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Biology

Theses/Dissertations

2021

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Full-Text Articles in Cell and Developmental Biology

Analysis Of Spore Shape Determination In Streptomyces, Ning Sun Dec 2021

Analysis Of Spore Shape Determination In Streptomyces, Ning Sun

Electronic Theses and Dissertations

Streptomycetes are Gram-positive, soil-dwelling bacteria that possess a complex life cycle with the alternation of vegetative mycelium, aerial mycelium, and spores. Streptomyces. coelicolor spore maturation is a complex process that involves spore shape metamorphosis from cylindrical pre-spores into ellipsoid spores, but the details of this process have remained enigmatic. Previously, our lab identified a novel gene ssdA that might play a role in spore shape determination using a transposon-based insertion mutagenesis in S. coelicolor. In this study, I isolated a S. coelicolor ssdA-null mutant that showed increased colony hydrophobicity and misshapen spores in sizes and shapes, confirming the …


Development Of A Muc16-Targeted Near-Infrared Antibody Probe For Fluorescence-Guided Surgery Of Pancreatic Cancer, Madeline T. Olson Dec 2021

Development Of A Muc16-Targeted Near-Infrared Antibody Probe For Fluorescence-Guided Surgery Of Pancreatic Cancer, Madeline T. Olson

Theses & Dissertations

Pancreatic cancer (PDAC) is an extremely lethal disease with an overall survival rate of 10%. Surgery remains the only potentially curative treatment option, but resections are complicated by infiltrative disease, proximity of critical vasculature, peritumoral inflammation, and dense stroma. Surgeons are limited to tactile and visual cues to differentiate cancerous tissue from normal tissue. Furthermore, translating preoperative images to the intraoperative setting poses additional challenges for tumor detection, and can result in undetected and unresected lesions. Thus, PDAC has high rates of incomplete resections, and subsequently, disease recurrence. Fluorescence-guided surgery (FGS) has emerged as a method to improve intraoperative detection …


Investigating Antimicrobial Properties Of Snake Venoms Against B. Cereus, B. Subtilis, E. Coli, And P. Vulgaris, Savannah Berger Dec 2021

Investigating Antimicrobial Properties Of Snake Venoms Against B. Cereus, B. Subtilis, E. Coli, And P. Vulgaris, Savannah Berger

Honors Program Theses and Research Projects

The increasing incidence of antibiotic resistant bacterial infections has provoked the attention of health officials and scientists as a major threat to global public health. Antibiotic resistance is the product of overprescription by doctors, ineffective or shortened dosing by the patient, and more. When a bacterial infection is ineffectively treated as such, persistent pathogenic cells are given the opportunity to proliferate and spread their resistance to other cells. With bacteria utilizing such tools to fight and ultimately resist our current treatment methods, investigation towards the next novel mechanism of inhibition is essential. Venom is of particular interest to many scientists …


Regional Reprogramming And The Small Intestine: Analysis And Modeling Of Adaptive Regeneration Of The Epithelium, Sarah Elizabeth Waye Dec 2021

Regional Reprogramming And The Small Intestine: Analysis And Modeling Of Adaptive Regeneration Of The Epithelium, Sarah Elizabeth Waye

Arts & Sciences Electronic Theses and Dissertations

The small intestine in homeostasis is capable of regular regeneration, but in cases of massive injury like Short Bowel Syndrome, the innate human response often fails to fully compensate for the loss of nutrient absorptive surface area that accompanies bowel resection. Murine models display an active compensatory reaction deemed “adaptation” in which the surface area of the bowel is increased to accommodate nutrient absorptive needs. This observation has highlighted several gaps in knowledge regarding bowel adaptation. Firstly, what occurs on a molecular level in murine models during adaptation? Secondly, how can the findings in mice be applied to humans in …


An Insider's Guide To Cell Biology, Katie Ludwig Dec 2021

An Insider's Guide To Cell Biology, Katie Ludwig

Honors Projects

An Insider's Guide to Cell Biology is a comic book that follows Alanine the amoeba who tells the reader all about how the cell works.


Co-Option Of The Yolkless Oocyte Receptor For Crispr/Cas9 May Induce Transient Sterility In Female Drosophila Grimshawi Flies, Bronwyn Miller Dec 2021

Co-Option Of The Yolkless Oocyte Receptor For Crispr/Cas9 May Induce Transient Sterility In Female Drosophila Grimshawi Flies, Bronwyn Miller

University of New Orleans Theses and Dissertations

Evolutionary developmental biology has historically used generalist model organisms like Drosophila melanogaster. The Hawaiian Drosophilidae radiation, which occurred just 25 million years ago, is an ideal lineage for work in Evo-Devo. Hawaiian flies make up 25% of the world’s Drosophila species and extreme diversity is seen throughout the group. D. grimshawi is a generalist Hawaiian picture-wing fly that has served as a model for the Hawaiian Drosophilidae radiation. However, D. grimshawi’s power and use as a model organism is constrained by our lack of ability to manipulate its genome. In this work, I attempted to edit the genome of …


Mutant Kras Alters Extracellular Vesicle Microrna Sorting In Pancreatic Cystic Neoplasms, Rachel L. Dittmar Dec 2021

Mutant Kras Alters Extracellular Vesicle Microrna Sorting In Pancreatic Cystic Neoplasms, Rachel L. Dittmar

Dissertations & Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest cancers by organ site with a 5-year survival rate of just 10.8%. This is largely because most patients do not experience symptoms until the disease has already metastasized. The best hope to cure PDAC is surgery, which can only be done with a curative intent at an early stage when the disease is localized. There are no reliable circulating, body-fluid-based biomarkers to detect early stage PDAC or its precursor lesions in a timely manner for effective surgical intervention. When potential PDAC precursor lesions, such as mucinous pancreatic cysts are found, there are …


The Multifaceted Role Of Ccar-1 In The Alternative Splicing And Germline Regulation In Caenorhabditis Elegans, Doreen Ikhuva Lugano Oct 2021

The Multifaceted Role Of Ccar-1 In The Alternative Splicing And Germline Regulation In Caenorhabditis Elegans, Doreen Ikhuva Lugano

USF Tampa Graduate Theses and Dissertations

The Cell Division Cycle and Apoptosis Regulator (CCAR) family members are an enigmatic family of proteins regulating metabolism, cancer, apoptosis, DNA damage, and stress. Mammals have CCAR family members, CCAR1 and CCAR2/DBC1, which evolved from the founding family member CCAR-1/LST-3 expressed in Caenorhabditis elegans. Several studies have shown the importance of understanding these proteins' function in standard and altered physiological processes. Our studies aim to understand the genome-wide alternative splicing and germline regulation of Caenorhabditis elegans CCAR-1 in normal and heat shock conditions. Recently, mammalian CCAR family member CCAR2/DBC1 regulates the alternative splicing by forming a complex with ZNF326. This …


Clinically Relevant Dosage Of Vancomycin Does Not Negatively Impact Periosteum Derived Osteoblast Precursor Cellular Functions, Alexis Hernandez Sep 2021

Clinically Relevant Dosage Of Vancomycin Does Not Negatively Impact Periosteum Derived Osteoblast Precursor Cellular Functions, Alexis Hernandez

Seton Hall University Dissertations and Theses (ETDs)

Surgical site infections (SSI) can develop post-operatively and carry significant clinical and financial implications. SSI can carry a cost of up to $30,000 per case, as well as an estimated 6 day longer hospitalization. Patients with Type II Diabetes (DM) have an increased susceptibility to infection and suffer from poor bone healing overall. Therefore, diabetic patients who have undergone orthopedic surgery risk both an increased chance of developing an SSI as well as suboptimal bone healing. Vancomycin and other antibiotics have traditionally been used prophylactically to prevent infection, however the effect of vancomycin on bone healing in a diabetic population …


Mechanisms Of Substrate Recognition By The Cul3-Based E3 Ligase, Katia Graziella De Oliveira Rebola Sep 2021

Mechanisms Of Substrate Recognition By The Cul3-Based E3 Ligase, Katia Graziella De Oliveira Rebola

Dissertations and Theses

Cul3-based E3 ligase is responsible for regulating a variety of cellular pathways, many of which are known to have profound effects on the proper function of multicellular organisms. Although progress over the past years has been truly impressive, our understanding of the mechanisms of E2 recruitment and selection by the BCR complex and all the roles that Cul3 plays on kidneys remains in its infancy. To explore these aspects, this dissertation aims to analyze the Cul3 complex using two different approaches: (1) We used the powerful tool of chimeric analysis to map the essential domain binding characteristics of Cul3 taking …


The Structural And Functional Role Of Photosensing In Rgs-Lov Proteins, Zaynab Jaber Sep 2021

The Structural And Functional Role Of Photosensing In Rgs-Lov Proteins, Zaynab Jaber

Dissertations, Theses, and Capstone Projects

Light provides organisms with energy and spatiotemporal information. To survive and adapt, organisms have developed the ability to sense light to drive biochemical effects that underlie vision, entrainment of circadian rhythm, stress response, virulence, and many other important molecularly driven responses. Blue-light sensing Light-Oxygen-Voltage (LOV) domains are ubiquitous across multiple kingdoms of life and modulate various physiological events via diverse effector domains. Using a small molecule flavin chromophore, the LOV domain undergoes light-dependent structural changes leading to activation or repression of these catalytic and non-catalytic effectors. In silico analyses of high-throughput genomic sequencing data has led to the marked expansion …


Testing Janzen’S Physiological Barrier Hypothesis Through Experimental Evolution And Biogeographic Studies On Sister Species Pairs, Vincent John Fasanello Aug 2021

Testing Janzen’S Physiological Barrier Hypothesis Through Experimental Evolution And Biogeographic Studies On Sister Species Pairs, Vincent John Fasanello

Arts & Sciences Electronic Theses and Dissertations

Background: Janzen’s physiological barrier hypothesis suggests that variation in the effectiveness of physiological barriers to dispersal underlies global patterns of speciation and biodiversity. He noted that because a species’ physiology often evolves to match the range of conditions it has experienced in evolutionary history, it is likely that lineages that occupy habitats with wider ranges of temperature variation will tend to be better at dispersing across thermal gradients and will therefore be less likely to speciate as a result of mountain barriers. Despite decades of research into different aspects of this fundamental hypothesis, its assumptions and predictions remain largely untested. …


Chemical Damage To Mrna And Its Impact On Ribosome Quality-Control And Stress-Response Pathways In Eukaryotic Cells, Liewei Yan Aug 2021

Chemical Damage To Mrna And Its Impact On Ribosome Quality-Control And Stress-Response Pathways In Eukaryotic Cells, Liewei Yan

Arts & Sciences Electronic Theses and Dissertations

Ribosome often faces defective adducts that disrupt its movement along the mRNA template. These adducts are primarily caused by chemical damage to mRNA and are highly detrimental to the decoding process on the ribosome. Hence, unless dealt with, chemical damage to RNA has been hypothesized to lead to the production of toxic protein products. Even more detrimental is the ability of damaged mRNA to drastically affect ribosome homeostasis through stalling. This in turn would lead to greatly diminished translation capacity of cells. Therefore, the inability of cells to recognize and resolve translational-stalling events is detrimental to proteostasis and could even …


Investigating The Differentiation And Functional Maturation Of Stem Cell-Derived Β Cells, Leonardo Velazco-Cruz Aug 2021

Investigating The Differentiation And Functional Maturation Of Stem Cell-Derived Β Cells, Leonardo Velazco-Cruz

Arts & Sciences Electronic Theses and Dissertations

Diabetes mellitus is a chronic and global disease rapidly growing in prevalence. Diabetes can be characterized by the dysfunction or death of the glucose sensing insulin secreting  cell.  cells are located within the islet of Langerhans (islet), a tissue within the pancreas. Human islets are critical for the study and treatment of diabetes. However, they can only be obtained from cadaveric organ donors. These cadaveric islets do not proliferate and can only be maintained in vitro for short periods of time, making their availability rare and fleeting. Stem cell-derived -like cells can be generated in indefinite amounts and …


An Assessment Of Inp/Zns As Potential Anti-Cancer Therapy: Quantum Dot Treatment Induces Stress On Hela Cells, Victoria Grace Davenport Aug 2021

An Assessment Of Inp/Zns As Potential Anti-Cancer Therapy: Quantum Dot Treatment Induces Stress On Hela Cells, Victoria Grace Davenport

MSU Graduate Theses

Indium Phosphide/Zinc Sulfide (InP/ZnS) quantum dots (QDs) are an emerging option in QD technologies for uses of fluorescent imaging as well as targeted drug and anti-cancer therapies based on their customizable properties. In this study we explored effects of InP/ZnS when treated with HeLa cervical cancer cells. We employed XTT viability assays, reactive oxygen species (ROS) analysis, and apoptosis analysis to better understand cytotoxicity extents at different concentrations of InP/ZnS. In addition, we compared the transcriptome profile from the QDtreated HeLa cells with that of untreated HeLa cells to identify changes to the transcriptome in response to the QD. Intracellular …


Molecular Mechanisms Underlying Cell Fate Choice Within Specific Retinal Lineages, Estie Schick Jun 2021

Molecular Mechanisms Underlying Cell Fate Choice Within Specific Retinal Lineages, Estie Schick

Dissertations, Theses, and Capstone Projects

During development, retinal progenitor cells (RPCs) divide to form all of the cell types that make up the retina. Multipotent RPCs are competent to generate all retinal cell types, while restricted RPCs form specific lineages of cells. In particular, one genetically-defined RPC type preferentially gives rise to cone photoreceptors and horizontal cells. Many of the mechanisms that are responsible for directing cell fate choice within this lineage are unknown. This thesis largely focuses on examining the development of specific cell types and subtypes from restricted RPCs and on investigating the gene regulatory events that underlie cone photoreceptor and horizontal cell …


Analysis Of Symptom Expressions And Transmission Rates Caused By The Plant Pathogen Phytophthora Ramorum On Native Chaparral Plants From The Genus Arctostaphylos, Bharati Gaonker May 2021

Analysis Of Symptom Expressions And Transmission Rates Caused By The Plant Pathogen Phytophthora Ramorum On Native Chaparral Plants From The Genus Arctostaphylos, Bharati Gaonker

Natural Sciences and Mathematics | Biological Sciences Master's Theses

Phytophthora ramorum is the causal agent of Sudden Oak death (SOD), ramorum dieback and ramorum leaf blight which affect both forest environments and nurseries. This oomycete pathogen has had a huge economic impact on the nursery and lumber industry. Forests in California have experienced substantial mortality of oaks affecting the forest dynamics and diversity. Our research investigates four native species and two ornamental cultivars of plants, which belong to the genus Arctostaphylos (manzanita) and are considered to be new hosts for P. ramorum in the chaparral ecosystem of California. Symptom expression and transmission rates were analyzed on Arctostaphylos glauca, …


Characterizing The Gene Regulatory Network Required To Specify The Excitatory Neurotransmitter Phenotype Of V0v Spinal Interneurons, Amber Kellie Woodard May 2021

Characterizing The Gene Regulatory Network Required To Specify The Excitatory Neurotransmitter Phenotype Of V0v Spinal Interneurons, Amber Kellie Woodard

Theses - ALL

The majority of neurons within the spinal cord are interneurons. Interneurons make important connections with other cells that allow signals to be relayed between the brain and the rest of the body, and aid in functions such as locomotion. One key functional characteristic of interneurons is the neurotransmitter that they use to communicate with other cells. Interneurons that use GABA or glycine neurotransmitters to communicate have an inhibitory phenotype, while interneurons that use glutamate neurotransmitters have an excitatory neurotransmitter phenotype. Without the correct neurotransmitter phenotype, connections within the central nervous system will malfunction. It is therefore important to understand how …


A Forward Genetic Screen To Identify Human Genes Of Interest And Their Roles In Ovarian Cancer, Susan A. Ihejirika May 2021

A Forward Genetic Screen To Identify Human Genes Of Interest And Their Roles In Ovarian Cancer, Susan A. Ihejirika

Honors College Theses

Drosophila melanogaster, fruit flies, are very important for modeling and studying human diseases. This study identifies human genes of interest and their contributions to epithelial ovarian carcinogenesis and progression as well as the roles orthologs of these genes play in Drosophila melanogaster. This is important because ovarian cancer is the most common cause of death among the gynecological cancers. This identification of genes was carried out using a forward genetic screen employing the widely used GMR-Gal4 driver/UAS-transgene system. The GMR-Gal4 driver is commonly utilized to express transgenes in the developing eye of the fruit fly. Transgenes that are expressed using …


Biomedical Porcine Models For The Study Of Surgical Hemostasis, Hindlimb Ischemia, And Pancreatic Cancer, Shruthishree Aravind May 2021

Biomedical Porcine Models For The Study Of Surgical Hemostasis, Hindlimb Ischemia, And Pancreatic Cancer, Shruthishree Aravind

Theses & Dissertations

Murine models have dominated the world of biomedical research and comparative medicine since their development in the early 1900s. [1] While they may be suitable models to study proteomics and genomics, they may not serve as effective translational models. [2-4] Murine models do not accurately model the pathophysiology of human disease and are limited by their size, application of medical imaging and intervention, which reduces their overall preclinical predictive value. [2-4]

Porcine models on the other hand, are slowly and steadily bridging the gap between murine models and human patients. [5] Pigs …


Mitochondrial Distribution Of Glycine Receptors In Motor Neuron Cell Lines, Katsiaryna Milashevich May 2021

Mitochondrial Distribution Of Glycine Receptors In Motor Neuron Cell Lines, Katsiaryna Milashevich

Student Theses and Dissertations

Although non-essential, glycine plays an important role in major metabolic reactions and is most known for its anti-inflammatory effects. An accumulation of contemporary research has shown that glycine is able to stabilize membrane potential using glycine receptors at the cellular level and to protect mitochondrial function directly, whether it is from inflammation, heavy metal poisoning, or ischemia-induced neuroinflammation. In this research, the existence of a hypothetical mitochondrial glycine receptor is examined. Immunofluorescence imaging was used to examine the presence of the glycine receptor subunits alpha 1 and alpha 2 in both non- differentiated and differentiated neuroblastoma cell lines. The preliminary …


The Role Of Med31 And Med12 In Directing Adipogenesis Of Human Adult-Derived Mesenchymal Stem Cells, Joseph Straub May 2021

The Role Of Med31 And Med12 In Directing Adipogenesis Of Human Adult-Derived Mesenchymal Stem Cells, Joseph Straub

Master's Theses

Selective gene expression is crucial in maintaining the self-renewing and multipotent properties of stem cells. Mediator is a large, evolutionarily conserved, multisubunit protein complex that modulates gene expression by relaying signals from cell type-specific transcription factors to RNA polymerase II. In humans, this complex consists of 30 subunits arranged in four modules: head, middle, tail, and kinase. In our introduction, we show the state of the field of Mediator study with a focus on the critical kinase module. In the following chapters, we used siRNA knockdowns to investigate the roles of the highly-conserved core subunit MED31 and the kinase module …


The Role Of Med12 In Adipogenesis, Caroline Helen Rinderle May 2021

The Role Of Med12 In Adipogenesis, Caroline Helen Rinderle

Master's Theses

In order for any function to occur within a cell, transcription factors must be able to interact with genes. When this occurs, genes are expressed, and ultimately, proteins are translated and perform the specific function that needs to be done within the cell. In order for this to occur, genes must interact with transcription machinery. The Mediator complex recruits transcription factors to genes in order to promote cell-type specific gene expression. The Mediator complex is a multi-protein complex consisting of four modules: head, middle, tail, and kinase. The kinase module is known to dissociate from the rest of the complex …


Involvement Of The Ino80 Chromatin Remodeling Complex In Cell Division And Genomic Stability, Ethan Chen May 2021

Involvement Of The Ino80 Chromatin Remodeling Complex In Cell Division And Genomic Stability, Ethan Chen

Biomedical Engineering Undergraduate Honors Theses

Cell division is a vital biological process for growth and development in both single and multi-cellular organisms—whereby the cell must duplicate its organelles and genome in entirety and appropriately distribute the copied contents to the daughter cells. Cells undergo a cycle of two distinct phases: interphase and mitosis. During interphase, the cell replicates its genomic DNA (in the form of chromosomes) located within the nucleus. DNA replication is carried out in a euchromatin state, where the chromosome structure is loose and easily accessible by DNA polymerase and other replication enzymes. Upon the completion of replication, chromatin is condensed into highly …


Rna Modification Landscape And Its Contribution To Egg Production, Ian Thomas Rapisarda May 2021

Rna Modification Landscape And Its Contribution To Egg Production, Ian Thomas Rapisarda

Legacy Theses & Dissertations (2009 - 2024)

Germline stem cells differentiate into mature egg or sperm cells that go through the process of fertilization which gives rise to all sexually reproducing organisms. During this process of differentiation, germ cells undergo a switch from mitosis to meiosis that allows for proper development and specification of the future gamete. The mechanisms that facilitate this shift from mitosis to meiosis, however, are not well understood. To gain insight into this process, we used Drosophila oogenesis as our model. To identify what RNA modifications are present during oogenesis we genetically enriched for each stage of development and performed mass spectrometry. We …


Dna Damage And Aging In Progeria Compared To Healthy Cells., Ashtyn Marie Hill May 2021

Dna Damage And Aging In Progeria Compared To Healthy Cells., Ashtyn Marie Hill

Chancellor’s Honors Program Projects

No abstract provided.


The Role Of Med31 And Med12 In Directing Adipogenesis Of Human Adult-Derived Mesenchymal Stem Cells, Joseph Straub May 2021

The Role Of Med31 And Med12 In Directing Adipogenesis Of Human Adult-Derived Mesenchymal Stem Cells, Joseph Straub

Doctoral Dissertations

Selective gene expression is crucial in maintaining the self-renewing and multipotent properties of stem cells. Mediator is a large, evolutionarily conserved, multisubunit protein complex that modulates gene expression by relaying signals from cell type-specific transcription factors to RNA polymerase II. In humans, this complex consists of 30 subunits arranged in four modules: head, middle, tail, and kinase. In our introduction, we show the state of the field of Mediator study with a focus on the critical kinase module. In the following chapters, we used siRNA knockdowns to investigate the roles of the highly-conserved core subunit MED31 and the kinase module …


Examining The Mechanistic Roles Of Integrin Alpha-6 In Cancer Metastasis., Chase T. Clark Mar 2021

Examining The Mechanistic Roles Of Integrin Alpha-6 In Cancer Metastasis., Chase T. Clark

Honors College Theses

Metastasis- the spread of cancer cells from the primary tumor to the surrounding tissues- is responsible for 90% of cancer deaths. Integrin alpha-6 (ITGA6) is a specific transmembrane cell surface protein that functions in cell surface adhesion and signaling. ITGA6 is upregulated in many types of cancers and promotes the migration and invasion of cancer cells to surrounding tissues. It is my objective to determine the mechanism through which ITGA6 facilitates the migration of cancer cells through the extracellular matrix (ECM). These experiments helped to establish the role of ITGA6 in tumor development and provide focus for possible chemotherapeutic treatment. …


The Influence Of Autism Linked Gene Topoisomerase 3b (Top3b) On Neural Development In Zebrafish, Sydney Doolittle Mar 2021

The Influence Of Autism Linked Gene Topoisomerase 3b (Top3b) On Neural Development In Zebrafish, Sydney Doolittle

Honors College Theses

Autism Spectrum Disorder is a class of developmental disabilities characterized by a spectrum of social, communication, and behavioral impairments in affected individuals. Studies have shown these defects stem from abnormal brain development during critical periods during early development. The underlying genetic cause of these impairments is not well understood but is believed to be a combination of a complex pairing of genetic and environmental factors. One of the genetic factors that has been recognized to influence the phenotypic symptoms of ASD is the enzyme topoisomerase 3β (top3β.) Topoisomerases are responsible for the prevention of supercoiling during DNA replication. Top3β is …


Expression And Function Of Transcription Factors Foxa1, Hoxb13 And Cdx2 In Prostate Cancer, Hamsat B. Anwar Mar 2021

Expression And Function Of Transcription Factors Foxa1, Hoxb13 And Cdx2 In Prostate Cancer, Hamsat B. Anwar

University Honors Theses

Prostate cancer (PC) is the second leading cause of death in men, affecting around 190 thousand patients in 2020 alone (National Institute of Cancer, 2020). Much of the current research focuses on treatments for advanced PC, which is problematic due to the rapid evolution of tumors and development of treatment resistance. Cancer early detection presents a better approach to control and treat patients before they acquire an incurable disease. Earlier diagnosis of patients leads to better prognosis and a more comfortable treatment process (Etzioni et al., 2003). However, we currently lack molecular markers to stratify PC during its early stages. …