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This paper presents micro-Pirani vacuum gauges using low-resistivity monocrystal silicon for the heaters and the heat sinks. We designed a new Pirani gauge with an embedded Wheatstone bridge made by thick-silicon resistors that allows an improvement in resolution and sensitivity. With the optimized Wheatstone bridge structure, the temperature coefficient of the gauges pressure measure decreases from 2.5%/°C to 0.74%/°C, and the resolution was optimized from 0.071 to 0.008 Torr at 1 Torr. In addition, the gauges were packaged into non-hermetic cavities by wafer-level AlGe eutectic bonding to undergo the wafer-dicing process, with sensitivity improved from 1.65 to 17.1 V/Torr at 1 Torr.

The traditional method for reconstructing cityscape relies greatly on the subjective judgment of designers, which makes the cityscape simple and homogenized. This paper aims to propose a new integrated approach to protect and design cityscape based on virtual reality (VR) and eye tracking technology. Through the integration and quantification of the eye tracking data and the protocol analysis data in the VR environment, this research has revealed the mechanism of identifying the cityscape features, and discovered the differences in the perception of the cityscape features by different people, thus proposing the multi-cultural integrated strategy for protecting cityscape. This research is of great significance for building a human-oriented scientific planning and protection method and promoting the application of cutting-edge digital technology in the field of smart city governance.

This paper presents a wafer-level packaged MEMS (Micro-electromechanical Systems) Pirani gauge with surrounded heat sinks with improved characteristics during the low limit of the cavity vacuum. Different to the reported gauges in other papers, it has four heat sinks, and one of these is the cap of the wafer-level package. And it utilizes two heaters and two constant resistors to construct an Whetstone Bridge, two meander-shaped suspended silicon coils is set as the heaters and two isolated comb-shaped silicon structures as the dual-lateral heat sinks. In addition, the substrate and capped wafers are used as dual-vertical heat sinks. The gauge is finally realized with the volume 1.4mm×1.2mm×0.5mm using the CMOS (Complementary Metal Oxide Semiconductor)-MEMS compatible process. The gauge was measured twice before and after wafer-level packaging. It denotes that with the introduction of the capped heat sink, the device bears a better sensitivity compared to the intermediate device before packaging. With a hole on the edge of the device, the gauge could be widely and flexibly used for the characterization of vacuum packaged MEMS devices.

As the costs of packaging and testing account for a substantial portion of microelectromechanical system (MEMS) devices, an effective and convenient characterization method is urgent to be investigated to lower the cost. In this paper, an electrical test method was utilized, and the test key used for a four-probe current-voltage test was designed to monitor the quality of the AuSn eutectic bonding. The electrical test can directly detect whether or not voids existed in the bonding layer. The difference in alloy state, for example, the existence of the (Au, Ni) 3Sn2 phase confirmed by the scanning electron microscope and energy dispersive x-ray spectroscopy test, can also be reflected by resistivity variation. The electrical test can be implemented automatically and conveniently unlike other characterization methods. Therefore, it is suitable to be applied in quality inspection in industrial production.

Heat shock factor-DNA interaction is critical for understanding the regulatory mechanisms of stress-induced gene expression in eukaryotes. In this study, we analyzed the in vivo binding of yeast heat shock factor (HSF) to the promoters of target genes ScSSA1, ScSSA4, HSP30 and HSP104, using chromatin immunoprecipitation. Previous work suggested that yeast HSF is constitutively bound to DNA at all temperatures. Expression of HSF target genes is regulated at the post-transcriptional level. However, our results indicated that HSF does not bind to the promoters of ScSSA4 and HSP30 at normal temperature (23 degrees C). Binding to these promoters is rapidly induced by heat stress at 39 degrees C. HSF binds to ScSSA1 and HSP104 promoters under non-stress conditions, but at a low level. Heat stress rapidly leads to a notable increase in the binding of HSF to these two genes. The kinetics of the level of HSF-promoter binding correlate well with the expression of target genes, suggesting that the expression of HSF target genes is at least partially the result of HSF-promoter binding stability and subsequent transcription stimulation.

To study the molecular regulation of nectary development, we cloned NEC1, a gene predominantly expressed in the nectaries of Petunia hybrida, by using the differential display RT-PCR technique. The secondary structure of the putative NEC1 protein is reminiscent of a transmembrane protein, indicating that the protein is incorporated into the cell membrane or the cytoplast membrane. Immunolocalization revealed that NEC1 protein is present in the nectaries. Northern blot analyses showed that NEC1 is highly expressed in nectary tissue and weakly in the stamen. GUS expression driven by the NEC1 promoter revealed GUS activity in the outer nectary parenchyma cells, the upper part of the filament and the anther stomium. The same expression pattern was observed in Brassica napus. GUS expression was observed as blue spots on the surface of very young nectaries that do not secrete nectar and do accumulate starch. GUS expression was highest in open flowers in which active secretion of nectar and starch hydrolysis had taken place. Ectopic expression of NEC1 resulted in transgenic plants that displayed a phenotype with leaves having 3-4 times more phloem bundles in mid-veins than the wild-type Petunia. The possible role of NEC1 gene in sugar metabolism and nectar secretion is discussed.