SACNAS NATIONAL DIVERSITY IN STEM CONFERENCE
October 31st – November 2nd, 2024 in Phoenix Arizona
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The largest multidisciplinary and multicultural STEM diversity event in the country, the SACNAS conference is a gathering which serves to equip, empower, and energize participants for their academic and professional paths in STEM. Over the course of the event, college-level through professional attendees are immersed in cutting-edge STEM research, professional development sessions, motivational keynote speakers, and the Graduate School & Career Expo Hall, as well as multicultural celebrations and traditions, and an inclusive and welcoming community of peers, mentors, and role models. Simply put, the SACNAS conference is a broadly inclusive space where you are encouraged and empowered to bring your whole self to STEM.
Presentations From Previous TAMU Chapter Members
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Here we attempt to archive some of our chapter's participation at the national conference but we apologize if some information or dates are missing.
Fabian Leon
October 27 – 29, 2022 in San Juan, Puerto Rico, SACNAS Travel Grant Recipient
Historical Multi-Environmental Trials Reveal Elite Grain Sorghum Hybrid Trends from 1970-2021
in Texas
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Fabian Leon a , Lorin Harvey b , William L. Rooney a
a Department of Soil and Crop Sciences, Texas A&M University, College Station, TX 77843, USA
b North Mississippi Research and Extension Center - Pontotoc Branch Experiment Station, Mississippi
State University, Pontotoc, MS 38863, USA
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Sorghum (Sorghum bicolor [L. Moench]) is among the most important cereal crops worldwide and is
widely grown across Texas’ diverse geographies and production systems. Effective sorghum breeding
programs select to improve both profitability and adaptation of the grain crop and increases in grain yield
are ultimate measure of progress. Using the 60+ year history of sorghum hybrid improvement and yield
testing in the Texas A&M AgriLife system, the objective of this research was to retrospectively assess
trends of grain sorghum improvement with data from the AgriLife Research Crop Testing program. Data
from over 4,094 hybrids were evaluated between 1970 to 2021 over a total of 514 county-year
environments. For the hybrids entered in each year, the hybrids represented the commercially available
industry hybrids as well as industry and public experimental hybrids in the final stages of testing. A linear
mixed model approach was conducted to produce best linear unbiased predictions of genotypic and
environmental effects for grain yield and other relevant agronomic traits. These measures, as well as the
raw data, were used to inform and visualize trait dependencies, yield gains, and geographic regions with
similar effects on hybrid performance. Over this time, grain yield increased at a rate of 0.03 t ha -1 per year
and an average rate of genetic gain of 0.001 t ha -1 per year. A strong positive relationship between hybrid
yield and plant height was present with yield increases occurring in the 1980’s and 1990’s and a
sinusoidal pattern of yield performance since the year 2000. Principal component analysis clustered
counties in the Blacklands and Upper Coast regions, which are higher yielding due to higher rainfall,
separate from the Northern Plains and Rio Grande Valley regions, which have lower yields, due to less
rainfall. While latitude and production systems are factors in adaptation to a particular region, the results
herein indicate that modest increases in height will increase yield and that available moisture is the
preeminent delineator for production environments and their effects on elite grain sorghum hybrid
performance.
Karina Morales
"Characterizing a rice diversity panel with a 7K SNP chip and flowering time evaluation"
Karina Y. Morales, Stephon Warren, John Carlos Ignacio, Yuxin Shi, Rodante Tabien, Tobias Kretzchmar, Susan McCouch, Michael Thomson
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Rice (Oryza sativa L.) is an essential food crop with demands for increased yield as it provides the daily caloric intake of over 50% of the world’s growing population. Flowering is one of the most sensitive stages of rice growth and is highly variable among varieties and across environments. In Texas, farmers often desire early flowering varieties as these can avoid peak temperatures of the summer months and give sufficient time for the ratoon crop to mature before the cold temperatures of winter begin. This experiment took place at the Texas A&M AgriLife Research Center in Beaumont, TX where 208 rice varieties of diverse origins were grown in summer of 2017 and 2018. Beginning approximately 50 days after planting, notes were collected once a week on flowering percentage to estimate days to 50% flowering. Each variety was genotyped using the Illumina 7K rice SNP chip developed at Cornell University. During the 2017 season 6 significant loci were identified that contribute to days to flowering. Of these 6 loci, 1 co-localized with 2 known flowering time genes. We plan to perform genome editing on these two genes using the CRISPR/Cas9 system in the Texas variety Presidio.
Maliha Batool
"Identification of surface epitopes associated with protection against highly immune-evasive VlsE-expressing Lyme disease spirochetes"
Maliha Batool1, Salvador Eugenio C. Caoili2, Lawrence J. Dangott3, Ekaterina Gerasimov4, Yurij Ionov5, Helen Piontkivska6, Alex Zelikovsky4,7, Suryakant D. Waghela1, Artem S. Rogovsky
Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843
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The tick-borne pathogen, Borrelia burgdorferi, is responsible for approximately 300,000 Lyme disease (LD) cases per year in the United States. Recent increases in the number of LD cases in addition to the spread of the tick vector and a lack of vaccine highlights an urgent need for designing and developing an efficacious LD vaccine. Identification of protective epitopes that could be used to develop a second-generation vaccine is therefore imperative. Despite the antigenicity of several lipoproteins and integral outer membrane proteins (OMPs) on B. burgdorferi surface, the spirochetes successfully evade host antibodies primarily due to the VlsE-mediated antigenic variation. VlsE is thought to sterically block antibody access to protective epitopes of B. burgdorferi. However, it is highly unlikely that VlsE shields the entire surface epitome. Thus, identification of subdominant epitope targets that induce protection, when made dominant, is necessary to generate a good effective vaccine. Towards the identification, we repeatedly immunized immunocompetent mice with live-attenuated VlsE-deleted B. burgdorferi and then challenged the animals with VlsE-expressing (host-adapted) wild type. Passive immunization and western blot data suggested that the protection of the 50% of repeatedly-immunized animals against the highly immune-evasive B. burgdorferi was antibody-mediated. Comparison of serum antibody repertoires identified in protected and non-protected animals permitted the identification of several putative epitopes significantly associated with the protection. Most of the linear putative epitopes were conserved between the main pathogenic Borrelia genospecies and found within known subdominant regions of OMPs. Currently, immunization studies testing whether the protection-associated epitopes are protective under way.
Grace Villalpando
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More than 40% of the world’s energy consumption occurs within buildings and a significant fraction of these costs are associated with the lighting of interiors. The replacement of fluorescent compacts with solid-state light-emitting diodes (LEDs) is expected to bring about an almost five-fold reduction of energy consumption. However, there is a strong need to develop red, green, and blue phosphors that can be coupled with blue LEDs to generate white light. Rare-earth oxychlorides (REOCl) show great promise as color tunable phosphors given their ability to readily accommodate multiple luminescent centers. These compounds crystallize in a structural motif that alternates cationic (REO)n n+ and anionic (Cl- ) layers and allows for efficacious energy transfer to luminescent rare-earth dopant atoms. These compounds are further characterized by a low maximum phonon cutoff energy and exhibit high chemical stability. An ongoing challenge that is the focus of my research is the development of synthetic methods for the controllable incorporation of multiple luminescent centers within the oxychloride lattice. The synthesis of solid-solution REOCl nanocrystals has been performed using the nonhydrolytic sol—gel condensation of trivalent rare-earth alkoxides and rare-earth chlorides. Luminescent centers have been incorporated by substituting a desired molar equivalent of the dopant rare-earth chloride (Eu3+ , Eu2+ , and Tb3+ ) with the lanthanum chloride precursor. The prepared nanocrystals have been characterized via X-ray diffraction, transmission electron microscopy, spectrofluorescence, and inductively coupled plasma-mass spectrometry. The judicious incorporation of dopants allows for precise control over the emission wavelength, lifetime, and photoluminescence intensity of the obtained materials.