Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons™

Open Access. Powered by Scholars. Published by Universities.®

2008

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 3571 - 3600 of 3985

Full-Text Articles in Life Sciences

Estimation Of Submarine Groundwater Discharge From Bulk Ground Electrical Conductivity Measurements, Thomas Stieglitz, John Rapaglia, Henry Bokuniewicz Jan 2008

Estimation Of Submarine Groundwater Discharge From Bulk Ground Electrical Conductivity Measurements, Thomas Stieglitz, John Rapaglia, Henry Bokuniewicz

Biology Faculty Publications

The utility of bulk ground conductivity (BGC) measurements in the estimation of submarine groundwater discharge (SGD) was investigated at four sites covering a range of hydrogeological settings, namely Cockburn Sound (Australia); Shelter Island (USA); Ubatuba Bay (Brazil) and Flic-en-Flac Bay (Mauritius). At each of the sites, BGC was surveyed in the intertidal zone, and seepage meters were used for direct measurements of SGD flow rates. In the presence of detectable salinity gradients in the sediment, a negative correlation between SGD and BGC was recorded. The correlation is site-specific and is dependent on both the type of sediment and the mixing …


Project Limulus: What Long-Term Mark/Recapture Studies Reveal About Horseshow Crab Population Dynamics In Long Island Sound, Mark Beekey, Jennifer Mattei Jan 2008

Project Limulus: What Long-Term Mark/Recapture Studies Reveal About Horseshow Crab Population Dynamics In Long Island Sound, Mark Beekey, Jennifer Mattei

Biology Faculty Publications

Project Limulus is a long-term study of the population dynamics of the horseshoe crab population in Long Island Sound (LIS). We have tagged over 20,000 spawning adults from >20 beaches ranging from Greenwich to Stonington, CT since 1997. Cumulative recapture rates have reached 9%. On average 90% of the crabs are recaptured within a few miles of their original tag site within the first season. Between seasons, on average, 45% of crabs are recaptured within the same locality of where they were tagged. Of all recaptures, 99% of recaptured individuals are found within LIS. This past year we expanded the …


Comparative Diet Of Three Sympatric Sceloporus In The Semiarid Zapotitlan Valley, Mexico, V. Hugo Serrano-Cardozo, J. A. Lemos-Espinal, Geoffrey R. Smith Jan 2008

Comparative Diet Of Three Sympatric Sceloporus In The Semiarid Zapotitlan Valley, Mexico, V. Hugo Serrano-Cardozo, J. A. Lemos-Espinal, Geoffrey R. Smith

Faculty Publications

No abstract provided.


State Of The Fisheries Report 2007/08, Warrick J. Fletcher, K. Santoro Jan 2008

State Of The Fisheries Report 2007/08, Warrick J. Fletcher, K. Santoro

Status Reports of the Fisheries and Aquatic Resources

The State of the Fisheries Report is published annually to provide a detailed level of reporting on the management of fish stocks and their environment undertaken by the Department of Fisheries. A summary report from this document is included in the Department’s Annual Report to Parliament, which includes the Department’s nonfinancial (fishery) performance indicators. The Annual Report is no longer printed but is available through the Department’s website (www.fish.wa.gov.au).


Mechanical Abrasion And Electroporation In The Transformation Of Intact Pleurotus Ostreatus Hyphæ And Nutrient-Dependant Resistance To Hygromycin B, Alexander Cordesman Jan 2008

Mechanical Abrasion And Electroporation In The Transformation Of Intact Pleurotus Ostreatus Hyphæ And Nutrient-Dependant Resistance To Hygromycin B, Alexander Cordesman

Theses and Dissertations

ABSTRACT 1: Abrasive treatment and subsequent electroporation of the basidiomycete Pleurotus ostreatus in a hypertonic buffer was investigated as a potential method of transforming of intact hyphæ. Mycelia, which are not capable of being transformed via electroporation due to interference by the cell wall, were abraded in an attempt to mechanically degrade the cell wall prior to electroporation. An electroporation field strength of 12,500 V/cm for 500 μs to 1.25 ms was found to be optimal based upon mortality effects. A 32 μm carborundum abrasive was initially evaluated but was quickly found to be inappropriately large so a corundum abrasive …


Cold Atmospheric Pressure Air Plasma Jet For Medical Applications, Juergen Friedrich Kolb, A.-A H. Mohamed, R. O. Price, R. J. Swanson, A. Bowman, R. L. Chiavarini, Michael W. Stacey Jan 2008

Cold Atmospheric Pressure Air Plasma Jet For Medical Applications, Juergen Friedrich Kolb, A.-A H. Mohamed, R. O. Price, R. J. Swanson, A. Bowman, R. L. Chiavarini, Michael W. Stacey

Bioelectrics Publications

By flowing atmospheric pressure air through a direct current powered microhollow cathode discharge, we were able to generate a 2 cm long plasma jet. With increasing flow rate, the flow becomes turbulent and temperatures of the jet are reduced to values close to room temperature. Utilizing the jet, yeast grown on agar can be eradicated with a treatment of only a few seconds. Conversely, animal studies show no skin damage even with exposures ten times longer than needed for pathogen extermination. This cold plasma jet provides an effective mode of treatment for yeast infections of the skin.


Modulation Of Fast-Inactivating Potassium Channels By Accessory Subunits And Fatty Acids : A Role For Calcium?, Michelle M. Drzewiecki Jan 2008

Modulation Of Fast-Inactivating Potassium Channels By Accessory Subunits And Fatty Acids : A Role For Calcium?, Michelle M. Drzewiecki

Honors Theses

Potassium channel interacting proteins (KChIPs) co-assemble with Kv4 a subunits to form native complexes that encode considerable components of neuronal somatodendritic A- type K+current (Is,J in neurons, and transient outward current (ho) in cardiac myocytes. The binding of KChIPs to the cytoplasmic N-termini of Kv4 a subunits enhances surface expression by facilitating intracellular trafficking, stimulates subunit assembly, and regulates the functional gating properties of Kv4 channels. KChIPs, like many other neuronal calcium sensor proteins, contain four EF-hand calcium binding sites; two of which (EF-3 and 4) have particularly high affinity for calcium. Because Ca2+ is an important signaling molecule for …


The Exploration Of Novel Symbiotic Bacteria That May Have Influential Roles In Sponge Life History, Brittany E. West Jan 2008

The Exploration Of Novel Symbiotic Bacteria That May Have Influential Roles In Sponge Life History, Brittany E. West

Honors Theses

Sponges produce an impressive variety of secondary metabolites that perform a variety of ecological functions. Many marine sponges even harbor diverse carotenoid compounds, an unusual class of secondary metabolites that animals are incapable of producing. Furthermore, sponges serve as hosts to an astonishingly diverse microbial community that can occupy up to sixty percent of a sponge's biomass. Our research ultimately hopes to link microbial species to the production of secondary compounds, like carotenoids, and to assess the ecological role of such compounds and their effect on sponge life history strategy. This study describes the ecological distribution of two species of …


Otolith Chemistry Indicates Population Structuring By The Antarctic Circumpolar Current, Julian R. Ashford, Cynthia M. Jones, Eileen E. Hofmann, Inigo Everson, Carlos A. Moreno, Guy Duhamel, Richard Williams Jan 2008

Otolith Chemistry Indicates Population Structuring By The Antarctic Circumpolar Current, Julian R. Ashford, Cynthia M. Jones, Eileen E. Hofmann, Inigo Everson, Carlos A. Moreno, Guy Duhamel, Richard Williams

CCPO Publications

Large-scale transport of seawater in ocean currents may generate spatially complex population structure through the advection of life stages of marine fish species. To test this, we compared the chemistry of otolith nuclei from Patagonian toothfish (Dissostichus eleginoides), presently managed as spatially discrete Populations corresponding to fishing management areas along the Antarctic Circumpolar Current (ACC), which transports water eastward around the Southern Ocean. The chemistry of otolith nuclei, laid down during early life, differed significantly between fishing areas Off South America and the Antarctic and between some Antarctic areas. However, we found significant discrepancies from expectation for a …


A Modelling Study Of Developmental Stage And Environmental Variability Effects On Copepod Foraging, Jerry D. Wiggert, Eileen E. Hofmann, Gustav-Adolf Paffenhöfer Jan 2008

A Modelling Study Of Developmental Stage And Environmental Variability Effects On Copepod Foraging, Jerry D. Wiggert, Eileen E. Hofmann, Gustav-Adolf Paffenhöfer

CCPO Publications

We used a stochastic Lagrangian model to study how behaviour contributes to copepod grazing success. The model simulates distinct foraging behaviours of Clausocalanus furcatus, Paracalanus aculeatus, and Oithona plumifera. Three sets of simulations were performed to investigate the effects of (a) prey-size preference; (b) variation in prey-size spectra; and (c) turbulence intensity on these species’ grazing rates. The size preference simulations demonstrate that, compared with copepodites, mature females have cell ingestion rates that are an order of magnitude lower, while carbon uptake is reduced by 35%. A prey spectrum that is skewed towards cells ,<6 >μm promotes copepodite …


Physical And In Silico Approaches Identify Dna-Pk In A Tax Dna-Damage Response Interactome, Emad Ramadan, Michael Ward, Xin Guo, Sarah S. Durkin, Adam Sawyer, Marcelo Vilela, Christopher Osgood, Alex Pothen, Oliver J. Semmes Jan 2008

Physical And In Silico Approaches Identify Dna-Pk In A Tax Dna-Damage Response Interactome, Emad Ramadan, Michael Ward, Xin Guo, Sarah S. Durkin, Adam Sawyer, Marcelo Vilela, Christopher Osgood, Alex Pothen, Oliver J. Semmes

Biological Sciences Faculty Publications

Background: We have initiated an effort to exhaustively map interactions between HTLV-1 Tax and host cellular proteins. The resulting Tax interactome will have significant utility toward defining new and understanding known activities of this important viral protein. In addition, the completion of a full Tax interactome will also help shed light upon the functional consequences of these myriad Tax activities. The physical mapping process involved the affinity isolation of Tax complexes followed by sequence identification using tandem mass spectrometry. To date we have mapped 250 cellular components within this interactome. Here we present our approach to prioritizing these interactions via …


Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins Jan 2008

Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins

OES Faculty Publications

We examined the physiological responses of steady-state iron (Fe)-replete and Fe-limited cultures of the biogeochemically critical marine unicellular diazotrophic cyanobacterium Crocosphaera at glacial (19 Pa; 190 ppm), current (39 Pa; 380 ppm), and projected year 2100 (76 Pa; 750 ppm) CO2 levels. Rates of N2 and CO2 fixation and growth increased in step with increasing partial pressure of CO2 (pCO2), but only under Fe- replete conditions. N2) and carbon fixation rates at 75 Pa CO2 were 1.4-1.8-fold and 1.2-2.0-fold higher, respectively, relative to those at present day and glacial pCO2 …


Seasonal Variation In The Physical Characteristics Of The Copepod Calanus Finmarchicus (Gunnerus) Along The North Atlantic, A. A. Yusuf, L. Webster Jan 2008

Seasonal Variation In The Physical Characteristics Of The Copepod Calanus Finmarchicus (Gunnerus) Along The North Atlantic, A. A. Yusuf, L. Webster

All Peer-Reviewed Publications

Physical oceanographic changes such as the North Atlantic Oscillation, which manifested in the 1990s, are said to affect the seasonal/stage dependent, vertical migrations and life cycle of Calanus finmarchicus. C4-C6 stages of C. finmarchicus collected during spring and summer in 2002 from the Irminger Sea, Greenland Sea, Iceland shelf and the Raykjanes Ridge were analysed microscopically for their prosome and total body lengths and gravimetrically for dry weights. Dry weight ranged from 60 μg individual-1 in C4 to 326.6 μg individual-1 in C6 stages. Total body lengths showed an increase with sample stage and season (2.10 mm in spring C4 …


Food And Nutrient Intake And Attitudes Among Disadvantaged Groups On The Island Of Ireland: Summary Report, John Kearney, Daniel Mccarthy, Sarah Burke, Barbara Knox, Maria Barton Jan 2008

Food And Nutrient Intake And Attitudes Among Disadvantaged Groups On The Island Of Ireland: Summary Report, John Kearney, Daniel Mccarthy, Sarah Burke, Barbara Knox, Maria Barton

Reports

No abstract provided.


Comparative In Vitro Cytotoxicity Study Of Silver Nanoparticle On Two Mammalian Cell Lines, Gordon Chambers, Sanchali Mukherjee, Alan Casey, Niall Ó Claonadh Jan 2008

Comparative In Vitro Cytotoxicity Study Of Silver Nanoparticle On Two Mammalian Cell Lines, Gordon Chambers, Sanchali Mukherjee, Alan Casey, Niall Ó Claonadh

Articles

In this study the cytotoxic effect of commercially available silver (Ag) nanoparticle was evaluated using human dermal and cervical cancer cell lines. Prior to the cellular studies a full particle size characterisation was carried out using Dynamic Light Scattering (DLS), Transmission Electron Microscopy and Scanning Electron Microscopy in distilled water and cell culture media. The Zeta Potential (ZP)associated with the Ag nanoparticle was also determined in order to assess its stability in the solutions and its possible interaction with the media. The DLS and ZP study have suggested interaction of Ag nanoparticles with the media, which can lead to secondary …


Poverty, Diet And Health Behaviours: A Quantitative And Qualitative Study Among Young Urbanised Women., Daniel Mccartney Jan 2008

Poverty, Diet And Health Behaviours: A Quantitative And Qualitative Study Among Young Urbanised Women., Daniel Mccartney

Doctoral

Demographic, socio-economic, attitudinal, dietary, health behavioural and anthropometric data were collected from 221 “disadvantaged” and 74 “advantaged” women aged 18-35 years across Dublin, according to the provisions of a novel socio-economic sampling frame. Internal and external validation techniques established the dietary assessment method of choice and identified “valid” dietary reporters (n=216, 153 disadvantaged, 63 advantaged) among this sample. Five qualitative focus groups (n=5-8 per group) were also conducted among disadvantaged women to examine their diet and health behaviour choices. Lower intakes of fruit and vegetables (172g/d vs. 405g/d, p


Beyond The Debate: Exploring The Underlying Values And Assumptions Of Biodiversity Conservation In Protected Areas, Leon-Charl Malan Jan 2008

Beyond The Debate: Exploring The Underlying Values And Assumptions Of Biodiversity Conservation In Protected Areas, Leon-Charl Malan

Antioch University Dissertations & Theses

This dissertation examines the current disagreement among scientists and scholars about best practices for biodiversity conservation in protected areas. There is no clear consensus among the scientific community about the most effective approach to conserve biodiversity and several conflicting positions form part of an ongoing debate in the field. Most disagreements and conflicts are based on differences in the underlying values and assumptions of the parties involved in the conflict. The more we know and understand those underlying values, the more constructive the dialog, and the more likely acceptable policy decisions will be developed. This study, presented in three parts, …


Connecting With Nature Through Land Use Decision Making, Cathy Setterlin Jan 2008

Connecting With Nature Through Land Use Decision Making, Cathy Setterlin

Antioch University Dissertations & Theses

This narrative inquiry, which draws on my experience as a land use decision maker, environmental educator, and scholar, examines the complexities of our human-nature relationship as we use and protect the life of the land in local communities. I began this research by interviewing seventeen land use decision makers representing a range of land use perspectives in New Milford, Connecticut, focusing on their views of land as a living community, their connections to land, and their sense of duty and responsibility.

Their responses led me to further inquiry and drew me into a process that transformed my views of both …


The Metastasis Suppressor Nm23-H1 Is Required For Dna Repair, Mengmeng Yang Jan 2008

The Metastasis Suppressor Nm23-H1 Is Required For Dna Repair, Mengmeng Yang

University of Kentucky Doctoral Dissertations

NM23-H1 represents the first identified metastasis suppressor, exhibiting reduced expression in breast carcinoma and melanoma, and an ability to inhibit metastatic growth without significant impact on the transformed phenotype. Although its molecular mechanism of action is not fully understood, NM23-H1 possesses at least three enzymatic activities that may mediate metastasis suppressor function. It catalyzes nucleoside diphosphate kinase (NDPK) activity, as well as protein histidine kinase and 3’-5’ exonuclease activities. As 3’-5’ exonucleases are generally required for maintenance of genomic integrity, this activity represents a plausible mediator to underlie the metastasis suppressor function of NM23-H1 protein. To investigate the relevant activity …


Colloid Mediated Transport Of Heavy Metals In Soils Following Reclamation With And Without Biosolid Application, Jarrod O. Miller Jan 2008

Colloid Mediated Transport Of Heavy Metals In Soils Following Reclamation With And Without Biosolid Application, Jarrod O. Miller

University of Kentucky Doctoral Dissertations

Soils disturbed by strip mining practices may have increased colloid loads moving to groundwater resources, also enhancing the transport of contaminants into our water resources. We hypothesize that contaminant transport within soils following mining is enhanced by colloid mobility. Two sites were chosen for this study, a 30-year old reclaimed strip mine in southwest Virginia and a recently mined area from eastern Kentucky. Intact reclaimed soil monoliths were retrieved from sandstone derived soils in southwestern Virginia. Reclaimed monoliths from eastern Kentucky were recreated in the lab. Intact undisturbed (native) soil monoliths representing the soils before mining were also sampled for …


Functional Characterization Of Upd3 In Drosophila Development, Liqun Wang Jan 2008

Functional Characterization Of Upd3 In Drosophila Development, Liqun Wang

University of Kentucky Doctoral Dissertations

The JAK/STAT pathway is a non-receptor tyrosine kinase signaling pathway that is well conserved and highly re-utilized in many mammalian and Drosophila developmental processes. Compared to dozens of ligands and receptors in mammalian JAK/STAT, Drosophila JAK/STAT pathway is simpler with one receptor and three ligands, Upd, Upd2 and Upd3, which have similar amino acid sequences. Previous literature shows that upd and upd2 exhibit the same dynamic striped expression pattern in embryos and have semi-redundant functions during embryogenesis. Do Upd and Upd3 also have redundant functions? To answer this question, the functions of Upd3 in Drosophila development were investigated in this …


Map-Based Cloning Of An Anthracnose Resistance Gene In Medicago Truncatula, Shengming Yang Jan 2008

Map-Based Cloning Of An Anthracnose Resistance Gene In Medicago Truncatula, Shengming Yang

University of Kentucky Doctoral Dissertations

Anthracnose, caused by the fungal pathogen Colletotrichum trifolii, is one of the most destructive diseases of alfalfa worldwide. Cloning and characterization of the host resistance (R) genes against the pathogen will improve our knowledge of molecular mechanisms underlying host resistance and facilitate the development of resistant alfalfa cultivars. However, the intractable genetic system of cultivated alfalfa, owing to its tetrasomic inheritance and outcrossing nature, limits the ability to carry out genetic analysis in alfalfa. Nonetheless, the model legume Medicago truncatula, a close relative of alfalfa, provides a surrogate for cloning the counterparts of many agronomically important genes in …


Comparative Biology Of Seed Dormancy-Break And Germination In Convolvulaceae (Asterids, Solanales), Kariyawasam Marthinna Gamage Gehan Jayasuriya Jan 2008

Comparative Biology Of Seed Dormancy-Break And Germination In Convolvulaceae (Asterids, Solanales), Kariyawasam Marthinna Gamage Gehan Jayasuriya

University of Kentucky Doctoral Dissertations

The biology of seed dormancy and germination of 46 species representing 11 of the 12 tribes in Convolvulaceae were compared in laboratory (mostly), field and greenhouse experiments. Seeds were tested for kind of dormancy and storage behavior; artificial or simulated natural treatments were applied to break physical dormancy (PY); the initial route of water entry (“water gap”) into seeds was identified; the morphoanatomy of the water gap was compared in seeds of 17 species; ontogenetical differences between water gap and seed coat away from the hilum were described in Ipomoea lacunosa seeds; cycling of sensitivity to dormancy break was elucidated …


Roles Of Micrornas In Plant Abiotic Stress, Development And Viral Infection, Venugopal Mendu Jan 2008

Roles Of Micrornas In Plant Abiotic Stress, Development And Viral Infection, Venugopal Mendu

University of Kentucky Doctoral Dissertations

Plant microRNAs play important roles in plant growth and development. Here we investigated the roles of miRNAs in the plant abiotic stress, development and viral infection. MicroRNA membrane array analysis using five different abiotic stress treatments resulted in the identification of 8 novel stress inducible miRNA-families. Functional studies on novel stress inducible miR168 revealed its functional relation with abiotic stress. Over expression of miR168 in Arabidopsis showed upregulation of four stress related miRNAs (miR163, miR167, miR398 and miR408). Analysis of 9 independent transgenic lines showed induction of miR398, an oxidative stress responsive miRNA with a corresponding down regulation of its …


The Influence Of Ca2+ Regulation In Synaptic Facilitation Of Motor Nerve Terminals In Crayfish And Drosophila As Well As In The Physiological Regulation Of Larval Drosophila Heart, Mohati Desai-Shah Jan 2008

The Influence Of Ca2+ Regulation In Synaptic Facilitation Of Motor Nerve Terminals In Crayfish And Drosophila As Well As In The Physiological Regulation Of Larval Drosophila Heart, Mohati Desai-Shah

University of Kentucky Doctoral Dissertations

Intracellular Ca2+ ions are highly regulated in animal cells for them to function normally. Since the tight regulation of [Ca2+]i is so ubiquitous among cells, it is not surprising that altered function in [Ca2+]i regulation is associated with a myriad of disease states in humans. This is particularly evident in pacing myocytes and nerve terminals related to synaptic transmission. A common thread through this dissertation is on the role of three regulators proteins that are common to many cell types. These are the plasmalemmal Na+/Ca2+ exchanger (NCX), the Ca2+-ATPase (PMCA) …


The Role Of Spiders In The Detrital Food Web Of An Eastern Deciduous Forest, Erin Elizabeth Hladilek Jan 2008

The Role Of Spiders In The Detrital Food Web Of An Eastern Deciduous Forest, Erin Elizabeth Hladilek

University of Kentucky Doctoral Dissertations

Historically, terrestrial food web research has focused on describing the structure of aboveground grazing webs, and determining how interactions among plants, herbivores and higher trophic levels influence primary productivity. Detrital food webs however, play a significant role in regulation of ecosystem dynamics through direct impacts on decomposition. Unraveling the complex nature of detrital food web structure is critical to developing a better understanding of ecosystem function. Therefore the primary objective of this research was to describe the structure of the leaf-litter food web in a temperate deciduous forest, with emphasis on interactions between a community of generalist predators, the forest-floor …


Radiocarbon Evidence For The Importance Of Surface Vegetation On Fermentation And Methanogenesis In Contrasting Types Of Boreal Peatlands, J. P. Chanton, P. H. Glaser, L. S. Chasar, David J. Burdige, M. E. Hines, D. I. Seigel, L. B. Tremblay, W. T. Cooper Jan 2008

Radiocarbon Evidence For The Importance Of Surface Vegetation On Fermentation And Methanogenesis In Contrasting Types Of Boreal Peatlands, J. P. Chanton, P. H. Glaser, L. S. Chasar, David J. Burdige, M. E. Hines, D. I. Seigel, L. B. Tremblay, W. T. Cooper

OES Faculty Publications

We found a consistent distribution pattern for radiocarbon in dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), and methane replicated across spatial and temporal scales in northern peatlands from Minnesota to Alaska. The 14C content of DOC is relatively modern throughout the peat column, to depths of 3 m. In sedge-dominated peatlands, the 14C contents of the products of respiration, CH4 and DIC, are essentially the same and are similar to that of DOC. In Sphagnum- and woody plant-dominated peatlands with few sedges, however, the respiration products are similar but intermediate between the 14C contents of …


Co2 Sensitivity Of Southern Ocean Phytoplankton, Philippe D. Tortell, Christopher D. Payne, Yingyu Li, Scarlett Trimborn, Bjorn Rost, Walker O. Smith, Christina Riesselman, Robert B. Dunbar, Peter Sedwick, Giacomo R. Ditullio Jan 2008

Co2 Sensitivity Of Southern Ocean Phytoplankton, Philippe D. Tortell, Christopher D. Payne, Yingyu Li, Scarlett Trimborn, Bjorn Rost, Walker O. Smith, Christina Riesselman, Robert B. Dunbar, Peter Sedwick, Giacomo R. Ditullio

OES Faculty Publications

The Southern Ocean exerts a strong impact on marine biogeochemical cycles and global air-sea CO2 fluxes. Over the coming century, large increases in surface ocean CO2 levels, combined with increased upper water column temps. and stratification, are expected to diminish Southern Ocean CO2 uptake. These effects could be significantly modulated by concomitant CO2-dependent changes in the region's biol. carbon pump. Here we show that CO2 concentrations affect the physiology, growth and species composition. of phytoplankton assemblages in the Ross Sea, Antarctica. Field results from in situ sampling and ship-board incubation experiments demonstrate that inorganic …


Turbulent Lifestyle: Microbial Mats On Earth’S Sandy Beaches—Today And 3 Billion Years Ago, Nora Noffke Jan 2008

Turbulent Lifestyle: Microbial Mats On Earth’S Sandy Beaches—Today And 3 Billion Years Ago, Nora Noffke

OES Faculty Publications

Archean Earth history is very difficult to reconstruct. Until recently, only bacterial cells preserved in chert, microborings, and stromatolites provided the few clues to ancient life. Now, siliciclastic “microbially induced sedimentary structures” (MISS) are adding to our knowledge of both past life and paleoenvironments. MISS rise from the interaction of photoautotrophic microbial mats with physical sediment dynamics in siliciclastic, shallow-marine settings. Archean MISS can be understood through observations of living microbial mats and modern biotic-physical sedimentary processes. Such geobiological studies are key to the interpretation of the early evolution of prokaryotes. For example, the 2.9 Ga Pongola Supergroup, South Africa, …


Ship Ballast Tanks: How Microbes Travel The World, Fred C. Dobbs Jan 2008

Ship Ballast Tanks: How Microbes Travel The World, Fred C. Dobbs

OES Faculty Publications

As the international shipping fleet travels the oceans, it carries with it hidden cargoes of microbes. Fred C. Dobbs explores the hazards posed and what can be done to counteract them.