“A good ratio of oxygen to methane is key to combustion,” said Justin Long.
Can methane flare burners be advanced to produce less methane? This is what a recent study published in Industrial & Engineering Chemistry Research hopes to address as a team of researchers from the University of Michigan (U-M) and the Southwest Research Institute (SwRI) developed a methane flare burner with increased combustion stability and efficiency compared to traditional methane flare burners. This study has the potential to develop more environmentally friendly burners to combat human-caused climate change, specifically since methane is a far larger contributor to climate change than carbon dioxide.
For the study, the researchers used a combination of machine learning and novel manufacturing methods to test several designs of a methane flare burner that incorporates crosswinds to simulate real-world environments. The burner design includes splitting the methane flow in three directions while enabling oxygen flow from crosswinds to mix with the methane, enabling a much cleaner combustion. In the end, the researchers found that their design achieves 98 percent combustion efficiency, meaning it produces 98 percent less methane than traditional burners.
“A good ratio of oxygen to methane is key to combustion,” said Justin Long, who is a Senior Research Engineer at SwRI. “The surrounding air needs to be captured and incorporated to mix with the methane, but too much can dilute it. U-M researchers conducted a lot of computational fluid dynamics work to find a design with an optimal air-methane balance, even when subjected to high-crosswind conditions.”
Georg Ferdinand Ludwig Philipp Cantor (/ ˈ k æ n t ɔːr / KAN-tor; German: [ˈɡeːɔʁk ˈfɛʁdinant ˈluːtvɪç ˈfiːlɪp ˈkantoːɐ̯] ; 3 March [O.S. 19 February] 1845 – 6 January 1918 [ 1 ] ) was a mathematician who played a pivotal role in the creation of set theory, which has become a fundamental theory in mathematics. Cantor established the importance of one-to-one correspondence between the members of two sets, defined infinite and well-ordered sets, and proved that the real numbers are more numerous than the natural numbers. Cantor’s method of proof of this theorem implies the existence of an infinity of infinities. He defined the cardinal and ordinal numbers and their arithmetic. Cantor’s work is of great philosophical interest, a fact he was well aware of. [ 2 ]
Originally, Cantor’s theory of transfinite numbers was regarded as counter-intuitive – even shocking. This caused it to encounter resistance from mathematical contemporaries such as Leopold Kronecker and Henri Poincaré [ 3 ] and later from Hermann Weyl and L. E. J. Brouwer, while Ludwig Wittgenstein raised philosophical objections; see Controversy over Cantor’s theory. Cantor, a devout Lutheran Christian, [ 4 ] believed the theory had been communicated to him by God. [ 5 ] Some Christian theologians (particularly neo-Scholastics) saw Cantor’s work as a challenge to the uniqueness of the absolute infinity in the nature of God [ 6 ] – on one occasion equating the theory of transfinite numbers with pantheism [ 7 ] – a proposition that Cantor vigorously rejected.
The results show two distinct patterns in the protective effect of natural infection against reinfection in the Omicron era compared to the pre-Omicron era. Before the emergence of Omicron, natural infection offered robust protection against reinfection, with roughly 80% effectiveness and minimal signs of waning over time after the infection. However, during the Omicron era, this protection was strong only for recently infected individuals, rapidly declining over time after the infection and ultimately diminishing within a year. These patterns were consistent regardless of whether any infection or only symptomatic infection was considered as an outcome, and for both vaccinated and unvaccinated populations.
The two distinct patterns observed in the Omicron versus pre-Omicron eras provide population-level results that validate previous experimental molecular evidence1,2,18,19,20, and are probably the result of a complex interplay of several interrelated factors, in addition to waning immunity, immune evasion and the accelerated and convergent evolution of Omicron, such as immune imprinting, varying immunogenicity, global population immunity faced by the strains and population characteristics associated with infections at different stages of the pandemic.
Whereas these factors are interconnected and challenging to disentangle, the observed differences in protection against reinfection may stem from distinct evolutionary pressures acting on SARS-CoV-2 during the pre-Omicron and Omicron eras. In the pre-Omicron era, with a large proportion of individuals remaining immune naive because of non-pharmaceutical interventions and delayed scale-up of vaccination, intrinsic transmissibility may have been the primary driver of viral adaptation. This was evidenced by the emergence of more transmissible variants such as Alpha4,22,23 and Delta24,25. Conversely, following the very large and widespread Omicron wave in early 2022 (Extended Data Fig. 3)26, most individuals possessed some level of immunity, either from infection or vaccination. This may have shifted the dominant evolutionary pressure towards immune escape through not only antigenic drift, but also recombination and convergent evolution as the adaptive mechanisms for the virus2,18,27,28.
Hippos spend 16 hours a day submerged in water. Withough Sun protection, they wouldn’t survive.
That reddish substance that sometimes appears on the skin of hippopotamuses?
That unique secretion serves as a sunscreen, protecting them from solar radiation. The secretion contains two highly acidic and unstable compounds: hipposudoric acid (red) and norhipposudoric acid (orange).
When these compounds mix with mucus and dry on the hippo’s skin, they form a durable layer that acts as a natural sunscreen, protecting the animal from harmful UV rays for hours. Hippos are semiaquatic, spending up to 16 hours a day submerged in water to stay cool, but this does not shield their skin from the sun, making their natural sunscreen essential.
Scientists believe the secretion is synthesized from amino acids when exposed to oxygen, though much about its exact mechanisms remains unknown. Recent research has revealed that the secretion, often referred to as “hippo sweat,” contains microscopic structures that scatter light, providing both sunblock and sunscreen properties. The substance also includes red and orange pigments capable of absorbing ultraviolet light, contributing to its effectiveness.
