Biochemistry, Biophysics, and Structural Biology Commons^™

Dual-Mode Tumor Imaging Using Probes That Are Responsive To Hypoxia-Induced Pathological Conditions, S A Amali S Subasinghe, Robia G Pautler, Md Abul Hassan Samee, Jason T Yustein, Matthew J Allen

Faculty, Staff and Students Publications

Hypoxia in solid tumors is associated with poor prognosis, increased aggressiveness, and strong resistance to therapeutics, making accurate monitoring of hypoxia important. Several imaging modalities have been used to study hypoxia, but each modality has inherent limitations. The use of a second modality can compensate for the limitations and validate the results of any single imaging modality. In this review, we describe dual-mode imaging systems for the detection of hypoxia that have been reported since the start of the 21st century. First, we provide a brief overview of the hallmarks of hypoxia used for imaging and the imaging modalities used …

Increasing The Resilience Of Plant Immunity To A Warming Climate, Jong Hum Kim, Christian Castroverde, Shuai Huang, Chao Li, Richard Hilleary, Adam Seroka, Reza Sohrabi, Diana Medina-Yerena, Bethany Huot, Jie Wang, Sharon Marr, Mary Wildermuth, Tao Chen, John Macmicking, Sheng Yang He

Biology Faculty Publications

Extreme weather conditions associated with climate change affect many aspects of plant and animal life, including the response to infectious diseases. Production of salicylic acid (SA), a central plant defence hormone, is particularly vulnerable to suppression by short periods of hot weather above the normal plant growth temperature range via an unknown mechanism. Here we show that suppression of SA production in Arabidopsis thaliana at 28 °C is independent of PHYTOCHROME B (phyB) and EARLY FLOWERING 3 (ELF3), which regulate thermo-responsive plant growth and development. Instead, we found that formation of GUANYLATE BINDING PROTEIN-LIKE 3 (GBPL3) defence-activated biomolecular condensates (GDACs) …

Gain-Of-Signal Assays For Probing Inhibition Of Sars-Cov-2 Mpro/3clpro In Living Cells, Seyed Arad Moghadasi, Morgan A Esler, Yuka Otsuka, Jordan T Becker, Sofia N Moraes, Constance B Anderson, Srinivas Chamakuri, Christopher Belica, Chloe Wick, Daniel A Harki, Damian W Young, Louis Scampavia, Timothy P Spicer, Ke Shi, Hideki Aihara, William L Brown, Reuben S Harris

Faculty, Staff and Students Publications

The main protease, Mpro, of SARS-CoV-2 is required to cleave the viral polyprotein into precise functional units for virus replication and pathogenesis. Here, we report quantitative reporters for Mpro function in living cells in which protease inhibition by genetic or chemical methods results in robust signal readouts by fluorescence (enhanced green fluorescent protein [eGFP]) or bioluminescence (firefly luciferase). These gain-of-signal systems are scalable to high-throughput platforms for quantitative discrimination between Mpro mutants and/or inhibitor potencies as evidenced by validation of several reported inhibitors. Additional utility is shown by single Mpro amino acid variants and structural information combining to demonstrate that …

Crispr/Cas13 Effectors Have Differing Extents Of Off-Target Effects That Limit Their Utility In Eukaryotic Cells, Yuxi Ai, Dongming Liang, Jeremy E Wilusz

Faculty, Staff and Students Publications

CRISPR/Cas13 effectors have garnered increasing attention as easily customizable tools for detecting and depleting RNAs of interest. Near perfect complementarity between a target RNA and the Cas13-associated guide RNA is required for activation of Cas13 ribonuclease activity. Nonetheless, the specificity of Cas13 effectors in eukaryotic cells has been debated as the Cas13 nuclease domains can be exposed on the enzyme surface, providing the potential for promiscuous cleavage of nearby RNAs (so-called collateral damage). Here, using co-transfection assays in Drosophila and human cells, we found that the off-target effects of RxCas13d, a commonly used Cas13 effector, can be as strong as …

Variants In Asph Cause Exertional Heat Illness And Are Associated With Malignant Hyperthermia Susceptibility, Yukari Endo, Linda Groom, Alper Celik, Natalia Kraeva, Chang Seok Lee, Sung Yun Jung, Lois Gardner, Marie-Anne Shaw, Susan L Hamilton, Philip M Hopkins, Robert T Dirksen, Sheila Riazi, James J Dowling

Faculty, Staff and Students Publications

Exertional heat illness (EHI) and malignant hyperthermia (MH) are life threatening conditions associated with muscle breakdown in the setting of triggering factors including volatile anesthetics, exercise, and high environmental temperature. To identify new genetic variants that predispose to EHI and/or MH, we performed genomic sequencing on a cohort with EHI/MH and/or abnormal caffeine-halothane contracture test. In five individuals, we identified rare, pathogenic heterozygous variants in ASPH, a gene encoding junctin, a regulator of excitation-contraction coupling. We validated the pathogenicity of these variants using orthogonal pre-clinical models, CRISPR-edited C2C12 myotubes and transgenic zebrafish. In total, we demonstrate that ASPH variants represent …

Evolutionary Action Of Mutations Reveals Antimicrobial Resistance Genes In Escherichia Coli, David C Marciano, Chen Wang, Teng-Kuei Hsu, Thomas Bourquard, Benu Atri, Ralf B Nehring, Nicholas S Abel, Elizabeth A Bowling, Taylor J Chen, Pamela D Lurie, Panagiotis Katsonis, Susan M Rosenberg, Christophe Herman, Olivier Lichtarge

Faculty, Staff and Students Publications

Since antibiotic development lags, we search for potential drug targets through directed evolution experiments. A challenge is that many resistance genes hide in a noisy mutational background as mutator clones emerge in the adaptive population. Here, to overcome this noise, we quantify the impact of mutations through evolutionary action (EA). After sequencing ciprofloxacin or colistin resistance strains grown under different mutational regimes, we find that an elevated sum of the evolutionary action of mutations in a gene identifies known resistance drivers. This EA integration approach also suggests new antibiotic resistance genes which are then shown to provide a fitness advantage …

Decoding The Pitx2-Controlled Genetic Network In Atrial Fibrillation, Jeffrey D Steimle, Francisco J Grisanti Canozo, Minjun Park, Zachary A Kadow, Md Abul Hassan Samee, James F Martin

Faculty, Staff and Students Publications

Atrial fibrillation (AF), the most common sustained cardiac arrhythmia and a major risk factor for stroke, often arises through ectopic electrical impulses derived from the pulmonary veins (PVs). Sequence variants in enhancers controlling expression of the transcription factor PITX2, which is expressed in the cardiomyocytes (CMs) of the PV and left atrium (LA), have been implicated in AF predisposition. Single nuclei multiomic profiling of RNA and analysis of chromatin accessibility combined with spectral clustering uncovered distinct PV- and LA-enriched CM cell states. Pitx2-mutant PV and LA CMs exhibited gene expression changes consistent with cardiac dysfunction through cell type-distinct, PITX2-directed, cis-regulatory …

College Of Natural Sciences Newsletter, May & June 2022, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 3, Issue 4

Page 1 Dean's Message
Page 2 Awards and Recognition
Page 3-4 The path to a Doctorate Degree
Page 4 American Indian Student Center Native Graduate Honoring Ceremony
Page 5 Celebrating the lives of those who touched the College
Page 6 Media coverage of CNS
Page 7 Open PRAIRIE
Page 8-10 CNS Graduation Festivities
Page 11-14 Spring 2022 Dean's List
Page 16 Richard and Janice Vetter Endowed Professorship in Biotechnology.position

Optimization Of Palmitic Acid Production In Chloroidium Sp. Utex 3007 As A Sustainable Source Of Palm Oil Alternative, Amnah Salem Alzahmi

Theses

The increase in palm oil consumption and production has resulted in removing up to 90% of trees in some tropical forests. The green microalgae Chloroidium sp. UTEX 3007 can be an alternative sustainable source of palm oil due to its high palmitic acid content. The objective of this study was to generate a mutant Chloroidium population that is capable of producing and accumulating elevated levels of palmitic acid and to characterize the obtained populations’ lipid contents. The palmitic acid production optimization in Chloroidium sp. UTEX 3007 was conducted via a workflow of ultraviolet (UV) mutagenesis and sorting of high-lipid producing …

Syphilis In The Esophagus, Ronan Allencherril, Paul Nicholls, Shilpa Jain, Robert Sealock, Priti Dangayach

Faculty, Staff and Students Publications

This report documents a unique case of syphilis with esophageal involvement. Such a presentation is exceedingly rare in the modern era, particularly among patients without human immunodeficiency virus. Most instances were documented in the 1900s and earlier. Our patient presented with months of odynophagia and recurrent oral lesions. He was found to have a sizeable esophageal ulcer on endoscopy, with biopsy confirming the diagnosis of syphilis. His symptoms quickly resolved with intramuscular penicillin. This case highlights the importance of keeping a broad differential for odynophagia and suspicious lesions, cutaneous or mucosal.

A Novel Crosstalk Between Autophagosomes And Phagosomes That Facilitates The Clearance Of Apoptotic Cells, Zheng Zhou, Omar Peña-Ramos

Faculty, Staff and Students Publications

During an animal's life, many cells undergo apoptosis, a form of genetically programmed cell death. These cells are swiftly engulfed by other cells through phagocytosis and subsequently degraded inside phagosomes. Phagocytosis and macroautophagy/autophagy are two different cellular events: whereas phagocytosis is a cell-eat-cell event, autophagy, or "self-eating", occurs within one cell, resulting in the enveloping of protein aggregates or damaged organelles within double-membrane autophagosomes. Despite this critical difference, these two events share common features: (1) both are means of safe garbage disposal; (2) both phagosomes and autophagosomes fuse to lysosomes, which drive the degradation of their contents; and (3) both …

Bodipy-Based Light-Responsive Materials, Zhaoxiong Wan

Dissertations

The energy required for life on our planet is provided by light. In science, light is an important and powerful tool for measuring and modifying substances. For example, under the effect of illumination, light-responsive materials can change their physical and chemical properties. Photochemistry is a branch of research to study the effects of light irradiation on chemical structures and reactions. Some photochemical changes could lead to chemical bond dissociation (such as in photosynthesis) and structure isomerization (such as in the retina). Photochemistry has a strong relationship with human lives and it is essential in many ways. Among photophysics, fluorescence emission …

The Effects Of Aging On Wound Healing And Limb Regeneration In The Axolotl, Hande Sahin

Graduate Masters Theses

The Mexican axolotl is capable of regenerating various parts of its body and maintains this capacity throughout its entire life. Although this ability is sustained through adulthood, multiple regenerative processes appear to be negatively affected by aging. Here, we focus on evaluating the effect of aging on the rate of wound healing and limb regeneration. We have developed new in vivo, and ex vivo assays to characterize wound healing and identify differences between young and aged animals during this process. We have also characterized morphological features of mature skin from both groups of animals and although there are no obvious …

A Concise Synthetic Method For Constructing 3-Substituted Piperazine-2-Acetic Acid Esters From 1,2-Diamines, Srinivas Chamakuri, Sunny Ann Tang, Kevin A Tran, Shiva Krishna Reddy Guduru, Peter K Bolin, Kevin R Mackenzie, Damian W Young

Faculty, Staff and Students Publications

We report a short synthetic route for synthesizing 2,3-substituted piperazine acetic acid esters. Optically pure amino acids were efficiently converted into 1,2-diamines that could be utilized to deliver the title 2,3-substituted piperazines in five steps with a high enantiomeric purity. The novel route facilitated, for the first time, the synthesis of 3-phenyl substituted-2-piperazine acetic acid esters that were difficult to achieve using other methods; however, in this case, the products underwent racemization.

Maf1, A Repressor Of Rna Polymerase Iii-Dependent Transcription, Regulates Bone Mass, Ellen Phillips, Naseer Ahmad, Li Sun, James Iben, Christopher J Walkey, Aleksandra Rusin, Tony Yuen, Clifford J Rosen, Ian M Willis, Mone Zaidi, Deborah L Johnson

Faculty, Staff and Students Publications

MAF1, a key repressor of RNA polymerase (pol) III-mediated transcription, has been shown to promote mesoderm formation in vitro. Here, we show that MAF1 plays a critical role in regulating osteoblast differentiation and bone mass. Global deletion of MAF1 (Maf1-/- mice) produced a high bone mass phenotype. However, osteoblasts isolated from Maf1-/- mice showed reduced osteoblastogenesis ex vivo. Therefore, we determined the phenotype of mice overexpressing MAF1 in cells from the mesenchymal lineage (Prx1-Cre;LSL-MAF1 mice). These mice showed increased bone mass. Ex vivo, cells from these mice showed enhanced osteoblastogenesis concordant with their high …

Targeting Aberrant Replication And Dna Repair Events For Treating Breast Cancers, Subapriya Rajamanickam, Jun Hyoung Park, Panneerdoss Subbarayalu, Santosh Timilsina, Kaitlyn Bates, Pooja Yadav, Saif S R Nirzhor, Vijay Eedunuri, Tabrez A Mohammad, Kwang Hwa Jung, Benjamin Onyeagucha, Nourhan Abdelfattah, Raymond Benevides, Grace Lee, Yidong Chen, Ratna Vadlamudi, Andrew Brenner, Virginia Kaklamani, Ismail Jatoi, John Kuhn, Robert Hromas, Yogesh K Gupta, Benny A Kaipparettu, Jack L Arbiser, Manjeet K Rao

Faculty, Staff and Students Publications

The major limitations of DNA-targeting chemotherapy drugs include life-threatening toxicity, acquired resistance and occurrence of secondary cancers. Here, we report a small molecule, Carbazole Blue (CB), that binds to DNA and inhibits cancer growth and metastasis by targeting DNA-related processes that tumor cells use but not the normal cells. We show that CB inhibits the expression of pro-tumorigenic genes that promote unchecked replication and aberrant DNA repair that cancer cells get addicted to survive. In contrast to chemotherapy drugs, systemic delivery of CB suppressed breast cancer growth and metastasis with no toxicity in pre-clinical mouse models. Using PDX and ex …

Alterations Of The Gut Microbial Community Structure And Function With Aging In The Spontaneously Hypertensive Stroke Prone Rat, Huanan Shi, James W Nelson, Sharon Phillips, Joseph F Petrosino, Robert M Bryan, David J Durgan

Faculty, Staff and Students Publications

Gut dysbiosis, a pathological imbalance of bacteria, has been shown to contribute to the development of hypertension (HT), systemic- and neuro-inflammation, and blood-brain barrier (BBB) disruption in spontaneously hypertensive stroke prone rats (SHRSP). However, to date individual species that contribute to HT in the SHRSP model have not been identified. One potential reason, is that nearly all studies of the SHRSP gut microbiota have analyzed samples from rats with established HT. The goal of this study was to examine the SHRSP gut microbiota before, during, and after the onset of hypertension, and in normotensive WKY control rats over the same …

Du Undergraduate Showcase: Research, Scholarship, And Creative Works: Abstracts, Emma Aggeler, Elena Arroway, Daisy T. Booker, Justin Bravo, Kyle Bucholtz, Megan Burnham, Nicole Choi, Spencer Cockerell, Rosie Contino, Jackson Garske, Kaitlyn Glover, Caroline Hamilton, Haley Hartmann, Madalyne Heiken, Colin Holter, Leah Huzjak, Alyssa Jeng, Cole Jernigan, Chad Kashiwa, Adelaide Kerenick, Emily King, Abigail Langeberg, Maddie Leake, Meredith Lemons, Alec Mackay, Greer Mckinley, Ori Miller, Guy Milliman, Katherine Miromonti, Audrey Mitchell, Lauren Moak, Megan Morrell, Gelella Nebiyu, Zdenek Otruba, Toni V. Panzera, Kassidy Patarino, Sneha Patil, Alexandra Penney, Kevin Persky, Caitlin Pham, Gabriela Recinos, Mary Ringgenberg, Chase Routt, Olivia Schneider, Roman Shrestha, Arlo Simmerman, Alec Smith, Tessa Smith, Nhi-Lac Thai, Kyle Thurmann, Casey Tindall, Amelia Trembath, Maria Trubetskaya, Zachary Vangelisti, Peter Vo, Abby Walker, David Winter, Grayden Wolfe, Leah York

DU Undergraduate Research Journal Archive

Abstracts from the DU Undergraduate Showcase.

A Review Of Current Methods In Avian Dietary Analysis And Their Integrated Application To Characterize The Trophic Niche Of Louisiana Waterthrush (Parkesia Motacilla)., Brandon Hoenig

Electronic Theses and Dissertations

Characterizing a species’ dietary composition presents an avenue to understand many facets of its ecological niche and can provide essential information for the species’ long-term conservation. To date, the vast majority of diet studies have relied on direct identification of prey during foraging observations or from diet samples to characterize the dietary habits of birds. However, advancements in laboratory-based approaches have revolutionized the field of trophic ecology by allowing researchers to indirectly infer dietary habits with higher resolution across greater time scales. Here, I apply two of these laboratory-based techniques, namely DNA metabarcoding and stable isotope analysis, to characterize the …

Determining The Distribution Of Elemental Compounds And Oxidative Potential Across Fine Particulate Matter (Pm2.5) Filters, Allie Michelle Sidwell

Honors Theses

Fine particulate matter (PM_2.5) is a complex mixture of particles and sorbed chemicals that poses serious, adverse effects on human health such as increasing cardiovascular and respiratory morbidity and mortality. There is ongoing research into the impacts of PM_2.5 of differing chemical compositions, sampling location, and the mechanisms for the observed health effects. To conduct these analytical and toxicology studies of PM_2.5, researchers often split filters into sections. This process allows multiple, often destructive, assays to be performed. Our previous research showed chemical composition differences across PM_2.5 filters. The goal of our study was …

Development And Analysis Of Next-Generation Polymeric And Bio-Ceramic Based Orthopedic Scaffolds By Advanced Manufacturing Techniques, Sudeep K. Gummadi

ETD Archive

Gliomas express mutant isocitrate dehydrogenases producing excessive amounts of D 2-hydroxyglutarate (D2HG) and releasing some of it into the environment. The immune surveillance is reduced as a result, however, the mechanisms behind lymphocyte suppression by the D2HG stereoisomer remain unknown. I incubated Jurkat T cells with D2HG at concentrations present within and surrounding gliomas, or its obverse L2HG stereoisomer, and quantified 2HG isomers within washed cells by TSPC derivatization with stable isotope-labeled D2HG and L2HG internal standards, HPLC separation, and mass spectrometry. D2HG was found in quiescent cells in double the amount of L2HG. External D2HG or L2HG increased the …

Evaluation Of Diaphragmatic Movement In The Respiratory System Of An Emphysema Patient, Aubri Ford

Honor’s College Freeman Research Journal

Respiration is an essential part of life. The diaphragm is the main muscle involved in the process of respiration. However, respiratory diseases such as emphysema alter the function of the diaphragm which sometimes leads to respiratory failure and death. This review compiles studies concerning emphysema and how the morphological changes in the lungs (i.e. hyperinflation) caused by the disease affect the diaphragm. The first major point covers the risks associated with developing the disease as a component of Chronic Obstructive Pulmonary Disease (COPD). Next, the paper outlines the pathophysiology of emphysema within the lungs, the methods used to diagnose emphysema, …

Spike Protein Structural Dynamics Of Sars-Cov-2 Coronaviruses Studied Using Molecular Dynamics, William Strickland

Biological Sciences Undergraduate Honors Theses

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has overwhelmingly impacted the global population, accounting for millions of confirmed infections and deaths over the last year. The virus’s influence on the health and safety of individuals, the economy, and daily life has been disruptive and devastating. While SARS-CoV-2 and SARS-CoV-1, two closely related members of the SARS coronaviruses, have shown the ability to cross the species barrier and infect humans, SARS-CoV-2 has predominantly been the virus responsible for the number of infections presently known. SARS-CoV-2 has also proven to be volatile, as many variants have …

Nanotechnology-Based Approaches To Mitigate Environmental Pollutants -- Induced Neurological Disorders, Jyoti Ahlawat

Open Access Theses & Dissertations

Neurodegenerative diseases such as Parkinson's disease (PD), Alzheimerâ??s Disease (AD) and Huntingtonâ??s Disease (HD) have no cure despite intensive research efforts geared towards therapeutics development. In the USA, patients with PD and AD alone cost the nation ~ $200 billion annually in patient care and lost productivity. Therefore, there remains an urgent and unmet need to develop novel drugs and drug carriers with the potential to slow down, halt and ideally reverse the course of neurodegenerative disorders. The dissertation focuses on developing approaches towards targeting PD using multifactorial mechanisms including the targeting of protein aggregation and oxidative stress. This is …

Characterization Of Fgf1/Fgf2 Heterodimer With Mutation R136e, Brett Haley

Biological Sciences Undergraduate Honors Theses

Fibroblast growth factors are a family of heparin binding proteins that are involved in a broad spectrum of physiological functions, such as angiogenesis, cell proliferation, cell differentiation, and wound healing. Fibroblast growth factor 1 (FGF-1) is a member of the FGF superfamily and can bind universally to fibroblast growth factor receptors. Fibroblast growth factor 2 (FGF-2) is similar in structure to FGF-1 but has been shown to have a potent effect on angiogenesis. A physiologically stable dimerization of these two growth factors could prove to induce desirable effects in the instance of wound healing. In this study, we have designed …

Regulation Of The Reaction Between Cytochrome C And Cytochrome C Oxidase In The Mitochondria, Anders Nowell

Biological Sciences Undergraduate Honors Theses

Cytochrome c (Cc) is a multifunction protein that has important life and death functions in the cell. In the electron transport chain (ETC), Cc transfers electrons from cytochrome bc₁ to cytochrome c oxidase (CcO), which helps build the electrochemical gradient that drives ATP synthase. The reaction of Cc with CcO is very important in ETC regulatory processes. Previous research shows phosphorylation sites in Cc that affect the binding with CcO, with measurable effects on k_d, k_f, and K_D. These effects result in changes in mitochondrial membrane potentials, respiration, and reactive oxygen species (ROS) …

Contemporary Biomarker Strategies For Patients With Chest Pain, Stephen Boone, W Frank Peacock

Faculty, Staff and Students Publications

This review focuses on the strengths and limitations of conventional and high-sensitivity troponin in the evaluation of patients with suspected acute coronary syndromes. High-sensitivity troponin (hsTn) assays represent a significant innovation over prior generation troponin assays. Owing to superior analytical precision, hsTn permits more rapid "rule-in" and "rule-out" of myocardial infarction. Furthermore, hsTn assays, in properly implemented clinical pathways, permit a reduction in the portion of patients requiring extended observation and testing.

Modulation Of Kras Structure And Dynamics By Kras Ubiquitination And Membrane Depolarization, Vinay Nair

Dissertations and Theses (Open Access)

KRAS, a 21 kDa small GTPase protein, functions as a molecular switch playing a key role in regulating cell proliferation. Dysregulation of KRAS signaling by oncogenic mutations leads to uncontrolled cell proliferation, a hallmark of cancer cells. Attempts to therapeutically target oncogenic KRAS have led to limited success resulting in a need to identify new mechanisms to targeting KRAS. The interaction of KRAS with its regulators, effectors, and the membrane present one such avenue. In this study, we investigated how post-translational covalent and environmental modifications could modulate these interactions of KRAS. Using computational molecular dynamics simulations, nuclear magnetic resonance spectroscopy …

Supertertiary Structural Dynamics Modulate Function In Postsynaptic Density Protein 95, George L. Hamilton Iii

All Dissertations

Proteins, RNA, and DNA serve as the primary sub-cellular machinery that give rise to the necessary functions of life. The long-standing paradigm has been that the structures of biomolecules, or the arrangement of the subunits that make up a biomolecule, determine biological function. However, biomolecules are not static objects. Instead, they often undergo structural rearrangements that are crucial to enabling and regulating their functions. In my thesis I present several studies of the interplay between the structures, dynamics, and functions of biomolecules that combine experimental fluorescence spectroscopy and computational methods to probe these systems at the single-molecule level. In particular, …

Time Course Investigation Of The Dermal Leukocyte Response To Lipoteichoic Acid In Chickens, Ian Gilbert

Animal Science Undergraduate Honors Theses

Lipoteichoic acid (LTA) is component of the cell wall of Gram-positive bacteria that stimulates inflammation during bacterial infection. However, few studies have investigated the in vivo immune response to LTA, and none of the in vivo studies done have been performed in birds. For this project, the pulp (a skin-derivative) of growing feathers (GFs) of chickens were used as a test site to investigate the in vivo effects of intradermally injected LTA. In Study 1, the pulp of 12 GFs of 11-week-old Light-brown Leghorn (LBL) males were injected with 10 μL of differing concentrations of LTA (0.1, 1.0, 10, 100 …