This study investigates high-frequency magnetic, dielectric, and microwave absorbing properties of iron particles dispersed in rubber matrix for the aim of thin microwave absorbers in gigahertz frequencies. High value of magnetic permeability and dielectric constant can be obtained in the composites containing thin flake iron particles which were prepared by mechanical forging of spherical iron powders using an attrition mill. The results are attributed to the reduction of eddy current loss (increase of permeability) and enhancement of space-charge polarization (increase of permittivity). However, if the initial particle size is too small (approaching to skin depth), milling effect for the increase of permeability is not observed and a low dielectric constant is predicted. If the particle size is too large, the permeability value is too small due to strong eddy current loss. With the iron particles controlled in size and shape (flakes) as the absorbent fillers, the thickness can be reduced as low as 1mm with respect to −5dB reflection loss in 1–2GHz.

Cyperi rhizoma, the rhizome of Cyperus rotundus L. (Family Cyperaceae), is a well-known functional food and traditional herbal medicine in Korea. It has been reported that Cyperi rhizoma has antioxidant and free radical scavenging activities that play a major role in protection of neurodegenerative disorders, such as Parkinson's disease (PD). In the present study, the neuroprotective effects of a water extract of Cyperi rhizoma (CRE) against 6-hydroxydopamine (6-OHDA)-induced neuronal damage were evaluated in an experimental model of PD. In PC12 cells, CRE showed a significant protective effect on cell viability at 50 and 100 microg/mL. CRE inhibited generation of reactive oxygen species and nitric oxide, reduction of mitochondrial membrane potential, and caspase-3 activity, which were induced by 6-OHDA. CRE also showed a significant protective effect against damage to dopaminergic neurons in primary mesencephalic culture. These results suggest that CRE has neuroprotective effects against 6-OHDA-induced toxicity through antioxidant and anti-apoptotic activities in an in vitro PD model.

In this study, titanium metal acts as the titanium source to prepare oriented titanate nanotube thin film. The effects of preparation parameters, such as reaction temperature, duration and post-treatment conditions, on the film morphology and stability have been examined. A general formation mechanism for oriented titanate nanotube thin film is proposed on the basis of detailed observations of the products using two-dimensional surface SEM studies and TEM images. The overall formation of titanate nanotubes can be summarized as a sequence of four steps: (a) titanium dissolution and alkali titanate hydrogel formation; (b) alkali titanate hydrogel dissolution, increased TiO32−, TiO2(OH)22− or TinO2n+m2m− concentration and layered Na2Ti3O7 formation; (c) layered Na2Ti3O7 growth; (d) nanotube formation via Na2Ti3O7 splitting and the multilayer scrolling process. The Na2Ti3O7 lamellar structures split between the (010) planes into nanosheets.

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A traditional Korean herbal formula (KH), which is based on Taeumjowi-tang, is currently the most widely used herbal formula in Korea. In this study, KH was administered to obese children for 30 days, and was found to be clinically safe and effective. The subjects were children admitted to hospital to be treated for obesity with relative body weights (%RBW) of 20% or more. Originally, there were 31 subjects, but nine dropped out during the experiment. There were eight girls and 14 boys, whose average age was 11.00 +/- 2.62 years, average weight was 53.37 +/- 17.29 kg, and average period (30-day amount) of KH dosage was 51.18 +/- 22.58 days. The short-term effects of KH on obese children were the reduction of their BMI from 24.34 +/- 3.10 to 23.26 +/- 3.00 kg/m2, of %RBW from 34.41 +/- 10.90 to 25.94 +/- 11.18% (p < 0.01), of body fat mass from 17.99 +/- 5.37 to 16.50 +/- 4.82 kg, and of body fat from 34.16 +/- 3.75 to 32.08 +/- 3.15% (p < 0.01). Concerning anthropometrical measurements, abdominal skin-fold decreased from 26.16 +/- 9.08 to 22.90 +/- 8.35 mm, as did subscapular skin-fold from 20.86 +/- 5.20 to 18.46 +/- 5.31 mm (p < 0.01). In terms of serum lipid levels, which are indices of heart disease, their total cholesterol decreased from 195.38 +/- 31.39 to 183.25 +/- 33.27 mg/dl, the arteriosclerosis index from 4.100 +/- 0.81 to 3.84 +/- 0.64 mg/dl (p < 0.05), and serum leptin level from 14.91 +/- 6.59 to 12.24 +/- 4.98 ng/ml (p < 0.01). Concerning the safety of KH, there were no significant changes in the subjects' livers, hearts, or kidneys. Nor were there any short-term signs of clinically serious side effects or withdrawal symptoms observed. The short-term effects of KH on obese children are weight loss and a decrease in obesity.