Abiotic release of nitrous acid (HONO) in equilibrium with soil nitrite (NO 2 - ) was suggested as an important contributor to the missing source of atmospheric HONO and hydroxyl radicals (OH). The ...role of total soil-derived HONO in the biogeochemical and atmospheric nitrogen cycles, however, has remained unknown. In laboratory experiments, we found that for nonacidic soils from arid and arable areas, reactive nitrogen emitted as HONO is comparable with emissions of nitric oxide (NO). We show that ammonia-oxidizing bacteria can directly release HONO in quantities larger than expected from the acid-base and Henry's law equilibria of the aqueous phase in soil. This component of the nitrogen cycle constitutes an additional loss term for fixed nitrogen in soils and a source for reactive nitrogen in the atmosphere.
Summary
Exosomes in plasma of head and neck squamous cell carcinoma (HNSCC) patients comprise subsets of vesicles derived from various cells. Recently, we separated CD3(+) from CD3(–) exosomes by ...immune capture. CD3(–) exosomes were largely tumour‐derived (CD44v3+). Both subsets carried immunosuppressive proteins and inhibited functions of human immune cells. The role of these subsets in immune cell reprogramming by the tumour was investigated by focusing on the adenosine pathway components. Spontaneous adenosine production by CD3(+) or CD3(–) exosomes was measured by mass spectrometry, as was the production of adenosine by CD4+CD39+ regulatory T cells (Treg) co‐incubated with these exosomes. The highest level of CD39/CD73 ectoenzymes and of adenosine production was found in CD3(–) exosomes in patients with the stages III/IV HNSCCs). Also, the production of 5′‐AMP and purines was significantly higher in Treg co‐incubated with CD3(–) than CD3(+) exosomes. Consistently, CD26 and adenosine deaminase (ADA) levels were higher in CD3(+) than CD3(–) exosomes. ADA and CD26 levels in CD3(+) exosomes were significantly higher in patients with early (stages I/II) than advanced (stages III/IV) disease. HNSCC patients receiving and responding to photodynamic therapy had increased ADA levels in CD3(+) exosomes with no increase in CD3(–) exosomes. The opposite roles of CD3(+) ADA+CD26+ and CD3(–)CD44v3+ adenosine‐producing exosomes in early versus advanced HNSCC suggest that, like their parent cells, these exosomes serve as surrogates of immune suppression in cancer.
Separation of plasma‐derived exosomes in a CD3 (+) T cell derived exosome fraction and a CD3 (−) fraction enriched in tumor derived exosomes have the potential to serve as biomarkers of tumor activities and also as biomarkers of immune competence/suppression.
To systematically review clinicians' knowledge and beliefs about the importance and causes of antibiotic resistance, and strategies to reduce resistance.
Four databases were searched (until July ...2014), without restrictions on language, setting or study design. Fixed responses (from surveys) were grouped into categories. The proportion of participants who agreed with each category was expressed as median, percentage and IQR. Qualitative data were coded into emergent themes. Quantitative categories and qualitative themes were grouped into four overarching categories that emerged from the data.
There were 57 included studies (38 quantitative, 14 qualitative, 5 mixed methods) of 11593 clinicians. Most clinicians (69%, IQR 63%-72%, n=5 studies) had heard of antibiotic resistance and 98% (IQR 93%-99%, n=5 studies) believed it was serious. The proportion who believed it was a problem for their practice (67%, IQR 65%-74%, n=13 studies) was smaller than the proportion who believed it was a problem globally (89%, IQR 85%-97%, n=5 studies) or nationally (92%, IQR 88%-95%, n=21 studies). Most believed excessive antibiotic use (97%, IQR 91%-98%, n=12 studies) and patient non-adherence (90%, IQR 82%-92%, n=7 studies) caused resistance. Most knew of strategies to reduce resistance (e.g. clinician education, 90%, IQR 85%-96%, n=7 studies). Qualitative findings support these data: they attributed responsibility for antibiotic resistance to patients, other countries and healthcare settings; resistance was considered a low priority and a distant consequence of antibiotic prescribing.
Clinicians believe antibiotic resistance is a serious problem, but think it is caused by others. This needs to be accommodated in interventions to reduce antibiotic resistance.
In this article we present a unique, detailed, basin-wide, morphological analysis of the Rhine, one of the world's larger rivers. The objectives of this study were to characterize the basin-scale ...morphodynamics of the Rhine River in the period 1991–2010 by quantifying the downstream fluxes of clay, silt, sand, gravel and cobbles from source to mouth and identifying the sources and sinks of these sediments using sediment budget analyses. From source to mouth, the Rhine traverses four sections with fundamentally different morphodynamic behaviour: the Alpine, impounded, free-flowing and delta section. Sediment fluxes are discontinuous, primarily because of the presence of a glacial lake trapping all sediments from upstream. The lake caused sediment fluxes to be discontinuous already before the Anthropocene. Today's sediment fluxes are strongly influenced by dredging and nourishment operations. From a global perspective, sediment fluxes in the river's headwaters are large, whereas sediment output from the Rhine towards the sea is small. A special feature of the Rhine is the fact that more sediment is transported in upstream direction from the sea into the delta than vice versa. On a basin-scale, nourishment represents the biggest source of gravel and cobbles, and tributaries the biggest source of clay, silt and sand. In the lower Rhine delta, additional large amounts of clay, silt and sand are supplied by the sea. Dredging represents a main sediment sink for all size fractions. For silt and clay, also floodplain deposition and deposition in ports represent major sinks. The Rhine is a typical example of a river in disequilibrium: large parts of the river are subject to erosion or sedimentation. In contrast to other rivers with erosion upstream and deposition downstream, the Rhine has net deposition upstream and net erosion downstream. Although human interventions contributed to the disequilibrium, the pristine Rhine already was in a state of disequilibrium. Even today, natural factors determine the location of the main sedimentation areas. The budget analysis shows that the behaviour of the clay/silt, sand and gravel/cobble fractions strongly differ from each other. A particularity is that in many reaches gravel is deposited, whereas simultaneously sand is being eroded. The budget analysis also shows that sediment dynamics in rivers are much higher than is suggested by echosoundings or transport measurements. This study provides valuable insights into the basin-scale morphodynamics of the Rhine, helps to see smaller-scale studies of parts of the Rhine Basin in a correct perspective, provides a good data basis to improve numerical prediction models, and helps to optimize nourishment, dredging and monitoring strategies in the Rhine. Furthermore, the Rhine represents an excellent reference case for other large river systems for which less data are available. Knowledge gaps of supra-regional importance identified in this study relate to (A) the fundamental disequilibrium of large river systems, (B) the effect of natural and human factors on the future morphodynamic development of the large river systems, (C) the morphodynamic role of sand in gravel-bed rivers and (D) the long-term effects of sediment nourishment.
The efficacy of deep brain stimulation in treating movement disorders depends critically on electrode localization, which is conventionally described by using coordinates relative to the ...midcommissural point. This approach requires manual measurement and lacks spatial normalization of anatomic variances. Normalization is based on intersubject spatial alignment (coregistration) of corresponding brain structures by using different geometric transformations. Here, we have devised and evaluated a scheme for automated subcortical optimization of coregistration (ASOC), which maximizes patient-to-atlas normalization accuracy of postoperative structural MR imaging into the standard Montreal Neurologic Institute (MNI) space for the basal ganglia.
Postoperative T2-weighted MR imaging data from 39 patients with Parkinson disease and 32 patients with dystonia were globally normalized, representing the standard registration (control). The global transformations were regionally refined by 2 successive linear registration stages (RSs) (ASOC-1 and 2), focusing progressively on the basal ganglia with 2 anatomically selective brain masks, which specify the reference volume (weighted cost function). Accuracy of the RSs was quantified by spatial dispersion of 16 anatomic landmarks and their root-mean-square errors (RMSEs) with respect to predefined MNI-based reference points. The effects of CSF volume, age, and sex on RMSEs were calculated.
Mean RMSEs differed significantly (P < .001) between the global control (4.2 +/- 2.0 mm), ASOC-1 (1.92 +/- 1.02 mm), and ASOC-2 (1.29 +/- 0.78 mm).
The present method improves the registration accuracy of postoperative structural MR imaging data into MNI space within the basal ganglia, allowing automated normalization with increased precision at stereotactic targets, and enables lead-contact localization in MNI coordinates for quantitative group analysis.
Two novel bipolar host materials BPTRZ and MBPTRZ were synthesized, in which the hole transporting carbazole is separated from the electron transporting triazine moiety by a fully aromatic, but ...nonconjugated meta-linked biphenyl unit. The additional twist at the biphenyl in MBPTRZ, which is achieved by methyl-substitution in 2- and 2′-position of the biphenyl leads to a higher triplet energy of 2.81 eV compared to 2.70 eV for BPTRZ. Both materials possess high thermal stabilities and good glass forming properties. An organic light emitting diode with MBPTRZ as host for the blue phosphorescence emitter FIrpic shows a maximum luminance of 30600 cd/m2 and a maximum external quantum efficiency of 7.0%.
Mountain environments represent heterogeneous environments with shallow soils that are sensitive to human impact and climate change. Despite the thin soil cover, high soil organic carbon content of ...mountain soils may provide a major source of atmospheric CO2, if released. However, the importance of mountain soils remains controversial, largely due to insufficient information on the spatial variability of mountain SOC stocks. Here, we study the spatial variability of soil properties and SOC stocks in a changing mountain environment in the Bernese Alps (Switzerland) and the methodologies to assess them. We use different interpolation techniques (averaging, inverse distance, ordinary-, block- and regression-kriging) and sampling densities and analyze the sources of uncertainty using a nested sampling approach and the Gaussian and Taylor error propagation.
We found a low sensitivity of the median SOC stocks of the study area (ranging between 8.1 and 8.6kgCm−2 in the upper 30cm), the general patterns of the predicted stocks and the explanatory power with respect to the utilized interpolation techniques. In contrast the small-scale SOC pattern fluctuates strongly between different interpolation techniques. All interpolation techniques, except regression kriging, show a low variability of the calculated root mean square errors of the predicted SOC stocks in terms of variable sampling densities. To improve spatial prediction using regression kriging, which combines the kriging approach with multiple linear regression based on factors controlling the SOC variability (e.g. soil type, land use and topography), large sampling density (>35 samples per km2) is required in alpine environments. This is especially true for the coarse mineral fraction, which introduces the largest source of uncertainty. Nested sampling designs seem to provide an efficient tool to study SOC inventories and their associated sources of uncertainties in mountain environments.
•SOC inventories in alpine environments are characterized by large uncertainty.•Nested sampling allows estimation of spatial uncertainty of SOC inventories.•Analytical uncertainty is smaller than uncertainty related to spatial variability.•Uncertainty related to vertical variability is smaller than horizontal uncertainty.
In an increasingly human- and road-dominated world, the preservation of functional ecosystems has become highly relevant. While the negative ecological impacts of roads on ecosystems are numerous and ...well documented, roadless areas have been proposed as proxy for functional ecosystems. However, their potential remains underexplored, partly due to the incomplete mapping of roads. We assessed the accuracy of roadless areas identification using freely available road-data in two regions with contrasting levels of anthropogenic influence: boreal Canada and temperate Central Europe (Poland, Slovakia, Czechia, and Hungary). Within randomly selected circular plots (per region and country), we visually examined the completeness of road mapping using OpenStreetMap 2020 and assessed whether human influences affect mapping quality using four variables. In boreal Canada, roads were completely mapped in 3% of the plots, compared to 40% in Central Europe. Lower Human Footprint Index and road density values were related to greater incompleteness in road mapping. Roadless areas, defined as areas at least 1 km away from any road, covered 85% of the surface in boreal Canada (mean size ± s.d. = 272 ± 12,197 km
), compared to only 0.4% in temperate Central Europe (mean size ± s.d. = 0.6 ± 3.1 km
). By visually interpreting and manually adding unmapped roads in 30 randomly selected roadless areas from each study country, we observed a similar reduction in roadless surface in both Canada and Central Europe (27% vs 28%) when all roads were included. This study highlights the urgent need for improved road mapping techniques to support research on roadless areas as conservation targets and surrogates of functional ecosystems.
Particle coating experiments were performed in a lab-scale fluidized bed with varying process parameters, such as spraying rate and air inlet temperature, leading to different drying conditions. ...Porous (γ-Al2O3) and non-porous (glass) initial particles were sprayed with a sodium benzoate solution. For each experiment, the particle size distribution as well as the layer porosity was measured. The results show a dependency of the layer porosity on the drying conditions, represented by the drying potential of the fluidization gas. The obtained relationship is expressed as a linear correlation, which can be used in process models. Apart from the experimental results, a model based on population balances and heat and mass balances is presented. Simulations performed using the obtained empirical correlation are in good agreement with experimental data.
The obtained empirical correlations for the layer porosity depending on the drying conditions, represented by the drying potential, are shown. In the experiments, sodium benzoate was used as a coating material and porous γ-Al2O3 particles (left) as well as non-porous glass beads (right) were used as cores. Display omitted
•We measured layer porosities, produced at different drying conditions, with an X-ray microtomograph.•The measured porosities were correlated with the drying conditions.•A process model considering growth, developing porosity and drying was developed.•Simulations performed using the obtained empirical correlation are in good agreement with experimental data.
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