Housing-related determinants of lung health in Nunavik, Canada

The impact of climate change on lung health has been long established. The Inuit Nunangat region of Nunavik in Quebec, Canada has long started to face the consequences of climate change. In conjunction with the region’s existing vulnerabilities rooted in social determinants of health and historic injustices, this leads to poor lung health across Nunavik as evidenced by much higher lung disease rates than the Canadian average. This paper aims to describe the aims, objectives and methodology of a new project that has recently been launched to address these issues with specific emphasis on mould detection as well as indoor and building fabric survey: “Resilient Responses to Protect Lung Health in Nunavik” (Anirniq, 2022-2025) funded as part of the Canada-Inuit Nunangat-United Kingdom (CINUK) Arctic Research Programme

Cancer Biomarker Discovery: The Entropic Hallmark

Background: It is a commonly accepted belief that cancer cells modify their transcriptional state during the progression of the disease. We propose that the progression of cancer cells towards malignant phenotypes can be efficiently tracked using high-throughput technologies that follow the gradual changes observed in the gene expression profiles by employing Shannon's mathematical theory of communication. Methods based on Information Theory can then quantify the divergence of cancer cells' transcriptional profiles from those of normally appearing cells of the originating tissues. The relevance of the proposed methods can be evaluated using microarray datasets available in the public domain but the method is in principle applicable to other high-throughput methods. Methodology/Principal Findings: Using melanoma and prostate cancer datasets we illustrate how it is possible to employ Shannon Entropy and the Jensen-Shannon divergence to trace the transcriptional changes progression of the disease. We establish how the variations of these two measures correlate with established biomarkers of cancer progression. The Information Theory measures allow us to identify novel biomarkers for both progressive and relatively more sudden transcriptional changes leading to malignant phenotypes. At the same time, the methodology was able to validate a large number of genes and processes that seem to be implicated in the progression of melanoma and prostate cancer. Conclusions/Significance: We thus present a quantitative guiding rule, a new unifying hallmark of cancer: the cancer cell's transcriptome changes lead to measurable observed transitions of Normalized Shannon Entropy values (as measured by high-throughput technologies). At the same time, tumor cells increment their divergence from the normal tissue profile increasing their disorder via creation of states that we might not directly measure. This unifying hallmark allows, via the the Jensen-Shannon divergence, to identify the arrow of time of the processes from the gene expression profiles, and helps to map the phenotypical and molecular hallmarks of specific cancer subtypes. The deep mathematical basis of the approach allows us to suggest that this principle is, hopefully, of general applicability for other diseases

Impact of room supply register location on predicted thermal comfort and IAQ

For residential forced air heating and cooling systems conventional thinking is that air supply registers should be located under exterior windows. There were good reasons for this in the past (primarily to counteract the cold downdraught from the window) but new construction standards (well-insulated walls, better glazing and air tight wall/window interface) mean that there is now less downdraught. Positioning the supply air register away from a window could have a large impact for new construction as duct lengths could be shortened (saving materials and construction time). This could also allow greater architectural freedom as the forced air system would not need to be ducted to the building perimeter. This paper presents results from experiments conducted in a new, well-constructed building to evaluate whether the supply registers can be moved away from the traditional location without impacting indoor air quality or predicted thermal comfort. The physical experiments showed that in both traditional and non-traditional placement: (1) there are minimal changes in predicted thermal comfort (a measure of thermal discomfort - vertical air temperature difference much lower than 3K), and (2) contaminant-removal effectiveness (a measure of indoor air quality) values were in the same range.Peer reviewed: YesNRC publication: Ye

Making the case for reducing ventilation requirements through selection of low-emission materials

Most ventilation rates have not been based on pollutants emitted from building materials and furnishings. Anapproach using the existing Material Emission Database and Indoor Air Quality computer model is presented. The approach examines by how much ventilation rates can be reduced through control of indoor sources of air pollutants while still maintaining acceptable IAQ for residential settings and the consequences on indoor air contaminant concentrations of reductions in ventilation rates below current design requirements.La plupart des valeurs de taux de renouvellement d'air n'ont pas \ue9t\ue9 fond\ue9es sur les agents polluants qui sont \ue9mis par les mat\ue9riaux et les ameublements des b\ue2timents. On pr\ue9sente une m\ue9thode utilisant le mod\ue8le existant de qualit\ue9 de l'air \ue0 l'int\ue9rieur existant et de base de donn\ue9es sur les \ue9missions de substances. Dans le cadre de cette approche, on examine dans quelle mesure les taux de renouvellement d'air peuvent \ueatre r\ue9duits par le contr\uf4le des sources int\ue9rieures d'agents polluants atmosph\ue9riques tout en maintenant une QAI acceptable dans les milieux r\ue9sidentiels, ainsi que les cons\ue9quences sur les concentrations \ue0 l'int\ue9rieur des agents contaminants qu'a une r\ue9duction des taux de renouvellement d'air en de\ue7\ue0 des exigences nominales ayant cours.Peer reviewed: YesNRC publication: Ye

Air change effectiveness with displacement ventilation in heating season

Peer reviewed: YesNRC publication: Ye

Hybrid ventilation

Aussi disponible en fran\ue7ais: Ventilation hybridePeer reviewed: NoNRC publication: Ye

In-situ performance of displacement ventilation system in Canadian schools with radiant heating systems

Previous research has shown that stratified ventilation systems (UFAD and DV) work well for regions where buildings require year-round cooling; however there are a growing number of buildings using this approach in Canada, where buildings require heating during winter months. This paper presents results from two field studies conducted in a school equipped with a combination of displacement ventilation and radiant heating system. The results show that the measured contaminant removal effectiveness is better than that predicted in previous studies for heating conditions. In addition, key predictors of thermal comfort are also generally within limits set by ASHRAE standards.Les recherches ant\ue9rieures ont d\ue9montr\ue9 que les syst\ue8mes de ventilation stratifi\ue9e (distribution d?air \ue0 sous-\ue9coulement [UFAD] et ventilation par circulation [DV]) fonctionnent efficacement dans les r\ue9gions o\uf9 il est n\ue9cessaire de climatiser les b\ue2timents \ue0 longueur d?ann\ue9e. Cependant, on note que de plus en plus de b\ue2timents utilisent cette approche au Canada, o\uf9 il est n\ue9cessaire de chauffer les b\ue2timents durant l?hiver. Ce document pr\ue9sente les r\ue9sultats provenant de deux (2) \ue9tudes in situ r\ue9alis\ue9es dans une \ue9cole dot\ue9e d?une combinaison de syst\ue8me DV et de syst\ue8me de chauffage du type rayonnant. Les r\ue9sultats indiquent que l?efficacit\ue9 mesur\ue9e de cette installation en termes d?\ue9limination des agents contaminants est sup\ue9rieure \ue0 celle pr\ue9dite dans le cadre des \ue9tudes ant\ue9rieures pour les conditions de chauffage. En outre, les variables explicatives cl\ue9s du confort thermique sont elles-aussi g\ue9n\ue9ralement comprises \ue0 l?int\ue9rieur des limites fix\ue9es par les normes ASHRAE.Peer reviewed: YesNRC publication: Ye

Hybrid heating

Aussi disponible en fran\ue7ais: Chauffage hybridePeer reviewed: NoNRC publication: Ye