Digital Commons Network^™

Anaerobic Respiration Of Escherichia Coli In The Mouse Intestine, Shari A. Jones, Terri Gibson, Rosalie C. Maltby, Fatema Z. Chowdhury, Valley Stewart, Paul S. Cohen, Tyrrell Conway

Cell and Molecular Biology Faculty Publications

The intestine is inhabited by a large microbial community consisting primarily of anaerobes and, to a lesser extent, facultative anaerobes, such as Escherichia coli, which we have shown requires aerobic respiration to compete successfully in the mouse intestine (S. A. Jones et al., Infect. Immun. 75:4891-4899, 2007). If facultative anaerobes efficiently lower oxygen availability in the intestine, then their sustained growth must also depend on anaerobic metabolism. In support of this idea, mutants lacking nitrate reductase or fumarate reductase have extreme colonization defects. Here, we further explore the role of anaerobic respiration in colonization using the streptomycin-treated mouse model. We …

Genotype And Phenotypes Of An Intestine-Adapted Escherichia Coli K-12 Mutant Selected By Animal Passage For Superior Colonization, Andrew J. Fabich, Mary P. Leatham, Joe E. Grissom, Graham Wiley, Hongshing Lai, Fares Najar, Bruce A. Roe, Paul S. Cohen, Tyrrell Conway

Cell and Molecular Biology Faculty Publications

We previously isolated a spontaneous mutant of Escherichia coli K-12, strain MG1655, following passage through the streptomycin-treated mouse intestine, that has colonization traits superior to the wild-type parent strain (M. P. Leatham et al., Infect. Immun. 73:8039–8049, 2005). This intestine-adapted strain (E. coli MG1655*) grew faster on several different carbon sources than the wild type and was nonmotile due to deletion of the flhD gene. We now report the results of several high-throughput genomic analysis approaches to further characterize E. coli MG1655*. Whole-genome pyrosequencing did not reveal any changes on its genome, aside from the deletion at the flhDC …

Hlyu Is A Positive Regulator Of Hemolysin Expression In Vibrio Anguillarum, Ling Li, Xiangyu Mou, David R. Nelson

Cell and Molecular Biology Faculty Publications

The two hemolysin gene clusters previously identified in Vibrio anguillarum, the vah1 cluster and the rtxACHBDE cluster, are responsible for the hemolytic and cytotoxic activities of V. anguillarum in fish. In this study, we used degenerate PCR to identify a positive hemolysin regulatory gene, hlyU, from the unsequenced V. anguillarum genome. The hlyU gene of V. anguillarum encodes a 92-amino-acid protein and is highly homologous to other bacterial HlyU proteins. An hlyU mutant was constructed, which exhibited an ∼5-fold decrease in hemolytic activity on sheep blood agar with no statistically significant decrease in cytotoxicity of the wild-type strain. Complementation …

Significant Natural Product Biosynthetic Potential Of Actinorhizal Symbionts Of The Genus Frankia, As Revealed By Comparative Genomic And Proteomic Analyses, Daniel W. Udwary, Erin A. Gontang, Adam C. Jones, Carla S. Jones, Andrew W. Schultz, Jaclyn M. Winter, Jane Y. Yang, Nicholas Beauchemin, Todd L. Capson, Benjamin R. Clark, Eduardo Esquenazi, Alessandra S. Eustáquio, Kelle Freel, Lena Gerwick, William H. Gerwick, David Gonzalez, Wei-Ting Liu, Karla L. Malloy, Katherine N. Maloney, Markus Nett, Joshwana K. Nunnery, Kevin Penn, Alejandra Prieto-Davo, Thomas L. Simmons, Sara Weitz, Michael C. Wilson, Louis S. Tisa, Pieter C. Dorrestein, Bradley S. Moore

Biomedical and Pharmaceutical Sciences Faculty Publications

Bacteria of the genus Frankia are mycelium-forming actinomycetes that are found as nitrogen-fixing facultative symbionts of actinorhizal plants. Although soil-dwelling actinomycetes are well-known producers of bioactive compounds, the genus Frankia has largely gone uninvestigated for this potential. Bioinformatic analysis of the genome sequences of Frankia strains ACN14a, CcI3, and EAN1pec revealed an unexpected number of secondary metabolic biosynthesis gene clusters. Our analysis led to the identification of at least 65 biosynthetic gene clusters, the vast majority of which appear to be unique and for which products have not been observed or characterized. More than 25 secondary metabolite structures or structure …

Substituted Coumarin Derivatives: Synthesis And Evaluation Of Antiproliferative And Src Kinase Inhibitory Activities, Abha Kathuria, Sarah Jalal, Rakesh Tiwari, Amir Nasrolahi Shirazi, Shilpi Gupta, Shiv Kumar, Keykavous Parang, Sunil K. Sharma

Biomedical and Pharmaceutical Sciences Faculty Publications

Six classes of coumarin derivatives (i.e. 3-alkyl-4-methylcoumarins, pyranocoumarins, coumarin carboxamides, quaternary ammonium coumarins, 7-aminocoumarins, and 4-aminocoumarins) were synthesized and evaluated for inhibition of cell proliferation of colon adenocarcinoma (HT-29), breast carcinoma (MDA-MB-468 or MCF-7), and human ovarian adenocarcinoma (SK-OV-3) cells. C-3-Alkyl substituted analogs of 4-methylcoumarins and pyranocoumarins, 5 and 6, inhibited the cell proliferation of MDA-MB-468 and SK-OV-3 cells by 53-74%, while 3-decyl substituted pyranocoumarin 10 and triethyl substituted quaternary ammonium coumarin derivative 29 inhibited the cell proliferation of HT-29 and SK-OV-3 cells by 63-72% at a concentration of 50 μM. Among all the compounds studied, C-3 decyl substituted …

Cytotoxicity Of Aporphines In Human Colon Cancer Cell Lines Hct-116 And Caco-2: An Sar Study, Shashikanth Ponnala, Sandeep Chaudhary, Antonio González-Sarrias, Navindra P. Seeram, Wayne W. Harding

Biomedical and Pharmaceutical Sciences Faculty Publications

A series of synthetic aporphine derivatives structurally related to domesticine and nantenine (ring A, N6 and ring C truncated analogs), was evaluated in MTS cytotoxicity assays against the human colon cancer cell lines, HCT-116 and Caco-2. In general, the C1 position of ring A is tolerant of alkoxy substituents as well as a benzoyl ester functionality. Other modifications evaluated resulted in a decrease in cytotoxic activity. The most potent compounds identified had IC₅₀ values in the range 23–38 μM, comparable to the known cytotoxic agent, etoposide.

Inhibition Of Multi-Drug Resistant Hiv-1 Reverse Transcriptase By Nucleoside Β-Triphosphates, Chandravanu Dash, Yousef Ahmadibeni, Michael J. Hanley, Jui Pandhare, Mathias Gotte, Stuart F.J. Le Grice, Keykavous Parang

Biomedical and Pharmaceutical Sciences Faculty Publications

Despite the success of potent reverse transcriptase (RT) inhibitors against human immunodeficiency virus type 1 (HIV-1) in combination regimens, the development of drug resistant RTs constitutes a major hurdle for the long-term efficacy of current antiretroviral therapy. Nucleoside β-triphosphate analogs of adenosine and nucleoside reverse transcriptase inhibitors (NRTIs) (3′-azido-2′,3′-dideoxythymidine (AZT), 3′-fluoro-2′,3′-dideoxythymidine (FLT), and 2′,3′-didehydro-2′,3′-dideoxythymidine (d4T)) were synthesized and their inhibitory activities were evaluated against wild-type and multidrug resistant HIV-1 RTs. Adenosine β-triphosphate (1) and AZT β-triphosphate (2) completely inhibited the DNA polymerase activity of wild type, the NRTI multi resistant, and nonnucleoside RT inhibitors (NNRTI) resistant …

Monoamine Neurotransmitters As Substrates For Novel Tick Sulfotransferases, Homology Modeling, Molecular Docking, And Enzyme Kinetics, Emine Bihter Yalcin, Hubert Strangl, Sivakamasundari Pichu, Thomas N. Mather, Roberta S. King

Biomedical and Pharmaceutical Sciences Faculty Publications

Blacklegged ticks (Ixodes scapularis) transmit the causative agent of Lyme disease in the Northeastern United States. Current research focuses on elucidating biochemical pathways that may be disrupted to prevent pathogen transmission, thereby preventing disease. Genome screening reported transcripts coding for two putative sulfotransferases in whole tick extracts of the nymphal and larval stages. Sulfotransferases are known to sulfonate phenolic and alcoholic receptor agonists such as 17β-estradiol, thereby inactivating the receptor ligands. We used bioinformatic approaches to predict substrates for Ixosc Sult 1 and Ixosc Sult 2 and tested the predictions with biochemical assays. Homology models of 3D protein …

Constitutive Immune Function In European Starlings, Sturnus Vulgaris, Is Decreased Immediately After An Endurance Flight In A Wind Tunnel, Silke Nebel, Ulf Bauchinger, Deborah M. Buehler, Lillie A. Langlois, Michelle Boyles, Alexander R. Gerson, Edwin R. Price, Scott R. Mcwilliams, Christopher Guglielmo

Natural Resources Science Faculty Publications

Life-history theory predicts that animals face a trade-off in energy allocation between performing strenuous exercise, such as migratory flight, and mounting an immune response. We experimentally tested this prediction by studying immune function in European starlings, Sturnus vulgaris, flown in a wind tunnel. Specifically, we predicted that constitutive immune function decreases in response to training and, additionally, in response to immediate exercise. We compared constitutive immune function among three groups: (1) ‘untrained’ birds that were kept in cages and were not flown; (2) ‘trained’ birds that received flight training over a 15 day period and performed a 1-4 h …

Become The Change Newsletter For January 2011, Center For Nonviolence And Peace Studies

Center for Nonviolence & Peace Studies

The January 2011 issue of the Center for Nonviolence and Peace Studies newsletter, Become the Change, is a periodical with articles written by faculty, ongoing research projects, upcoming course offerings and Center events.

Aboard Gso: A Newsletter For Alumni And Friends Of The University Of Rhode Island’S Graduate School Of Oceanography For Winter 2011, Uri Graduate School Of Oceanography

Graduate School of Oceanography Publications

The Winter 2011 (Volume 9, Issue 2) issue of Aboard GSO: A Newsletter for Alumni and Friends of the University of Rhode Island’s Graduate School of Oceanography, a periodical about GSO events, faculty research and essays by alumni.

Aboard Gso: A Newsletter For Alumni And Friends Of The University Of Rhode Island’S Graduate School Of Oceanography For Spring 2011, Uri Graduate School Of Oceanography

Graduate School of Oceanography Publications

The Spring 2011 (Volume 9, Issue 1) issue of Aboard GSO: A Newsletter for Alumni and Friends of the University of Rhode Island’s Graduate School of Oceanography, a periodical about GSO events, faculty research and essays by alumni.

Molecular Characterization Of Novel Sulfotransferases From The Tick, Ixodes Scapularis, Sivakamasundari Pichu, Emine Bihter Yalcin, José Mc Ribeiro, Roberta S. King, Thomas N. Mather

Biomedical and Pharmaceutical Sciences Faculty Publications

Background: Ixodes scapularis, commonly known as the blacklegged or deer tick, is the main vector of Lyme disease in the United States. Recent progress in transcriptome research has uncovered hundreds of different proteins expressed in the salivary glands of hard ticks, the majority of which have no known function, and include many novel protein families. We recently identified transcripts coding for two putative cytosolic sulfotransferases in these ticks which recognized phenolic monoamines as their substrates. In this current study, we characterize the genetic expression of these two cytosolic sulfotransferases throughout the tick life cycle as well as the …

Dynamics Of A Two-Dimensional System Of Rational Difference Equations Of Leslie--Gower Type, S. Kalabušić, Mustafa Kulenović, E. Pilav

Mathematics Faculty Publications

We investigate global dynamics of the following systems of difference equations

[Mathematical equations cannot be displayed here, refer to PDF]

where the parameters α ₁, β ₁, A ₁, γ ₂, A ₂, B ₂ are positive numbers, and the initial conditions x ₀ and y ₀ are arbitrary nonnegative numbers. We show that this system has rich dynamics which depends on the region of parametric space. We show that the basins of attractions of different locally asymptotically stable equilibrium points or non-hyperbolic equilibrium points are separated by the global stable manifolds of either saddle …

Adherence To Dual-Method Contraceptive Use, Jeffrey F. Peipert, Qiuhong Zhao, Laura Meints, Benjamin J. Peipert, Colleen A. Redding, Jenifer E. Allsworth

Cancer Prevention Research Center Faculty Publications

Background: Patient characteristics associated with adherence to dual-method contraceptive use are not known.

Study Design: Project PROTECT was a 24-month-long randomized trial designed to promote the use of dual methods of contraception using an individualized computer-based intervention or enhanced standard care counseling intervention. We analyzed 463 women with follow-up data and examined sustained dual-method use (reported at 2+ interviews).

Results: While 32% initiated dual-method contraceptive use, only 9% reported sustained use. Education increased (RR_adj=4.42; 95% confidence interval [CI] 1.19–16.42), substance abuse decreased (adjusted relative risk [RR_adj]=0.49; 95% CI 0.24–0.97), no contraceptive use at baseline decreased (RR …

Roles Of Carboxyl Groups In The Transmembrane Insertion Of Peptides, Francisco N. Barrera, Dhammika Weerakkody, Michael Anderson, Oleg A. Andreev, Yana K. Reshetnyak, Donald M. Engelman

Physics Faculty Publications

We have used pHLIP® [pH (low) insertion peptide] to study the roles of carboxyl groups in transmembrane (TM) peptide insertion. pHLIP binds to the surface of a lipid bilayer as a disordered peptide at neutral pH; when the pH is lowered, it inserts across the membrane to form a TM helix. Peptide insertion is reversed when the pH is raised above the characteristic pK_a (6.0). A key event that facilitates membrane insertion is the protonation of aspartic acid (Asp) and/or glutamic acid (Glu) residues, since their negatively charged side chains hinder membrane insertion at …

Tuning A Polar Molecule For Selective Cytoplasmic Delivery By A Ph (Low) Insertion Peptide, Dayanjali Wijesinghe, Donald M. Engelman, Oleg A. Andreev, Yana K. Reshetnyak

Physics Faculty Publications

Drug molecules are typically hydrophobic and small in order to traverse membranes to reach cytoplasmic targets, but we have discovered that more polar molecules can be delivered across membranes using water-soluble, moderately hydrophobic membrane peptides of the pHLIP (pH low insertion peptide) family. Delivery of polar cargo molecules could expand the chemical landscape for pharmacological agents that have useful activity but are too polar by normal drug criteria. The spontaneous insertion and folding of the pHLIP peptide across a lipid bilayer seeks a free energy minimum, and insertion is accompanied by a release of energy that can be used to …

Measuring Tumor Aggressiveness And Targeting Metastatic Lesions With Fluorescent Phlip, Yana K. Reshetnyak, Lan Yao, Sida Zheng, Sergey Kuznetsov, Donald M. Engelman, Oleg A. Andreev

Physics Faculty Publications

Purpose: Malignant cancer foci develop acidic extracellular environments. Mild acidic conditions trigger insertion and folding of the pH (low) insertion peptide (pHLIP^TM) across a cellular membrane, enabling targeting of such lesions.

Procedures: We employed optical imaging to follow targeting by fluorescent pHLIP given i.v. in mice. For visualization, Cy5.5 and Alexa750 were covalently attached to the N terminus of pHLIP, which stays outside of a cell membrane after transmembrane insertion.

Results: We demonstrate that pHLIP targets: (a) tumors of different origins established by subcutaneous injection of cancer cells, (b) spontaneous prostate tumors in TRAMP mice and (c) metastatic …

Letters To Silent Teachers In Tzu Chi Medical School: A Spiritual Interaction, Guo-Ming Chen, Chien Chang, Tong Yu

Communication Studies Faculty Publications

This article examines the spiritual communication between medical students and the donated dead body they anatomized, referred to as the silent teacher. Data were obtained from the medical school of Tzu Chi University in Taiwan, where students are required to write a letter to the silent teacher at the end of the semester after they have anatomized the body. The school has collected and published a total of 89 letters from 1996 to 2001. This article content analyzes all the 89 letters published and draws common themes from them. Based on the results of this content analysis, we have …

Synthesis And Anti-Hiv Activities Of Bis-(Cyclosaligenyl) Pronucleotides Derivatives Of 3′-Fluoro-3′-Deoxythymidine And 3′-Azido-3′-Deoxythymidine, Yousef Ahmadibeni, Rakesh Tiwari, Chelsie Swepson, Jui Pandhare, Chandravanu Dash, Gustavo F. Doncel, Keykavous Parang

Biomedical and Pharmaceutical Sciences Faculty Publications

Anti-HIV nucleoside monophosphates have limited cellular uptake due to the presence of negatively-charged phosphate group. Bis-(cycloSaligenyl) derivatives containing two anti-HIV nucleosides, 3′-fluoro-3′-deoxythymidine (FLT) and 3′-azido-3′-deoxythymidine (AZT) were synthesized to increase intracellular delivery of nucleoside monophosphates. 2,5-Bis(hydroxymethylene)benzene-1,4-diol was selected as a monocyclic bidentate scaffold and synthesized by three different methods from bis(hydroxymethylene)cyclohexan-1,4-diene-1,4-diol, or diethyl 2,5-dihydroxyterephthalate. The reaction of the tetraol with diisopropylphosphoramidous dichloride in the presence of 2,6-lutidine, followed by conjugation reactions with nucleosides (i.e., FLT and AZT) and oxidation afforded symmetrical and unsymmetrical bis-(cycloSaligenyl) diphosphate triester products, AZT–AZT, FLT–FLT, and FLT–AZT conjugates, in 63–74% overall yields …

On Design And Implementation Of Neural-Machine Interface For Artificial Legs, Xiaorong Zhang, Yuhong Liu, Fan Zhang, Jin Ren, Yan (Lindsay) Sun, Qing Yang, He Huang

Electrical, Computer, and Biomedical Engineering Faculty Publications

The quality-of-life of leg amputees can be improved dramatically by using a cyber-physical system (CPS) that controls artificial legs based on neural signals representing amputees' intended movements. The key to the CPS is the neural-machine interface (NMI) that senses electromyographic (EMG) signals to make control decisions. This paper presents a design and implementation of a novel NMI using an embedded computer system to collect neural signals from a physical system-a leg amputee, provide adequate computational capability to interpret such signals, and make decisions to identify user's intent for prostheses control in real time. A new deciphering algorithm, composed of an …

A Special Purpose Embedded System For Neural Machine Interface For Artificial Legs, Xiaorong Zhang, He Huang, Qing Yang

Electrical, Computer, and Biomedical Engineering Faculty Publications

This paper presents a design and implementation of a neural-machine interface (NMI) for artificial legs that can decode amputee's intended movement in real time. The newly designed NMI integrates an FPGA chip for fast processing and a microcontroller unit (MCU) with multiple on-chip analog-to-digital converters (ADCs) for real-time data sampling. The resulting embedded system is able to sample in real time 12 EMG signals and 6 mechanical signals and execute a special complex phase-dependent classifier for accurate recognition of the user's intended locomotion modes. The implementation and evaluation are based on Altera's Stratix III 3S150 FPGA device coupled with Freescale's …

Multicomponent Folate-Targeted Magnetoliposomes: Design, Characterization, And Cellular Uptake, Geoffrey D. Bothun, Alline Lelis, Yanjing Chen, Kyle Scully, Linnea E. Anderson, Matthew A. Stoner

Chemical, Biomolecular, and Materials Engineering Faculty Publications

Folate-targeted cationic magnetoliposomes (FTMLs) have been prepared with coencapsulated doxorubicin (DOX) and anionic superparamagnetic iron oxide (SPIO) nanoparticles (NPs) with 5 nm γ-Fe₂O₃ cores and 16 nm hydrodynamic diameters. NP encapsulation (89%) was confirmed by cryogenic transmission electron microscopy (TEM), and the presence of the oppositely charged NPs did not cause liposome aggregation. The FTMLs had an average diameter of 174 ± 53 nm and existed as unilamellar and cup-shaped liposomes, which was attributed to dissimilar lipid packing parameters and the presence of PEG-lipids. A 3-fold increase in DOX release was achieved over 2 hours when the …

An Analysis Of The Capacity Of Coastal Management Practitioners To Develop Coastal Ecosystem‐Based Management Plans, Tiffany Catherine Smythe

Open Access Dissertations

Ecosystem‐based management (EBM) is an integrated, collaborative resource management strategy that is widely touted as the preferred approach to coastal and environmental management. Yet coastal management decisions largely occur through a fragmented system of governance, whereby coastal management practitioners act somewhat autonomously to make land‐ and water‐use decisions that can have tremendous impacts on entire ecosystems. There are relatively few examples of coastal ecosystem‐based management in practice; one possible reason is that a truly EBM approach, considering both the social and ecological aspects of an ecosystem, places extreme demands on coastal management practitioners. To effectively develop coastal EBM plans, practitioners …

The Use Of Omega-3 Fatty Acids In Mental Illness, Jessica L. Gören, T. Tewksbury

Pharmacy Practice and Clinical Research Faculty Publications

Purpose: This article will summarize the current evidence on the effects of omega-3 fatty acids on prevention and treatment of mental illness. Background: Omega-3 fatty acids are involved in many physiologic processes. Since they cannot be made de novo in the body, they are considered essential nutrients. As the Western diet evolved, dietary intake of fatty acids has shifted to increased omega-6 fatty acids and decreased omega-3 fatty acids intake. These changes have been correlated with numerous differences in prevalence and course of mental illnesses. Methods: A MEDLINE search from 1966 to December 2010 was completed to …

Instabilities In An Internal Solitary-Like Wave On The Oregon Shelf, Levin G. Lamb, David M. Farmer

Graduate School of Oceanography Faculty Publications

Observations of internal solitary-like waves (ISWs) on the Oregon Shelf suggest the presence of Kelvin–Helmholtz billows in the pycnocline and larger-scale overturns at the back of the wave above the pycnocline. Numerical simulations designed to explore the mechanisms responsible for these features in one particular wave reveal that shear instabilities occur when (i) the minimum Richardson number Ri in the pycnocline is less than about 0.1; (ii) L_x/λ > 0.8, where L_x is the length of the unstable region with Ri < 0.25 and λ is a half wavelength of the wave; and (iii) a linear spatial stability analysis predicts …

Biodiversity And Ecosystem Function In The Gulf Of Maine: Pattern And Role Of Zooplankton And Pelagic Nekton, Catherine L. Johnson, Jeffrey A. Runge, K. Alexandra Curtis, Edward G. Durbin, Jonathan A. Hare, Lewis S. Incze, Jason S. Link, Gary D. Melvin, Todd D. O'Brien, Lou Van Guelpen

Graduate School of Oceanography Faculty Publications

This paper forms part of a broader overview of biodiversity of marine life in the Gulf of Maine area (GoMA), facilitated by the GoMA Census of Marine Life program. It synthesizes current data on species diversity of zooplankton and pelagic nekton, including compilation of observed species and descriptions of seasonal, regional and cross-shelf diversity patterns. Zooplankton diversity in the GoMA is characterized by spatial differences in community composition among the neritic environment, the coastal shelf, and deep offshore waters. Copepod diversity increased with depth on the Scotian Shelf. On the coastal shelf of the western Gulf of Maine, the number …

An International Quiet Ocean Experiment, Ian L. Boyd, George Frisk, Ed Urban, Peter Tyack, Jesse Ausubel, Sophie Seeyave, Doug Cato, Brandon Southall, Michael Weise, Rex Andrew, Tomonari Akamatsu, René Dekeling, Christine Erbe, David Farmer, Roger Gentry, Tom Gross, Anthony Hawkins, Fenghua Li, Kathy Metcalf, James H. Miller, David Moretti, Cristian Rodrigo, Tomio Shinke

Graduate School of Oceanography Faculty Publications

The effect of noise on marine life is one of the big unknowns of current marine science. Considerable evidence exists that the human contribution to ocean noise has increased during the past few decades: human noise has become the dominant component of marine noise in some regions, and noise is directly correlated with the increasing industrialization of the ocean. Sound is an important factor in the lives of many marine organisms, and theory and increasing observations suggest that human noise could be approaching levels at which negative effects on marine life may be occurring. Certain species already show symptoms of …

Evidence For Aggregation And Export Of Cyanobacteria And Nano-Eukaryotes From The Sargasso Sea Euphotic Zone, M. W. Lomas, S. Bradley Moran

Graduate School of Oceanography Faculty Publications

Pico-plankton and nano-plankton are generally thought to represent a negligible fraction of the total particulate organic carbon (POC) export flux in oligotrophic gyres due to their small size, slow individual sinking rates, and tight grazer control that leads to high rates of recycling in the euphotic zone. Based upon recent inverse modeling and network analysis however, it has been hypothesized that pico-plankton, including the cyanobacteria Synechococcus and Prochlorococcus, and nano-plankton contribute significantly to POC export, via formation and gravitational settling of aggregates and/or consumption of those aggregates by mesozooplankton, in proportion to their contribution to net primary production. This …

Sustained Monitoring Of The Southern Ocean At Drake Passage: Past Achievements And Future Priorities, Michael P. Meredith, Philip L. Woodworth, Teresa K. Chereskin, David P. Marshall, Lesley C. Allison, Grant R. Bigg, Kathleen A. Donohue, Karen J. Heywood, Chris W. Hughes, Angela Hibbert, Andrew Mcc. Hogg, Helen L. Johnson, Loic Jullion, Brian A. King, Harry Leach, Yueng-Djern Lenn, Miguel A. Morales Maqueda, David R. Munday, Alberto C. Naveira Garabato, Christine Provost, Jean-Baptiste Sallée, Janet Sprintall

Graduate School of Oceanography Faculty Publications

Drake Passage is the narrowest constriction of the Antarctic Circumpolar Current (ACC) in the Southern Ocean, with implications for global ocean circulation and climate. We review the long‐term sustained monitoring programs that have been conducted at Drake Passage, dating back to the early part of the twentieth century. Attention is drawn to numerous breakthroughs that have been made from these programs, including (1) the first determinations of the complex ACC structure and early quantifications of its transport; (2) realization that the ACC transport is remarkably steady over interannual and longer periods, and a growing understanding of the processes responsible for …