Analysis of Data to Evaluate the Performance of Air Filters Used for Filtering Nanoscale Particles Generated by Smoke

The main goal of this research project is to determine the effectiveness of commercially available air filters and to compare different kinds of commercially available air filters in certain categories. With recent record-breaking wildfires and the Covid-19 pandemic, research on the effects and features of nanoparticles has become increasingly important. Inhalation of nanoparticles in smoke can result in severe health effects on humans, affecting especially the respiratory system. As nanoparticles can pass through cell membranes, absorption occurs rapidly and affects many different parts and functions of the human body. While air filters are an effective method of reducing small-sized particles in flowing air, current filtration standards only apply to larger scaled microparticles, and filtration efficiencies for nanoparticles are often unknown. A good understanding of the effectiveness of air filters and masks is crucial to prevent inhalation of nanoparticles. Using a wind tunnel and two different types of woodsmokes, the penetration rates of nanoparticles through air filters were determined. Tests were performed with four different air filters using woodsmoke from hickory and applewood pallets. Due to outliers affecting mean and standard deviation values, a JavaScript code was written to eliminate outliers from the data sets. Trials with hickory smoke provided more consistent results than with applewood smoke. Average filtration effectiveness using hickory smoke was relatively close for all air filters at around 50%. Results from applewood smoke were relatively inconsistent. Due to a wide range of data and high standard deviations, effectiveness could not be established precisely

Partially Observable Concurrent Kleene Algebra

We introduce partially observable concurrent Kleene algebra (POCKA), an algebraic framework to reason about concurrent programs with variables as well as control structures, such as conditionals and loops, that depend on those variables. We illustrate the use of POCKA through concrete examples. We prove that POCKA is a sound and complete axiomatisation of a model of partial observations, and show the semantics passes an important check for sequential consistency

Kleene algebra with observations

Kleene algebra with tests (KAT) is an algebraic framework for reasoning about the control flow of sequential programs. Generalising KAT to reason about concurrent programs is not straightforward, because axioms native to KAT in conjunction with expected axioms for concurrency lead to an anomalous equation. In this paper, we propose Kleene algebra with observations (KAO), a variant of KAT, as an alternative foundation for extending KAT to a concurrent setting. We characterise the free model of KAO, and establish a decision procedure w.r.t. its equational theory

Partially Observable Concurrent Kleene Algebra

We introduce partially observable concurrent Kleene algebra (POCKA), an algebraic framework to reason about concurrent programs with variables as well as control structures, such as conditionals and loops, that depend on those variables. We illustrate the use of POCKA through concrete examples. We prove that POCKA is a sound and complete axiomatisation of a model of partial observations, and show the semantics passes an important check for sequential consistency

Regulation of haemopoietic stem‐cell proliferation in mice carrying the Slj allele

We investigated a haemopoietic stromal defect, in mice heterozygous for the Slj allele, during haemopoietic stress induced by treatment with bacterial lipopolysaccharides (LPS) or lethal total body irradiation (TBI) and bone‐marrow cell (BMC) reconstitution. Both treatments resulted in a comparable haemopoietic stem cell (CFU‐s) proliferation in Slj/+ and +/+ haemopoietic organs. There was no difference in committed haemopoietic progenitor cell (BFU‐e and CFU‐G/M) kinetics after TBI and +/+ bone‐marrow transplantation in Slj/+ and +/+ mice. the Slj/+ mice were deficient in their ability to support macroscopic spleen colony formation (65% of +/+ controls) as measured at 7 and 10 days after BMC transplantation. However, the Slj/+ spleen colonies contained the same number of BFU‐E and CFU‐G/M as colonies from +/+ spleens, while their CFU‐s content was increased. On day 10 post‐transplantation, the macroscopic ‘missing’ colonies could be detected at the microscopic level. These small colonies contained far fewer CFU‐s than the macroscopic detectable colonies. Analysis of CFU‐s proliferation‐inducing activities in control and post‐LPS sera revealed that Slj/+ mice are normal in their ability to produce and to respond to humoral stem‐cell regulators. We postulate that Slj/+ mice have a normal number of splenic stromal ‘niches’ for colony formation. However, 35% of these niches is defective in its proliferative support. Copyrigh