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The science of studying diamond inclusions for understanding Earth history has developed significantly over the past decades, with new instrumentation and techniques applied to diamond sample archives revealing the stories contained within diamond inclusions. This chapter reviews what diamonds can tell us about the deep carbon cycle over the course of Earth’s history. It reviews how the geochemistry of diamonds and their inclusions inform us about the deep carbon cycle, the origin of the diamonds in Earth’s mantle, and the evolution of diamonds through time.
A new fossil site in a previously unexplored part of western Madagascar (the Beanka Protected Area) has yielded remains of many recently extinct vertebrates, including giant lemurs (Babakotia radofilai, Palaeopropithecus kelyus, Pachylemur sp., and Archaeolemur edwardsi), carnivores (Cryptoprocta spelea), the aardvark-like Plesiorycteropus sp., and giant ground cuckoos (Coua). Many of these represent considerable range extensions. Extant species that were extirpated from the region (e.g., Prolemur simus) are also present. Calibrated radiocarbon ages for 10 bones from extinct primates span the last three millennia. The largely undisturbed taphonomy of bone deposits supports the interpretation that many specimens fell in from a rock ledge above the entrance. Some primates and other mammals may have been prey items of avian predators, but human predation is also evident. Strontium isotope ratios (87Sr/86Sr) suggest that fossils were local to the area. Pottery sherds and bones of extinct and extant vertebrates with cut and chop marks indicate human activity in previous centuries. Scarcity of charcoal and human artifacts suggests only occasional visitation to the site by humans. The fossil assemblage from this site is unusual in that, while it contains many sloth lemurs, it lacks ratites, hippopotami, and crocodiles typical of nearly all other Holocene subfossil sites on Madagascar.
Previous studies using resting-state functional neuroimaging have revealed alterations in whole-brain images, connectome-wide functional connectivity and graph-based metrics in groups of patients with schizophrenia relative to groups of healthy controls. However, it is unclear which of these measures best captures the neural correlates of this disorder at the level of the individual patient.
Here we investigated the relative diagnostic value of these measures. A total of 295 patients with schizophrenia and 452 healthy controls were investigated using resting-state functional Magnetic Resonance Imaging at five research centres. Connectome-wide functional networks were constructed by thresholding correlation matrices of 90 brain regions, and their topological properties were analyzed using graph theory-based methods. Single-subject classification was performed using three machine learning (ML) approaches associated with varying degrees of complexity and abstraction, namely logistic regression, support vector machine and deep learning technology.
Connectome-wide functional connectivity allowed single-subject classification of patients and controls with higher accuracy (average: 81%) than both whole-brain images (average: 53%) and graph-based metrics (average: 69%). Classification based on connectome-wide functional connectivity was driven by a distributed bilateral network including the thalamus and temporal regions.
These results were replicated across the three employed ML approaches. Connectome-wide functional connectivity permits differentiation of patients with schizophrenia from healthy controls at single-subject level with greater accuracy; this pattern of results is consistent with the ‘dysconnectivity hypothesis’ of schizophrenia, which states that the neural basis of the disorder is best understood in terms of system-level functional connectivity alterations.
Great Plains yucca is a native species that competes with forage plants for space and water and at high densities may warrant control. The objective of this study was to determine the efficacy of seven herbicides applied in the spring or fall for Great Plains yucca control. Six foliar herbicides applied by ground application at 187 L ha−1 spray volume, one herbicide applied to individual plant whorls, and a nontreated check were established in June and September of 2009 and 2011. Percent mortality was determined 12 to 16 mo after herbicide application. Most herbicides gave similar control between the 2 yr, with triclopyr in diesel applied to individual plant whorls at 10 g L−1 providing the greatest control at 83%. Most herbicides applied in June near the blooming stage of Great Plains yucca were more effective than September treatments. June treatments providing the greatest reduction in yucca densities were metsulfuron + dicamba + 2,4-D amine + 2,4-D low volatile ester (LVE) at 21 + 113 + 325 + 431 g ae ha−1, metsulfuron + aminopyralid + triclopyr at 49 + 9 + 227 g ha−1, metsulfuron + chlorsulfuron + 2,4-D LVE at 34 + 11 + 431 g ha−1, and metsulfuron + aminopyralid + 2,4-D LVE at 49 + 9 + 431 g ha−1. A single application of a foliar herbicide provided a maximum of 72% mortality of Great Plains yucca, suggesting that repeat application may be necessary to achieve optimum control.
Most studies underline the contribution of heritable factors for psychiatric disorders. However, heritability estimates depend on the population under study, diagnostic instruments, and study designs that each has its inherent assumptions, strengths, and biases. We aim to test the homogeneity in heritability estimates between two powerful, and state of the art study designs for eight psychiatric disorders.
We assessed heritability based on data of Swedish siblings (N = 4 408 646 full and maternal half-siblings), and based on summary data of eight samples with measured genotypes (N = 125 533 cases and 208 215 controls). All data were based on standard diagnostic criteria. Eight psychiatric disorders were studied: (1) alcohol dependence (AD), (2) anorexia nervosa, (3) attention deficit/hyperactivity disorder (ADHD), (4) autism spectrum disorder, (5) bipolar disorder, (6) major depressive disorder, (7) obsessive-compulsive disorder (OCD), and (8) schizophrenia.
Heritability estimates from sibling data varied from 0.30 for Major Depression to 0.80 for ADHD. The estimates based on the measured genotypes were lower, ranging from 0.10 for AD to 0.28 for OCD, but were significant, and correlated positively (0.19) with national sibling-based estimates. When removing OCD from the data the correlation increased to 0.50.
Given the unique character of each study design, the convergent findings for these eight psychiatric conditions suggest that heritability estimates are robust across different methods. The findings also highlight large differences in genetic and environmental influences between psychiatric disorders, providing future directions for etiological psychiatric research.
The study of cultural stability requires a knowledge of cultural development over a reasonably long span of time. The definition of this time perspective is one of the major contributions of archaeology to the study of culture. The archaeologist therefore should be in a position to make a significant contribution to the appraisal of the stability problem itself. However, the lack of a commonly accepted anthropological definition of the concept of cultural stability imposes semantic difficulties which hinder the determination of practical limits for the stability- instability problem area. Moreover, the nature of the data available to the archaeologist conditions the kind of contribution he can make.
Cycads in the Zamiaceae are well known for their host-specific insect pollination mutualisms. Pollination of Cycas in the sister family Cycadaceae is less well-documented, with beetle pollination possibly coexisting with a limited potential for wind pollination, a hypothesis we tested for C. ophiolitica in Central Queensland, Australia. Cones were associated with three species of beetle: an undescribed weevil (Curculionidae), Hapalips sp. (Erotylidae) and Ulomoides sp. (Tenebrionidae). Pollination-vector exclusion experiments compared the pollination success (quantified as % ovules pollinated per cone) of control cones against bagged or netted cones that excluded wind or insects respectively (n = 10 for all treatments). Insects do pollinate C. ophiolitica in the absence of wind, the median (first quartile-third quartile) pollination success of control plants being 83.7% (60.8–87.2%) while bagged cones, from which wind, but not insects, were excluded, pollinated at 52.9% (19.5–74.8%). For netted cones, (excluding insects but not wind), pollination fell to 12.6% (10.9–45.9%). Airborne pollen (as quantified by capture on a series of adhesive pollen traps) decreased rapidly with distance from male cones, potentially becoming ineffective for wind pollination at ~5 m. Airborne pollen load in the vicinity of female cones, and distance of females from neighbouring males, suggests wind pollination may occur sporadically, but only at high spatial densities. Although Cycas appears to be primarily insect pollinated, this limited potential for ambophily may be significant given the history of dispersal and pollinator host shifts among these cycads.
Sex differences in the incidence of infections may indicate different risk factors and behaviour but have not been analysed across pathogens. Based on 3.96 million records of 33 pathogens in Germany, notified from 2001 to 2013, we applied Poisson regression to generate age-standardised incidence rate ratios and assessed their distribution across age and sex. The following trends became apparent: (a) pathogens with male incidence preponderance at infant and child age (meningococcal disease (incidence rate ratio (IRR) = 1.19, 95% CI 1.03–1.38, age = 0–4); influenza (IRR = 1.09, 95% CI 1.06–1.13, age = 0–4)), (b) pathogens with sex-switch in incidence preponderance at puberty (e.g. norovirus (IRR = 1.10, 95% CI 1.02–1.19 in age = 5–14, IRR = 0.96, 95% CI 0.93–0.99, age ⩾ 60), (c) pathogens with general male incidence preponderance (bacterial/parasitic infections with campylobacter, Yersinia and Giardia), (d) pathogens with male incidence preponderance at juvenile and adult age (sexually transmitted or vector-borne infections (combined-IRR = 2.53, 95% CI 2.36–2.71, age = 15–59), (e) pathogens with male preponderance at older age (tick-borne encephalitis - IRR = 2.75, 95% CI 1.21–6.24, listeriosis - IRR = 2.06, 95% CI 1.38–3.06, age ⩾ 60). Risk factor concepts only partly serve to interpret similarities of grouped infections, i.e. transmission-related explanations and sex-specific exposures not consistently explain the pattern of food-borne infections (b). Sex-specific differences in infectious disease incidence are well acknowledged regarding the sexually transmitted diseases. This has led to designing gender-specific prevention strategies. Our data suggest that for infections with other transmission routes, gender-specific approaches can also be of benefit and importance.
An internationally approved and globally used classification scheme for the diagnosis of CHD has long been sought. The International Paediatric and Congenital Cardiac Code (IPCCC), which was produced and has been maintained by the International Society for Nomenclature of Paediatric and Congenital Heart Disease (the International Nomenclature Society), is used widely, but has spawned many “short list” versions that differ in content depending on the user. Thus, efforts to have a uniform identification of patients with CHD using a single up-to-date and coordinated nomenclature system continue to be thwarted, even if a common nomenclature has been used as a basis for composing various “short lists”. In an attempt to solve this problem, the International Nomenclature Society has linked its efforts with those of the World Health Organization to obtain a globally accepted nomenclature tree for CHD within the 11th iteration of the International Classification of Diseases (ICD-11). The International Nomenclature Society has submitted a hierarchical nomenclature tree for CHD to the World Health Organization that is expected to serve increasingly as the “short list” for all communities interested in coding for congenital cardiology. This article reviews the history of the International Classification of Diseases and of the IPCCC, and outlines the process used in developing the ICD-11 congenital cardiac disease diagnostic list and the definitions for each term on the list. An overview of the content of the congenital heart anomaly section of the Foundation Component of ICD-11, published herein in its entirety, is also included. Future plans for the International Nomenclature Society include linking again with the World Health Organization to tackle procedural nomenclature as it relates to cardiac malformations. By doing so, the Society will continue its role in standardising nomenclature for CHD across the globe, thereby promoting research and better outcomes for fetuses, children, and adults with congenital heart anomalies.
John Bynner, Emeritus Professor of Social Sciences in Education at the London Institute of Education,
Glen H. Elder, Odum Distinguished Research Professor of Sociology at University of North Carolina at Chapel Hill,
Walter R. Heinz, Emeritus Professor of Sociology and Psychology at the University of Bremen, Germany,
Ingrid Schoon, Professor of Human Development and Social Policy at the University College London Institute of Education
What have we learned about the changing nature of youth transitions and the effect of the Great Recession on them? In this final chapter we draw conclusions and seek further insights from the evidence presented. First we give a brief overview, taking the discussion back to the initial questions about the recession effects to which the preceding chapters were directed. Second, we discuss the evidence in the light of key themes of contemporary youth research and draw out their intersection with life course theory. We then consider the theoretical and policy insights to be gained from the evidence reported. Our discussion focuses on young people in the USA, the UK, and Germany, but also takes into account developments across a range of industrialized countries.
What was the impact of the Great Recession on young people making the transition to independent adulthood? The overall conclusion to be drawn is that the Great Recession was a significant but not principal influence on young people's changing life course post-2007. Better to characterize it as a major economic shock that intensified the impact of preexisting economic and social processes on young people's lives. Originating principally in Western countries in the period of technological transformation and de-industrialization of the late 1970s, as the contributors to the book show, these effects presented new obstacles to entering and sustaining employment within the adult labor market. There were also wider repercussions for functioning in the family and other life domains. Although the short-term effects may have been modest, they might be followed by more serious outcomes and long-term scarring effects. There could also be lagged effects (i.e., a delay between the exposure and onset of adjustment problems) and therefore continued monitoring of life chances for young people is necessary.
The recession effects varied with each successive cohort embarking on the transition to independent adulthood, i.e., they differed for different age groups, for different countries, and between different sections of the youth population. Younger cohorts, aged 15–18 when the effects of the Great Recession began to be felt, faced heightened difficulties in gaining entry to jobs or to the vocational education and training (VET) routes that previously ensured access to them.
The Mars Society is an international private organisation advocating the exploration and settlement of Mars. Part of its mission involves selecting areas for Martian analogue research, to test hardware, technology, strategies and human factors relevant to sending people to Mars. Mars Society Australia has selected an area in the Arkaroola region in the Flinders Ranges as the site for the first Australian analogue facility. The facility will be an invaluable public education and outreach tool for Australian science, focusing on astrobiology, and its role in future human Mars missions; demonstrating Australian contributions to astrobiology related science and work on terrestrial analogues to Martian environments.
Buried surface hoar and near-surface faceted crystals are known to lead to deadly avalanches. Over the course of three winter seasons a field investigation detailing the environmental conditions leading to the formation of these crystals was performed. Weather stations on north- and south-facing aspects were established. The weather data were accompanied by detailed daily observations and grain-scale photographs of the snow surface. During the three seasons, 35 surface hoar and 47 near-surface facets events were recorded. The mean weather conditions for the entire dataset (all three seasons and both stations) were compared to the nights when surface hoar formed. The comparison yielded five parameters that were statistically linked to the formation of surface hoar: incoming longwave radiation, snow surface temperature, wind velocity, relative humidity and the air/snow temperature difference. A similar comparison between the daytime mean values for all days with near-surface facet events revealed three parameters with statistically significant differences. Thus, these parameters (short- and longwave radiation and relative humidity) could be statistically linked to facet formation. This research also suggests that environmental conditions in the daytime hours before and after surface hoar formation are statistically similar to the conditions causing near-surface facet formation.
Optical positions of some 30 radio stars derived from 12 months of HIPPARCOS measurements are compared with their radio positions obtained with the Very Large Array (VLA). — Once the lengths of arcs between optical and radio positions of pairs of stars are calculated the differences of the arcs are formed. They provide an estimate of the coincidence of the optical and radio emission centres. — From the comparison of optical and radio positions infinitesimal rotation angles of the HIPPARCOS frame with respect to the VLA extragalactic reference frame are determined by rigid rotations. After taking account of the relative orientation of the frames the standard deviations of the remaining residuals are approximately of the order of the VLA observation errors, thus demonstrating the reliability of the HIPPARCOS results. However, they also indicate some data noise very likely caused by the low accuracy of optical proper motions used to bridge the HIPPARCOS-radio epoch differences up to 9 years, and possible discrepancies of radio-optical emission centres of some stars.
Using the first 12 months of HIPPARCOS mission data already reduced, a synthesis solution was obtained by both CERGA and ARI teams. The reduction includes two steps. In the first one the origins of individual reference circles are determined, thus constituting the HIPPARCOS celestial reference frame. This solution uses a subset of some 30 000 bright and evidently single stars in order to minimize possible corruptive effects on the system. In the second step, the abscissa measurements of all observed stars are substituted in the system and then processed star by star in a least squares adjustment providing the astrometric parameters (positions and parallaxes).
The results of sphere solution and astrometric parameter determination are discussed. In this context error ellipses and internal errors are calculated. External errors are derived by comparison with suitable astrometric catalogues. Especially, for estimating the external errors of the HIPPARCOS measured FK5 stars the instrumental system was tied to the FK5 system by rigid rotations followed by comparisons of the positions with those of FK5. The mean internal errors of the HIPPARCOS positions of FK5 stars is 1.5 milliarcseconds (mas) while the standard deviation of the differences HIPPARCOS minus FK5 reaches 90 mas. For the 5022 measured parallaxes the mean internal and external errors are 3.8 mas and 16.7 mas, respectively. — The results of precision and comparisons with external data show that the accuracy predicted for the final catalogue can be reached.
Variability of the [OIII]4363/4340 H γ ratio in IC 4007 was established in 1956 by William Liller and L.H. Aller who attributed the changes to a gradual decrease of electron density with time. Subsequent 4363/4340 ratio fluctuations negated this explanation. Ferland pointed out that small changes in the radiative flux of the Planetary nebula nucleus (PNN) could explains the variations. Our pervious study emphasized IUE observations, here we compare high dispersion spectra obtained with the Hamilton Echelle Spectrograph with previous measurements to asses line intensity variations. Emission line variability in PNN spectra as noted by Mendez et al. (1988) and by other for HeII 4686 in NGC 6572 may offer significant clues. PNN 4686 appeared by 1990 in IC 4997. Possibly both of these PNN may be evolving into Wolf-Rayet objects, but this development does not necessarily imply that the nebular excitation will increase with time.
The salient features of quasi-periodic oscillations (QPO) observed in type 2 bursts and in the persistent emission from the Rapid Burster are discussed. In addition, a brief review is given of the models that have recently been proposed to explain high-frequency QPO observed in several bright low-mass X-ray binaries. We do not yet know the mechanism(s) of the QPO, not even whether they are magnetospheric in origin. However, some of the proposed ideas could well be relevant to the various rather complex aspects of the QPO. It is likely that more than one mechanism is at work.
The usefulness of Schmidt plates for measuring astrometric positions of extragalactic radio sources with an average uncertainty of less than 0.3 arcseconds is emphasized in the discussion of the results on 50 optical counterparts and by the comparison with corresponding positions obtained through radio interferometry.
From a list of 275 confirmed or potential radio stars proposed to the Hipparcos input catalogue we selected about 80 objects which either lie outside the conventional astrometric catalogues or which are SAO-stars having declinations less than −17°. The positions of these stars were derived from measurements on POSS, SRC, and ESO(B) plates using reference stars from the SAO catalogue for the northern candidates, and from the Perth 70 catalogue for the southern candidates, respectively. The epochs of our positions fall in the middle of the fifties and seventies. For 52 stars other epochs were supplied by observations taken from literature. We determine proper motions from these positions which provide a base-line up to 35 years.