Halogens have, because of their volatile behavior and incompatibility, the potential to act as key tracers of volatile transport processes within the Earth's mantle. A better understanding of halogen ...behavior during partial melting processes will improve our understanding of volatile input mechanisms into the Earth's mantle and give insight into its evolution over the Earth's history. This study introduces time of flight secondary ion mass spectrometry (TOF-SIMS) as an analytical method for the determination of halogen partition coefficients and significantly extends the available dataset for fluorine and chlorine partitioning between mantle minerals and silicate melts to conditions of partial melting processes in Ocean Island Basalt (OIB) source regions.
Halogen partitioning between olivine, orthopyroxene and silicate melt has been determined in experiments at 1.0–2.3GPa and 1350–1600°C. Combining our data with results of recent studies (O'Leary et al., 2010; Beyer et al., 2012; Dalou et al., 2012, 2014; Rosenthal et al., 2015) shows that fluorine and chlorine partitioning between olivine and melt increases by about 1.5–2 orders of magnitude between 1350°C and 1600°C (fluorine: 0.005(3)–0.31(16); chlorine: 0.005(45)–0.17(9)) and does not show any pressure dependence between 1.0 and 2.3GPa. Chlorine partitioning between orthopyroxene and melt increases by about 1 order of magnitude between 1450°C and 1600°C (0.015(8)–0.16(9)) at a constant pressure of 2.3GPa. Fluorine partitioning between orthopyroxene and melt increases by 1.5 orders of magnitude between 1250°C and 1600°C (0.029(6)–0.20(14)) and does not show any pressure dependence.
Transmission electron microscopy measurements show that halogens are not incorporated in the form of humite-type defects in olivine. The most reasonable incorporation mechanism for halogens is via point defects in the olivine and orthopyroxene lattice, where they are inferred to be charge-balanced via oxygen defects.
By combining our partition coefficients with natural halogen concentrations in oceanic basalts, we are able to give estimates for fluorine and chlorine abundances in Mid Ocean Ridge Basalt (MORB) (F=3–14; Cl=0.6–14ppm) and OIB (F=34–76; Cl=21–71ppm) mantle source regions. Comparing these with estimates of bulk silicate Earth (BSE) concentrations (F=18±8ppm, Lyubetskaya and Korenaga, 2007; F=25±10ppm, Palme and O'Neill, 2003; Cl=30±12ppm Palme and O'Neill, 2003) indicates that the upper mantle is degassed by 22–88% in fluorine and 22–99% in chlorine relative to the primitive mantle. The OIB source mantle region has a chlorine concentration that is similar to primitive mantle estimates, but is enriched in fluorine by a factor of 1.4–4.2 relative to the primitive mantle. An explanation for the relative fluorine enrichment in the OIB source region is that compared to chlorine, fluorine may be incorporated to a greater extent into the crystal structure of minerals that are stable at high P–T conditions and may thus be recycled more efficiently into the deeper mantle through subduction of oceanic crust.
•New experimental data describe the F and Cl partitioning between mantle minerals and melt in MORB and OIB source regions.•Introduction of a TOF-SIMS technique for measuring halogens•Halogens are incorporated as point defects in the olivine and orthopyroxene lattice.•Cl and F are both depleted relative to BSE in the MORB source but equal (Cl) or are greater (F) than BSE in the OIB source.•Excess F in the OIB source suggests that F and Cl are partially separated during subduction.
A rapid decarbonization of the energy sector is key for mitigating climate change and in this transformation a transition to renewable heating is essential. To date, most attention in both research ...and policy on decarbonization has been on electricity and transport systems, with less interest in the heating system. Half of the EU's final energy consumption is made up by the heating and cooling sector, making this an important sector for reducing fossil fuel consumption. This article addresses the lack of research on decarbonization of heating by answering the question, what barriers and drivers do Thermal Energy Communities (TECs) perceive when trying to enter the market and play a role in the decarbonization of heating in Germany? Eight TECs and four umbrella organizations in Germany have been interviewed about their experiences of initiating and running a TEC. The results show, amongst others, that the political support of municipalities is put forward as an essential driver and important factor for success. However, barriers for municipalities to get involved were often that they lacked expertise, capacity and financial resources. An important driver for TECs was the involvement of local experts and professionals who could support the volunteers often in charge of a TEC. The results show that TECs that included professionals had an advantage in building heating systems, as they could better address their complexity and high initial costs. Another prevalent result was the need for community engagement and citizen mobilization, which is a greater need in heating projects compared to those focusing on electricity, due to community heating systems requiring a substantial number of customers for profitability.
This paper presents results from an empirical study on number and person agreement with disjoined subjects in Standard German. We show that disjunctive agreement resolves to plural if one or both of ...the disjuncts are plural. The main empirical finding of the paper is that if both disjuncts are singular, verbal agreement is either singular or plural, irrespective of the relative order of subject and verb. We account for this observation in an Optimality Theoretic approach by assuming that the verb has to agree with each disjunct as well as with the disjunction itself, which bears a special kind of plural feature. The number feature of the verb has to match the number feature of both the disjunction and the disjuncts. This can lead to potential conflicts which as we show is the source of agreement optionality in case of singular disjunctions. Further, we discuss the effects of mismatching person in disjunctions, the effects of syncretic verb forms, as well as word order effects. Importantly, we observe that closest conjunct agreement is not consistently available in German. Finally, we present a brief excursus to agreement with disjoined subjects in other languages and discuss how data from Somali, Slovenian, and Hebrew fit into our analysis.
Dipeptidylpeptidase (DPP)-4 is a key regulator of the incretin system. For several years DPP-4 inhibitors in addition to GLP-1 analogues are of major importance in the clinical management of obesity ...and type 2 diabetes. DPP-4 is also known as CD26 and represents a membrane bound protease on the surface of several eukaryotic cell types. Of interest, DPP-4, like ACE2, has been shown to serve as a binding partner for corona-like viruses to enter host immune cells. Since metabolic diseases are major risk factors for the present COVID-19 pandemic, we examined circulating soluble DPP-4 serum concentrations in patients suffering from severe COVID-19 infection and in healthy human subjects in a case control design. In this analysis sDPP-4 levels were significantly lower in COVID-19 patients compared to controls (242.70 plus or minus 202.12 ng/mL versus 497.70 plus or minus 188.13 ng/mL, p = 0.02). We also examined sDPP-4 serum concentrations in patients suffering from sepsis not due to corona-like viruses. In these subjects, sDPP-4 levels were not different compared to healthy case controls (p = 0.14), which might suggest the decrease of sDPP-4 to be specific for corona-like virus infections. Currently, most data point towards membrane bound ACE2 in contrast to DPP-4 as the major binding partner for COVID-19 internalization into host immune cells. However, the finding that the circulating soluble form of DPP-4 is reduced in hospitalized patients might suggest a regulatory role for both, ACE and DPP-4, in COVID-19 infections, especially since obesity and type 2 diabetes are major risk factor for a severe course of the disease
Hartmann offers her perspective on the future of midwifery education in Germany. Based on current developments in Germany, the maternity workforce of the future will become more highly specialized ...and diversified. The workforce is likely to include not only midwives and obstetricians, but doulas, postnatal educators, birth coaches, diaper free coaches or sleep coaches, as well as pediatricians and lactation consultants.
The accent pattern known as verum focus is commonly understood as an ordinary alternative focus on the truth of a proposition. This standard view, which we call the focus accent thesis (FAT), can be ...contrasted with the lexical operator thesis (LOT), according to which the accent pattern that looks like focus in languages like German or English is actually not an instance of focus marking, but realizes a lexical verum predicate, whose function is to relate the current proposition to a question under discussion. Although it is hard to distinguish between the FAT and the LOT on the basis of German or English, a broader cross-linguistic perspective seems to favor the LOT. Drawing from fieldwork on Tsimshianic (Gitksan) and Chadic (Bura, South Marghi), we first show that in none of these languages is verum realized in the same way that ordinary alternative focus is marked. This sheds initial doubt on the unity of verum and focus. Secondly, the FAT predicts that a language cannot have co-occuring verum and focus, if it does not allow multiple foci, and that a language should allow them to co-occur if it allows for multiple foci. Again, while it is hard to find counterexamples in German or English, some of the data from our cross-linguistic investigation favor the LOT.
Recent rodent microbiome experiments suggest that besides Akkermansia, Parasutterella sp. are important in type 2 diabetes and obesity development. In the present translational human study, we aimed ...to characterize Parasutterella in our European cross-sectional FoCus cohort (n = 1,544) followed by validation of the major results in an independent Canadian cohort (n = 438). In addition, we examined Parasutterella abundance in response to a weight loss intervention (n = 55). Parasutterella was positively associated with BMI and type 2 diabetes independently of the reduced microbiome α/β diversity and low-grade inflammation commonly found in obesity. Nutritional analysis revealed a positive association with the dietary intake of carbohydrates but not with fat or protein consumption. Out of 126 serum metabolites differentially detectable by untargeted HPLC-based MS-metabolomics, L-cysteine showed the strongest reduction in subjects with high Parasutterella abundance. This is of interest, since Parasutterella is a known high L-cysteine consumer and L-cysteine is known to improve blood glucose levels in rodents. Furthermore, metabolic network enrichment analysis identified an association of high Parasutterella abundance with the activation of the human fatty acid biosynthesis pathway suggesting a mechanism for body weight gain. This is supported by a significant reduction of the Parasutterella abundance during our weight loss intervention. Together, these data indicate a role for Parasutterella in human type 2 diabetes and obesity, whereby the link to L-cysteine might be relevant in type 2 diabetes development and the link to the fatty acid biosynthesis pathway for body weight gain in response to a carbohydrate-rich diet in obesity development.
Gut microbiota represent a potential novel target for future prediabetes and type 2 diabetes therapies. In that respect, niacin has been shown to beneficially affect the host-microbiome interaction ...in rodent models.
We characterized more than 500 human subjects with different metabolic phenotypes regarding their niacin (nicotinic acid NA and nicotinamide NAM) status and their gut microbiome. In addition, NA and NAM delayed-release microcapsules were engineered and examined in vitro and in vivo in two human intervention studies (bioavailability study and proof-of-concept/safety study).
We found a reduced α-diversity and
abundance in the microbiome of obese human subjects associated with a low dietary niacin intake. We therefore developed delayed-release microcapsules targeting the ileocolonic region to deliver increasing amounts of NA and NAM to the microbiome while preventing systemic resorption to avoid negative side effects (e.g., facial flushing). In vitro studies on these delayed-release microcapsules revealed stable conditions at pH 1.4, 4.5, and 6.8, followed by release of the compounds at pH 7.4, simulating the ileocolonic region. In humans in vivo, gut-targeted delayed-release NA but not NAM produced a significant increase in the abundance of
. In the absence of systemic side effects, these favorable microbiome changes induced by microencapsulated delayed-release NA were associated with an improvement of biomarkers for systemic insulin sensitivity and metabolic inflammation.
Targeted microbiome intervention by delayed-release NA might represent a future therapeutic option for prediabetes and type 2 diabetes.
Yb-Y inter-diffusion along a single grain boundary of a synthetic yttrium aluminium garnet (YAG) bicrystal has been studied using analytical transmission electron microscopy (ATEM). To investigate ...the diffusion, a thin-film containing Yb as the diffusant was deposited perpendicular to the bicrystal grain boundary by pulsed laser deposition (PLD). Structural properties and their change with time in both the diffusant source and the grain boundary are reported. The diffusion profiles are incorporated in a numerical diffusion model, which is applied to determine the grain boundary diffusion coefficient,
D
gb
, at 1.723 K it is equal to 3 × 10
−15
m
2
/s. We find that grain boundary diffusion is 4.85 orders of magnitude faster than volume diffusion, which was determined from the same diffusion experiment. This result is discussed in the context of special versus general grain boundaries. Finally, we successfully tested the capability of synchrotron-based nano-X-ray fluorescence analysis to map micro-chemical patterns in two dimensions with sub-micrometre resolution.
Obesity and type 2 diabetes (T2D) show an increased risk for a severe COVID-19 disease. Treatment with DPP4 inhibitor (DPP4i) results in reduced mortality and better clinical outcome. Here, we aimed ...to identify potential mechanisms for the observed DPP4i effect in COVID-19. Comparing T2D subjects with and without DPP4i treatment, we identified a significant increase of the anti-inflammatory adipokine sFRP5 in relation to DPP4 inhibition. sFRP5 is a specific antagonist to Wnt5a, a glycopeptide secreted by adipose tissue macrophages acting pro-inflammatory in various diseases. We therefore examined sFRP5 levels in patients hospitalised for severe COVID-19 and found significant lower levels compared to healthy controls. Since sFRP5 might consequently be a molecular link for the beneficial effects of DPP4i in COVID-19, we further aimed to identify the exact source of sFRP5 in adipose tissue on cellular level. We therefore isolated pre-adipocytes, mature adipocytes and macrophages from adipose tissue biopsies and performed western-blotting. Results showed a sFRP5 expression specifically in mature adipocytes of subcutaneous and omental adipose tissue. In summary, our data suggest that DPP4i increase serum levels of anti-inflammatory sFRP5 which might be beneficial in COVID-19, reflecting a state of sFRP5 deficiency.
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