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Full-Text Articles in Life Sciences

Automatic Camera Trap Classification Using Wildlife-Specific Deep Learning In Nilgai Management, Matthew Kutugata, Jeremy Baumgardt, John A. Goolsby, Alexis Racelis Dec 2021

Automatic Camera Trap Classification Using Wildlife-Specific Deep Learning In Nilgai Management, Matthew Kutugata, Jeremy Baumgardt, John A. Goolsby, Alexis Racelis

Biology Faculty Publications and Presentations

Camera traps provide a low-cost approach to collect data and monitor wildlife across large scales but hand-labeling images at a rate that outpaces accumulation is difficult. Deep learning, a subdiscipline of machine learning and computer science, has been shown to address the issue of automatically classifying camera trap images with a high degree of accuracy. This technique, however, may be less accessible to ecologists, to small scale conservation projects, and has serious limitations. In this study, a simple deep learning model was trained using a dataset of 120,000 images to identify the presence of nilgai Boselaphus tragocamelus, a regionally specific …


Examining The Role Of Buzzing Time And Acoustics On Pollen Extraction Of Solanum Elaeagnifolium, Mandeep Tayal, Rupesh R. Kariyat Nov 2021

Examining The Role Of Buzzing Time And Acoustics On Pollen Extraction Of Solanum Elaeagnifolium, Mandeep Tayal, Rupesh R. Kariyat

Biology Faculty Publications and Presentations

Buzz pollination is a specialized pollination syndrome that requires vibrational energy to extract concealed pollen grains from poricidal anthers. Although a large body of work has examined the ecology of buzz pollination, whether acoustic properties of buzz pollinators affect pollen extraction is less understood, especially in weeds and invasive species. We examined the pollination biology of Silverleaf nightshade (Solanum elaeagnifolium), a worldwide invasive weed, in its native range in the Lower Rio Grande Valley (LRGV) in south Texas. Over two years, we documented the floral visitors on S. elaeagnifolium, their acoustic parameters (buzzing amplitude, frequency, and duration of buzzing) and …


A Sugarcane G-Protein-Coupled Receptor, Shgpcr1, Confers Tolerance To Multiple Abiotic Stresses, Manikandan Ramasamy, Mona B. Damaj, Carol Vargas-Bautista, Victoria Mora, Jiaxing Liu, Carmen S. Padilla, Sonia Irigoyen, Tripti Saini, Nirakar Sahoo, Jorge A. Dasilva, Kranthi K. Mandadi Nov 2021

A Sugarcane G-Protein-Coupled Receptor, Shgpcr1, Confers Tolerance To Multiple Abiotic Stresses, Manikandan Ramasamy, Mona B. Damaj, Carol Vargas-Bautista, Victoria Mora, Jiaxing Liu, Carmen S. Padilla, Sonia Irigoyen, Tripti Saini, Nirakar Sahoo, Jorge A. Dasilva, Kranthi K. Mandadi

Biology Faculty Publications and Presentations

Sugarcane (Saccharum spp.) is a prominent source of sugar and serves as bioenergy/biomass feedstock globally. Multiple biotic and abiotic stresses, including drought, salinity, and cold, adversely affect sugarcane yield. G-protein-coupled receptors (GPCRs) are components of G-protein-mediated signaling affecting plant growth, development, and stress responses. Here, we identified a GPCR-like protein (ShGPCR1) from sugarcane and energy cane (Saccharum spp. hybrids) and characterized its function in conferring tolerance to multiple abiotic stresses. ShGPCR1 protein sequence contained nine predicted transmembrane (TM) domains connected by four extracellular and four intracellular loops, which could interact with various ligands and heterotrimeric G …


Pi3k Pathway Inhibition With Nvp-Bez235 Hinders Glycolytic Metabolism In Glioblastoma Multiforme Cells, Shreya Udawant, Carl Litif, Alma Lopez, Bonnie Gunn, Erin Schuenzel, Megan Keniry Nov 2021

Pi3k Pathway Inhibition With Nvp-Bez235 Hinders Glycolytic Metabolism In Glioblastoma Multiforme Cells, Shreya Udawant, Carl Litif, Alma Lopez, Bonnie Gunn, Erin Schuenzel, Megan Keniry

Biology Faculty Publications and Presentations

Glioblastoma (GBM) is the most lethal primary brain cancer that lacks effective molecular targeted therapies. The PI3K/AKT/mTOR pathway is activated in 90% of all Glioblastoma multiforme (GBM) tumors. To gain insight into the impact of the PI3K pathway on GBM metabolism, we treated U87MG GBM cells with NVP-BEZ235 (PI3K and mTOR a dual inhibitor) and identified differentially expressed genes with RNA-seq analysis. RNA-seq identified 7803 differentially regulated genes in response to NVP-BEZ235. Gene Set Enrichment Analysis (GSEA) identified two glycolysis-related gene sets that were significantly enriched (p < 0.05) in control samples compared to NVP-BEZ235-treated samples. We validated the inhibition of glycolytic genes by NVP-BEZ235 and examined the impact of the FOXO1 inhibitor (AS1842856) on these genes in a set of GBM cell lines. FOXO1 inhibition alone was associated with reduced LDHA expression, but not ENO1 or PKM2. Bioinformatics analyses revealed that PI3K-impacted glycolytic genes were over-expressed and co-expressed in GBM clinical samples. The elevated expression of PI3K-impacted glycolytic genes was associated with poor prognosis in GBM based on Kaplan–Meier survival analyses. Our results suggest novel insights into hallmark metabolic reprogramming associated with the PI3K-mTOR dual inhibition.


Morphological Characterization Of Trichomes Shows Enormous Variation In Shape, Density And Dimensions Across The Leaves Of 14 Solanum Species, Sakshi Watts, Rupesh R. Kariyat Nov 2021

Morphological Characterization Of Trichomes Shows Enormous Variation In Shape, Density And Dimensions Across The Leaves Of 14 Solanum Species, Sakshi Watts, Rupesh R. Kariyat

Biology Faculty Publications and Presentations

Trichomes are the epidermal appendages commonly observed on plant surfaces including leaves, stem and fruits. Plant trichomes have been well studied as a structural plant defence designed to protect plants against abiotic and biotic stressors such as UV rays, temperature extremities and herbivores. Trichomes are primarily classified into glandular and non-glandular trichomes, based on the presence or absence of a glandular head. The plant genus Solanum is the largest genus of family Solanaceae that houses ~3500 species of ecological and economic importance have a diverse set of trichomes that vary in density and morphology. However, due to the incomplete and …


Desktop Scanning Electron Microscopy In Plant-Insect Interactions Research: A Fast And Effective Way To Capture Electron Micrographs With Minimal Sample Preparation, Sakshi Watts, Ishveen Kaur, Sukhman Singh, Bianca Jimenez, Jesus Chavana, Rupesh R. Kariyat Oct 2021

Desktop Scanning Electron Microscopy In Plant-Insect Interactions Research: A Fast And Effective Way To Capture Electron Micrographs With Minimal Sample Preparation, Sakshi Watts, Ishveen Kaur, Sukhman Singh, Bianca Jimenez, Jesus Chavana, Rupesh R. Kariyat

Biology Faculty Publications and Presentations

The ability to visualize cell and tissue morphology at a high magnification using scanning electron microscopy (SEM) has revolutionized plant sciences research. In plant-insect interactions studies, SEM based imaging has been of immense assistance to understand plant surface morphology including trichomes (plant hairs; physical defense structures against herbivores (Kaur and Kariyat, 2020a, 2020b; Watts and Kariyat, 2021), spines, waxes, and insect morphological characteristics such as mouth parts, antennae, and legs, that they interact with. While SEM provides finer details of samples, and the imaging process is simpler now with advanced image acquisition and processing, sample preparation methodology has lagged. The …


Ten Strategies For Avoiding And Overcoming Authorship Conflicts In Academic Publishing, S J. Cooke, N Young, M R. Donaldson, E A. Nyboer, D G. Roche, C L. Madliger, R J. Lennox, J M. Chapman, Zen Faulkes, J R. Bennett Oct 2021

Ten Strategies For Avoiding And Overcoming Authorship Conflicts In Academic Publishing, S J. Cooke, N Young, M R. Donaldson, E A. Nyboer, D G. Roche, C L. Madliger, R J. Lennox, J M. Chapman, Zen Faulkes, J R. Bennett

Biology Faculty Publications and Presentations

For better or for worse, authorship is a currency in scholarly research and advancement. In scholarly writing, authorship is widely acknowledged as a means of conferring credit but is also tied to concepts such as responsibility and accountability. Authorship is one of the most divisive topics both at the level of the research team and more broadly in the academy and beyond. At present, authorship is often the primary way to assert and receive credit in many scholarly pursuits and domains. Debates rage, publicly but mostly privately, regarding authorship. Here we attempt to clarify key concepts related to authorship informed …


Detecting Forest Response To Droughts With Global Observations Of Vegetation Water Content, Alexandra G. Konings, Sassan S. Saatchi, Christian Frankenberg, Michael Keller, Victor Leshyk, William R. L. Anderegg, Vincent Humphrey, Ashley M. Matheny, Anna Trugman, Bradley O. Christoffersen Sep 2021

Detecting Forest Response To Droughts With Global Observations Of Vegetation Water Content, Alexandra G. Konings, Sassan S. Saatchi, Christian Frankenberg, Michael Keller, Victor Leshyk, William R. L. Anderegg, Vincent Humphrey, Ashley M. Matheny, Anna Trugman, Bradley O. Christoffersen

Biology Faculty Publications and Presentations

Droughts in a warming climate have become more common and more extreme, making understanding forest responses to water stress increasingly pressing. Analysis of water stress in trees has long focused on water potential in xylem and leaves, which influences stomatal closure and water flow through the soil-plant-atmosphere continuum. At the same time, changes of vegetation water content (VWC) are linked to a range of tree responses, including fluxes of water and carbon, mortality, flammability, and more. Unlike water potential, which requires demanding in situ measurements, VWC can be retrieved from remote sensing measurements, particularly at microwave frequencies using radar and …


Effects Of Patch Size, Fragmentation, And Invasive Species On Plant And Lepidoptera Communities In Southern Texas, James A. Stilley, Christopher A. Gabler Aug 2021

Effects Of Patch Size, Fragmentation, And Invasive Species On Plant And Lepidoptera Communities In Southern Texas, James A. Stilley, Christopher A. Gabler

Biology Faculty Publications and Presentations

Simple Summary

Human land use has removed habitats, separated habitats into small and disconnected fragments, and introduced foreign species, which all harm wildlife. South Texas is highly diverse and home to many endangered species, but human disturbance threatens its wildlife. In south Texas, we poorly understand how different aspects of human land use influence wildlife diversity and abundance. We studied this by surveying plants and butterflies in 24 habitat fragments in south Texas that differed in size, shape, type, and land use history. Human disturbance was extensive, and foreign and weedy species were dominant in most habitats. Habitat types had …


Deciphering The Role Of Ion Channels In Early Defense Signaling Against Herbivorous Insects, Akanksha Gandhi, Rupesh R. Kariyat, Amaravadhi Harikishore, Marzieh Ayati, Anirban Bhunia, Nirakar Sahoo Aug 2021

Deciphering The Role Of Ion Channels In Early Defense Signaling Against Herbivorous Insects, Akanksha Gandhi, Rupesh R. Kariyat, Amaravadhi Harikishore, Marzieh Ayati, Anirban Bhunia, Nirakar Sahoo

Biology Faculty Publications and Presentations

Plants and insect herbivores are in a relentless battle to outwit each other. Plants have evolved various strategies to detect herbivores and mount an effective defense system against them. These defenses include physical and structural barriers such as spines, trichomes, cuticle, or chemical compounds, including secondary metabolites such as phenolics and terpenes. Plants perceive herbivory by both mechanical and chemical means. Mechanical sensing can occur through the perception of insect biting, piercing, or chewing, while chemical signaling occurs through the perception of various herbivore-derived compounds such as oral secretions (OS) or regurgitant, insect excreta (frass), or oviposition fluids. Interestingly, ion …


Use Of Its‑1 To Identify Bactrocera Dorsalis And Bactrocera Occipitalis (Diptera: Tephritidae): A Case Study Using Flies Trapped In California From 2008 To 2018, Norman B. Barr, Martin Hauser, Jennifer Belcher, David Salinas, Erin Schuenzel, Peter Kerr, Stephen Gaimari Aug 2021

Use Of Its‑1 To Identify Bactrocera Dorsalis And Bactrocera Occipitalis (Diptera: Tephritidae): A Case Study Using Flies Trapped In California From 2008 To 2018, Norman B. Barr, Martin Hauser, Jennifer Belcher, David Salinas, Erin Schuenzel, Peter Kerr, Stephen Gaimari

Biology Faculty Publications and Presentations

Molecular methods are necessary to diagnose immature life stages of the agricultural pest fruit fly Bactrocera dorsalis (Hendel), and are useful to corroborate identifications based on adults because morphological variation within the species can overlap with congeners. DNA sequencing of the nuclear ribosomal internal transcribed spacer 1 (ITS‑1) has been adopted by the International Plant Protection Convention as an internationally accepted method to distinguish between the 2 pestiferous fruit fly species Bactrocera dorsalis and Bactrocera carambolae (Drew & Hancock). Reported ITS‑1 sequences also are distinct and diagnostically informative to distinguish several other Bactrocera species related to B. dorsalis. In this …


Increasing Public Health Mosquito Surveillance In Hidalgo County, Texas To Monitor Vector And Arboviral Presence, Clarissa D. Guerrero, Steven Hinojosa, Diana Vanegas, Niko Tapangan, Matthew Guajardo, Sara Alaniz, Narda Cano, Christopher Vitek, John Thomas, Valerie Hernandez, Juan Garcia Jr. Aug 2021

Increasing Public Health Mosquito Surveillance In Hidalgo County, Texas To Monitor Vector And Arboviral Presence, Clarissa D. Guerrero, Steven Hinojosa, Diana Vanegas, Niko Tapangan, Matthew Guajardo, Sara Alaniz, Narda Cano, Christopher Vitek, John Thomas, Valerie Hernandez, Juan Garcia Jr.

Biology Faculty Publications and Presentations

From 2016 to 2018, Hidalgo County observed the emergence of Zika virus (ZIKV) infections along with sporadic cases of Dengue virus (DENV) and West Nile virus (WNV). Due to the emergence of ZIKV and the historical presence of other mosquito-borne illnesses, Hidalgo County obtained funding to enhance mosquito surveillance and educate residents on arboviruses and travel risks. During this time period, Hidalgo County mosquito surveillance efforts increased by 1.275%. This increase resulted in >8000 mosquitoes collected, and 28 mosquito species identified. Aedes aegypti, Ae albopictus and Culex quinquefasciatus made up approximately two-thirds of the mosquitoes collected in 2018 (4122/6171). Spatiotemporal …


Do Early-Successional Weeds Facilitate Or Compete With Seedlings In Forest Restoration? Disentangling Abiotic Versus Biotic Factors, Mylen Arias, Rupesh R. Kariyat, Kimberly Wahl-Villarreal, Stephany Mendez, Jesus Chavana, Bradley O. Christoffersen Aug 2021

Do Early-Successional Weeds Facilitate Or Compete With Seedlings In Forest Restoration? Disentangling Abiotic Versus Biotic Factors, Mylen Arias, Rupesh R. Kariyat, Kimberly Wahl-Villarreal, Stephany Mendez, Jesus Chavana, Bradley O. Christoffersen

Biology Faculty Publications and Presentations

  1. Semi-arid forests need cost-effective restoration strategies to address their severe degradation. Tree shelters are often used to minimize abiotic and biotic stress during seedling establishment. We asked if early-successional weeds act as a natural shelter by facilitating native seedlings, contingent on abiotic and biotic stressors and seedling ecological strategy.

  2. We conducted a manipulative weed exclusion experiment at a semi-arid site in South Texas targeted for large-scale forest restoration to discern the net effect of weeds on the growth and survival of target thornscrub tree and shrub seedlings. We assessed the roles of contrasting seedling ecological strategies (fast vs. slow growth …


Temperatures Influence Susceptibility To Insecticides In Aedes Aegypti And Aedes Albopictus (Diptera: Culicidae) Mosquitoes, Wendy S. Salinas, Teresa Patricia Feria-Arroyo, Christopher Vitek Aug 2021

Temperatures Influence Susceptibility To Insecticides In Aedes Aegypti And Aedes Albopictus (Diptera: Culicidae) Mosquitoes, Wendy S. Salinas, Teresa Patricia Feria-Arroyo, Christopher Vitek

Biology Faculty Publications and Presentations

Aedes aegypti and Aedes albopictus (Diptera: Culicidae) are vectors for several arboviruses, including dengue, Zika virus and chikungunya virus. The primary method of controlling these diseases is controlling the vector population, often with insecticides. Insecticide resistance may impact the success of these efforts. We tested the effect of variable temperature exposures on susceptibility to insecticides by exposing adult A. aegypti and A. albopictus to different temperatures and tested their susceptibility to insecticides. We hypothesized that adults maintained at high temperatures would show increased susceptibility to insecticides relative to lower temperatures. Colony mosquitoes were hatched, reared to adulthood and then maintained …


Assessing Climate Change Impacts On Live Fuel Moisture And Wildfire Risk Using A Hydrodynamic Vegetation Model, Wu Ma, Lu Zhai, Alexandria Pivovaroff, Jacquelyn Shuman, Polly Buotte, Junyan Ding, Bradley O. Christoffersen, Ryan G. Knox, Max Moritz, Rosie A. Fisher Jul 2021

Assessing Climate Change Impacts On Live Fuel Moisture And Wildfire Risk Using A Hydrodynamic Vegetation Model, Wu Ma, Lu Zhai, Alexandria Pivovaroff, Jacquelyn Shuman, Polly Buotte, Junyan Ding, Bradley O. Christoffersen, Ryan G. Knox, Max Moritz, Rosie A. Fisher

Biology Faculty Publications and Presentations

Live fuel moisture content (LFMC) plays a critical role in wildfire dynamics, but little is known about responses of LFMC to multivariate climate change, e.g., warming temperature, CO2 fertilization, and altered precipitation patterns, leading to a limited prediction ability of future wildfire risks. Here, we use a hydrodynamic demographic vegetation model to estimate LFMC dynamics of chaparral shrubs, a dominant vegetation type in fire-prone southern California. We parameterize the model based on observed shrub allometry and hydraulic traits and evaluate the model's accuracy through comparisons between observed and simulated LFMC of three plant functional types (PFTs) under current climate conditions. …


The Conservation Status Of The World’S Freshwater Molluscs, M. Böhm, N. I. Dewhurst-Richman, M. Seddon, C. Albrecht, D. Allen, A. E. Bogan, K. Cummings, G. Darrigran, W. Darwall, Kathryn E. Perez Jul 2021

The Conservation Status Of The World’S Freshwater Molluscs, M. Böhm, N. I. Dewhurst-Richman, M. Seddon, C. Albrecht, D. Allen, A. E. Bogan, K. Cummings, G. Darrigran, W. Darwall, Kathryn E. Perez

Biology Faculty Publications and Presentations

With the biodiversity crisis continuing unchecked, we need to establish levels and drivers of extinction risk, and reassessments over time, to effectively allocate conservation resources and track progress towards global conservation targets. Given that threat appears particularly high in freshwaters, we assessed the extinction risk of 1428 randomly selected freshwater molluscs using the IUCN Red List Categories and Criteria, as part of the Sampled Red List Index project. We show that close to one-third of species in our sample are estimated to be threatened with extinction, with highest levels of threat in the Nearctic, Palearctic and Australasia and among gastropods. …


Hydraulic Architecture Explains Species Moisture Dependency But Not Mortality Rates Across A Tropical Rainfall Gradient, Alexandria L. Pivovaroff, Brett T. Wolfe, Nate G. Mcdowell, Bradley O. Christoffersen, Stuart J. Davies, L. Turin Dickman, Charlotte Grossiord, Riley T. Leff, Alistair Rogers, Shawn P. Serbin Jun 2021

Hydraulic Architecture Explains Species Moisture Dependency But Not Mortality Rates Across A Tropical Rainfall Gradient, Alexandria L. Pivovaroff, Brett T. Wolfe, Nate G. Mcdowell, Bradley O. Christoffersen, Stuart J. Davies, L. Turin Dickman, Charlotte Grossiord, Riley T. Leff, Alistair Rogers, Shawn P. Serbin

Biology Faculty Publications and Presentations

Intensified droughts are affecting tropical forests across the globe. However, the underlying mechanisms of tree drought response and mortality are poorly understood. Hydraulic traits and especially hydraulic safety margins (HSMs), that is, the extent to which plants buffer themselves from thresholds of water stress, provide insights into species-specific drought vulnerability. We investigated hydraulic traits during an intense drought triggered by the 2015–2016 El Niño on 27 canopy tree species across three tropical forest sites with differing precipitation. We capitalized on the drought event as a time when plant water status might approach or exceed thresholds of water stress. We investigated …


Walking Velocity And Estimated Distance Of The Armored Scale Crawler Rhizaspidiotus Donacis, A Biological Control Agent For Arundo Donax, Joshua A. Villarreal, Alexis Racelis, John A. Goolsby Jun 2021

Walking Velocity And Estimated Distance Of The Armored Scale Crawler Rhizaspidiotus Donacis, A Biological Control Agent For Arundo Donax, Joshua A. Villarreal, Alexis Racelis, John A. Goolsby

Biology Faculty Publications and Presentations

Arundo scale, Rhizaspidiotus donacis (Leonardi) (Hemiptera: Diaspididae), is an armored scale biological control agent established on the invasive weed, Arundo donax L. (Poaceae; Arundinoideae) at several locations along the Rio Grande in Texas (Goolsby et. al. 2009, Moran and Goolsby 2010, Goolsby et al. 2011, Villarreal et al. 2016). The arundo scale is having significant impact on the target weed in areas where it established (Goolsby and Moran 2019), and no non-target plant use was observed (Goolsby et al. 2020). Armored scale crawlers usually live for less than a day and …


Infectious Disease Transmission By Arline Travel, Daniele Provenzano, Sofy Barocio May 2021

Infectious Disease Transmission By Arline Travel, Daniele Provenzano, Sofy Barocio

Biology Faculty Publications and Presentations

Improvements in aviation technology have led to considerable growth of domestic and international flights worldwide especially during the past four decades. Commercial flights have increased the movement of and have connected people from virtually all corners of the globe since the end of World War II to exceed 3 billion passengers a year since 2013: a sizable proportion of the global human population. Flight times have decreased considerably from the onset of commercial aviation and the range of airliners has extended substantially. A passenger harboring an infectious agent embarking a flight on one continent can be deplaning on another continent …


Disentangling The Effects Of Vapor Pressure Deficit And Soil Water Availability On Canopy Conductance In A Seasonal Tropical Forest During The 2015 El Niño Drought, Yilin Fang, L. Ruby Leung, Brett T. Wolfe, Matteo Detto, Ryan G. Knox, Bryan Powell, Charlotte Grossiord, Chonggang Xu, Bradley O. Christoffersen, Pierre Gentine May 2021

Disentangling The Effects Of Vapor Pressure Deficit And Soil Water Availability On Canopy Conductance In A Seasonal Tropical Forest During The 2015 El Niño Drought, Yilin Fang, L. Ruby Leung, Brett T. Wolfe, Matteo Detto, Ryan G. Knox, Bryan Powell, Charlotte Grossiord, Chonggang Xu, Bradley O. Christoffersen, Pierre Gentine

Biology Faculty Publications and Presentations

Water deficit in the atmosphere and soil are two key interactive factors that constrain transpiration and vegetation productivity. It is not clear which of these two factors is more important for the water and carbon flux response to drought stress in ecosystems. In this study, field data and numerical modeling were used to isolate their impact on evapotranspiration (ET) and gross primary productivity (GPP) at a tropical forest site in Barro Colorado Island (BCI), Panama, focusing on their response to the drought induced by the El Niño event of 2015–2016. Numerical simulations were performed using a plant hydrodynamic scheme (HYDRO) …


Understanding Water And Energy Fluxes In The Amazonia: Lessons From An Observation-Model Intercomparison, Natalia Restrepo-Coupe, Loren P. Albert, Marcos Longo, Ian Baker, Naomi M. Levine, Lina M. Mercado, Alessandro C. Da Araujo, Bradley O. Christoffersen, Marcos H. Costa, David R. Fitzjarrald May 2021

Understanding Water And Energy Fluxes In The Amazonia: Lessons From An Observation-Model Intercomparison, Natalia Restrepo-Coupe, Loren P. Albert, Marcos Longo, Ian Baker, Naomi M. Levine, Lina M. Mercado, Alessandro C. Da Araujo, Bradley O. Christoffersen, Marcos H. Costa, David R. Fitzjarrald

Biology Faculty Publications and Presentations

Tropical forests are an important part of global water and energy cycles, but the mechanisms that drive seasonality of their land-atmosphere exchanges have proven challenging to capture in models. Here, we (1) report the seasonality of fluxes of latent heat (LE), sensible heat (H), and outgoing short and longwave radiation at four diverse tropical forest sites across Amazonia—along the equator from the Caxiuanã and Tapajós National Forests in the eastern Amazon to a forest near Manaus, and from the equatorial zone to the southern forest in Reserva Jaru; (2) investigate how vegetation and climate influence these fluxes; and …


Civic Agriculture In Review: Then, Now, And Future Directions, Allison Kaika, Alexis Racelis Apr 2021

Civic Agriculture In Review: Then, Now, And Future Directions, Allison Kaika, Alexis Racelis

Biology Faculty Publications and Presentations

"Civic agriculture," a term first coined by rural sociologist Thomas Lyson, refers to forms of agriculture that occur on a local level, from production to consumption, and are linked to a community's social and economic development. Sixteen years since its original articulation, the term "civic agriculture" has taken on greater significance in research, political activism, and community organizing. Grown from the roots of civic community theory, civic agriculture functions as a new branch of civic community theory that is ripe for theorization. In revisiting the foundations of the term, this review paper seeks to consolidate current and future research in …


A Method For Repeated, Longitudinal Sampling Of Individual Aedes Aegypti For Transmission Potential Of Arboviruses, E. Handly Mayton, Heather Hernandez, Christopher Vitek, Rebecca C. Christofferson Mar 2021

A Method For Repeated, Longitudinal Sampling Of Individual Aedes Aegypti For Transmission Potential Of Arboviruses, E. Handly Mayton, Heather Hernandez, Christopher Vitek, Rebecca C. Christofferson

Biology Faculty Publications and Presentations

Mosquito-borne viruses are the cause of significant morbidity and mortality worldwide, especially in low- and middle-income countries. Assessing risk for viral transmission often involves characterization of the vector competence of vector–virus pairings. The most common determination of vector competence uses discreet, terminal time points, which cannot be used to investigate variation in transmission aspects, such as biting behavior, over time. Here, we present a novel method to longitudinally measure individual biting behavior and Zika virus (ZIKV) transmission. Individual mosquitoes were exposed to ZIKV, and from 9 to 24 days post-exposure, individuals were each offered a 180 μL bloodmeal every other …


Mitochondrial Oma1 And Opa1 As Gatekeepers Of Organellar Structure/Function And Cellular Stress Response, Robert Gilkerson, Patrick De La Torre, Shaynah St. Vallier Mar 2021

Mitochondrial Oma1 And Opa1 As Gatekeepers Of Organellar Structure/Function And Cellular Stress Response, Robert Gilkerson, Patrick De La Torre, Shaynah St. Vallier

Biology Faculty Publications and Presentations

Mammalian mitochondria are emerging as a critical stress-responsive contributor to cellular life/death and developmental outcomes. Maintained as an organellar network distributed throughout the cell, mitochondria respond to cellular stimuli and stresses through highly sensitive structural dynamics, particularly in energetically demanding cell settings such as cardiac and muscle tissues. Fusion allows individual mitochondria to form an interconnected reticular network, while fission divides the network into a collection of vesicular organelles. Crucially, optic atrophy-1 (OPA1) directly links mitochondrial structure and bioenergetic function: when the transmembrane potential across the inner membrane (ΔΨm) is intact, long L-OPA1 isoforms carry out fusion of the mitochondrial …


Local Adaptation To Continuous Mowing Makes The Noxious Weed Solanum Elaeagnifolium A Superweed Candidate By Improving Fitness And Defense Traits, Jesus Chavana, Sukhman Singh, Alejandro Vazquez, Bradley O. Christoffersen, Alexis Racelis, Rupesh R. Kariyat Mar 2021

Local Adaptation To Continuous Mowing Makes The Noxious Weed Solanum Elaeagnifolium A Superweed Candidate By Improving Fitness And Defense Traits, Jesus Chavana, Sukhman Singh, Alejandro Vazquez, Bradley O. Christoffersen, Alexis Racelis, Rupesh R. Kariyat

Biology Faculty Publications and Presentations

The role of disturbance in accelerating weed growth is well understood. While most studies have focused on soil mediated disturbance, mowing can also impact weed traits. Using silverleaf nightshade (Solanum elaeagnifolium), a noxious and invasive weed, through a series of field, laboratory, and greenhouse experiments, we asked whether continuous mowing influences growth and plant defense traits, expressed via different avenues, and whether they cascade into offspring. We found that mowed plants produced significantly less number of fruits, and less number of total seeds per plant, but had higher seed mass, and germinated more and faster. When three herbivores …


Importation And Preliminary Evaluation Of The Stem Boring Moth Buakea Kaeuae As A Potential Biological Control Agent Of Invasive Guineagrass, Megathyrsus Maximus, Ann T. Vacek, John A. Goolsby, Paul-Andre Calatayud, Bruno Le Ru, Boaz Musyoka, Rupesh R. Kariyat Mar 2021

Importation And Preliminary Evaluation Of The Stem Boring Moth Buakea Kaeuae As A Potential Biological Control Agent Of Invasive Guineagrass, Megathyrsus Maximus, Ann T. Vacek, John A. Goolsby, Paul-Andre Calatayud, Bruno Le Ru, Boaz Musyoka, Rupesh R. Kariyat

Biology Faculty Publications and Presentations

Abstract. Guineagrass, Megathyrsus maximus (Jacq.) B.K.Simon & S.W.L.Jacobs, is an African grass that is invasive in Florida, Hawaii, southern Texas, and northeastern Mexico. Buakea kaeuae Moyal et al., a stem-boring African moth found only on M. maximus, was imported from Kenya and evaluated for its ability to feed and develop on Guineagrass naturalized in southern Texas. Neither larvae nor adults developed or reproduced on Texas Guineagrass.

Resumen. El zacate Guinea (Megathyrsus maximus (Jacq.) B.K.Simon & S.W.L.Jacobs), originario de África, es considerado invasivo en Florida, Hawaii, sur de Texas, y noreste de México. Buakea kaeuae Moyal et al. es una …


Mitochondrial Opa1 Cleavage Is Reversibly Activated By Differentiation Of H9c2 Cardiomyoblasts, Iraselia Garcia, Fredy Calderon, Patrick De La Torre, Shaynah St. Vallier, Cristobal Rodriguez, Divya Agarwala, Megan Keniry, Wendy Innis-Whitehouse, Robert Gilkerson Mar 2021

Mitochondrial Opa1 Cleavage Is Reversibly Activated By Differentiation Of H9c2 Cardiomyoblasts, Iraselia Garcia, Fredy Calderon, Patrick De La Torre, Shaynah St. Vallier, Cristobal Rodriguez, Divya Agarwala, Megan Keniry, Wendy Innis-Whitehouse, Robert Gilkerson

Biology Faculty Publications and Presentations

Optic atrophy-1 (OPA1) is a dynamin-like GTPase localized to the mitochondrial inner membrane, playing key roles in inner membrane fusion and cristae maintenance. OPA1 is regulated by the mitochondrial transmembrane potential (Δψm): when Δψm is intact, long OPA1 isoforms (L-OPA1) carry out inner membrane fusion. Upon loss of Δψm, L-OPA1 isoforms are proteolytically cleaved to short (S-OPA1) isoforms by the stress-inducible OMA1 metalloprotease, causing collapse of the mitochondrial network and promoting apoptosis. Here, we show that L-OPA1 isoforms of H9c2 cardiomyoblasts are retained under loss of Δψm, despite the presence of OMA1. However, when H9c2s are differentiated to a more …


Biotic Homogenization Or Riparian Refugia? Urban And Wild Land Snail Assemblages Along A Subtropical Precipitation Gradient, Kathryn E. Perez, Briante S. Lewis Najev, Bradley O. Christoffersen, Jeffrey C. Nekola Feb 2021

Biotic Homogenization Or Riparian Refugia? Urban And Wild Land Snail Assemblages Along A Subtropical Precipitation Gradient, Kathryn E. Perez, Briante S. Lewis Najev, Bradley O. Christoffersen, Jeffrey C. Nekola

Biology Faculty Publications and Presentations

A noted impact of urbanization is the tendency for biotic homogenization, or the increase of similarity of geographically disparate communities. On the other hand, some urban habitats harbor biodiversity native to their region, a role potentially important in xeric landscapes, with irrigation increasing the coverage and availability of mesic habitats in an otherwise water-limited landscape. We assessed the relative importance of urban yards as agents of biotic homogenization or riparian refugia by characterizing community composition of Tamaulipan thornforest land snail assemblages across a pronounced precipitation gradient in far south Texas, USA. We quantified α- and β-diversity and assessed whether the …


Nvp-Bez235 Or Jaki Treatment Leads To Decreased Survival Of Examined Gbm And Bbc Cells, Neftali Vazquez, Alma Lopez, Victoria Cuello, Michael W. Persans, Erin Schuenzel, Wendy Innis-Whitehouse, Megan Keniry Feb 2021

Nvp-Bez235 Or Jaki Treatment Leads To Decreased Survival Of Examined Gbm And Bbc Cells, Neftali Vazquez, Alma Lopez, Victoria Cuello, Michael W. Persans, Erin Schuenzel, Wendy Innis-Whitehouse, Megan Keniry

Biology Faculty Publications and Presentations

Cancer cells almost universally harbor constitutively active Phosphatidylinositol-3 Kinase (PI3K) Pathway ac-tivity via mutation of key signaling components and/or epigenetic mechanisms. Scores of PI3K Pathway in-hibitors are currently under investigation as putative chemotherapeutics. However, feedback and stem cell mechanisms induced by PI3K Pathway inhibition can lead to reduced treatment efficacy. To address therapeutic barriers, we examined whether JAKi would reduce stem gene expression in a setting of PI3K Pathway inhibition in order to improve treatment efficacy. We targeted the PI3K Pathway with NVP-BEZ235 (dual PI3K and mTOR inhibitor) in combination with the Janus Kinase inhibitor JAKi in glioblastoma (GBM) and …


An Ecotoxicological Approach To Microplastics On Terrestrial And Aquatic Organisms: A Systematic Review In Assessment, Monitoring And Biological Impact, Omar A. Vazquez, Saydur Rahman Feb 2021

An Ecotoxicological Approach To Microplastics On Terrestrial And Aquatic Organisms: A Systematic Review In Assessment, Monitoring And Biological Impact, Omar A. Vazquez, Saydur Rahman

Biology Faculty Publications and Presentations

Marine and land plastic debris biodegrades at micro- and nanoscales through progressive fragmentation. Oceanographic model studies confirm the presence of up to ~2.41 million tons of microplastics across the Atlantic, Pacific, and Indian subtropical gyres. Microplastics distribute from primary (e.g., exfoliating cleansers) and secondary (e.g., chemical deterioration) sources in the environment. This anthropogenic phenomenon poses a threat to the flora and fauna of terrestrial and aquatic ecosystems as ingestion and entanglement cases increase over time. This review focuses on the impact of microplastics across taxa at suggested environmentally relevant concentrations, and advances the groundwork for future ecotoxicological-based research on microplastics …