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2007

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Articles 2401 - 2430 of 6758

Full-Text Articles in Physical Sciences and Mathematics

Supramolecular Chemistry Approach To The Design Of A High-Resolution Sensor Array For Multianion Detection In Water, Manuel A. Palacios, Ryuhei Nishiyabu, Manuel Marquez, Pavel Anzenbacher Jr. Jun 2007

Supramolecular Chemistry Approach To The Design Of A High-Resolution Sensor Array For Multianion Detection In Water, Manuel A. Palacios, Ryuhei Nishiyabu, Manuel Marquez, Pavel Anzenbacher Jr.

Chemistry Faculty Publications

Reliable sensing of structurally similar anions in water is a difficult problem, and analytical tests and sensor devices for reliable sensing of multiple anions are very rare. This study describes a method for fabrication of simple colorimetric array-based assays for aqueous anion solutions, including complex analytes encountered in real-life applications. On the fundamental level, this method shows how the discriminatory capacity of sensor arrays utilizing pattern recognition operating in multianalyte environments may be dramatically improved by employing two key features. The synergy between the sensor and hydrogel host resembles the cooperative effects of an apoenzyme and cofactor: the host hydrogel …


Fluctuating Two-State Light Harvesting In A Photosynthetic Membrane, Duohai Pan, Dehong Hu, Ruchuan Liu, Xiaohua Zeng, Samuel Kaplan, H. Peter Lu Jun 2007

Fluctuating Two-State Light Harvesting In A Photosynthetic Membrane, Duohai Pan, Dehong Hu, Ruchuan Liu, Xiaohua Zeng, Samuel Kaplan, H. Peter Lu

Chemistry Faculty Publications

The mechanism by which light is converted into chemical energy in a natural photosynthetic system has drawn considerable research interest. Using fluorescence spectroscopy and microscopic imaging, we have observed fluctuating intermolecular protein fluorescence resonant energy transfers (FRET) among light-harvesting proteins I and II (LH1 and LH2) in bacterial photosynthetic membranes. Using two-channel, FRET, photon-counting detection and a novel, two-dimensional cross-correlation function amplitude-mapping analysis, we revealed fluorescence intensity and spectral fluctuations of donor (LH2) and acceptor (LH1) fluorescence involving FRET. Our results suggest that there are dynamic coupled and noncoupled states of the light-harvesting protein assemblies in photosynthetic membranes. The light-harvesting …


The Stability Of Living Shorelines - An Evaluation, Center For Coastal Resources Management, Virginia Institute Of Marine Science, Marcia Berman, Harry Berquist, Julie Herman, Karinna Nunez Jun 2007

The Stability Of Living Shorelines - An Evaluation, Center For Coastal Resources Management, Virginia Institute Of Marine Science, Marcia Berman, Harry Berquist, Julie Herman, Karinna Nunez

Reports

This project set out to strengthen arguments that living shorelines were a viable and preferred method of erosion control along much of the Chesapeake Bay shoreline. Using statistical tests and data that describe shoreline and environmental condition along tidal shoreline, the study found that indeed marshes are frequently associated with stable shoreline and therefore recommending living shoreline treatments to manage erosion problems was a reasonable strategy that warranted strong consideration. Additional tests revealed a lower occurrence of marshes when traditional erosion control structures like bulkheads and revetments were present. This confirms these structures can permanently impact the growth of tidal …


Closed-Neighborhood Anti-Sperner Graphs, John P. Mcsorley, Alison Marr, Thomas D. Porter, Walter D. Wallis Jun 2007

Closed-Neighborhood Anti-Sperner Graphs, John P. Mcsorley, Alison Marr, Thomas D. Porter, Walter D. Wallis

Articles and Preprints

For a simple graph G let NG[u] denote the closed-neighborhood of vertex uV (G). Then G is closed-neighborhood anti-Sperner (CNAS) if for every u there is a vV (G)\{u} with NG [u] ⊆ NG [v] and a graph H is closed-neighborhood distinct (CND) if every closed-neighborhood is distinct, i.e., if NH[u] ≠ NH[v] when uv, for all u and vV (H).

In this paper we …


Laboratory Based Chemical And Isotopic Investigations On Biotic (Microbial) And Abiotic Reduction Of Iron And Oxidation Of Organic Compounds, Tsigabu Asmelash Gebrehiwet Jun 2007

Laboratory Based Chemical And Isotopic Investigations On Biotic (Microbial) And Abiotic Reduction Of Iron And Oxidation Of Organic Compounds, Tsigabu Asmelash Gebrehiwet

Dissertations

Studies using chemical and isotopic techniques have been conducted to investigate experimental microbial (biotic) iron reduction and abiotic redox processes. In the microbially mediated study Fe(III) reduction and lactate oxidation at circum-neutral pH and anaerobic conditions were used to characterize the metabolic pathways followed by dissimilatory Fe+3 -reducing bacterium Shewanella putrefaciens strain 200R. Iron (II), Iron (III), dissolved inorganic carbon (DIC) and carbon isotope ratios were measured under bicarbonate and phosphate buffered conditions. Carbon isotope disproportionation among organic carbon substrate (lactate), biomass and respired carbon dioxide at the lag to stationary phase of the microbial growth curve showed …


The Multi-Agent Data Collection In Hla-Based Simulation System, Heng-Jie Song, Zhi-Qi Shen, Chunyan Miao, Ah-Hwee Tan, Guo-Peng Zhao Jun 2007

The Multi-Agent Data Collection In Hla-Based Simulation System, Heng-Jie Song, Zhi-Qi Shen, Chunyan Miao, Ah-Hwee Tan, Guo-Peng Zhao

Research Collection School Of Computing and Information Systems

The High Level Architecture (HLA) for distributed simulation was proposed by the Defense Modeling and Simulation Office of the Department of Defense (DOD) in order to support interoperability among simulations as well as reuse of simulation models. One aspect of reusability is to collect and analyze data generated in simulation exercises, including a record of events that occur during the execution, and the states of simulation objects. In order to improve the performance of existing data collection mechanisms in the HLA simulation system, the paper proposes a multi-agent data collection system. The proposed approach adopts the hierarchical data management/organization mechanism …


A Hybrid Of Plot-Based And Character-Based Interactive Storytelling, Yundong Cai, Chunyan Miao, Ah-Hwee Tan, Zhiqi Shen Jun 2007

A Hybrid Of Plot-Based And Character-Based Interactive Storytelling, Yundong Cai, Chunyan Miao, Ah-Hwee Tan, Zhiqi Shen

Research Collection School Of Computing and Information Systems

Interactive storytelling in the virtual environment attracts a lot of research interests in recent years. Story plot and character are two most important elements of a story. Based on these two elements, currently there are two research directions: plot-based and character-based interactive storytelling. However, plot-based approach lacks the refinement of character behaviors as character-based approach. On the other side, character-based approach does not follow a well organized story plot so that the moral of the story might be distorted. Therefore, there is a need to develop an integrated framework to achieve the balance between conveying story moral and enhancing the …


Time Capsule Signature: Efficient And Provably Secure Constructions, Bessie C. Hu, Duncan S. Wong, Qiong Huang, Guomin Yang, Xiaotie Deng Jun 2007

Time Capsule Signature: Efficient And Provably Secure Constructions, Bessie C. Hu, Duncan S. Wong, Qiong Huang, Guomin Yang, Xiaotie Deng

Research Collection School Of Computing and Information Systems

Time Capsule Signature, first formalized by Dodis and Yum in Financial Cryptography 2005, is a digital signature scheme which allows a signature to bear a (future) time t so that the signature will only be valid at time t or later, when a trusted third party called time server releases time-dependent information for checking the validity of a time capsule signature. Also, the actual signer of a time capsule signature has the privilege to make the signature valid before time t.In this paper, we provide a new security model of time capsule signature such that time server is not required …


A More Natural Way To Construct Identity-Based Identification Schemes, Guomin Yang, Jing Chen, Duncan S. Wong, Xiaotie Deng, Dongsheng Wang Jun 2007

A More Natural Way To Construct Identity-Based Identification Schemes, Guomin Yang, Jing Chen, Duncan S. Wong, Xiaotie Deng, Dongsheng Wang

Research Collection School Of Computing and Information Systems

Constructing identification schemes is one of the fundamental problems in cryptography, and is very useful in practice. An identity-based identification (IBI) scheme allows a prover to identify itself to a public verifier who knows only the claimed identity of the prover and some common information. In this paper, we propose a simple and efficient framework for constructing IBI schemes. Unlike some related framework which constructs IBI schemes from some standard identification schemes, our framework is based on some more fundamental assumptions on intractable problems. Depending on the features of the underlying intractable problems presumed in our framework, we can derive …


Are Radio Sources And Gamma Ray Bursts Luminal Booms?, Manoj Thulasidas Jun 2007

Are Radio Sources And Gamma Ray Bursts Luminal Booms?, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

The softening of a Gamma Ray Burst (GRB) afterglow bears remarkable similarities to the frequency evolution in a sonic boom. Atthe front end of the sonic boom cone, the frequency is infinite, much like a GRB. Inside the cone, the frequencyrapidly decreases to infrasonic ranges and the sound source appears at two places at the same time,mimicking the double-lobed radio sources. Although a “luminal” boom violates the Lorentz invarianceand is therefore forbidden, it is tempting to work out the details and compare them with existing data. This temptation is further enhanced by the observed superluminality in the celestial objects associated …


Vertically Coupled Microring Laser Devices Based On Inp Using Bcb Wafer Bonding, M. Hamacher, H. Heidrich, U. Troppenz, D. Syvridis, D. Alexandropoulos, S. Mikroulis, A. Kapsalis, Chyng Wen Tee, K. A. Williams, V. Dragoi, M. Alexe, D. Cristea, M. Kusko Jun 2007

Vertically Coupled Microring Laser Devices Based On Inp Using Bcb Wafer Bonding, M. Hamacher, H. Heidrich, U. Troppenz, D. Syvridis, D. Alexandropoulos, S. Mikroulis, A. Kapsalis, Chyng Wen Tee, K. A. Williams, V. Dragoi, M. Alexe, D. Cristea, M. Kusko

Research Collection Lee Kong Chian School Of Business

In this paper, we present our approach on the realization of vertical coupling technology that has been verified for microlaser fabrication as well as for the realization of high Q resonators with 'loss-less' cavities based on InP. The concept is based on full wafer technology and provides the integration of an optical transparent passive bus waveguide vertically coupled to the active ring laser.


Simplifying Cyber Foraging For Mobile Devices, Rajesh Krishna Balan, Darren Gergle, Mahadev Satyanarayanan, James Herbsleb Jun 2007

Simplifying Cyber Foraging For Mobile Devices, Rajesh Krishna Balan, Darren Gergle, Mahadev Satyanarayanan, James Herbsleb

Research Collection School Of Computing and Information Systems

Cyber foraging is the transient and opportunistic use of compute servers by mobile devices. The short market life of such devices makes rapid modification of applications for remote execution an important problem. We describe a solution that combines a "little language" for cyber foraging with an adaptive runtime system. We report results from a user study showing that even novice developers are able to successfully modify large, unfamiliar applications in just a few hours. We also show that the quality of novice-modified and expert-modified applications are comparable in most cases.


Dispersion Measure Variations And Their Effect On Precision Pulsar Timing, X. P. You, G. Hobbs, W. A. Coles, R. N. Manchester, R. Edwards, M. Bailes, J. Sarkissian, J. P.W. Verbiest, W. Van Straten, A. Hotan, S. Ord, F. Jenet, N. D.R. Bhat, A. Teoh Jun 2007

Dispersion Measure Variations And Their Effect On Precision Pulsar Timing, X. P. You, G. Hobbs, W. A. Coles, R. N. Manchester, R. Edwards, M. Bailes, J. Sarkissian, J. P.W. Verbiest, W. Van Straten, A. Hotan, S. Ord, F. Jenet, N. D.R. Bhat, A. Teoh

Physics and Astronomy Faculty Publications and Presentations

We present an analysis of the variations seen in the dispersion measures (DMs) of 20-ms pulsars observed as part of the Parkes Pulsar Timing Array project. We carry out a statistically rigorous structure function analysis for each pulsar and show that the variations seen for most pulsars are consistent with those expected for an interstellar medium characterized by a Kolmogorov turbulence spectrum. The structure functions for PSRs J1045-4509 and J1909-3744 provide the first clear evidence for a large inner scale, possibly due to ion-neutral damping. We also show the effect of the solar wind on the DMs and show that …


Services Computing, Liang-Jie Zhang, Jia Zhang, Hong Cai May 2007

Services Computing, Liang-Jie Zhang, Jia Zhang, Hong Cai

Jia Zhang

This book bridges the gap between Business and IT services. It describes research results in Web services and service-oriented architecture (SOA); business consulting methodology and utilities; and business process modeling, transformation, integration, and management. Major solution architectures, technologies and research methods are discussed in the lifecycle of services innovation research, including business componentization; services modeling, creation, realization, annotation, deployment, discovery, composition and delivery; service-to-service collaboration; and services monitoring, optimization, and management. The book provides readers with new research and solution methods to enable IT services and computing technology to better create and manage business services, which is the goal of …


Design Of A Gas Tight Water Sampler For Auv Operations, Christopher Roman, R. Camilli May 2007

Design Of A Gas Tight Water Sampler For Auv Operations, Christopher Roman, R. Camilli

Christopher N. Roman

This paper presents the design and preliminary test results for a small gas tight water sampler intended to work on scientific AUVs. In recent years AUVs have developed into reliable platforms capable of carrying a wide variety of environmental sensors for in-situ chemical measurements. Physical sample collection however remains difficult, due to the combination of space, power and complexity constraints inherent in working with autonomous platforms. The AUV sampler is a small (12 cm times 85 cm) cylindrical package designed to collect eight 20 ml gas tight volumes of water, with each sample maintained at high pressure to depths of …


On The Gauge Equivalence Of Twisted Quantum Doubles Of Elementary Abelian And Extra-Special 2-Groups, Christopher Goff, Geoffrey Mason, Siu-Hung Ng May 2007

On The Gauge Equivalence Of Twisted Quantum Doubles Of Elementary Abelian And Extra-Special 2-Groups, Christopher Goff, Geoffrey Mason, Siu-Hung Ng

Christopher Goff

We establish braided tensor equivalences among module categories over the twisted quantum double of a finite group defined by an extension of a group H by an abelian group, with 3-cocycle inflated from a 3-cocycle on H. We also prove that the canonical ribbon structure of the module category of any twisted quantum double of a finite group is preserved by braided tensor equivalences. We give two main applications: first, if G is an extra-special 2-group of width at least 2, we show that the quantum double of G twisted by a 3-cocycle w is gauge equivalent to a twisted …


A Large-Scale Rheumatoid Arthritis Genetic Study Identifies Association At Chr 9q33.2, Steven J. Schrodi May 2007

A Large-Scale Rheumatoid Arthritis Genetic Study Identifies Association At Chr 9q33.2, Steven J. Schrodi

Steven J Schrodi

No abstract provided.


Baryons And Mesons With Beauty, Goldstein R. Gary, Kameshwar C. Wali May 2007

Baryons And Mesons With Beauty, Goldstein R. Gary, Kameshwar C. Wali

Physics - All Scholarship

Recent experimental findings of several mesons and baryons with "beauty" and "charm" as flavors remind us of the days when strangeness was discovered, and how its inclusion led to SU(3)-flavor symmetry with enormous success in the classification of the "proliferated" states into SU(3) multiplets. One of the key elements was the successful application of the first order perturbation in symmetry breaking, albeit what then appeared to be huge mass differences, and the prediction of new states that were confirmed by experiments. In this note, we venture into the past and, applying the same techniques, predict some new "beauty-" and "charm-" …


Problems Related To Efficacy Measurement And Analyses, Sibabrata Banerjee May 2007

Problems Related To Efficacy Measurement And Analyses, Sibabrata Banerjee

Dissertations

In clinical research it is very common to compare two treatments on the basis of an efficacy variable. More specifically, if X and Y denote the responses of patients on the two treatments A and B, respectively, the quantity P(Y>X) (which can be called the probabilistic index for the Effect Size), is of interest in clinical statistics. The objective of this study is to derive an efficacy measure that would compare two treatments more informatively and objectively compared to the earlier approaches. Kernel density estimation is a useful non-parametric method that has not been well utilized as an applied …


Prediction Of Mrna Polyadenylation Sites In The Human Genome And Mathematical Modeling Of Alternative Polyadenylation, Yiming Cheng May 2007

Prediction Of Mrna Polyadenylation Sites In The Human Genome And Mathematical Modeling Of Alternative Polyadenylation, Yiming Cheng

Dissertations

Messenger RNA (mRNA) polyadenylation plays many important roles in the cell, such as transcription termination, mRNA stability and transportation, and mRNA translation in eukaryotic cells. A large number of human and mouse genes have multiple polyadenylation sites (referred to as poly(A) sites) that lead to variable transcripts, some of which are translated into various protein products with different functions. However, the details about when and where the polyadenylation occurs, and how pre-mRNA switches from one poly(A) site to another are still unknown. This kind of 3 '-end processing can be regulated by the cell environment, cell cycle stage, and tissue …


People-Search : Searching For People Sharing Similar Interests From The Web, Quanzhi Li May 2007

People-Search : Searching For People Sharing Similar Interests From The Web, Quanzhi Li

Dissertations

On the Web, there are limited ways of finding people sharing similar interests or background with a given person. The current methods, such as using regular search engines, are either ineffective or time consuming. In this work, a new approach for searching people sharing similar interests from the Web, called People-Search, is presented. Given a person, to find similar people from the Web, there are two major research issues: person representation and matching persons. In this study, a person representation method which uses a person's website to represent this person's interest and background is proposed. The design of matching process …


Sifting Customers From The Clickstream : Behavior Pattern Discovery In A Virtual Shopping Environment, Peishih Chang May 2007

Sifting Customers From The Clickstream : Behavior Pattern Discovery In A Virtual Shopping Environment, Peishih Chang

Dissertations

While shopping online, customers' needs and goals may change dynamically, based on a variety of factors such as product information and characteristics, time pressure and perceived risk. While these changes create emergent information needs, decisions about what information to present to customers are typically made before customers have visited a web site, using data such as purchase histories and logs of web pages visited. Better understanding of customer cognition and behavior as a function of various factors is needed in order to enable the right information to be presented at the right time. One approach to achieving this understanding is …


Ligand-Based Drug Design : I. Conformational Studies Of Gbr 12909 Analogs As Cocaine Antagonists; Ii. 3d-Qsar Studies Of Salvinorin A Analogs As Kappa Opioid Agonists, Deepangi Pandit May 2007

Ligand-Based Drug Design : I. Conformational Studies Of Gbr 12909 Analogs As Cocaine Antagonists; Ii. 3d-Qsar Studies Of Salvinorin A Analogs As Kappa Opioid Agonists, Deepangi Pandit

Dissertations

Ligand-based drug design (LBDD) techniques are applied when the structure of the receptor is unknown but when a series of compounds or ligands have been identified that show the biological activity of the interest. Generally, availability of a series of compounds with high activity, with no activity, and also with a range of intermediate activities for the desired biological target is required. It is common that structures of membrane-bound proteins (for example, monoamine transporter proteins and opioid receptor proteins) are unknown as these proteins are notoriously difficult to crystallize.

In Part I of this study, analogs of the flexible dopamine …


Long Exposure Point Spread Function Estimation From Solar Adaptive Optics Loop Data, Jose Marino May 2007

Long Exposure Point Spread Function Estimation From Solar Adaptive Optics Loop Data, Jose Marino

Dissertations

Adaptive optics (AG) systems provide partial correction to wavefront distortions introduced by the Earth's atmosphere. They have become an essential tool to obtain diffraction-limited observations from ground-based telescopes. However, the AG correction is only partial and post-processing with a good estimate of the point spread function (PSF) is required.

PSF estimates are impossible to measure directly during solar observations due to the lack of point sources in the field-of-view. Moreover, the highly variable day-time seeing conditions require the estimated PSF to be simultaneous with the captured image. A method is presented to estimate the long-exposure PSF of AG-corrected solar observations …


Construction Of Fasr Subsystem Testbed And Application For Solar Burst Trajectories And Rfi Study, Zhiwei Liu May 2007

Construction Of Fasr Subsystem Testbed And Application For Solar Burst Trajectories And Rfi Study, Zhiwei Liu

Dissertations

The construction of the Frequency Agile Solar Radiotelescope (FASR) Subsystem Testbed (FST) and observational results are described. Three antennas of Owens Valley Solar Array (OVSA) have been upgraded with newly designed, state of art technology. The 1-9 GHz RF signal from the antenna feed is transmitted via broadband (45 MHz-9.5 GHz) optical fiber links to the control room. The RF is then downconverted to a 500 MHz, single-sideband signal that can be tuned across the 1-9 GHz RF band. The data are sampled with an 8-bit, 1 GHz sampling-rate digitizer, and further saved to a computer hard disk. The full-resolution …


A Comprehensive Wetland Program For Fringing Salt Marshes In The York River, Maine, Pamela A. Morgan, Jeremy Miller, Christopher Cayce Dalton, Michele Dionne May 2007

A Comprehensive Wetland Program For Fringing Salt Marshes In The York River, Maine, Pamela A. Morgan, Jeremy Miller, Christopher Cayce Dalton, Michele Dionne

Environmental Studies Faculty Publications

The overall goal of this project was to assist the Town of York, Maine, in its efforts to monitor and protect the fringing salt marshes along the York River. In particular, the project focused on potential impacts to the marshes due to shoreline development pressures. Specific objectives included (1) gathering baseline data about the marshes (2) developing a set of indicators to be used in future monitoring, and (3) generating management recommendations.


Cooperative Conservation: Increasing Capacity Through Community Partnerships Interagency Volunteer Program: Final Project Report, May 31 2007, Margaret N. Rees May 2007

Cooperative Conservation: Increasing Capacity Through Community Partnerships Interagency Volunteer Program: Final Project Report, May 31 2007, Margaret N. Rees

Get Outdoors Nevada

  • Was recognized with two consecutive National Take Pride in America Awards (2005 and 2006) in the Federal Program category.
  • Created a central clearinghouse created for Southern Nevada public lands volunteers, including:─ an online volunteer data‐management application (Volgistics) adopted and customized for the program and populated with 2,866 active and 974 prospective volunteer records ─ a community outreach Web site that currently averages 57,930 hits per month and has aided in the recruitment of 1,211 volunteers ─ branding development and marketing and outreach tool creation
  • Developed Standard Operating Procedures (SOPs) for all areas of Interagency Volunteer Program Management—recruitment, training, recognition, retention …


Domains Of Definition Of Monge-Ampère Operators On Compact Kähler Manifolds, Dan Coman, Vincent Guedj, Ahmed Zeriahi May 2007

Domains Of Definition Of Monge-Ampère Operators On Compact Kähler Manifolds, Dan Coman, Vincent Guedj, Ahmed Zeriahi

Mathematics - All Scholarship

Let (X, w) be a compact Kahler manifold. We introduce and study the largest set DMA(X, w) of w-plurisubharmonic (psh) functions on which the complex Monge-Ampere operator is well defined. It is much larger than the corresponding local domain of definition, though still a proper subset of the set PSH(X, w) of all w-psh functions. We prove that certain twisted Monge-Ampere operators are well defined for all w-psh functions. As a consequence, any w-psh function with slightly attenuated singularities has finite weighted Monge-Ampere energy.


Exploring The Integration Of Memory Management And Trusted Computing, Nihal A. D'Cunha May 2007

Exploring The Integration Of Memory Management And Trusted Computing, Nihal A. D'Cunha

Dartmouth College Master’s Theses

This thesis addresses vulnerabilities in current Trusted Computing architecture by exploring a design for a better Trusted Platform Module (TPM); one that integrates more closely with the CPU's Memory Management Unit (MMU). We establish that software-based attacks on trusted memory can be carried out undetectably by an adversary on current TCG/TPM implementations. We demonstrate that an attacker with sufficient privileges can compromise the integrity of a TPM-protected system by modifying critical loaded code and static data after measurement has taken place. More specifically, these attacks illustrate the Time Of Check vs. Time of Use (TOCTOU) class of attacks. We propose …


New Species And Host Associations Of Commensal Leucothoid Amphipods From Coral Reefs In Florida And Belize (Crustacea:Amphipoda), James Darwin Thomas, Kristine N. Klebba May 2007

New Species And Host Associations Of Commensal Leucothoid Amphipods From Coral Reefs In Florida And Belize (Crustacea:Amphipoda), James Darwin Thomas, Kristine N. Klebba

Marine & Environmental Sciences Faculty Articles

Six new amphipod species in the genus Leucothoe from the tropical western Atlantic Ocean are described and illustrated. Extensive field collecting and specialized underwater collecting techniques have documented 43 new invertebrate host records for these new taxa. Four of these new species inhabit interior canals of sponges; Leucothoe barana n.sp., Leucothoe garifunae n.sp., Leucothoe saron n.sp., and Leucothoe ubouhu n.sp. A remarkable new species, Leucothoe flammosa n.sp., nestles in the gills of seven species of bivalve mollusks. A single species, Leucothoe wuriti n.sp., appears restricted to the branchial chamber of two species of solitary ascidians. Detailed illustrations and scanning electron …