Observation of Highly Anisotropic Thermal Expansion of Polymer Films.

While dimensional change under thermal loading dictates various device failure mechanisms in soft materials, the interplay between microstructures and thermal expansion remains underexplored. Here, we develop a novel method to directly probe the thermal expansion for nanoscale polymer films using an atomic force microscope as well as confining active thermal volume. In a model system, spin-coated poly(methyl methacrylate), we find that the in-plane thermal expansion is enhanced by 20-fold compared to that along the out-of-plane directions in confined dimensions.

MALDI-MS analysis of disaccharide isomers using graphene oxide as MALDI matrix.

Disaccharides are sugars composed of two monosaccharides joined by a glycosidic linkage. The specific properties of a disaccharide depend on the type of the glycosidic linkage and the identity of the two component monosaccharides. In this work, seven disaccharide isomers (gentiobiose, isomaltose, melibiose, lactose, maltose, cellobiose, and sucrose) were analyzed by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) using a graphene oxide matrix.

Compartmentalized Arrays of Matrix Droplets for Quantitative Mass Spectrometry Imaging of Adsorbed Peptides.

Mass spectrometry imaging (MSI) based on matrix-assisted laser desorption/ionization (MALDI) provides information on the identification and spatial distribution of biomolecules. Quantitative analysis, however, has been challenging largely due to heterogeneity in both the size of the matrix crystals and the extraction area. In this work, we present a compartmentalized elastomeric stamp for quantitative MALDI-MSI of adsorbed peptides.

In-depth compositional analysis of water-soluble and -insoluble organic substances in fine (PM) airborne particles using ultra-high-resolution 15T FT-ICR MS and GC×GC-TOFMS.

Airborne particulate matter consisting of ionic species, salts, heavy metals and carbonaceous material is one of the most serious environmental pollutants owing to its impacts on the environment and human health. Although elemental and organic carbon compounds are known to be major components of aerosols, information on the elemental composition of particulate matter remains limited because of the broad range of compounds involved and the limits of analytical instruments. In this study, we investigated water-soluble and -insoluble organic compounds in fine (PM) airborne particles collected during winter in Korea to better understand the elemental compositions and distributions of these compounds.

Metabolite profiling study on the toxicological effects of polybrominated diphenyl ether in a rat model.

Polybrominated diphenyl ethers (PBDEs) are commonly used to retard the combustion of materials such as foam padding, textiles, or plastics, and numerous studies have confirmed the accumulation thereof in the environment and in fish, mammals, and humans. In this study, we used metabolomics to conduct an environmental risk assessment of the PBDE-209. We profiled the urinary metabolites of control and PBDE-treated rats (exposed to PBDE-209) using nuclear magnetic resonance (NMR) and mass spectrometry (MS).

Evaluation of the accuracy of dose delivery for IMRT based on transit dosimetry.

The authors have developed and evaluated a new method that uses transit dose in the treatment room in verification of dose delivery to patients. Five intensity modulated radiotherapy (IMRT) plans were selected from actual cancer patients, and transit dose was measured using MapCHECK 2 and an anthropomorphic phantom. The criteria used as a verification tool for the dose delivery to the patient were gamma-index-based dose comparison between the computed dose and measured dose.

1H-NMR-based profiling of organic components in leachate from animal carcasses disposal site with time.

Leachate, generated by the decomposition of animal carcasses, presents many environmental, sanitary, and food safety hazards. However, research on the characteristics of leachate is lacking. In this study, we performed biochemical profiling of leachate from two animal species (pig and cattle) in two soil types (sandy loam and sandy soil) using (1)H-NMR-based profiling, followed by multivariate data analysis.

A simplified analysis of dimethylarsinic acid by wavelength dispersive X-ray fluorescence spectrometry combined with a strong cation exchange disk.

Dimethylarsinic acid (DMA(V)) was pre-concentrated from water samples using a strong cation exchange (SCX) disk functionalized with sulfonic groups, before being analyzed by wavelength dispersive X-ray fluorescence spectrometry (WDXRF). The adsorption of DMA(V) occurred preferentially on the surface of the SCX disk, regardless of pH levels, probably due to interactions with the sulfonic functional groups. However, no other arsenic species, such as arsenate (iAs(V)), arsenite (iAs(III)), and monomethylarsonic acid (MMA(V)), were retained.

Characterizing the effect of heavy metal contamination on marine mussels using metabolomics.

Marine mussels (Mytilus) are widely used as bioindicators to measure pollution in marine environments. In this study, (1)H NMR spectroscopy and multivariate statistical analyses were used to differentiate mussel groups from a heavy metal-polluted area (Onsan Bay) and a clean area (Dokdo area). Principal component analysis and orthogonal projection to latent structure-discriminant analysis revealed significant separation between extracts of mussels from Onsan Bay and from the Dokdo area.

Health-related quality of life with KDQOL-36 and its association with self-efficacy and treatment satisfaction in Korean dialysis patients.

Background And Objectives: This study was conducted to measure the level of health-related quality of life (HRQOL) and to reveal the association of self-efficacy and treatment satisfaction with it in Korean dialysis patients.

Design, Setting, Participants, And Measurements: The study subjects were 237 patients receiving either hemodialysis (HD) or peritoneal dialysis (PD) from two university hospitals, from February to June in 2010. We investigated HRQOL using the Korean version of Kidney Disease Quality of Life Short Form 36 (KDQOL-36), and self-efficacy and treatment satisfaction by self-administrative questionnaire and their dialysis-related variables by reviewing clinical records.

Lanostane triterpenes from the fruiting bodies of Ganoderma lucidum and their inhibitory effects on adipocyte differentiation in 3T3-L1 Cells.

Four new lanostane triterpenes, butyl ganoderate A (1), butyl ganoderate B (2), butyl lucidenate N (3), and butyl lucidenate A (4), were isolated from the fruiting bodies of Ganoderma lucidum together with 14 known compounds (5-18). The structures of the new triterpenes were established by extensive spectroscopic studies and chemical evidence. In addition, the inhibitory effect of isolated compounds on adipocyte differentiation in 3T3-L1 cells was examined.

Randomized trial to compare the dosage of darbepoetin alfa by administration route in haemodialysis patients.

Aim: The doses of darbepoetin alfa required to maintain target haemoglobin levels after s.c. or i.

Difficulty in improving malnutrition and low-grade inflammation in diabetic patients on peritoneal dialysis.

Continuous ambulatory peritoneal dialysis (CAPD) is commonly used for renal replacement therapy in diabetes mellitus (DM) patients. We investigated the changes of peritoneal transport characteristics, nutritional status, and adequacy and inflammation parameters in diabetic CAPD patients (N = 17) compared to non-diabetic patients (N = 23). Peritoneal equilibrium testing, nutritional, biochemical, and anthropometric parameters and adequacy were prospectively assessed at 1 (baseline), 6 and 12 months after initiating CAPD.

Determination of polychlorinated biphenyls in transformer oil using various adsorbents for solid phase extraction.

Various adsorbents for a solid phase extraction (SPE) method were used to study their ability to separate PCBs from transformer oil to rapidly determine their sub-ppm concentration in the transformer oil. Approximately 90% of the transformer oil could be removed from the PCBs by using a hydrophilic-lipophilic balanced copolymer (HLB) adsorbent, but the recovery of deca-chlorobiphenyl (deca-CB) used as a surrogate was only 24.5% due to lose during this cleanup process.

In vitro activity of kaempferol isolated from the Impatiens balsamina alone and in combination with erythromycin or clindamycin against Propionibacterium acnes.

The in vitro antibacterial activity against antibiotic-resistant Propionibacterium acnes of kaempferol isolated from the Impatiens balsamina alone and in combination with erythromycin or clindamycin antibiotics was investigated. The antibiotic combination effect against antibiotic-resistant P. acnes was studied by checkerboard test.

Development of new cleanup method of polychlorinated dibenzo-p-dioxins/dibenzofurans in fish by freezing-lipid filtration.

Freezing-lipid filtration as a new method has been developed for the rapid determination of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDDs/Fs) in biological samples. This method can effectively reduce the time of sample pretreatment, labor and amount of solvents compared with conventional methods. By freezing-lipid filtration procedure, about 90% of lipids in extract could be removed without any significant loss of PCDD/Fs.

Preparative isolation of four ginsenosides from Korean red ginseng (steam-treated Panax ginseng C. A. Meyer), by high-speed counter-current chromatography coupled with evaporative light scattering detection.

Ginseng (Panax ginseng C. A. Meyer) has been well known to have a variety of ginsenosides that show diverse biological activities.

Qualitative and quantitative determination of ten major saponins in Platycodi Radix by high performance liquid chromatography with evaporative light scattering detection and mass spectrometry.

Saponins in Platycodi Radix (platycosides) exhibit potent biological activities in mammalian systems, including several beneficial effects such as anti-inflammatory, immunomodulatory and anti-obesity activities. In this study, we developed a new HPLC separation coupled with evaporative light scattering detector (ELSD) for the simultaneous quantitative determination of ten major saponins in Platycodi Radix. Simultaneous separation of these saponins was achieved on a C18 analytical column.

Usefulness of the dialysis adequacy and transport test in peritoneal dialysis.

Instead of the peritoneal equilibration test (PET), the dialysis adequacy and transport test (DATT) is an easy and convenient method to classify peritoneal transport type. However, the peritoneal transport characteristics obtained from the DATT and the PET are not same in some cases. In the present study, we investigated the ability of the DATT to identify peritoneal transport characteristics in a clinical setting, and we analyzed the characteristics of patients with a discrepancy between the DATT and the PET.

Structural determination of cyclitol derivatives by fast-atom bombardment tandem mass spectrometry.

Three cyclitol derivatives were isolated from the marine sponge Sarcotragus sp. by reversed-phase high-performance liquid chromatography and analyzed by fast-atom bombardment mass spectrometry (FAB-MS). Their structural elucidation was carried out with FAB tandem mass spectrometry (FAB-MS/MS).

Simultaneous determination of anabolic steroids and synthetic hormones in meat by freezing-lipid filtration, solid-phase extraction and gas chromatography-mass spectrometry.

Estradiol, testosterone, progesterone, zeranol and diethylstilbestrol including estradiol metabolites were determined simultaneously in meat. Extraction of growth hormones was carried out by ultasonication using a methanol-water mixture. The growth hormones in the meat extract can be effectively separated from lipids by freezing-lipid filtration, followed by C8-solid phase extraction (SPE).