From egg to hatchling: preferential retention of fatty acid biomarkers in young-of-the-year Port Jackson sharks Heterodontus portusjacksoni.

The muscle and liver fatty acid composition of young-of-the-year (YOY) Port Jackson sharks Heterodontus portusjacksoni were investigated to determine the effects of a known dietary lipid source v. maternal input as demonstrated by egg yolk fatty acid profiles. Ten Heterodontus portusjacksoni egg yolks were collected in situ and compared with four hatched H. portusjacksoni fed a known diet in a controlled feeding experiment of 185 days. This study demonstrated that fatty acids are probably conservatively transferred from egg yolks to YOY H. portusjacksoni, while diet did not have a large effect on the fatty acid composition of the liver or muscle.

Telemedicine for the delivery of professional development for health, education and welfare professionals in two remote mining towns.

Over a two-year period, telemedicine was used to deliver training and development services for health, education and welfare staff in two remote towns in South Australia - Roxby Downs and Coober Pedy. Both are mining towns but they have different profiles in terms of the community's mental health needs. The services were provided by the Child and Adolescent Mental Health Services (CAMHS) from the Women's and Children's Hospital in Adelaide, South Australia. The media used were videoconferencing, telephone, video-tapes, the Internet and printed material. During 1998-9, professional staff in the two locations participated in structured videoconferencing seminars that addressed important mental health topics, chosen in response to surveys of the needs of the participants. The videoconferencing sessions were sometimes used to discuss specific patient cases. Each remote town was also supported via videoconferencing by a nominated office of the CAMHS: Roxby Downs by the suburban office at Port Adelaide and Coober Pedy by the office in the industrial town of Port Pirie. This customized support was an important factor in the success of the professional development network.

Bacterial swimming strategies and turbulence.

Most bacteria in the ocean can be motile. Chemotaxis allows bacteria to detect nutrient gradients, and hence motility is believed to serve as a method of approaching sources of food. This picture is well established in a stagnant environment. In the ocean a shear microenvironment is associated with turbulence. This shear flow prevents clustering of bacteria around local nutrient sources if they swim in the commonly assumed "run-and-tumble" strategy. Recent observations, however, indicate a "back-and-forth" swimming behavior for marine bacteria. In a theoretical study we compare the two bacterial swimming strategies in a realistic ocean environment. The "back-and-forth" strategy is found to enable the bacteria to stay close to a nutrient source even under high shear. Furthermore, rotational diffusion driven by thermal noise can significantly enhance the efficiency of this strategy. The superiority of the "back-and-forth" strategy suggests that bacterial motility has a control function rather than an approach function under turbulent conditions.

The enhancement of audience participation in telemedicine education by the use of electronic voting.

The rotation of trainee registrars in obstetrics and gynaecology to peripheral centres in South Australia was introduced for the first time in January 1998. A pilot study of the use of telemedicine to maintain the trainees' involvement in the established weekly training sessions conducted at the Women's and Children's Hospital (WCH) was also commenced at the same time. Sessions were problem based and required the trainees to be actively involved throughout. An electronic voting system (EVS) was used by the WCH audience, with the results of all responses being seen at the peripheral centres. Initial evaluation of the EVS as an educational tool was sufficiently positive to justify further studies of its use in this environment. The availability of voting units at the peripheral sites, used in conjunction with the main centre, will provide an exciting opportunity for further research.

The uneven diffusion of telemedicine services in Australia.

The diffusion of telemedicine services in Australia over the last four years has been uneven. Some of the major barriers to the adoption of telemedicine relate to the nature of the industry, including its immaturity, the limited telecommunications infrastructure, the lack of appropriate dialogue between vendors and buyers about solutions required, and the lack of partnerships in the industry. Remuneration is only one barrier. There are, of course, other substantial organizational, financial and attitudinal barriers to the adoption of telemedicine. Further development of telemedicine in Australia will require detailed assessment of these matters.

Clinical applications of renal telemedicine.

In 1994, a telemedicine network was established linking the renal unit at The Queen Elizabeth Hospital to three satellite dialysis centres in South Australia. In the first two and a half years of operation, the telemedicine equipment was used on over 6000 occasions. Interviews were conducted with 18 medical, nursing and allied health staff and dialysis patients. The main finding was that the full range of staff, from surgeons and nephrologists to allied health staff and nurses, were able use the technology successfully for clinical purposes. A second finding was that the technology enabled staff to perform a wide range of clinical procedures, from routine outpatient consultations and monitoring infections to making decisions about retrieval or confirming decisions to operate. A third finding was that telemedicine enabled the renal unit to provide improved services in which teams of staff at the different sites cooperated in ways that were not possible before the telemedicine links became available.

Formation of 30- to 40-micrometer-thick laminations by high-speed marine bacteria in microbial mats.

The precision with which motile heterotrophic bacteria could position themselves in microbial mats was determined. This required the development of a technique to view motile bacteria in situ. This was successfully achieved by replacing a 1-cm-diameter minicore from the mat sediment with 210- to 300-(mu)m-diameter glass beads or sieved agar. After allowing 3 days for regrowth of the mat into the transparent medium, a cross section showed that bacteria formed a layer as thin as 30 to 40 (mu)m at a depth of 500 (mu)m below the surface. Bacterial concentrations in this microlamination were 20 times above background. Mean speeds were 200 (mu)m s(sup-1) inside and 60 (mu)m s(sup-1) outside the microlamination. The percentages of bacteria turning per 30 s were 93% inside and 10% outside the microlamination. Artificial chemical gradients were unsuccessful in stimulating microlamination formation or in eliciting the same extent of speed and turning responses. The significance of the results is that it is now possible to microscopically examine sedimentary bacteria in situ. Our first examination indicates that some bacteria form chemotactic microlaminations by increasing their turning frequency. This behavior is opposite that described in the enteric-based model of chemotactic movement, in which positive chemotaxis is achieved by decreasing the turning frequency.

Clustering of marine bacteria in seawater enrichments.

Seawater enrichments of marine bacteria clustered in 20- to 50-(mu)m-wide bands near air-water interfaces. The cells within the band travelled at up to 212 (mu)m s(sup-1) and at an average speed of 163 (mu)m s(sup-1). Mean cell speeds peaked mid-run at 187 (mu)m s(sup-1). At the end of the run, bacteria reversed direction rather than randomly reorienting. The duration of the stops during reversal was estimated at 18 ms, six to seven times shorter than that found in enteric bacteria. Cells hundreds of micrometers from the band travelled at half the speed of the bacteria in the band. The fastest isolate from the seawater enrichment was identified as Shewanella putrefaciens and had an average speed of 100 (mu)m s(sup-1) in culture. Air-water interfaces produced no clustering or speed changes in isolates derived from enrichments. Salinity and pH, however, both influenced speed. The speed and reversal times of the seawater enrichments indicate that the bacteria in them are better adapted for clustering around small point sources of nutrients than are either enteric or cultured marine bacteria.

User adoption issues in renal telemedicine.

We carried out a longitudinal survey to evaluate the users' attitudes to the introduction of telemedicine into the dialysis units of a renal ward in South Australia. The first questionnaire was distributed to all members of staff involved with the introduction of the system. There were 44 responses (80%). Staff were fairly positive about the telemedicine system, and felt that it was easy to use and reliable. They also clearly felt that the confidentiality and privacy offered by the system in an open ward were unsatisfactory. A second questionnaire was distributed to all staff about six months later and there were 40 responses (66%). Of these, 22 could be matched with the responses from the first survey (a response rate of 50% from the first sample). There were no significant differences in the staff members' feelings between the two surveys, except in two cases: there were significant changes in staff opinion about the degree of confidentiality (P < 0.05) and privacy (P < 0.01) offered by the system, with attitudes becoming more positive in each case. The results indicate the need for dialogue with users, in order to address their concerns regarding the system and practical difficulties. This study highlights the importance of planning, effort, cooperation and an appropriate culture within a renal unit in order for telemedicine to be accepted.

Natural assemblages of marine bacteria exhibiting high-speed motility and large accelerations.

Natural communities of marine bacteria, an isolate (FMB-Bf3) from one marine community, and Escherichia coli were examined by video microscopy for the magnitude and uniformity of their speed. Natural communities formed tight microswarms that showed higher speeds (mean = 230 microns s-1) than did E. coli (15 microns s-1) or FMB-Bf3 (mean = 62 microns s-1). Outside the microswarms, the marine bacteria slowed to 45 microns s-1. Between turns, in mid run, and while travelling in straight lines, the natural-community bacteria accelerated up to 1,450 microns s-2 while the cultured bacteria showed maximum accelerations of 70 and 166 microns s-2. The frequency distribution of speed change for the marine bacteria was skewed towards a few large negative accelerations and a range of positive accelerations. The general pattern was one of relatively slow increases in speed followed by abrupt declines. The results indicate that the mechanical generation and energetic maintenance, as well as the environmental function, of bacterial motility need reappraisal. We conclude that the standard bacterial motility parameters of low and uniform speed, derived from culture-based studies, are not necessarily applicable to marine bacterial communities.

Long lag times and high velocities in the motility of natural assemblages of marine bacteria.

The motility characteristics of natural assemblages of coastal marine bacteria were examined. Initially, less than 10% of the bacteria were motile. A single addition of tryptic soy broth caused an increase in the motile fraction of cells but only after 7 to 12 h. Motility peaked at 15 to 30 h, when more than 80% of cells were motile. These results support the proposal that energy limits motility in the marine environment. Cell speeds changed more than an order of magnitude on timescales of milliseconds and hours. The maximum community speed was 144 (mu)m s(sup-1), and the maximum individual burst velocity was 407 (mu)m s(sup-1). In uniform medium, speed was an inverse function of tryptic soy broth concentration, declining linearly over 0.001 to 1.0%. In media where concentration gradients existed, the mean speed was a function of position in a spatial gradient, changing from 69 to 144 (mu)m s(sup-1) over as little as 15 to 30 (mu)m. The results suggest that marine bacteria are capable of previously undescribed quick shifts in speed that may permit the bacteria to rapidly detect and keep up with positional changes in small nutrient sources. These high speeds and quick shifts may reflect the requirements for useful motility in a turbulent ocean.

A practical optical trap for manipulating and isolating bacteria from complex microbial communities.

A wide variety of naturally occurring bacteria cannot be isolated by classical microbiological methods, hindering study of microbial communities. To partially remove this limitation, a method using optical trapping was developed. It allows for one-step isolation of bacteria from a complex community to a pure culture. The method transfers a single bacterium to sterile culture medium using a non-destructive laser beam. The ease with which a previously unculturable cell was cultured by trapping suggests that competition may limit growth in some natural communities of bacteria.

Florida Department of Corrections' substance abuse programs.

The Florida Department of Corrections has worked diligently to plan and implement a system of comprehensive institutional and community-based programs. These programs strive to establish a functional, cost-effective continuum of care for incarcerated individuals while providing necessary linkages essential to transferring inmates back into society with the knowledge and social skills necessary to lead a drug-free life. It is believed that a viable working model has been developed that will offer inmate services and, ultimately, afford them the opportunity and appropriate linkages to continue treatment as needed after incarceration.

Progressive platelet activation with storage: evidence for shortened survival of activated platelets after transfusion.

Platelets are known to become activated during storage, but it is unclear whether such activation affects recovery or survival after platelet concentrate (PC) transfusion. With the use of flow cytometry to determine the percentage of platelets expressing the alpha-granule membrane protein 140 (GMP-140), a known adhesive ligand appearing on the platelet surface after activation, several studies were conducted. These investigations evaluated 1) the occurrence of significant platelet activation over time in PCs (n = 46) stored under standard blood bank conditions; 2) the correlation between platelet activation and platelet recovery in normal subjects after PC storage (n = 12), as assessed by the recovery of Indium-labeled platelets; and 3) the recovery of activated and unactivated platelets in thrombocytopenic cancer patients transfused with standard PCs (n = 11). It was determined 1) that an increasing duration of storage of PC was associated with increasing platelet activation as measured by the percentage of platelets expressing GMP-140, progressing from a mean of 4 +/- 2 percent (SD) on the day of collection to a mean of 25 +/- 8 percent by 5 days of storage: 2) that, in normal subjects, posttransfusion recovery of autologous platelets stored for 2 to 4 days and then labeled with In111 was inversely correlated with the percentage of activated platelets in the transfused PC (r = -0.55, p = 0.05); and 3) that, when thrombocytopenic patients were transfused with standard PCs, the recovery of the activated platelets in the transfused PCs averaged only 38 +/- 15 percent of the number predicted by the absolute platelet increment.(ABSTRACT TRUNCATED AT 250 WORDS)

Velocity changes, long runs, and reversals in the Chromatium minus swimming response.

The velocity, run time, path curvature, and reorientation angle of Chromatium minus were measured as a function of light intensity, temperature, viscosity, osmotic pressure, and hydrogen sulfide concentration. C. minus changed both velocity and run time. Velocity decreased with increasing light intensity in sulfide-depleted cultures and increased in sulfide-replete cultures. The addition of sulfide to cultures grown at low light intensity (10 microeinsteins m-2 s-1) caused mean run times to increase from 10.5 to 20.6 s. The addition of sulfide to cultures grown at high light intensity (100 microeinsteins m-2 s-1) caused mean run times to decrease from 15.3 to 7.7 s. These changes were maintained for up to an hour and indicate that at least some members of the family Chromatiaceae simultaneously modulate velocity and turning frequency for extended periods as part of normal taxis.

The influence of cell size on marine bacterial motility and energetics.

The influence of Brownian motion on marine bacteria was examined. Due to their small size, marine bacteria rotate up to 1,400 degrees in one second. This rapid rotation makes directional swimming difficult or impossible, as a bacterium may point in a particular direction for only a few tens of milliseconds on average. Some directional movement, however, was found to be possible if swimming speed is sufficiently great, over approximately 100 µm sec(-1). This led to the testable hypothesis that marine bacteria with radiii less than about 0.75 µm should exceed this speed. The result of the increased speed is that marine bacteria may spend in excess of 10% of their total energy budget on movement. This expenditure is 100 times greater than values for enteric bacteria, and indicates that marine bacteria are likely to be immotile below critical size-specific nutrient concentrations.