Trace Metals and Their Isotopes in the Tropical Atlantic Ocean - Cruise No. M81/1, February 04 – March 08, 2010, Las Palmas (Canary Islands, Spain) – Port of Spain (Trinidad & Tobago)

Summary Meteor Cruise M81/1 was dedicated to the investigation of the distribution of dissolved and particulate trace metals and their isotopic compositions (TEIs) in the full water column of the tropical Atlantic Ocean and their driving factors including main external inputs and internal cycling and ocean circulation. The research program is embedded in the international GEOTRACES program (e.g. Henderson et al., 2007), which this cruise was an official part of and thus corresponds to GEOTRACES cruise GA11. This cruise was completely dedicated to the trace metal clean and contamination-free sampling of waters and particulates for subsequent analyses of the TEIs in the home laboratories of the national and international participants. Besides a standard rosette for the less contaminant prone metals, trace metal clean sampling was realized by using a dedicated and coated trace metal clean rosette equipped with Teflon-coated GO-FLO bottles operated via a polyester coated cable from a mobile winch that was thankfully made available by the U.S. partners of the GEOTRACES program for this cruise. The particulate samples were also collected under trace metal clean conditions using established in-situ pump systems. The cruise track led the cruise southward from the Canary Islands to 11°S and then continued northwestward along the northern margin of South America until it reached Port of Spain, Trinidad & Tobago. The track crossed areas of major external inputs including exchange with the volcanic Canary Islands, the Saharan dust plume, as well as the plume of the Amazon outflow. In terms of internal cycling the equatorial high biological productivity band, as well as increased productivity associated with the Amazon Plume were covered. All major water masses contributing the Atlantic Meridional Overturning Circulation, as well as the distinct narrow equatorial surface and subsurface east-west current bands were sampled. A total of 17 deep stations were sampled for the different dissolved TEIs, which were in most cases accompanied by particulate sampling. In addition, surface waters were continuously sampled under trace metal clean conditions using a towed fish

Depth distribution of dissolved niobium in the (sub)tropical Atlantic Ocean

During research cruise M81/1 (GEOTRACES cruise GA11, RV Meteor, 04.02.-08.03.2010) 193 seawater samples were collected at 16 full water depth stations located in the (sub)tropical Atlantic. This cruise track covered an area from 30°N-11°S and 5°-50°W, which is characterized by different influencing parameters, e.g. dust input from the Saharan desert or riverine input from the Amazon. Seawater samples were collected with a trace metal clean CTD and filtration, subsampling and acidification was performed in the clean laboratory container onboard. Measurements were done land-based using an online-preconcentration method for the SeaFAST-system (ESI, seaFAST 1) with subsequent analysis by quadrupole inductively coupled plasma-mass spectrometry (Perkin-Elmer, ELAN DRC-e). Details on the preconcentration of Nb and the analytical measurement are provided in Poehle et al. 2015 (DOI: 10.1016/j.dsr.2014.11.014). Data on dissolved Nb in the Atlantic Ocean are scarce and this study may serve future studies on the chemical twin pairs Nb/Ta and Zr/Hf, which in combination is promising as a proxy for the paleo-ocean circulation. We observed an increase in concentration with depth contradicting the typical behavior of a particle-reactive element. Our results reveal that the influence of atmospheric dust input depends on its origin. While dust from the Canary Islands served as a source for Nb in surface waters dust particles from the Saharan desert worked as sorption sites. Since a correlation with nutrients (phosphate, nitrate, silicate) was not observed in this study Nb seems to be largely independent from nutrient cycling. Hence, distinct regional parameters influenced the depth distribution on a local scale while the observed concentration range of dissolved Nb in the (sub)tropical Atlantic agrees well with published data from the Pacific Ocean. The general depth profile of dissolved Nb with a slight surface depletion seems to be global feature

Forschungs- und Innovationsdynamik der Biotechnologie in sozialoekonomischer Sicht

UuStB Koeln(38)-910106730 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEManuskriptdr.DEGerman

Depth distribution of dissolved zirconium in the (sub)tropical Atlantic

Dissolved zirconium (Zr) is present in open-ocean seawater in low pmol/kg concentrations and studies for the Pacific Ocean reported an increase in concentration with depth although Zr is characterized as being particle-reactive. We observed the same pattern in this study and report the first data on dissolved Zr in the (sub)tropical Atlantic Ocean. We analyzed dissolved Zr in 194 Atlantic seawater samples (0.2 µm filtered) collected at 16 stations located in the (sub)tropical Atlantic during GEOTRACES cruise M81/1 (GEOTRACES cruise GA11, RV Meteor, 04.02.-08.03.2010). Seawater samples were collected with a trace metal clean CTD and filtration, subsampling and acidification was performed in the clean laboratory container onboard. Measurements were done using our newly developed online-preconcentration method for the SeaFAST-system (ESI, seaFAST 1) with subsequent analysis by quadrupole inductively coupled plasma-mass spectrometry (Perkin-Elmer, ELAN DRC-e). Details on the preconcentration of Zr and the analytical measurement are provided in Poehle et al. 2015 (doi:10.1016/j.dsr.2014.11.014). Our results showed an increase in dissolved Zr with depth with some distinct maxima at intermediate depths along a NE-SW transect (30°N to 12°S) in the Atlantic. Surface depletion was less pronounced along the Atlantic SE-NW transect (12°S to 8°N) and disappeared almost completely at the northernmost station at 8°N. We suggest that dust deposited off West Africa scavenged Zr from surface waters and riverine discharge from the Amazon may represent a source to the West Atlantic. The correlation of Zr with Si hints to a coupling of Zr to the uptake and release on and from Si particles such as biogenic opal. Remineralization of Si-particulates in deep waters release Zr which seems to be stabilized in the dissolved phase by complexation with e.g. organic ligands. This is supported by a sequential filtration approach (0.2 µm and 0.015 µm filter pore size) on seawater samples collected in the Pacific Ocean (research cruise SO229, 2011) showing that up to 91% of dissolved Zr in deep waters are present in the fraction < 0.015 µm. Hence, truly dissolved or colloidally bound Zr seems to a reasonable explanation for the observed increase in concentration with depth. Submitted data include the date of sample collection, geographic coordinates, depth and the concentration of dissolved Zr in pmol/kg

In Vitro Degradation Behavior and Biocompatibility of Bioresorbable Molybdenum

The degradation behavior and biocompatibility of pure molybdenum (Mo) were investigated. Dissolution of powder metallurgically manufactured and commercially available Mo was investigated by ion concentration measurement after immersion in modified Kokubo’s SBF (c-SBF-Ca) for 28 days at 37 °C and pH 7.4. Degradation layers and corrosion attack were examined with optical microscopy and REM/EDX analysis. Furthermore, potentiodynamic polarization measurements were conducted. Mo gradually dissolves in modified SBF releasing molybdate anions (MoO42−). The dissolution rate after 28 days is 10 µm/y for both materials and dissolution accelerates over time. A non-passivating, uniform and slowly soluble degradation product layer is observed. Additionally, apoptosis and necrosis assays with Mo ion extracts and colonization tests with human endothelial (HCAEC) and smooth muscle cell lines (HCASMC) on Mo substrates were performed. No adverse effects on cell viability were observed for concentrations expected from the dissolution of implants with typical geometries and substrates were densely colonized by both cell lines. Furthermore, Mo does not trigger thrombogenic or inflammatory responses. In combination with its favorable mechanical properties and the renal excretion of bio-available molybdate ions, Mo may be an alternative to established bioresorbable metals

Neue Techniken zur Kompostierung. Teilvorhaben 9: Zusammenhang zwischen mikrobieller Besiedlung und Geruchsemission. T. 1 Abschlussbericht

SIGLEAvailable from TIB Hannover: F96B1117+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

A local subset of mesenchymal cells expressing the transcription factor Osr1 orchestrates lymph node initiation

During development, lymph node (LN) initiation is coordinated by lymphoid tissue organizer (LTo) cells that attract lymphoid tissue inducer (LTi) cells at strategic positions within the embryo. The identity and function of LTo cells during the initial attraction of LTi cells remain poorly understood. Using lineage tracing, we demonstrated that a subset of Osr1-expressing cells was mesenchymal LTo progenitors. By investigating the heterogeneity of Osr1+ cells, we uncovered distinct mesenchymal LTo signatures at diverse anatomical locations, identifying a common progenitor of mesenchymal LTos and LN-associated adipose tissue. Osr1 was essential for LN initiation, driving the commitment of mesenchymal LTo cells independent of neural retinoic acid, and for LN-associated lymphatic vasculature assembly. The combined action of chemokines CXCL13 and CCL21 was required for LN initiation. Our results redefine the role and identity of mesenchymal organizer cells and unify current views by proposing a model of cooperative cell function in LN initiation

A local subset of mesenchymal cells expressing the transcription factor Osr1 orchestrates lymph node initiation

During development, lymph node (LN) initiation is coordinated by lymphoid tissue organizer (LTo) cells that attract lymphoid tissue inducer (LTi) cells at strategic positions within the embryo. The identity and function of LTo cells during the initial attraction of LTi cells remain poorly understood. Using lineage tracing, we demonstrated that a subset of Osr1-expressing cells was mesenchymal LTo progenitors. By investigating the heterogeneity of Osr1(+) cells, we uncovered distinct mesenchymal LTo signatures at diverse anatomical locations, identifying a common progenitor of mesenchymal LTos and LN-associated adipose tissue. Osr1 was essential for LN initiation, driving the commitment of mesenchymal LTo cells independent of neural retinoic acid, and for LN-associated lymphatic vasculature assembly. The combined action of chemokines CXCL13 and CCL21 was required for LN initiation. Our results redefine the role and identity of mesenchymal organizer cells and unify current views by proposing a model of cooperative cell function in LN initiation

Loss of BMP receptor type 1A in murine adipose tissue attenuates age-related onset of insulin resistance

Aims/hypothesis Adipose tissue dysfunction is a prime risk factor for the development of metabolic disease. Bone morphogenetic proteins (BMPs) have previously been implicated in adipocyte formation. Here, we investigate the role of BMP signalling in adipose tissue health and systemic glucose homeostasis. Methods: We employed the Cre/loxP system to generate mouse models with conditional ablation of BMP receptor 1A in differentiating and mature adipocytes, as well as tissue-resident myeloid cells. Metabolic variables were assessed by glucose and insulin tolerance testing, insulin-stimulated glucose uptake and gene expression analysis. Results: Conditional deletion of Bmpr1a using the aP2 (also known as Fabp4)-Cre strain resulted in a complex phenotype. Knockout mice were clearly resistant to age-related impairment of insulin sensitivity during normal and high-fat-diet feeding and showed significantly improved insulin-stimulated glucose uptake in brown adipose tissue and skeletal muscle. Moreover, knockouts displayed significant reduction of variables of adipose tissue inflammation. Deletion of Bmpr1a in myeloid cells had no impact on insulin sensitivity, while ablation of Bmpr1a in mature adipocytes partially recapitulated the initial phenotype from aP2-Cre driven deletion. Co-cultivation of macrophages with pre-adipocytes lacking Bmpr1a markedly reduced expression of proinflammatory genes. Conclusions/interpretation Our findings show that altered BMP signalling in adipose tissue affects the tissue’s metabolic properties and systemic insulin resistance by altering the pattern of immune cell infiltration. The phenotype is due to ablation of Bmpr1a specifically in pre-adipocytes and maturing adipocytes rather than an immune cell-autonomous effect. Mechanistically, we provide evidence for a BMP-mediated direct crosstalk between pre-adipocytes and macrophages. Electronic supplementary material The online version of this article (doi:10.1007/s00125-016-3990-8) contains peer-reviewed but unedited supplementary material, which is available to authorised users