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The effects of elevated CO2 and temperature on photosynthesis and calcification of two important calcifying reef algae (Halimedamacroloba and Halimeda cylindracea) were investigated with O2 microsensors and chlorophyll a fluorometry through a combination of two pCO2 (400 and 1,200 μatm) and two temperature treatments (28 and 32 °C) equivalent to the present and predicted conditions during the 2100 austral summer. Combined exposure to pCO2 and elevated temperature impaired calcification and photosynthesis in the two Halimeda species due to changes in the microenvironment around the algal segments and a reduction in physiological performance. There were no significant changes in controls over the 5-week experiment, but there was a 50-70 % decrease in photochemical efficiency (maximum quantum yield), a 70-80 % decrease in O2 production and a threefold reduction in calcification rate in the elevated CO2 and high temperature treatment. Calcification in these species is closely coupled with photosynthesis, such that a decrease in photosynthetic efficiency leads to a decrease in calcification. Although pH seems to be the main factor affecting Halimeda species, heat stress also has an impact on their photosystem II photochemical efficiency. There was a strong combined effect of elevated CO2 and temperature in both species, where exposure to elevated CO2 or temperature alone decreased photosynthesis and calcification, but exposure to both elevated CO2 and temperature caused a greater decline in photosynthesis and calcification than in each stress individually. Our study shows that ocean acidification and ocean warming are drivers of calcification and photosynthesis inhibition in Halimeda. Predicted climate change scenarios for 2100 would therefore severely affect the fitness of Halimeda, which can result in a strongly reduced production of carbonate sediments on coral reefs under such changed climate conditions. © 2012 Springer-Verlag.

Entacmaea quadricolor is a geographically widespread species of sea anemone that forms a three-way symbiosis with anemonefish and Symbiodinium. This species dominates the reef substrata at North Solitary Island, Australia, which is located in a region identified as a climate change hot spot. Their geographic location places these anemones under significant threat from rising ocean temperatures, although their upper thermal limit and risk of bleaching are unknown. To address this knowledge gap, anemones were exposed to one of four temperatures (23, 25, 27, or 29 degrees C) and one of two irradiance treatments (high or low light) over 6 days. At moderate temperatures (27 degrees C, 1 degrees C above summer average), anemone bleaching was characterised by symbiont expulsion, while extreme temperatures (29 degrees C) resulted in an additional loss of photosynthetic pigments from within symbionts, and in some cases, host mortality. Irradiance influenced the susceptibility to thermal stress with high light promoting the bleaching response, along with significant reductions in the effective quantum yield of anemone symbionts. The long-term loss of photosystem II photochemical efficiency within in hospite symbionts was observed during exposure to temperatures exceeding the summer average, indicating photosynthetic damage. The resident Symbiodinium, identified as clade C using 28S rRNA gene sequences, therefore represents the partner within the symbiosis that is likely to be most vulnerable to rising seawater temperatures. Results suggest that E. quadricolor is living within approximately 1 degrees C of the upper thermal maximum at the Solitary Islands, and given the predictions for rising seawater temperature on Australia's east coast, the thermal threshold at which bleaching will occur is expected to be reached and exceeded more frequently in the future.

The study was designed to examine sport interest in a sample of male and female university students in order to determine if the personality measures of competitiveness, instrumentality, expressivity, and sensation seeking are predictive of sport interest as well as sport participation in a variety of sports. Factor analysis of Franken's WCMP Scale (a scale that contains a variety of questions pertaining to winning, competitiveness, mastery, and persistence) produced three factors that were named: the Motivation for High Performance Scale (MHP), the Motivation for New Learning Scale (MNL), and the Importance of Winning Scale (WIN). The emergence of the MHP and WIN as distinct factors was taken as evidence for the idea that sometimes people seek out competition in order to perform at a high level or observe others perform at a high level while at other times people seek out competition in order to be a winner of observe others as winners. MHP was the best predictor of sport interest for both males and females although WIN, the Competitiveness Scale of Spence and Helmreich's Work and Family Orientation Questionnaire (WOFO), and Instrumentality were also good predictors for certain sports. MNL, the Mastery Scale of the WOFO, and Expressivity were significant predictors of sport interest but mainly in connection with female interest in figure skating and gymnastics. Sensation seeking was not a predictor of sport interest although certain subscales of Zuckerman's Sensation Seeking Scale did predict sport interest in certain instances. Analysis of sex differences indicated that female as compared to male participants were significantly more interested in gymnastics and figure skating, whereas male as compared to female participants were significantly more interested in hockey, football, baseball and basketball, golf, tennis, and boxing. Males obtained higher scores on all of the personality measures used except expressivity (where females scored significantly higher).

The effects of elevated CO2 and temperature on photosynthesis and calcification in the calcifying algae Halimeda macroloba and Halimeda cylindracea and the symbiont-bearing benthic foraminifera Marginopora vertebralis were investigated through exposure to a combination of four temperatures (28°C, 30°C, 32°C, and 34°C) and four CO2 levels (39, 61, 101, and 203 Pa; pH 8.1, 7.9, 7.7, and 7.4, respectively). Elevated CO2 caused a profound decline in photosynthetic efficiency (FV: FM), calcification, and growth in all species. After five weeks at 34°C under all CO2 levels, all species died. Chlorophyll (Chl) a and b concentration in Halimeda spp. Significantly decreased in 203 Pa, 32°C and 34°C treatments, but Chl a and Chl c2 concentration in M. vertebralis was not affected by temperature alone, with significant declines in the 61, 101, and 203 Pa treatments at 28°C. Significant decreases in FV: FM in all species were found after 5 weeks of exposure to elevated CO2 (203 Pa in all temperature treatments) and temperature (32°C and 34°C in all pH treatments). The rate of oxygen prod°Ction declined at 61, 101, and 203 Pa in all temperature treatments for all species. The elevated CO2 and temperature treatments greatly reduced calcification (growth and crystal size) in M. vertebralis and, to a lesser extent, in Halimeda spp. These findings indicate that 32°C and 101 Pa CO2, are the upper limits for survival of these species on Heron Island reef, and we conclude that these species will be highly vulnerable to the predicted future climate change scenarios of elevated temperature and ocean acidification. © 2011, by the American Society of Limnology and Oceanography, Inc.

Global climate change is leading to the rise of ocean temperatures and is triggering mass coral bleaching events on reefs around the world. The expulsion of the symbiotic dinoflagellate algae is believed to occur as a result of damage to the photosynthetic apparatus of these symbionts, although the specific site of initial impact is yet to be conclusively resolved. Here, the sensitivity of the oxygen evolving complex (OEC) to bleaching stress was studied as well as its natural variation between seasons. The artificial electron donor, diphenyl carbazide (DPC), was added to cultured, freshly isolated and expelled (bleaching treatments only) zooxanthellae suspensions. Chl a fluorescence and oxygen production measurements showed that upon addition of DPC, no restoration of diminished photochemical efficiency occurred under control or bleaching conditions. This result was consistent between 12 h and 5 d bleaching treatments on Pocilloporadamicornis, indicating that the OEC is not the primary site of damage, and that zooxanthellae expulsion from the host is a nonselective process with respect to the functioning of the OEC. Further experiments measuring fast induction curves (FICs) revealed that in both summer and winter, the temperature when OEC function was lost occurred between 7°C and 14°C above the sea surface temperature. FIC and oxygen production measurements of P. damicornis during exposure to bleaching stress demonstrated that the thermotolerance of the OEC increased above the temperature of the bleaching treatment over a 4 h period. This finding indicates that the OEC has the capacity to acclimate between seasons and remains functional at temperatures well above bleaching thresholds. © 2008 Phycological Society of America.

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Just as synthetic seismic data can be created by expressing the wave field radiating from a seismic source as a set of Gaussian beams, recorded data can be downward continued by expressing the recorded wave field as a set of Gaussian beams emerging at the earth’s surface. In both cases, the Gaussian beam description of the seismic‐wave propagation can be advantageous when there are lateral variations in the seismic velocities. Gaussian‐beam downward continuation enables wave‐equation calculation of seismic propagation, while it retains the interpretive raypath description of this propagation. This paper describes a zero‐offset depth migration method that employs Gaussian beam downward continuation of the recorded wave field. The Gaussian‐beam migration method has advantages for imaging complex structures. Like finite‐difference migration, it is especially compatible with lateral variations in velocity, but Gaussian beam migration can image steeply dipping reflectors and will not produce unwanted reflections from structure in the velocity model. Unlike other raypath methods, Gaussian beam migration has guaranteed regular behavior at caustics and shadows. In addition, the method determines the beam spacing that ensures efficient, accurate calculations. The images produced by Gaussian beam migration are usually stable with respect to changes in beam parameters.

Coral bleaching events have been linked to elevated seawater temperatures in combination with intense light and can be characterised by the loss of symbionts (zooxanthellae, genus Symbiodinium) from the host tissue, as well as a reduction in photosynthetic pigments in these zooxanthellae. The long-term (days) viability of expelled zooxanthellae in the water column from the scleractinian coral Pocillopora damicornis was explored in this study through measurements of photosynthetic health and morphological condition. After initial expulsion, zooxanthellae were found to be photosynthetically competent and structurally intact. However, within 6 to 12 h following this time, photosystem II photochemical efficiency dramatically declined in these cells and photosynthetic damage was gradually manifested in the loss of structural integrity of the cell. The time of expulsion during bleaching exposure, as well as ambient water temperature, greatly influenced survivorship. Expelled zooxanthellae were collected at 4 different time intervals (0-6, 6-12, 12-24 and 24-36 h) following the onset of exposure to bleaching conditions (32°C and 400 μmol photons m-2 s-1) and then maintained at 28, 30 or 32°C and 100 μmol photons m-2 s-1 for up to 96 h. Those cells expelled within the first 6 h of bleaching and held at 28°C (lagoon temperature) had the greatest longevity, although even in this treatment, long-term photosynthetic viability was restricted to 5 d in the water column. This suggests that unless expelled zooxanthellae inhabit other environments of coral reefs (such as sediments) which may be more favourable for survival, their capacity for persistence in the environment is extremely limited. © Inter-Research 2007.

The effect of diel oscillations in light on the photosynthetic response of three coral species during summer and winter was studied. Fast induction curves revealed detailed information on primary photochemistry as well as redox states of electron acceptors in photosystem II (PSII). The comparison between seasons revealed that similar physiological mechanisms were operating in response to high-light conditions throughout the year and that environmental variables, such as temperature, had no measurable effect between seasons. A diurnal hysteresis was seen in both seasons in Fv / Fm as well as in the fast induction curves, where photosynthetic capacity was lower in the afternoon than in the morning when light intensities were the same. This suggests the operation of dynamic down regulation, following exposure to midday high light. Fast induction curve analysis revealed a decline in the O, J, I and P steps towards midday and a rapid recovery by the late afternoon. The decrease in J and its rapid recovery indicated a drop in the rate of QA reduction as a result of an increase in non-photochemical quenching (NPQ). The P step increased in amplitude in the first hours of sunlight, which suggests an increased oxidation of the plastoquinone (PQ) pool and a greater capacity for electron transport. Similarly, a rise in Fv / Fm was observed within the first hour of sunlight. This response was attributed to the dark reduction of the PQ pool, induced by night time anaerobic conditions and possibly oxygen-dependent chlororespiration, which would lead to a state 2 transition. The early morning removal of chlororespiration and hypoxic conditions would have returned the photosystems to state 1, resulting in the increased photochemical efficiency of the zooxanthellae.

Tube-building annelid worms from the family Serpulidae (Fig. 1) significantly contribute to calcium carbonate deposition on temperate reefs. These frame-builders modify the physical environment and enhance biodiversity by providing shelter, food and substrate (Bosence 1979). Despite their ecological importance, there has been little research into the skeletal carbonate mineralogy of serpulid worm tubes, with the limited available data originating from the northern hemisphere (Bornhold and Milliman 1973; Vinn et al. 2008). Characterising the potential for mineralogical variation in skeleton calcification within an individual, between species or over a temporal scale would be especially useful in understanding how serpulids will respond to environmental change. A major threat to marine calcifiers is ocean acidification where shifts in ocean carbonate chemistry will reduce the ability for growth, weaken tube integrity and potentially lead to skeletal dissolution in serpulids (Chan et al. 2012). Given their role in shaping many temperate marine ecosystems and their vulnerability to environmental change, the study by Smith et al. (2013) provides a timely review of existing literature integrated with new data from the southern hemisphere. The aim was to characterise the carbonate geochemistry of serpulid worm tubes from around the globe in order to understand the potential effects of changing seawater chemistry on temperate reef ecosystems. For the first time, the authors demonstrated a correlation between the phylogeny and mineral composition of serpulid tubes. Skeletal mineralogy was also found to vary from entirely aragonite to entirely high-Mg calcite to various mixtures of the two. As aragonite and high-Mg calcite are among the most vulnerable minerals to decreasing pH and saturation states (Ries 2011), it was concluded that serpulids are highly vulnerable to changes in ocean chemistry predicted for the near-future. Importantly, however, examples of skeletal mineralogy adjustment in response to changes in seawater chemistry were found, but to the detriment of tube strength and elasticity. In conclusion, the outcomes of Smith et al. (2013) provide important insights into phenotypic and environmental causes of variation in serpulid worm tubes, as well as highlighting the vulnerability of species within the Communicated by U. Sommer.

Heterogeneity in photosynthetic performance between polyp and coenosarc tissue in corals was shown using a new variable fluorescence imaging system (Imaging-PAM) with three species of coral, Acropora nobilis, Cyphastrea serailia and Pocillopora damicornis. In comparison to earlier studies with fibre-optic microprobes for fluorescence analysis, the Imaging-PAM enables greater accuracy by allowing different tissues to be better defined and by providing many more data points within a given time. Spatial variability of photosynthetic performance from the tip to the distal parts was revealed in one species of branching coral, A. nobilis. The effect of bleaching conditions (33°C vs. 27°C) was studied over a period of 8 h. Marked changes in fluorescence parameters were observed for all three species. Although a decline in ΦPSII (effective quantum yield) and Yi (the first effective quantum yield obtained from a rapid light curve) were observed, P. damicornis showed no visual signs of bleaching on the Imaging-PAM after this time. In A. nobilis and C. serailia, visual signs of bleaching over the 8 h period were accompanied by marked changes in F (light-adapted fluorescence yield), NPQ (non-photochemical quenching) and E k (minimum saturating irradiance), as well as ΦPSII and Yi. These changes were most marked over the first 5 h. The most sensitive species was A. nobilis, which after 8 h at 33°C had reached a ΦPSII value of almost zero across its whole surface. Differential bleaching responses between polyps and coenosarc tissue were found in P. damicornis, but not in A. nobilis and C. serailia. NPQ increased with exposure time to 33°C in both the latter species, accompanied by a decreasing E k, suggesting that the xanthophyll cycle is entrained as a mechanism for reducing the effects of the bleaching conditions.

Unfortunately, in the print and online version of article, the title was published incorrectly. The correct title should read as “Evidence of light-induced phenotypic plasticity in zoanthids: editorial comment on the feature article by Ong et al.” Furthermore, the citation Wei et al. (2013) should be replaced with Ong et al. (2013) while the reference Wei ON, Reimer JD, Todd PA (2013) should be replaced with the following Reference section.

The collection of both a checkshot and multi-level walkaway vertical seismic profile (VSP) in the initial exploration well at the Pluto Discovery in the Mississippi Canyon area of the Gulf of Mexico provided a unique opportunity to assess and model the velocity anisotropy present in the area. Pre-well depth estimates based on a 3D pre-stack depth migration were found to give horizon depths that were five percent greater than those actually encountered in the well. A transversely isotropic (TI) velocity model was chosen to image the velocity anisotropy, which, for P-wave propagation, depends essentially on three independent parameters the interval stacking velocity and two unitless parameters, delta and eta. The sediment velocity model for the Pluto Discovery area was divided into five layers conformable with the water bottom surface. Constant delta and eta parameters were determined for each layer. These two parameters combined imply a horizontal P-wave velocity that is eight to sixteen percent faster than the vertical P-wave velocity in the top 14,000 feet of sediments. Travel time estimates from the ray tracing program agreed with the checkshot and walkaway VSP travel times to within one percent, when anisotropy was taken into account, as opposed to six percent for isotropic ray tracing. Based on this information, a 3D poststack depth migration using the TI velocity model showed, versus an isotropic velocity model, correct positioning of events in depth and better resolution of high dipping events. These are outcomes that we would expect from a TI velocity model migration. A checkshot and offset VSP were collected in the second exploration well at the Pluto Discovery. The checkshot data showed a similar vertical velocity structure to that indicated in the first well. The receiver depth range used for the offset VSP included greater depths than in the first well, so the anisotropic nature of the area could be explored deeper. For at least this sedimentary sub-basin, there appears to be little lateral change in the velocity or TI parameters. The TI velocity model at the Pluto Discovery is useful in correcting the depth implied from the pre-stack depth migration and in computing the correct travel paths of the seismic energy. Additionally, a post-stack depth migration using the TI velocity model resulted in sharper images from the sedimentary section. INTRODUCTION It has been known for some time that seismic waves in the earth can travel with different velocities depending on the direction of travel. In most localities this difference in seismic velocity with direction is small. However, in some areas the difference is large enough to cause distorted seismic images and inaccurate depth predictions. The collection of both a checkshot and multi-level walkaway VSP at the Pluto Discovery in the Mississippi Canyon area of the Gulf of Mexico provided an opportunity to assess and model the velocity anisotropy present in the area. Pre-well depth estimates based on a 3D pre-stack depth migration were found to give horizon depths that were five percent greater than those actually encountered in the well. A checkshot could easily correct this problem; however, a broader assessment and interpretation of the velocity anisotropy were desired. A walkaway VSP acquired in the sidetrack well provided the data necessary to measure the vertical versus horizontal velocity in the area. A transversely isotropic velocity model was chosen whose parameters (described below) were taken from Thomsen (1986), and Tsvankin and Thomsen (1994). The Pluto Discovery is in the Mississippi Canyon area of the Gulf of Mexico, approximately 150 miles southeast of New Orleans. The discovery lies in about 2,800 feet of water. The partners in the drilling of the well were British Petroleum, Chevron, and BHP Petroleum. The first well was drilled to 22,389 feet. A checkshot survey was recorded at approximately 250 foot intervals throughout the length of the original well. A sidetrack well was oriented northward from the original hole to investigate additional targets. A walkaway VSP survey was recorded at two different levels in the sidetrack well. An isotropic earth model is easy to imagine. The velocity of the seismic wave at any point within the earth section depends not on its direction, but rather on its spatial location. This holds true even for a vertically gradient earth. For a TI earth, the velocity is considered constant within a horizontal plane, but that velocity is different from the vertical velocity. A TI earth can arise in three main ways. First, a truly anisotropic rock has velocities that differ parallel and perpendicular to bedding planes. A shale could be seen to have this characteristic. Secondly, a series of isotropic rock layers can give rise to an anisotropic earth. 1998 SEG Expanded Abstracts TI velocity parameters at Pluto, GOM Lastly, stress fields within the earth may cause velocities to vary with direction. It is the first two of these mechanisms, anisotropic rocks and/or layered isotropic rocks, that are thought to give rise to the anisotropy found in the Gulf of Mexico. The horizontal velocity is generally greater than the vertical velocity, and theoretically must be if the TI anisotropy arises from layers of isotropic rocks. The parameters necessary for completely characterizing a TI earth include the interval stacking velocity, delta, and eta. The delta parameter is the percentage difference between the squares of the interval stacking velocity and interval checkshot velocity. The delta parameter has been thought of as the vertical anisotropy and corrects the seismic stacking velocity to the checkshot velocity. Eta is a measure of the difference between the squares of the horizontal and stacking velocities. VELOCITY COMPARISONS There are several different relevant velocity functions useful in seismic exploration. Checkshot velocities provide the definitive tie between seismic and well data. Stacking and migration velocities are used in processing seismic data and are normally picked to provide the best seismic image. Thus they are not necessarily tied to the petrophysical parameters of the geologic section. Figure 1 shows that there is a distinct difference between these three velocity functions of checkshot, stacking, and migration for the Pluto area. The stacking velocity function is the average of the velocity functions from the velocity control locations near the well. The migration velocity function is the one used in the prestack depth migration of the seismic data set. Obviously if either the stacking or migration velocity functions were to be used for time-depth conversions, the estimated depths would be too deep. The pre-stack depth migration for Pluto proved to have depth estimates that were 5% too deep at TD.

Phenotypic plasticity refers to the morphological variation of a single genotype across different environments (Kelly et al. 2012). The adaptive advantage of phenotypic plasticity includes the capacity for adjusting to variable environments across multiple habitats and over time as environments experience change. This ability has been documented in a range of benthic marine organisms, including corals (Hoeksema 2012). Like corals and anemones, zoanthids are anthozoans which often harbour symbiotic dinoflagellates (from the genus Symbiodinium). However, zoanthids have received considerably less attention compared to their cnidarian counterparts, with respect to their ecology. It is known that zoanthids exhibit high intraspecific morphological variability (Reimer et al. 2004), but it has been unclear whether this is due to polymorphism, phenotypic plasticity, or a combination of both. The study by Wei et al. (2013) presents the first evidence for phenotypic plasticity in zoanthids. Colonies of Zoanthus sansibaricus and Palythoa tuberculosa all displayed lightinduced changes in morphology. Based on reaction norms, principal components analysis, analysis of variance, and canonical discriminant analysis, the authors demonstrate morphological differences between shading treatments, but also between local populations and a population 9 treatment effect. Polyps of shaded colonies were generally larger and taller than those of unshaded colonies. Population 9 environment interactions show that populations of both species varied in the magnitude and direction of their morphologic responses to shading, suggesting some degree of acclimatization or local adaptation to natal reefs. Importantly, the authors have provided evidence that environmentally mediated changes can contribute to the morphological variation often described in zoanthids (Burnett et al. 1997). These morphologically plastic attributes may enable them to withstand temporal changes in their environment. In addition, given phenotypic plasticity is often associated with a generalist life strategy, these species of zoanthids may survive in spatially variable habitats (van Tienderen 1991). Therefore, this study not only clarifies the effect of illumination in zoanthids but also gives a more general insight on morphology in anthozoans that harbour symbiotic algae.

We describe three men with disseminated, drug-sensitive tuberculosis and advanced human immunodeficiency virus disease (CD4+ lymphocyte count, < 50/mm3) who had flares of tuberculous lymphadenitis with suppuration during the initial weeks of successful chemotherapy. Bactericidal drugs may kindle these transient exacerbations, which involve neutrophils but apparently do not require normal helper T cell function. In patients with AIDS, as in immunocompetent individuals, treatment-related flares of lymphadenitis are usually not an adverse sign, provided that drug resistance and nonadherence have been excluded.

Turning seismic waves, which first travel downward and then upward before (and after) reflection, have been recorded in a 3-D seismic survey conducted over an overhanging salt dome. Careful processing of these turning waves enables the imaging of the underside of the salt dome and of intrusions of salt into vertical faults radiating from the dome. When seismic wave velocity increases with depth, waves that initially travel downward are reflected and may turn so as to travel upward before reflection. A simple geometrical argument suggests that these turning waves are likely to exhibit abnormal moveout in common‐midpoint (CMP) gathers, in that reflection time decreases with increasing source‐receiver offset. This abnormal moveout and the attenuation of turning waves by most migration methods suggest that conventional seismic processing does not properly image turning waves. The most important step in imaging turning waves, assuming that they have been recorded, is the migration process. Simple and inexpensive modifications to the conventional phase‐shift migration method enable turning waves to be imaged for little additional computational cost. The examples provided in this paper suggest that these and other such modifications to conventional processing should be used routinely when imaging salt domes.

Increased ocean temperatures are thought to be triggering mass coral bleaching events around the world. The intracellular symbiotic zooxanthellae (genus Symbiodinium) are expelled from the coral host, which is believed to be a response to photosynthetic damage within these symbionts. Several sites of impact have been proposed, and here we probe the functional heterogeneity of Photosystem II (PSII) in three coral species exposed to bleaching conditions. As length of exposure to bleaching conditions (32°C and 350 μmol photons m-2 s-1) increased, the QA- reoxidation kinetics showed a rise in the proportion of inactive PSII centers (PSIIX), where QB was unable to accept electrons. PSIIX contributed up to 20% of the total PSII centers in Pocillopora damicornis, 35% in Acropora nobilis and 14% in Cyphastrea serailia. Changes in Fv/Fm and amplitude of the J step along fast induction curves were found to be highly dependent upon the proportion of . PSII X centers within the total pool of PSII reaction centers. Determination of PSII antenna size revealed that under control conditions in the three coral species up to 60% of PSII centers were lacking peripheral light-harvesting complexes (PSIIβ). In P. damicornis, the proportion of PSIIβ increased under bleaching conditions and this could be a photoprotective mechanism in response to excess light. The rapid increases in PSIIX and PSIIβ observed in these corals under bleaching conditions indicates these physiological processes are involved in the initial photochemical damage to zooxanthellae. © 2006 American Society for Photobiology.

Information contained in refracted arrivals often can determine shallow, complex structure within the earth. An established way of interpreting refraction arrivals employs graphical construction of wavefronts. Here I extend this graphical method by using numerical downward continuation techniques. For examples of synthetic data and field data, seismic images of irregular interfaces are formed by downward continuing refracted arrivals. For a field‐data example, the image formed from the refraction arrivals is used to correct time‐delay anomalies caused by irregular near‐surface structure. Incorporation of downward continuation into refraction interpretation has several advantages. The method reduces complications due to raypath effects, diffractions, and shadow zones in the refracted arrivals. In addition, this interpretation method reduces the labor and ambiguities associated with identifying first breaks. p‐tau decomposition of the wave field provides a wide‐angle method for downward continuation of refracted arrivals. This method of downward continuation is well suited for refracted arrivals for several reasons. The method allows convenient evaluation of the wave field beneath an irregular recording datum, and it helps overcome spatial aliasing. Also, the calculations can easily be limited to the region of p‐tau space that contains the refracted arrival.

We have studied a patient with hypereosinophilic syndrome (HES) who initially presented with recurrent asthmatic attacks followed by progressive dyspnea. Chronic obstructive lung disease was suspected at first although involvement of cardiac and other organ systems and marked eosinophilia eventually led to the diagnosis. Thereafter a diffuse interstitial pattern gradually developed on the chest radiograph which persisted despite vigorous treatment for cardiac failure. This was due to infiltration and cuffing of the small pulmonary arteries by eosinophils. The bronchi showed changes consistent with asthma. Review of the literature indicates that this type of vascular change is common in HES but involves predominantly organs other than the lung. Similar pulmonary arterial changes have been produced experimentally in the calf by prolonged intravenous infusion of antibiotics, indicating that this may be a hypersensitivity reaction to a blood-borne material entering the pulmonary circulation.

• Five patients with sudden deterioration in respiratory function were studied. In three a history of motor neuron disease was known but in two the first evidence of the disease was severe hypoventilation. No other cause for the respiratory difficulty could be detected in any, and all eventually achieved important partial or even complete independence from mechanical support. Severe hypoventilation can be the initial symptom of motor neuron disease, and not all patients with this complication of the disease have the poor prognosis usually expected.

Fluorometric measurements of maximum quantum yield (Fv/F m) and fast induction curves (FICs) require coral samples to be dark-adapted (DA). Pathways causing dark-reduction of the plastoquinone (PQ) pool are shown here to be active in corals. Early morning sunlight and far-red light successfully increased Fv/Fm and lowered the O and J steps of FICs in corals that were darkened overnight. The thick-tissued massive coral, Cyphastrea serailia, was shown to be more prone to reduction of the PQ pool, with significant reductions in Fv/Fm occurring after 10 min of DA, and elevated J steps occurring within 200 s following a far-red flash. In thinner-tissued branching species, Pocillopora damicornis and Acropora nobilis, elevation of the J step also occurred within 200 s of DA, but a drop in Fv/Fm was only manifested after 30 min. Pre-exposure to far-red light is an effective and simple procedure to ensure determination of the true maximum quantum yield of Photosystem II (PSII) and accurate FICs which require a fully oxidised inter-system electron transport chain and open PSII reaction centres. ©2008 Balaban.

Shallow water coral reefs may experience hypoxia under conditions of calm weather doldrums. Anaerobic responses of endosymbionts (i.e. zooxanthellae) within Pocillopora damicornis coral colonies were tested using both slow and fast chlorophyll a fluorescence induction kinetics. Zooxanthellae were examined in hospite when exposed to control conditions (26°C, 200 μmol photons m-2 s-1, 100% air-saturation, 4 cm s-1 flow) and to 2 treatments of reduced air content (40 and 0%), achieved by controlling the N2:O2 ratio in water circulating at 2 cm s -1. Furthermore, the impact of water flow on photosynthesis was examined at 0% air saturation by turning off the flow entirely (0 cm s -1), thereby mimicking the environmental conditions of calm weather doldrums. Corals exposed to depleted air content (0 % with and without flow) showed a significant decrease (p < 0.001) in effective quantum yield (φPSII) in comparison with controls. Maximum quantum yield was significantly reduced when gas exchange was inhibited (0% without flow), whereas non-photochemical quenching (NPQ) was not affected. Fast polyphasic fluorescence transients of chlorophyll a fluorescence showed a significant increase in minimum dark-adapted fluorescence, F0, when corals were exposed to anaerobic conditions. Furthermore, an increase in the J peak (2 ms) corresponding to the reduction of the primary electron acceptor, QA, was observed in 0% air-saturation with flow. We found that the most sensitive parameters for detecting physiological change associated with hypoxia were φPSII using slow (pulse-amplitude modulation) fluorescence kinetics, as well as an increase in the O peak, φPo(electron transport efficiency before QA), and an elevation of the J peak on a double-normalised transient using fast (Plant Efficiency Analyser) induction kinetics. © Inter-Research 2005.

In this research, methods for the deposition of patterned films and nanostructures were developed from photochemical metal organic deposition (PMOD). Positive lithographic PMOD was demonstrated with films of titanium (IV) di-n-butoxide bis(2-ethylhexanoate) (Ti(OBun)2(eh)2), titanium (IV) diisopropoxide bis(2,4-pentanedionate), and zirconium (IV) di-n-butoxide bis(2,4-pentanedionate). The photochemistry of these complexes in films was studied by FTIR, AES, and XRD. Photo-induced reactivity and polarity changes are believed to affect film solubility in developers. This made it possible to achieve both negative and positive PMOD by simply altering the developers. Electron beam induced metal organic deposition (EMOD) was studied. Feature sizes as small as 12 nm were achieved by negative lithographic EMOD, using Ti(OBun)2(eh)2 and bis(2,2,6,6-tetramethyl-3,5-heptanedionato)(1,5-cyclooctadiene)ruthenium (II), Ru(cod)(tmhd)2. Positive lithographic EMOD was demonstrated for the first time. Two dry lithographic PMOD (and EMOD) methods were developed. In one method, a film formed from tetrakis(trimethylsiloxy)titanium (IV) was used to produce a latent image by masked UV exposure followed by a thermal treatment, which consists of TixSi1-xO2 in the exposed region but TiO2 in the unexposed region. A negative pattern was obtained by etching the latent image with argon plasma. In the other method, a bis(triphenylphosphine) nickel (0) dicarbonyl film was subjected to masked UV exposure followed by a thermal treatment, resulting in a negative pattern. Ru(cod)(tmhd)2 was also tested with this method and feature sizes as small as 20 nm were obtained. The lithographic deposition of films with multiple layers was demonstrated. In this method, a film prepared by sequentially spin coating three solutions of complexes, was subjected to a wet lithographic PMOD process, resulting in a negative pattern with three layers. With this method, bi-layer films with different patterns in each layer, File is read-only.