PERIOD phosphoclusters control temperature compensation of the Drosophila circadian clock

Temperature compensation is a critical feature of circadian rhythms, but how it is achieved remains elusive. Here, we uncovered the important role played by the Drosophila PERIOD (PER) phosphodegron in temperature compensation. Using CRISPR-Cas9, we introduced a series of mutations that altered three Serines (S44, 45 and 47) belonging to the PER phosphodegron, the functional homolog of mammalian PER2’s S487 phosphodegron, which impacts temperature compensation. While all three Serine to Alanine substitutions lengthened period at all temperatures tested, temperature compensation was differentially affected. S44A and S45A substitutions caused decreased temperature compensation, while S47A resulted in overcompensation. These results thus reveal unexpected functional heterogeneity of phosphodegron residues in thermal compensation. Furthermore, mutations impairing phosphorylation of the per^s phosphocluster decreased thermal compensation, consistent with its inhibitory role on S47 phosphorylation. Interestingly,the S47A substitution caused increased accumulation of hyper-phosphorylated PER at warmer temperatures. This finding was corroborated by cell culture assays in which S47A caused excessive temperature compensation of phosphorylation-dependent PER degradation. Thus, we show a novel role of the PER phosphodegron in temperature compensation through temperature-dependent modulation of the abundance of hyper-phosphorylated PER. Our work also reveals interesting mechanistic convergences and differences between mammalian and Drosophila temperature compensation of the circadian clock.

METHODS AND DEVICES FOR TEMPERATURE COMPENSATION IN GAS FLOW METERS

В статье рассмотрены типы средств измерения расхода газа, проведен анализ особенностей методов термокомпенсации и вопросов коррекции выходного сигнала расходомеров по температуре с помощью механических и электронных устройств компенсации. The article discusses the types of gas flow measurement tools, analyzes the features of thermal compensation methods and issues of correcting the output signal of flow meters by temperature using mechanical and electronic compensation devices.

Lightweight Thermal Compensation Technique for MEMS Capacitive Accelerometer Oriented to Quasi-Static Measurements

The application of MEMS capacitive accelerometers isimited by its thermal dependence, and each accelerometer must be individually calibrated to improve its performance. In this work, aight calibration method based on theoretical studies is proposed to obtain two characteristic parameters of the sensor’s operation: the temperature drift of bias and the temperature drift of scale factor. This method requiresess data to obtain the characteristic parameters, allowing a faster calibration. Furthermore, using an equation with fewer parameters reduces the computational cost of compensation. After studying six accelerometers, modelIS3DSH, their characteristic parameters are obtained in a temperature range between 15 ∘C and 55 ∘C. It is observed that the Temperature Drift of Bias (TDB) is the parameter with the greatest influence on thermal drift, reaching 1.3 mg/∘C. The Temperature Drift of Scale Factor (TDSF) is always negative and ranges between 0 and −400 ppm/∘C. With these parameters, the thermal drifts are compensated in tests with 20 ∘C of thermal variation. An average improvement of 47% was observed. In the axes where the thermal drift was greater than 1 mg/∘C, the improvement was greater than 80%. Other sensor behaviors have also been analyzed, such as temporal drift (up to 1 mg/h for three hours) and self-heating (2–3 ∘C in the first hours with the corresponding drift). Thermal compensation has been found to reduce the effect of theatter in the first hours after power-up of the sensor by 43%.

Investigation of Mechanical Strains in Thermal Compensation Loop of Superconducting NbTi Cable during Bending and Cyclic Operation

In the paper, the thermal compensation loops on a composite, superconducting NbTi cable were investigated. This type of cable is used in the superconducting, fast ramping magnets of the SIS100 synchrotron, part of the Facility for Antiproton and Ion Research (FAIR) under construction in Darmstadt, Germany. The influence of space restrictions and electromagnetic cross-talk on the design of the thermal compensation loop was discussed. Plastic deformation of cable components during bending was analyzed by numerical simulations and experiments. A three-dimensional numerical model of the cable was prepared with individual superconducting wires in contact with a central cooling pipe. The bending of a straight cable into a compensation loop shape was simulated, followed by cyclic operation of the cable during thermal cycles. The maximum strains in the superconducting strands and cooling tube were analyzed and discussed.