POST-SCARCITY ANARCHISM
BEFORE ECO SOCIALISM OR ECO MARXISM THERE WAS BOOKCHIN'S SOCIAL ECOLOGY
Wednesday, May 05, 2021
MARXISM AND ECOLOGICAL ECONOMICS
TOWARD A RED AND GREEN POLITICAL ECONOMY
PAUL BURKETT
HISTORICAL MATERIALISM #11
BOOK/PDF
https://www.academia.edu/32106183/_Paul_Burkett_Marxism_and_Ecological_Economics_T_BookZZ_org_
Cellphone converts into powerful chemical detector
With only $50 worth of components, an ordinary cellphone transforms into a sophisticated scientific instrument, capable of identifying chemicals, drugs, and pathogens
IMAGE: PHOTO SHOWING RELATIVE SIZE OF SPECTROMETER (LEFT) AND CELLPHONE (RIGHT AND AT THE LOWER END OF THE SPECTROMETER). view more
CREDIT: PETER RENTZEPIS
WASHINGTON, May 4, 2021 -- Scientists from Texas A&M have developed an extension to an ordinary cellphone that turns it into an instrument capable of detecting chemicals, drugs, biological molecules, and pathogens. The advance is reported in Reviews of Scientific Instruments, by AIP Publishing.
Modern cellphones include high-quality cameras capable of detecting low levels of light and eliminating digital noise through software processing of the captured images. Recent work has taken advantage of this sensitivity to produce cellphone cameras that can be used as portable microscopes and heart rate detectors.
The current advance is based on two types of spectroscopy. One type, known as fluorescence spectroscopy, measures the fluorescent light emitted by a sample. Another, known as Raman spectroscopy, is useful for detecting molecules, such as DNA and RNA, that do not fluoresce or emit light at very low intensities. Both types were used to develop this cellphone detector.
The system includes an inexpensive diode laser as a light source, oriented at right angles to the line connecting the sample and the cellphone camera. The right-angle arrangement prevents back reflected light from entering the camera.
"In addition, this right-angle excitation geometry has the advantage of being easier to use for the analysis of samples where a bulk property is to be measured," said author Peter Rentzepis.
The investigators studied a variety of samples using their constructed cellphone detector, including common solvents such as ethanol, acetone, isopropyl alcohol, and methanol. They recorded the Raman spectra of solid objects, including a carrot and a pellet of bacteria.
Carrots were chosen for this study because they contain the pigment carotene. The laser light used in their system has a wavelength that is easily absorbed by this orange pigment and by pigments in the bacteria.
The investigators compared the sensitivity of their system to the most sensitive industrial Raman spectrometers available. The ratio of signal to noise for the commercial instrument was about 10 times higher than the cellphone system.
The sensitivity of the cellphone detector could, however, be doubled by using a single RGB channel for analysis. The system has a rather limited dynamic range, but the investigators note that this problem can be easily overcome through several HDR, or High Dynamic Range, applications that combine images from multiple exposures.
The additional components, including the laser, add a cost of only about $50 to the price of a typical cellphone, making this system an inexpensive but accurate tool for detecting chemicals and pathogens in the field.
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The article "Cell-phone camera Raman spectrometer" is authored by Dinesh Dhankhar, Anushka Nagpal, and Peter M. Rentzepis. The article will appear in Review of Scientific Instruments on May 4, 2021 (DOI: 10.1063/5.0046281). After that date, it can be accessed at https:/
ABOUT THE JOURNAL
Review of Scientific Instruments publishes novel advancements in scientific instrumentation, apparatuses, techniques of experimental measurement, and related mathematical analysis. Its content includes publication on instruments covering all areas of science including physics, chemistry, materials science, and biology. See https:/
Study reveals the gateway to conscious awareness
Michigan Medicine researchers find out how some sensory information breaks through to conscious experience
During our waking hours, the brain is receiving a near-constant influx of sensory signals of various strengths. For decades, scientists have wondered why some signals rise to the light of conscious awareness while other signals of a similar strength remain in the dark shadows of unconsciousness. What controls the gate that separates the shadows and the light?
In a new study from the Department of Anesthesiology and Center for Consciousness Science at Michigan Medicine, researchers identify a key area in the cortex that appears to be the gate of conscious awareness.
"Information processing in the brain has two dimensions: sensory processing of the environment without awareness and the type that occurs when a stimulus reaches a certain level of importance and enters conscious awareness," explains Zirui Huang, Ph.D., research investigator in the Department of Anesthesiology.
Huang, along with lead researcher Anthony Hudetz, Ph.D. and their team, attempted to confirm that this switch occurs in a part of the brain called the anterior insular cortex, acting as a type of gate between low level sensory information and higher level awareness.
For the experiments, participants were put inside of a fMRI machine and administered the anesthetic drug propofol to control their level of consciousness. They were then asked to imagine themselves playing tennis, walking down a path or squeezing their hand, as well as asked to perform a motor activity (squeeze a rubber ball) as they gradually lost consciousness and regained it again after the propofol was stopped.
Previous research has shown that mental imagery produces brain activity similar to actually performing the activity. When participants imagine themselves playing tennis, the part of the brain responsible for controlling movement lights up. Other regions of the brain become deactivated when performing tasks, as mental attention is focused on the activity.
As the study participants began to lose consciousness, deactivations happened less frequently. When they completely lost consciousness, their corresponding brain areas also showed no activation in response to mental imagery tasks. As they regained some consciousness, they regained some activity related to mental imagery and with full consciousness shortly thereafter, their brain showed normal activation patterns.
Looking for the correlation across these states of consciousness revealed activation of the anterior insular cortex played a role in the successful switch between these activations and deactivations.
"A sensory stimulus will normally activate the anterior insular cortex," says Hudetz. "But when you lose consciousness, the anterior insular cortex is deactivated and network shifts in the brain that support consciousness are disrupted." The anterior insular cortex, he explains, might act as a filter that allows only the most important information to enter conscious awareness.
They sought to confirm their hypothesis with another classic psychological experiment, wherein a face is briefly flashed on a screen for a barely perceptible three hundredths of a second. The face image is followed by a noisy high contrast image designed to interrupt conscious processing of the face image. Participants were then asked whether they saw a face or not. Whether the face was consciously accessed was predicted by activation in the anterior insular cortex.
"Anterior insular cortex has continuously fluctuating activity," says Huang. "Whether you can detect a stimulus depends upon the state of the anterior insula when the information arrives in your brain: if the insula's activity is high at the point of stimulus, you will see the image. Based on evidence from these two experiments, we conclude that the anterior insular cortex could be a gate for conscious awareness."
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Paper cited: "Anterior insula regulates brain network transitions that gate conscious access," Cell Reports.
BLUE COLLAR LGBTQ
CN reviewing policy that withheld pension from gay widower
Duration: 02:10
CN Rail says it's reviewing its policy that kept a Newfoundland man from getting his deceased same-sex partner's company pension as a surviving spouse. CN rejected his claim for years, but a legal expert says the company would have little chance in court.
CBC.CA
Climate action potential in waste incineration plants
Over the coming decades, our economy and society will need to dramatically reduce greenhouse gas emissions as called for in the Paris Agreement. But even a future low-carbon economy will emit some greenhouse gases, such as in the manufacture of cement, steel, in livestock and crop farming, and in the chemical and pharmaceutical industries. To meet climate targets, these emissions need to be offset. Doing so requires "negative emissions" technologies, by means of which CO2 is removed from the atmosphere and permanently stored in underground repositories.
Researchers at ETH Zurich have now calculated the potential of one of these technologies for Europe: the combination of energy extraction from biomass with the capture and storage of CO2, or bioenergy with carbon capture and storage (BECCS) as it is known. The calculations revealed that if BECCS were exploited to its full potential, it would reduce carbon emissions in Europe by 200 million tonnes per year. This represents 5 percent of European emissions in 2018 and a substantial proportion of the 7.5 billion tonnes of CO2 that Europe has to cumulatively save by 2050 to reach its climate targets. As the authors of the study also point out, however, fully exploiting the calculated potential of BECCS will be challenging in practice.
Technology ready for action
BECCS involves capturing CO2 at the point sources where it is produced from biological material. In Europe, companies in the pulp and paper industry offer the greatest potential. Other sectors with potential are waste incineration plants (where around half the waste is from biomass), combined heat and power plants that run on wood, and biogas plants that use compostable municipal waste or plant and animal byproducts of food production that are not suitable for eating. Further sources are wastewater treatment plants and livestock manure.
"The technology for capturing carbon dioxide at such point sources is ready to go," explains Marco Mazzotti, Professor at the Institute of Energy and Process Engineering and head of the study. The carbon would then have to be transported to storage locations via a network yet to be created - in pipelines, for instance. "This is a major challenge," says Lorenzo Rosa, scientist in Mazzotti's group and lead author of the study. After all, CO2 is produced unevenly across Europe. Suitable storage sites are now present only in a few places, far from the CO2 point sources, such as underneath the seabed of the North Sea. However, this challenge is solvable if such a transport network were to be built up as quickly as possible, says Rosa.
Paper industry
As the calculations of the ETH researchers revealed, the potential of BECCS varies greatly from country to country. At one extreme is Sweden, which has a strong pulp and paper industry. By using BECCS, Sweden could capture almost three times as much carbon dioxide from biomass (and thus atmospheric origin) as it emits from fossil fuels today. "If Sweden were to exploit its full BECCS potential, it could trade emission certificates and thus offset emissions in other countries," says Rosa. Finland and Estonia could reduce their CO2 emissions by half, also possible thanks to a strong pulp and paper industry. In many other European countries, the potential is lower, with emissions reductions of around 5 percent or less.
For their calculations, the ETH scientists took into account only biomass that arises as a byproduct of industry or agriculture or as waste. They deliberately factored out crops grown for the primary purpose of energy production, a practice that is more widespread in other regions of the world than in Europe. Because such farming is in direct competition with food crops, it is not considered very sustainable. "With global food demand expected to double by 2050, there is a pressing need to develop BECCS technologies that do not rely on purpose-grown bio-energy plantations," says Rosa.
Waste as raw material
In Switzerland, the BECCS potential is about 6 percent. Waste incineration plants could make up a large portion of this total. "In many other regions of Europe, by contrast, this potential lies idle, as waste is dumped unused in landfills," says ETH Professor Mazzotti.
Waste incineration plants already fulfil three important functions today: they dispose of waste; they recycle raw materials, as far as possible; and they generate district heating and electricity. "Now a fourth function is being added: as significant negative emissions facilities, waste incineration plants can help reduce the carbon footprint of our society," says Mazzotti. At present, this potential is going untapped. For the most part, no carbon dioxide is being captured yet in paper, incineration or biogas plants. In the opinion of the ETH researchers, we should start doing so as soon as possible.
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Citrus derivative makes transparent wood 100 percent renewable
T: CÉLINE MONTANARI
Since it was first introduced in 2016, transparent wood has been developed by researchers at KTH Royal Institute of Technology as an innovative structural material for building construction. It lets natural light through and can even store thermal energy.
The key to making wood into a transparent composite material is to strip out its lignin, the major light-absorbing component in wood. But the empty pores left behind by the absence of lignin need to be filled with something that restores the wood's strength and allows light to permeate.
In earlier versions of the composite, researchers at KTH's Wallenberg Wood Science Centre used fossil-based polymers. Now, the researchers have successfully tested an eco-friendly alternative: limonene acrylate, a monomer made from limonene. They reported their results in Advanced Science.
"The new limonene acrylate it is made from renewable citrus, such as peel waste that can be recycled from the orange juice industry," says lead author, PhD student Céline Montanari.
An extract from orange juice production is used to create the polymer that restores delignified wood's strength and allows light to pass through.
The new composite offers optical transmittance of 90 percent at 1.2 mm thickness and remarkably low haze of 30 percent, the researchers report. Unlike other transparent wood composites developed during the past five years, the material developed at KTH is intended for structural use. It shows heavy-duty mechanical performance: with a strength of 174 MPa (25.2 ksi) and elasticity of 17 GPa (or about 2.5 Mpsi).
Yet all along, sustainability has been a priority for the research group, says Professor Lars Berglund, the head of the KTH's Department of Fibre and Polymer Technology.
"Replacing the fossil-based polymers has been one of the challenges we have had in making sustainable transparent wood," Berglund says.
Environmental considerations and so-called green chemistry permeate the entire work, he says. The material is made with no solvents, and all chemicals are derived from bio-based raw materials.
The new advances could enable a yet unexplored range of applications, such as in wood nanotechnology, Berglund says. Possibilities include smart windows, wood for heat-storage, wood that has built-in lighting function - even a wooden laser.
"We have looked at where the light goes, and what happens when it hits the cellulose," Berglund says. "Some of the light goes straight through the wood, and makes the material transparent. Some of the light is refracted and scattered at different angles and gives pleasant effects in lighting applications."
The team is also working with Sergei Popov's photonics group at KTH to explore the nanotechnology possibilities even further.
CAPTION
Previous versions of the see-through wood developed at KTH, left, are seen together with the latest, more translucent type developed with citrus derivatives.
CREDIT
Céline Montanari
Surfaces can be designed with antiviral properties to mitigate COVID-19
An optimally designed surface can speed the decay of a viral load
IMAGE: SURFACES WITH TALLER AND CLOSELY PACKED PILLARS WITH A CONTACT ANGLE OF AROUND 60 DEGREES SHOW THE STRONGEST ANTIVIRAL EFFECT OR SHORTEST DRYING TIME. view more
CREDIT: S. CHATTERJEE, J.S. MURALLIDHARAN, A. AGRAWAL, AND R. BHARDWAJ
WASHINGTON, May 4, 2021 -- If a respiratory droplet from a person infected with COVID-19 lands on a surface, it becomes a possible source of disease spread. This is known as the fomite route of disease spread, in which the aqueous phase of the respiratory droplet serves as a medium for virus survival.
The lifespan of the respiratory droplet dictates how likely a surface is to spread a virus. While 99.9% of the droplet's liquid content evaporates within a few minutes, a residual thin film that allows the virus to survive can be left behind.
This begs the question: Is it possible to design surfaces to reduce the survival time of viruses, including the coronavirus that causes COVID-19? In Physics of Fluids, from AIP Publishing, IIT Bombay researchers present their work exploring how the evaporation rate of residual thin films can be accelerated by tuning surfaces' wettability and creating geometric microtextures on them.
An optimally designed surface will make a viral load decay rapidly, rendering it less likely to contribute to the spread of viruses.
"In terms of physics, the solid-liquid interfacial energy is enhanced by a combination of our proposed surface engineering and augmenting the disjoining pressure within the residual thin film, which will speed drying of the thin film," said Sanghamitro Chatterjee, lead author and a postdoctoral fellow in the mechanical engineering department.
The researchers were surprised to discover that the combination of a surface's wettability and its physical texture determine its antiviral properties.
"Continuously tailoring any one of these parameters wouldn't achieve the best results," said Amit Agrawal, a co-author. "The most conductive antiviral effect lies within an optimized range of both wettability and texture."
While previous studies reported antibacterial effects by designing superhydrophobic (repels water) surfaces, their work indicates antiviral surface design can be achieved by surface hydrophilicity (attracts water).
"Our present work demonstrates that designing anti-COVID-19 surfaces is possible," said Janini Murallidharan, a co-author. "We also propose a design methodology and provide parameters needed to engineer surfaces with the shortest virus survival times."
The researchers discovered that surfaces with taller and closely packed pillars, with a contact angle of around 60 degrees, show the strongest antiviral effect or shortest drying time.
This work paves the way for fabricating antiviral surfaces that will be useful in designing hospital equipment, medical or pathology equipment, as well as frequently touched surfaces, like door handles, smartphone screens, or surfaces within areas prone to outbreaks.
"In the future, our model can readily be extended to respiratory diseases like influenza A, which spread through fomite transmission," said Rajneesh Bhardwaj, a co-author. "Since we analyzed antiviral effects by a generic model independent of the specific geometry of texture, it's possible to fabricate any geometric structures based on different fabrication techniques -- focused ion beams or chemical etching -- to achieve the same outcome."
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The article "Designing antiviral surfaces to suppress the spread of COVID-19" is authored by Sanghamitro Chatterjee, Janani Srree Murallidharan, Amit Agrawal, and Rajneesh Bhardwaj. It will appear in Physics of Fluids on May 4, 2021 (DOI: 10.1063/5.0049404). After that date, it can be accessed at https:/
ABOUT THE JOURNAL
Physics of Fluids is devoted to the publication of original theoretical, computational, and experimental contributions to the dynamics of gases, liquids, and complex fluids. See https:/
How the Full Moon briefly vanished, nearly a thousand years ago
Scott Sutherland
According to records over nine hundred years old, witnesses reported that the Full Moon briefly vanished from the sky during a total lunar eclipse.
Scott Sutherland
According to records over nine hundred years old, witnesses reported that the Full Moon briefly vanished from the sky during a total lunar eclipse.
Provided by The Weather Network
This image of the Super Blood Wolf Moon total lunar eclipse was shot on January 20, 2019, from Richmond, BC, before the Moon was completely enveloped in Earth's shadow. Credit: Tony Venezuela/UGC
According to the Peterborough Chronicle, which catalogued noteable events throughout out England's history, in the year 1110: "On the fifth night of the month of May the moon appeared shining brightly in the evening, and afterwards his light waned by little and little, and early in the night he was so wholly gone that neither light, nor circle, nor anything at all of him was to be seen, and thus it continued till near day, and then he appeared shining full and bright; he was a fortnight old the same day: the sky was very clear all the night, and the stars shone very brightly all over the heavens, and the fruit trees were greatly injured by that night's frost."
How did this vanishing act occur, though?
During a total lunar eclipse, the Moon passes directly through Earth's shadow. First, it simply grows dinner, then it appears as though a great disk of darkness slowly advances across its face until it is completely immersed in the darkest part of the shadow, the umbra. That is when we see it shine with the familiar dusky red colour we've come to expect during one of these events.
According to the Peterborough Chronicle, which catalogued noteable events throughout out England's history, in the year 1110: "On the fifth night of the month of May the moon appeared shining brightly in the evening, and afterwards his light waned by little and little, and early in the night he was so wholly gone that neither light, nor circle, nor anything at all of him was to be seen, and thus it continued till near day, and then he appeared shining full and bright; he was a fortnight old the same day: the sky was very clear all the night, and the stars shone very brightly all over the heavens, and the fruit trees were greatly injured by that night's frost."
How did this vanishing act occur, though?
During a total lunar eclipse, the Moon passes directly through Earth's shadow. First, it simply grows dinner, then it appears as though a great disk of darkness slowly advances across its face until it is completely immersed in the darkest part of the shadow, the umbra. That is when we see it shine with the familiar dusky red colour we've come to expect during one of these events.
© Provided by The Weather NetworkThis exaggerated diagram shows how Earth's shadow is split into two parts, the dark red umbra and the more diffuse penumbra. Credit: NASA
At no time does the Moon appear to vanish, though. So, what happened during the May 5, 1110 eclipse to cause the Moon to disappear from sight?
The red colouration we see during a total lunar eclipse is from sunlight filtering through the planet's atmosphere. Essentially, it is the red tinge of every sunrise and sunset happening on Earth at the time, shining into the umbra and onto the Moon, all at once.
At no time does the Moon appear to vanish, though. So, what happened during the May 5, 1110 eclipse to cause the Moon to disappear from sight?
The red colouration we see during a total lunar eclipse is from sunlight filtering through the planet's atmosphere. Essentially, it is the red tinge of every sunrise and sunset happening on Earth at the time, shining into the umbra and onto the Moon, all at once.
© Provided by The Weather Network
This simulated view shows what an astronaut on the Moon would see during a total lunar eclipse — all of Earth's sunrises and sunsets, all at once. Credit: NASA
What happens, though, if Earth's atmosphere doesn't allow any light to escape and shine into the umbra?
This appears to be what happened in 1110. As reported in a study published in 2020, scientists found that a series of eruptions of Japan's Mount Asama, starting two years before in August to October of 1108, may have been responsible.
During powerful volcanic eruptions, ash and other fine particles are blasted up into the stratosphere, high above the ground, where they can linger for years. The extra scattering of light produced by these particles can treat us to some vivid red sunsets. At the same time, though, they can completely scatter the visible light before it can escape back into space and shine into the umbra. Thus, a uniform blackness would replace the umbra's typical hue, and an eclipsed Moon could appear to vanish from the sky.
What happens, though, if Earth's atmosphere doesn't allow any light to escape and shine into the umbra?
This appears to be what happened in 1110. As reported in a study published in 2020, scientists found that a series of eruptions of Japan's Mount Asama, starting two years before in August to October of 1108, may have been responsible.
During powerful volcanic eruptions, ash and other fine particles are blasted up into the stratosphere, high above the ground, where they can linger for years. The extra scattering of light produced by these particles can treat us to some vivid red sunsets. At the same time, though, they can completely scatter the visible light before it can escape back into space and shine into the umbra. Thus, a uniform blackness would replace the umbra's typical hue, and an eclipsed Moon could appear to vanish from the sky.
© Provided by The Weather Network
Although such a 'dark' lunar eclipse is extremely rare, it is possible that one could happen again. It only requires a sufficiently powerful volcanic eruption and an appropriately timed eclipse.
The next total lunar eclipse is the Super Blood Flower Moon, which will be visible across parts of Canada on the morning of May 26, 2021, with western regions of the country getting the best view.
This Day In Weather History is a daily podcast by The Weather Network that features unique and informative stories from host Chris Mei.
Although such a 'dark' lunar eclipse is extremely rare, it is possible that one could happen again. It only requires a sufficiently powerful volcanic eruption and an appropriately timed eclipse.
The next total lunar eclipse is the Super Blood Flower Moon, which will be visible across parts of Canada on the morning of May 26, 2021, with western regions of the country getting the best view.
This Day In Weather History is a daily podcast by The Weather Network that features unique and informative stories from host Chris Mei.
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