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Determining past changes in ocean circulation on the Antarctic margin is important for understanding the interactions between climate, circulation, and ice sheet retreat. However, the application of neodymium isotopes (εNd), a well-known proxy of ocean circulation, is limited on the Antarctic margin, due to the lack of carbonate preservation and inconsistency in authigenic εNd leached from bulk sediment. Here we assess the use of the εNd proxy along the continental rise of Wilkes Land, by combining analyses of seawater with phases extracted using a 10-second reductive leach in co-located surface sediments. Dissolved seawater εNd values displayed the following water mass signatures; εNd = −8.8 ± 0.2 (n = 1) for Antarctic Surface Water; εNd = −9.7 ± 0.2 (n = 2) for Winter Water; and εNd = −8.7 ± 0.3 (n = 6) for modified Circumpolar Deep Water. The sediment leachate did not reproduce a bottom water Nd signature and yielded a very variable εNd, ranging from −10.4 to −14.4. In contrast, the bulk detrital sediment εNd fell within a narrow range of −13.1 ± 0.5 (n = 29). Examination of elemental ratios and rare earth element (REE) anomalies indicates that the leaching procedure extracts exclusively authigenic phases. The strong relationship found between phosphorus (P) and REE suggests that a P-associated phase is the main REE host-phase leached, as opposed to ferromanganese oxyhydroxides. The leached europium anomalies and εNd indicate that the extracted Nd signature is influenced by two end members, one with a seawater-like εNd (∼-8) and one more negative than the bulk detritus (εNd ∼−14). Finally, the decoupling between [Nd] and εNd, as well the distinct middle-REE enrichments measured in the leach implies the authigenic εNd is controlled by diagenesis. We thus infer that the Nd signature of the leached phosphates is derived from porewater and influenced by the presence of a reactive detrital component in the sediment. Unradiogenic reactive sedimentary phases which easily dissolve into porewaters are likely sourced from the subglacial erosion of ancient metasediments and crustal remnants on the Wilkes Land coast. These new εNd data contribute to the evaluation of the εNd proxy at complex, dynamic and under-studied interfaces such as the East Antarctic margin. However, further work is still needed to develop reliable proxies of past Antarctic water masses., Geochimica et Cosmochimica Acta, 344, ISSN:0016-7037, ISSN:1872-9533

The interaction of water with oriented NiO films is studied by using a combination of photoelectron spectroscopy with in situ sample preparation and electrochemical measurements in the stability window of water. In contrast to NiO(100), room temperature water exposure induces a downward band bending on the (110)- and (111)-oriented films, indicating a more positive surface charge. The surface charge is assigned to a dissociative adsorption of water accompanied by a removal of oxygen, which corresponds to a preferential adsorption of protons. Photoelectron spectroscopy suggests that the nonstoichiometric adsorption is related to the presence of adsorbed oxygen species prior to water exposure. For the NiO(110) surface, the stability of adsorbed bridging oxygen dimers is confirmed by density functional theory calculations. The preferential adsorption of protons, which requires interaction of two water molecules with the oxygen dimers, explains that water acts as an electron donor on many oxide surfaces. The different adsorption behavior is consistent with a lower electrochemical activity of the (110)- and (111)-oriented surfaces toward hydrogen adsorption due to an effective reduction of Lewis base sites.

Dislocations in oxides can be described as charged line defects and means for one-dimensional doping, which can tune electrical and thermal properties. Furthermore, theoretically it was shown that dislocations can pin ferroelectric domain walls. Broader application of this concept hinges on the development of a methodology to avail this approach to polycrystalline ceramics. To this end, we use different creep mechanisms as a method to introduce multidimensional defects and quantify structural changes. A deformation map for fine-grained barium titanate is provided and the influences of the defects and creep regimes are correlated in this first study to modifications of electrical conductivity, dielectric, ferroelectric, and piezoelectric properties. A plastic deformation of 1.29% resulted in an increase in the Curie temperature by 5 degrees C and a decrease in electromechanical strain by 30%, pointing toward electromechanical hardening by dislocations.

Verschleißerscheinungen an Verzahnungsschleifmaschinen treten oft unerwartet erst nach Jahren der Nutzung auf – und wirken sich schlagartig auf die Verzahnungsqualität aus. Eine zyklische Diagnose des Maschinenzustands kann für Abhilfe sorgen. Hierfür gibt es jetzt „Argus“.

While scientific practices are internationally considered as an integral part of science instruction to achieve scientific literacy, only scarce knowledge exists about their common implementation in everyday science lessons. In contrast to prior studies, which used either only a small selection of lessons or relied on self-reported data from teachers, our study builds on a large-scale observational study to investigate the frequency, duration, and social settings of experiments, microscopy, the use of models, and dissection in biology education. As part of their professional development, biology pre-service teachers observed 2556 biology lessons, of which only 762 lessons (29.8%) included at least one scientific practice. Inspecting the duration of the specific methods allowed for a more pronounced view, showing that for example experiments were only conducted in 2:18 minutes in a hypothetical 45-minute lesson. These Experiments (n = 308) were mainly applied in group settings (39%), microscopy (n = 86) most often in partner settings (67.8%), and modelling (n = 418) occurred mainly in teacher-centered settings (68.4%). Using regression analyses we found variables such as school track, grade level, class size, and room conditions to be significant predictors, highlighting relevant variables that may hinder biology teachers from implementing scientific practices into their lessons. Overall, with the results of this large-scale observation study we add relevant knowledge about scientific practices, which can be used for supporting the implementation of more scientific practices through teacher training, learning materials, and school development, respectively.

The introduction of dislocations is a recently proposed strategy to tailor the functional and especially the electrical properties of ceramics. While several works confirm a clear impact of dislocations on electrical conductivity, some studies raise concern in particular when expanding to dislocation arrangements beyond a geometrically tractable bicrystal interface. Moreover, the lack of a complete classification on pertinent dislocation characteristics complicates a systematic discussion and hampers the design of dislocation-modified electrical conductivity. We proceed by mechanically introducing dislocations with three different mesoscopic structures into the model material single-crystal SrTiO3 and extensively characterizing them from both a mechanical as well as an electrical perspective. As a final result, a deconvolution of mesoscopic structure, core structure, and space charge enables us to obtain the complete picture of the effect of dislocations on functional properties, focusing here on electric properties.

The remarkable ability of biological systems to specifically recognize, sort, and process molecules encourages the development of novel bio-inspired membranes and interfaces. Herein, we focus on the functionalization of amphiphilic polystyrene-block-poly(2-hydroxyethyl methacrylate) (PS-b-PHEMA) with the amino acid glycine yielding polar block segments with primary amine functionalities. Excellent control over the tailored block copolymer (BCP) synthesis and functionalization is proven by size exclusion chromatography (SEC), 1H solution NMR, and 15N solid state NMR spectroscopy. For the first time, BCPs containing primary amines were used for the self-assembly and non-solvent induced phase separation (SNIPS) process for the preparation of isoporous and integral asymmetric membranes. Hexagonally arranged open pores with diameters of 19 nm were obtained as shown by scanning electron microscopy (SEM), atomic force microscopy (AFM), and pH-dependent water flux measurements. Additionally, the primary amine was...

Atomic force microscopy allows for the nanomechanical surface characterization of a multitude of types of materials with highest spatial precision in various relevant environments. In recent years, researchers have refined this methodology to analyze living biological materials in vitro. The atomic force microscope thus has become an essential instrument for the (in many cases) non-destructive, high-resolution imaging of cells and visualization of their dynamic mechanical processes. Mapping force versus distance curves and the local evaluation of soft samples allow the operator to "see" beneath the sample surface and to capture the local mechanical properties. In this work, we combine atomic force microscopy with fluorescence microscopy to investigate cancerous epithelial breast cells in culture medium. With unprecedented spatial resolution, we provide tomographic images for the local elasticity of confluent layers of cells. For these particular samples, a layer of higher elastic modulus located directly beneath the cell membrane in comparison with the average elastic properties was observed. Strikingly, this layer appears to be perforated at unique locations of the sample surface of weakest mechanical properties where distinct features were visible permitting the tip to indent farthest into the cell's volume. We interpret this layer as the cell membrane mechanically supported by the components of the cytoskeleton that is populated with sites of integral membrane proteins. These proteins act as breaking points for the indenter thus explaining the mechanical weakness at these locations. In contrast, the highest mechanical strength of the cell was found at locations of the cell cores as cross-checked by fluorescence microscopy images of staining experiments, in particular at nucleoli sites as the cumulative elastic modulus there comprises cytoskeletal features and the tight packing ribosomal DNA of the cell.

[EN] Several different instruments have been introduced into the market to obtain good color characterization for different measurement configurations. These commercial instruments have different optical and working configurations, however, the measurement data provided by each instrument should be similar to have good consistency when comparing them to each other measuring the same sample material. Therefore, the purpose of this work was to apply an inter-model agreement study of spectral and colorimetric data of three instruments (CM-M6, BYK-mac-I, and MA98). Two different statistical tests were applied following ASTM recommendations. In general, the measurement geometries close to the specular direction and the flop direction showed greater deviations. In addition, the partial color differences calculated for the comparison of MA98 versus CM-M6 were larger than the BYK-mac-i versus CM-M6 comparison. Finally, it can be concluded that most of the measurement geometries were statistically significantly different from each other which means that these differences were due to systematic or bias errors and not exclusively to random errors., EMRP, Grant/Award Numbers: Bidirectional reflectance definitions (16NRM08), 16NRM08; Spanish Ministry of Economy and Competitiveness, Grant/Award Number: DPI2015-65814-R; Ministry of Economy and Competitiveness, Grant/Award Number: DPI2015-65814-R; European Union; EURAMET

To improve the reactivity of lignin for incorporation into high value polymers, the introduction of amines via Mannich reaction is a commonly used strategy. During this functionalization reaction, intra- as well as intermolecular lignin–lignin crosslinking occurs, which can vastly change the elastic properties of the lignin, and therefore, the properties of the resulting polymer. Therefore, the molecular structure of the amine that is used for such a lignin functionalization may be of great importance. However, the relationship between the molecular structure of the amine and the elastic properties of the lignin-based polymer that is generated thereof, has not been fully understood. Herein, this relationship was investigated in detail and it was observed that the molecular flexibility of the amines plays a predominant role: The use of more flexible amines results in an increase in elasticity and the use of less flexible amines yields more rigid resin material. In addition to the macroscopic 3-point bending flexural tests, the elastic modules of the resins were determined on the nanometer scale by using atomic force microscopy (AFM) in the PeakForce tapping modus. Thus, it could be demonstrated that the intrinsic elasticities of the lignin domains are the main reason for the observed tendency.

The Hera Au-Ag-Pb-Zn deposit of central NSW, Australia with a total resource of 3.6 Mt @ 3.3g/T Au, 25g/T Ag, 2.6% Pb and 3.8% Zn occurs on the SE margin of the Cobar Basin. It is hosted by the shallow marine Mouramba Group and overlying turbiditic Amphitheatre Group. The siltstones comprise various mixtures of quartz, plagioclase, muscovite-phengite, biotite and clinochlore, along with relatively abundant accessory titanite and ilmenite. The deposit comprises a number of discrete lodes which are steeply west-dipping and strike NNW. Each lode has different abundances of the main ore minerals sphalerite, galena, chalcopyrite, pyrrhotite and gold. The North Pod and Far West lenses have the most diverse ore mineralogy in addition containing arsenopyrite, native silver, gudmundite, Ag-tetrahedrite, acanthite, dyscrasite, native antimony, nisbite and breithauptite. Electrum (continuous spectrum from Ag-rich to Au-rich) is associated with sulfides in the main ore lenses while native gold occurs in the host rocks along cleavages and away from the main ore. Most of the deposit has experienced greenschist facies metamorphism with pervasive green chlorite alteration, though the North Pod differs in being distinctly Ag and Sb rich and has reached at least amphibolite facies metamorphism with a garnet-wollastonite-vesuvianite-tremolite assemblage. Tremolite is relatively abundant throughout a number of the other lodes suggesting widespread low-T skarn alteration. Cross-cutting pegmatites comprise quartz, plagioclase (labradorite-andesine) and microcline. Scheelite is relatively abundant in the upper levels of the deposit, most commonly in cross-cutting quartz veins.

The intermediate-sulfidation epithermal Kylo deposit is part of the Drake Goldfield of north-eastern NSW. The mineralization is gold-dominant with minor silver and significant levels of zinc, copper and lead. Kylo has a resource of 2.298 Mt @ 1.23g/T Au and 1.35 g/T Ag. Mineralization mainly occurs in the form of vein stockworks. Petrographic and SEM analysis show that there are at least three mineralization events, with Au mineralization strongly associated with at least a deposit-scale alteration event. Quantitative XRD analysis shows a strong positive correlation between Au-mineralization and argillic-phyllic alteration. Electrum was found as inclusions in massive sphalerite in the main mineralization stage. Correlation analysis for the assay data indicates that Au has a strong relation with Ag and moderate correlation with Pb. Petrographic and geochemical analysis has identified three lithologies, rhyolite, rhyodacite/dacite and andesite, with Au mineralization more associated with the rhyodacites, while at deeper levels some of the andesites also show a relatively strong correlation with Au. Sr shows a significant strong depletion, due to the intense and pervasive alteration at Kylo. The andesitic volcanics show moderate LREE enrichment with small negative Eu anomalies, and relative depletion in Nb, Ta and Ti, indicating an island arc tectonic setting. The carbon and oxygen isotopes of late-stage vein carbonates suggest that the fluid was derived from a magmatic source with a significant influence of low-temperature alteration, while the sulfur isotopes indicate a magmatic sulfur source.

The intermediate-sulfidation epithermal Strauss deposit is part of the Drake Goldfield of north-eastern NSW. The mineralisation in this deposit is gold-dominant with minor silver and significant levels of zinc, copper and lead. Strauss has a combined total resource of 2.66 Mt @ 1.5g/T Au and 1.9g/T Ag. Mineralisation mainly occurs in the form of vein stockworks of three main orientations. Structural analysis indicates these to be the result of two fault system events and one conjugate fault system. Petrographic and SEM analysis shows that there are two separate mineralisation styles, a pyrite dominant and sphalerite dominant style, with at least three mineralisation events. Correlation analysis for the assay data indicates that Au has a strong relation with Ag and moderate correlation with Pb. Petrographic analysis has shown the deposit to be made-up of varying layers of dacitic ash flow tuffs and a cross-cutting lamprophyre dyke though previous authors classified some of the tuffs as intrusive andesites. XRD analysis indicates widespread argillic-phyllic and propylitic alteration. Silver tellurides have been found as late-stage grains associated with sphalerite mineralisation. Sr shows a significant strong depletion, due to the intense and pervasive alteration at Strauss. The carbon and oxygen isotopes of vein carbonates suggest that the carbon from the late-stage carbonates was derived from a magmatic source with a significant influence of low-temperature meteoric water alteration, while the sulphur isotopes indicate a magmatic sulphur source.

The newly discovered Federation deposit, with a resource estimate of 2.6 Mt @ 7.7% Pb, 13.5% Zn, 0.8 g/t Au, and 9 g/t Ag, lies 10 km south of the Hera deposit within the Cobar Basin of the Lachlan Orogen. Located just north of the Erimeran Granite contact and between the Lower Amphitheatre Group and underlying shallow marine Mouramba Group Roset Sandstone, the host siltstones and sandstones have been brecciated, intensely silicified, and chloritized close to mineralization. Oriented in an overall east-northeast strike and with a steep south-southeast dip, the siltstones mainly comprise quartz, clinochlore, biotite, and muscovite. Federation also has highly fragmented zones with breccia and vein-fill of calcite. The main ore mineralization includes sphalerite and galena, with lesser chalcopyrite, pyrrhotite, pyrite, gold, and very rare meneghinite. Mineralization occurs within silicified veins and breccias of Zn-Pb sulfides, which generally grade to moderate veining of sulfides with Pb and Cu dominant sulfides, as well as minor veining of base metals associated with visible gold. Mineralization throughout the deposit is fairly simple, with a low diversity of minerals. Iron concentration varies throughout the deposit, decreasing towards the center. Observations of massive sphalerite with gradations of red to honeycomb yellow indicate the transition from high Fe (7–10%) to low Fe (2–5%) within the coarse sulfide assemblages over a very short distance. Within the main mineralized corridor, fibrous amphibole inclusions within galena/sphalerite assemblages are observed at 251 m, as well as epidote associated with sulfides at 573 m. Other ore-associated gangue minerals include ilmenite, siderite, scheelite, magnetite, apatite, and rutile.

The introduction of dislocations is a recently proposed strategy to tailor the functional and especially the electrical properties of ceramics. While several works confirm a clear impact of dislocations on electrical conductivity, some studies raise concern in particular when expanding to dislocation arrangements beyond a geometrically tractable bicrystal interface. Moreover, the lack of a complete classification on pertinent dislocation characteristics complicates a systematic discussion and hampers the design of dislocation-modified electrical conductivity. We proceed by mechanically introducing dislocations with three different mesoscopic structures into the model material single-crystal SrTiO