Spontaneous pneumothorax as a manifestation of COVID-19: A case report

Spontaneous pneumothorax (SP) is an uncommon complication of COVID-19, mostly in association with pre-existing lung conditions or under positive pressure ventilation. SP has been reported to occur in approximately 1% of the patients with COVID-19. We report here a case of a 47-year-old non-smoker gentleman without any pre-existing lung disease, who was admitted to our facility with fever, cough and shortness of breath and for 3 days with progressive worsening and chest pain over last 24 hours. Chest radiography revealed the diagnosis of right-sided pneumothorax with widespread patchy infiltrates on the left lung field. He was tested positive for COVID-19 and cultures for secondary bacterial infections were negative. A chest drain was secured and he was given antibiotics, steroid, heparin and remdesivir. However, the patient died within next 2 days due to progressive respiratory failure. This report emphasizes awareness of the possibility of SP as a complication of COVID-19; early identification and treatment of this entity may help decrease the associated mortality and morbidity. In conclusion, the possibility of SP should always be considered in the workup of a patient of SARS-CoV-2 infection having acute shortness of breath with or without chest pain. We would like to highlight this significant, though rare, presentation of COVID-19 and urge clinicians to maintain a high index of suspicion

miRNA gene counts in chromosomes vary widely in a species and biogenesis of miRNA largely depends on transcription or post-transcriptional processing of coding genes

MicroRNAs target specific mRNA(s) to silence its expression and thereby regulate various cellular processes. We have investigated miRNA gene counts in chromosomes for 20 different species and observed wide variation. Certain chromosomes have extremely high number of miRNA gene compared with others in all the species. For example, high number of miRNA gene in X chromosome and the least or absence of miRNA gene in Y chromosome was observed in all species. To search the criteria governing such variation of miRNA gene counts in chromosomes, we have selected three parameters- length, number of non-coding and coding genes in a chromosome. We have calculated Pearson’s correlation coefficient of miRNA gene counts with length, number of non-coding and coding genes in a chromosome for all 20 species. Major number of species showed that number of miRNA gene was not correlated with chromosome length. 85% of species under study showed strong positive correlation coefficient (r≥0.5) between the numbers of miRNA gene vs non-coding gene in chromosomes as expected because miRNA is a sub-set of non-coding genes. 55% species under study showed strong positive correlation coefficient (r≥0.5) between numbers of miRNA gene vs coding gene. We hypothesize biogenesis of miRNA largely depends on coding genes, an evolutionary conserved process. Chromosomes having higher number of miRNA genes will be most likely playing regulatory roles in several cellular processes including different disorders. In humans, cancer and cardiovascular disease associated miRNAs are mostly intergenic and located in Chromosome 19, X, 14 and 1

Synchronization of Time Delayed Systems by Common Delay Time Modulations

We investigate the synchronization phenomenon between two identical time delayed systems with the common time delay, modulated by a chaotic or random signal. The phenomenon is verified by the conditional Lyapunov exponent. The relation between the present form of synchronization with generalized one is also discussed

Cold Bubble Humidification of Oxygen: Old habits die hard

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Physical and mechanical properties of Albizia procera glulam beam

This research was done to evaluate the feasibility of using Albizia procera for manufacturing glulam beams. The physical and mechanical properties of the A. procera glulam beam were evaluated, and these properties were compared to those of the solid A. procera solid timber. The A. procera glulam beam’s physical and mechanical properties were all superior to solid A. procera timber. In comparison to A. procera solid timber, A. procera glulam’s density, water absorption (WA), linear expansion (LE), and thickness swelling (TS) all improved by 11.1, 48.4, 44.6, and 37.0%, respectively. Again, compared to A. procera solid timber, the modulus of rupture (MOR) and modulus of elasticity (MOE) of the A. procera glulam beam increased by 27.6 and 29.2%, respectively. Additionally, the ASTM specifications were met by the A. procera glulam beam. As a result, based on the properties, it is possible to make A. procera glulam beams as structural timber products

Investigating the drying characteristics of Anthocephalus chinensis (Lam.) A. Rich ex Walp wood

Anthocephalus chinensis (Lam.) A. Rich ex Walp is widely used as raw materials in particleboard and match industries in Bangladesh. The current study aimed to identify the drying characteristics of A. Chinensis wood for succeeding industrial usages. A compartment kiln dryer (heat and vent dryer) was used in this study. The drying characteristics and drying quality of A. Chinensis wood were measured. The boards reached 6–10% moisture content in 13 days from their green condition. The total proportions of the check, twist, and collapse in boards were 22.5, 32.5, and 7.3%, respectively. The volumetric shrinkage was 21.67%. Based on this study, further study may help to develop a complete drying schedule of A. Chinensis wood with fewer drying defects for application at industrial level