On assuming Mean Radiant Temperature equal to air temperature during PMV-based thermal comfort study in air-conditioned buildings

Mean Radiant Temperature (MRT) is an important factor of Fanger's PMV model, which is the most popular method to study human thermal comfort. However, it has often been a practice to assume MRT equal to air temperature (Ta) during indoor thermal studies. In this paper, we have studied the consequences of this simplistic assumption on the thermal comfort of occupants in air-conditioned buildings. A worldwide database of about 10000 occupants covering 9 climatic zones and 4 seasons has been studied. The effect on comfort indices-Predicted Mean Vote (PMV), Actual Mean Vote (AMV), Thermal Acceptability Vote (TSA) and Thermal Preference Vote (MCI) are presented. It is observed that even a small difference in Ta and MRT can lead to significant error in determination of thermal comfort. A correlation study between AMV and the six Macpherson factors reveals that MRT has the highest positive correlation with the thermal sensation reported by the occupants. Study of TSA and MCI show that the assumption is more likely to affect comfort level determination in the uncomfortable range.NRF (Natl Research Foundation, S’pore)Accepted versio

Structural and mechanistic insights into the function of Leishmania ribosome lacking a single pseudouridine modification

International audienceLeishmania is the causative agent of cutaneous and visceral diseases affecting millions of individuals worldwide. Pseudouridine (Ψ), the most abundant modification on rRNA, changes during the parasite life cycle. Alterations in the level of a specific Ψ in helix 69 (H69) affected ribosome function. To decipher the molecular mechanism of this phenotype, we determine the structure of ribosomes lacking the single Ψ and its parental strain at ∼2.4–3 Å resolution using cryo-EM. Our findings demonstrate the significance of a single Ψ on H69 to its structure and the importance for its interactions with helix 44 and specific tRNAs. Our study suggests that rRNA modification affects translation of mRNAs carrying codon bias due to selective accommodation of tRNAs by the ribosome. Based on the high-resolution structures, we propose a mechanism explaining how the ribosome selects specific tRNAs