was established and the first nationwide surveillance of bacterial uropathogens was conducted during the period from January 2008 to June 2009. With the cooperation of 34 medical centers throughout South Korea, a total of 1994 strains belonging to clinically relevant bacterial uropathogens were collected from patients with community-acquired urinary tract infections (UTIs). To compare with past data, understand a trend of antimicrobial resistance, and ultimately determine new regimens for empirical treatment of uncomplicated cystitis, the antimicrobial susceptibilities against Escherichia coli in uncomplicated cystitis to commonly prescribed drugs were investigated.

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