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The thick films with nominal composition of Ba0.6Sr0.4TiO3+0.4 wt% Li2O were prepared through tape casting. The structure and nonlinear dielectric properties of the resulting thick films were investigated within the sintering temperature range of 1050-1100 °C. The thick film specimens sintered at the relatively low temperatures exihibited dense and no crack microstructure due to the addition of sintering aid Li2O and modified process technology. An obvious influence of sintering temperature on the microstructure and nonlinear dielectric properties was detected. The discrepancy in nonlinear dielectric properties among the specimens sintered at different temperatures was qualitatively interpreted in terms of interfacial charge accumulation and defect dipole reorientation. Sintering at 1080 °C was determined to be preferred for the specimens with regard to the nonlinear dielectric properties. At room temperature, the specimen attained a dielectric constant of 3050 and a relatively low dielectric loss tangent of 0.15% at 10 kHz together with a extremely large figure of merits (FOM) of 580 and a tunability of 88% at 10 kHz and 200 kV/cm. [ABSTRACT FROM AUTHOR]

In order to investigate the area distribution and host selection of Leptotrombidium scutellare in Yunnan Province, a field survey was carried out during 2001 to 2009, based on different geographic location, topography, climate and ecological characteristics. A total of 16 491 L. scutellare were captured from the body surface of 9 838 small mammal hosts of 7 families, 18 genera, and 30 species in 4 orders, accounted for 17.73% (16,491/92,990) of all chigger mites collected. L. scutellare distributed in 12 counties, more in the northwest and south of the Province. Although L. scutellare could parasitize on different small mammal species, most of them were on Eothenomys miletus and Apodemus chevrieri.

Eothenomys miletus were captured in 19 counties of Yunnan Province. The distribution of species-abundance and the species-plots relationship between E. miletus and chigger mites were analyzed by using ecological statistic method. There were totally 40,052 chigger mites collected from the body surface of 1741 E. miletus. 111 species of chigger mites were identified. The species-abundance distribution showed that with the increase of mite individuals, the number of chigger mite species gradually decreased. Most mite species were rare ones. Species-plot relation indicated that with the number of mouse plots (samples of E. miletus) increasing, the number of chigger mite species increased. E. miletus collected quantity up to date still could not reflect the exact species richness of chigger mite.

Objective: To investigate the distribution of Leptotrombidium deliense among different small mammal hosts in some areas of Yunnan province., Methods: A field survey was carried out in some counties of Yunnan province and the small mammal hosts were captured, using mouse cages and traps with baits. Chigger mites on the surface of two auricles were scraped off by a bistoury, and then preserved in 70% ethanol. Every specimen of the chigger mites on the slides was finally identified into species under a microscope. Some conventional statistical methods were adopted to calculate all the collected chigger mite species and the constituent ratios of Leptotrombidium deliense in different areas and on different hosts, together with its prevalence and mean abundance on different hosts., Results: A total of 10 222 small mammal hosts were captured from 19 counties and identified as 11 families, 34 genera and 62 species in 5 orders, and 92 990 individuals of chigger mites were collected from the body surface of these small mammal hosts. All the collected chigger mites were identified as 3 subfamilies, 22 genera, and 225 species. Meanwhile, Leptotrombidium deliensee only accounted for 1.659% of the total. The host specificity of Leptotrombidium deliense was very low and 1544 individuals of Leptotrombidium deliense collected from 8518 small mammal hosts belonged to 6 families, 13 genera and 19 species in 3 orders. Our results showed that Leptotrombidium delienses were mainly collected from Insectivora and Rodentia. Leptotrombidium deliense had long been considered as the dominant species of chigger mites and the main vector of tsutsugamushi disease in Yunnan province of China, but our results seemed not thoroughly supporting this point of view., Conclusion: Traditionally, Leptotrombidium deliense was the dominant species and the main vectors of scrub typhus in Yunnan province. However, based on our results, the above view might be true in some local places and the composition of chigger mites and the main vector of tsutsugamushi disease might be different in regions and habitats in Yunnan province.

With the application of PCR technique in the medical field, PCR and its related techniques have made progress on detecting Orientia tsutsugamushi, which have played an important role in the early diagnosis of tsutsugamushi This paper summarizes the application of PCR and related techniques in detecting disease and pathogen research. This paper summarizes the application of PCR and related techniques in detecting O. tsutsugamushi.

In the title compound, [Co(C(7)H(5)O(2))(2)(C(5)H(6)N(2))(2)], the Co(II) atom is hexa-coordinated by four O atoms from two benzoate anions, and two N atoms from two 2-amino-pyridine mol-ecules, resulting in a distorted octa-hedral geometry. Both benzoate anions act as bidentate ligands and both 2-amino-pyridine mol-ecules are coordinated to the metal through their pyridyl N atoms. The crystal packing is stabilized by inter-molecular N-H⋯O hydrogen bonds, C-H⋯π, and π-π stacking inter-actions involving benzoate anions and 2-amino-pyridine mol-ecules.