Coronary Computed Tomographic Angiography at 80 kVp and Knowledge-Based Iterative Model Reconstruction Is Non-Inferior to that at 100 kVp with Iterative Reconstruction

The aims of this study were to compare the image noise and quality of coronary computed tomographic angiography (CCTA) at 80 kVp with knowledge-based iterative model reconstruction (IMR) to those of CCTA at 100 kVp with hybrid iterative reconstruction (IR), and to evaluate the feasibility of a low-dose radiation protocol with IMR. Thirty subjects who underwent prospective electrocardiogram-gating CCTA at 80 kVp, 150 mAs, and IMR (Group A), and 30 subjects with 100 kVp, 150 mAs, and hybrid IR (Group B) were retrospectively enrolled after sample-size calculation. A BMI of less than 25 kg/m2 was required for inclusion. The attenuation value and image noise of CCTA were measured and the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated at the proximal right coronary artery and left main coronary artery. The image noise was analyzed using a non-inferiority test. The CCTA images were qualitatively evaluated using a four-point scale. The radiation dose was significantly lower in Group A than Group B (0.69 ± 0.08 mSv vs. 1.39 ± 0.15 mSv, p < 0.001). The attenuation values were higher in Group A than Group B (p < 0.001). The SNR and CNR in Group A were higher than those of Group B. The image noise of Group A was non-inferior to that of Group B. Qualitative image quality of Group A was better than that of Group B (3.6 vs. 3.4, p = 0.017). CCTA at 80 kVp with IMR could reduce the radiation dose by about 50%, with non-inferior image noise and image quality than those of CCTA at 100 kVp with hybrid IR

Coronary dominance and prognosis in patients undergoing coronary computed tomographic angiography: results from the CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry

Aims Coronary computed tomographic angiography (CCTA) has become an important tool for non-invasive diagnosis of coronary artery disease (CAD). Coronary dominance can be assessed by CCTA; however, the predictive value of coronary dominance is controversially discussed. The aim of this study was to evaluate the prevalence and prognosis of coronary dominance in a large prospective, international multicentre cohort of patients undergoing CCTA. Methods and results The study population consisted of 6382 patients with or without CAD (47% females, 53% males, mean age 56.9 ± 12.3 years) who underwent CCTA and were followed over a period of 60 months. Right or left coronary dominance was determined. Right dominance was present in 91% (n = 5817) and left in 9% (n = 565) of the study population. At the end of follow-up, outcome in patients with obstructive CAD (>50% luminal stenosis) and right dominance was similar compared with patients with left dominance [hazard ratio (HR) 0.46, 95% CI 0.16-1.32, P = 0.15]. Furthermore, no differences were observed for the type of coronary dominance in patients with non-obstructive CAD (HR 0.95, 95% CI 0.41-2.21, P = 0.8962) or normal coronary arteries (HR 1.04, 95% CI 0.68-1.59, P = 0.9). Subgroup analysis in patients with left main disease revealed an elevated hazard of the combined endpoint for left dominance (HR 6.45, 95% CI 1.66-25.0, P = 0.007), but not for right dominance. Conclusion In our study population, survival after 5 years of follow-up did not differ significantly between patients with left or right coronary dominance. Thus, assessment of coronary vessel dominance by CCTA may not enhance risk stratification in patients with normal coronary arteries or obstructive CAD, but may add prognostic information for specific subpopulation

Early carboniferous brachiopod faunas from the Baoshan block, west Yunnan, southwest China

38 brachiopod species in 27 genera and subgenera are described from the Yudong Formation in the Shidian-Baoshan area, west Yunnan, southwest China. New taxa include two new subgenera: Unispirifer (Septimispirifer) and Brachythyrina (Longathyrina), and seven new species: Eomarginifera yunnanensis, Marginatia cylindrica, Unispirifer (Unispirifer) xiangshanensis, Unispirifer (Septimispirifer) wafangjieensis, Brachythyrina (Brachythyrina) transversa, Brachythyrina (Longathyrina) baoshanensis, and Girtyella wafangjieensis. Based on the described material and constraints from associated coral and conodont faunas, the age of the brachiopod fauna from the Yudon Formation is considered late Tournaisian (Early Carboniferous), with a possibility extending into earlyViseacutean.<br /

Carboniferous and Permian Rugosochonetidae (Brachiopoda) from West Spitsbergen

The rugosochonetid brachiopod species Lissochonetes geinitzianus from the Kazimovian of the Nordenskioldbreen Formation, and Dyoros (Dyoros) mucronata sp. nov., Dyoros (Dyoros) spitzbergianus and Lissochonetes superba from the Artinskian to latest Permian Kapp Starostin Formation in West Spitsbergen are described and figured. Dyoros is generally restricted to the Boreal Realm, whereas Lissochonetes is mostly distributed in the Boreal Realm, but occasionally present in the Palaeoequatorial and Gondwanan Realms<br /

Colonization and community development of fish assemblages associated with estuarine artificial reefs

Despite the long history of the development of artificial structures in NSW estuaries there are no studies that provide any comprehensive scientific evaluation of post-deployment goals. We assessed the effectiveness of estuarine artificial reefs as a fisheries enhancement initiative; described the diversity and abundance of species associated with them, and detailed the patterns of colonization and community development associated with an artificial reef deployment in Lake Macquarie, a large coastal barrier lagoon on the southeast coast of Australia. Six artificial reefs (one artificial reef group), constructed from artificial reef units (Reef Balls®), were deployed in December 2005 and sampled six times per season over two years using baited remote underwater video (BRUV). Colonization of the artificial reef group was relatively rapid with the majority of species identified over the two-year study period observed within the first year post-deployment. Overall, 27 species from 17 families were identified. Key colonising species included Pelates sexlineatus (Terapontidae), Acanthopagrus australis (Sparidae), Pagrus auratus (Sparidae) and Rhabdosargus sarba (Sparidae). Species richness showed evidence of potential seasonal fluctuations, being higher in warm water months (Summer/Autumn), and lower in the colder water months (Winter/Spring), while species diversity increased significantly with reef age. Fish assemblage composition remained relatively stable after the first year of sampling, with few discernible patterns in assemblage structure evident after the first year. Distinct separation in reef age groupings was evident during the second year of sampling; a pattern primarily driven by a decrease in abundance of P. sexlineatus, a result of the isolated nature of the artificial reefs and the interrelated effects of density dependence and predation.A despeito da longa história do desenvolvimento de estruturas artificiais nos estuários de NSW, não existem estudos que apresentem uma avaliação global sobre os efeitos obtidos com o estabelecimento dessas estruturas. No presente trabalho abordamos a efetividade dos recifes artificiais estuarinos como iniciativa para aumento da pesca; descrevemos a diversidade e abundância das espécies a eles associadas; descrevemos os padrões de colonização e o desenvolvimento das comunidades associadas a um recife artificial colocado no Lago Macquaire, extensa lagoa de barreira situada na costa sudeste da Australia. Seis recifes artificiais (formando um único grupo), construídos a partir de unidades artificiais (Reef Balls®), foram lançados em Dezembro de 2005 e amostrados seis vezes a cada estação do ano, durante dois anos, utilizando video subaquático remoto (BRUV). A colonizaç��o dentro do grupo de recifes ocorreu de maneira relativamente rápida, sendo que a maioria das espécies identificadas nos dois anos de estudo foi observada durante o primeiro ano de amostragem. Um total de 27 espécies pertencentes a 17 famílias foram identificadas. As espécies chave do processo de colonização foram Pelates sexlineatus (Teraponidae), Acanthopagrus australis (Sparidae), Pagrus auratus (Sparidae) and Rhabdosargus sarba (Sparidea). A riqueza de espécies mostrou evidência de sazonalidade, enquanto a diversidade aumentou significativamente com o aumento da idade do recife. A composição da assembléia de peixes permaneceu relativamente estável após o primeiro ano de amostragem, com poucos padrões identificáveis relativos à estrutura. Durante o segundo ano tornou-se evidente a formação de grupos por idade, padrão primariamente ocasionado pelo decréscimo na abundância de P. sexlineatus; por sua vez este decréscimo mostrou ser resultado da natureza isolada do recife artificial e dos efeitos interdependentes de abundância e predação

Attenuation correction maps for SPECT myocardial perfusion imaging from contrast-enhanced coronary CT angiography: Gemstone spectral imaging with single-source dual energy and material decomposition

The aim of this study was to explore the feasibility of attenuation correction (AC) of myocardial perfusion imaging (MPI) with a virtual unenhanced cardiac CT scan synthesized from contrast-enhanced single-source dual-energy coronary CT angiography. METHODS: Segmental myocardial percentage uptake values obtained with AC were analyzed by use of correlation analysis and Bland-Altman limits of agreement (20-segment model), and clinical agreement was evaluated in 30 patients. RESULTS: The 2 methods showed an excellent correlation for segmental myocardial percentage uptake at stress (r = 0.93; P < 0.001; low dose) and at rest (r = 0.90; P < 0.001; high dose) with narrow Bland-Altman limits of agreement (-6.8% to 7.8% and -7.8% to 7.4%, respectively). The levels of clinical agreement of SPECT MPI corrected with standard versus virtual unenhanced CT AC were 99% per coronary territory and 97% per patient. CONCLUSION: Our results suggest that AC of SPECT MPI with a virtual unenhanced CT scan synthesized from contrast-enhanced coronary CT angiography is feasible and reliable

MR-based attenuation correction for cardiac FDG PET on a hybrid PET/MRI scanner: comparison with standard CT attenuation correction

PURPOSE: The aim of this study was to evaluate the feasibility of attenuation correction (AC) for cardiac (18)F-labelled fluorodeoxyglucose (FDG) positron emission tomography (PET) using MR-based attenuation maps. METHODS: We included 23 patients with no known cardiac history undergoing whole-body FDG PET/CT imaging for oncological indications on a PET/CT scanner using time-of-flight (TOF) and subsequent whole-body PET/MR imaging on an investigational hybrid PET/MRI scanner. Data sets from PET/MRI (with and without TOF) were reconstructed using MR AC and semi-quantitative segmental (20-segment model) myocardial tracer uptake (per cent of maximum) and compared to PET/CT which was reconstructed using CT AC and served as standard of reference. RESULTS: Excellent correlations were found for regional uptake values between PET/CT and PET/MRI with TOF (n = 460 segments in 23 patients; r = 0.913; p < 0.0001) with narrow Bland-Altman limits of agreement (-8.5 to +12.6 %). Correlation coefficients were slightly lower between PET/CT and PET/MRI without TOF (n = 460 segments in 23 patients; r = 0.851; p < 0.0001) with broader Bland-Altman limits of agreement (-12.5 to +15.0 %). PET/MRI with and without TOF showed minimal underestimation of tracer uptake (-2.08 and -1.29 %, respectively), compared to PET/CT. CONCLUSION: Relative myocardial FDG uptake obtained from MR-based attenuation corrected FDG PET is highly comparable to standard CT-based attenuation corrected FDG PET, suggesting interchangeability of both AC techniques

Severe deprivation in early childhood leads to permanent growth stunting: Longitudinal analysis of height trajectories from childhood-to-adulthood

Background Childhood institutional deprivation is associated with growth stunting in childhood but long-term effects in adulthood remain uncertain. Objective To examine the impact of global institutional deprivation experienced in early childhood on subsequent growth with a special focus on final adult height and puberty timing. Participants &amp; setting The study was originally set in the UK, though some adoptive families lived abroad by the time of the adult follow up. 165 individuals adopted by UK families before 43 months of age from Romanian orphanages after the fall of the Ceaușescu regime in the early 1990's were compared to 51 non-deprived UK adoptees, adopted before the age of 6 months. Methods The English and Romanian Adoptees (ERA) study is a 20-year longitudinal natural experiment on the effects of institutional deprivation on development. Key growth milestones were extracted from growth curve modelling of height data collected at ages 4, 6, 11, 15 and 23 years using a Bayesian approach to fit the JPA2 model. Results Deprivation effects on height were present at the take-off point of accelerating adolescent growth and persisted into adulthood – the largest effects being for individuals who experienced over six months of deprivation. Deprivation was associated with earlier take-off and achievement of peak height velocity of adolescent growth acceleration – an effect driven largely by females' data and correlated with parent ratings of pubertal development. Conclusions Early deprivation appears to reset tempo of growth early in development leading to permanent growth stunting in adulthood and accelerated onset of puberty, specifically in females