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Laterite profiles developed from granite in southwestern Australia were studied by scanning electron microscopy. The morphology of soil materials reflects the mineralogy of secondary minerals formed from feldspar. In the saprolite, etched feldspar surfaces are coated with kaolinite or radiating, spherical aggregates of tubular halloysite. In the lower pallid zone these minerals have replaced most of the feldspar. In the upper pallid zone a porous framework has developed consisting mainly of quartz and gibbsite with 5-/μm euhedral gibbsite crystals in voids. Halloysite crystals in the upper pallid zone are partly unrolled and have splayed ends. Differences in mineralogy and morphology between profiles are thought to be due to variations in the intensity of leaching.
Feldspars in granitic saprolite in southwestern Australia have altered to halloysite, kaolinite, and gibbsite with no evidence of noncrystalline material. The secondary minerals are commonly present as intimate mixtures within altered feldspar grains, but discrete zones of gibbsite or halloysite-kaolinite also are present. Variations in the chemical microenvironment within micrometer-size zones in grains apparently controlled the type and distribution of secondary minerals. The alteration of both plagioclase and alkali feldspars involved congruent dissolution by soil solution and crystallization of halloysite, kaolinite, and gibbsite from this solution. Highly altered feldspar grains consist of etched feldspar fragments embedded within a highly porous framework of subhedral to euhedral platy crystals of kaolinite and gibbsite, or of spherical and felted aggregates of halloysite.
Emotional problems, especially anxiety, have become increasingly common in recent generations. Few population-based studies have examined trajectories of emotional problems from early childhood to late adolescence or investigated differences in psychiatric and functional outcomes.
Methods
Using the Avon Longitudinal Study of Parents and Children (ALSPAC, n = 8286, 50.4% male), we modeled latent class growth trajectories of emotional problems, using the parent-reported Strength and Difficulties Questionnaire emotional scale (SDQ-E) on seven occasions (4–17 years). Psychiatric outcomes in young adulthood (21–25 years) were major depressive disorder (MDD), generalized anxiety disorder (GAD), and self-harm. Functional outcomes were exam attainment, educational/occupational status, and social relationship quality.
Results
We identified four classes of emotional problems: low (67.0%), decreasing (18.4%), increasing (8.9%), and persistent (5.7%) problems. Compared to those in the low class, individuals with decreasing emotional problems were not at elevated risk of any poor adult outcome. Individuals in the increasing and persistent classes had a greater risk of adult MDD (RR: 1.59 95% CI 1.13–2.26 and RR: 2.25 95% CI 1.49–3.41) and self-harm (RR: 2.37 95% CI 1.91–2.94 and RR: 1.87 95% CI 1.41–2.48), and of impairment in functional domains. Childhood sleep difficulties, irritability, conduct and neurodevelopmental problems, and family adversity were associated with a persistent course of emotional problems.
Conclusions
Childhood emotional problems were common, but those whose symptoms improved over time were not at increased risk for adverse adult outcomes. In contrast, individuals with persistent or adolescent-increasing emotional problems had a higher risk of mental ill-health and social impairment in young adulthood which was especially pronounced for those with persistent emotional problems.
Female fertility is a complex trait with age-specific changes in spontaneous dizygotic (DZ) twinning and fertility. To elucidate factors regulating female fertility and infertility, we conducted a genome-wide association study (GWAS) on mothers of spontaneous DZ twins (MoDZT) versus controls (3273 cases, 24,009 controls). This is a follow-up study to the Australia/New Zealand (ANZ) component of that previously reported (Mbarek et al., 2016), with a sample size almost twice that of the entire discovery sample meta-analysed in the previous article (and five times the ANZ contribution to that), resulting from newly available additional genotyping and representing a significant increase in power. We compare analyses with and without male controls and show unequivocally that it is better to include male controls who have been screened for recent family history, than to use only female controls. Results from the SNP based GWAS identified four genomewide significant signals, including one novel region, ZFPM1 (Zinc Finger Protein, FOG Family Member 1), on chromosome 16. Previous signals near FSHB (Follicle Stimulating Hormone beta subunit) and SMAD3 (SMAD Family Member 3) were also replicated (Mbarek et al., 2016). We also ran the GWAS with a dominance model that identified a further locus ADRB2 on chr 5. These results have been contributed to the International Twinning Genetics Consortium for inclusion in the next GWAS meta-analysis (Mbarek et al., in press).
Studies have demonstrated that decreases in slow-wave activity (SWA) predict decreases in depressive symptoms in those with major depressive disorder (MDD), suggesting that there may be a link between SWA and mood. The aim of the present study was to determine if the consequent change in SWA regulation following a mild homeostatic sleep challenge would predict mood disturbance.
Methods
Thirty-seven depressed and fifty-nine healthy adults spent three consecutive nights in the sleep laboratory. On the third night, bedtime was delayed by 3 h, as this procedure has been shown to provoke SWA. The Profile of Mood States questionnaire was administered on the morning following the baseline and sleep delay nights to measure mood disturbance.
Results
Results revealed that following sleep delay, a lower delta sleep ratio, indicative of inadequate dissipation of SWA from the first to the second non-rapid eye movement period, predicted increased mood disturbance in only those with MDD.
Conclusions
These data demonstrate that in the first half of the night, individuals with MDD who have less SWA dissipation as a consequence of impaired SWA regulation have greater mood disturbance, and may suggest that appropriate homeostatic regulation of sleep is an important factor in the disorder.
The eccentric orbits of the known extrasolar giant planets provide evidence that most planet-forming environments undergo violent dynamical instabilities. Here, we numerically simulate the impact of giant planet instabilities on planetary systems as a whole. We find that populations of inner rocky and outer icy bodies are both shaped by the giant planet dynamics and are naturally correlated. Strong instabilities – those with very eccentric surviving giant planets – completely clear out their inner and outer regions. In contrast, systems with stable or low-mass giant planets form terrestrial planets in their inner regions and outer icy bodies produce dust that is observable as debris disks at mid-infrared wavelengths. Fifteen to twenty percent of old stars are observed to have bright debris disks (at λ ~ 70μm) and we predict that these signpost dynamically calm environments that should contain terrestrial planets.
In order to see if aeration causes grain beetles to become peripherally distributed in bulks of grain, the positions of adults were recorded 7–10 days after they had been placed in the middle of vertical columns of wheat 1200 mm long and 80 mm in diameter. The columns were held at 10 or 25°C, and a downward current of air was passed through half of them. At 10°C, there were more adults of Oryzaephilus surinamensis (L.) at the ends and fewer at the centre of aerated than unaerated tubes when a high airflow was used, and at 25°C, a similar difference occurred when aeration caused cooling, dampening or drying of the grain. Dampening at 10°C and drying at 25°C caused there to be fewer adults of Sitophilus granarius (L.) at the ends and more at the centre of aerated than unaerated tubes. However, vibration at 10°C encouraged the dispersion of weevils. Rhyzopertha dominica (F.) scarcely moved at 10 or 25°C under either aerated or unaerated conditions.
This study examines psychological symptomatology in a cohort of 72 heart transplant recipients followed longitudinally during their first year post-transplant. In keeping with research on other domains of life stressors and illnesses, a central study goal was to identify pre-transplant and perioperative psychosocial factors associated with increased vulnerability to, and maintenance of, elevated psychological distress levels post-transplant. Average anxiety and depression levels, but not anger–hostility symptoms, were substantially elevated in the early post-transplant period, relative to normative data. Average symptom levels improved significantly over time, although one-third of the sample continued to have high distress levels at all follow-up assessments. Recipients with any of seven psychosocial characteristics at initial interview were particularly susceptible to continued high average distress levels over time: a personal history of psychiatric disorder prior to transplant; younger age; lower social support from their primary family caregiver; exposure to recent major life events involving loss; poor self-esteem; a poor sense of mastery; and use of avoidance coping strategies to manage health problems. Recipients without such factors showed improvement in average distress levels across the assessment period. These effects were stronger for anxiety than depressive symptoms, with the exception of a sizeable relationship between loss events and subsequent depression. The findings suggest that clinical interventions designed to minimize prolonged emotional distress post-transplant need to be closely tailored to heart recipients' initial psychosocial assets and liabilities.
A procedure for combining evidence from different biological assays is shown to be equivalent both to generalized least-squares and to maximum-likelihood estimation. By appropriate nesting of hypotheses, the likelihood function can be used to test the agreement between the assays and to obtain probability limits for the combined estimate of potency. The properties of these limits are examined, with particular reference to the situation, unusual but not impossible in practice, in which the values of relative potency that they define consist of several disjoint segments instead of a single interval. The connexion with general theory of estimating linear functional relations is pointed out.
Preliminary feeding experiments (Morris, Ferguson & Raymont, 1973) showed that Neomysis integer was capable of incorporating dietary labelled [1-14C]fatty acids (16:04 18:1,18:2,18:3) into its lipid. Radioactivity was observed in all the major fatty acids of Neomysis, including the polyunsaturated fatty acids. Neomysis could also convert dietary 14C-labelled starch into lipid, producing a range of fatty acids, including long-chain polyunsaturated acids, incorporated in both triglycerides and phospholipids. During these metabolic conversions, the mysid was observed to incorporate more radioactive14C into the phospholipid fraction with increase in the experimental feeding period.
By
Philip J. Armitage, JILA, 440 UCB, University of Colorado, Boulder, CO 80309, USA: Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309, USA,
W. K. M. Rice, Institute of Geophysics and Planetary Physics and Department of Earth Sciences, University of California, Riverside, CA 92521, USA
Edited by
Mario Livio, Space Telescope Science Institute, Baltimore,Kailash Sahu, Space Telescope Science Institute, Baltimore,Jeff Valenti, Space Telescope Science Institute, Baltimore
Gravitational torques between a planet and gas in the protoplanetary disk result in orbital migration of the planet, and modification of the disk surface density. Migration via this mechanism is likely to play an important role in the formation and early evolution of planetary systems. For masses comparable to those of observed giant extrasolar planets, the interaction with the disk is strong enough to form a gap, leading to coupled evolution of the planet and disk on a viscous time scale (Type II migration). Both the existence of hot Jupiters and the statistical distribution of observed orbital radii are consistent with an important role for Type II migration in the history of currently observed systems. We discuss the possibility of improving constraints on migration by including information on the host stars' metallicity, and note that migration could also form a population of massive planets at large orbital radii that may be indirectly detected via their influence on debris disks. For lower mass planets with Mp ~ M⊕, surface density perturbations created by the planet are small, and migration in a laminar disk is driven by an intrinsic and apparently robust asymmetry between interior and exterior torques. Analytic and numerical calculations of this Type I migration are in reasonable accord, and predict rapid orbital decay during the final stages of the formation of giant planet cores.
The current status of the stream-living insects and gastropods of the island of Gran Canaria in the Atlantic Canary Islands is documented. Data from semiquantitative kick samples taken in 11 streams are supplemented by non-standardized collecting in the same and ten additional streams. The kick samples included some 9,000 specimens of 98 taxa, and in total 123 taxa were recorded from the studied streams in 1994 and 1995. The stream fauna was dominated by Diptera with some 80 taxa, followed by Coleoptera with 37 species known from the island. The kick samples yielded 11-36 species per stream and visit, whereas up to 48 species were scored when all collecting methods were included. Local diversity given as Fisher's α ranged from 3.2 to 10.3. Clustering showed only weak spatial patterns and resulted in much higher similarities among localities when based on the semiquantitative samples than when based on presence/absence including records from all collecting methods. Species distributions among localities were not significantly nested. The faunal similarity with the adjacent island of Tenerife is striking. Six of the Tenerife species are seemingly absent from Gran Canaria, whereas Gran Canaria has 13 species not found in Tenerife. Most of the 22 aquatic insect species in Gran Canaria only known from older records, prefer lentic habitats not included in our study. All except one of the five species endemic to Gran Canaria are considered extinct or on the edge of extinction. Increased future extinction rates are predicted as a response of the extreme habitat loss, with only three permanent streams known on the island today.
The visual manifestation of the recent Hale-Bopp comet reminds us how telling are those rare objects which suddenly flare in the sky. One can suppose ancient people living by natural light were more compellingly struck by the sight of comets and supernovae, and understandably researchers seek images of them in the shapes of rock-art motifs. An absolute dating contradicts that supposition in respect of a presumed image of the visible supernova of AD 1054.
To determine the prevalence of aspergillosis in lymphoma patients housed in a protective environment while undergoing a bone marrow transplant or peripheral stem cell transplant and its relation to lymphoma type, type of transplant, period of neutropenia, method of diagnosis, species of Aspergillus, and the use of empiric amphotericin B.
Design:
Clinical, autopsy, and microbiology records were reviewed retrospectively to determine the presence or absence of invasive aspergillosis. All positive specimens underwent further review to determine parameters outlined above.
Setting:
The review took place at the University of Nebraska Medical Center with lymphoma patients housed in the oncology/hematology special care unit, which consists of 30 single-patient rooms under positive pressure with high-efficiency particulate air filtration.
Patients:
4 17 lymphoma patients admitted to the oncology/hematology special care unit who underwent 427 courses of high-dose chemotherapy with or without total body irradiation followed by a stem cell rescue.
Results:
Twenty-two cases (5.2%) of nosocomial invasive aspergillosis (14 caused by Aspergillus flavus, 2 by Aspergillus terreus, 2 by Aspergillus fumigatus, and 4 by characteristic histology) were diagnosed. The prevalence of disease according to transplant was 8.7% for allogeneic bone marrow transplant (2/23 treatments), 5.6% for autologous peripheral stem cell transplant (9/161), and 4.5% for autologous bone marrow transplant (11/243). Fifteen patients were presumptively diagnosed prior to death (68.2%) most commonly by histologic examination of skin biopsies. All 22 patients received amphotericin B therapy, 17 prior to aspergillosis diagnosis, and 7 (31.8%) survived. No patient with disseminated disease survived.
Conclusions:
Even when housing lymphoma patients undergoing myeloablative therapy in a protective environment containing high-efficiency particulate air filtration, there was a risk of developing aspergillosis. These data also showed that antemortem diagnosis with aggressive amphotericin B therapy was most effective in the management of infected lymphoma patients when engraftment occurred and the disease did not become disseminated.
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