Gas sensors for oxides synthesis by hydrothermal and microwave hydrothermal methods

so far, gas sensors are playing an increasingly important role in environmental detection, agricultural production, medical treatment and other fields. Semiconductor oxide gas sensors are often used to detect toxic gases because of their low cost, simple manufacture, fast response, good selectivity and high sensitivity. There are many methods to prepare semiconductor oxides, such as hydrothermal synthesis, microwave hydrothermal synthesis and sol-gel synthesis. The advantages of hydrothermal synthesis and microwave hydrothermal synthesis are high economic efficiency and simple operation. The synthesized oxides have many different morphologies, such as zero dimensional, one-dimensional, two-dimensional, three-dimensional and so on. These diff erent morphologies are conducive to gas diff usion and enhance gas sensing performance. Especially the hierarchical structure can greatly improve the gas sensing performance due to its large specifi c surface area, large porosity and high carrier concentration. This paper describes the SMO gas sensor prepared by hydrothermal method and microwave hydrothermal method

A comparative study on the performance of three color schemes in landscape preference tests

The photo color is recognised as one of the most significant but not fully understood factors influencing the results of landscape preference research. In this context, this paper compares the performances of three photo color schemes (original, rendered and white-black color schemes) frequently used in landscape preference tests to figure out which is the more suitable alternative to an original color photo. Statistics analysis results demonstrated that: 1) In general, the photo color schemes particularly the white-black scheme will significantly affect the results of landscape preference test. Compared with white-black, color in any other forms can increase the degree of preference for a given landscape. 2) The photo color scheme plays a decisive role in respondent’s judgment on some landscape attributes. Original color, White-black color and Rendered color schemes are better suited in landscape preference tests that highlight the effect of color, characteristic and naturalness respectively. 3) When the Rendered color scheme is used as an alternative to the Original color scheme, it has a much better performance than the White-black Color Scheme and is therefore recommended as the prior alternative color scheme to the Original color scheme under most scenarios in landscape preference research. Based on these results, it is suggested that color should be more carefully treated according to its different performance in landscape cognition research

Analysis of four achaete-scute homologs in Bombyx mori reveals new viewpoints of the evolution and functions of this gene family

<p>Abstract</p> <p>Background</p> <p><it>achaete-scute </it>complexe (<it>AS-C</it>) has been widely studied at genetic, developmental and evolutional levels. Genes of this family encode proteins containing a highly conserved bHLH domain, which take part in the regulation of the development of central nervous system and peripheral nervous system. Many <it>AS-C </it>homologs have been isolated from various vertebrates and invertebrates. Also, <it>AS-C </it>genes are duplicated during the evolution of Diptera. Functions besides neural development controlling have also been found in <it>Drosophila AS-C </it>genes.</p> <p>Results</p> <p>We cloned four <it>achaete-scute </it>homologs (<it>ASH</it>) from the lepidopteran model organism <it>Bombyx mori</it>, including three proneural genes and one neural precursor gene. Proteins encoded by them contained the characteristic bHLH domain and the three proneural ones were also found to have the C-terminal conserved motif. These genes regulated promoter activity through the Class A E-boxes <it>in vitro</it>. Though both <it>Bm-ASH </it>and <it>Drosophila AS-C </it>have four members, they are not in one by one corresponding relationships. Results of RT-PCR and real-time PCR showed that <it>Bm-ASH </it>genes were expressed in different larval tissues, and had well-regulated expressional profiles during the development of embryo and wing/wing disc.</p> <p>Conclusion</p> <p>There are four <it>achaete-scute </it>homologs in <it>Bombyx mori</it>, the second insect having four <it>AS-C </it>genes so far, and these genes have multiple functions in silkworm life cycle. <it>AS-C </it>gene duplication in insects occurs after or parallel to, but not before the taxonomic order formation during evolution.</p