Empirical investigation to explore potential gains from the amalgamation of Phase Changing Materials (PCMs) and wood shavings

The reduction of gained heat, heat peak shifting and the mitigation of air temperature fluctuations are some desirable properties that are sought after in any thermal insulation system. It cannot be overstated that these factors, in addition to others, govern the performance of such systems thus their effect on indoor ambient conditions. The effect of such systems extends also to Heating, Ventilation and Air-conditioning (HVAC) systems that are set up to operate optimally in certain conditions. Where literature shows that PCMs and natural materials such as wood-shavings can provide efficient passive insulation for buildings, it is evident that such approaches utilise methods that are of a degree of intricacy which requires specialist knowledge and complex techniques, such as micro-encapsulation for instance. With technical and economic aspects in mind, an amalgam of PCM and wood-shavings has been created for the purpose of being utilised as a feasible thermal insulation. The amalgamation was performed in the simplest of methods, through submerging the wood shavings in PCM. An experimental procedure was devised to test the thermal performance of the amalgam and compare this to the performance of the same un-amalgamated materials. Comparative analysis revealed that no significant thermal gains would be expected from such amalgamation. However, significant reduction in the total weight of the insulation system would be achieved that, in this case, shown to be up to 20.94%. Thus, further reducing possible strains on structural elements due to the application of insulation on buildings. This can be especially beneficial in vernacular architectural approaches where considerably large amounts and thicknesses of insulations are used. In addition, cost reduction could be attained as wood shavings are significantly cheaper compared to the cost of PCMs

Chemical and structural analysis of a photoactive vertebrate cryptochrome from pigeon

Computational and biochemical studies implicate the blue-light sensor cryptochrome (CRY) as an endogenous light-dependent magnetosensor enabling migratory birds to navigate using the Earth's magnetic field. Validation of such a mechanism has been hampered by the absence of structures of vertebrate CRYs that have functional photochemistry. Here we present crystal structures of Columba livia (pigeon) CRY4 that reveal evolutionarily conserved modifications to a sequence of Trp residues (Trp-triad) required for CRY photoreduction. In ClCRY4, the Trp-triad chain is extended to include a fourth Trp (W369) and a Tyr (Y319) residue at the protein surface that imparts an unusually high quantum yield of photoreduction. These results are consistent with observations of night migratory behavior in animals at low light levels and could have implications for photochemical pathways allowing magnetosensing

A prospective cohort study on post COVID syndrome from a tertiary care centre in Sri Lanka

Abstract There is a scarcity of follow-up data on post-COVID syndrome and its physical, psychological, and quality of life attributes, particularly from South Asian populations. This study was conducted to assess the prevalence, associations, and impact of the post-COVID syndrome among patients treated at a dedicated COVID-19 treatment unit. A prospective cohort study was conducted to follow-up patients with moderate to severe disease or mild disease with co-morbidities at 2 and 6 weeks, 3 and 6 months and 1 year from discharge. Clinical notes, an interviewer-administered questionnaire and six-item cognitive impairment, Montreal Cognitive Assessment, Fatigue (11-item Chalder) and EQ5D5L questionnaires were used for data collection. All patients had follow-up echocardiograms and symptomatic patients had biochemical and haematological investigations, chest x-rays, high-resolution computed tomography of chest and lung function tests. Among 153 patients {mean age 57.2 ± 16.3 years (83 (54.2% males)}, 92 (60.1%) got the severe disease. At least a single post-COVID symptom was reported by 119 (77.3%), 92 (60.1%), 54 (35.3%) and 25 (16.3%) at 6 weeks, 3 months, 6 months and 1 year respectively. Post-COVID symptoms were significantly associated with disease severity (p = 0.004). Fatigue was found in 139 (90.3%), 97 (63.4%) and 66 (43.1%) patients at 2, 6 and 12 weeks respectively. Dyspnoea {OR 1.136 (CI 95% 0.525–2.455)}, arthralgia {OR 1.83(CI 95% 0.96–3.503)} and unsteadiness {OR 1.34 (CI 95% 0.607–2.957)}were strongly associated with age above 60 years. Both genders were equally affected. In multivariable logistic regression, fatigue and anxiety/depression were associated with poor quality of life (QoL) (p = 0.014, p ≤ 0.001) in 6 weeks. In cardiac assessments, diastolic dysfunction (DD) was detected in 110 (72%) patients at 2 weeks and this number reduced to 64 (41.8%) at 12 weeks. The decline in diastolic dysfunction in elderly patients was significantly higher compared to young patients (p = 0.012). Most post-COVID symptoms, QoL and cognition improve during the first few months. The severity of the disease and older age are associated with post-COVID symptoms. Transient DD may contribute to cardiac symptoms of post-COVID syndrome, especially in elderly patients