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We investigated effects of elevated partial pressure of CO2 (pCO2) on the metabolism of epilithic and endolithic phototrophic communities that colonized experimental coral blocks. Blocks of the massive coral Porites lobata were exposed to colonization by epilithic and endolithic organisms at an oceanic site in Kaneohe Bay (Hawaii) for 6 months, and then were transported to laboratory tanks. A bubbling system was used to maintain two treatments for 3 months, one at ambient pCO2 (400 ppm) and the second at elevated pCO2 (750 ppm). Net photosynthetic rates of epilithic communities in the high pCO2 treatment, dominated by encrusting coralline algae, decreased by 35% while respiration rates remained constant. In contrast, metabolism of endolithic phototrophs, comprised of cyanobacteria and algae, was not significantly affected by the elevated pCO2 even though endoliths contributed about 63% to block production.

We have developed a simple technique to decorrelate remote sensing color band data from depth in optically shallow water. The method linearizes color band data with respect to depth by subtracting an optically deepwater value from the entire waveband under consideration and taking the natural logarithm of the result. Next, this linearized waveband is rotated about the model 2 regression line computed against a bathymetry band. The rotated color band is decorrelated from water depth. We demonstrate the technique for a small area of Kailua Bay, Oahu, HI, using Quickbird multispectral and Scanning Hydrographic Operational Airborne Lidar Survey LIDAR data. Results indicate that color band data are effectively decorrelated from depth, while bottom reflector variability is maintained, thus providing the basis for further analysis of the depth-invariant wavebands. The primary benefit of our technique is that wavebands are rotated independently, preserving relative spectral information.

To quantify the contribution of endolithic phototrophs to primary production of dead carbonate substrates, experimental blocks of cleaned Porites lobata Dana skeleton were placed at three different sites in Kaneohe Bay, Hawaii: inshore, lagoonal, and oceanic. After 6 months of exposure, experimental blocks were colonized by communities characteristic of their estuarine (inshore, lagoonal) and oceanic (ocean) environments. Blocks were subsampled; net photosynthesis (NP) and chl a concentrations of the whole blocks (epi- and endoliths) and scrapped blocks (only endoliths) were quantified. Green turf algae colonized predominantly inshore and lagoonal blocks, while encrusting corallines were the dominant epiliths colonizing oceanic blocks. Four main species of endolithic phototrophs were identified in all blocks: Mastigocoleus testarum Lagerheim, Plectonema terebrans Bornet and Flahault (cyanobacteria), Phaeophila dendroides Crouan and Crouan, and Ostreobium quekettii Bornet and Flahault (Chlorophytes). While epiliths were very different between sites, NP rates and chl a concentration of endoliths did not vary significantly and were positively correlated (191 ± 25 mmol C·m -2 ·day -1 and 590 ± 150 mg chl a · m 2 of reef, respectively). Assimilation numbers for whole communities, including both epilithic and endolithic communities, were similar to those measured for endolithic communities alone (average of 0.3 g C-g chl a·h -1 ). Under experimental conditions, the contribution of endolithic phototrophs to community NP rates of blocks ranged from 56% to 81%, and under natural conditions, we estimated that this contribution ranged between 32% and 46%. Thus, we showed that the endolithic phototrophs are one of the major primary producers in dead coral substrates in a wide range of coral reef environments.

Steroidal estrogens are well-described vertebrate hormones that also occur in inverte- brates, where they have diverse biological effects. Estradiol-17β is contained in coral tissues and released into the surrounding water during multi-species coral mass-spawning events. Estrogens are also widely distributed environmental pollutants in coastal waters; thus corals and other reef inverte- brates are exposed to a variety of estrogens and estrogen-like compounds with unknown organismal and ecological effects. Until now, there has been no experimental evidence to suggest that estrogens are biologically active in corals. We describe the effects of exogenous estradiol on the size and num- ber of gametes spawned by coral colonies and the effects of estrone on coral growth rates and tissue thickness. Montipora capitata coral colonies treated with estradiol for 3 wk prior to spawning released fewer egg-sperm bundles than controls (29% decrease). Porites compressa coral fragments ('nubbins') exposed continuously to estrone for 2 to 8 wk had lower (13 to 24%) skeletal growth rates than controls. Large coral nubbins that were treated with estrone had thicker tissue. While the mech- anism for estrogen action for corals remains unknown, these experiments represent the first account of biological activity of steroidal estrogens in coral.

Estrogens and androgens are steroids that act as reproductive hormones in vertebrates. These compounds have also been detected in reef-building corals and other invertebrates, where they are hypothesized to act as bioregulatory molecules. Experiments were conducted using labeled steroid substrates to evaluate metabolism of estrogens and androgens by coral homogenates. GC-MS analysis of 13C-labeled steroids showed that Montipora capitata coral homogenates or fragments could convert estradiol to estrone and testosterone to androstenedione and androstanedione, evidence that M. capitata contains 17beta-hydroxysteroid dehydrogenase and 5alpha-reductase. When homogenates from three coral species and symbiotic dinoflagellates (zooxanthellae) were incubated with tritiated steroid substrates, metabolites separated by thin-layer chromatography confirmed that 17beta-hydroxysteroid dehydrogenase activity occurred in all species tested. NADP+ was the preferred cofactor in dehydrogenation reactions with coral homogenates. Reduction of estrone and androstenedione occurred at lower rates and aromatization of androgens was not observed. It is unclear whether estrogens detected previously in coral tissues are produced endogenously or sequestered in coral tissue from dietary or environmental sources. Previous studies have demonstrated that corals can take up estrogens from the water column overlying coral reefs. Considered in total, these observations suggest corals could alter the concentration or form of steroids available to reef organisms.

We measured rates of ammonium and phosphate uptake into 12 microatolls at One Tree reef lagoon, Australia, on 14 occasions over a range of seasonal and meteorological conditions from 1993 to 1995. Nine of the microatolls were spiked with ammonia and/or phosphate every low tide (2.5–4 h) during low- (15-month) and high- (13-month) loading periods. The remaining three microatolls that were not spiked with nutrient served as reference conditions. Ammonium concentrations were elevated from an average background of 0.7 to 11 µM NH4 during the low-loading period and 36 µM NH4 during the high-loading period, resulting in a loading to the benthos of 3.5 and 18 mmol NH4 m–2 low tide–1. Phosphate concentrations were elevated from an average background of 0.2 to 2.3 and 5.1 µM PO4 during low- and high-loading periods, respectively, resulting in a loading of 0.66 and 3.9 mmol PO4 m–2 low tide–1. Ammonium and phosphate concentrations decreased significantly over low-tides, and uptake rates were proportional to concentrations (first-order). The average uptake-rate constant, S (m s–1), for ammonium and phosphate did not differ between the two loading periods but was highly variable. Averaged over both loading periods, S for ammonium was 129±74×10–6 m s–1 and S for phosphate was 67±39×10–6 m s–1. At background nutrient concentrations, estimated nutrient-uptake rates were 7.8 mmol NH4 m–2 day–1 and 1.2 mmol PO4 m–2 day–1. Excretion rates—calculated from the mean difference in uptake rates measured in reference and nutrient-enriched microatolls—were estimated to be 4.3 mmol NH4 m–2 day–1 and 0.9 mmol PO4 m–2 day–1. We reason and suggest that nutrient uptake rates in these microatolls were close to mass-transfer limited rates. We conclude that nutrient uptake into coral reefs can be highly dynamic, varying 10-fold spatially and temporally.

The Biosphere 2 coral reef biome is a large, fully enclosed, self-sustaining mesocosm. Water is moved throughout the mesocosm by waves. Inorganic and organic nutrients were monitored weekly from 1995 to 2000. Eight nutrient-uptake experiments were conducted to measure uptake-rate constants (S, m s–1) for NH4, PO4, and NO3. Nutrient concentrations were low, except for DON, and typical of coral-reef ecosystems (means: NH4=0.63, NO3=0.62, PO4=0.05, SiO3=9.5, DON=41.2, DOP=0.26 mmol m–3). Nutrient uptake-rate constants varied in the range 54–126×10–6 m s–1 (4.6–11 m day–1) and correlated with water velocity. These rates, however, are 2–3-fold higher than rates for equivalent water velocities in steady, non-wave flows. Nutrients are recycled within the biome at rates sufficient to support gross production and, even in this recycling system, nutrient-uptake rates are mass transfer-limited.

Temperature, light and aragonite saturation state of seawater are important determinants of the global distribution of coral reefs. Saturation state of surface seawater is decreasing in response to increases in atmospheric pCO 2 , causing concern for a global reduction in the rates ol reef accretion. In this study we address the influences of light and saturation state on skeletal growth of the hermatypic coral Porites compressa. We conducted 2 experiments using coral nubbins; one in a controlled laboratory with Biosphere 2 ocean water and the other in the 711 m 2 Biosphere 2 ocean itself. The laboratory experiment consisted of 3 light treatments (PAR = 698, 150, 81 μmol photons m -2 s -1 ) and 2 chemical treatments (pCO 2 = 199 μatm, Ω = 5.05, CO 3 2- = 355 μmol kg -1 ; and pCO 2 = 448 μatm, Ω = 2.48, CO 3 2- = 183 μmol kg -1 ). In the Biosphere 2 ocean, coral nubbins were deployed at 4 depths (6, 4, 2 and 0.5 m) which corresponded to different light conditions (PAR from 2.7 to 29.5 mol photons m -2 d -1 ) during 3 different chemical states, mimicking the conditions of the Last Glacial Maximum (LGM), the present day and the year 2100 (Y2100). Calcification rate changed with light following the typical hyperbolic tangent function. Calcification rate was positively correlated with saturation state, which ranged from 5 (LGM) to 2.4 (Y2100). From the glacial experimental conditions (Ω = 5.05, pCO 2 = 186) to those of the future (Ω = 2.25, pCO 2 = 641), calcification dropped by 30%; from present day conditions (Ω = 3.64, pCO 2 = 336) to those of the future, calcification dropped by 11%, This decrease in calcification rate occurred at all light levels, indicating that rising CO 2 will impact corals living at all depths.

The concentration of CO2 in the atmosphere is projected to reach twice the preindustrial level by the middle of the 21st century. This increase will reduce the concentration of CO32− of the surface ocean by 30% relative to the preindustrial level and will reduce the calcium carbonate saturation state of the surface ocean by an equal percentage. Using the large 2650 m3 coral reef mesocosm at the BIOSPHERE-2 facility near Tucson, Arizona, we investigated the effect of the projected changes in seawater carbonate chemistry on the calcification of coral reef organisms at the community scale. Our experimental design was to obtain a long (3.8 years) time series of the net calcification of the complete system and all relevant physical and chemical variables (temperature, salinity, light, nutrients, Ca2+,pCO2, TCO2, and total alkalinity). Periodic additions of NaHCO3, Na2CO3, and/or CaCl2 were made to change the calcium carbonate saturation state of the water. We found that there were consistent and reproducible changes in the rate of calcification in response to our manipulations of the saturation state. We show that the net community calcification rate responds to manipulations in the concentrations of both Ca2+ and CO32− and that the rate is well described as a linear function of the ion concentration product, [Ca2+]0.69[CO32−]. This suggests that saturation state or a closely related quantity is a primary environmental factor that influences calcification on coral reefs at the ecosystem level. We compare the sensitivity of calcification to short-term (days) and long-term (months to years) changes in saturation state and found that the response was not significantly different. This indicates that coral reef organisms do not seem to be able to acclimate to changing saturation state. The predicted decrease in coral reef calcification between the years 1880 and 2065 A.D. based on our long-term results is 40%. Previous small-scale, short-term organismal studies predicted a calcification reduction of 14-30%. This much longer, community-scale study suggests that the impact on coral reefs may be greater than previously suspected. In the next century coral reefs will be less able to cope with rising sea level and other anthropogenic stresses.

The optimal conditioning regimen for allogeneic BMT for hematological malignancies is still to be determined. We used a conditioning regimen including high-dose Ara-C (HDAC)/CY/TBI for patients at high risk for leukemic relapse (regimen A, Ara-C 3 g/m2 every 12 h for six doses followed by CY 45 mg/kg for 2 days and TBI 13.2 Gy in eight fractions) and a standard CY/TBI conditioning regimen for patients at low risk (regimen B, CY 60 mg/kg for 2 days and TBI 13.2 Gy in eight fractions). We analyzed 55 patients treated with regimen A (group A) and 36 patients with regimen B (group B). Relapse rates (10.9% in group A, 2.9% in group B, P = 0.23), 5-year overall (53.2% in group A and 60.8% in group B, P = 0.26) and disease-free (47.7% in group A and 60.8% in group B, P = 0.11) survival rates were not significantly different between these groups, although group A consisted of high-risk patients. Regimen-related toxicities were not significantly different between the two groups. This result suggests that adding HDAC to CY/TBI conditioning regimen may reduce leukemic relapse and improve survival without increasing regimen-related toxicities.

A postal survey of 120 UK hospitals was conducted to assess the current use of filters in anaesthetic breathing systems and consultant anaesthetists' opinion of their value; 76% of the questionnaires were returned complete. The survey showed that 77.2% of anaesthetic departments use a new filter for every case, a variety of different filter types being used. A connector distal to the filter was used in 78.3% of patients, providing a possible route for cross infection. Anaesthetists rated the prevention of bacterial infection and gross contamination as being higher priorities than the prevention of viral infection. Of those surveyed, 66.3% believed filters were worthwhile whereas only 35.9% thought they were cost effective. Only 34.8% of anaesthetists believed that the supposed extra efficiency of pleated hydrophobic membrane filters over electrostatic filters merited their extra cost.

Both CO 2 chemistry and nutrient concentrations of seawater affect coral calcification. The relative effects of these factors on growth of corals were studied using coral tips or 'nubbins' of the hermatypic coral Porites compressa. Coral nubbins were grown over 5 wk in different combinations of pCO 2 (760 and 3980 μatm), HCO 3 - (1670 and 1520 μM), CO 3 2- (110 and 20 μM), and NO 3 - (0.42 to 5.66 μM). The pCO 2 was increased and CO 3 2- decreased by adding HCl to normal seawater; NO 3 - was increased by adding KNO 3 to ambient seawater. Corals growing in seawater at a reduced pH of 7.2 calcified at half the rate of control corals at pH 8.0, indicating that coral growth is strongly dependent on the concentration of CO 3 2- ions in seawater. Reduction of calcification from lowered pH and CO 3 2- was greater than reduction from nitrate additions. Corals in low pH treatments recovered their initial calcification rates within 2 d of re-introduction to ambient seawater, indicating the effects of CO 2 chemistry are immediate and reversible. Changes in calcification from increases in atmospheric CO 2 , and hence decreases in CO 3 2- , may be larger than local effects from elevated nutrients.

Spawnings of scleractinian corals are affected by light, temperature, and other environmental cues, but no studies elucidate physiological mechanisms that regulate coral gametogenesis. We hypothesized that estrogens may act as bioregulators of coral reproduction. Estrone (E1) and estradiol-17 beta (E2) concentrations were measured in homogenates of tissue and skeleton from M. verrucosa. Tissue samples were collected monthly throughout the year, and more frequently in July and August around spawning. Steroids were extracted with diethyl ether, purified via celite chromatography and assayed with radioimmunoassay. Non-specific binding in coral tissue varied with sample weight and was elevated relative to standards. Monthly mean E1 ranged from 20-70 ng E1 g ash-free dry weight (AFDW)-1, with highest values in April. Smaller asynchronous peaks occurred in early July, prior to spawning. Monthly mean E2 ranged from 8-25 ng E2 g AFDW-1, with highest values in February and March. Peaks in E2 preceded peaks in E1, indicating metabolism of a pool of estrogen. E1 was positively correlated with protein concentration, which is consistent with a bioregulatory role of estrogens. Estrogen peaks in spring and prior to the July spawn corroborate our hypothesis that estrogens regulate coral gametogenesis and spawning.

This paper examines the implications for lifetime income equality of alternative retirement income arrangements, using the Australian scheme as a benchmark. In Australia, the pay-as-you go financed age pension is means-tested and thereby provides a contrast with those countries where part or all of a basic pension is paid to all aged persons. Many governments are considering an increase in the level of means-testing. The results show that the introduction of a universal pension coupled with significant changes and simplifications to the structure of taxation and superannuation have little effect on the redistributive impact of the tax structure in a life cycle framework. The presence of means-testing appears to have no significant effect on life-time inequality. The results suggest that it is possible to eliminate complexities from the system providing retirement benefits without having any deleterious effect on equity.

Captive whitetip reef sharks, Triaenodon obesus,at Sea Life Park (SLP) Hawaii, Waimanalo, Hawaii develop goitre, whereas, T. obesus at the Waikiki Aquarium (WAQ), Honolulu,Hawaii do not develop goitre. To determine theeffects of natural concentrations of iodine on thereduction of goitre, two sharks from SLP with goitrewere placed in an enclosed coastal lagoon with naturalseawater. Using ultrasound measurements the twogoitres were initially 11.4 cm and 14.6 cm in depthand after 3 months decreased to 4.7 cm and 5.7 cm. Radioimmunoassay analysis of the thyroid hormoneT3 sera concentrations were initially 0.22 ng/mland 0.33 ng/ml and increased to 1.84 ng/ml after beingplaced in the lagoon. Sera T4 were initially0.93 ng/ml and 0.99 ng/ml and increased dramaticallyto 17 ng/ml and 56 ng/ml. Over the six month samplingperiod, two resident sharks in the lagoon with normalthyroids had sera T3 concentrations from 0.89ng/ml to 1.1 ng/ml, and sera T4 concentrationsfrom 3.1 ng/ml to 7.9 ng/ml. The hypothyroidcondition in the SLP goitred-sharks is likely linkedto the low environmental iodide (

The uptake of nutrients (N and P) into coral reef communities is proposed to be limited by diffusion through concentration-depleted boundary layers between the water and organisms, or what is termed “mass transfer limitation.” The mass transfer rate is a physical limit to the rate of nutrient uptake. Maximum uptake rates by highly rough biological surfaces have not yet been evaluated. Engineering correlations indicate that increased surface roughness should increase mass transfer, although it has been difficult to quantify roughness of living corals. In this paper, the effects of highly rough coral surfaces on mass transfer were investigated by using dissolution of gypsum (Plaster-of-Paris) from flat smooth surfaces and coral skeletons. The gypsum dissolution rates were mcasurcd as an increase in concentration of calcium ions in freshwater recirculating over experimental surfaces. Stanton numbers (St,,,, a dimensionless number giving the ratio of uptake rate per unit area to the rate of advection of the substance past the uptake surface) of experimental smooth surfaces ranged from 2.6 to 3.5 X lo-’ and were the same as values in the engineering literature for smooth surfaces. St,,, for coral-shaped surfaces ranged from 70 X 10. ’ at 0.03 m s-l to 17 X 10 5 at velocities up to 0.50 m s-l and were in general 9 & 1 times that of smooth surfaces. The measured St,,, for each coral-shaped surface was the same as the predicted St,,, (+ 10%) calculated from measured friction and roughness using a correlation of heat transfer. St,,, for ammonia uptake on living coral reef communities show the same relationship between mass transfer, friction, and roughness as the coral-shaped gypsum surfaces. The transport rates of nutrients to reef surfaces are controlled by large-scale roughness, typically associated with coral heads, and not small-scale roughness elements on the organisms, nor biological alterations of diffusive boundary layers. Nutrient uptake and possibly other metabolic exchange rates arc governed by concentration, water velocity, and friction dissipated over the reef, denoting that coral reef community metabolism is physically forced. Uptake rates of nutrients (PO,, NH,) to assemblages of coral-reef benthos are positively correlated with the velocity of water flowing over the assemblage (Atkinson and Bilger 1992; Atkinson et al. 1994; Bilger and Atkinson 1995; Thomas and Atkinson 1997). These authors explained this observation by hypothesizing that the rate-limiting step for nutrient uptake is diffusion of nutrient ions through nutrientdepleted diffusive boundary layers adjacent to the surface of the benthos, termed mass-transfer limitation (Bilger and Atkinson 1992). Nutrient-uptake rate of coral-reef benthos, m,, (mol m-* s-l, where m-* is the projected planar area of the bottom), is described as a first-order rate reaction with respect to the concentration gradient through the boundary layer: m, = SW, - GA

Insulin-Dependent Diabetes (IDD) results from an autoimmune destruction of the insulin secreting pancreatic beta cells. The immunological mechanisms underlying the development of IDD as well as the role of environmental agents (e.g., diet, viruses, stress) in the pathogenesis of the disease are the subject of considerable research efforts. Significant attention has recently been directed to a hypothesis that consumption of cows' milk in infancy may trigger the autoimmune process underlying IDD. Early evidence supporting this "cows' milk hypothesis" included case-control studies surveying infant nutrition practices (i.e., breast feeding versus consumption of infant formula) and the subsequent development of IDD. However, intense media interest surrounding a report indicating anti-bovine serum albumin (BSA) immunity as the cause of IDD has lead to heightened public awareness of the issue, and, together with the epidemiological data, prompted The American Academy of Pediatrics to modify its guidelines for infant feeding practices. However, less public and scientific attention has been given toward the observations that many of these case-control studies were retrospective in design and subject to recall bias, narrow in scope in terms of collecting dietary information, and that similar results have not been duplicated in other more recent (and better designed) investigations. Furthermore, the immunological report implicating anti-BSA immunity with the disease has become controversial due to difficulties in conforming the findings, and experiments in animal models closely resembling human IDD have not uniformly supported a role for anti-BSA immunity in the pathogenesis of IDD. Given the significant morbidity and mortality associated with IDD, an improved understanding of the cause of this disorder as well as identifying possible methods for its prevention are essential. However, without additional supporting information, modification of the cows' milk/BSA composition of diets in order to avoid the disease may be premature. Further studies are needed to clearly establish a role for diet in the pathogenesis of IDD.

To test the hypothesis that ammonium uptake by coral reefs is mass-transfer limited and to determine the relative effects of water velocity and community roughness on uptake, we measured the rates of ammonium uptake by reefs at velocities ranging from 3.3 to 37.5 cm s -1 . Two assemblages of coral rubble (relatively rough and relatively smooth) and two assemblages of live coral (Porites compressa and Pocillopora damicornis) were used. Rate constants for uptake ranged from 16 to 144X 10 -6 m s -1 and were positively correlated to water velocity. We estimated roughness of each assemblage as mean height, relief, and by measuring the friction coefficient of each assemblage at water velocities ranging from 3.3 to 58.0 cm s -1 . Friction coefficients ranged from 0.033 to 0.264. Stanton numbers (a dimensionless ratio of uptake rate to advection past the uptake surface) calculated from experimental data were within 80% of those calculated from empirically derived engineering equations describing heat transfer to rough surfaces. Results support the hypothesis that ammonium uptake is mass-transfer limited and are consistent with mass transfer relationships for nonbiotic surfaces.

To measure the effects of pressure on the output of a membrane oxygen sensor and a nonmembrane oxygen sensor, the authors pressure cycled a CTD sensor package in a laboratory pressure facility. The CTD sensor package was cycled from 30 to 6800 db over a range of temperatures from 2° to 38°C. Pressure decreased the output of the membrane sensor and increased the output of the microhole sensor. The pressure terms for both types of oxygen sensors were affected by temperature. The effect of pressure on both types of sensors can be quantified as exp (VP/R′T), where V is a coefficient (cm3 mol−1), P is decibars, R′ is the gas constant (831.47 cm3 mol−1 db K−1), and T is kelvins. As water gets colder, V for both sensors increases. For temperatures less than 21°C, V for the membrane sensor is −33.7±0.54 cm3 mol−1, and V for the microbole sensor is 0.29±0.31 cm3 mol−1. The V's for calibrations of four oceanic casts had larger ranges than the laboratory experimental data: −27.6 to −34.9 cm3 mol−1 for the m...

This paper compares the lifetime redistribution and progressivity, within a cohort of males, of two retirement income systems. The current government strategy in Australia is to increase the role of occupational superannuation and maintain a means-tested age pension. The Institute of Actuaries of Australia has recommended a universal pension with a corresponding smaller role for occupational superannuation. In terms of lifetime inequality and progressivity measures, it is found that there is not a substantial difference between the two systems. Other issues, such as the benefit choice at retirement and differential mortality, are found to be more important in determining the lifetime redistributive impact of a retirement income strategy.

Fifty-seven species of hermatypic corals have been maintained and grown in high-nutrient seawater at the Waikiki Aquarium, Honolulu, Hawaii. In this study we document the chemical conditions of aquarium water in terms of dissolved nutrients and carbon. Aquarium water is characterized by concentrations of inorganic nutrients that are high relative to most natural reef ecosystems: SiO3 ∼200 μM; PO4 ∼0.6 μM; NO3 ∼5 μM; NH4 ∼2 μM. In contrast, concentrations of organic nutrients are lower than most tropical surface ocean waters: DOP ∼0.1 μM and DON ∼4 μM. The incoming well-water servicing the facility has low pH, creating over-saturation of carbon dioxide. The coral communities in aquaria took up inorganic nutrients and released organic nutrients. Rates of nutrient uptake into aquaria coral communities were similar to nutrient uptake by natural reef communities. Coral growth rates were near the upper rates reported from the field, demonstrating corals can and do flourish in relatively high-nutrient water. The growth of corals does not appear to be inhibited at concentrations of nitrogen up to 5 μM. Statements implying that corals can only grow in low nutrient oligotrophic seawater are therefore over-simplifications of processes that govern growth of these organisms. Some basic guidelines are given for maintenance of coral communities in aquaria.

Individual retirees face a daunting task when they consider how best to invest their accumulated superannuation account and non-superannuation savings. This article highlights the fact that there is rarely an obvious decision in this choice and that the optimal decision depends on a number of factors. These factors include the valuation criterion adopted, the level of benefits, the individual's income level, the means-tests, the tax rates on income and superannuation benefits and the person's life expectancy. The optimal behaviour at retirement is significantly affected by the individual characteristics of relative lifetime earnings and post-retirement rates of mortality.

Response characteristics of a microhole potentiostatic oxygen sensor and a Beckman membrane oxygen sensor were measured in a laboratory over temperatures ranging from 1° to 21°C. The response term τ of the microhole sensor changed 1.7-fold over this temperature range, and τ of the membrane sensor changed 1.6-fold. For the microhole sensor, the effect of temperature on τ can be modeled as lnτ+−6.5 + 1618T−1. For the membrane sensor the temperature effect on τ can be modeled as lnτ = −5.8 + 2116T−1, where T is temperature in kelvins.

A non-membrane, micro-hole, potentiostatic oxygen sensor was designed and tested for use on an oceanic CTD. The sensor consists of three electrodes: a carbon-fiber cathode, a Ag/ AgC1 reference and a platinum anode; all are mounted in a plexiglass flow duct. The carbon-fiber cathode is a bundle of 1000 carbon fibers recessed in epoxy and electroplated with platinum. The sensor calibrates to oxygen concentration (02), not partial pressure. The effect of temperature on sensor output can be modelled with an activation energy term. Pressure decreases current output of these sensors 5% over 5000 dbar. Ten calibration casts were performed as part of the Hawaii Ocean Time Series (HOTS) sampling program in the Pacific Ocean north of Oahu, Hawaii. Vertical profiles of O2 were calibrated using 18–23 Winkler determinations from each cast. The coefficient of determination (r2) for the calibrations ranged from 0.9979 to 1.0000. The standard deviation of the unexplained error between predicted O2 and Winkler OZ ranged from 0.49 to 3.6 μM, with a mean value of 1.3 μM.

Dynamic subclass checks are common in many sub-paradigms of object-oriented programming. These checks may be simply implemented by following the superclass chain through the objects which represent the class hierarchy. However, in large or data-intensive applications, such as OODBMS, this simple checking strategy may have significant efficiency consequences. Very long class chains, which commonly occur, can cause much pointer following, which in turn has a knock-on effect on the overall performance of memory management. Measurements have shown that memory management is the most significant factor in the performance of large object-oriented systems.This paper describes a way of testing if one class is a subclass of another without involving any pointer accesses. On creation, each class is allocated a unique pair of integers, over which subclass tests may be performed using only arithmetic. The technique only works for single inheritance systems; the essence of the technique is to simulate the tree structure of the class hierarchy using the well-understood mathematical model of continued fractions.

A 23-year-old Brazilian, or lowland, tapir with a 6-month history of loss of body condition developed clinical signs and laboratory findings consistent with liver failure. The animal was euthanased and a diagnosis of hepatic haemochromatosis was made based on histopathology. Two other healthy tapirs in the same collection had chronically elevated serum and tissue iron concentrations. The excessive accumulation of iron in tissues with resultant tissue damage (i.e. haemochromatosis) has been reported in a range of captive species. This and other reported cases of haemochromatosis in the Brazilian tapir would suggest that this condition is an important consideration in the management of this species in zoos. Further research into the endogenous regulation of iron metabolism, especially the role of hepcidin, in tapirs and other species at risk of iron storage disorders may be helpful in the prevention of this condition.

Type I procollagen secreted by dermal fibroblasts from an individual with osteogenesis imperfecta type IV was a mixture of normal molecules and molecules that were post-translationally overmodified. The individual was heterozygous for a G to A transition in the COL1A1 gene that resulted in the substitution of serine for glycine 883 in one or both of the pro alpha 1 (I) chains. The thermal stability of molecules containing overmodified chains was lower by 2 degrees C than that of normal molecules. However, following cleavage of the molecules with vertebrate collagenase, the temperature of denaturation of the overmodified A fragments (residues 1-775 of the helix did not contain the substitution) was 2 degrees C greater than that of A fragments from normal molecules. The rates of cleavage by procollogen N-proteinase (EC 3.4.214.14) (N-proteinase) of procollagen molecules in normal and osteogenesis imperfecta samples were not significantly different. The procollagen molecules in the osteogenesis imperfecta sample were also indistinguishable from those in control samples by rotary shadowing electron microscopy. The results suggest that this substitution of serine for glycine in the alpha 1 (I) chain of procollagen, like the substitution of aspartate for the same glycine previously described (Lightfoot, S. J., Holmes, D. F., Brass, A., Grant, M. E., Byers, P. H., and Kadler, K. E. (1992) J. Biol. Chem. 267, 25521-25528), can alter the structure of the triple helix N-terminal to the site of the substitution. However, in contrast to the aspartate for glycine substitution, the structural change is insufficient to delay the cleavage of the procollagen by N-proteinase and results in a mild rather than lethal phenotype.

The first enzyme of the Bacillus subtilis histidine-degradative (hut) pathway, histidase, was expressed at higher levels during the onset of the stationary growth phase in nutrient sporulation medium in early-blocked sporulation mutants (spo0A) than in wild-type strains. Histidase expression was also elevated in spo0A mutant cultures compared with wild-type cultures during the logarithmic growth phase in minimal medium containing slowly metabolized carbon sources. Histidase expression was not derepressed in spo0A abrB mutant cultures under these growth conditions, suggesting that the AbrB protein is responsible for the derepression of histidase synthesis seen in spo0A mutant cultures. spo0A mutants contain higher levels of the AbrB protein than do wild-type strains because the Spo0A protein represses AbrB expression. A direct correlation between the levels of abrB transcription and histidase expression was found in spo0A mutant cultures. The hutOCR2 operator, which is required for wild-type regulation of hut expression by catabolite repression, was also required for AbrB-dependent derepression of hut expression in spo0A mutants. Purified AbrB protein bound to the hutOCR2 operator in vitro, suggesting that AbrB protein alters hut expression by competing with the hut catabolite repressor protein for binding to the hutOCR2 site. During the logarithmic growth phase in media containing slowly metabolized carbon sources, the expression of several other enzymes subject to catabolite repression was elevated in spo0A mutants but not in spo0A abrB mutants. This suggests that the AbrB protein acts as a global modulator of catabolite repression during carbon-limited growth.

Background: The purpose of the study was to determine the prevalence and associations of clinically relevant fatigue (CRF) in men with biochemically controlled prostate cancer on long-term androgen deprivation therapy (ADT). Patients and methods: One hundred and ninety-eight men were surveyed and the prevalence of CRF (Brief Fatigue Inventory score >3) determined. Associations with other measures (Hospital Anxiety and Depression Scale; International Prostate Symptom Score; European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire; Brief Pain Inventory worst pain; clinical and demographic information) were explored in univariate and multivariate analyses. Results: Eight-one per cent (160 of 198) of questionnaires were analysable. CRF prevalence was 43% (68 of 160). CRF associations included moderate/severe urinary symptoms, anxiety and medical co-morbidities; the strongest associations were depression [odds ratio (OR) 9.8, 95% confidence interval (CI) 4.3-22.8] and pain (OR 9.2, 95% CI 4.0-21.5). After controlling for other factors, the independent associations were depression (OR 4.7, 95% CI 1.6-14.0) and pain (OR 3.1, 95% CI 1.0-8.9). There was no association with age, disease burden or treatment duration. Conclusions: Two-fifths of men with biochemically controlled prostate cancer on long-term ADT report CRF that interferes with function. Management aimed at improving CRF should address depression and pain. © The Author 2011. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved.

Osteoarthrosis is a common disorder of synovial joints, seen most often in older patients. The joints affected most commonly are the knee, hip, hands and the first metatarsophalangeal joint. Involvement of other joints such as the ankle, wrist and shoulder is uncommon, and suggests a secondary etiology. Although osteoarthrosis may be present in many joints, symptoms are usually evident in one or two joints at the most. The three main symptoms are pain, morning stiffness and a tendency for the affected joint to gel with immobility. Treatment includes rest; weight loss; physiotherapy; aids such as canes, shoe lifts, and elastic knee supports; and judicious use of anti-inflammatory medications.

During growth of Bacillus subtilis in nutrient sporulation medium containing histidine (DSM-His medium), the expression of histidase, the first enzyme in the histidine-degradative pathway (hut), is derepressed 40- to 200-fold at the onset of stationary phase. To identify the gene products responsible for this regulation, histidase expression was examined in various hut regulatory mutants as well as in mutants defective in stationary-phase gene regulation. Histidase expression during growth in DSM-His medium was significantly altered only in a strain containing the hutC1 mutation. The hutC1 mutation allows the hut operon to be expressed in the absence of its inducer, histidine. During logarithmic growth in DSM-His medium, histidase levels were 25-fold higher in the HutC mutant than in wild-type cells. Moreover, histidase expression in the HutC mutant increased only four- to eightfold after the end of exponential growth in DSM-His medium. This suggests that histidine transport is reduced in wild-type cells during exponential growth in DSM-His medium and that this reduction is largely responsible for the repression of hut expression in cells growing logarithmically in this medium. Indeed, the rate of histidine uptake in DSM-His medium was fourfold lower in exponentially growing cells than in stationary-phase cells. The observation that the degradation of histidine is inhibited when B. subtilis is growing rapidly in medium containing a mixture of amino acids suggests that a hierarchy of amino acid utilization may be present in this bacterium.

The detection, prevention and treatment of disease is greatly facilitated by the availability of accurate and non-invasive techniques for measuring the amount and regional distribution of fat mass and fat-free mass. As differing degrees of hydration may influence these measurements, we used dual-energy X-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA) to detect changes in hydration following hemodialysis, and to determine whether fat mass, fat-free mass and bone density measurements were affected by these fluid changes. Ten subjects (7 men, 3 women) mean age 46.2 years (range 25–68 years), with renal failure had bone density, fat-free mass and fat mass measured by DXA, and total body water and fat-free mass measured by BIA, before and after hemodialysis. Thirty-two subjects had fat-free mass measured by DXA and BIA in an attempt to derive new equations (using fat-free mass measured by DXA as the reference standard) to improve the predictive value of BIA. The new equations were then used to derive the changes in fat-free mass following hemodialysis measured using BIA. In absolute terms, total tissue measured by DXA (r=0.99,p=0.01) and total body water measured by BIA (r=0.91,p=0.01) correlated with gravimetric weight. Following hemodialysis, fat mass and bone density measured by DXA were unaffacted by the fluid changes. The change in gravimetric weight was 1.8±0.3 kg,p=0.01 (mean±SEM). This change was measured as 1.9±0.3 kg by DXA, −0.9±1.0 kg by BIA using the published equation for fat-free mass, and 3.2±0.4 kg using the new equation for fat-free mass. The change in fat-free mass measured by DXA (r=0.75,p=0.01), and the change in total body water measured by BIA (r=0.70,p=0.02), correlated with the change in gravimetric weight. The change in fat-free mass measured by BIA did not correlate with the change in gravimetric weight. With the new equation, the change in fat-free mass measured by BIA correlated with the change in gravimetric weight (r=0.74,p=0.02). We conclude that absolute values, and changes in fluid in the range observed in this study, can be detected reliably by DXA. They are reflected in the fat-free mass measurement and do not confound measurements of fat mass and bone density. Although absolute values are reliably measured by BIA, the technique may have limited usefulness in detecting fluid changes. DXA thus provides a practical, non-invasive, precise and accurate method of measuring body composition which can be used as a ‘gold standard’ for validating other techniques.

Our previous studies showed that high levels of soluble CD25 (sCD25) in the serum of patients with hepatocellular carcinoma (HCC) correlated with blunted effector T-cells (Teff) responses, tumour burden and poor survival. Understanding the interactions between Teff, CD4+CD25+ regulatory T cells (Treg) and soluble factors can identify novel therapeutic targets. In this study, we characterize the mechanisms by which HCC serum and sCD25 mediate suppression of Teff and evaluate the effect of sCD25 on the suppression assays with normal healthy control cells (NHC) at a 1:1 Treg to Teff cell ratio to determine whether sCD25 has any impact on Treg suppression. HCC serum and sCD25 suppressed Teff proliferation and downregulated CD25 expression on HCC Teff in a dose-dependent fashion with sCD25 doses above 3000 pg/ml. Treg from HCC and cirrhosis patients suppressed proliferation of target CD4+CD25- Teff in serum-free medium (SFM). HCC Treg showed a higher degree of suppression than cirrhosis-derived Treg. In contrast, Treg from NHC did not suppress target Teff in SFM. However, isolated Treg from all three study subjects (HCC, cirrhosis and NHC) suppressed CD4+CD25- Teff in serum conditions or in the presence of sCD25 in the range 6000-12,000 pg/ml. In conclusion, downregulation of CD25 cell surface expression on Teff is part of the overall suppressive mechanism of sCD25 and HCC serum on Teff responses. The observed sCD25 and HCC serum-mediated suppression is further influenced via novel immune-inhibitory interaction between CD4+CD25+ Treg and sCD25.

Nonarticular rheumatism refers to a group of conditions characterized by musculoskeletal aches and pains which do not arise from joints. A number of different entities are considered under this definition. They are classified either as generalized conditions which include polymyalgia rheumatica, fibrositis and aches and pains NYD, or localized conditions which include the enthesopathies: tendonitis, epicondylitis and fasciitis, tenosynovitis and bursitis. The treatment of most of these conditions is expectant, because they tend to be self-limiting and improve despite therapeutic interventions. The exception is polymyalgia rheumatica, which requires low dose steroids for a varying period of time—sometimes years.