SOUTHWEST RETORT
SEVENTY-FOURTH YEAR
May 2022
Published for the advancement of Chemists, Chemical Engineers and Chemistry in this area published by The Dallas-Fort Worth Section, with the cooperation of five other local sections of the American Chemical Society in the Southwest Region.
Vol. 74(9) May 2022 Editorial and Business Offices: Contact the Editor for subscription and advertisement information. Editor: Connie Hendrickson: retort@acsdfw.org Copy and Layout Editor: Lance Hughes: hugla64@gmail.com Business Manager: Martha Gilchrist: Martha.Gilchrist@tccd.edu The Southwest Retort is published monthly, September through May, by the Dallas-Ft. Worth Section of the American Chemical Society, Inc., for the ACS Sections of the Southwest Region.
May 2022
The Southwest RETORT
1
TABLE OF CONTENTS Fifty Years Ago………………………….......5 ARTICLES and COLUMNS Letter from the Editor…..…..……..............17
NEWS SHORTS New Cocoa Processing Method Produces Fruitier, More ‘Flowery’ Dark Chocolate....6 A ‘Greener’ Alternative for Red-Colored Smoke……………………………….……….8 A New Wearable Technology — for Plants (video)..…………………………………......10 Edible, Fluorescent Silk Tags can Suss Out Fake Medications ..………………………. .11 Earthworms like to Eat Some Plastics, but Side Effects of Their Digestion are Unclear…………………………………..……..12 Weed-killer Compounds also Kill Parasite sometimes found in Cat Feces…...………...13 D Printing Smart Clothes with a new Liquid Metal-Alginate Ink (video) …………..…...14 AROUND THE AREA
UT Arlington………...……………...….…..16 UT Dallas……………………...……………16 ANNOUNCMENTS
Contact the DFW Section General: info@acsdfw.org Education: ncw@acsdfw.org Elections: candidates@acsdfw.org Facebook: DFWACS Twitter: acsdfw
May 2022
INDEX OF ADVERTISERS Huffman Laboratories……………..…........3 TMJ Data Entry and Editing.………......…3 ANA-LAB…………………………...….…..4
The Southwest RETORT
2
SERVICES and ANNOUNCEMENTS
TMJ Data Entry and Editing Specializes in: •
Company newsletters
•
Confidential Data Entry
•
Free Quotes
Contact Lance at hugla64@gmail.com
Your Ad Here Could Reach Other ACS Members
Or 214-356-9002
May 2022
The Southwest RETORT
3
DOCUMENT TITLE
May 2022
The Southwest RETORT
4
Fifty Years Ago in the Southwest Retort Heads up to our readers! Dallas will host the ACS Spring National Meeting next year on April 8-13, 1973. The ACS Southwest Regional Meeting will be held Dec. 6-8 this year in Baton Rouge. The Arthur H. Thomas Co. announces the Automatic Printout Titrator, Thomas Model 55. At Northeast Louisiana University, Department Chair Dr. Earl W. Baker has received a $2000 grant to study organic geochemistry. Texas A&M’s Chemistry Department has received a $57,000 NSF grant matched by departmental funds to purchase a multinuclear nuclear magnetic resonance spectrometer. The 11th National Meeting of the SociCompiled by ety for Applied E. Thomas Strom Spectroscopy will be hosted by the North Texas Section of the Society and by the Dallas Society of Analytical Chemists. The meeting will be held in Dallas Sept. 10-15 at the Statler Hilton Hotel. The Fifth Annual DFW Section Meeting-inMiniature was held April 28 at Texas Woman’s University. There were twenty-one graduate presentations and eighteen undergraduate presentations. Winners were as follows: Graduate; 1st, John D. Scott, North Texas State; 2nd, J. M. Hopkins, East
May 2022
Texas State; 3rd, H. J. Barager, TCU; Undergraduate, 1st, Yvonne Kunz, Texas Woman’s University; 2nd, Doug Winters, Abilene Christian; 3rd. S. Walter, North Texas State. The banquet speaker was ACS District 4 Director Dr. Mary L. Good speaking on “Chemists—Supply and Demand. At SMU Dr. Edward Biehl and Dr. Perry Reeves are in charge of the new PerkinElmer Model R12B NMR Spectrometer received in April. Dr. Harold Jeskey, President of the Southwestern Athletic Conference, presided at the April meeting held in Fayetteville, AR. Dr. Ralph Shriner attended the Board of Directors meeting of Organic Synthesis, Inc. held at the recent ACS meeting in Boston. The North Texas State chemistry department will host the National Organosilicon Symposium April 6-7, 1973. Dr. Paul R. Jones of NTSU will chair the symposium. Dr. Robert W. Gracy has received a five year Career Development Award from NIH to study “Erythrocyte Metabolism.” Drs. James L. Marshall, Robert Disiderato, and Robert W. Gracy have received Welch grants. The NTSU Biochemistry Division will be participating in the Texas College of Osteopathic Medicine Program this fall At the UT-Southwestern Medical School, Dr. Ronald Estabrook lectured at the University of Mexico on “Biological Oxidation and Reduction.” Dr. Morton Prager has received NIH and Welch grants to study “Tumor Inhibitory Enzymes.” At UT-Austin, Dr. Allen Bard was an ACS tour speaker in Ohio.
The Southwest RETORT
5
From the ACS Press Room New Cocoa Processing Method Produces Fruitier, More ‘Flowery’ Dark Chocolate “Comparison of the Aroma Composition and Sensory Properties of Dark Chocolates Made with Moist Incubated and Fermented Cocoa Beans” Journal of Agricultural and Food Chemistry Producing chocolate, one of the world’s most beloved sweets, is a multistep process beginning with freshly harvested cocoa beans. People have been experimenting with chocolate-making for millennia, and even today, new methods are still being introduced. Now, researchers reporting in ACS’ Journal of Agricultural and Food Chemistry have found that an alternative processing step called “moist incubation” results in a fruitier, more flowery-tasting dark chocolate than the conventional fermentation process.
After cocoa beans are harvested, they are traditionally covered in banana leaves and left for a few days to ferment. During this time, microbes in the environment degrade the pulp surrounding the beans, heating and acidifying them. This causes biochemical changes in the beans that reduce bitterness and astringency, while developing the pleasing flavors and aromas associated with chocolate. Recently, scientists developed an alternative, non-microbial approach called moist incubation, in which dried, unfermented cocoa nibs are rehydrated in an acidic solution, heated for 72 hours and then re-dried. The method, which is faster and more easily conMay 2022
trolled than fermentation, produced similar aromas in beans as fermentation, with some differences. Irene Chetschik, Ansgar Schlüter and colleagues wanted to find out how the taste and aroma of the final product — chocolate — compared when using moist incubation versus traditional fermentation. The researchers made chocolate bars using
moist incubated or fermented dried cocoa beans, as well as unfermented beans as a control. Sensory panelists said the moist incubated sample had higher intensities of fruity, flowery, malty and caramel-like aromas, whereas the fermented one had higher roasty aroma notes, and the bar made from unfermented beans had a primarily green aroma. The panelists rated the moist incubated sample as the sweetest-tasting, while the unfermented chocolate was the most bitter and astringent. Identification of aroma compounds by gas chromatography (GC)-
The Southwest RETORT
6
olfactometry and their subsequent quantitation by GC-mass spectrometry revealed higher levels of malty compounds called Strecker aldehydes and lower amounts of roasty compounds called pyrazines in the moist incubated chocolate compared with the fermented one. The researchers concluded that moist incubation produces a chocolate with a pleasant aroma and taste and could, therefore, serve as an alternative postharvest treatment.
The authors acknowledge funding from Zurich University of Applied Sciences (ZHAW).
2022 DFW Section Officers Chair: Mihaela C. Stefan Chair-elect: Rajani Srinivasan Past Chair: Trey Putnam Treasurer: Martha Gilchrist
Secretary: Violeta Vega Gomez Councilors: Mary Anderson Kirby Drake Linda SchultzR Rebecca Weber Alternate Councilors:
Michael Bigwood Daniela Hutanu Danny Tran
May 2022
The Southwest RETORT
7
From the ACS Press Room
A ‘Greener’ Alternative for Red-Colored Smoke “Diketopyrrolopyrrole — A Greener Alter- “Ferrari red”), optics technologies and other native for Pyrotechnic Smoke Composi- applications. For the purpose of signal tions” smokes, Vojtech Pelikan and colleagues chose the DPP dye PR254, which has a brilACS Sustainable Chemistry & Engineering liant red color and is less toxic than anthraThe red smoke of a flare on a roadway warns quinone dyes. In experiments, the researchers motorists to be cautious, but the anthraqui- showed that a PR254-containing pyrotechnic none dyes currently used to produce this composition reached a yield of red-colored smoke are thought to be harmful to human smoke of 51%, compared with only 48% for
health. Now, researchers reporting in ACS Sustainable Chemistry & Engineering have identified a less toxic, “greener” alternative — an organic dye called pigment red 254 (PR254). It also forms a red-colored smoke cloud more effectively than current dyes, the researchers say. Commercialized in 1986, diketopyrrolopyrrole (DPP) dyes are used as colorants in car paints (such as the famous May 2022
the usual anthraquinone dye. PR254 was also more thermally stable than the reference dye, which might allow it to be used in a less toxic heat-generating system, according to the researchers. The authors acknowledge funding from the University of Pardubice.
The Southwest RETORT
8
May 2022
The Southwest RETORT
9
From the ACS Press Room A New Wearable Technology — for Plants (video) “Biocompatible Wearable Electrodes on Leaves toward the On-Site Monitoring of Water Loss from Plants”
ACS Applied Materials & Interfaces Plants can’t speak up when they are thirsty. And visual signs, such as shriveling or browning leaves, don’t start until most of their water is gone. To detect water loss earlier, researchers reporting in ACS Applied Materials & Interfaces have created a wearable sensor for plant leaves. The system wirelessly transmits data to a smartphone app, allowing for remote management of drought stress in gardens and crops. Watch a video of the plant wearables here. Youtube ID: i864_c0fvVg
Newer wearable devices are more than simple step-counters. Some smart watches now monitor the electrical activity of the wearer’s heart with electrodes that sit against the skin. And because many devices can wirelessly share the data that are collected, physicians can monitor and assess their patients’ health from a distance. Similarly, plant-wearable devices could help farmers and gardeners remotely monitor their plants’ health, including leaf water content — the key marker of metabolism and drought stress. Previously, researchers had developed metal electrodes for this purpose, but the electrodes had problems staying attached, which reduced the accuracy of the data. So, Renato Lima and colleagues wanted to identify an electrode design that was reliable for long-term monitoring of plants’ water stress, while also staying put.
May 2022
The researchers created two types of electrodes: one made of nickel deposited in a narrow, squiggly pattern, and the other cut from partially burnt paper that was coated with a waxy film. When the team affixed both electrodes to detached soybean leaves with clear adhesive tape, the nickel-based electrodes performed better, producing larger signals as the leaves dried out. The metal ones also adhered more strongly in the wind, which was likely because the thin squiggly design of the metallic film allowed more of the tape to connect with the leaf surface. Next, the researchers created a plant-wearable device with the metal electrodes and attached it to a living plant in a greenhouse. The device wirelessly shared data to a smartphone app and website, and a simple, fast machine learning technique successfully converted these data to the percent of water content lost. The researchers say that monitoring water content on leaves can indirectly provide information on exposure to pests and toxic agents. Because the plant-wearable device provides reliable data indoors, they now plan to test the devices in outdoor gardens and crops to determine when plants need to be watered, potentially saving resources and increasing yields. The authors acknowledge support from the São Paulo Research Foundation and the Brazilian Synchrotron Light Laboratory. Two of the study’s authors are listed on a patent filing application for the technology.
The Southwest RETORT
10
From the ACS Press Room
Edible, Fluorescent Silk Tags can Suss Out Fake Medications “Edible Matrix Code with Photogenic Silk Proteins” ACS Central Science
as tracking codes, but the substances are potentially unsafe to consume. So, Seong-Wan Kim, Young Kim and colleagues wanted to see whether silk, which is an edible and “generally recognized as safe” material, could be placed directly onto medications and made to fluoresce, helping consumers make sure their purchases are what they claim to be.
Recent developments such as the explosion of online pharmacies and supply chain issues have made it easier for counterfeiters to profit from fake or adulterated medications. Now, researchers reporting in ACS Central The researchers genetically modified silkScience have created edible tags with fluo- worms to produce silk fibroins — edible prorescent silk proteins, which could be placed directly on pills or in a liquid medicine. The codes within the tags can be read by a smartphone app to verify the source and quality of these pharmaceuticals. Online pharmacies have taken off in recent years, delivering many types of medications directly to consumers’ homes. Some of these businesses are legitimate, but others operate illegally, supplying counterfeit drugs that are substandard, incorrectly labeled or laced with unwanted components. In addition, global supply chain problems have made it easy for fake medications to infiltrate the market. To instill trust in consumers, pharma companies label the outside packaging of their products with bar codes, QR codes, holograms and radio frequency identifiers, allowing distributors and retailers to manage products throughout the supply chain. Yet there aren’t equivalent codes for consumers to verify the source of individual pills or liquid doses inside a container. Researchers have developed fluorescent synthetic materials, such as microfibers and nanoparticles, May 2022
teins that gives silk fibers their strength — with either a cyan, green or red fluorescent protein attached. They dissolved the fluorescent silk cocoons to create fluorescent polymer solutions, which they applied onto a thin, 9-mm-wide film of white silk in a seven-byseven grid. Shining blue violet, blue, and green light onto the grid revealed the 3D cyan, green and red square patterns, respectively. Using optical filters over the phone’s camera, an app the team designed can scan the fluorescent pattern, decoding the digitized key using a deep learning algorithm and opening up a webpage, which could host information about the drug’s source and authenticity. And Continued on page 15
The Southwest RETORT
11
From the ACS Press Room Earthworms like to Eat Some Plastics, but Side Effects of Their Digestion are Unclear “Earthworms’ Degradable Bioplastic Diet of Polylactic Acid: Easy to Break and Slow to Excrete”
that earthworms will ingest these synthetic particles, even breaking them apart into smaller pieces. But during the digestion process, animals could potentially be harmed by Environmental Science & Technology the microplastics themselves or by the toxic .Earthworms are a welcome sight for garden- substances they carry. Currently, companies ers and farmers because the wriggling inver- are producing alternatives to petroleumtebrates recycle nutrients from soil, making based plastics that are derived from plants, them more accessible to plants. As worms are biodegradable or both. Just like traditionburrow, they consume almost everything in al plastics, these “bioplastics” can also fragtheir path, including microscopic plastic pol- ment into microscopic particles, but there is lution. Now, researchers reporting in limited information on whether earthworms ACS’ Environmental Science & Technolo- will also ingest and decompose these materigy have observed that earthworms actually als. So, Lei Wang and colleagues wanted to prefer soil with some types of microplastics compare the willingness of earthworms to but digest the polymers differently, which the consume soil laced with microscopic pieces team suggests could impact the animals’ of bioplastic and petroleum-derived plastic, health and the ecosystem. studying the in vitro digestion and excretion of the particles. By placing earthworms in chambers with different types of plastics in certain locations in the soil, the researchers found that worms preferred soils with bio-based polylactic acid (PLA) particles or petroleum-derived polyethylene terephthalate (PET) particles but actively avoided some semi-synthetic plastics. When lactic acid and terephthalic acid, soursmelling monomers that make up PLA and PET, respectively, were spiked into soil, the worms were also attracted, suggesting that Soil is becoming increasingly contaminated the animals were drawn in by the odors as by fragments of plastic – especially micro- potential cues for food. In another experiplastics less than 5 mm wide – that have bro- ment, the researchers put earthworms in soil ken off of larger plastic waste or have been directly released from products as small particles. Previously, researchers have shown Continued on page 15 May 2022
The Southwest RETORT
12
From the ACS Press Room
Weed-killer Compounds also Kill Parasite sometimes found in Cat Feces pound called heme, is the target of some common herbicides, including oxadiazon. Kerrick Rees, Zhicheng Dou and Daniel Whitehead wondered if these herbicides or their derivatives could kill not only weeds, ACS Infectious Diseases but also T. gondii — without harming human The parasite Toxoplasma gondii infects up to cells. one-third of the human population, experts The researchers screened several herbicides say. Sometimes transmitted to humans from for the ability to kill T. gondii that had infectinfected cat feces or litter, the protozoan can ed human cells in a dish, finding that oxadiacause severe and even deadly illnesses in imzon and a related compound, oxadiargyl, munocompromised people and fetuses. Now, were the most effective. Then, they syntheresearchers reporting in ACS Infectious Dissized 18 derivaeases have discovered that common herbitives of cides and some of their derivatives can kill oxadiargyl that the parasite when it infects human cells in a had different petri dish, without harming the cells themchemical selves. groups at a cerT. gondii infection usually occurs from eating tain region of undercooked contaminated meat, exposure to the molecule, infected cat feces or mother-to-child trans- identifying mission during pregnancy. The parasite caus- some that were es mild or no symptoms in most people, but it even more pocan cause severe illnesses in immunocompro- tent than the mised people and birth defects in the fetuses parent compound. In other experiments, the of pregnant women. Current therapies have researchers confirmed that the herbicide delimitations, such as strong side effects and an rivatives work primarily by inhibiting PPO. inability to cross the placenta to treat the fe- Importantly, the compounds didn’t harm hutus. They also don’t work well for chronic man cells that hosted the parasites. Next, the infections. Recently, scientists discovered researchers plan to test the most potent molethat T. gondii expresses an enzyme cules in an animal model of T. (protoporphyrinogen oxidase, or PPO) that gondii infection. more closely resembles the plant version of The authors acknowledge funding from the the enzyme than the mammalian one. Plant National Institutes of Health. PPO, which helps make an essential com“Oxadiazon Derivatives Elicit Potent Intracellular Growth Inhibition against Toxoplasma gondii by Disrupting Heme Biosynthesis”
May 2022
The Southwest RETORT
13
From the ACS Press Room D Printing Smart Clothes with a new Liquid Metal-Alginate Ink (video) “Liquid Metal Microgels for ThreeDimensional Printing of Smart Electronic Clothes”
shell. The ink was very thick until it was squeezed through a nozzle for 3D printing, which broke hydrogen bonds in the microgel and made it more fluid. Once the ink reached ACS Applied Materials & Interfaces the fabric surface, the hydrogen bonds reIn the future, smart clothing might monitor formed, causing the printed pattern to mainour posture, communicate with smartphones tain its shape. The team 3D printed the new and manage our body temperature. But first, scientists need to find a way to cost- ink onto a variety of surfaces, including paeffectively print intricate, flexible and dura- per, polyester fabrics, nonwoven fabrics and ble circuits onto a variety of fabrics. Now, acrylic-based tape. Although the printed patresearchers reporting in ACS Applied Materi- terns were not initially conductive, the reals & Interfaces have developed a conduc- searchers activated them by stretching, presstive 3D printing ink made of liquid metal ing or freezing, which ruptured the dried aldroplets coated with alginate, a polymer de- ginate networks to connect the LM microrived from algae. Watch a video about the droplets. new ink here. Youtube ID: hyEGK8NmCiI Conventional electronics are rigid and unable to withstand the twisting and stretching motions that clothing undergoes during typical daily activities. Because of their fluid nature and excellent conductivity, gallium-based liquid metals (LMs) are promising materials for flexible electronics. However, LMs don’t stick well to fabrics, and their large surface tension causes them to ball up during 3D printing, rather than form continuous circuits. Yong He and colleagues wanted to develop a new type of conductive ink that could be 3D printed directly onto clothing in complex patterns. To make their ink, the researchers mixed LM and alginate. Stirring the solution and removing the excess liquid resulted in LM microdroplets coated with an alginate microgel May 2022
After activation, the printed circuits had excellent electrical conductivity and strain sensing properties. In addition, applying a small voltage to the ends of the circuit caused it to heat up, even in very cold temperatures. To demonstrate the ink’s capabilities, the team 3D printed a series of electronics onto commercial clothing. On a T-shirt, they printed a near-field communication tag that directed a smartphone placed nearby to open a web site. Other sensors printed on clothing monitored the motion of an elbow or knee joint. And a
The Southwest RETORT
14
From the ACS Press Room circuit powered by a small battery heated up “Edible, Fluorescent Silk the printed pattern to above 120 F in less than a minute. The LM-alginate ink can be Tags” recycled by soaking the fabric in a weak soContinued from page 11 dium hydroxide solution, recovering fresh because some liquid medications are alcoliquid metal for new applications. hol-based, the researchers placed a coded The authors acknowledge funding from the silk film in a clear bottle of Scotch whisky, National Natural Science Foundation of China and the National Key Research and De- and found that the fluorescent code was still readable with the app. Finally, the researchvelopment Program of Zhejiang Province. ers showed that the fluorescent silk proteins are broken down by gastrointestinal enzymes, suggesting that the silk codes are not “Earthworms” only edible but also can be digested by the Continued from page 12 body. The researchers say that placing these edible code appliqués onto pills or in liquid mixed with either microscopic PLA or PET doses could empower patients and their care particles. Analysis of the creatures’ excre- providers to avoid the unintentional contions showed that their digestive systems sumption of fake treatments. broke down PLA into much smaller fragments than was observed with PET plastics. The authors acknowledge funding from the The animals also excreted PLA much more Cooperative Research Program for Agriculslowly. The researchers say the results ture Science & Technology Development show that earthworms can promote the from Rural Development Administration of breakdown of bioplastics, such as PLA, in the Republic of Korea, the U.S. Air Force soil. They add that more studies are needed Office of Scientific Research and the Trask to determine how the slow excretion of Innovation Fund from Purdue University. PLA fragments affects the health of these Silkworms can produce edible, fluorescent animals and whether the worms are an op- silk cocoons (left side of left image); the tion to remove degradable plastics from the proteins from the cocoons can be used in environment. codes (right) to verify the authenticity of The authors acknowledge funding from a medications. National Key Research and Development Project of China, the National Natural Science Foundation of China, the Tianjin Municipal Science and Technology Bureau, the Ministry of Education (China) and the Tianjin Research Innovation Project for Postgraduate Students. May 2022
The Southwest RETORT
15
Around the Area UT-Arlington Adjunct Professor E. Thomas Strom has been chosen as one of the initial HIST Fellows. The program honors members of the ACS Division of the History of Chemistry who have made a significant impact on the advancement of history in the chemical sciences as well as given dedicated service to the History Division. This initial group consists of ten Fellows. Tom was also chosen in 2009 as one of the initial group of ACS Fellows.
UT-Dallas Professor Ray Baughman, Robert A. Welch Chair in Chemistry, was awarded a $450K grant from the Air Force Office of Scientific Research for developing Faster, Stronger, More Powerful, and More Efficient Large-stroke Electrochemical, Thermal, and Fuelpowered Yarn- and Fiber-based Artificial Muscles.
orescence Imaging-guided Partial Nephrectomy with ClearGold nanoparticles) and a $368K NIH-STTR grant (Advance Early Detection of Lupus Nephritis with ClearGold nanoparticles). Associate Professor Jeremiah Gassensmith was awarded three grants, one from the Robert A. Welch Foundation, and two from Noble Panacea Labs (Enzymatically cleavable dendrimers for slow release of active ingredients in skincare products ($80K) and Tunable, Photodegradable Polymers for Cargo Delivery in Cosmetics ($72K)). Assistant Professor Sheena D’Arcy and Assistant Professor of Instruction Sumudu Wijenayake won UT Dallas School of Natural Sciences and Mathematics Teaching Awards for research professors and senior lecturers, respectively. Zhong Wang (graduate student in the Baughman Group) won the Best Dissertation Award in the School of Natural Sciences and Mathematics for 2022. Professor Kenneth J. Balkus, Jr. won the 2022 Robert H. Goddard Alumni Award for Outstanding Professional Achievement from Worcester Polytechnic Institute.
Professor Jie Zheng, Cecil H. and Ida Green Professor in Systems Biology Science and ClearNano Inc. were awarded a $100K NIH-SBIR grant (Advancing FluMay 2022
The Southwest RETORT
16
From the Editor I don’t know about you, but the last issue of the Retort year always sneaks up and surprises me...and here we are. My favorite article this month is from Environmental Science & Technology...turns out that earthworms eat plastics in the soil. The worms preferred soils with bio-based polylactic acid (PLA) particles or petroleum-derived polyethylene terephthalate (PET) particles but actively avoided some semi-synthetic plastics. When the soil was spiked with monomers of PLA and PET, the worms were also attracted, suggesting that the animals were drawn in by the odors as potential cues for food. But we don’t really know how it turns out; how is it digested? IS it digested? This may eventually be a great boon for the environment and soil clean-up. One of my committee members in grad school, the late Ezzat Yonathan, often said that if you couldn’t get some decent results on a new project over the summer semester (ie, no classes!), you should drop it. I think about this every May; he was usually right, so just in case that’s your summer plan, keep it in mind! Have a great summer.
May 2022
The Southwest RETORT
17
