Transcript

4.2.26 · Science Show KY

0:01
Speaker 1: Welcome to Radioized Diary of Science and Nature. I'm Kelly Taylor.
0:06
I'll be your reader and we have some articles related
0:10
to science and nature. But first a reminder that RADIOI
0:14
is a reading service intended for people who are blind
0:18
or have other disabilities that make it difficult to read
0:21
printed material. Starting with an article from March thirty first,
0:28
in USA today are fungal storms becoming more common. What
0:34
they are when they strike, fungi are taking the US
0:39
by storm, and not in a good way. What's being
0:42
described as fungal storms isn't a new kind of weather,
0:47
experts say, but a dangerous mix of conditions where airborne
0:51
spores hitch a ride on dust, winds and flooding. Fungi
0:56
aren't literally storming areas like rain or hail, but storms
1:00
act as the vehicle while the spores supply the threat.
1:05
As climate change drives hotter, drier, and more extreme weather,
1:09
these microscopic threats are spreading farther and becoming more resilient,
1:14
sometimes with deadly consequences. Fungal spores can spread anytimes soil
1:21
is disturbed and particles are sent into the air. Dust
1:25
Storms are the most visible driver, especially in the Southwest.
1:30
BBC Science Focus magazine reported that strong winds can lift dry,
1:35
contaminated soil into the atmosphere, sometimes forming fast moving walls
1:40
of dust known as haboobs. These clouds can sweep particles,
1:46
including fungal spores, across large distances, increasing the risk of inhalation. Quote.
1:54
Sand and dust storms do not just mean dirty windows
1:58
in hazy skies, As Secretary General of the World Meteorological
2:02
Organization Celeste Solo, quote, they harmed the health and quality
2:08
of life of millions of people and cost many millions
2:12
of dollars through disruption to air and ground transport, on agriculture,
2:18
and on solar energy production. Other triggers include heavy rain, flooding,
2:26
and mud that drives that dries afterward. Hurricane Hillary in
2:31
twenty twenty three, for example, prompted doctors in the desert
2:35
southwest to monitor for valley fever of fungal infection linked
2:40
to soil born spores. Fox Weather reported during the recovery
2:45
efforts in August of twenty twenty three, winds from monsoons,
2:51
tropical storms, and even seismic activity can lift spores, while
2:56
consistent rain and atmospheric rivers create the moistcoat conditions that
3:00
allow fungi to thrive. This sets up a repeating cycle
3:05
Wet conditions multiply spores, and the next round of high
3:09
winds spreads them farther, increasing exposure risk. Quote. I'm not
3:15
sure we can prevent people from getting valley fever, says
3:20
Christy Mitchie, assistant director of public health in California's Monterey County.
3:26
It's very difficult to avoid dust in our environment. But
3:29
what we don't want is people get really sick with
3:32
valley fever. Her community, a cool coastal agricultural region, had
3:38
just a couple of dozen cases a year in past decades,
3:42
but now average hundreds. But weather isn't the only trigger. Construction,
3:47
agriculture and wildfires can also disturb soil and release fungal
3:52
particles into the air. Once airborne, these microscopic spores are
3:57
easily inhaled without people realizing it. At the same time
4:01
that opportunities for spores to spread are increasing, the fungi
4:05
themselves are becoming more resilient. Species like Aspergillis thrive in
4:11
warmer temperatures and changing environmental conditions, and widespread use of
4:16
azol compounds in agriculture and medicine is driving drug resistance.
4:22
This allows some fungi to survive longer and spread more easily,
4:26
raising the risk of severe infections. Fungal infections tied to
4:32
airborne spores remain most common in the Southwest, particularly in
4:37
dry regions of Arizona, California, New Mexico, and Texas, where
4:41
these organisms naturally live in the soil. In the United States,
4:46
illnesses linked to these fungi, most notably valley fever, are
4:51
still concentrated in that region, making it the primary hotspot
4:55
for exposure, but that footprint is expanding. Cases are a
5:00
increasingly being identified outside the Southwest, including in states like
5:04
Oregon and Washington, suggesting the geographic range is shifting. According
5:10
to earth dot Com, species like Aspergillis are moving into
5:14
areas that were previously inhospitable as warmer temperatures and changing
5:19
moisture patterns reshape where they can survive. Quote We've already
5:26
seen the emergence of the fungus Candida orus due to
5:30
rising temperatures, but until now we had little information on
5:33
how other fungi might respond to this change in the environment,
5:37
says doctor Norman Van Rhine at the University of Manchester.
5:43
The result is a widening risk zone, while the Southwest
5:47
remains ground zero. Experts warrant exposure could spread farther into
5:51
the Midwest and even parts of Canada in the coming decades.
5:56
Several fungal species are most often carried by dust and
5:59
other soil disturbances, posing health risks when inhaled. The key
6:04
players include Cucidoides species responsible for valley fever, found mainly
6:10
in the dry soils of the US Southwest. Spores become
6:14
airborne when soil is disturbed. Aspergillis species includes A fumigatus
6:22
and A flavus, which thrive in warm, humid soils and
6:28
decaying vegetation. Airborne spores can travel long distances and infect lungs.
6:35
Histoplasma capsulatum common in soils enriched with bird or bat droppings.
6:42
Disturbances such as construction flooding can send spores into the air,
6:46
and Blastomyces dermatitis found in moist soils and near water bodies.
6:52
The spores can spread when soil is churned by storms, floods,
6:56
or human activity. Of these, cocid dioil and Aspergillis are
7:02
generally the most dangerous to humans that can cause severe
7:05
pulmonary disease, and especially in drug resistant strains, that can
7:11
lead to life threatening infections in people with weakened immune systems.
7:16
Most fungi are harmless. In fact, many are beneficial, helping
7:20
decompose organic matter, recycled nutrients, or even make food like mushrooms, bread,
7:25
and cheese. Only a small fraction of species can make
7:29
humans sick, and serious infections are usually limited to people
7:32
with weakened immune systems. The fungi that pose the greatest
7:36
threat during so called fungal storms are soil born or
7:39
airborne pathogens. While these species are dangerous, they represent a
7:44
tiny fraction of the fungal world. Now we'll turn over
7:50
to Scientific American. This is from March twenty ninth, The
7:56
surprisingly baffling science of static electricity. This familiar phenomenon has
8:04
published researchers for centuries, but experiments are finally making sense
8:08
of its unruly behaviors. Static electricity is so commonplace that
8:13
it can come across as simple. Rub a balloon against
8:16
your head and the transfer of charges will make your
8:18
hair stand on end. Shuffle your feet on a carpet,
8:22
and the charge imbalance you produce can shock an innocent passerby.
8:27
So it might come as a surprise that static electricity,
8:30
which arises from what researchers in the field call the
8:33
triboelectric effect, has left scientists racking their brains for centuries.
8:40
Some of the basics are clear. Materials transfer charges when
8:44
they're rubbed or otherwise come into contact with each other.
8:48
One becomes more positively charged and the other more negatively charged.
8:52
Opposite charges attract, whereas identical charges repel and tara you
8:57
have a primary school science experiment, but most everything else
9:01
in this field remains baffling. Is it the electrons, ions,
9:06
or bits of material that transfer the charge? Why do
9:10
some materials charge positively and others negatively? What happens when
9:15
two samples of the same material come into contact, for example,
9:18
when rubbing a balloon on a balloon, says experimental physicist
9:23
Scott White to Katus at the University of Science and
9:27
Technology Austria in Kloustenburg. A big part of the problem
9:33
is that experiments tend to misbehave, with the same procedures
9:36
producing different results. Now researchers are picking apart some of
9:40
the puzzles that have long plagued the field with sophisticated
9:44
laboratory setups that carefully control for compounding factors. Way To
9:49
Katus and his team have found that the charging of
9:53
some materials has a strange tendency to hinge on their
9:57
past interactions a week in nature. Way To Catus and
10:02
his colleagues report that carbon carrying surface molecules can have
10:07
a role in guiding which way charge is exchanged. These
10:12
discoveries quote are the best work in early long time
10:15
in the field, says Daniel Lax, chemical engineer who has
10:20
studied triboelectricity at Case Western Reserve University in Cleveland. Other
10:26
teams are investigating how surface area and velocity during impact
10:31
might govern charge transfer, and how the breaking of chemical
10:35
bonds contributes. The influx of research seems to be driven
10:39
by a desire to scrutinize the fundamental physics at play,
10:43
says Lawrence Marx, a material scientists at Northwestern University in Evanston, Illinois.
10:49
A better understanding of the science of static electricity could
10:52
lead to improved devices that use it to power remote
10:57
sensors or wearable technologies without batteries, for example. It could
11:02
also help to prevent the electrical discharges that can cause
11:05
industrial explosions. It's becoming increasingly clear that static electricity is
11:11
far from a simple phenomenon that abides by one clear
11:14
cut set of rules. Instead, each exchange of charges could
11:18
be shaped by several factors that vary with the circumstances.
11:23
Some of these factors are now known, and others are
11:25
still waiting to be uncovered. The history of static electricity
11:30
dates back to at least the ancient Greek period. Triboelectric
11:34
includes the Greek words for rubbing and amber, because after
11:40
amber is rubbed against fur, it attracts light objects such
11:43
as feathers. At the end of the sixteenth century, English
11:46
physicist William Gilbert identified other materials that had the same
11:51
attractive power, including glass, diamond, and sapphires, and distinguish this
11:56
type of electrical pull from that of magnetism. In the
12:00
centuries it followed, scientists learned that lightning was an electrostatic discharge,
12:06
a supersized version of the benign zapp that comes from
12:09
shuffling feet across the carpet, and invented early electrostatic generators,
12:15
forerunners of the vandergraft generators that wow students in science museums.
12:21
By the mid eighteenth century, researchers had also begun documenting
12:25
which materials became negatively charged and which positively, producing lists
12:30
called triboelectric series. These rank materials from the most likely
12:36
to charge positively to the most likely to charge negatively,
12:40
with rabbit fur listed close to the top and silicon
12:45
near the bottom. There was a lull in efforts to
12:48
understand the phenomenon for part of the twentieth century, before
12:51
interest resurged around the turn of the twenty first century.
12:55
Marx attributes this renewed interest, at least in part to
12:58
the invention of the tribo electtionlectric nanogenerator. This device relies
13:04
on the triboelectric effect to convert mechanical energy into electricity.
13:10
It attracted researchers who were interested in fresh ways to
13:14
power small technologies. Quote In the last ten years, the
13:18
field has literally exploded, says Giulio Fatti, mechanical engineer at
13:23
Imperial College London. Even with the attention boost, however, the
13:27
fundamentals of triboelectricity have remained elusive. There are some generally
13:34
accepted ideas, says Marx. A material that has a specific
13:38
potential for a charged particle to escape that depends on
13:42
the material's surface and composition. This potential is called the
13:46
material's work function, and so far it applies best to
13:50
metallic materials. A sample also needs to be able to
13:54
trap the charge particles so they are kept in place
13:57
when the materials separate after the change, but physicists are
14:02
still pinning down the exact mechanisms behind these phenomena. Other
14:09
details of the contact seem to matter, too, But what
14:12
matters most under what matters most under which circumstances, and
14:17
for what materials remains unclear. Whether triboelectricity can be explained
14:24
by existing physics, or whether it demands its own model
14:28
has been an open question. Way to Katus and his team,
14:34
we're investigating how samples of the same material can exchange
14:37
a charge when they encountered. The inconsistent results that have
14:42
long frustrated researchers in the field, triboelectric series are difficult
14:47
to reproduce. Teams have obtained variable results concerning which materials
14:52
become more positively or negatively charged, and even different findings
14:57
with the same samples. Way to Katis, tasked his then
15:02
PhD student one, Carlos Sobarzo, with attempting to form a
15:07
series using samples of the same silicone based palmer. But
15:11
Sobarzo couldn't obtain any consistent results. In one experiment, sample
15:16
A would become negatively charged when interacting with sample B.
15:20
In the next, it would become positively charged. Quote. For
15:24
a very long time, we thought we were doing something wrong.
15:27
Way to Katas says, we thought there was some variable
15:30
we weren't controlling. But even when the team carefully controlled
15:35
for humidity, because researchers thought that water on a material
15:38
surface could affect how it charges, the results remained befuddling.
15:45
Then Sabarzo dug up a set of samples that had
15:47
already been through many experiments and tested how they interacted
15:51
with fresh ones. Quickly, the researchers noticed that the samples
15:55
that had been through more contact tended to become negatively charged.
15:59
In further, they kept track of how many contacts each
16:03
sample had already undergone. Quote That's when things started to
16:10
make sense. The samples that had more touches in their
16:13
history were always charging negatively. Way to Katus says, what
16:17
looked like chaos was an indication of the sample evolving.
16:22
The researchers suspect this evolution has to do with how
16:25
the sample's surface deforms with each contact. In the current paper,
16:32
way to Kati is working with Gallian, gross, gene and
16:36
applied physicists at the Autonomous University in Barcelona and their
16:41
colleagues looked deeper into how charges exchanged between two seemingly
16:45
identical materials. This time, they worked with oxides, materials such
16:50
as sand that are made up of atoms bonded oxygen,
16:53
and used several technologies, including a device that levitates samples
16:57
to keep their charge from changing. Also used a high
17:00
speed camera to measure the samples charge precisely. Before the experiment,
17:06
the scientists thought that water on the material's surface might
17:08
affect the charge exchange, but samples stored in either humid
17:13
or dry environment did not seem to be affected noticeably. Then,
17:17
the researchers bake the materials and found that the baked
17:20
samples tend to become charged negatively after contact and the
17:24
unbaked ones positively. After exploring the material's interfaces, the researchers
17:30
realized that the baking process change the results by getting
17:34
rid of the carbon carrying molecules on the material's surface.
17:38
These types of molecules, such as the carbon rich greenhouse
17:42
gas methane, are commonly picked up from the air. They
17:47
slowly but surely get on every surface. Gross Gene says
17:50
the finding suggest that the material is more likely to
17:53
become positively charged after contact if it has a greater
17:58
number of carbonation molecules on its surface. Waitakatis says the
18:04
team did a double take after discovering that it was
18:07
the carbon carrying molecules at play. Quote. You hardly ever
18:11
hear people talk about those molecules in the static electricity field.
18:15
He says these results provide first steps toward understanding which
18:20
factors influence charge transfer the most. So far, the contact
18:25
history finding seemed to pertain only to polymer materials such
18:29
as plastics, whereas the latest results applied just to oxides. Still,
18:35
the work indicates that there is no one size fits
18:38
all answer to how materials charge quote. The idea of
18:43
a permanent triboelectric ordering among different materials is a mirage,
18:48
says Way to catis that such small factors could be
18:52
so impactful isn't necessarily a new idea, says lax quote,
18:57
but what it totally what is totally new? Are these
19:00
really systematic experiments to prove that a particular contaminant is
19:04
playing a governing controlling role. He adds, the field has
19:09
quote moved away from the hand waving to a more
19:12
scientific proof. Other groups are doing their own disentangling. Researchers
19:18
in South Korea, for example, reported that they could control
19:21
the charge transfer by manipulating a material's internal electric field quote.
19:27
This is meaningful because triboelectricity had long been considered largely uncontrollable,
19:32
says study co author Sangwu Kim, who studies triboelectric energy
19:38
harvesting at Yonsei University in Seoul. The findings, Mark says,
19:43
fit with existing electromagnetic principles, suggesting that triboelectrification doesn't need
19:50
a fresh set of rules and a team in Germany
19:54
is found that as the impact velocity between two colliding
19:57
metals increases, so does the impact, which can affect charge transfer.
20:03
The link between impact velocity and charge transfer had been
20:07
up for debate. Fati and his collaborators have studied triboelectricity
20:13
and the breaking of chemical bonds, finding that a metal
20:16
can break the chemical bonds on a polymer's surface when
20:19
the two materials interact. This instability creates the right chemical
20:23
conditions for electrons to be exchanged to restabilize the bond.
20:29
The findings reported last January could help researchers to create
20:33
better performing triboelectric nanogenerators. Now that groups are beginning to
20:39
identify the parameters that matter most for some charge transfers,
20:44
Waiticatus hopes that physicists understanding of the phenomenon will be
20:49
rounded out. Quote. I'm not sure we're making things simpler,
20:52
he adds, but we're doing what is necessary to make
20:55
sense of this quote. And now an article from euro
21:00
News what is a super al Nino and will it
21:04
happen this year? This is from March thirty first. Global
21:09
temperatures could be pushed to unprecedented extremes, as climate pundits
21:14
worn a super El Nino is looking likely. Earlier this month,
21:19
the US National Oceanic and Atmospheric Administration revealed there is
21:24
a sixty two percent chance of Alnino forming this summer.
21:28
While model forecasts are relatively less accurate at this time
21:31
of the year, the increasing odds of al Nino occurring
21:34
later this year, are supported by large amounts of heat
21:38
in the subsurface ocean and the expected weakening of low
21:42
level trade winds. Quote If al Nino forms, the potential
21:46
strength remains very uncertain, with a one in three chance
21:50
that it would be strong during October to December. The
21:55
Noah Climate Prediction Center says La Nina, or Spanish for
22:00
the Girl, is the more common phenomenon that occurs when
22:05
trade winds in the Pacific tend to blow from east
22:07
to west, pushing warm surface waters towards the western Pacific.
22:12
This causes cold water to upwell or rise from the
22:15
depths of the ocean, making sea surface temperatures cooler, particularly
22:20
in the Americas. El Nino the Boy can be triggered
22:25
by a series of tropical wind bursts from the west
22:28
that weaken or even reverse these trade winds. When this occurs,
22:32
warm surface water sloshes back towards South America, where the
22:37
warming of surface water prevents the colder deep water from upwelling.
22:42
El Nino, which occurs irregularly and typically lasts for about
22:46
a year, tends to increase global temperatures, which in turn
22:50
can result in more extreme weather such as flooding. This
22:54
is because for every one degree rise that's one degree
22:57
celsius rise in temperature, the atmosphere can hold around seven
23:02
percent more moisture, leading to more intense and heavy rainfall.
23:07
Alninio can also intensify heat waves in the tropics, which
23:11
is why al nino years are often among the warmest
23:14
on record. The last al Nino occurred from May twenty
23:19
twenty three through March twenty twenty four, contributing towards record
23:22
breaking heat which fueled a series of deadly heat waves, wildfires,
23:27
and floods across the globe. Some meteorologists predict that a
23:31
typical al Nino event tends to cause a temporary point
23:36
one two point two percent celsius increase in not percent
23:42
that was degree celsius increase in the global mean temperature
23:47
point one too point two degrees. This is not as
23:50
significant as temperature rises fueled by human made climate change,
23:55
which has pushed the global surface temperature up by approximately
23:58
one point three to one point five degrees c. Multiple
24:04
newspapers and climate pundits have claimed this year's potential al
24:07
Nino will be a super version, but this isn't actually
24:12
an official scientific category. People may use the term super
24:17
informally to indicate al Nino's strength, which is usually defined
24:21
using the Oceanic Nino Index, but it isn't used by NOAH.
24:28
For al Nino conditions to form, monthly sea surface temperatures
24:31
in the central and eastern Tropical Pacific need to warmo
24:35
point five degrees c above normal, with the expectation that
24:40
the warming will persist for five consecutive overlapping three month periods.
24:47
Now we'll go back to Scientific American. This is dated
24:51
April first. The Alaskan permafrost is thawing. Here's why that's
24:56
so worrying. Thawing per is among climate science's worst positive
25:03
feedback loops. As the world warms, permafrost, essentially frozen soil, thaws,
25:11
releasing fresh water and carbon into the environment. That release
25:15
further fuels climate change, driving more warming. Thawing permafrost has
25:21
also raised concerns about unleashing new pathogens on humanity, and
25:29
in Alaska the loop seems to be speeding up. In
25:32
a new study, researchers tracked how thawing permafrost in a
25:36
wisconsinsized section of the North Slope region of Alaska has
25:41
added fresh water and dissolved organic carbon to estuaries off
25:45
the Alaskan coast between nineteen eighty and twenty twenty three.
25:50
In more recent years, the region released nearly twelve cubic
25:54
kilometers per year more water than it did from nineteen
25:58
eighty to nineteen eighty four. That's enough to fill more
26:02
than four and a half million Olympic swimming pools, estimates
26:05
Michael Rawlins, lead author of the study. Fresh water is
26:11
a problem for the ocean. It disrupts sea ice formation,
26:14
alters the salinity of coastal lagoons and bays, could threaten
26:18
global ocean circulation, and carries carbon that's later released into
26:23
the atmosphere. From the early nineteen eighties to twenty twenty three,
26:27
the amount of carbon that Northern Alaska's rivers release into
26:30
the ocean every year has risen from about one hundred
26:34
and twenty gigagrams to about one hundred and seventy gigagrams,
26:38
an increase of about fifty thousand metric tons of carbon
26:42
per year. Quote. Some of that carbon has been locked
26:45
up for tens of thousands of years. It's now thawed,
26:48
mobilized in the rivers, gets to the ocean where some
26:51
of it becomes part of the atmosphere, Rawlins says, comparing
26:55
this to fossil fuel extraction out gassing, the release of
27:00
methane or carbon dioxide can happen from rivers directly before
27:04
it reaches the ocean. The study could help researchers better
27:08
understand permafrost fueled carbon emissions across the Arctic, a region
27:12
that is warming about three times faster than the rest
27:15
of the planet. Quote. As we try to better understand
27:19
the amount of carbon in the ocean, we need good
27:22
estimates of the amount coming out of these rivers, Rollins says.
27:27
The findings were published in the journal Global Biogeochemical Cycles
27:36
and Now A quick Little story from BBC Wildlife. Platano Recto,
27:41
a land slightly smaller than the Isle of Wight, has
27:44
been off limits to visitors since being declared a turtle
27:46
sanctuary in nineteen sixty five. Little attention had been paid
27:51
to Platano's former banana plantations until American botanist April's Story
27:56
visited the island in twenty twenty five. She was astonished
28:00
to discover that every one of the island's rewilded banana
28:03
plants was producing arrow straight bananas. There wasn't a curve
28:08
in sight, said doctor Story, who went on to explain
28:11
why this is so rare. Bananas are naturally curved as
28:14
they grow upwards against gravity towards the Sun, but here
28:18
on platano they just grow straight down. Well that's all
28:22
for today's Diary of Science and Nature. I'm Kelly Taylor,
28:26
your reader. Now stay tuned for further programming on RADIOI