Real-time monitoring of toxic components from fine dust air pollutant samples by utilizing spark-induced plasma spectroscopy.

A growing modern-day concern is fine dust air pollution that contains heavy metals and ammonium ions (NH) from industrial and agricultural waste sources, respectively. In the current study, the development of an innovative and effective technique for real-time, quantitative monitoring of toxic fine dust components using plasma emission spectroscopy is presented as a complement to emergency preparedness plans aimed at reducing dust pollution. A novel spark-induced plasma spectroscopic (SIPS) device that can control the frequency and magnitude of plasma was developed for the toxic pollutants in this work.

A non-calorimetric approach for investigating the moisture-induced ageing of a pyrotechnic delay material using spectroscopies.

The degradation of thermal properties due to ageing such as burning rate and exothermic heat release are unsolved issues faced during a long-term storage of the pyrotechnic substances. Accordingly, we employed various non-calorimetric methods to investigate the thermal performance of pyrotechnic delay, which is exposed to various moisture-rich conditions at extended durations. The chemical and physical changes in the compositions of a pyrotechnic delay comprised of metal fuel (Zr-Ni alloy) and oxidants (KClO, BaCrO) are analysed for four different relative humidity levels using X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscope and laser-induced breakdown spectroscopy.

Porcine epidemic diarrhea vaccine evaluation using a newly isolated strain from Korea.

Porcine epidemic diarrhea virus (PEDV) infects pigs and causes an enteric disease that is characterized by vomiting and watery diarrhea. PEDV outbreaks have a tremendous financial impact on the worldwide pork industry. In South Korea, the incidence of PEDV has continued despite nationwide use of attenuated and inactivated vaccines, raising questions regarding the current vaccines' efficacy and the need for new vaccine development.

Pectinase-treated protects against chronic intermittent heat stress-induced testicular damage by modulating hormonal and spermatogenesis-related molecular expression in rats.

Background: Elevated testicular temperature disrupts spermatogenesis and causes infertility. In the present study, the protective effect of enzymatically biotransformed Meyer by pectinase (GINST) against chronic intermittent heat stress-induced testicular damage in rats was investigated.

Methods: Male Sprague-Dawley rats (4 wk old, 60-70 g) were divided into four groups: normal control (NC), heat-stress control (HC), heat-stress plus GINST-100 mg/kg (HG100), and heat-stress plus GINST-200 mg/kg (HG200) treatment groups.

Korean red ginseng improves testicular ineffectiveness in aging rats by modulating spermatogenesis-related molecules.

Korean red ginseng (Panax ginseng Meyer) is known to rejuvenate testicular effectiveness and the sperm maturation process by regulating redox proteins in aged rats. This study was performed to investigate the effect of Korean red ginseng water extract (KRG-WE) on the expression level of spermatogenesis-related key biomolecules and sex hormone receptors as well as enzymes regulating oxidation, histone deacetylation, and growth-related activities in aged rat testis. KRG-WE (200mg/kg) mixed with a regular pellet diet was administered to 12-month-old rats for 6months (KRG-AC), whereas the young (YC, 2months) and aged (AC, 12months) controls received the vehicle only.

Canola oil is an excellent vehicle for eliminating pesticide residues in aqueous ginseng extract.

Background: We previously reported that two-phase partition chromatography between ginseng water extract and soybean oil efficiently eliminated pesticide residues. However, an undesirable odor and an unpalatable taste unique to soybean oil were two major disadvantages of the method. This study was carried out to find an alternative vegetable oil that is cost effective, labor effective, and efficient without leaving an undesirable taste and smell.

Feasibility of FRAX for Prediction of Osteoporotic Vertebral Fractures in Korea.

Study Design: Retrospective study.

Purpose: To assess the feasibility and limitations of fracture risk assessment tool (FRAX) for osteoporotic vertebral fractures in the Korean population.

Overview Of Literature: The FRAX algorithm is country specific and uses clinical risk factor data to calculate an individual patient's 10-year probability of hip fracture and 10-year probability of major osteoporotic fracture.

Total hip arthroplasty using two-incision technique.

Background: To evaluate the effectiveness of minimally invasive surgery total hip arthroplasty (THA) using the two-incision technique as described by Mears.

Methods: From January 2003 to December 2006, sixty-four patients underwent total hip arthroplasty using the one-incision (group I) and two-incision (group II) technique by one surgeon. There were 34 hips in group I and 30 hips in group II.

Ligand-induced structural evolution of Pt55 nanoparticles: amine versus thiol.

We report the geometric and electronic effects of amine (with one lone pair electron) and thiol (with two lone pair electrons) ligands on the structural transformation of Pt(55) nanoparticles (NPs) by first-principles calculation. Although a cuboctahedral (COh) structure is less stable than an icosahedral (Ih) structure by 1.36 eV for a bare Pt(55) NP, the activation barrier from the COh to the Ih structure is very high, by 1.

Graphene veils and sandwiches.

We report a new and highly versatile approach to artificial layered materials synthesis which borrows concepts of molecular beam epitaxy, self-assembly, and graphite intercalation compounds. It readily yields stacks of graphene (or other two-dimensional sheets) separated by virtually any kind of "guest" species. The new material can be "sandwich like", for which the guest species are relatively closely spaced and form a near-continuous inner layer of the sandwich, or "veil like", where the guest species are widely separated, with each guest individually draped within a close-fitting, protective yet atomically thin graphene net or veil.

Squeaking sound in total hip arthroplasty using ceramic-on-ceramic bearing surfaces.

Purpose: To evaluate the causes and frequency of the squeaking sound in ceramic-on-ceramic THA.

Materials And Methods: This study included 61 hips of 50 patients who underwent ceramic-on-ceramic THA in our hospital from March 1999 to April 2005. The average age at the time of operation was 57.

Steering epitaxial alignment of Au, Pd, and AuPd nanowire arrays by atom flux change.

We have synthesized epitaxial Au, Pd, and AuPd nanowire arrays in vertical or horizontal alignment on a c-cut sapphire substrate. We show that the vertical and horizontal nanowire arrays grow from half-octahedral seeds by the correlations of the geometry and orientation of seed crystals with those of as-grown nanowires. The alignment of nanowires can be steered by changing the atom flux.

Phase diagram of Ag-Pd bimetallic nanoclusters by molecular dynamics simulations: solid-to-liquid transition and size-dependent behavior.

This report on the solid-to-liquid transition region of an Ag-Pd bimetallic nanocluster is based on a constant energy microcanonical ensemble molecular dynamics simulation combined with a collision method. By varying the size and composition of an Ag-Pd bimetallic cluster, we obtained a complete solid-solution type of binary phase diagram of the Ag-Pd system. Irrespective of the size and composition of the cluster, the melting temperature of Ag-Pd bimetallic clusters is lower than that of the bulk state and rises as the cluster size and the Pd composition increase.

Segregation and internal structures in the bimetallic clusters: density functional theory and molecular dynamics simulation.

We study the coalescence between two nanoclusters composed of different transition metals. Using a molecular dynamics simulation at 500 K, we reveal the segregation along with the evolution of the number of atomic bonds. The density functional theory calculation is also used to investigate the distribution tendency of the solute atoms inside the host cluster in segregated systems.

Molecular dynamics simulations of the diffusion and rotation of Pt nanoclusters supported on graphite.

We study the diffusion and rotation of Pt nanoclusters supported on graphite. Using molecular dynamics simulation, we reveal that the supported Pt clusters have two types of bottom layers: a hexagonal lattice and a rectangular lattice. The diffusion rate of the Pt clusters mainly depends on the types of bottom layers.