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The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Radiocarbon (14C or carbon-14, half-life 5730 yr) is a key radionuclide in the assessment of the safety of a geological disposal facility (GDF) for radioactive waste. In particular, the radiological impact of gaseous carbon-14 bearing species has been recognized as a potential issue. Irradiated steels are one of the main sources of carbon-14 in the United Kingdom’s radioactive waste inventory. However, there is considerable uncertainty about the chemical form(s) in which the carbon-14 will be released. The objective of the work was to measure the rate and speciation of carbon-14 release from irradiated 316L(N) stainless steel on leaching under high-pH anoxic conditions, representative of a cement-based near field for low-heat generating wastes. Periodic measurements of carbon-14 releases to both the gas phase and to solution were made in duplicate experiments over a period of up to 417 days. An initial fast release of carbon-14 from the surface of the steel is observed during the first week of leaching, followed by a drop in the rate of release at longer times. Carbon-14 is released primarily to the solution phase with differing fractions released to the gas phase in the two experiments: about 1% of the total release in one and 6% in the other. The predominant dissolved carbon-14 releases are in inorganic form (as 14C-carbonate) but also include organic species. The predominant gas-phase species are hydrocarbons with a smaller fraction of 14CO (which may include some volatile oxygen-containing carbon-species). The experiments are continuing, with final sampling and termination planned after leaching for a total of two years.
Infants with prenatally diagnosed CHD are at high risk for adverse outcomes owing to multiple physiologic and psychosocial factors. Lack of immediate physical postnatal contact because of rapid initiation of medical therapy impairs maternal–infant bonding. On the basis of expected physiology, maternal–infant bonding may be safe for select cardiac diagnoses.
This is a single-centre study to assess safety of maternal–infant bonding in prenatal CHD.
In total, 157 fetuses with prenatally diagnosed CHD were reviewed. On the basis of cardiac diagnosis, 91 fetuses (58%) were prenatally approved for bonding and successfully bonded, 38 fetuses (24%) were prenatally approved but deemed not suitable for bonding at delivery, and 28 (18%) were not prenatally approved to bond. There were no complications attributable to bonding. Those who successfully bonded were larger in weight (3.26 versus 2.6 kg, p<0.001) and at later gestation (39 versus 38 weeks, p<0.001). Those unsuccessful at bonding were more likely to have been delivered via Caesarean section (74 versus 49%, p=0.011) and have additional non-cardiac diagnoses (53 versus 29%, p=0.014). There was no significant difference regarding the need for cardiac intervention before hospital discharge. Infants who bonded had shorter hospital (7 versus 26 days, p=0.02) and ICU lengths of stay (5 versus 23 days, p=0.002) and higher survival (98 versus 76%, p<0.001).
Fetal echocardiography combined with a structured bonding programme can permit mothers and infants with select types of CHD to successfully bond before ICU admission and intervention.
Although dementia has been described in ancient texts over many centuries (e.g., “Be kind to your father, even if his mind fail him.” – Old Testament: Sirach 3:12), our knowledge of its underlying causes is little more than a century old. Alzheimer published his now famous case study only 110 years ago, and our modern understanding of the disease that bears his name, and its neuropsychological consequences, really only began to accelerate in the 1980s. Since then we have witnessed an explosion of basic and translational research into the causes, characterizations, and possible treatments for Alzheimer’s disease (AD) and other dementias. We review this lineage of work beginning with Alzheimer’s own writings and drawings, then jump to the modern era beginning in the 1970s and early 1980s and provide a sampling of neuropsychological and other contextual work from each ensuing decade. During the 1980s our field began its foundational studies of profiling the neuropsychological deficits associated with AD and its differentiation from other dementias (e.g., cortical vs. subcortical dementias). The 1990s continued these efforts and began to identify the specific cognitive mechanisms affected by various neuropathologic substrates. The 2000s ushered in a focus on the study of prodromal stages of neurodegenerative disease before the full-blown dementia syndrome (i.e., mild cognitive impairment). The current decade has seen the rise of imaging and other biomarkers to characterize preclinical disease before the development of significant cognitive decline. Finally, we suggest future directions and predictions for dementia-related research and potential therapeutic interventions. (JINS, 2017, 23, 818–831)
We summarize the methods of a new “hybrid” computer code for stellar dynamics. All particles in the inner spatial region are followed exactly via a direct N-body code and all particles in the outer spatial region are treated statistically via a distribution function and Fokker-Planck type methods. An intermediate region, with features of both, allows exchange of particles and energy between the outer and inner regions. We apply our code to the period just before core collapse and just after and summarize the results.
A number of laser facilities coming online all over the world promise the capability of high-power laser experiments with shot repetition rates between 1 and 10 Hz. Target availability and technical issues related to the interaction environment could become a bottleneck for the exploitation of such facilities. In this paper, we report on target needs for three different classes of experiments: dynamic compression physics, electron transport and isochoric heating, and laser-driven particle and radiation sources. We also review some of the most challenging issues in target fabrication and high repetition rate operation. Finally, we discuss current target supply strategies and future perspectives to establish a sustainable target provision infrastructure for advanced laser facilities.
Because individuals develop dementia as a manifestation of neurodegenerative or neurovascular disorder, there is a need to develop reliable approaches to their identification. We are undertaking an observational study (Ontario Neurodegenerative Disease Research Initiative [ONDRI]) that includes genomics, neuroimaging, and assessments of cognition as well as language, speech, gait, retinal imaging, and eye tracking. Disorders studied include Alzheimer’s disease, amyotrophic lateral sclerosis, frontotemporal dementia, Parkinson’s disease, and vascular cognitive impairment. Data from ONDRI will be collected into the Brain-CODE database to facilitate correlative analysis. ONDRI will provide a repertoire of endophenotyped individuals that will be a unique, publicly available resource.
New paediatric cardiology trainees are required to rapidly assimilate knowledge and gain clinical skills to which they have limited or no exposure during residency. The Pediatric Cardiology Fellowship Boot Camp (PCBC) at Boston Children’s Hospital was designed to provide incoming fellows with an intensive exposure to congenital cardiac pathology and a broad overview of major areas of paediatric cardiology practice.
The PCBC curriculum was designed by core faculty in cardiac pathology, echocardiography, electrophysiology, interventional cardiology, exercise physiology, and cardiac intensive care. Individual faculty contributed learning objectives, which were refined by fellowship directors and used to build a programme of didactics, hands-on/simulation-based activities, and self-guided learning opportunities.
A total of 16 incoming fellows participated in the 4-week boot camp, with no concurrent clinical responsibilities, over 2 years. On the basis of pre- and post-PCBC surveys, 80% of trainees strongly agreed that they felt more prepared for clinical responsibilities, and a similar percentage felt that PCBC should be offered to future incoming fellows. Fellows showed significant increase in their confidence in all specific knowledge and skills related to the learning objectives. Fellows rated hands-on learning experiences and simulation-based exercises most highly.
We describe a novel 4-week-long boot camp designed to expose incoming paediatric cardiology fellows to the broad spectrum of knowledge and skills required for the practice of paediatric cardiology. The experience increased trainee confidence and sense of preparedness to begin fellowship-related responsibilities. Given that highly interactive activities were rated most highly, boot camps in paediatric cardiology should strongly emphasise these elements.
We analysed the supportive social networks associated with the conservation of six threatened Australian bird taxa, in one of the first network analyses of threatened species conservation programmes. Each example showed contrasting vulnerabilities. The Alligator Rivers yellow chat Epthianura crocea tunneyi had the smallest social network and no real action was supported. For the Capricorn yellow chat Epthianura crocea macgregori the network was centred on one knowledgeable and committed actor. The orange-bellied parrot Neophema chrysogaster had a strongly connected recovery team but gaps in the overall network could limit communication. The recovery teams for the swift parrot Lathamus discolor and Baudin's black-cockatoo Calyptorhynchus baudinii had strong links among most stakeholders but had weak ties to the timber industry and orchardists, respectively, limiting their capacity to manage threatening processes. Carnaby's black cockatoo Calyptorhynchus latirostris seemed to have the most effective social network of any of the taxa studied but may be vulnerable to skill shortages. In each case the network analysis pointed to gaps that could be filled to enhance the conservation effort, and highlighted the importance of recovery teams. The research suggests that formal network analysis could assist in the design of more effective support mechanisms for the conservation of threatened species.
The Millimetre Astronomy Legacy Team 90 GHz survey aims to characterise the physical and chemical evolution of high-mass clumps. Recently completed, it mapped 90 GHz line emission towards 3 246 high-mass clumps identified from the ATLASGAL 870 μm Galactic plane survey. By utilising the broad frequency coverage of the Mopra telescope’s spectrometer, maps in 16 different emission lines were simultaneously obtained. Here, we describe the first catalogue of the detected line emission, generated by Gaussian profile fitting to spectra extracted towards each clumps’ 870 μm dust continuum peak. Synthetic spectra show that the catalogue has a completeness of > 95%, a probability of a false-positive detection of < 0.3%, and a relative uncertainty in the measured quantities of < 20% over the range of detection criteria. The detection rates are highest for the (1–0) transitions of HCO+, HNC, N2H+, and HCN (~77–89%). Almost all clumps (~95%) are detected in at least one of the molecular transitions, just over half of the clumps (~53%) are detected in four or more of the transitions, while only one clump is detected in 13 transitions. We find several striking trends in the ensemble of properties for the different molecular transitions when plotted as a function of the clumps’ evolutionary state as estimated from Spitzer mid-IR images, including (1) HNC is relatively brighter in colder, less evolved clumps than those that show active star formation, (2) N2H+ is relatively brighter in the earlier stages, (3) that the observed optical depth decreases as the clumps evolve, and (4) the optically thickest HCO+ emission shows a ‘blue-red asymmetry’ indicating overall collapse that monotonically decreases as the clumps evolve. This catalogue represents the largest compiled database of line emission towards high-mass clumps and is a valuable data set for detailed studies of these objects.
1) To evaluate whether transient ischemic attack (TIA) management in emergency departments (EDs) of the Nova Scotia Capital District Health Authority followed Canadian Best Practice Recommendations, and 2) to assess the impact of being followed up in a dedicated outpatient neurovascular clinic.
Retrospective chart review of all patients discharged from EDs in our district from January 1, 2011 to December 31, 2012 with a diagnosis of TIA. Cox proportional hazards models, Kaplan-Meier survival curve, and propensity matched analyses were used to evaluate 90-day mortality and readmission.
Of the 686 patients seen in the ED for TIA, 88.3% received computed tomography (CT) scanning, 86.3% received an electrocardiogram (ECG), 35% received vascular imaging within 24 hours of triage, 36% were seen in a neurovascular clinic, and 4.2% experienced stroke, myocardial infarction, or vascular death within 90 days. Rates of antithrombotic use were increased in patients seen in a neurovascular clinic compared to those who were not (94% v. 86.3%, p<0.0001). After adjustment for age, sex, vascular disease risk factors, and stroke symptoms, the risk of readmission for stroke, myocardial infarction, or vascular death was lower for those seen in a neurovascular clinic compared to those who were not (adjusted hazard ratio 0.28; 95% confidence interval 0.08–0.99, p=0.048).
The majority of patients in our study were treated with antithrombotic agents in the ED and investigated with CT and ECG within 24 hours; however, vascular imaging and neurovascular clinic follow-up were underutilized. For those with neurovascular clinic follow-up, there was an association with reduced risk of subsequent stroke, myocardial infarction, or vascular death.
Polychrome slipped and decorated pottery from Corinth, Greece, developed over two centuries from monochrome, dark brown slips and washes on a calcareous yellow clay body to a wide range of decorative techniques. Once significant experimentation with color variability began, five colors, each with various levels of gloss, were produced. Some slip colors involve multiple-step processing to control glass content and degree of sintering; the control of particle size to produce variable roughness and a matte or semi-matt or glossy appearance. Considerable evidence supports nearly continuous development and engineering of the ceramic slips, although no data support the improvement in composition or processing of the ceramic bodies. For instance, significant macro-porosity consistently is present in the bodies. We present the results of study of 27 sherds with 59 examples of Corinthian polychrome paint layers, measuring 5 to 35 microns in thickness, that were collected by Marie Farnsworth in the late 1950s and 1960s from Greek archaeological sites. Black, red, white, wine red (or purple) and overlying, matte banded slips and paints were studied by optical microscopy, petrographic and scanning-electron microscopy with semi-quantative energy dispersive x-ray analysis, as well as wavelength-dispersive electron microprobe (EPMA) elemental mapping and analysis.
Discovery of ultra-compact dwarfs (UCDs) in the past 15 years blurs the once thought clear division between classic globular clusters (GCs) and early-type galaxies. The intermediate nature of UCDs, which are larger and more massive than typical GCs but more compact than typical dwarf galaxies, has triggered hot debate on whether UCDs should be considered galactic in origin or merely the most extreme GCs. Previous studies of various scaling relations, stellar populations and internal dynamics did not give an unambiguous answer to the primary origin of UCDs. In this contribution, we present the first ever detailed study of global dynamics of 97 UCDs (rh ≳ 10 pc) associated with the central cD galaxy of the Virgo cluster, M87. We found that UCDs follow a different radial number density profile and different rotational properties from GCs. The orbital anisotropies of UCDs are tangentially-biased within ~ 40 kpc of M87 and become radially-biased with radius further out. In contrast, the blue GCs, which have similar median colors to our sample of UCDs, become more tangentially-biased at larger radii beyond ~ 40 kpc. Our analysis suggests that most UCDs in M87 are not consistent with being merely the most luminous and extended examples of otherwise normal GCs. The radially-biased orbital structure of UCDs at large radii is in general agreement with the scenario that most UCDs originated from the tidally threshed dwarf galaxies.