Digital Commons Network^™

United States National Science Foundation Response To The Office Of Science And Technology Policy Memo, 2022: Public Access Plan (February 2023)

Copyright, Fair Use, Scholarly Communication, etc.

NSF response to OSTP memo, 2022: Public Access Plan (February 2023)

The Impact Of Covid-19 And Associated Policy Responses On Global Food Security, Edward J. Balistreri, Felix Baquedano, John C. Beghin

Department of Economics: Faculty Publications

We analyze the impact of the COVID-19 pandemic and associated policy responses on the global economy and food security in 80 low- and middle-income countries. We use a global economy-wide model with detailed disaggregation of agricultural and food sectors and develop a business-as-usual baseline for 2020 and 2021 called “But-for-COVID” (BfC). We then shock the model with aggregate income shocks derived from the IMF World Economic Outlook for 2020 and 2021. We impose total-factor productivity losses in key sectors as well as consumption decreases induced by social distancing. The resulting shocks in prices and incomes from the CGE model simulations …

A Framework To Predict Variability Characteristics In Building Load Profiles, Sam Moayedi, Andrew Parker, Kevin James, Xiaoyue Cheng, Michael Hempel, Hamid Sharif, Mahmoud A. Alahmad

Durham School of Architectural Engineering and Construction: Faculty Publications

The expansion of Advanced Metering Infrastructure (AMI) has provided building operators and researchers detailed information on building energy consumption. The majority of AMI systems, however, record data at relatively low resolutions of 15, 30, or 60 minutes, due to cost, storage and bandwidth limitations. Emerging applications in power flow analysis, Quasi-Static Time-Series Simulation (QSTS), smart grid integration and load matching, however, require data at higher resolutions. Short-term energy demand can deviate significantly from long-term averages, with an unknown magnitude and frequency when only low-resolution load profile data is available. This paper presents a novel data-driven approach to predict characteristics of …

Displaying And Delivering Viral Membrane Antigens Via Ww Domain–Activated Extracellular Vesicles, Sengjin Choi, Zhiping Yang, Qiyu Wang, Zhi Qiao, Maoyun Sun, Joshua Wiggins, Shi-Hua Xiang, Quan Lu

Nebraska Center for Virology: Faculty Publications

Membrane proteins expressed on the surface of enveloped viruses are conformational antigens readily recognized by B cells of the immune system. An effective vaccine would require the synthesis and delivery of these native conformational antigens in lipid membranes that preserve specific epitope structures. We have created an extracellular vesicle–based technology that allows viral membrane antigens to be selectively recruited onto the surface of WW domain–activated extracellular vesicles (WAEVs). Budding of WAEVs requires secretory carrier-associated membrane protein 3, which through its proline-proline-alanine-tyrosine motif interacts with WW domains to recruit fused viral membrane antigens onto WAEVs. Immunization with influenza and HIV viral …

Displaying And Delivering Viral Membrane Antigens Via Ww Domain–Activated Extracellular Vesicles, Sengjin Choi, Zhiping Yang, Qiyu Wang, Zhi Qiao, Maoyun Sun, Joshua Wiggins, Shi-Hua Xiang, Quan Lu

Nebraska Center for Virology: Faculty Publications

Membrane proteins expressed on the surface of enveloped viruses are conformational antigens readily recognized by B cells of the immune system. An effective vaccine would require the synthesis and delivery of these native conformational antigens in lipid membranes that preserve specific epitope structures. We have created an extracellular vesicle–based technology that allows viral membrane antigens to be selectively recruited onto the surface of WW domain–activated extracellular vesicles (WAEVs). Budding of WAEVs requires secretory carrier-associated membrane protein 3, which through its proline-proline-alanine-tyrosine motif interacts with WW domains to recruit fused viral membrane antigens onto WAEVs. Immunization with influenza and HIV viral …

Displaying And Delivering Viral Membrane Antigens Via Ww Domain–Activated Extracellular Vesicles, Sengjin Choi, Zhiping Yang, Qiyu Wang, Zhi Qiao, Maoyun Sun, Joshua Wiggins, Shi-Hua Xiang, Quan Lu

School of Veterinary and Biomedical Sciences: Faculty Publications

Membrane proteins expressed on the surface of enveloped viruses are conformational antigens readily recognized by B cells of the immune system. An effective vaccine would require the synthesis and delivery of these native conformational antigens in lipid membranes that preserve specific epitope structures. We have created an extracellular vesicle–based technology that allows viral membrane antigens to be selectively recruited onto the surface of WW domain–activated extracellular vesicles (WAEVs). Budding of WAEVs requires secretory carrier-associated membrane protein 3, which through its proline-proline-alanine-tyrosine motif interacts with WW domains to recruit fused viral membrane antigens onto WAEVs. Immunization with influenza and HIV viral …

Vaccines Against Group B Coxsackieviruses And Their Importance, Kiruthiga Mone, Ninaad Lasrado, Meghna Sur, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

The group B coxsackieviruses (CVBs) exist in six serotypes (CVB1 to CVB6). Disease associations have been reported for most serotypes, and multiple serotypes can cause similar diseases. For example, CVB1, CVB3, and CVB5 are generally implicated in the causation of myocarditis, whereas CVB1 and CVB4 could accelerate the development of type 1 diabetes (T1D). Yet, no vaccines against these viruses are currently available. In this review, we have analyzed the attributes of experimentally tested vaccines and discussed their merits and demerits or limitations, as well as their impact in preventing infections, most importantly myocarditis and T1D.

Coupling Nitrate Capture With Ammonia Production Through Bifunctional Redox-Electrodes, Kwiyong Kim, Alexandra Zagalskaya, Jing Lian Ng, Jaeyoung Hong, Vitaly Alexandrov, Tuan Anh Pham, Xiao Su

Department of Chemical and Biomolecular Engineering: Faculty Publications

Nitrate is a ubiquitous aqueous pollutant from agricultural and industrial activities. At the same time, conversion of nitrate to ammonia provides an attractive solution for the coupled environmental and energy challenge underlying the nitrogen cycle, by valorizing a pollutant to a carbon-free energy carrier and essential chemical feedstock. Mass transport limitations are a key obstacle to the efficient conversion of nitrate to ammonia from water streams, due to the dilute concentration of nitrate. Here, we develop bifunctional electrodes that couple a nitrate-selective redox-electrosorbent (polyaniline) with an electrocatalyst (cobalt oxide) for nitrate to ammonium conversion. We demonstrate the synergistic reactive separation …

Evaluation Of Pollination Traits Important For Hybrid Wheat Development In Great Plains Germplasm, Nicholas Garst, Vikas Belamkar, Amanda Easterly, Mary J. Guttieri, Hannah Stoll, Amir M. H. Ibrahim, P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Hybrid wheat (Triticum aestivumL.) offers potential yield advantages over conventional inbred cultivars. For hybrid wheat to be a commercial success, the cost to produce the hybrid seed needs to be minimized. Although wheat is naturally selfpollinated, hybrid wheat seed production can be improved by increasing the amount and availability of pollen for cross-pollination. This research examined 19 pollination traits using the Hard Winter Wheat Association Mapping Panel for 3 years. Anther extrusion, pollen 50 date (date at which a genotype has 50% of spikes pollinating), plant height, and pollination duration (last spike pollen 50 date minus first spike …

Depletion Of Hiv Reservoir By Activation Of Isr Signaling In Resting Cd4+T Cells, Dajiang Li, Lilly M. Wong, Yuyang Tang, Brigitte Allard, Katherine S. James, George R. Thompson, Satya Dandekar, Edward P. Browne, Qingsheng Li, Jeremy M. Simon, Nancie M. Archin, David M. Margolis, Guochun Jiang

School of Biological Sciences: Faculty Publications

HIV reservoirs are extremely stable and pose a tremendous challenge to clear HIV infection. Here, we demonstrate that activation of ISR/ATF4 signaling reverses HIV latency, which also selectively eliminates HIV+ cells in primary CD4⁺T cell model of latency without effect on HIV-negative CD⁴⁺T cells. The reduction of HIV+ cells is associated with apoptosis enhancement, but surprisingly is largely seen in HIV-infected cells in which gag-pol RNA transcripts are detected in HIV RNA-induced ATF4/IFIT signaling. In resting CD4⁺ (rCD4⁺) T cells isolated from people living with HIV on antiretroviral therapy, induction of ISR/ATF4 signaling …

Personalized Matched Targeted Therapy In Advanced Pancreatic Cancer: A Pilot Cohort Analysis, Justin Shaya, Shumei Kato, Jacob J. Adashek, Hitendra Patel, Paul T. Fanta, Gregory P. Botta, Jason K. Sicklick, Razelle Kurzrock

School of Veterinary and Biomedical Sciences: Faculty Publications

Despite progress, 2-year pancreatic cancer survival remains dismal. We evaluated a biomarker-driven, combination/N-of-one strategy in 18 patients (advanced/metastatic pancreatic cancer) (from Molecular Tumor Board). Targeted agents administered/ patient = 2.5 (median) (range, 1–4); first-line therapy (N = 5); second line, (N = 13). Comparing patients (high versus low degrees of matching) (matching score ≥50% versus <50%; reflecting number of alterations matched to targeted agents divided by number of pathogenic alterations), survival was significantly longer (hazard ratio [HR] 0.24 (95% confidence interval [CI], 0.078–0.76, P = 0.016); clinical benefit rates (CBR) (stable disease ≥6 months/partial/complete response) trended higher (45.5 vs 0.0%, P = 0.10); progression-free survival, HR, 95% CI, 0.36 (0.12–1.10) (p = 0.075). First versus ≥2nd-line therapy had higher CBRs (80.0 vs 7.7%, P = …

Co-Culture Models Of Endothelial Cells, Macrophages, And Vascular Smooth Muscle Cells For The Study Of The Natural History Of Atherosclerosis, Martin Liu, Saurabhi Samant, Charu Hasini Vasa, Ryan M. Pedrigi, Usama Oguz, Sangjin Ryu, Timothy Wei, Daniel R. Anderson, Devandra K. Agrawal, Yiannis Chatzizisis

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Background

This work aims to present a fast, affordable, and reproducible three-cell co-culture system that could represent the different cellular mechanisms of atherosclerosis, extending from atherogenesis to pathological intimal thickening.

Methods and results

We built four culture models: (i) Culture model #1 (representing normal arterial intima), where human coronary artery endothelial cells were added on top of Matrigel-coated collagen type I matrix, (ii) Culture model #2 (representing atherogenesis), which demonstrated the subendothelial accumulation and oxidative modification of low-density lipoproteins (LDL), (iii) Culture model #3 (representing intimal xanthomas), which demonstrated the monocyte adhesion to the endothelial cell monolayer, transmigration into the …

The Federalists Of The Internet? What Online Platforms Can Learn From Reddit’S Decentralized Content Moderation Scheme, Vincent Marrazzo

Nebraska Law Bulletin (Selected Issues)

As online platforms become the primary carriers of news and information in society, their content moderation policies will have increasing power over users’ daily lives. Centralized moderation is inappropriate and inefficient because it forces all online communities to adhere to the same (and often arbitrary) standards. Decentralized moderation, however, allows most moderation decisions to be made by users who are intimately aware of the contours of individual online communities. Such decisions are less likely to restrict content that is not violative of an online communities’ standards.

This concept of subsidiarity mirrors the arguments made in favor of federalism in which …

Seasonal Plasticity In Morphology And Metabolism Differs Between Migratory North American And Resident Costa Rican Monarch Butterflies, Ayşe Tenger-Trolander, Cole R. Julick, Wei Lu, Delbert André Green, Kristi L. Montooth, Marcus R. Kronforst

School of Biological Sciences: Faculty Publications

Environmental heterogeneity in temperate latitudes is expected to maintain seasonally plastic life-history strategies that include the tuning of morphologies and metabolism that support overwintering. For species that have expanded their ranges into tropical latitudes, it is unclear the extent to which the capacity for plasticity will be maintained or will erode with disuse. The migratory generations of the North American (NA) monarch butterfly Danaus plexippus lead distinctly different lives from their summer generation NA parents and their tropical descendants living in Costa Rica (CR). NA migratory monarchs postpone reproduction, travel thousands of kilometers south to overwinter in Mexico, and subsist …

Application Of Neural Networks For Hydrologic Process Understanding At A Midwestern Watershed, Annushka Aliev, Sinan Rasiya Koya, Incheol Kim, Jongwan Eun, Elbert Traylor, Tirthankar Roy

Department of Civil and Environmental Engineering: Faculty Publications

The Shell Creek Watershed (SCW) is a rural watershed in Nebraska with a history of chronic flooding. Beginning in 2005, a variety of conservation practices have been employed in the watershed. Those practices have since been credited with attenuating flood severity and improving water quality in SCW. This study investigated the impacts of 13 different controlling factors on flooding at SCW by using an artificial neural network (ANN)-based rainfall-runoff model. Additionally, flood frequency analysis and drought severity analysis were conducted. Special emphasis was placed on understanding how flood trends change in light of conservation practices to determine whether any relation …

Does Preschool Executive Control Mediate The Impact Of Early Environmental Unpredictability And Deprivation On The General Factor Of Psychopathology A Decade Later?, Eric Phillips, Rebecca L. Brock, Tiffany D. James, Jennifer Nelson, W. Alex Mason, Kimberly Andrews Espy, Timothy D. Nelson

Department of Psychology: Faculty Publications

Background: Although deprivation has been consistently shown to increase risk for psychopathology through impaired executive control, the unique effects of other dimensions of early adversity, such as unpredictability, on executive control development are poorly understood. The current study evaluated whether deprivation and/or unpredictability early in life have unique effects on the general factor of psychopathology through impaired preschool executive control. Methods: Participants included 312 children (51% female) oversampled for greater sociodemographic risk. Preschool executive control was measured using a battery of nine developmentally appropriate executive control tasks. Dimensions of adversity were measured with observational and caregiver assessments, and …

Long-Term Manure Application Improves Soil Health And Stabilizes Carbon In Continuous Maize Production System, Saurav Das, Daniel Liptzin, Bijesh Maharjan

Department of Agronomy and Horticulture: Faculty Publications

Soil health lies at the core of a sustainable food production system. A comprehensive evaluation of different agronomic practices and their effect on soil health is essential to determine the best practices that support soil ecosystem services. However, it may take years or decades to observe measurable changes in soil health under varying management practices. The objective of this experiment was to evaluate the effects of long-term (>77 years) manure and inorganic nitrogen (N) fertilizer on soil health and determine the interrelationship among the measured soil bio-physicochemical indicators. The study also aims to understand the sustainability of the monocropping …

A Draft Diabrotica Virgifera Virgifera Genome: Insights Into Control And Host Plant Adaption By A Major Maize Pest Insect, Brad S. Coates, Kimberly K. O. Walden, Dimpal Lata, Neetha Nanoth Vellichirammal, Robert F. Mitchell, Martin N. Andersson, Rachel Mckay, Marcé D. Lorenzen, Nathaniel Grubbs, Yu‑Hui Wang, Jinlong Han, Jing Li Xuan, Peter Willadsen, Huichun Wang, B. Wade French, Raman Bansal, Sammy Sedky, Dariane Souza, Dakota Bunn, Lance J. Meinke, Nicholas J. Miller, Blair D. Siegfried11,, Thomas W. Sappington, Hugh M. Robertson

Department of Entomology: Faculty Publications

Background Adaptations by arthropod pests to host plant defenses of crops determine their impacts on agricultural production. The larval host range of western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), is restricted to maize and a few grasses. Resistance of D. v. virgifera to crop rotation practices and multiple insecticides contributes to its status as the most damaging pest of cultivated maize in North America and Europe. The extent to which adaptations by this pest contributes to host plant specialization remains unknown.

Results A 2.42 Gb draft D. v. virgifera genome, Dvir_v2.0, was assembled from short shotgun reads and scaffolded …

Simulated Impacts Of Winter Rye Cover Crop On Continuous Corn Yield And Soil Parameters, Girma Birr, Andualem S. Shiferaw, Tsegaye Tadesse, Marty R. Schmer, Virginia L. Jin, Brian D. Wardlow, Katja Koehler-Cole, Tala Awada, Sarah Beebout, Teferi Tsegaye, Tulsi Kahrel

Department of Agronomy and Horticulture: Faculty Publications

Cover crops (CC) provide numerous ecosystem services such as improving soil health, reducing nutrient loss, increasing productivity, and mitigating greenhouse gas emission. However, adoption of CC has been hindered by perceived negative impacts on main crop productivity and additional production costs. This is partly attributed to the gap in current state of knowledge in CC and its interaction with main crop production under different biophysical conditions. In this study, Decision Support System for Agrotechnology Transfer model was used to evaluate the long-term impact of cereal rye (Secale cereale L.) on corn (Zea mays L.) yield, soil organic carbon …

Extending The Breadth Of Saliva Metabolome Fngerprinting By Smart Template Strategies And Efective Pattern Realignment On Comprehensive Two‑Dimensional Gas Chromatographic Data, Simone Squara, Friederike Manig, Thomas Henle, Michael Hellwig, Andrea Caratti, Carlo Bicchi, Stephen E. Reichenbach, Qingping Tao, Massimo Collino, Chiara Cordero

School of Computing: Faculty Publications

Comprehensive two-dimensional gas chromatography with time-of-fight mass spectrometry (GC×GC-TOFMS) is one the most powerful analytical platforms for chemical investigations of complex biological samples. It produces large datasets that are rich in information, but highly complex, and its consistency may be affected by random systemic fluctuations and/ or changes in the experimental parameters. This study details the optimization of a data processing strategy that compensates for severe 2D pattern misalignments and detector response fluctuations for saliva samples analyzed across 2 years. The strategy was trained on two batches: one with samples from healthy subjects who had undergone dietary intervention with high/low-Maillard …

Type Ii Taste Cells Participate In Mucosal Immune Surveillance, Yumei Qin, Salin Raj Palayyan, Xin Zheng, Shiyi Tian, Robert F. Margolskee, Sunil Kumar Sukumaran

Department of Nutrition and Health Sciences: Faculty Publications

The oral microbiome is second only to its intestinal counterpart in diversity and abundance but its effects on taste cells remains largely unexplored. Using single-cell RNASeq, we found that mouse taste cells, in particular, sweet and umami receptor cells that express taste 1 receptor member 3 (Tas1r3), have a gene expression signature reminiscent of Microfold (M) cells, a central player in immune surveillance in the mucosa-associated lymphoid tissue (MALT) such as those in the Peyer’s patch and tonsils. Administration of tumor necrosis factor ligand superfamily member 11 (TNFSF11; also known as RANKL), a growth factor required for differentiation …

“The Drug Sellerswere Better Organized Than The Government”: A Qualitative Study Of Participants’ Views Of Drug Markets During Covid-19 And Other Big Events, Roberto Abadie

School of Global Integrative Studies: Faculty Publications

“Big events”, such as wars, economic crises, pandemics, or natural disasters, affect the risk environment in which people use drugs. While the impact of big events on injection risk behaviors and access to drug-treatment services is well documented, less is known about the effects of big events on drug markets. Based on self-reporting data on drug availability among people who use drugs (PWUD) in the aftermath of Hurricane Maria in Puerto Rico and during the COVID- 19 lockdown in a Midwestern US state, this study aims to document the effects of big events on drug markets. Qualitative data on the …

Evaluation Of Precision Livestock Technology And Human Scoring Of Nursery Pigs In A Controlled Immune Challenge Experiment, Eduarda M. Bortoluzzi, Mikayla J. Goering, Sara J. Ochoa, Aaron J. Holliday, Jared M. Mumm, Catherine E. Nelson, Hui Wu, Benny E. Mote, Eric T. Psota, Ty B. Schmidt, Majid Jaberi-Douraki, Lindsey E. Hulbert

Department of Animal Science: Faculty Publications

The objectives were to determine the sensitivity, specificity, and cutoff values of a visual-based precision livestock technology (NUtrack), and determine the sensitivity and specificity of sickness score data collected with the live observation by trained human observers. At weaning, pigs (n = 192; gilts and barrows) were randomly assigned to one of twelve pens (16/pen) and treatments were randomly assigned to pens. Sham-pen pigs all received subcutaneous saline (3 mL). For LPS-pen pigs, all pigs received subcutaneous lipopolysaccharide (LPS; 300 µg/kg BW; E. coli O111:B4; in 3 mL of saline). For the last treatment, eight pigs were randomly …

Evaluation Of Precision Livestock Technology And Human Scoring Of Nursery Pigs In A Controlled Immune Challenge Experiment, Eduarda M. Bortoluzzi, Mikayla J. Goering, Sara J. Ochoa, Aaron J. Holliday, Jared M. Mumm, Catherine E. Nelson, Hui Wu, Benny Mote, Eric T. Psota, Ty B. Schmidt, Majid Jaberi-Douraki, Lindsey E. Hulbert

Department of Animal Science: Faculty Publications

The objectives were to determine the sensitivity, specificity, and cutoff values of a visual-based precision livestock technology (NUtrack), and determine the sensitivity and specificity of sickness score data collected with the live observation by trained human observers. At weaning, pigs (n = 192; gilts and barrows) were randomly assigned to one of twelve pens (16/pen) and treatments were randomly assigned to pens. Sham-pen pigs all received subcutaneous saline (3 mL). For LPS-pen pigs, all pigs received subcutaneous lipopolysaccharide (LPS; 300 μg/kg BW; E. coli O111:B4; in 3 mL of saline). For the last treatment, eight pigs were randomly …

Functional Impact Of A Cancer-Related Variant In Human Δ1‑Pyrroline-5-Carboxylate Reductase 1, Oseeyi I. Daudu, Kaylen R. Meeks, Lu Zhang, Javier Seravalli, John J. Tanner, Donald F. Becker

Department of Biochemistry: Faculty Publications

Pyrroline-5-carboxylate reductase (PYCR) is a proline biosynthetic enzyme that catalyzes the NAD(P)H-dependent reduction of Δ¹-pyrroline-5-carboxylate (P5C) to proline. Humans have three PYCR isoforms, with PYCR1 often upregulated in different types of cancers. Here, we studied the biochemical and structural properties of the Thr171Met variant of PYCR1, which is found in patients with malignant melanoma and lung adenocarcinoma. Although PYCR1 is strongly associated with cancer progression, characterization of a PYCR1 variant in cancer patients has not yet been reported. Thr171 is conserved in all three PYCR isozymes and is located near the P5C substrate binding site. We found that …

Something Smells Fishy: How Lipid Mediators Impact The Maternal–Fetal Interface And Neonatal Development, Maranda Thompson, Arzu Ulu, Maheswari Mukherjee, Ana G. Yuil-Valdes, Melissa Thoene, Matthew Van Ormer, Rebecca Slotkowski, Teri Mauch, Ann Anderson-Berry, Corrine K. Hanson, Tara M. Nordgren, Sathish Kumar Natarajan

Department of Nutrition and Health Sciences: Faculty Publications

Normal pregnancy relies on inflammation for implantation, placentation, and parturition, but uncontrolled inflammation can lead to poor maternal and infant outcomes. Maternal diet is one modifiable factor that can impact inflammation. Omega-3 and -6 fatty acids obtained through the diet are metabolized into bioactive compounds that effect inflammation. Recent evidence has shown that the downstream products of omega-3 and -6 fatty acids may influence physiology during pregnancy. In this review, the current knowledge relating to omega-3 and omega-6 metabolites during pregnancy will be summarized.

Something Smells Fishy: How Lipid Mediators Impact The Maternal–Fetal Interface And Neonatal Development, Maranda Thompson, Arzu Ulu, Maheswari Mukherjee, Ana G. Yuil-Valdes, Melissa K. Thoene, Matthew Van Ormer, Rebecca Slotkowski, Teri Mauch, Ann Anderson-Berry, Corrine K. Hanson, Tara M. Nordgren, Sathish Kumar Natarajan

Department of Nutrition and Health Sciences: Faculty Publications

Normal pregnancy relies on inflammation for implantation, placentation, and parturition, but uncontrolled inflammation can lead to poor maternal and infant outcomes. Maternal diet is one modifiable factor that can impact inflammation. Omega-3 and -6 fatty acids obtained through the diet are metabolized into bioactive compounds that effect inflammation. Recent evidence has shown that the downstream products of omega-3 and -6 fatty acids may influence physiology during pregnancy. In this review, the current knowledge relating to omega-3 and omega-6 metabolites during pregnancy will be summarized.

Changes Of Air Pollutants In Urban Cities During The Covid-19 Lockdown-Sri Lanka, Buddhi Pushpawela, Sherly Shelton, Gayathri Liyanage, Sanduni Jayasekara, Dimuthu Rajapaksha, Akila Jayasundara, Lesty Das Jayasuriya

Department of Earth and Atmospheric Sciences: Faculty Publications

In response to the COVID-19 pandemic in early 2020, Sri Lanka underwent a nationwide lockdown that limited motor vehicle movement, industrial operations, and human activities. This study analyzes the impact of COVID-19 lockdown on carbon monoxide (CO), ozone (O₃), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and particulate matter (PM₁₀, PM_2.5) concentrations in two urban cities (Colombo and Kandy) in Sri Lanka, by comparison of data from the lockdown period (March to May 2020) with its analogous period of 2019 and 2021. The results showed that the percentage change of daytime …

Evolution And Molecular Basis Of A Novel Allosteric Property Of Crocodilian Hemoglobin, Chandrasekhar Natarajan, Anthony V. Signore, Naim M. Bautista, Federico G. Hoffmann, Jeremy R.H. Tame, Angela Fago, Jay F. Storz

School of Biological Sciences: Faculty Publications

The extraordinary breath-hold diving capacity of crocodilians has been ascribed to a unique mode of allosterically regulating hemoglobin (Hb)-oxygenation in circulating red blood cells. We investigated the origin and mechanistic basis of this novel biochemical phenomenon by performing directed mutagenesis experiments on resurrected ancestral Hbs. Comparisons of Hb function between the common ancestor of archosaurs (the group that includes crocodilians and birds) and the last common ancestor of modern crocodilians revealed that regulation of Hb-O₂ affinity via allosteric binding of bicarbonate ions represents a croc-specific innovation that evolved in combination with the loss of allosteric regulation by ATP binding. …

The Association Of Blood Ctdna Levels To Mutations Of Marker Genes In Colorectal Cancer, Fei Bai, Qian Du, Qingliang Zou, Lin Xu, Wei Dong, Xinlin Lv, Xiaorong Han, Huijun Zhou, Chi Zhang, Tao Lu

School of Biological Sciences: Faculty Publications

Background: Colorectal cancer (CRC) is a deadly and commonly diagnosed cancer. Cell‐free circulating tumor DNAs (ctDNA) have been used in the diagnosis and treatment of CRC, but there are open questions about the relationship between ctDNAs and CRC. Although mutations of genes detected by ctDNA in CRC have been studied, the quantitative relationship between ctDNA mutations and ctDNA concentration has not been addressed.

Aims: We hypothesized that there was an association between mutations of genes identified in ctDNAs and ctDNA concentration. His study examined this association in a population of CRC patients.

Methods: In 85 CRC patients, …