Development of a magnetic hybrid filter to reduce PM10 in a subway platform

This study investigated the reduction of particulate matter (PM) in a subway platform using self-developed magnetic hybrid filters (magnet-magnet (MM) and magnet-cascade (MC) filter). The magnetic hybrid filter systems were installed and operated in Jegi-dong subway station (J station) platform. The removal efficiency of PM₁₀ (particular matter with aerodynamic diameter less than 10 μm) was evaluated according to various influencing factors such as the combination of filters, linear velocity, and operating conditions of trains. As a result, the average removal efficiency of the MC filter (40.5%) was higher than that of the MM one (27.0%). The maximum PM₁₀ removal efficiencies by MM (34.1%) and MC (47.2%) filters were observed at 20 (linear velocity: 2.41 m/s) and 30 jog (8 m/s) dials, respectively. We additionally found that the removal efficiency of PM₁₀ using MM and MC filters suddenly decreased when the concentration of background PM₁₀ in the platform increased. Based on the results of this study, hybrid technology using two or more capture principles can remove PM more efficiently than technology using a single such principle.

Removal of particulate matter emitted from a subway tunnel using magnetic filters

We removed particulate matter (PM) emitted from a subway tunnel using magnetic filters. A magnetic filter system was installed on the top of a ventilation opening. Magnetic field density was increased by increasing the number of permanent magnet layers to determine PM removal characteristics. Moreover, the fan's frequency was adjusted from 30 to 60 Hz to investigate the effect of wind velocity on PM removal efficiency. As a result, PM removal efficiency increased as the number of magnetic filters or fan frequency increased. We obtained maximum removal efficiency of PM10 (52%), PM2.5 (46%), and PM1 (38%) at a 60 Hz fan frequency using double magnetic filters. We also found that the stability of the PM removal efficiency by the double filter (RSD, 3.2-5.8%) was higher than that by a single filter (10.9-24.5%) at all fan operating conditions.

Measurement of lymphedema using ultrasonography with the compression method

Lymphedema is swelling of soft tissues by accumulation of lymphatic fluid due to failure of the lymphatic drainage system. Although most measures for lymphedema focus on change of volume or size of the extremity, the physical properties of the tissue such as resistance to compression are also of clinical importance because they affect the quality of life of lymphedema patients. In this study, we aimed to compare the thickness and resistance to compression of the skin and subcutis between the affected and unaffected arms of patients with lymphedema by using ultrasonography together with the compression technique, and we also investigated the factors that have an influence on the results. Thirty-nine patients with post-mastectomy lymphedema participated in this study. All ultrasonographically-assessed thicknesses of skin and subcutaneous tissue in affected upper arms and forearms were significantly larger than the contralateral (p < 0.05) while all resistances to compression values were significantly lower (p < 0.05). These results suggest that measuring the resistance to compression and thickness using the compression method with ultrasonography may be a valuable tool for evaluating lymphedema after breast cancer surgery.

Development of adsorbent for the simultaneous removal of organic and inorganic contaminants from aqueous solution

In this study, a modified adsorbent, alginate complex beads, was prepared and applied to the removal of mixed contaminants from wastewater. The alginate complex beads were generated by the immobilization of powdered activated carbon and synthetic zeolites onto alginate gel beads, which were then dried at 110 °C for 20 h until the diameter had been reduced to 1 mm. This dry technique increased the hardness of the adsorbent to assure its durability and application. The adsorption onto the alginate complex beads of organic and inorganic compounds, as target contaminants, was investigated by performing both equilibrium and kinetic batch experiments. From the adsorption isotherms, according to the Langmuir equation, the alginate complex bead was capable of effectively removing benzene, toluene, zinc and cadmium. From kinetic batch experiments, the removal efficiencies of benzene, toluene, zinc and cadmium were found to be 66.5, 92.4, 74.1 and 76.7%, respectively, for initial solution concentrations of 100 mg L(-1). The results indicated that the adsorbent developed in this study has the potential to be a promising material for the removal of mixed pollutants from industrial wastewater or contaminated groundwater.

Measurement of soft tissue compliance with pressure using ultrasonography

Lymphedema is swelling, particularly in the subcutaneous tissues, due to accumulation of lymph. Previous imaging techniques have demonstrated associated structural changes and have been used for evaluating the status of soft tissues. However, the reliability of measurements using ultrasonography has not been evaluated and the ultrasonographic method has been unable to show changes in tissue softness. There is a need to determine if ultrasonography is a reliable technique to assess skin and subcutaneous thickness in the upper extremities with or without pressure and if the measure of compliance in soft tissue thickness is also reliable. Two examiners measured tissue thicknesses using ultrasonography and calculated the compliance with and without pressure on the forearm and upper arm, independently. The intra- and inter-rater cross-correlation coefficients of measuring soft tissue thickness were excellent (> 0.75) in the forearm (p < 0.05). In the upper arm, the reliabilities were fair-to-good. The intraclass correlation coefficients of pressure compliance in the forearm and upper arm were excellent and fair-to-good, respectively (p < 0.05). This study suggests that measurement of thickness of soft tissues using ultrasonography may be reliable and pressure compliance may reflect tissue softness in the upper extremity.

SJ-3366, a unique and highly potent nonnucleoside reverse transcriptase inhibitor of human immunodeficiency virus type 1 (HIV-1) that also inhibits HIV-2

We have identified and characterized a potent new nonnucleoside reverse transcriptase (RT) inhibitor (NNRTI) of human immunodeficiency virus type 1 (HIV-1) that also is active against HIV-2 and which interferes with virus replication by two distinct mechanisms. 1-(3-Cyclopenten-1-yl)methyl-6-(3,5-dimethylbenzoyl)-5-ethyl-2,4-pyrimidinedione (SJ-3366) inhibits HIV-1 replication at concentrations of approximately 1 nM, with a therapeutic index of greater than 4 x 10(6). The efficacy and toxicity of SJ-3366 are consistent when evaluated with established or fresh human cells, and the compound is equipotent against all strains of HIV-1 evaluated, including syncytium-inducing, non-syncytium-inducing, monocyte/macrophage-tropic, and subtype virus strains. Distinct from other members of the pharmacologic class of NNRTIs, SJ-3366 inhibited laboratory and clinical strains of HIV-2 at a concentration of approximately 150 nM, yielding a therapeutic index of approximately 20,000. Like most NNRTIs, the compound was less active when challenged with HIV-1 strains possessing the Y181C, K103N, and Y188C amino acid changes in the RT and selected for a virus with a Y181C amino acid change in the RT after five tissue culture passages in the presence of the compound. In combination anti-HIV assays with nucleoside and nonnucleoside RT and protease inhibitors, additive interactions occurred with all compounds tested with the exception of dideoxyinosine, with which a synergistic interaction was found. Biochemically, SJ-3366 exhibited a K(i) value of 3.2 nM, with a mixed mechanism of inhibition against HIV-1 RT, but it did not inhibit HIV-2 RT. SJ-3366 also inhibited the entry of both HIV-1 and HIV-2 into target cells. On the basis of its therapeutic index and multiple mechanisms of anti-HIV action, SJ-3366 represents an exciting new compound for use in HIV-infected individuals.

Cytotoxic cembrenolides and steroids from the formosan soft coral Sarcophyton crassocaule

Three new cytotoxic cembrenolide diterpenes, sarcocrassolide (1), crassolide (2), and 13-acetoxysarcocrassolide (3); a known cytotoxic cembrenolide, denticulatolide (4); and two cytotoxic steroids, (24S)-24-methylcholestane-3beta,5alpha,6beta-triol (5) and 24zeta-methylcholestane-3beta,5alpha,6beta,25-te traol-25-monoacetate (6), have been isolated from the Formosan soft coral Sarcophyton crassocaule. The structures of compounds 1-6 were determined by 1D and 2D spectral analysis.

Spontaneous symmetry breaking in the finite lattice quantum sine-gordon model

The spontaneous breaking of a global discrete translational symmetry in the finite lattice quantum sine-Gordon model is demonstrated by a density matrix renormalization group. A phase diagram in the coupling constant-inverse system size plane is obtained. Comparison of the phase diagram with a Woomany-Wyld finite-size scaling leads to an identification of the Berezinskii-Kosterlitz-Thouless transition in the quantum sine-Gordon model as the spontaneous symmetry breaking.

Deletion of SMN and NAIP genes in Korean patients with spinal muscular atrophy

Childhood-onset proximal spinal muscular atrophies (SMAs) are an autosomal recessive, clinically heterogeneous group of neuronopathies characterized by selective degeneration of anterior horn cells. The causative genes to be reported are survival motor neuron (SMN) and neuronal apoptosis inhibitory protein (NAIP) genes. The deletion of telomeric copy of SMN (SMN(T)) gene was observed in over 95% of SMAs. The deletion rate of NAIP gene is 20-50% according to disease severity. The objective of this article is to genetically characterize the childhood-onset spinal muscular atrophy in Koreans. Five Korean families (14 constituents containing 5 probands) with SMA were included in this study. Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) were used for the deletion analysis of SMN(T). Multiplex PCR method was used for NAIP analysis. Four probands showed deletion of SMNT gene. Deletion of SMN(C) (centromeric SMN) gene was found in one proband who did not show the deletion of SMN(T) gene and in the father of one proband who showed the deletion of SMN(T) gene. The deletion of NAIP gene was not found among all the studied individuals. The extent of deletion in Koreans was smaller than that in other studied population. PCR-RFLP deletion analysis can be applied to diagnose SMA and make a prenatal diagnosis.

Optimal electrode placement in facial nerve conduction study

This study was designed to determine the optimal sites for the active electrode in a nerve conduction study of each branch of the facial nerve. Twenty healthy male and female volunteers between 20 and 40 years old were investigated. Our criteria for the optimal site of the active electrode were initial negative deflection and maximal amplitude of the response and the most synchronized response. Optimal sites were found to be as follows: 1. Frontalis (temporal branch): a point midway between the hairline and the eyebrow along a line passing vertically through the pupil. 2. Orbicularis oculi (zygomatic branch): the medial quarter between the medial and lateral canthus. 3. Nasalis (buccal branch): muscle belly. 4. Triangularis (mandibular branch): 15 mm lateral and 25 mm below the corner of the mouth. 5. Orbicularis oris (zygomatic, mandibular and buccal branches): 2 mm below the lower lip midway between the midline and the corner of the mouth.