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Bee body mass, pathogens and local climate influence heat tolerance - 1 views

  • "But few studies have examined biotic impacts, such as pathogen infection, on thermal tolerance in natural populations in combination with abiotic factors," she explained.
  • examined bee physical traits—such as sex differences in body mass—to understand how these traits interact with environmental conditions, pathogens and other factors
  • They found that variation in heat tolerance was influenced by size, sex and infection status of the bees. "Small-bodied, ectothermic—or cold-blooded—insects are considered to be highly vulnerable to changing climate because their ability to maintain proper body temperature depends on external conditions,"
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  • researchers hypothesized that the bees' heat tolerance would increase with body size; that male heat tolerance would increase with ambient temperatures above ground whereas female heat tolerance would increase with sandier soils; and that parasite infection would reduce heat tolerance
  • To test these hypotheses, the researchers collected squash bees from 14 sites across Pennsylvania that varied in mean temperature, precipitation and soil texture. They measured individuals' critical thermal maximum—the temperature above which an organism cannot function—as a proxy for heat tolerance
  • Although both sexes showed a positive correlation between heat tolerance and size, male squash bees had a greater change in their critical thermal maximum per unit body mass than females, suggesting that there may be another biological trait influencing the impact of body mass on heat tolerance that differs between the sexes
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    There is a strong feasibility element to this sort of work. Being invertebrates, there would be no problem collecting large numbers of bees from the environment for testing. Now... how that is typically done in other research studies... is something to dig into. The challenge here would be the observation/measurement of parasites (like the trypanosomes mentioned here). It might be worth digging into microdissection methods and techniques that others have reported on when working with pollinators and other small insects. It might not be impossible, even in our lab, but it would definitely be a (good) challenge and perhaps something we could find an expert to help us with.
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Common plastics could passively cool and heat buildings with the seasons | ScienceDaily - 0 views

  • Researchers at Princeton and UCLA have developed a passive mechanism to cool buildings in the summer and warm them in the winter.
  • coatings engineered from common materials can achieve energy savings and thermal comfort that goes beyond what traditional building envelopes can achieve
  • "With the increase in global temperatures, maintaining habitable buildings has become a global challenge,"
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  • "In recent years there has been massive interest in cool roof coatings that reflect sunlight. But cooling walls and windows is a much more subtle and complex challenge."
  • "By coating walls and windows with materials that only radiate or absorb heat in the atmospheric window, we can reduce broadband heat gain from the ground in the summer, and loss in the winter, while maintaining the cooling effect of the sky. We believe that this idea is unprecedented, and beyond what traditional roof and wall envelopes can achieve."
  • The findings' impact is significant for two important reasons. First, the researchers show in the article that many common and low-cost building materials radiate heat in the narrowband and block broadband heat. Material such as polyvinyl fluoride, already used as siding material, could be adapted for the purpose, as could even more common plastics.
    • Sean Nash
       
      Smells like feasibility....
  • "We were really excited when we found that materials like Polypropylene, which we sourced from household plastics, selectively radiate or absorb heat in the atmospheric window." Raman noted. "These materials border on the mundane, but the same scalability that makes them common also means that we could see them thermoregulating buildings in the near future."
  • The second reason for optimism is that the potential energy impacts at the building scale are substantial. The researchers noted that seasonal energy savings with their mechanism are comparable to the benefits of painting dark roofs white. This could be useful as air conditioning cost and heat related casualties continue to soar worldwide. Mandal and Raman plan to continue this research further.
  • "The mechanism we proposed is completely passive, which makes it a sustainable way to cool and heat buildings with the seasons and yield untapped energy savings."
  • Journal Reference: Jyotirmoy Mandal, Jyothis Anand, Sagar Mandal, John Brewer, Arvind Ramachandran, Aaswath P. Raman. Radiative cooling and thermoregulation in the earth’s glow. Cell Reports Physical Science, 2024; 102065 DOI: 10.1016/j.xcrp.2024.102065
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    Don't know if you're following changes in climate, but... this might be an area for some engineering. What are the other problems involved with this field of study? Interesting to anyone?
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Microwaving an insecticide restores its mosquito-killing power - 1 views

  • Heating an insecticide can give it new life.
    • Sean Nash
       
      Wait... what?
  • Microwaving the insecticide deltamethrin rearranges its crystal structure but doesn’t change its chemical composition. The rearrangement renews deltamethrin’s ability to kill mosquitoes that have become resistant to the insecticide, researchers report April 21 in Malaria Journal.
    • Sean Nash
       
      Seems like potential feasibility
  • The microwave worked just as well, but Kahr cautions that people shouldn’t use the same microwave for heating food and insecticides.
    • Sean Nash
       
      Ha! Oh really??
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  • insecticide resistance is a growing problem
  • “There are all kinds of social and cultural things that you could propose from a scientific perspective that wouldn’t be welcomed by a community of homeowners.”
    • Sean Nash
       
      Another positive...
  • It’s not certain that the heat-treated deltamethrin would retain its more potent crystal structure through the net-making process.
  • Kahr’s team is working on incorporating the heat-treated crystal into nets.
  • It is encouraging that heated insecticide killed highly resistant mosquitoes, says Hemingway, who directs the Infection Innovation Consortium, a public-private effort to find new ways to combat infectious diseases. But, she says, “this is not something we can take and use that tomorrow.”
    • Sean Nash
       
      OK.... this is how you can find an opening (not saying THIS ONE is necessarily, but, when you see language like: "we can't really do it just yet," that is a screaming opportunity to see what we MIGHT be able to add to that. We would just want to get early approval from the fair re: hazardous substances. I think we could.
  • Kahr and colleagues previously discovered that heating deltamethrin changed its crystal structure, which let it work faster
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    "Wait, what? Do say more....."
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New fabric cools people in sweltering cities - 0 views

  • researchers have designed a new wearable fabric to help people beat the heat in urban settings. The material, reported in the journal Science, could find use in clothing, cooling facades for buildings and cars, and for food storage and transport.
  • Existing cooling fabrics reflect sunlight and also wick away sweat to cool a person via evaporation. More recently, researchers have designed cooling fabrics that rely on the principle of radiative cooling: the natural phenomenon in which objects radiate heat through the atmosphere straight into outer space.
  • But radiative cooling fabrics made so far are designed to work when laid horizontally as opposed to vertically, as they would be when worn.
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  • researchers at the University of Chicago made a new three-layer fabric. Its wool bottom layer wicks heat from the skin to the middle layer, which is made of silver nanowires that block heat from coming in. The top layer selectively emits heat into the atmosphere.
  • In tests conducted in the urban heat island of Chicago and under blistering Arizona sun, the material stayed 2.3°C cooler than sports cooling fabrics and 8.9°C cooler than commercial silk used for summer clothing.
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    Materials science is certainly a nifty bit of engineering. This is the second time I've seen this study mentioned. Look interesting enough to dig into various materials and how they might be combined to serve a key purpose?
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New fabric makes urban heat islands more bearable | ScienceDaily - 0 views

  • This year has already seen massive heatwaves around the globe, with cities in Mexico, India, Pakistan and Oman hitting temperatures near or past 50 degrees Celsius (122 degrees Fahrenheit).
  • In tests under the Arizona sun, the material kept 2.3 degrees Celsius (4.1 degrees Fahrenheit) cooler than the broadband emitter fabric used for outdoor endurance sports and 8.9 degrees Celsius (16 degrees Fahrenheit) cooler than the commercialized silk commonly used for shirts, dresses and other summer clothing.
  • "You can save a lot of cooling, electricity and energy costs because this is a passive process," Sui said.
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  • Spectrally engineered textile for radiative cooling against urban heat islands. Science, 2024; 384 (6701): 1203 DOI: 10.1126/science.adl0653
    • Sean Nash
       
      I'm not yet convinced of the feasibility of this one, but this might provide a spark for someone. Some types of materials engineering like this is done on a nanoscale, which may not be the best for what we can do... but I believe there is space here for exploring composite materials with different properties to engineer better outcomes than what we're currently dealing with.
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    "With applications in clothing, construction and food storage, the new textile reduces heat from both the sun and thermal radiation from nearby buildings"
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