Search

A single tetrapod tooth has been recovered from the Upper Jurassic Talbragar Fossil Fish Bed of New South Wales, Australia. It is the first evidence of a tetrapod to have been found at this localit...

Despite the evidence that diseases have increased in marine taxa, parasites remain underrepresented in studies of marine ecology. Recently, observations of black-spot syndrome (BSS) in Caribbean fishes, especially ocean surgeonfishes, Acanthurus tractus (Poey, 1860), have been reported, although its cause(s) has remained conjectural. We investigated the etiology of BSS and whether the pathology was functionally and consistently associated with particular infections. By examining the patterns of BSS among reef fishes in Bonaire, we show that observed dermal spots are the encysted stages (metacercariae) of the heterophyid trematode Scaphanocephalus expansus (Creplin, 1842). Metacercariae were detected within ten species of fishes, with loads ranging from 1–315 per fish. These represent the first published accounts of the genus Scaphanocephalus in the Caribbean and are all new host records. Molecular analysis of sequences identified the infection as a heterophyid, while morphological examinations and comparisons with archival specimens confirmed the species identity as S. expansus. Field-based estimates of BSS by scuba divers and subsequent video analysis correlated positively with parasite counts from necropsy. No such correlation was observed between BSS and metacercariae of a second trematode genus, Bucephalus. The consistent link between host burdens of S. expansus and BSS highlights the potential for low-cost and low-impact assessments in fish populations, including the use of images from citizen scientists and public databases. Taken together, these results help establish the foundation for future investigations into the pathology, geographic distribution, life cycle, and ecological consequences of BSS.

Recently, observations of black spot syndrome (BSS) in Caribbean fishes have been linked to infection by a digenean trematode parasite, Scaphanocephalus expansus. Recently, This study examined the distribution of BSS over multiple spatial and temporal scales: at the island scale in Bonaire, Dutch Caribbean, using field surveys of 4885 fish belonging to three species, and across the wider Caribbean through analysis of 2112 images from Google Images searches (1985–2013). The field surveys in Bonaire indicated that the prevalence (% of individuals affected with BSS) and intensity (severity of BSS measured in 3 stages) were highest in Acanthurus tractus (prevalence 61.8%, including 30.1% in stage 3) followed by Sparisoma aurofrenatum (prevalence 48.3%, 24.1% in stage 3) and lowest in Caranx ruber (prevalence 38.5%, 3.3% in stage 3). Prevalence and intensity of BSS decreased significantly with survey depth (e.g., 2 m: prevalence 68.0%, 22.0% in stage 3; 18 m: prevalence 36.2%, 4.0% in stage 3) and were significantly lower in 2012 than in 2017 (prevalence: 59.3% in 2012, 68.7% in 2017; stage 3: 16.3% in 2012, 25.1% in 2017). The Southeast of Bonaire had significantly lower prevalence of BSS (16.4%) than the other four regions and lower intensity (11.7% in stage 3) than all regions but the Southwest. The Google Images searches querying for ocean surgeonfish, A. tractus and A. bahianus, identified pictures from 26 wider Caribbean locations; BSS was detected in 14 locations of which 13 were new, with the first detection dating back to 1985 in Bonaire. The Southern Caribbean had significantly higher prevalence of BSS (78.1%) than other ecoregions (0–34.6%), and Bonaire was identified as a hotspot, highlighting the utility of mining websites for archival imagery to quantify spatial and temporal patterns in disease phenomena. This study demonstrates how visible signs of parasite infection can be used to find differences in parasite prevalence and loads on a reef, island and sea scale.

International audience

Research demonstrates that technological progress in additive manufacturing is mature to ensure high-quality and reliable devices. This emerging interdisciplinary engineering science is becoming commercial and very well documented while opening to new opportunities in several fields. However, it is currently unknown how this additive manufacturing technique might work when applied to frontier technologies such as particle physics detectors as a whole. We hypothesize that a fully automated 3D stack printing of a detector would be ideal to drastically reduce: 1) detector construction time 2) the number of runtime construction errors 3) the probability of mistakes during construction. The initial hypothesis is that 3D printing, applied to instrumentation for physics, will enhance detector performance and capabilities, cutting construction costs and improving standardization over large scale productions. By fully optimizing the entire design and by implementing the construction via additive manufacturing, the expectation is to achieve a standardized RPC detector, mechanically more resistant/resilient and electrically more stable if compared to the state-of-the-art. The successful implementation of this project has the long-term objective to impact not only the physics domain but also the security (cargo imaging and general- purpose scanners) and healthcare (tomography machines) domains, where particle detectors are widely adopted.

Conifer terpenes mediate a number of ecological roles such as deterring herbivory and allelopathic (plant-plant) communication. These terpenes also effect air quality and climate models and are used in chemotaxonomic studies. Herein we report on variation in both intra- and interspecific spruce terpenes using static headspace gas chromatography mass spectrometry (HS-GC-MS) and principal component analysis (PCA) of 'fingerprint' volatile profiles. Samples of blue spruce (Picea pungens), Norway spruce (P. abies), and cedar of Lebanon (Cedrus libani), an outgroup control, were analyzed by HS-GC-MS using both chiral and achiral GC columns. Headspace sampling parameters, temperature and heating time, were optimized to maximize detected terpenes. PCA of terpene 'fingerprint' profiles showed differences by species, by individual trees, but perhaps surprisingly not by environmental conditions. Analysis of blue and Norway spruce over several months show that volatile emissions remained remarkably constant unlike cedar of Lebanon, which showed a much greater variation in volatile profiles. Branches and buds from both spruces were found to release greater amounts of terpenes than samples of needles. The enantiomeric compositions of seven chiral monoterpenes were found to be largely similar between the three conifers with the exception of (-)-α-pinene, which was the dominant enantiomer released by Norway spruce and cedar of Lebanon, while (+)-α-pinene slightly predominated in blue spruce. While not the primary focus of this work, we believe this constitutes the first report on the enantiomeric composition of terpenes in cedar of Lebanon.

In order to determine the depth at which to perform extensive GPS‐tracked surveys, 10 min timed surveys were conducted on SCUBA at depths of 1, 3, 5, 10, 15 and 20 m in non‐mangrove habitats. Timed surveys were performed at 20 haphazardly selected sites around the sheltered coast of Bonaire and Klein Bonaire (Figure S1), during which all S. guacamaia were recorded. Surveys were conducted between 0900 and 1600 hrs to avoid times of day when the parrotfish would be moving to or from night shelter sites. The data were fitted to a generalized linear mixed model (GLMM) using a negative binomial distribution with depth and m!"#$ as covariates and site as a random factor.

This retrospective study examines treatment outcomes associated with atypical antipsychotic medications in areas of 1) treatment response; 2) employment; 3) living arrangements; and 4) hospitalization rates. The study included a random sample of adults with serious mental illness, who participated in treatment for at least 36 months. Study results suggest that the utilization of these medications, despite higher costs, promote cost savings of public dollars through reduced hospitalization and enhanced functioning/outcomes. The study results proved to be very vital to the Virginia State Legislature and key system policy makers and funding authorities, as important actions were taken to enhance consumer access to these important medications and essential services.

Plate tectonic reconstructions of the North Atlantic Margin, west of Britain and Ireland have been generated using computer modelling software. A particular emphasis has been placed on the timing of rift phases within the Rockall Trough as this has significant implications for the distribution of Mesozoic hydrocarbon source rocks. A variety of geophysical and bathymetric data have been integrated to update existing plate boundary definitions, which has improved the resolution of the modelling. Forward and reverse modelling studies were then employed to quantify the amount of rifting in the Rockall Trough. Present-day plate outlines were contracted to discover the amount of intra-plate deformation required for a geometric fit. These results were then compared with the effects of contracting plate outlines by specified amounts using β factors from independent datasets from the Rockall Trough and adjacent areas. The reconstructions suggest that the majority of rifting occurred in the mid to Late Cretaceous and continued into the Eocene. They also indicate the occurrence of at least one episode of pre-Cretaceous rifting corresponding to a β factor of 1.6. The results of this study are corroborated by an independent structural and stratigraphic basin modelling project that examined the crustal evolution of the Rockall Trough. This produced a range of model solutions which, when constrained by data from this study and elsewhere, suggests a best-fit solution which requires a substantially thinned pre-rift crust, best explained by a pre-Cretaceous basin. The implications of the presence of an older rift system are favourable for hydrocarbon exploration in the area. Regionally there are important petroliferous Triassic to Jurassic rift systems and it is likely that an older rift system in the Rockall Trough would be of a similar age with significant potential to be hydrocarbon bearing.

The cost-effectiveness of using the atypical antipsychotic medication clozapine for severe psychosis was examined in a rural public-sector community mental health setting in Virginia. Based on a sample of 20 patients, use of clozapine resulted in estimated cost savings of between $3,000 and $9,000 per patient per year, including the costs of dropouts from treatment. Savings were mainly due to a decline in hospitalization from 47.7+/-59.8 days per patient in the year before clozapine treatment to 4.6+/-11.3 days in the year after. Although this study had methodological limitations, the results suggest that clozapine may be cost-effective in this setting.

This retrospective study examines treatment outcomes associated with atypical antipsychotic medications in areas of 1) treatment response; 2) employment; 3) living arrangements; and 4) hospitalization rates. The study included a random sample of adults with serious mental illness, who participated in treatment for at least 36 months. Study results suggest that the utilization of these medications, despite higher costs, promote cost savings of public dollars through reduced hospitalization and enhanced functioning/outcomes. The study results proved to be very vital to the Virginia State Legislature and key system policy makers and funding authorities, as important actions were taken to enhance consumer access to these important medications and essential services.

To provide medical and pharmaceutical practitioners with information on the effectiveness, safety and risks associated with barbiturate-containing analgesic (BCA) agents and an approach to management of withdrawal from BCAs.The benefits of using BCAs in the treatment of pain (compared with using non-BCAs) were weighed against potential risks. The procedures for discontinuation of BCAs in patients with pain were considered, and evidence showing that BCAs constitute a public health risk was reviewed. The evidence serving as the basis for the clinical guidelines was compiled from a number of sources, including key papers in the field, published and unpublished papers, and reports by Addiction Research Foundation researchers, a MEDLINE search from 1967 to November 1996, and communication with Canadian manufacturers of BCAs.There is no evidence that there is a clinically important enhancement of analgesic efficacy of BCAs due to the barbiturate constituent. No epidemiological studies on the relative frequency of abuse and dependence, or studies that have analyzed combination product use from a public health and social benefit to risk perspective, have been published to clarify the issues about the nature, extent and seriousness of these problems.No evidence exists to show a clinically important enhancement of analgesic efficacy of BCAs due to the barbiturate constituents. Because BCAs do not have a therapeutic advantage, there is no clinical reason to choose such a combination product when a simpler and often less expensive analgesic formulation (eg, acetaminophen, acetylsalicylic acid, nonsteroidal anti-inflammatory drug or narcotic) or a more specific anti-migraine drug (eg, dihydroergotamine or sumatriptan) is available. BCAs should be avoided in elderly people and should not be used in children. Extrapolation from published reports on abuse and withdrawal syndrome with these drugs suggests that BCAs have the potential to produce drug dependence and addictive behaviour, especially with regular use. In BCA overdose, the barbiturate component is only one of the clinically significant contributors to any morbidity, but its presence can complicate the management of additive or synergistic toxicities. Therefore, there is no reason to choose a combination product when a simpler product may be a safer alternative by minimizing the potential for addiction and the occurrence of additive side effects or toxicities. It is further recommended that prescribers re-evaluate treatment for patients using BCAs. Recommendations for withdrawal are provided, based on estimated consumption.

Several phosphate esters in which calixarenes act as either uni- or bi-dentate ligands towards PV have been investigated as solvent-extraction agents for the rare-earth metals (La to Lu, excluding Pm, plus Y). Extraction of picrate salts into dichloromethane, ethyl acetate and tributyl phosphate–hexane (1 : 1) is considerably enhanced by some of these esters but in no case is any marked selectivity exhibited, although some features of the observed extraction patterns suggest ways in which the molecular design of such extractants may be improved. Crystal structure determinations on two phosphate esters in which the calixarene unit is bidentate indicate that the relatively poor metal-ion binding abilities of these ligands may be a consequence of a preferred orientation of the phosphoryl donor groups in which they diverge from the macrocyclic ring. A crystal structure determination on the 2 : 1 complex of tetrakis-O-(diethoxyphosphoryl)-p-tert-butylcalix[4]arene and lanthanum picrate (2,4,6-trinitrophenolate) shows that a convergent array of phosphoryl donor groups can form in such cases where the functional groups are flexible. This does not, however, appear to lead to a particular enhancement of stability, as the complex readily dissociates into a 1 : 1 species in solution.

An instrument for the rapid routine counting of tritium is described. It utilizes a liquid scintillator with coincidence circuitry, and incorporates a new fixed-cell design. An introductory analysis of the geometry of the system is made. The optimum counting efficiency of the counter for tritium in 25 ml of toluene-based scintillator is 25% with a background of 180 c.p.m. The use of the counter with tritiated water samples and with 14C/3H mixtures is described.

n/a

A Machine has been built in the Hammersmith Hospital Physics Department to relieve the tedium of routine isotope scanning by hand. An automatic scanner was needed which had to be cheap, within the capabilities of our limited work-shop, and using as much standard equipment as possible. It was felt that it would be desirable for the machine to give not only the pictorial distribution of radioactivity localised in part of the body, but also the same information as a hand-operated scan, i.e. the count-rate at any point and lines of equal count-rate or isocount lines. The principle of the so-called “scintiscanner” is familiar (e.g. Bolliger and Poretti, 1956); a pictorial distribution is built up from a series of black marks on paper—a single mark being made for a selected total number of pulses received. At higher count-rates the dots are closer together than at lower count-rates and the eye is capable of picking out the areas of higher count-rate as areas of greater density of dots (Fig. 8). In order to obta...

n/a