Thioredoxin, a small, ubiquitous protein which participates in redox reactions through the reversible oxidation of its active center dithiol to a disulfide, is an essential protein in Bacillus subtilis. A variety of stresses, including heat or salt stress or ethanol treatment, strongly enhanced the synthesis of thioredoxin inB. subtilis. The stress induction of the monocistronictrxA gene encoding thioredoxin occurs at two promoters. The general stress sigma factor, ςB, was required for the initiation of transcription at the upstream site, SB, and the promoter preceding the downstream start site, SA, was presumably recognized by the vegetative sigma factor, ςA. In contrast to the heat-inducible, ςA-dependent promoters preceding the chaperone-encoding operons groESL anddnaK, no CIRCE (for controlling inverted repeat of chaperone expression) was present in the vicinity of the start site, SA. The induction patterns of the promoters differed, with the upstream promoter displaying the typical stress induction of ςB-dependent promoters. Transcription initiating at SA, but not at SB, was also induced after treatment with hydrogen peroxide or puromycin. Such a double control of stress induction at two different promoters seems to be typical of a subgroup of class III heat shock genes of B. subtilis, likeclpC, and it either allows the cells to raise the level of the antioxidant thioredoxin after oxidative stress or allows stressed cells to accumulate thioredoxin. These increased levels of thioredoxin might help stressed B. subtilis cells to maintain the native and reduced state of cellular proteins.

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Thermopile pyrometer modules are the state of the art for contactless temperature measurements in automotive applications. In such an application, the thermopile has to operate precisely in a challenging thermal environment. While the compensation of the steady state ambient temperature is a well known technique when using thermopiles for temperature measurments, transient thermal effects are still an issue. The change of the ambient temperature as well as temperature flow through the sensor can lead to substantial errors due to unwanted thermal gradients within the device. In the thermopile chip they lead to an error signal since the measurement principle is based on quantifying thermal gradients of the chip that result from the detected IR-radiation. Thermal gradients in the cap and between the cap and the thermopile chip will lead to an exchange of heat radiation between the thermopile chip and the cap, which also leads to measurement errors. Different methods were developed that separately or in combination allow for a significant improvement of the accuracy and signal stability. The methods are based on the reduction of thermal gradients within the thermopile chip and the entire sensor device (isothermal, high thermal mass cap), reduction of radiation exchange between the sensor chip and the housing (low emissive inner cap surface) and prediction and software compensation of the error signal.

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