Digital Commons Network^™

Long-Term Variability Of Air Quality And Greenhouse Gas Emissions From Rice Crop Burning In Punjab During 2012–2020, Harsimranjit Kaur Romana, Dericks Praise Shukla, Ramesh P. Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

Punjab, India's primary rice and wheat production hub, has witnessed rapid expansion of paddy cultivation over the past two decades, driven by minimum support price incentives, changes in government policies, alignment of sowing with the monsoon season and the adoption of high-yielding varieties. This transition has intensified groundwater extraction and shortened the fallow period between rabi and kharif crop seasons, reducing the window between rice harvesting and wheat sowing, leading to widespread open-field burning of rice residue and recurrent post-monsoon air-quality deterioration across the Indo-Gangetic Plain. Despite numerous short-term or single-pollutant assessments, a spatially resolved, multi-pollutant and multi-decadal evaluation linking …

Next-Generation Biomedical Implants And Stimuli Responsive Soft Optical Arrays Via Surface Functionalized Elastomeric Materials, John M. Kapitan

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The demands of emerging technologies, such as soft robotics, stretchable electronics, and next generation biomedical implants, has led to the development of diverse polymeric and hybrid organic/inorganic materials specifically tuned to meet these challenges. These materials typically have low Young’s moduli and are inert with high chemical stability. However, this has led to materials that are static in nature, lacking any meaningful way of responding to changes in their environment and adapting to these changes. This has driven a shift towards the design, manufacturing, and characterization of various stimuli responsive surfaces, relying on precise control of surface chemical coatings and …

Design And Development Of Fluorescent Probes For Sensing And Bioimaging Of Nad(P)H, Intracellular Viscosity, And So2, Dilka Liyana Arachchige

Dissertations, Master's Theses and Master's Reports

Understanding the dynamic biochemical and biophysical changes within living systems is vital for advancing disease diagnosis and therapeutic development. This work presents the design and development of innovative fluorescent probes, based on cyanine and coumarin scaffolds, for the highly sensitive and selective detection of key metabolic and biophysical markers, NAD(P)H, mitochondrial viscosity, and sulfur dioxide (SO₂) in live cells and fruit fly larvae. A series of cyanine-based probes were engineered to undergo strong fluorescence enhancement upon reduction by NAD(P)H, enabling real-time visualization of metabolic fluctuations in cancer cells and Drosophila larvae. These probes exhibit excellent sensitivity, mitochondrial targeting capability, and …

Effect Of Inulin From Dahlia Tubers (Dahlia Variabilis) Extract On Insulitis Severity And Insulin Expression In Diabetic Rats, Ismawati Ismawati, Saryono Saryono, Mukhyarjon Mukhyarjon, Ilhami Romus, Veni Dayu Putri, Sri Yanti, Fitri Dyna, Nada Idzdihari Adesti

BioMedicine

Background: Dahlia (Dahlia variabilis), a widely cultivated ornamental plant in Indonesia, is known to contain 84.08% inulin in its tubers. Numerous studies have demonstrated the antidiabetic potential of inulin from various plant sources. However, most of the research is in the form of a mixture of inulin with other active substances, and no one has analyzed the effects of inulin derived from dahlia tubers. This study examines the effect of inulin from dahlia tuber extract on blood glucose levels, serum insulin expression, pancreatic tissue insulin expression, homeostatic model assessment of insulin resistance (HOMA-IR), and the extent of …

Enhanced Ctla-4 Blockade Anti-Tumor Immunity With Apg-157 Combination In A Murine Head And Neck Cancer, Daniel Sanghoon Shin, Saroj Basak, Mysore S Veena, Begoña Comin-Anduix, Arjun Bhattacharya, Tien S Dong, Albert Ko, Philip Han, Jonathan Jacobs, Neda A Moatamed, Luis Avila, Matteo Pellegrini, Marilene Wang, Eri S Srivatsan

Faculty, Staff and Student Publications

BACKGROUND: A phase I clinical study for patients with locally advanced H&N cancer with a new class of botanical drug APG-157 provided hints of potential synergy with immunotherapy. We sought to evaluate the efficacy of the combination of APG-157 and immune checkpoint inhibitors.

METHODS: CCL23, UM-SCC1 (human), and SCCVII (HPV-), MEER (HPV+) (murine) H&N cancer cell lines were utilized for in vitro and in vivo studies. We measured tumor growth by treating the mice with APG-157, anti-PD-1, and anti-CTLA-4 antibody combinations (8 groups). The tumor microenvironments were assessed by multi-color flow cytometry, immunohistochemistry, and RNA-seq analysis. Fecal microbiome was analyzed …

Discovery Of Strong 3-Nitro-2-Phenyl-2h-Chromene Analogues As Antitrypanosomal Agents And Inhibitors Of Trypanosoma Cruzi Glucokinase, Shane M. Carey, Destiny M. O’Neill, Garrett B. Conner, Julian Sherman, Ana Rodriguez, Edward L. D'Antonio

Natural Sciences Faculty Publications

Chagas disease is one of the world’s neglected tropical diseases, caused by the human pathogenic protozoan parasite Trypanosoma cruzi. There is currently a lack of effective and tolerable clinically available therapeutics to treat this life-threatening illness and the discovery of modern alternative options is an urgent matter. T. cruzi glucokinase (TcGlcK) is a potential drug target because its product, D-glucose-6-phosphate, serves as a key metabolite in the pentose phosphate pathway, glycolysis, and gluconeogenesis. In 2019, we identified a novel cluster of TcGlcK inhibitors that also exhibited anti-T. cruzi efficacy called the 3-nitro-2-phenyl-2H-chromene analogues. This was achieved by performing a target-based …

Recurrent Lymphoid And Myeloid Relapses Due To Treatment Cessations Reveal Natural History Of Ph-Positive B-All And Pose A Diagnostic Challenge, Shimin Hu, Elias J Jabbour, Collin Y Hu, Guilin Tang, Wei Wang, L Jeffrey Medeiros, Carlos Bueso-Ramos

Faculty, Staff and Student Publications

No abstract provided.

A Phytochemical Analysis Of Secondary Metabolites In Eupatorium Serotinum, Elise Snow

Theses and Dissertations

Phytochemistry, a subset of Natural Products Chemistry, studies chemically derived products from natural substances. Advances in this field have important applications in medicinal research due to the distinctive and unique properties of natural compounds. All metabolites are produced from the metabolic cycle, which is a pathway that provides energy for the organism. These metabolic compounds vary greatly and are classified based on their function within the organism. Primary metabolites are abundant and contribute to organism growth, development, and maintenance of energy. Secondary metabolites are found in lesser quantity and correlate to natural defense mechanisms. For example, salicylic acid is a …

Efficacy Of Gonacon Fertility Control Against Prairie Dogs And Potential For Uses On Other Rodent Species, Aaron B. Shiels, Emily W. Ruell, Jason E. Bruemmer

United States Department of Agriculture Wildlife Services: Staff Publications

Use of a contraceptive (i.e., fertility control) is attractive for rodent management where lethal control is unwanted. Although population reduction is generally unachievable with small-scale, short-term contraceptive use, reduced juvenile recruitment is achievable. The injectable immunocontraceptive vaccine GonaCon (active ingredient: gonadotropin releasing hormone [GnRH]) was registered in 2022 by the United States Environmental Protection Agency (EPA) for controlling fertility of female prairie dogs (Cynomys, a type of ground squirrel) in urban/suburban settings. Here we: 1) describe past research, including a replicated field study in Colorado (GonaCon treatment vs. control sites) testing efficacy of GonaCon in prairie dogs, which …

Discovery, Structure-Activity Relationship And In Vitro Anticancer Activity Of Small-Molecule Inhibitors Of The Protein-Protein Interactions Between Af9/Enl And Af4 Or Dot1l, Xin Li, Xiaowei Wu, Shenyou Nie, Jidong Zhao, Yuan Yao, Fangrui Wu, Chandra Bhushan Mishra, Md Ashraf-Uz-Zaman, Bala Krishna Moku, Yongcheng Song

Faculty, Staff and Students Publications

Simple Summary

Chromosomal translocations involving the mixed lineage leukemia (MLL) gene generate potent fusion oncogenes and cause acute myeloid leukemia or lymphocytic leukemia, which account for ~75% infant and 5–10% child/adult acute leukemia cases with a poor prognosis (5-year survival rates < 45%). Protein–protein interactions between the most frequent MLL fusion partner proteins AF9/ENL and AF4 or histone methyltransferase DOT1L are critical to malignant gene expression and are therefore a potential drug target for cancer. Compound screening followed by medicinal chemistry studies identified several novel small-molecule inhibitors showing strong inhibition of these protein–protein interactions, significant suppression of characteristic gene expression, and robust cellular anticancer activities with negligible cytotoxicity. These compounds are useful chemical probes for biological studies of these protein–protein interactions, as well as pharmacological leads for further drug development against MLL-rearranged and other leukemias.

Abstract

Chromosomal translocations involving the mixed lineage leukemia (MLL) gene cause 5–10% acute leukemias with poor clinical outcomes. Protein–protein interactions (PPI) between the most frequent MLL fusion partner proteins AF9/ENL and AF4 or histone methyltransferase DOT1L are drug targets for MLL-rearranged (MLL-r) leukemia. Several benzothiophene-carboxamide compounds were identified as novel inhibitors of these PPIs with IC₅₀ values as …

A Computational Study On The Impact Of Anchoring Groups On The Optical And Electronic Properties Of Triphenylamine-Based Dyes For Dye-Sensitized Solar Cell Applications, Geradius Deogratias, Grace Kinunda

Tanzania Journal of Science

Anchoring groups are crucial for enhancing the performance of dye-sensitized solar cells (DSSCs). For instance, cyanoacrylic acid serves as the primary anchoring group in DSSC due to its crucial elements required for effective electron transport. However, it suffers from degradation. To address this limitation, this study proposes alternative cyano-based anchoring groups for sensitizers. Density functional theory (DFT) and time-dependent DFT were used to investigate the optical and electronic properties of the dyes. The studied dyes (excluding the dye containing OH group) displayed three absorption bands within the visible and NIR regions. Low-energy peaks ranged from 498 to 576 nm, corresponding …

Girls In Stem! Elementary Afterschool Six-Week Curriculum, Jess Li, Samavi Rafique

Honors Program: Expanded Learning Clubs

No abstract provided.

Structure-Activity Relationship And Antitumor Activity Of 1,4-Pyrazine-Containing Inhibitors Of Histone Acetyltransferases P300/Cbp, Shenyou Nie, Fangrui Wu, Jingyu Wu, Xin Li, Chao Zhou, Yuan Yao, Yongcheng Song

Faculty, Staff and Students Publications

Acetylation of histone lysine residues by histone acetyltransferase (HAT) p300 and its paralog CBP play important roles in gene regulation in health and diseases. The HAT domain of p300/CBP has been found to be a potential drug target for cancer. Compound screening followed by structure-activity relationship studies yielded a novel series of 1,4-pyrazine-containing inhibitors of p300/CBP HAT with their IC50s as low as 1.4 μM. Enzyme kinetics and other studies support the most potent compound 29 is a competitive inhibitor of p300 HAT against the substrate histone. It exhibited a high selectivity for p300 and CBP, with negligible activity on …

Development Of A Novel Vertebrate Pesticide For The Invasive Small Indian Mongoose, Carmen Antaky, Steven C. Hess, Israel Leinbach, Robert T. T. Sugihara, Emily W. Ruell, Shane Siers

United States Department of Agriculture Wildlife Services: Staff Publications

Small Indian mongooses are detrimental introduced predators in the United States, where they depredate native species, serve as vector of disease, and threaten public safety. Due to the risk of accidental introduction to mongoose-free islands, high cost and limitations to trapping, and no national (Section 3) Environmental Protection Agency (EPA)-registered toxicants for mongoose control, there is a need for an efficacious toxic bait for mongooses for use in conservation areas and at points of entry in the United States. Over the last five years, the National Wildlife Research Center (NWRC) worked to develop a toxic bait for mongooses for registration …

Structure, Function And Inhibition Of Critical Protein-Protein Interactions Involving Mixed Lineage Leukemia 1 And Its Fusion Oncoproteins, Xin Li, Yongcheng Song

Faculty, Staff and Students Publications

Mixed lineage leukemia 1 (MLL1, also known as MLL or KMT2A) is an important transcription factor and histone-H3 lysine-4 (H3K4) methyltransferase. It is a master regulator for transcription of important genes (e.g., Hox genes) for embryonic development and hematopoiesis. However, it is largely dispensable in matured cells. Dysregulation of MLL1 leads to overexpression of certain Hox genes and eventually leukemia initiation. Chromosome translocations involving MLL1 cause ~ 75% of acute leukemia in infants and 5-10% in children and adults with a poor prognosis. Targeted therapeutics against oncogenic fusion MLL1 (onco-MLL1) are therefore needed. Onco-MLL1 consists of the N-terminal DNA-interacting domains …

Synthesis, Structure-Activity Relationships, And Antiviral Activity Of Allosteric Inhibitors Of Flavivirus Ns2b-Ns3 Protease, Shenyou Nie, Yuan Yao, Fangrui Wu, Xiaowei Wu, Jidong Zhao, Yuanda Hua, Jingyu Wu, Tong Huo, Yi-Lun Lin, Alexander R Kneubehl, Megan B Vogt, Josephine Ferreon, Rebecca Rico-Hesse, Yongcheng Song

Faculty, Staff and Students Publications

Flaviviruses, including Zika, dengue and West Nile virus, are important human pathogens. The highly conserved NS2B-NS3 protease of Flavivirus is essential for viral replication and therefore a promising drug target. Through compound screen followed by medicinal chemistry studies, a novel series of 2,5,6-trisubstituted pyrazine compounds are found to be potent, allosteric inhibitors of Zika virus protease (ZVpro) with IC50 values as low as 130 nM. Their structure-activity relationships are discussed. The ZVpro inhibitors also inhibit homologous proteases of dengue and West Nile virus and their inhibitory activities are correlated. The most potent compounds 47 and 103 potently inhibited Zika virus …

Study Of Student Resource Use In Introductory Chemistry Courses, Sarah E. Melvin

College of Graduate Studies: Theses & Dissertations

According to the U.S. Government Accountability Office (GAO), college textbook prices have increased by 186% from 1986 to 2004.1 The impact of rising cost of textbooks is increasingly apparent as students are becoming more selective in the courses they enroll in, as well as more concerned with the quality of the learning experience they receive once enrolled in a course.¹ In response to high textbook prices, open-education resources (OER) are increasingly becoming more accepted for student use as an alternative to traditional textbook options. OERs are open-source textbook and/or materials that are free to use without worrying about copyright …

Small-Molecule Inhibitor Of Af9/Enl-Dot1l/Af4/Aff4 Interactions Suppresses Malignant Gene Expression And Tumor Grow, Fangrui Wu, Shenyou Nie, Yuan Yao, Tong Huo, Xin Li, Xiaowei Wu, Jidong Zhao, Yi-Lun Lin, Yinjie Zhang, Qianxing Mo, Yongcheng Song

Faculty, Staff and Students Publications

Chromosome translocations involving mixed lineage leukemia (MLL) gene cause acute leukemia with a poor prognosis. MLL is frequently fused with transcription cofactors AF4 (~35%), AF9 (25%) or its paralog ENL (10%). The AHD domain of AF9/ENL binds to AF4, its paralog AFF4, or histone-H3 lysine-79 (H3K79) methyltransferase DOT1L. Formation of AF9/ENL/AF4/AFF4-containing super elongation complexes (SEC) and the catalytic activity of DOT1L are essential for MLL-rearranged leukemia. Protein-protein interactions (PPI) between AF9/ENL and DOT1L/AF4/AFF4 are therefore a potential drug target.

Methods: Compound screening followed by medicinal chemistry was used to find inhibitors of such PPIs, which were examined for their biological …

Phosphorylation Of Adp-Glucose Pyrophosphorylase During Wheat Seeds Development, Danisa M. L. Ferrero, Claudia V. Piattoni, Matías D. Asencion Diez, Bruno E. Rojas, Matías D. Hartman, Miguel A. Ballicora, Alberto A. Iglesias

Chemistry: Faculty Publications and Other Works

Starch is the dominant reserve polysaccharide accumulated in the seed of grasses (like wheat). It is the most common carbohydrate in the human diet and a material applied to the bioplastics and biofuels industry. Hence, the complete understanding of starch metabolism is critical to design rational strategies to improve its allocation in plant reserve tissues. ADP-glucose pyrophosphorylase (ADP-Glc PPase) catalyzes the key (regulated) step in the synthetic starch pathway. The enzyme comprises a small (S) and a large (L) subunit forming an S2L2 heterotetramer, which is allosterically regulated by orthophosphate, fructose-6P, and 3P-glycerate. ADP-Glc PPase was found in a phosphorylated …

Use Of Otolith Chemistry To Assess Recruitment And Habitat Use Of A White Bass Fishery In A Nebraska Reservoir, Matthew A. Perrion, Mark A. Kaemingk, Keith D. Koupal, Casey W. Schoenebeck, Nate A. Bickford

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Managing fisheries that exhibit variable annual recruitment is challenging, and maintenance stockings are often prescribed to minimize interannual population variation. Maintenance stockings are costly and may not be necessary if sufficient natural recruitment is occurring. Therefore, developing tools and techniques that can collectively assess hatching origin and subsequent habitat use of individuals would be valuable. Herein, we aimed to assess the efficacy of otolith chemistry techniques to (1) determine whether there was evidence of natural recruitment within an annually stocked white bass population and (2) examine the potential to describe spatial reservoir use of these age-0 fish. A sample of …

Green Chemistry In United States Science Policy, Emily Jarvis

Chemistry and Biochemistry Faculty Works

Although optimizing each of the Twelve Principles of Green Chemistry is necessary for achieving the greenest possible chemistry in the lab, there are additional creative ways to promote green chemistry not encompassed by these. Communicating to society the importance of green chemistry beyond the laboratory is essential. Of course, doing this effectively presents distinct challenges to those encountered when designing chemical syntheses. Here, I discuss several observations from my time working in federal science policy as an American Association for the Advancement of Science/American Chemical Society Congressional Science Fellow in the United States Senate. I suggest a practical science policy …

Structure-Activity Relationship Studies Of Synthetic Cathinones And Related Agents, Rachel A. Davies

Theses and Dissertations

Synthetic cathinones and related agents represent an international drug abuse problem, and at the same time an important class of clinically useful compounds. Structure-activity relationship studies are needed to elucidate molecular features underlying the pharmacology of these agents. Illicit methcathinone (i.e., MCAT), the prototype of the synthetic cathinone class, exists as a racemic mixture. Though the differences in potency and target selectivity between the positional and optical isomers of synthetic cathinones and related agents have been demonstrated to have important implications for abuse and therapeutic potential, the two MCAT isomers have never been directly compared at their molecular targets: the …

Lignocellulosic Biomass Derived Activated Carbon For Energy Storage And Adsorption, Changle Jiang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Lignocellulosic biomass has been converted to hierarchical porous carbon materials which possess macro-, meso- and micro-pores. The natural structure of porous lignocellulosic structure was preserved during activation with further developed porosity by the activation. The activated carbon can be well applied to electrochemical double layer capacitor for transportation storage of ions as well as adsorbent materials for metal ion removal from wastewater.

The first chapter of this dissertation presents an introduction of biomass derived carbon and its applications. In the second chapter, both direct and indirect activation methods using carbon dioxide were adopted in this study. The results show that …

Despite Similar Perceptions And Attitudes, Postbaccalaureate Students Outperform In Introductory Biology And Chemistry Courses, Erin E. Shortlidge, Liz Rain-Griffith, Chloe Shelby, Gwen Shusterman, Jack Barbera

Biology Faculty Publications and Presentations

Embedding active learning is a common mechanism for meeting science, technology, engineering, and mathematics (STEM) education reform goals. Researchers have identified student benefits from such strategies, yet these benefits may not be universal for all students. We sought to identify how students at a nontraditional university perceive introductory biology and chemistry courses, and whether perceptions relate to course type, performance, or student status. We surveyed students (n = 601) using open-ended prompts regarding their perceptions of factors that impact their learning and interest, and about specific learning strategies. Generally, students did not differ in what influenced their learning or …

Conformationally-Controlled Late-Stage Modifications For Sar Studies Of The C-3-Glcp Moiety Of Ipomoeassin F, Lucas Whisenhunt

Graduate Theses and Dissertations

The resin glycoside, ipomoeassin F has been shown to be extremely potent against multiple cancer lines (IC50 = 4.2-36 nM). However, the mechanism of action of this potent and complex natural product is still not fully understood. The α,β-unsaturated esters of the glucosyl moiety have been shown to be vital for the overall cytotoxicity of ipomoeassin F. Nevertheless, the importance of the tigloyl ester of the glucosyl moiety is still largely unknown. This work aimed to study the pharmacophore importance of the tigloyl ester by creating, an efficient, scalable, and flexible synthesis route for various analogs. The 18-linear step synthesis …

Deconvoluting The Effects Of Surface Chemistry And Nanoscale Topography: Pseudomonas Aeruginosa Biofilm Nucleation On Si-Based Substrates, Jing Zhang, Jingling Huang, Carmen Say, Robert L. Dorit, Kate Queeney

Chemistry: Faculty Publications

Hypothesis

The nucleation of biofilms is known to be affected by both the chemistry and topography of the underlying substrate, particularly when topography includes nanoscale (nm) features. However, determining the role of topography vs. chemistry is complicated by concomitant variation in both as a result of typical surface modification techniques. Analyzing the behavior of biofilm-forming bacteria exposed to surfaces with systematic, independent variation of both topography and surface chemistry should allow differentiation of the two effects.

Experiments

Silicon surfaces with reproducible nanotopography were created by anisotropic etching in deoxygenated water. Surface chemistry was varied independently to create hydrophilic (OH- terminated) …

Chemical Mechanism Of Antioxidation Of Theaflavin, Xie Hong, Luo Zhicong, Li Xican

Food and Machinery

To research the antioxidant chemical mechanism of theaflavin, the antioxidant activities of theaflavin were measured in vitro using several chemical models, including DPPH· (1,1-diphenyl-2-picryl-hydrazyl) scavenging, ABTS⁺· \[2,2’-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid)\] scavenging, and Cu²⁺-reducing power assays, which was compared with the positive control Trolox. In these assays, theaflavin along with positive control Trolox exhibited dose-dependently antioxidant abilities. The relative antioxidant levels of theaflavin vs Trolox (i.e. IC_50,Trolox/IC_{50,theaflavin} value) were calculated as 2.57, 3.13 and 3.74, respectively for DPPH·-scavenging assay, ABTS⁺·-scavenging assay, and Cu²⁺-reducing power assay. In conclusion, theaflavin possessed higher antioxidant …

Summary Of The Stock Structure Information Used For Determining Spatial Management Of The Index Species For The Scalefish Resources Of Northern Western Australia, Daniel J. Gaughan, Stephen J. Newman, Corey B. Wakefield

WA Marine Stewardship Council report series

This paper was specifically developed in response to issues raised in an assessment of the Pilbara Trap Managed Fishery (PTMF) against the fishery sustainability standard of the Marine Stewardship Council (MSC).

Biological Activities Of Phenolic Compounds Extracted From Some Plant Species From East Kalimantan Province, Indonesia, Franxisca Mariani

Chulalongkorn University Theses and Dissertations (Chula ETD)

Ten medicinal plants used in this study are based on the experience of Dayak tribes. The scientific information about these plants are still limited, therefore, the objective of the present study was to analyze their phenolic content and biological activities. A selected species was subjected to successive extraction and compound isolation. The total phenolic content and total antioxidant capacity were analyzed by using Folin-Ciocalteu reagent and the phosphomolybdenum method, respectively. DPPH and ABTS assays were used for analyzing antioxidant activities. The antibacterial activity was performed against six bacterial strains by agar well diffusion and microdilution methods. The anti-tyrosinase activity used …

Connecting Chemistry To Community With Deliberative Democracy, Regis Komperda, Jack Barbera, Erin Shortlidge, Gwen Shusterman, Stem Education And Equity Institute, Portland State University

Biology Faculty Publications and Presentations

Science education communities have called for rethinking curricula to improve student understanding of the nature of science and the role of science in addressing controversial modern issues such as climate change, energy policy, and pollution levels. One approach to meeting this call is integrating these topics into class activities that require students to use discussion and scientific approaches to solve problems and deliberate potential policy solutions. Deliberative democracy (DD) is one such active learning approach in which students work in peer groups to reach a consensus on a scientific topic relevant to both real-world issues and course content. During DD …