Large organellar changes occur during mild heat shock in yeast

When the temperature is increased, the heat shock response is activated to protect the cellular environment. The transcriptomics and proteomics of this process are intensively studied, while information about how the cell responds structurally to heat stress is mostly lacking. Here, Saccharomyces cerevisiae were subjected to a mild continuous heat shock (38°C) and intermittently cryo-immobilized for electron microscopy. Through measuring changes in all distinguishable organelle numbers, sizes, and morphologies in over 2100 electron micrographs a major restructuring of the cell's internal architecture during the progressive heat shock was revealed. The cell grew larger but most organelles within it expanded even more, shrinking the volume of the cytoplasm. Organelles responded to heat shock at different times, both in terms of size and number, and adaptations of certain organelles’ morphology (such as the vacuole), were observed. Multivesicular bodies grew to almost 170% in size, indicating a previously unknown involvement in the heat shock response. A previously undescribed electron translucent structure accumulated close to the plasma membrane. This all-encompassing approach provides a detailed chronological progression of organelle adaptation throughout the cellular heat-stress response.

Influence of Piping on On-Line Continuous Weighing of Materials inside Process Equipment: Theoretical Analysis and Experimental Verification

Due to the continuity and complexity of chemical systems, piping and operating conditions will have a significant effect on the on-line continuous weighing of materials inside process equipment. In this paper, a mathematical model of the weighing system considering piping and operating conditions was established based on the gas–liquid continuous heat transfer weighing process. A theoretical criterion which can be extended to any continuous weighing system of the materials inside equipment with connected piping is obtained through the mechanical derivation between the material mass, the cantilever beam deflection, the strain gage deformation, and the bridge output voltage. This criterion can effectively predict the influence of piping on weighing results with specific accuracy, and provide a basis for engineering optimization design. On this basis, a set of gas–liquid continuous contact weighing devices was built. The static/dynamic experimental results showed that the accuracy of the system meets the set requirements.

Experimental Study on Thermal Performance of a Loop Heat Pipe with Different Working Wick Materials

In loop heat pipes (LHPs), wick materials and their structures are important in achieving continuous heat transfer with a favorable distribution of the working fluid. This article introduces the characteristics of loop heat pipes with different wicks: (i) sintered stainless steel and (ii) ceramic. The evaporator has a flat-rectangular assembly under gravity-assisted conditions. Water was used as a working fluid, and the performance of the LHP was analyzed in terms of temperatures at different locations of the LHP and thermal resistance. As to the results, a stable operation can be maintained in the range of 50 to 520 W for the LHP with the stainless-steel wick, matching the desired limited temperature for electronics of 85 °C at the heater surface at 350 W (129.6 kW·m−2). Results using the ceramic wick showed that a heater surface temperature of below 85 °C could be obtained when operating at 54 W (20 kW·m−2).

Working Productivity Analysis on the Process of Drying Fish Using Solar Dryers

The process of drying fish using solar energy is strongly influenced by weather conditions. Sunlight is needed by household scale workers because it is cheap. On the other hand, sun drying creates additional workload for workers. Workers are exposed to hot sun during drying. Continuous heat exposure results in an increased work pulse. This affects the level of worker productivity. To anticipate this, a solar dryer is used by utilizing a solar collector as an absorber of sunlight and a drying chamber for the drying process of fish. The use of solar dryers has been shown to increase drying temperatures and reduce workers' sun exposure. This decreases the workload of workers, so that it has an impact on increasing productivity. Worker productivity increased by 133.94%.

Large Organellar Changes Occur during Mild Heat Shock in Yeast

When the temperature is increased, the heat shock response is activated to protect the cellular environment. The transcriptomics and proteomics of this process are intensively studied, while information about how the cell responds structurally to heat stress is mostly lacking. Here, Saccharomyces cerevisiae were subjected to a mild continuous heat shock and intermittently cryo-immobilized for electron microscopy. Through measuring changes in all distinguishable organelle numbers, sizes, and morphologies in over 2400 electron micrographs a major restructuring of the cell’s internal architecture during the progressive heat shock was revealed. The cell grew larger but most organelles within it expanded even more. Organelles responded to heat shock at different times, both in terms of size and number, and adaptations of certain organelles’ morphology were observed. Multivesicular bodies grew to almost 170% in size, indicating a previously unknown involvement in the heat shock response. A previously undescribed electron translucent structure accumulated close to the plasma membrane during the entire time course. This all-encompassing approach provides a detailed chronological progression of organelle adaptation throughout the cellular stress response.Summary statementExposure to mild heat shock leads to large quantifiable changes in the cellular ultrastructure of yeast, shows involvement of MVBs in the heat shock response and the apparition of novel structures.