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Cold-water coral reefs are biodiversity hotspots of the deep sea. The most dominant reef-building cold-water coral in the Atlantic is Lophelia pertusa, which builds vast and structurally complex habitats. Studying the behaviours of deep-sea species is challenging due to the technological difficulties in making prolonged observations in situ, so little is known about the behavioural ecology of this important species. Observations in laboratory studies can help to enhance our understanding of the range of behaviours these species exhibit. Here we present video evidence that the cold-water coral Lophelia pertusa is capable of producing mucus nets as part of their feeding strategy. This finding suggests that L. pertusa has a more diverse range of feeding strategies than previously thought.
Whereas genetic susceptibility increases the risk for major depressive disorder (MDD), non-genetic protective factors may mitigate this risk. In a large-scale prospective study of US Army soldiers, we examined whether trait resilience and/or unit cohesion could protect against the onset of MDD following combat deployment, even in soldiers at high polygenic risk.
Data were analyzed from 3079 soldiers of European ancestry assessed before and after their deployment to Afghanistan. Incident MDD was defined as no MDD episode at pre-deployment, followed by a MDD episode following deployment. Polygenic risk scores were constructed from a large-scale genome-wide association study of major depression. We first examined the main effects of the MDD PRS and each protective factor on incident MDD. We then tested the effects of each protective factor on incident MDD across strata of polygenic risk.
Polygenic risk showed a dose–response relationship to depression, such that soldiers at high polygenic risk had greatest odds for incident MDD. Both unit cohesion and trait resilience were prospectively associated with reduced risk for incident MDD. Notably, the protective effect of unit cohesion persisted even in soldiers at highest polygenic risk.
Polygenic risk was associated with new-onset MDD in deployed soldiers. However, unit cohesion – an index of perceived support and morale – was protective against incident MDD even among those at highest genetic risk, and may represent a potent target for promoting resilience in vulnerable soldiers. Findings illustrate the value of combining genomic and environmental data in a prospective design to identify robust protective factors for mental health.
Investigations of drinking behavior across military deployment cycles are scarce, and few prospective studies have examined risk factors for post-deployment alcohol misuse.
Prevalence of alcohol misuse was estimated among 4645 US Army soldiers who participated in a longitudinal survey. Assessment occurred 1–2 months before soldiers deployed to Afghanistan in 2012 (T0), upon their return to the USA (T1), 3 months later (T2), and 9 months later (T3). Weights-adjusted logistic regression was used to evaluate associations of hypothesized risk factors with post-deployment incidence and persistence of heavy drinking (HD) (consuming 5 + alcoholic drinks at least 1–2×/week) and alcohol or substance use disorder (AUD/SUD).
Prevalence of past-month HD at T0, T2, and T3 was 23.3% (s.e. = 0.7%), 26.1% (s.e. = 0.8%), and 22.3% (s.e. = 0.7%); corresponding estimates for any binge drinking (BD) were 52.5% (s.e. = 1.0%), 52.5% (s.e. = 1.0%), and 41.3% (s.e. = 0.9%). Greater personal life stress during deployment (e.g., relationship, family, or financial problems) – but not combat stress – was associated with new onset of HD at T2 [per standard score increase: adjusted odds ratio (AOR) = 1.20, 95% CI 1.06–1.35, p = 0.003]; incidence of AUD/SUD at T2 (AOR = 1.54, 95% CI 1.25–1.89, p < 0.0005); and persistence of AUD/SUD at T2 and T3 (AOR = 1.30, 95% CI 1.08–1.56, p = 0.005). Any BD pre-deployment was associated with post-deployment onset of HD (AOR = 3.21, 95% CI 2.57–4.02, p < 0.0005) and AUD/SUD (AOR = 1.85, 95% CI 1.27–2.70, p = 0.001).
Alcohol misuse is common during the months preceding and following deployment. Timely intervention aimed at alleviating/managing personal stressors or curbing risky drinking might reduce risk of alcohol-related problems post-deployment.
A considerable body of evidence suggests that early caregiving may affect the short-term functioning and longer term development of the hypothalamic–pituitary–adrenocortical axis. Despite this, most research to date has been cross-sectional in nature or restricted to relatively short-term longitudinal follow-ups. More important, there is a paucity of research on the role of caregiving in low- and middle-income countries, where the protective effects of high-quality care in buffering the child's developing stress regulation systems may be crucial. In this paper, we report findings from a longitudinal study (N = 232) conducted in an impoverished periurban settlement in Cape Town, South Africa. We measured caregiving sensitivity and security of attachment in infancy and followed children up at age 13 years, when we conducted assessments of hypothalamus–pituitary–adrenocortical axis reactivity, as indexed by salivary cortisol during the Trier Social Stress Test. The findings indicated that insecure attachment was predictive of reduced cortisol responses to social stress, particularly in boys, and that attachment status moderated the impact of contextual adversity on stress responses: secure children in highly adverse circumstances did not show the blunted cortisol response shown by their insecure counterparts. Some evidence was found that sensitivity of care in infancy was also associated with cortisol reactivity, but in this case, insensitivity was associated with heightened cortisol reactivity, and only for girls. The discussion focuses on the potentially important role of caregiving in the long-term calibration of the stress system and the need to better understand the social and biological mechanisms shaping the stress response across development in low- and middle-income countries.
Two broad aims drive weed science research: improved management and improved
understanding of weed biology and ecology. In recent years, agricultural
weed research addressing these two aims has effectively split into separate
subdisciplines despite repeated calls for greater integration. Although some
excellent work is being done, agricultural weed research has developed a
very high level of repetitiveness, a preponderance of purely descriptive
studies, and has failed to clearly articulate novel hypotheses linked to
established bodies of ecological and evolutionary theory. In contrast,
invasive plant research attracts a diverse cadre of nonweed scientists using
invasions to explore broader and more integrated biological questions
grounded in theory. We propose that although studies focused on weed
management remain vitally important, agricultural weed research would
benefit from deeper theoretical justification, a broader vision, and
increased collaboration across diverse disciplines. To initiate change in
this direction, we call for more emphasis on interdisciplinary training for
weed scientists, and for focused workshops and working groups to develop
specific areas of research and promote interactions among weed scientists
and with the wider scientific community.
We present new imaging data and archival multiwavelength observations of the little-studied emission nebula K 1-6 and its central star. Narrow-band images inHα (+[N II]) and [O III] taken with the Faulkes Telescope North reveal a stratified, asymmetric, elliptical nebula surrounding a central star which has the colours of a late G or early K-type subgiant or giant. GALEX ultraviolet images reveal a very hot subdwarf or white dwarf coincident in position with this star. The cooler, optically dominant star is strongly variable with a period of 21.312± 0.008 days, and is possibly a high-amplitude member of the RS CVn class, although an FK Com classification is also possible. Archival ROSAT data provide good evidence that the cool star has an active corona. We conclude that K 1-6 is most likely an old bona fide planetary nebula at a distance of ∼1.0 kpc, interacting with the interstellar medium, and containing a binary or ternary central star. The observations and data analyses reported in this paper were conducted in conjunction with Year 11 high school students as part of an Australian Research Council Linkage Grant science education project, denoted Space To Grow, conducted jointly by professional astronomers, educational researchers, teachers, and high-school students.
Three models were used to look at the Southern Ocean Ross Sea sector circulation and hydrography. Two were climate models of low (1°) to intermediate resolution (1/3°), and one was an operational high resolution (1/10°) ocean model. Despite model differences (including physics and forcing), mean and monthly variability aspects of off-shelf circulation are consistently represented, and could imply bathymetric constraints. Western and eastern cyclonic gyral systems separated by shallow bathymetry around 180°E redistributing water between the wider Southern Ocean and the Ross Sea are found. Some model seasonal gyral transports increase as the Antarctic Circumpolar Current transport decreases. Model flows at 900 m at the gyral eastern end compare favourably with float data. On-shelf model depth-averaged west–east flow is relatively consistent with that reconstructed from longline fishing records. These flows have components associated with isopycnal gradients in both light and dense waters. The climate models reproduce characteristic isopycnal layer inflections (‘V’s) associated with the observed Antarctic Slope Front and on-shelf deep water formation, and these models transport some 4 Sv of this bottom water northwards across the outer 1000 m shelf isobath. Overall flow complexity suggests care is needed to force regional Ross Sea models.
The continental margin of southern South Africa exhibits an array of emergent marginal marine sediments permitting the reconstruction of long-term eustatic sea-level changes. We report a suite of optical luminescence ages and supplementary amino acid racemization data, which provide paleosea-level index points for three sites on this coastline. Deposits in the Swartvlei and Groot Brak estuaries display tidal inlet facies overlain by shoreface or eolian facies. Contemporary facies relations suggest a probable high stand 6.0-8.5 m above modern sea level (amsl). At Cape Agulhas, evidence of a past sea-level high stand comprises a gravel beach (ca. 3.8 m amsl) and an overlying sandy shoreface facies (up to 7.5 m amsl). OSL ages between 138±7 ka and 118±7 ka confirm a last interglacial age for all marginal marine facies. The high stand was followed by a sea-level regression that was associated with the accumulation of eolian dunes dating to between 122±7 ka and 113±6 ka. These data provide the first rigorous numerical age constraints for last interglacial sea-level fluctuations in this region, revealing the timing and elevation of the last interglacial high stand to broadly mirror a number of other far-field locations.
We sought to assess the impact of the integration of the new roles of primary health care nurse practitioners (NPs) and physician assistants (PAs) on patient flow, wait times and proportions of patients who left without being seen in 6 Ontario emergency departments (EDs).
We performed a retrospective review of health records data on patient arrival time, time of initial assessment by a physician, time of discharge from the ED and discharge status.
Whether a PA or NP was directly involved in the care of patients or indirectly involved by being on duty, the wait times, lengths of stay and proportion of patients who left without being seen were significantly reduced. When a PA or NP were directly involved in patients' care, patients were 1.6 (95% confidence interval [CI] 1.3–2.1, p < 0.05) and 2.1 (95% CI 1.6–2.8, p < 0.05) times more likely to be seen within the wait time benchmarks, respectively. Lengths of stay were 30.3% (95% CI 21.6%–39.0%, p < 0.01) and 48.8% (95% CI 35.0%–62.7%, p < 0.01) lower when PAs and NPs, respectively, were involved. When PAs and NPs were not on duty, the proportion of patients who left without being seen were 44% (95% CI 31%–63%, p < 0.01) and 71% (95% CI 53%–96%, p < 0.05), respectively.
The addition of PAs or NPs to the ED team can improve patient flow in medium-sized community hospital EDs. Given the ongoing shortage of physicians, use of alternative health care providers should be considered. These results require validation, as their generalizability to other locations or types of EDs is not known.
Patients whose symptoms are ‘unexplained by disease’ often have a poor symptomatic outcome after specialist consultation, but we know little about which patient factors predict this. We therefore aimed to determine predictors of poor subjective outcome for new neurology out-patients with symptoms unexplained by disease 1 year after the initial consultation.
The Scottish Neurological Symptom Study was a 1-year prospective cohort study of patients referred to secondary care National Health Service neurology clinics in Scotland (UK). Patients were included if the neurologist rated their symptoms as ‘not at all’ or only ‘somewhat explained’ by organic disease. Patient-rated change in health was rated on a five-point Clinical Global Improvement (CGI) scale (‘much better’ to ‘much worse’) 1 year later.
The 12-month outcome data were available on 716 of 1144 patients (63%). Poor outcome on the CGI (‘unchanged’, ‘worse’ or ‘much worse’) was reported by 482 (67%) out of 716 patients. The only strong independent baseline predictors were patients' beliefs [expectation of non-recovery (odds ratio [OR] 2.04, 95% confidence interval [CI] 1.40–2.96), non-attribution of symptoms to psychological factors (OR 2.22, 95% CI 1.51–3.26)] and the receipt of illness-related financial benefits (OR 2.30, 95% CI 1.37–3.86). Together, these factors predicted 13% of the variance in outcome.
Of the patients, two-thirds had a poor outcome at 1 year. Illness beliefs and financial benefits are more useful in predicting poor outcome than the number of symptoms, disability and distress.
Corals are diaries that record within their pages many types of environmental information …
Geochemistry of corals: proxies of past ocean chemistry, ocean circulation, and climate Ellen R. M. Druffel (1997)
Viewed from space the oceans dominate the surface of the Earth – as Arthur C. Clarke once noted, ‘How inappropriate to call this planet Earth when it is quite clearly Ocean.’ In terms of climate, the oceans are the Earth's major heat storage and transport system. For example, the first three metres of the oceans alone have an equivalent heat capacity to the Earth's entire atmosphere. Ultimately it is the oceans that exert the strongest control over planetary climate change and so perhaps it is not surprising that the clues to past climate change and the symptoms of future climate change can be found in the ocean record. Palaeoceanographers have reconstructed past climatic conditions using marine temperature proxies recorded in diverse sources ranging from foraminiferal tests in deep-sea sediments to annually banded shallow-water tropical corals. For example, oxygen isotope records from shallow, warm-water corals have revealed a recent, long-term warming and/or freshening throughout tropical regions (see review by Grottoli & Eakin, 2007). As predicted by Druffel (1997), cold-water corals are now emerging as a key archive of intermediate water-mass history. Unlike sediment-based foraminiferal records, which can be disrupted by the sediment mixing activity of infauna (bioturbation), coral skeletons offer continuous, high-resolution archives. Unlike tropical corals they are not restricted to the shallow, euphotic zone at tropical latitudes.
Richly coralliferous biostromal and biohermal limestones are widely regarded as indicators of a clear, warm, shallow-water depositional environment. If in such rocks coral organisms are associated with a rich bryozoan, brachiopod, molluscan, and echinoderm fauna, this conclusion will by most geologists be considered to approach the certainty of an observational fact. … this conclusion is not necessarily valid.
Cold- and deep-water coral banks. Curt Teichert (1958)
This chapter brings a new dimension to the understanding of cold-water coral habitats by considering cold-water corals from the temporal perspective of the fossil record. We will focus on the calcified Scleractinia as their stony skeletons are widely preserved in ancient rocks. The early evolution and phylogeny of Scleractinia have been studied by comparing morphological characteristics of extant and extinct corals, their skeletal ultrastructure and, recently, by using molecular phylogenetics (see Section 2.5, p. 52). However, none of these approaches have so far provided a unified theory for the origin of the Scleractinia. The present-day coral reef ecosystem, both in shallow and deep waters, is a geologically young achievement and its fossil record is a fascinating story of extinctions and radiations mirroring dramatic changes in the Earth's climatic history. This chapter sheds light on the fossil record of the main habitat-forming cold-water coral genera Lophelia, Madrepora, Goniocorella, Oculina and Enallopsammia and it describes fossilisation processes that control the quality of preservation in this record.
What does the fossil record of the Scleractinia tell us about their ancestry?
To most people corals are synonymous with the bright, well-lit waters of tropical coral reefs. Yet in fact the majority of corals inhabit deep, cold waters across a diverse range of marine environments from inland fjords to the continental shelf, slope, offshore banks, seamounts and even the abyssal plain. While we have known about these cold-water corals for hundreds, or even thousands, of years it is only in the last ten years that research into the biology of the corals themselves, the ecology of the habitats they provide and the geology of the structures they form has gathered pace. Cold-water coral habitats are biodiversity rich. Recent work has revealed them as unique palaeoceanographic archives. Sadly all too many surveys have shown they have been damaged by human activity. In this book we have tried to summarise the many, varied and exciting developments in our understanding of cold-water corals. Research effort on cold-water corals is now increasing exponentially around the world and it has been challenging to compress this body of work into the pages of one book. Before we consider cold-water corals and some of these recent findings in more detail we begin with a brief historical summary and an outline of the research approaches used to study cold-water corals.
Early history and taxonomy
The history of modern research on cold-water corals goes back to the late eighteenth century.