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Progress Towards The Development Of Asymmetric Conditions For Intramolecular Heteroatom/Dehydro-Diels-Alder Reactions For Synthesizing Furo[3,4-C] Pyranones And Anticancer Podophyllotoxins, Peter Mpaata

Theses and Dissertations

Furo[3,4-c] pyranone is a unique bicyclic molecular structure found in bioactive sesquiterpene isobolivianine and in artificial cytotoxic stilbene derivatives. The structure of furo[3,4-c] pyranone is analogous to cyclopenta[c] pyran structure found in potent cytotoxic iridoids like catapol. Chiral substrates for intramolecular hetero-Diels-Alder (IHDA) reaction have been synthesized in yields ranging from 39% to 81%. These compounds undergo [4+2] cycloaddition via ambimodal/ bispericyclic process to give a mixture of furo[3,4-c] pyranone in yields ranging 40-70% and aryl tetralin lactone derivatives. Density functional theory (DFT) calculations have been performed to gain insight into the mechanism leading to the formation of these compounds. …

High-Throughput Deconvolution Of 3d Organoid Dynamics At Cellular Resolution For Cancer Pharmacology With Cellos., Patience Mukashyaka, Pooja A Kumar, David J Mellert, Shadae Nicholas, Javad Noorbakhsh, Mattia Brugiolo, Elise T Courtois, Olga Anczuków, Edison Liu, Jeffrey Chuang

Faculty Research 2023

Three-dimensional (3D) organoid cultures are flexible systems to interrogate cellular growth, morphology, multicellular spatial architecture, and cellular interactions in response to treatment. However, computational methods for analysis of 3D organoids with sufficiently high-throughput and cellular resolution are needed. Here we report Cellos, an accurate, high-throughput pipeline for 3D organoid segmentation using classical algorithms and nuclear segmentation using a trained Stardist-3D convolutional neural network. To evaluate Cellos, we analyze ~100,000 organoids with ~2.35 million cells from multiple treatment experiments. Cellos segments dye-stained or fluorescently-labeled nuclei and accurately distinguishes distinct labeled cell populations within organoids. Cellos can recapitulate traditional luminescence-based drug response …

Physically And Chemically‑Crosslinked L‑Arginine‑Loaded Polyvinyl Alcohol‑ Hyaluronic Acid‑ Cellulose Nanocrystals Hydrogel Membranes For Wound Healing: Influence Of Crosslinking Methods On Biological Performance Of Membranes In‑Vitro, Elbadawy A. Kamoun, Elbadawy A. Kamoun

Nanotechnology Research Centre

Two types of polyvinyl alcohol-blended hyaluronic acid and cellulose nanocrystals (PVA/HA/CNCs) hydrogels membranes were developed as delivery agents for L-arginine using chemical/and/physical crosslinking methods for exploring biological performance of the obtained membranes. Chemically and physically/crosslinked membranes were fabricated by solution-casting and freeze-thawing techniques, respectively. The characterization of the crosslinked PVA/HA/CNCs/Larginine membranes were conducted by SEM, FTIR, TGA, swelling ratio, and in—vitro L-arginine release. Furthermore, applying two types of crosslinked membranes in vitro were investigated in terms of cytotoxicity, hemocompatibility, and cell adhesion affinity of HFB-4 cell line. Chemical and physical-crosslinked membranes were verified through the esterification and hydrogen bonds interactions, …

Intouch Week Of December 18, 2023, New York Medical College

InTouch

• Future Healers: 2023 Forum Highlights Medical Student Research
• Dr. Mitchell Cairo Awarded $2.6 Million Grant from Department of Defense for Pediatric Cancer Research
• Long COVID Patients at Greater Risk for Anxiety and PTSD New Study Finds
• NYMC Unveils the Portrait and Diploma of Alumnus Meyer J. Simon, M.D. ’25
• NYMC AMWA Chapter Hosts Medical Mavens Workshop
• Student Spotlight: Mentorship Propels Medical Student on Successful Research Path

Investigating The Geochemical Trends At The Sediment-Water Interface Of The Shallow And Eutrophic Utah Lake, Abidemi Sherif Aremu

Theses and Dissertations

The sources of phosphorus (P) in Utah Lake can be diverse, including natural and anthropogenic point and non-point sources, such as atmospheric deposition, soil erosion, and industrial and urban wastewater effluents. This study collected interface sediments, column water, porewater, and sediment cores across this vast water body. These samples were then analyzed for their mineralogic, organic, and elemental composition to characterize the geochemical nature of water and sediment at the water-sediment interface within Utah Lake. The average concentrations of P and other elements found in the column water of an individual site do not significantly differ across depth suggesting Utah …

Machine Learning And Metabolic Model Guided Crispri Reveals A Central Role For Phosphoglycerate Mutase In Chlamydia Trachomatis Persistence, Niaz Bahar Chowdhury, Nick Pokorzynski, Elizabeth A. Rucks, Scot P. Ouellette, Rey A. Carabeo, Rajib Saha

Department of Chemical and Biomolecular Engineering: Faculty Publications

Upon nutrient starvation, Chlamydia trachomatis serovar L2 (CTL) shifts from its normal growth to a non-replicating form, termed persistence. It is unclear if persistence is an adaptive response or lack of it. To understand that transcriptomics data were collected for nutrientsufficient and nutrient-starved CTL. Applying machine learning approaches on transcriptomics data revealed a global transcriptomic rewiring of CTL under stress conditions without having any global stress regulator. This indicated that CTL’s stress response is due to lack of an adaptive response mechanism. To investigate the impact of this on CTL metabolism, we reconstructed a genome-scale metabolic model of CTL (iCTL278) …

Mechanical Characterization Of Vertically Aligned Carbon Nanotube Forest Microelectrodes For Neural Interfacing, Spencer Mcleod Roberts

Theses and Dissertations

Silicon intracortical microelectrodes arrays (MEA) provide some of the best performance for brain computer interfaces but suffer from lifetime limitations that prevent clinical adoption. A primary contributor of lifetime limitations is the chronic foreign body response (FBR) which remains active in response to the brain tissue strain caused by implanted probes during brain micromotion. Designing probes with softer materials can reduce the chronic FBR and improve device lifetime. A high-aspect ratio CNT MEA could provide several advantages as an intracortical MEA but has yet to be mechanically characterized. CNT MEAs are infiltrated with 3 degrees of carbon infiltration and mechanically …

Genetic And Epigenetic Features Of Bilateral Wilms Tumor Predisposition In Patients From The Children’S Oncology Group Aren18b5-Q, Andrew J Murphy, Changde Cheng, Justin Williams, Timothy I Shaw, Emilia M Pinto, Karissa Dieseldorff-Jones, Jack Brzezinski, Lindsay A Renfro, Brett Tornwall, Vicki Huff, Andrew L Hong, Elizabeth A Mullen, Brian Crompton, Jeffrey S Dome, Conrad V Fernandez, James I Geller, Peter F Ehrlich, Heather Mulder, Ninad Oak, Jamie Maciezsek, Carolyn M Jablonowski, Andrew M Fleming, Prahalathan Pichavaram, Christopher L Morton, John Easton, Kim E Nichols, Michael R Clay, Teresa Santiago, Jinghui Zhang, Jun Yang, Gerard P Zambetti, Zhaoming Wang, Andrew M Davidoff, Xiang Chen

Faculty, Staff and Student Publications

Developing synchronous bilateral Wilms tumor suggests an underlying (epi)genetic predisposition. Here, we evaluate this predisposition in 68 patients using whole exome or genome sequencing (n = 85 tumors from 61 patients with matched germline blood DNA), RNA-seq (n = 99 tumors), and DNA methylation analysis (n = 61 peripheral blood, n = 29 non-diseased kidney, n = 99 tumors). We determine the predominant events for bilateral Wilms tumor predisposition: 1)pre-zygotic germline genetic variants readily detectable in blood DNA [WT1 (14.8%), NYNRIN (6.6%), TRIM28 (5%), and BRCA-related genes (5%)] or 2)post-zygotic epigenetic hypermethylation at 11p15.5 H19/ICR1 that may require analysis of …

Transcriptional Profiles Of Pulmonary Artery Endothelial Cells In Pulmonary Hypertension, Navneet Singh, Carsten Eickhoff, Augusto Garcia‑Agundez, Paul Bertone, Sunita S. Paudel, Dhananjay T. Tambe, Leslie A. Litzky, Katherine Cox‑Flaherty, James R. Klinger, Sean F. Monaghan, Christopher J. Mullin, Mandy Pereira, Thomas Walsh, Mary Whittenhall, Troy Stevens, Elizabeth O. Harrington, Corey E. Ventetuolo

University Faculty and Staff Publications

Pulmonary arterial hypertension (PAH) is characterized by endothelial cell (EC) dysfunction. There are no data from living patients to inform whether differential gene expression of pulmonary artery ECs (PAECs) can discern disease subtypes, progression and pathogenesis. We aimed to further validate our previously described method to propagate ECs from right heart catheter (RHC) balloon tips and to perform additional PAEC phenotyping. We performed bulk RNA sequencing of PAECs from RHC balloons. Using unsupervised dimensionality reduction and clustering we compared transcriptional signatures from PAH to controls and other forms of pulmonary hypertension. Select PAEC samples underwent single cell and population growth …

Self‑Perceived Infertility Is Not Always Associated With Having Fewer Children: Evidence From German Panel Data, Arthur L. Greil, Desmond D. Wallac, Jasmin Passet‑Wittig, Julia Mcquillan, Martin Bujard, Michele H. Lowry

Department of Sociology: Faculty Publications

Proximate determinants theory considers infertility rates a risk factor for lower fertility rates, but the assumption that people who perceive infertility will have fewer children has not been tested. This study investigates the association of self-perceived infertility with the number of children people have had after 11 years. Infertility implies reduced chances of conception (rather than sterility), but people do not always consistently perceive infertility over time. If people who think they are infertile at one time can later report no infertility, then does self-perceived infertility necessarily lead to having fewer children? We answer this question by analyzing 11 waves …

Intracellular Negative Feedback Mechanisms In Blubber And Muscle Moderate Acute Stress Responses In Fasting Seals, Jessica G. Avalos, Elizabeth R. Piotrowski, Allison D. Northey, Daniel E. Crocker, Jane I. Khudyakov

Pacific Faculty Work

Animals may limit the cost of stress responses during key life history stages such as breeding and molting by reducing tissue sensitivity to energy-mobilizing stress hormones (e.g. cortisol). We measured expression of genes encoding glucocorticoid receptor (GR, NR3C1), GR inhibitor (FKBP5) and cortisol-inactivating enzyme (HSD11B2) in blubber and muscle of northern elephant seals before and after stress axis stimulation by adrenocorticotropic hormone (ACTH) early and late in a fasting period associated with molting. ACTH elevated cortisol levels for >24 h and increased FKBP5 and HSD11B2 expression while downregulating NR3C1 expression in blubber and muscle, suggesting robust intracellular negative feedback in …

Value And Impact Of Nurse Innovators Working In Academic, Industry, And Government Settings: A Qualitative Study, Olivia A. Lemberger

Dissertations

This dissertation explores the value and impact of nurse innovators working in academic, industry, and government settings. A qualitative descriptive study was chosen to understand the contributions of nurse innovators and the outcomes associated with their innovative endeavors. The purpose of this study is to better understand the contributions of nurse innovators by answering the following research questions: 1) How do nurses perceive that nursing innovation adds value to and/or impacts patients or the United States health care system? 2) What metrics/outcome measures do nurse innovators identify as relevant or useful to evaluate innovation success? And 3) What methods/resources do …

Case Law On American Indians: October 2022 - August 2023, Thomas P. Schlosser

American Indian Law Journal

No abstract provided.

Validation Of A Chimeric Proteins-Based Elisa For The Diagnosis Of Brucellosis In Kazakhstan, Aitbay Bulashev, Saule Eskendirova, Bakytkali Ingirbay, Alfiya Syzdykova, Fariza Zhagipar

Turkish Journal of Veterinary & Animal Sciences

This study aimed to compare the suitability of three chimeric recombinant outer membrane proteins of Brucella (rOmps 19 + 25, 19 + 31, and 25 + 31) for the diagnosis of bovine and sheep brucellosis using an indirect ELISA (i-ELISA). The diagnostic properties of these proteins in an i-ELISA were studied using blood serum samples from cattle and sheep with known positive and negative results for brucellosis based on the rose Bengal plate test (RBT), complement fixation test (CFT), and a commercial ELISA (c-ELISA) kit, as well as using animal sera from fresh foci of infection with unknown reactivity. rOmps19 …

Effect Of Thermo-Insulated Kid Hutch On Location Preference, Growth Performance, And Blood Haemato-Biochemical Indices Of Winter-Born Goat Kids (Capra Hircus), Ajoy Das, Dilip Kumar Mandal, Asish Debbarma, Muthupalani Karunakaran, Anupam Chatterjee, Debajyoti Sarkar

Turkish Journal of Veterinary & Animal Sciences

This study assessed the effect of thermo-insulated kid hutch (TIKH) on location preference, body surface temperature, growth performance, and blood haemato-biochemical indices of winter-born Black Bengal goat kids. Does were maintained in the same shed, born kids (n = 12) were divided into two groups along with mothers to begin experiments from day 1 of birth. The treatment group (TIKH) of kids was given a TIKH to which kids had free access, but not the adults. However, in the control group (CONT) kids were reared without TIKH. The floor surface temperature of TIKH was significantly (p < 0.05) higher at night as compared to goat shed in December (4.28%), January (3.98%), and February (7.72%). The interior roof surface of TIKH had 25.12%, 33.55%, 31.85%, 10.99%, and 4.37% higher (p < 0.01) temperatures at night compared to the roof surface temperature of the goat shed in December, January, February, March, and April, respectively. The presence of kids inside the TIKH at the age of 1–15 days was the greatest in morning (80.5%) and evening (72.2%). Between the ages of 16–-60 days, the preference of kids for the TIKH varied from 69.2% to 54.2% in the morning and from 70.0% to 66.7% in the evening. However, at the age of 61–75 days, kids’ preference for TIKH gradually declined in the morning (11.6%) and evening (19.9%) due to the increased inside temperature. Kids weaning weight was 23.25% higher (p < 0.05) in the TIKH group as compared to that of CONT. The average daily gain (0–30 days) was higher (41.34%; p < 0.05) in kids in the TIKH compared to the CONT shed. The haemato-biochemical profiles of kids were similar in both groups except for blood serum glucose, which was greater (p < 0.05) in kids of the TIKH than that of CONT shed. In conclusion, the provision of TIKH improved the growth and overall performance of winter-born Black Bengal goat kids during pre and postweaning periods.

Water Buffalo Social Networks During Their Activities On Pasture Under The Rain, Eleni Tsiobani, Maria Yiakoulaki, Nikolaos Hasanagas, Ioannis Antoniou

Turkish Journal of Veterinary & Animal Sciences

Water buffaloes exhibit various social structures during their activities on pasture, but the impact of abiotic factors (i.e. rainfall) on these structures remains unknown. While existing research has provided evidence concerning the effect of weather conditions on grazing animals’ behavior, they have not examined how animals differentiate their social organization within the herd during their activities on pasture under the rainfall. This study utilized social network analysis to construct, depict, and analyze the proximity networks among buffaloes in each activity they perform on pasture before, during, and after the rainfall. By applying various network indices, we have shown that water …

Noninvasive Pregnancy Detection In Wild Felids Using Enzyme Immunoassay Of Fecal 13, 14–Dihydro–15–Keto–Pgf2Α Metabolite (Pgfm), Nikitha Prakash, Suchitra Bhadravathi Raju, Sahadev Annayappa, Leena Gowda, Veena Malavalli Prabhushankar

Turkish Journal of Veterinary & Animal Sciences

The study was carried out on Panthera species (4 lions and 5 tigers) housed in Bannerghatta Biological Park, Bengaluru, and Sri Chamarajendra Zoological Gardens, Mysuru. Estrus behavior such as rolling, licking, nudging, chuffing, frequent urination, whitish discharge, vocalisation, lordosis and copulatory behavior such as vocalisation, allowed to be mounted, aggression towards male, mounting, and biting of the nape of female were exhibited both in lions and tigers which helped to identify the time of fecal sample collection. The study’s main aim was to carry out noninvasive and noncontact pregnancy detection in these wild felids. Feces samples collected from the female …

Lesion Detection In Women Breast’S Dynamic Contrast-Enhanced Magnetic Resonance Imaging Using Deep Learning, Sudarshan Saikia, Tapas Si, Darpan Deb, Kangkana Bora, Saurav Mallik, Ujjwal Maulik, Zhongming Zhao

Faculty, Staff and Student Publications

Breast cancer is one of the most common cancers in women and the second foremost cause of cancer death in women after lung cancer. Recent technological advances in breast cancer treatment offer hope to millions of women in the world. Segmentation of the breast's Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) is one of the necessary tasks in the diagnosis and detection of breast cancer. Currently, a popular deep learning model, U-Net is extensively used in biomedical image segmentation. This article aims to advance the state of the art and conduct a more in-depth analysis with a focus on the use …

Pathway Centric Analysis For Single-Cell Rna-Seq And Spatial Transcriptomics Data With Gsdensity, Qingnan Liang, Yuefan Huang, Shan He, Ken Chen

Faculty, Staff and Student Publications

Advances in single-cell technology have enabled molecular dissection of heterogeneous biospecimens at unprecedented scales and resolutions. Cluster-centric approaches are widely applied in analyzing single-cell data, however they have limited power in dissecting and interpreting highly heterogenous, dynamically evolving data. Here, we present GSDensity, a graph-modeling approach that allows users to obtain pathway-centric interpretation and dissection of single-cell and spatial transcriptomics (ST) data without performing clustering. Using pathway gene sets, we show that GSDensity can accurately detect biologically distinct cells and reveal novel cell-pathway associations ignored by existing methods. Moreover, GSDensity, combined with trajectory analysis can identify curated pathways that are …

The Western Channel Observatory: A Century Of Physical, Chemical And Biological Data Compiled From Pelagic And Benthic Habitats In The Western English Channel, Andrea J. Mcevoy, Angus Atkinson, Ruth L. Airs, Rachel Brittain, Ian Brown, Elaine S. Fileman, Helen S. Findlay, Caroline L. Mcneill, Clare Ostle, Tim J. Smyth, Paul J. Somerfield, Karen Tait, Glen A. Tarran, Simon Thomas, Claire E. Widdicombe, E. Malcolm S. Woodward, Amanda Beesley, David V.P. Conway, James Fishwick, Hannah Haines, Carolyn Harris, Roger Harris, Pierre Hélaouët, David Johns, Penelope K. Lindeque, Thomas Mesher, Abigail Mcquatters-Gollop, Joana Nunes, Frances Perry, Ana M. Queiros, Andrew Rees, Saskia Rühl, David Sims, Ricardo Torres, Stephen Widdicombe

School of Biological and Marine Sciences

The Western Channel Observatory (WCO) comprises a series of pelagic, benthic and atmospheric sampling sites within 40 km of Plymouth, UK, that have been sampled by the Plymouth institutes on a regular basis since 1903. This longevity of recording and the high frequency of observations provide a unique combination of data; for example temperature data were first collected in 1903, and the reference station L4, where nearly 400 planktonic taxa have been enumerated, has been sampled on a weekly basis since 1988. While the component datasets have been archived, here we provide the first summary database bringing together a wide …

Impacts Of Artificial Light At Night On The Early Life History Of Two Ecosystem Engineers, Svenja Tidau, Fraser T. Brough, Luis Gimenez, Stuart R. Jenkins, Thomas W. Davies

School of Biological and Marine Sciences

Sessile marine invertebrates play a vital role as ecosystem engineers and in benthic-pelagic coupling. Most benthic fauna develop through larval stages and the importance of natural light cycles for larval biology and ecology is long-established. Natural light-dark cycles regulate two of the largest ocean-scale processes that are fundamental to larvae’s life cycle: the timing of broadcast spawning for successful fertilisation and diel vertical migration for foraging and predator avoidance. Given the reliance on light and the ecological role of larvae, surprisingly little is known about the impacts of artificial light at night (ALAN) on the early life history of habitat-forming …

Vodka2: A Fast And Accurate Method To Detect Non-Standard Viral Genomes From Large Rna-Seq Data Sets, Emna Achouri, Sébastien A Felt, Matthew Hackbart, Nicole S Rivera-Espinal, Carolina B López

2020-Current year OA Pubs

During viral replication, viruses carrying an RNA genome produce non-standard viral genomes (nsVGs), including copy-back viral genomes (cbVGs) and deletion viral genomes (delVGs), that play a crucial role in regulating viral replication and pathogenesis. Because of their critical roles in determining the outcome of RNA virus infections, the study of nsVGs has flourished in recent years, exposing a need for bioinformatic tools that can accurately identify them within next-generation sequencing data obtained from infected samples. Here, we present our data analysis pipeline, Viral Opensource DVG Key Algorithm 2 (VODKA2), that is optimized to run on a parallel computing environment for …

Investigation Of Three Single-Nucleotide Polymorphisms (1252 G>A, 2534 G>A, And 2569 T>C) Of The Mbl1 Gene In Anatolian Buffaloes, Esma Gamze Aksel, Bi̇lal Akyüz

Turkish Journal of Veterinary & Animal Sciences

It has been reported that since the MBL gene is involved in the first step of infection and inflammation processes, it may be associated with susceptibility to bacterial and viral diseases in living organisms. In this study, it was aimed to determine the genotypic variation of Anatolian buffaloes in terms of three (1252G>A, 2534 G>A, and 2569 T>C) single nucleotide polymorphisms (SNPs) within the MBL-1 gene. For this purpose, 103 Anatolian buffaloes were genotyped for relevant SNPs by PCR-RFLP process. The allele and genotype frequencies of the examined samples were determined, and the population was examined for …

Virological And Pathological Investigation Of Canine Parvovirus-2 (Cpv-2) With The Assessment Of The Genetic Variability Of Field Strains, Zeynep Karapinar, Musa Karaman, İhsan Kisadere, Mustafa Usta, Mehmet Özkan Ti̇murkan

Turkish Journal of Veterinary & Animal Sciences

Canine parvovirus-2 (CPV-2), which is common worldwide, is a highly contagious pathogen in domestic dogs and some wild carnivore species. The agent causes a multisystemic infection in affected animals, especially acute hemorrhagic enteritis and fatal myocarditis in puppies. The study aimed to reveal the presence of virus in dogs with clinical symptoms of CPV-2 infection using virological, pathological, and immunohistochemical methods and make molecular characterization based on partial VP-2 gene of strains circulating in the region. As a result of PCR studies, 9 out of 16 rectal swab samples and 17 out of 38 blood samples were positive. A phylogenetic …

Cross-Seasonal Effects In A Sea Ice-Associated Sea Duck: Do Winter Conditions Affect Breeding Spectacled Eiders?, Randall J. Friendly

Biological Sciences

Climate change in the Arctic is more rapid than anywhere on the globe and changes in the marine environment can impact the distribution and abundance of Arctic and sub-Arctic species. Understanding how a species responds to climate change can aid conservation planning and recovery. Spectacled eiders (Somateria fischeri), sea ducks listed as "threatened" under the Endangered Species Act, winter at the Bering Sea and nest along the coastal areas of Alaska and Arctic Russia. Severity of winter conditions in the Bering Sea have been associated with both reduced annual survival and reduced breeding abundance and may have sublethal effects during …

Icy Insights: Decrypting The Depths With Novel Stochastic Techniques To Model And Mitigate Arctic Under-Ice Oil Spills, Kelsey A. Frazier

Engineering

The retreat and thinning of Arctic sea ice, driven by climate change, have increased the potential for maritime navigation in the region, thereby heightening concerns about the environmental impacts of potential oil spills in the Arctic. This dissertation, with a focus on the Beaufort and Chukchi Seas, seeks to develop a remote predictive method for assessing the subsurface features of Arctic sea ice, thereby facilitating rapid responses to Arctic oil spills without depending on time-consuming in situ measurements. The first paper of this dissertation addresses the need for oil spill modelers to understand oil movement along the subsurface of sea …

The Role Of Apex Predators, Habitat, And Seascape Complexity On Nearshore Fish Assemblages In Southeast, Alaska, Lia K. Domke

Fisheries

Nearshore marine ecosystems contain dynamic and complex submerged vegetated habitats that offer shelter and prey for juvenile, migratory, and residential species, including many commercial, subsistence, and recreationally important species. The efficacy of the nursery role, shelter, and source of prey of the nearshore is influenced by various abiotic and biotic forces and in this dissertation, we examine the influence of submerged vegetation type, presence of apex predators, and the seascape context on patterns of nearshore fish assemblages in southern Southeast Alaska. We found species-specific responses by juvenile salmon in the nearshore, with seasonality overwhelmingly driving juvenile salmon abundance in eelgrass …

Uncovering Patterns And Mechanisms Of Paralytic Shellfish Toxicity In Alaska's Geoduck Clam Fishery, Courtney E. Hart

Fisheries

This dissertation explores the patterns and mechanisms of paralytic shellfish toxicity in commercially harvested geoduck clams caused by the toxin-producing dinoflagellate Alexandrium catenella in Southeast Alaska. Alaska's commercial fishery for geoduck clams (Panopea generosa) is a small but lucrative fishery, with annual ex-vessel values averaging US $3.9 million (2010-2022). In recent years, the presence of paralytic shellfish toxins (PSTs) in clam tissue resulted in declines in fishery openings and harvest. PSTs can bioaccumulate in the tissues of filter feeders when A. catenella blooms in the spring and summer seasons. However, high levels of toxicity in geoduck clams occur sporadically during …

Model-Based Estimation Of Juvenile Salmon Spatial Ecology In The Eastern Bering Sea, Alaska, Lilian Hart

Fisheries

Quantitative descriptions of juvenile salmon spatial ecology during the marine phase of their lifecycle are needed to help direct conservation efforts and uncover latent relationships between juvenile salmon and their environment. The NOAA Fisheries Essential Fish Habitat (EFH) program contributes to the conservation of species in the marine waters off of the coast of Alaska by identifying areas of particular importance to reproduction and growth. Salmon EFH definitions have not yet been updated using the species distribution modeling approach taken most recently in defining Alaska groundfish and crab EFH. Current EFH definitions for Alaskan salmon are geographically broad, do not …

When Beavers Get Burned, Do Fish Get Fried? The Role Of Beavers To Mediate Wildfire Effects On Arctic Grayling In Boreal Alaska, William T. Samuel

Fisheries

Wildfire is a dominant natural disturbance process throughout boreal North America and fires are increasing in size, frequency, and severity. However, little is known about how wildfire affects boreal fish populations and aquatic habitat despite the substantial impacts of fire on ecosystem processes, and even less is known about how fire effects are mediated by species interactions. For example, North American Beavers (Castor canadensis) are affected by and can influence wildfire dynamics, and their engineering has complex effects on aquatic habitats. North American Beavers therefore have the potential to mediate wildfire effects on aquatic ecosystems and fish populations. Here I …