Contrasting responses of coral reef fauna and foraminiferal assemblages to human influence in La Parguera, Puerto Rico.

Coral reef biota including stony corals, sponges, gorgonians, fish, benthic macroinvertebrates and foraminifera were surveyed in coastal waters near La Parguera, in southwestern Puerto Rico. The goal was to evaluate sensitivity of coral reef biological indicators to human disturbance. Proxies for human disturbance were measured as distance to town (DTT) and rankings of a low-level sediment contamination gradient analyzed from a previous study. Contaminant rank and DTT showed that percent mud, stony coral taxa richness, reef rugosity, and numbers of invertebrates and sponges were higher at sites closer to human disturbance, but a foraminiferal assemblage index was significantly lower at sites with higher proxies for human disturbance. Fish indicators showed no significant relationships with human activity, but associations between fish community measures and certain measures of stony corals, gorgonians and sponges were found. Contrasting responses between foraminifera and reef organisms may be due to greater exposure and sensitivity of foraminifera to sediment contaminants.

Foraminiferal assemblages in Biscayne Bay, Florida, USA: responses to urban and agricultural influence in a subtropical estuary.

This study assessed foraminiferal assemblages in Biscayne Bay, Florida, a heavily utilized estuary, interpreting changes over the past 65 years and providing a baseline for future comparisons. Analyses of foraminiferal data at the genus level revealed three distinct biotopes. The assemblage from the northern bay was characterized by stress-tolerant taxa, especially Ammonia, present in low abundances ( approximately 2.0 x 10(3) foraminifers/gram) though relatively high diversity ( approximately 19 genera/sample). The southwestern margin of the bay was dominated by Ammonia and Quinqueloculina, an assemblage characterized by the lowest diversities ( approximately 12 genera/sample) and highest abundances ( approximately 1.1 x 10(4) foraminifers/gram), influenced by both reduced salinity and elevated organic-carbon concentrations. A diverse assemblage of smaller miliolids and rotaliids ( approximately 26 genera/sample) characterized the open-bay assemblage, which also had a significant component ( approximately 10%) of taxa that host algal endosymbionts. In the past 65 years, populations of symbiont-bearing taxa, which are indicators of normal-marine conditions, have decreased while stress-tolerant taxa, especially Ammonia spp., have increased in predominance.

Conceptual database modeling: a method for enabling end users (radiologists) to understand and develop their information management applications.

As medical technology advances at a rapid pace, clinicians become further and further removed from the design of their own technological tools. This is particularly evident with information management. For radiologists, clinical histories, patient reports, and other pertinent information require sophisticated tools for data handling. However, as databases grow more powerful and sophisticated, systems require the expertise of programmers and information technology personnel. The radiologist, the clinician end-user, must maintain involvement in the development of system tools to insure effective information management. Conceptual database modeling is a design method that serves to bridge the gap between the technological aspects of information management and its clinical applications. Conceptual database modeling involves developing information systems in simple language so that anyone can have input into the overall design. This presentation describes conceptual database modeling, using object role modeling, as a means by which end-users (clinicians) may participate in database development.

Molecular identification of algal endosymbionts in large miliolid foraminifera: 1. Chlorophytes.

Large miliolid foraminifers bear various types of algal endosymbionts including chlorophytes, dinoflagellates, rhodophytes, and diatoms. Symbiosis plays a key role in the adaptation of large foraminifera to survival and growth in oligotrophic seas. The identity and diversity of foraminiferal symbionts, however, remain largely unknown. In the present work we use ribosomal DNA (rDNA) sequences to identify chlorophyte endosymbionts in large miliolid foraminifera of the superfamily Soritacea. Partial 18S and complete Internal Transcribed Spacer (ITS) rDNA sequences were obtained from symbionts of eight species representing all genera of extant chlorophyte-bearing Soritacea. Phylogenetic analysis of the sequences confirms the previous fine structure-based identification of these endosymbionts as belonging to the genus Chlamydomonas. All foraminiferal symbionts form a monophyletic group closely related to Chlamydomonas noctigama. The group is composed of seven types identified in this study, including one previously morphologically described species, Chlamydomonas hedleyi. Each of these types can be considered as a separate species, based on the comparison of genetic differences observed between other established Chlamydomonas species. Several foraminiferal species share the same symbiont type, but only one species, Archaias angulatus, was found to bear more than one type.

Conceptual database modeling for understanding and developing information management applications.

In response to rising health care costs and changing expectations concerning the quality of health care, information management is becoming increasingly important in the practice of medicine; more specifically, it is beginning to effect significant changes in radiology practice and patient care. Radiologic applications of information management include reporting diagnostic information generated from film interpretation as well as tracking utilization patterns of different imaging modalities and the variability of clinical outcomes, documenting the type of information sought by and provided to clinicians, and evaluating departmental quality standards and performance goals. Conceptual database modeling enables radiologists to understand and participate in the development of information systems, thereby improving the likelihood of successful results. In object-role modeling, groups of relevant objects and roles are identified and used to create elementary facts that form the "building blocks" for information models. The resultant models can easily be communicated, reviewed, and revised, allowing decreased development time and optimizing inclusion of relevant features in the target relational database. Increasing the amount of clinical and management input in the development process may help information systems better meet user needs, become accepted and more often used, and ultimately succeed.

Inhibiting sulfate-reducing bacteria in biofilms on steel with antimicrobial peptides generated in situ.

In batch and continuous fermentations, the reduction in corrosion of SAE 1018 mild steel and 304 stainless steel caused by inhibition of the reference sulfate-reducing bacterium (SRB) Desulfovibrio vulgaris by a protective, antimicrobial-producing Bacillus brevis biofilm was investigated. The presence of D. vulgaris produced a thick black precipitate on mild steel and a higher corrosion rate in batch cultures than that seen in a mono-culture of non-antimicrobial-producing Pseudomonas fragi K upon the addition of SRB to the aerobic P. fragi K biofilm. In continuous reactors, the polarization resistance RP decreased for stainless stell and increased for mild steel upon the addition of SRB to a P. fragi K biofilm. Addition of either 200 micrograms/ml ampicillin, chloramphenicol, or ammonium molybdate to batch and continuous reactors after SRB had colonized the metal was ineffective in killing SRB, as inferred from the lack of change in both Rp and the impedance spectra. However, when ampicillin was added prior to SRB colonization, the growth of SRB was completely inhibited on stainless steel in continuous reactors. Prior addition of ampicillin was only able to delay the growth of SRB on mild steel in continuous reactors. External addition of the purified peptide antimicrobial agent gramicidin S prior to the addition of SRB also inhibited the growth of SRB on stainless steel in continuous reactors, and the SRB were also inhibited on stainless steel in both batch and continuous reactors by producing gramicidin S in situ in a protective biofilm when the gramicidin-S-overproducing strain Bacillus brevis 18 was used.