Basaltic sands cover several plains in volcanic regions on Earth and dominate the aeolian sediments on Mars but basaltic sands are not as well characterized as felsic sands. The Lambahraun sandy–lava ...plain in Iceland was chosen as a martian analog to study the physical sorting of basaltic sands. The strong winds affecting the plain and its young age (<
4000
yr) have preserved unaltered sand grains. Sands displayed subtle differences in bulk chemical composition from the basaltic source rocks suggesting that mineral abundances are modified by the aeolian transport. A paired enrichment in Mg and Ni in sands relative to the source rock is observed and results from a higher proportion of olivine grains in sand. This enrichment is variable among sand samples and is correlated with the decrease of the mean grain size of sand; a value related to the degree of aeolian sorting. This enrichment is explained by the presence of well-developed olivine minerals (100 to 500
μm in length) in the source rocks, olivine hardness and density, and the removal of plagioclases. As olivine has been detected by spectral data in several sand dunes on Mars, these results have important implications for martian studies. It shows that olivine abundances deduced from spectral data on martian sand dunes could overestimate that of the source rocks, whereas the presence of a few percents of olivine in the rocks can cause olivine enrichment by aeolian processes. In general, our results show that mineral segregation in basaltic sands should be considered when mineralogical and chemical data of the Mars surface are interpreted.
► Basaltic sands are affected by aeolian segregation producing olivine-enrichment. ► Olivine enrichment is revealed by paired enrichment in Mg and Ni. ► Olivine enrichment is anti-correlated with the mean grain size. ► Olivine enrichment in basaltic sands should be considered for Mars data.
We report constraints on nonstandard neutrino interactions (NSI) from the observation of atmospheric neutrinos with IceCube, limiting all individual coupling strengths from a single dataset. ...Furthermore, IceCube is the first experiment to constrain flavor-violating and nonuniversal couplings simultaneously. Hypothetical NSI are generically expected to arise due to the exchange of a new heavy mediator particle. Neutrinos propagating in matter scatter off fermions in the forward direction with negligible momentum transfer. Hence the study of the matter effect on neutrinos propagating in the Earth is sensitive to NSI independently of the energy scale of new physics. We present constraints on NSI obtained with an all-flavor event sample of atmospheric neutrinos based on three years of IceCube DeepCore data. The analysis uses neutrinos arriving from all directions, with reconstructed energies between 5.6 GeV and 100 GeV. We report constraints on the individual NSI coupling strengths considered singly, allowing for complex phases in the case of flavor-violating couplings. This demonstrates that IceCube is sensitive to the full NSI flavor structure at a level competitive with limits from the global analysis of all other experiments. In addition, we investigate a generalized matter potential, whose overall scale and flavor structure are also constrained.
Experiments were conducted with polymyxin B and two
isogenic strains (the wild type, KP_WT, and its transconjugant carrying the mobile colistin resistance gene, KP_MCR-1) to demonstrate that ...conducting two consecutive time-kill experiments (sequential TK) represents a simple approach to discriminate between pharmacokinetics/pharmacodynamics models with two heterogeneous subpopulations or adaptive resistance.
Maternal immune activation (MIA) and poor maternal nutritional habits are risk factors for the occurrence of neurodevelopmental disorders (NDD). Human studies show the deleterious impact of prenatal ...inflammation and low n-3 polyunsaturated fatty acid (PUFA) intake on neurodevelopment with long-lasting consequences on behavior. However, the mechanisms linking maternal nutritional status to MIA are still unclear, despite their relevance to the etiology of NDD. We demonstrate here that low maternal n-3 PUFA intake worsens MIA-induced early gut dysfunction, including modification of gut microbiota composition and higher local inflammatory reactivity. These deficits correlate with alterations of microglia-neuron crosstalk pathways and have long-lasting effects, both at transcriptional and behavioral levels. This work highlights the perinatal period as a critical time window, especially regarding the role of the gut-brain axis in neurodevelopment, elucidating the link between MIA, poor nutritional habits, and NDD.
We compare five global inventories of monthly CO emissions named VGT, ATSR, MODIS, GFED3 and MOPITT based on remotely sensed active fires and/or burned area products for the year 2003. The objective ...is to highlight similarities and differences by focusing on the geographical and temporal distribution and on the emissions for three broad land cover classes (forest, savanna/grassland and agriculture). Globally, CO emissions for the year 2003 range between 365 Tg CO (GFED3) and 1422 Tg CO (VGT). Despite the large uncertainty in the total amounts, some common spatial patterns typical of biomass burning can be identified in the boreal forests of Siberia, in agricultural areas of Eastern Europe and Russia and in savanna ecosystems of South America, Africa and Australia. Regionally, the largest difference in terms of total amounts (CV > 100%) and seasonality is observed at the northernmost latitudes, especially in North America and Siberia where VGT appears to overestimate the area affected by fires. On the contrary, Africa shows the best agreement both in terms of total annual amounts (CV = 31%) and of seasonality despite some overestimation of emissions from forest and agriculture observed in the MODIS inventory. In Africa VGT provides the most reliable seasonality. Looking at the broad land cover types, the range of contribution to the global emissions of CO is 64–74%, 23–32% and 3–4% for forest, savanna/grassland and agriculture, respectively. These results suggest that there is still large uncertainty in global estimates of emissions and it increases if the comparison is carried by out taking into account the temporal (month) and spatial (0.5° × 0.5° cell) dimensions. Besides the area affected by fires, also vegetation characteristics and conditions at the time of burning should also be accurately parameterized since they can greatly influence the global estimates of CO emissions.
We present a measurement of the density of GeV muons in near-vertical air showers using three years of data recorded by the IceTop array at the South Pole. Depending on the shower size, the muon ...densities have been measured at lateral distances between 200 and 1000 m. From these lateral distributions, we derive the muon densities as functions of energy at reference distances of 600 and 800 m for primary energies between 2.5 and 40 PeV and between 9 and 120 PeV, respectively. The muon densities are determined using, as a baseline, the hadronic interaction model Sibyll 2.1 together with various composition models. The measurements are consistent with the predicted muon densities within these baseline interaction and composition models. The measured muon densities have also been compared to simulations using the postLHC models EPOS-LHC and QGSJet-II.04. The result of this comparison is that the post-LHC models together with any given composition model yield higher muon densities than observed. This is in contrast to the observations above 1 EeV where all model simulations yield for any mass composition lower muon densities than the measured ones. The post-LHC models in general feature higher muon densities so that the agreement with experimental data at the highest energies is improved but the muon densities are not correct in the energy range between 2.5 and about 100 PeV.
Antipsychotic polypharmacy and high doses have been associated with poorer outcome, longer hospital stays, and increased side effects. The present naturalistic study assessed the cognitive effects of ...antipsychotics in 56 patients with a diagnosis of schizophrenia or schizoaffective disorder, using the Brief Assessment of Cognition in Schizophrenia (BACS). Antipsychotic daily dose (ADD) was expressed as mg risperidone equivalents/day (RIS eq), using a model based on drug doses from the Clinical Antipsychotic Trials in Intervention Effectiveness (CATIE) study for second generation antipsychotics (SGA) and chlorpromazine equivalents for first generation antipsychotics (FGA), with a 1/1 equivalence between haloperidol and risperidone. Increasing age was associated with polypharmacy, FGA prescription and decreasing BACS score. FGA prescription, in turn, predicted a poorer cognitive functioning, independently of age, PANSS subscores and ADD. ADD was associated with decreasing cognitive scores, an effect that remained significant after controlling for age, PANSS or polypharmacy. The detrimental cognitive effects of polypharmacy, in turn, appeared to be mediated by ADD. Different methods of data fitting suggested that ADD above 5—6 mg RIS eq/day were associated with lower BACS scores. Overall, these results show that increasing antipsychotic daily dose is associated with poorer cognitive functioning at doses lower than previously thought, independently of the number of antipsychotic drugs.
Climate warming is shifting the distributions of mountain plant species to higher elevations. Cold‐adapted plant species are under increasing pressure from novel competitors that are encroaching from ...lower elevations. Plant capacity to adjust to these pressures may be measurable as variation in trait values within a species. In particular, the strength and patterns of intraspecific trait variation along abiotic and biotic gradients can inform us whether and how species can adjust their anatomy and morphology to persist in a changing environment.
Here, we tested whether species specialized to high elevations or with narrow elevational ranges show more conservative (i.e. less variable) trait responses across their elevational distribution, or in response to neighbours, than species from lower elevations or with wider elevational ranges. We did so by studying intraspecific trait variation of 66 species along 40 elevational gradients in four countries in both hemispheres. As an indication of potential neighbour interactions that could drive trait variation, we also analysed plant species’ height ratio, its height relative to its nearest neighbour.
Variation in alpine plant trait values over elevation differed depending on a species’ median elevation and the breadth of its elevational range, with species with lower median elevations and larger elevational range sizes showing greater trait variation, i.e. a steeper slope in trait values, over their elevational distributions. These effects were evidenced by significant interactions between species’ elevation and their elevational preference or range for several traits: vegetative height, generative height, specific leaf area and patch area. The height ratio of focal alpine species and their neighbours decreased in the lower part of their distribution because neighbours became relatively taller at lower elevations. In contrast, species with lower elevational optima maintained a similar height ratio with neighbours throughout their range.
Synthesis. We provide evidence that species from lower elevations and those with larger range sizes show greater intraspecific trait variation, which may indicate a greater ability to respond to environmental changes. Also, larger trait variation of species from lower elevations may indicate stronger competitive ability of upslope shifting species, posing one further threat to species from higher ranges.
Zusammenfassung
Durch die Klimaerwärmung breiten sich Pflanzen in grösseren Höhen aus. Kälte‐adaptierte Gebirgspflanzen sind daher unter erhöhtem Konkurrenzdruck durch Arten aus niedrigeren Höhenstufen. Die Fähigkeit einer Pflanzenart auf Konkurrenzdruck zu reagieren, könnte messbar sein als deren Variation von Traits (Merkmalen). Besonders die Muster von intraspezifischer Variation von Traits entlang abiotischer und biotischer Gradienten kann anzeigen, ob und wie Arten ihre Anatomie und Morphologie verändern, um sich in einer sich ändernden Umwelt zu behaupten.
In dieser Studie testen wir, ob Hochgebirgs‐Arten oder solche mit einem engen Verbreitungsgebiet entlang eines topografischen Höhengradienten konservativer (d.h. weniger variabel) entlang ihrer Höhenverbreitung oder in Bezug auf Nachbararten sind als Arten aus geringeren Höhen oder mit einer grösseren Höhenverbreitung. Wir untersuchten intraspezifische Trait‐Variation von 66 Arten entlang von 40 Höhengradienten in 4 Ländern der Nord‐ und Südhemisphäre. Als Hinweis auf mögliche Interaktionen unserer Zielarten mit Nachbararten, die für Trait‐Variation verantwortlich sein könnten, analysierten wir zusätzlich die Pflanzenwuchshöhe relativ zu derjenigen der nächsten Nachbarpflanze.
Die Variation von Pflanzeneigenschaften über den topographischen Höhengradienten hing ab vom Median und der Grösse der Höhenverbreitung einer Art. Arten aus niedrigeren Höhenlagen und mit grösserer Höhenverbreitung zeigten grössere Variation, d.h. eine stärkere Veränderung von Traits über den Höhengradienten. Diese Effekte zeigten sich in signifikanten Interaktionen zwischen Meereshöhe und Höhenverbreitung bzw. Grösse der Höhenverbreitung für verschiedene Traits: Vegetative und generative Pflanzenhöhe, spezifische Blattfläche und Fläche einer Pflanze.
Das Verhältnis der Pflanzenwuchshöhe von Arten mit spezifisch hochalpiner Verbreitung mit ihren Nachbarn verringerte sich mit geringerer Meereshöhe, da die Nachbarn dort relativ grösser wurden. Im Gegensatz dazu blieben Arten mit tieferliegenden Verbreitungen ähnlich gross wie ihre Nachbarn über den gesamten topografischen Höhengradienten hinweg.
Synthese. Unsere Studie zeigt, dass Arten aus tieferen Lagen und mit grösserer Höhenverbreitung grössere intraspezifische Trait‐Variation zeigen, was ein Hinweis darauf sein könnte, dass sie besser auf Umweltveränderungen reagieren können. Grössere Trait‐Variation von Arten aus niedrigeren Höhenlagen kann ausserdem bedeuten, dass sie konkurrenzstärker sind, was eine Bedrohung für hochalpine Spezialisten bedeuten kann.
Plant species (☆) from lower elevations and those with larger range sizes (pale diamonds) show greater intraspecific trait variation (e.g. plant height, right panel), which may indicate a greater ability to respond to environmental changes. Also, larger trait variation of species from lower elevations may indicate stronger competitive ability of upslope shifting species, posing one further threat to species from higher ranges.
Lutein and zeaxanthin may lower the risk of age-related macular degeneration (AMD). We evaluated the associations of plasma lutein and zeaxanthin with the incidence of advanced AMD in the Alienor ...study (Antioxydants Lipides Essentiels Nutrition et Maladies Oculaires). Alienor study is a prospective population-based cohort of 963 residents of Bordeaux, France, who were 73 years or older at baseline (2006–2008). The present study included 609 participants with complete ophthalmologic and plasma carotenoids data. Examinations were performed every two years over an eight-year period (2006 to 2017). Plasma lutein and zeaxanthin were determined at baseline from fasting blood samples using high-performance liquid chromatography. Cox proportional hazard models were used to assess associations between plasma lutein, zeaxanthin, and their (total cholesterol (TC) + triglycerides (TG)) ratios with AMD. Among the 609 included participants, 54 developed advanced incident AMD during a median follow-up time of 7.6 years (range 0.7 to 10.4). Participants with higher plasma lutein had a reduced risk for incident advanced AMD in the fully adjusted model (HR = 0.63 per 1-SD increase (95% CI, 0.41–0.97), p = 0.03). A similar association was observed using the lutein/(TC + TG) ratio (HR = 0.59 (95% CI, 0.39–0.90), p = 0.01). No associations were evidenced for other carotenoids. Higher plasma lutein was associated with a 37% reduced risk of incident advanced AMD.
Abstract Purpose The objective of this project was to define consensus guidelines for delineating organs at risk (OARs) for head and neck radiotherapy for routine daily practice and for research ...purposes. Methods Consensus guidelines were formulated based on in-depth discussions of a panel of European, North American, Asian and Australian radiation oncologists. Results Twenty-five OARs in the head and neck region were defined with a concise description of their main anatomic boundaries. The Supplemental material provides an atlas of the consensus guidelines, projected on 1 mm axial slices. The atlas can also be obtained in DICOM-RT format on request. Conclusion Consensus guidelines for head and neck OAR delineation were defined, aiming to decrease interobserver variability among clinicians and radiotherapy centers.
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