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In recent years, the discovery of massive quasars at
has provided a striking challenge to our understanding of the origin and growth of supermassive black holes in the early Universe. Mounting observational and theoretical evidence indicates the viability of massive seeds, formed by the collapse of supermassive stars, as a progenitor model for such early, massive accreting black holes. Although considerable progress has been made in our theoretical understanding, many questions remain regarding how (and how often) such objects may form, how they live and die, and how next generation observatories may yield new insight into the origin of these primordial titans. This review focusses on our present understanding of this remarkable formation scenario, based on the discussions held at the Monash Prato Centre from November 20 to 24, 2017, during the workshop ‘Titans of the Early Universe: The Origin of the First Supermassive Black Holes’.
The use of three-dimensional printing has been rapidly expanding over the last several decades. Virtual surgical three-dimensional simulation and planning has been shown to increase efficiency and accuracy in various clinical scenarios.
To report the feasibility of three-dimensional printing in paediatric laryngotracheal stenosis and discuss potential applications of three-dimensional printed models in airway surgery.
Retrospective case series in a tertiary care aerodigestive centre.
Three-dimensional printing was undertaken in two cases of paediatric laryngotracheal stenosis. One patient with grade 4 subglottic stenosis with posterior glottic involvement underwent an extended partial cricotracheal reconstruction. Another patient with grade 4 tracheal stenosis underwent tracheal resection and end-to-end anastomosis. Models of both tracheas were printed using PolyJet technology from a Stratasys Connex2 printer.
It is feasible to demonstrate stenosis in three-dimensional printed models, allowing for patient-specific pre-operative surgical simulation. The models serve as an educational tool for patients’ understanding of the surgery, and for teaching residents and fellows.
Keel bone damage (KBD) in laying hens is an important welfare problem in both conventional and organic egg production systems. We aimed to identify possible risk factors for KBD in organic hens by analysing cross-sectional data of 107 flocks assessed in eight European countries. Due to partly missing data, the final multiple regression model was based on data from 50 flocks. Keel bone damage included fractures and/or deviations, and was recorded, alongside with other animal based measures, by palpation and visual inspection of at least 50 randomly collected hens per flock between 52 and 73 weeks of age. Management and housing data were obtained by interviews, inspection and by feed analysis. Keel bone damage flock prevalences ranged from 3% to 88%. Compiled on the basis of literature and practical experience, 26 potential associative factors of KBD went into an univariable selection by Spearman correlation analysis or Mann–Whitney U test (with P<0.1 level). The resulting nine factors were presented to stepwise forward linear regression modelling. Aviary v. floor systems, absence of natural daylight in the hen house, a higher proportion of underweight birds, as well as a higher laying performance were found to be significantly associated with a higher percentage of hens with KBD. The final model explained 32% of the variation in KBD between farms. The moderate explanatory value of the model underlines the multifactorial nature of KBD. Based on the results increased attention should be paid to an adequate housing design and lighting that allows the birds easy orientation and safe manoeuvring in the system. Furthermore, feeding management should aim at sufficient bird live weights that fulfil breeder weight standards. In order to achieve a better understanding of the relationships between laying performance, feed management and KBD further investigations are needed.
Introduction: Foreign patients often do not receive appropriate treatment in the emergency room as compared to locals. This is due to various causes such as language, insurance, and cultural differences. The purpose of this study was to investigate whether there is a wide range of health inequalities among foreigners who visited the emergency room with injury and to find out what causes it. Methods: We analyzed clinical data from the National Emergency Department Information System(NEDIS) database, which visited the emergency room from January 1, 2013 to December 31, 2015, in all age groups. Foreigners are classified based on the personal information described in the NEDIS. We analyzed the number of injuries, serious cases(death, operation, ICU admission), length of stay in ER, and transfer ratio. Results: A total of 4,464,603 cases of injured patients were included, of whom 67,683 were foreign patients. The incidence rate per 100,000 people per year was 2960.5 from locals and 1659.8 from foreigners. Serious outcomes were higher for foreigners than for locals(31.0% versus 23.2%, p<0.001). There was a further difference in the rural region. Length of stay was longer for foreigners(72 versus 69 minutes, median, p<0.001). The transfer rate was also higher for foreigners(1.9% versus 1.6%, p<0.001). Daegu had the highest ratio of foreigners’ injury compared to locals(ratio=0.998). Jeonnam(0.073) was the highest serious outcome rate in Korea, and Jeonbuk(0.070) was the second. The area with the longest length of stay in the Emergency department was the median 139 minutes for locals and 153 minutes for foreigners in Daegu. The more patients per day, the shorter the time spent in the emergency rooms(Spearman correlation coefficient=-0.388). This phenomenon was more prominent in locals(-0.624 versus -0.175). Multivariable logistic regression was used as a dependent variable for the serious outcomes of foreign patients. The foreign patients(OR=1.413, p<0.001), intention, no insurance, age, sex, urban area, low blood pressure, decreased consciousness, transfer, acuity, and length of stay were statistically significant. Conclusion: This study showed that there is a health inequality for foreigners who came to the emergency room due to injury in Korea. Also, serious outcomes from injury in foreigners have been shown to be related to various causes including factors of the foreigner.
The European Programme for Ice Coring in Antarctica includes a comprehensive pre-site survey on the inland ice plateau of Dronning Maud Land, Antarctica. The German glaciological programme during the 1997/98 field season was carried out along a 1200 km traverse on Amundsenisen and involved sampling the snow cover in pits and by shallow firn cores. This paper focuses on the accumulation studies. The cores were dated by dielectric-profiling and continuous-flow analysis. Distinct volcanogenic peaks and seasonal signals in the profiles served to establish a depth time-scale. The eruptions of Krakatoa, Tambora, an unknown volcano, Kuwae and El Chichon are well-documented in the ice. Variations of the accumulation rates over different times were inferred from the depth time-scales. A composite record of accumulation rates for the last 200 years was produced by stacking 12 annually resolved records. According to this, accumulation rates decreased in the 19th century and increased in the 20th century. The recent values are by no means extraordinary, as they do not exceed the values at the beginning of the 19th century. Variations in accumulation rates are most probably linked to temperature variations indicated in δ18O records from Amundsenisen.
Access to nutritious foods is key to achieving health promotion goals. While there is evidence that nutritious food access is complex, measures assessing multiple domains of access, including spatial-temporal, economic, social, service delivery and personal, are lacking. The current study evaluates psychometric properties of scales designed to measure perceptions of multiple domains of nutritious food access among low-income populations.
A cross-sectional survey was conducted in 2015. Eighty-one items were selected or developed to represent five domains of nutritious food access for food shopping overall and specific to shopping at farmers’ markets. Evaluation of the items included exploratory factor analysis within each domain and internal consistency reliability for each of the sub-scales.
Data were collected in seventeen urban neighbourhoods in Greater Cleveland, Ohio, USA that have high levels of poverty. All participants had access to at least one farmers’ market within 1·6 km (1 mile) of their home to standardize spatial access to nutritious foods.
Adults (n 304) receiving Supplemental Nutrition Assistance Program benefits.
Each domain included multiple sub-domains: spatial-temporal (four), service delivery (two), economic (two), social (three) and personal (three), for a total of fourteen subdomains. The internal consistency reliability for one of the sub-domains was outstanding (>0·90), seven were excellent (0·80–0·89), five were very good (0·70–0·79) and one scale had poor reliability (0·58).
Multiple sub-domains of nutritious food access can be assessed using short measures that have been tested for internal consistency. These measures are suitable for assessing the complex phenomena of nutritious food access among low-income populations.
White Glacier is a valley glacier at 79.5°N with an area of 38.7 km2. Its mass balance has been measured, over 32 years with a 3 year gap, by standard techniques using the stratigraphic system with a stake density of the order of one stake per km2. Errors in stake mass balance are about ±(200–250) mm, due largely to the local unrepresentativeness of measurements. Errors in the whole-glacier mass balance B are of the same order as single-slake errors. However, the lag-1 autocorrelation in the time series of B is effectively zero, so it consists of independent random samples, and the error in the long-term “balance normal” 〈B〉 is noticeably less. 〈B〉 is −100 ± 48 mm. The equilibrium-line altitude (ELA) averages 970 m. with a range of 470–1400 m. Mass balance is well correlated with ELA, but detailed modelling shows that the equilibrium line is undetectable on visible-band satellite images. A reduced network of a few stakes could give acceptable but less accurate estimates of the mass balance, as could estimates based on data from a weather station 120 km away. There is no evidence of a trend in the mass balance of White Glacier. To detect a climatologically plausible trend will require a ten-fold reduction of measurement error, a conclusion which may well apply to most estimates of mass balance based on similar stake densities.
Little is known about how behavioural and psychological symptoms of dementia (BPSD) manifest in the general hospital. The aim was to examine the frequency of BPSD in general hospitals and their associations with nursing staff distress and complications in care.
Cross-sectional representative study with 1469 patients aged ≥65, including 270 patients with dementia, of 33 randomly selected general hospitals in Germany. BPSD and complications were reported by nurses.
Overall frequency of BPSD was higher in patients with dementia (76%) than without (38%). The most frequent symptoms in patients with dementia were nighttime disturbances (38%), depression (29%) and aberrant motor behaviour (28%) and the most distressing symptoms for nursing staff were delusions, aggression and nighttime disturbances. The overall frequency of BPSD increased from 67% in mild dementia, to 76% in moderate dementia and to 88% in severe dementia. The most frequent symptoms in patients without dementia were depression (19%), nighttime disturbances (13%) and irritability (13%). The most distressing symptoms were aggression and delusions, while the same symptoms were consistently rated as less distressing than in patients with dementia. Factor analysis revealed three independent groups of BPSD that explained 45% of the total variance. First, expansive symptoms (aggression, irritability, nighttime disturbances, aberrant motor behaviour and disinhibition) were frequent, distressing for nursing staff and associated with many complications. Second, psychotic symptoms (delusions and hallucinations) were infrequent, distressing and associated with some complications. Third, affective symptoms (apathy, anxiety and depression) were frequent, non-distressing and associated with few complications. The results did not change when cases with delirium were excluded from both groups.
BPSD are common in older hospital patients with dementia and associated with considerable distress in nursing staff, as well as a wide range of special treatments needs and additional behavioural and medical complications. Management strategies are needed to improve the situation for both patients and hospital staff.
We present recent observation results of Sgr A* at millimeter obtained with VLBI arrays in Korea and Japan.
7 mm monitoring of Sgr A* is part of our AGN large project. The results at 7 epochs during 2013-2014, including high resolution maps, flux density and two-dimensional size measurements are presented. The source shows no significant variation in flux and structure related to the G2 encounter in 2014. According to recent MHD simulations by kawashima et al., flux and magnetic field energy can be expected to increase several years after the encounter; We will keep our monitoring in order to test this prediction.
Astrometric observations of Sgr A* were performed in 2015 at 7 and 3.5 millimeter simultaneously. Source-frequency phase referencing was applied and a combined ”core-shift” of Sgr A* and a nearby calibrator was measured. Future observations and analysis are necessary to determine the core-shift in each source.
Objectives: One of the most prominent features of schizophrenia is relatively lower general cognitive ability (GCA). An emerging approach to understanding the roots of variation in GCA relies on network properties of the brain. In this multi-center study, we determined global characteristics of brain networks using graph theory and related these to GCA in healthy controls and individuals with schizophrenia. Methods: Participants (N=116 controls, 80 patients with schizophrenia) were recruited from four sites. GCA was represented by the first principal component of a large battery of neurocognitive tests. Graph metrics were derived from diffusion-weighted imaging. Results: The global metrics of longer characteristic path length and reduced overall connectivity predicted lower GCA across groups, and group differences were noted for both variables. Measures of clustering, efficiency, and modularity did not differ across groups or predict GCA. Follow-up analyses investigated three topological types of connectivity—connections among high degree “rich club” nodes, “feeder” connections to these rich club nodes, and “local” connections not involving the rich club. Rich club and local connectivity predicted performance across groups. In a subsample (N=101 controls, 56 patients), a genetic measure reflecting mutation load, based on rare copy number deletions, was associated with longer characteristic path length. Conclusions: Results highlight the importance of characteristic path lengths and rich club connectivity for GCA and provide no evidence for group differences in the relationships between graph metrics and GCA. (JINS, 2016, 22, 240–249)
Obsessive–compulsive disorder (OCD) has been associated with abnormal cognitive and emotional functions and these dysfunctions may be dependent on the disruption of dynamic interactions within neuronal circuits associated with emotion regulation. Although several studies have shown the aberrant cognitive–affective processing in OCD patients, little is known about how to characterize effective connectivity of the disrupted neural interactions. In the present study, we applied effective connectivity analysis using dynamic causal modeling to explore the disturbed neural interactions in OCD patients.
A total of 20 patients and 21 matched healthy controls performed a delayed-response working memory task under emotional or non-emotional distraction while undergoing functional magnetic resonance imaging.
During the delay interval under negative emotional distraction, both groups showed similar patterns of activations in the amygdala. However, under negative emotional distraction, the dorsolateral prefrontal cortex (DLPFC) and the orbitofrontal cortex (OFC) exhibited significant differences between groups. Bayesian model averaging indicated that the connection from the DLPFC to the OFC was negatively modulated by negative emotional distraction in patients, when compared with healthy controls (p < 0.05, Bonferroni-corrected).
Exaggerated recruitment of the DLPFC may induce the reduction of top-down prefrontal control input over the OFC, leading to abnormal cortico-cortical interaction. This disrupted cortico-cortical interaction under negative emotional distraction may be responsible for dysfunctions of cognitive and emotional processing in OCD patients and may be a component of the pathophysiology associated with OCD.
The disease- and mortality-related difference between biological age based on DNA methylation and chronological age (Δage) has been found to have approximately 40% heritability by assuming that the familial correlation is only explained by additive genetic factors. We calculated two different Δage measures for 132 middle-aged female twin pairs (66 monozygotic and 66 dizygotic twin pairs) and their 215 sisters using DNA methylation data measured by the Infinium HumanMethylation450 BeadChip arrays. For each Δage measure, and their combined measure, we estimated the familial correlation for MZ, DZ and sibling pairs using the multivariate normal model for pedigree analysis. We also pooled our estimates with those from a former study to estimate weighted average correlations. For both Δage measures, there was familial correlation that varied across different types of relatives. No evidence of a difference was found between the MZ and DZ pair correlations, or between the DZ and sibling pair correlations. The only difference was between the MZ and sibling pair correlations (p < .01), and there was marginal evidence that the MZ pair correlation was greater than twice the sibling pair correlation (p < .08). For weighted average correlation, there was evidence that the MZ pair correlation was greater than the DZ pair correlation (p < .03), and marginally greater than twice the sibling pair correlation (p < .08). The varied familial correlation of Δage is not explained by additive genetic factors alone, implying the existence of shared non-genetic factors explaining variation in Δage for middle-aged women.
This study examined the hypothesis that a brief, strengths-based home visiting strategy can promote positive engagement between caregiver and child and thereby reduce various forms of early childhood neglect. A total of 731 low-income families receiving services through the Women, Infants, and Children nutritional supplement program were randomized to the Women, Infants, and Children as usual or the Family Check-Up intervention. Assessments and intervention services were delivered in the home environment at ages 2, 3, 4, and 5. During the assessments, staff videotaped caregiver–child interactions and rated various features of the home environment, including the physical appropriateness of the home setting for children. Trained observers later coded the videotapes, unaware of the family's intervention condition. Specific caregiver–child interaction patterns were coded and macroratings were made of the caregiver's affection, monitoring, and involvement with the child. An intention to treat design revealed that randomization to the Family Check-Up increased duration of positive engagement between caregivers and children by age 3, which in turn was prognostic of less neglect of the child at age 4, controlling for family adversity. It was also found that family adversity moderated the impact of the intervention, such that the families with the most adverse circumstances were highly responsive to the intervention. Families with the highest levels of adversity exhibited the strongest mediation between positive engagement and reduction of neglect. Findings are discussed with respect to developmental theory and their potential implications for a public health approach to the prevention of early childhood maltreatment.
Experimental data are presented showing maximum carbon C6+ ion energies obtained from nm-scaled targets in the relativistic transparent regime for laser intensities between 9 × 1019 and 2 × 1021 W/cm2. When combined with two-dimensional particle-in-cell simulations, these results show a steep linear scaling for carbon ions with the normalized laser amplitude a0 (
$a_0 \propto \sqrt ( I)$
). The results are in good agreement with a semi-analytic model that allows one to calculate the optimum thickness and the maximum ion energies as functions of a0 and the laser pulse duration τλ for ion acceleration in the relativistic-induced transparency regime. Following our results, ion energies exceeding 100 MeV/amu may be accessible with currently available laser systems.
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.