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The neurobiological basis of neuroticism in late-life depression (LLD) is understudied. We hypothesized that older depressed subjects scoring high in measures of neuroticism would have smaller hippocampal and prefrontal volumes compared with non-neurotic older depressed subjects and with nondepressed comparison subjects based on previous research. Non-demented subjects were recruited and were either depressed with high neuroticism (n = 65), depressed with low neuroticism (n = 36), or never depressed (n = 27). For imaging outcomes focused on volumetric analyses, we found no significant between-group differences in hippocampal volume. However, we found several frontal lobe regions for which depressed subjects with high neuroticism scores had smaller volumes compared with non-neurotic older depressed subjects and with nondepressed comparison subjects, controlling for age and gender. These regions included the frontal pole, medial orbitofrontal cortex, and left pars orbitalis. In addition, we found that non-neurotic depressed subjects had a higher volume of non-white matter hypointensities on T1-weighted images (possibly related to cerebrovascular disease) than did neurotic depressed subjects. Our finding that depressed subjects low in neuroticism had higher volumes of non-white matter hypointensities is consistent with prior literature on “vascular depression.” In contrast, the finding that those high in neuroticism had smaller frontal volume than depressed subjects low in neuroticism and never-depressed subjects highlight the importance of frontal circuitry in the subgroup of older depressed individuals with comorbid neuroticism. Together, these results implicate different neural mechanisms in older neurotic and non-neurotic depressed groups and suggest that multiple biological pathologies may lead to different clinical expressions of LLD.
Arctic mining has a bad reputation because the extractive industry is often responsible for a suite of environmental problems. Yet, few studies explore the gap between untouched tundra and messy megaproject from a historical perspective. Our paper focuses on Advent City as a case study of the emergence of coal mining in Svalbard (Norway) coupled with the onset of mining-related environmental change. After short but intensive human activity (1904–1908), the ecosystem had a century to respond, and we observe a lasting impact on the flora in particular. With interdisciplinary contributions from historical archaeology, archaeozoology, archaeobotany and botany, supplemented by stable isotope analysis, we examine 1) which human activities initially asserted pressure on the Arctic environment, 2) whether the miners at Advent City were “eco-conscious,” for example whether they showed concern for the environment and 3) how the local ecosystem reacted after mine closure and site abandonment. Among the remains of typical mining infrastructure, we prioritised localities that revealed the subtleties of long-term anthropogenic impact. Significant pressure resulted from landscape modifications, the import of non-native animals and plants, hunting and fowling, and the indiscriminate disposal of waste material. Where it was possible to identify individual inhabitants, these shared an economic attitude of waste not, want not, but they did not hold the environment in high regard. Ground clearances, animal dung and waste dumps continue to have an effect after a hundred years. The anthropogenic interference with the fell field led to habitat creation, especially for vascular plants. The vegetation cover and biodiversity were high, but we recorded no exotic or threatened plant species. Impacted localities generally showed a reduction of the natural patchiness of plant communities, and highly eutrophic conditions were unsuitable for liverworts and lichens. Supplementary isotopic analysis of animal bones added data to the marine reservoir offset in Svalbard underlining the far-reaching potential of our multi-proxy approach. We conclude that although damaging human–environment interactions formerly took place at Advent City, these were limited and primarily left the visual impact of the ruins. The fell field is such a dynamic area that the subtle anthropogenic effects on the local tundra may soon be lost. The fauna and flora may not recover to what they were before the miners arrived, but they will continue to respond to new post-industrial circumstances.
Sink drains in healthcare facilities may provide an environment for antimicrobial-resistant microorganisms, including carbapenemase-producing Klebsiella pneumoniae (CPKP).
We investigated the colonization of a biofilm consortia by CPKP in a model system simulating a sink-drain P-trap. Centers for Disease Control (CDC) biofilm reactors (CBRs) were inoculated with microbial consortia originally recovered from 2 P-traps collected from separate patient rooms (designated rooms A and B) in a hospital. Biofilms were grown on stainless steel (SS) or polyvinyl chloride (PVC) coupons in autoclaved municipal drinking water (ATW) for 7 or 28 days.
Microbial communities in model systems (designated CBR-A or CBR-B) were less diverse than communities in respective P-traps A and B, and they were primarily composed of β and γ Proteobacteria, as determined using 16S rRNA community analysis. Following biofilm development CBRs were inoculated with either K. pneumoniae ST45 (ie, strain CAV1016) or K. pneumoniae ST258 KPC+ (ie, strain 258), and samples were collected over 21 days. Under most conditions tested (CBR-A: SS, 7-day biofilm; CBR-A: PVC, 28-day biofilm; CBR-B: SS, 7-day and 28-day biofilm; CBR-B: PVC, 28-day biofilm) significantly higher numbers of CAV1016 were observed compared to 258. CAV1016 showed no significant difference in quantity or persistence based on biofilm age (7 days vs 28 days) or substratum type (SS vs PVC). However, counts of 258 were significantly higher on 28-day biofilms and on SS.
These results suggest that CPKP persistence in P-trap biofilms may be strain specific or may be related to the type of P-trap material or age of the biofilm.
Understanding risk factors for death from Covid-19 is key to providing good quality clinical care. We assessed the presenting characteristics of the ‘first wave’ of patients with Covid-19 at Royal Oldham Hospital, UK and undertook logistic regression modelling to investigate factors associated with death. Of 470 patients admitted, 169 (36%) died. The median age was 71 years (interquartile range 57–82), and 255 (54.3%) were men. The most common comorbidities were hypertension (n = 218, 46.4%), diabetes (n = 143, 30.4%) and chronic neurological disease (n = 123, 26.1%). The most frequent complications were acute kidney injury (AKI) (n = 157, 33.4%) and myocardial injury (n = 21, 4.5%). Forty-three (9.1%) patients required intubation and ventilation, and 39 (8.3%) received non-invasive ventilation. Independent risk factors for death were increasing age (odds ratio (OR) per 10 year increase above 40 years 1.87, 95% confidence interval (CI) 1.57–2.27), hypertension (OR 1.72, 95% CI 1.10–2.70), cancer (OR 2.20, 95% CI 1.27–3.81), platelets <150 × 103/μl (OR 1.93, 95% CI 1.13–3.30), C-reactive protein ≥100 μg/ml (OR 1.68, 95% CI 1.05–2.68), >50% chest radiograph infiltrates (OR 2.09, 95% CI 1.16–3.77) and AKI (OR 2.60, 95% CI 1.64–4.13). There was no independent association between death and gender, ethnicity, deprivation level, fever, SpO2/FiO2, lymphopoenia or other comorbidities. These findings will inform clinical and shared decision making, including use of respiratory support and therapeutic agents.
Radiocarbon (14C) ages cannot provide absolutely dated chronologies for archaeological or paleoenvironmental studies directly but must be converted to calendar age equivalents using a calibration curve compensating for fluctuations in atmospheric 14C concentration. Although calibration curves are constructed from independently dated archives, they invariably require revision as new data become available and our understanding of the Earth system improves. In this volume the international 14C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP. Based on tree rings, IntCal20 now extends as a fully atmospheric record to ca. 13,900 cal BP. For the older part of the timescale, IntCal20 comprises statistically integrated evidence from floating tree-ring chronologies, lacustrine and marine sediments, speleothems, and corals. We utilized improved evaluation of the timescales and location variable 14C offsets from the atmosphere (reservoir age, dead carbon fraction) for each dataset. New statistical methods have refined the structure of the calibration curves while maintaining a robust treatment of uncertainties in the 14C ages, the calendar ages and other corrections. The inclusion of modeled marine reservoir ages derived from a three-dimensional ocean circulation model has allowed us to apply more appropriate reservoir corrections to the marine 14C data rather than the previous use of constant regional offsets from the atmosphere. Here we provide an overview of the new and revised datasets and the associated methods used for the construction of the IntCal20 curve and explore potential regional offsets for tree-ring data. We discuss the main differences with respect to the previous calibration curve, IntCal13, and some of the implications for archaeology and geosciences ranging from the recent past to the time of the extinction of the Neanderthals.
Reradiative or greenhouse gases were reviewed in Chapter 2. Elevated carbon dioxide is considered to be the most persistent cause of global warming and climate change, having greatly exceeded the capacity of natural terrestrial and ocean sinks. Carbon dioxide is the bridge or link between the land and ocean sinks (Box 3.1). Previously these sinks functioned to keep carbon dioxide in the air at levels that did not result in appreciable global warming. Carbon moves in the environment in slow, intermediate, and relatively fast cycles. Understanding the nature of these cycles will enhance understanding of the important role of carbon and carbon dioxide in the environment.
There is considerable interest and concern about global warming and climate change. In response, there is also great interest in the role that tree planting and new forests might play in partial mitigation of global warming and in reducing climate change by cooling the atmosphere now and especially in the future, as carbon dioxide increases. This interest is evident in the very large number of reports and conclusions in widely diverse scientific journals, books, and the popular media. The purpose of this book is to bring together in one place a review of background information and results from sources, primarily reports in scientific journals, about global warming and the role of forests in cooling and warming the atmosphere now and in future projections.
This chapter provides a review of interactive forest-related factors that influence the temperature of the atmosphere. Factors revisited and expanded from previous chapters include carbon dioxide, carbon accumulation, deforestation and afforestation, evaporation and transpiration, albedo, BVOCs, and ozone (Bonan, 2008; Mackey et al., 2013; Unger, 2014; Ellison et al., 2017). Occurring together, and influenced by many other factors, they constitute the system by which forests cool or warm the atmosphere.
In Chapter 4, interactive biogeochemical and biophysical factors that affect tree function in relation to atmospheric cooling and warming were considered. Biogeochemical factors include photosynthesis and biogenic hydrocarbons. Biophysical factors include albedo, evapotranspiration, and ozone. How growth, photosynthesis, transpiration, and ozone affect trees due to increasing changes in atmospheric temperature and composition will be considered here.
Previous chapters considered the nature and cause of global warming; the key role of carbon dioxide; the importance of the biogeochemical factors photosynthesis and BVOCs, and the biogeophysical factors albedo, evapotranspiration, and ozone; and how their interactions affect forests, atmospheric temperatures, and climate. Warming temperatures, forest fires, insect infestations, drought, deforestation and land-use change, latitudinal forest locations, and species composition all affect these interactions.
Global deforestation is increasing rapidly from timber harvesting, charcoal burning, fires, beetle infestations, drought, disturbances, and conversion of forests to managed land for agriculture and pasture. This reduces the global carbon sink and may increase global temperature. It was noted in the previous chapter, however, that observed average global temperatures and carbon dioxide concentrations are lower than would be expected from model estimates. This was attributed to a long-term global vegetation growth and greening effect, caused by increased photosynthesis and increased transpiration. Forest trees probably constitute most of the vegetation responsible. The potential for global greening has greatly increased interest in global large-scale efforts to prevent deforestation, stop forest degradation, restore forests (reforestation), plant new forests (afforestation), and manage existing forests.
To assess the effects of trees and forests on the temperature of the atmosphere, it is essential to review how they function in relation to biogeochemical factors, such as photosynthesis and release of biogenic hydrocarbons (BVOCs), and biophysical factors, such as albedo, deforestation, and land-use change, evapotranspiration, and ozone. Although biogeochemical and biophysical factors can be considered separately, their interactive roles determine whether trees and forests cool or warm the atmosphere.
In the previous chapter, environmental and biological factors that affect tree and forest health, vitality, growth, carbon sequestration, and survival were considered. How different types of forests respond to interactions of these factors depends on their composition and location. The nature of the world’s natural and urban forests affects their function and role in carbon sequestration and in atmospheric cooling and warming. It seems appropriate to consider the nature, composition, function, and future of the forests of the world.
Large-scale tree planting is advocated to provide additional atmospheric cooling and further reduce global warming. This raises a question about the present time: do trees cool or warm the atmosphere? This question does not have a simple yes or no answer. Examination of the greenhouse effect, global warming and the carbon cycle, and how trees and forests function provides the basis for understanding how forests might cool or warm the atmosphere. Results from research and models indicate that cooling or warming depends on where forests are located and the type and color of trees. Cooling generally prevails over warming, but this may change. This book will appeal to anyone interested in climate change, ecology and conservation.