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For the past 20 years, LA-ICP-MS has been the method of choice to quantify element concentrations in fluid inclusions hosted in geological samples. However, the ablation of fluid inclusions typically produces short, transient signals that are difficult to representatively sample with sequential analysis inherent to single collector ICP-MS instruments, especially considering small inclusions (<20 µm) and/or low-concentration elements (<10 µg g−1). This issue can be overcome by significantly reducing quadrupole settling times, allowing faster cycling through a given element list at constant duty cycle and therefore, better temporal resolution of the signal. In this note, we present results from already well-characterized fluid inclusion assemblages performed with a "fast-scanning" quadrupole ICP-MS, i.e. characterized by extremely short settling times (default 0.2 ms and down to 0.065 ms). This capability, which does not impede basic instrument performance, improves the results of LA-ICP-MS fluid inclusion analyses in three ways. First, it extends the possibility to accurately and reproducibly quantify element concentrations to fluid inclusions down to <10 µm in size, with absolute detection limits in the same range as using a conventional quadrupole. Second, it releases the need to compromise between full chemical characterization of the fluids and accurate determination of some key elements of interest, as short settling times offer the possibility to rapidly scan through extensive element lists (e.g. 52 elements cycled in 52 ms at 80% duty cycle in the tests presented here). Third, it improves accuracy and precision for analytes hosted in small daughter crystals in assemblages of complex, polyphase fluid inclusions. [ABSTRACT FROM AUTHOR]

The improvement of cell specific productivities for the formation of therapeutic proteins is an important step towards intensified production processes. Among others, the induction of the desired production phenotype via proper media additives is a feasible solution provided that said compounds adequately trigger metabolic and regulatory programs inside the cells. In this study, S‐(5′‐adenosyl)‐ l‐methionine (SAM) and 5′‐deoxy‐5′‐(methylthio)adenosine (MTA) were found to stimulate cell specific productivities up to approx. 50% while keeping viable cell densities transiently high and partially arresting the cell cycle in an anti‐IL‐8‐producing CHO‐DP12 cell line. Noteworthy, MTA turned out to be the chemical degradation product of the methyl group donor SAM and is consumed by the cells. [ABSTRACT FROM AUTHOR]

Increasing markets for biopharmaceuticals, including monoclonal antibodies, have triggered a permanent need for bioprocess optimization. Biochemical engineering approaches often include the optimization of basal and feed media to improve productivities of Chinese hamster ovary (CHO) cell cultures. Often, l‐tyrosine is added as dipeptide to deal with its poor solubility at neutral pH. Showcasing IgG1 production with CHO cells, we investigated the supplementation of three l‐tyrosine (TYR, Y) containing dipeptides: glycyl‐l‐tyrosine (GY), l‐tyrosyl‐l‐valine (YV), and l‐prolyl‐l‐tyrosine (PY). While GY and YV led to almost no phenotypic and metabolic differences compared to reference samples, PY significantly amplified TYR uptake thus maximizing related catabolic activity. Consequently, ATP formation was roughly four times higher upon PY application than in reference samples. [ABSTRACT FROM AUTHOR]

Understanding the formation of economically important porphyry Cu--Au deposits requires knowledge of the magmatic-to-hydrothermal processes that act within the much larger magmatic system and the timescales on which they occur. We apply high-precision zircon geochronology (chemical abrasion--isotope dilution--thermal ionisation mass spectrometry; CA--ID--TIMS) and spatially resolved zircon geochemistry (laser ablation inductively coupled plasma mass spectrometry; LA-ICP-MS) to constrain the magmatic evolution of the underlying magma reservoir at the Pliocene Batu Hijau porphyry Cu--Au deposit. We then use this extensive dataset to assess the accuracy and precision of different U--Pb dating methods of the same zircon crystals. Emplacement of the oldest pre- to syn-ore tonalite (3:736 ± 0:023 Ma) and the youngest tonalite porphyry to cross-cut economic Cu--Au mineralisation (3:646 ± 0:022 Ma) is determined by the youngest zircon grain from each sample, which constrains the duration of metal precipitation to fewer than 90 ± 32 kyr. Overlapping spectra of single zircon crystallisation ages and their trace element distributions from the pre-, syn and post-ore tonalite porphyries reveal protracted zircon crystallisation together with apatite and plagioclase within the same magma reservoir over > 300 kyr. The presented petrochronological data constrain a protracted early > 200 kyr interval of melt differentiation and cooling within a large heterogeneous magma reservoir, followed by magma storage in a highly crystalline state and chemical and thermal stability over several tens of thousands of years during which fluid expulsion formed the ore deposit. Irregular trace element systematics suggest magma recharge or underplating during this final short time interval. The comparison of high-precision CA--ID--TIMS results with in situ LA-ICP-MS and a sensitive high-resolution ion microprobe (SHRIMP) U--Pb geochronology data from the same zircon grains allows a comparison of the applicability of each technique as a tool to constrain dates and rates on different geological timescales. All techniques provide accurate dates but with different precision. Highly precise dates derived by the calculation of the weighted mean and standard error of the mean of the zircon dates obtained by in situ techniques can lead to ages of unclear geological significance that are older than the maximum ages of emplacement given by the CA--ID--TIMS ages of the youngest zircons in each sample. This lack of accuracy of the weighted means is due to the protracted nature of zircon crystallisation in upper crustal magma reservoirs, suggesting that standard errors should not be used as a means to describe the uncertainty in those circumstances. We conclude from this and similar published studies that the succession of magma and fluid pulses forming a single porphyry deposit and similarly rapid geological events are too fast to be reliably resolved by in situ U--Pb geochronology and that assessing the tempo of ore formation requires CA--ID--TIMS geochronology. [ABSTRACT FROM AUTHOR]

The Fehmarn Belt is a key area for the Late Pleistocene and Holocene development of the Baltic Sea as it was a passage for marine and fresh water during its different stages. The pre‐Holocene geological development of this area is presented based on the analysis of seismic profiles and sedimentary gravity cores. Late Pleistocene varve sediments of the initial Baltic Ice Lake were identified. An exceptionally thick varve layer, overlain by a section of thinner varves with convolute bedding in turn covered by undisturbed varves with decreasing thicknesses is found in the Fehmarn Belt. This succession, along with a change in varve geochemistry, represents a rapid ice‐sheet withdrawal and increasingly distal sedimentation in front of the ice margin. Two erosional unconformities are observed in the eastern Mecklenburg Bight, one marking the top of the initial Baltic Ice Lake deposits and the second one indicating the end of the final Baltic Ice Lake. These unconformities join in Fehmarn Belt, where deposits of the final Baltic Ice Lake are missing due to an erosional hiatus related to a lake‐level drop during its final drainage. After this lake‐level drop, a lowstand environment represented by river deposits developed. These deposits are covered by lake marls of Yoldia age. Tilting of the early glacial lake sediments indicates a period of vertical movements prior to the onset of the Holocene. Deposits of the earliest stages of the Baltic Sea have been exposed by ongoing erosion in the Fehmarn Belt at the transition to the Mecklenburg Bight. [ABSTRACT FROM AUTHOR]

The magmatic-hydrothermal fluid evolution in the Monte Mattoni mafic complex in the Adamello batholith was reconstructed based on a combination of fluid inclusion studies (microthermometry and laser ablation inductively coupled plasma mass spectrometry microanalysis of individual fluid inclusions) and thermodynamic modeling of subsolidus fluid-mineral equilibria. The mafic complex consists of two main units, the Monte Mattoni and the Cadino gabbros, both of which show textural evidence for fluid saturation. In the Mattoni gabbro, which is crowded with equant amphibole phenocrysts forming local cumulate layers, fluid saturation was probably reached as a result of rapid magma ascent and pressure decrease. Some of the exsolved fluid phase was trapped in ocelli (miarolitic cavities of subcentimeter size) occurring in the matrix of the porphyritic gabbro. The overlying and locally transgressive Cadino gabbro consists of needle-shaped amphibole grains that crystallized together with plagioclase at the emplacement level of laterally extensive sills. The Cadino magma reached fluid saturation after progressive crystallization as shown by miarolitic cavities that formed in the center of local pegmatitic pods. Five distinct fluid inclusion types (A to E) are present as texturally and compositionally consistent assemblages in a clear relative chronology. The earlier fluid inclusion types, A to C, are three-phase aqueous-carbonic and show a decrease in salinity (from 7.9 to 5.5 wt % equivalent NaCl), coupled with a decrease in CO2 concentration, with time. The salinity in later two-phase aqueous fluid inclusion types D and E increases again (to 9.5 and 27.1 wt % equivalent NaCl), whereas the CO2 concentration drops to very low values. The Ca/Na ratio in the aqueous fluids increases and the late-stage type E fluids are concentrated calcic-sodic brines. The initial decrease in salinity and CO2 content can be explained by fluid-melt partitioning during successive stages of fluid exsolution from the magma at a minimum pressure of 150 MPa. The reversal to increasing salinity in late-stage aqueous fluids is the consequence of water-consuming subsolidus reactions of the fluid with the surrounding rocks, forming epidote, chlorite and calcite at low fluid/rock ratios. The subsolidus evolution is quantified by fluid-mineral equilibria modeling, which predicts the observed mineral transformations, the systematic variation in chemical composition of the fluids, and the decrease in their CO2 concentration as a result of calcite precipitation. Isochores constructed for the five inclusion types indicate an approximate pressure-temperature path starting with isobaric cooling for the early aqueous-carbonic fluid inclusion types at 250 MPa, followed by a substantial pressure decrease during the entrapment of increasingly saline aqueous inclusions. The late-stage calcic brine inclusions were entrapped at temperatures as low as 250°C, where brittle fracturing marks the transition to near-hydrostatic fluid pressure. The ore metal contents (Cu, Pb, Zn, W, Pb and Mn) and the S content of aqueous-carbonic fluid inclusions in the Monte Mattoni complex are comparatively low, in comparison with typically more differentiated intrusions associated with porphyry copper deposits worldwide. Low concentrations in ore-forming components, even in this mafic magma, indicate a weak endowment with ore-forming components already determined in the mantle source of the Adamello magmas. This lack of fertility for ore formation may be explained by restricted subduction metasomatism in an orogen dominated by collision and slab break-off. [ABSTRACT FROM AUTHOR]

This paper presents a practical guide to an optimized analytical procedure for the reliable quantification of trace element concentrations in fluid inclusions hosted by natural minerals, using laser ablation inductively coupled plasma mass spectrometry (ICP-MS). With the improved sensitivities of modern ICP-MS instrumentation, more stringent guidelines for cleaning and contaminant reduction become decisive in extending the limits of trace element analysis, particularly for dilute fluids and smaller inclusions investigated by highly sensitive sector field ICP-MS. We have identified three sources of contamination that limit the recording and quantification of low-count signals, namely: (1) the carrier gas quality that affects the continuous instrumental background. (2) The material and cleanliness of the ablation cell, connection tubing material, and sampler and skimmer cone, all of which may cause a falsely elevated signal during ablation. (3) Contamination of the sample surface during its preparation and from the deposition of previously ablated material, including aerosols produced during extended ablation of an ICP-MS tuning material. Contamination from these sources can overlap with the host mineral and with the fluid inclusion signal. Based on extensive test experiments, we propose a workflow that allows minimization of these contamination contributions and optimizes representative sampling and quantification of fluid inclusion data. For example, Au and S in low-density vapor-dominated inclusions may be quantified down to a few ng g−1 and a few hundred μg g−1, respectively. [ABSTRACT FROM AUTHOR]

The Apuseni-Banat-Timok-Srednogorie Late Cretaceous magmatic arc in the Carpathian-Balkan orogen formed on the European margin during closure of the Neotethys Ocean. It was subsequently deformed into a complex orocline by continental collisions. The Cu-Au mineralized arc consists of geologically distinct segments: the Apuseni, Banat, Timok, Panagyurishte, and Eastern Srednogorie segments. New U-Pb zircon ages and geochemical whole rock data for the Banat and Apuseni segments are combined with previously published data to reconstruct the original arc geometry and better constrain its tectonic evolution. Trace element and isotopic signatures of the arc magmas indicate a subduction-enriched source in all segments and variable contamination by continental crust. The magmatic arc was active for 25 Myr (~92-67 Ma). Across-arc age trends of progressively younger ages toward the inferred paleo-trench indicate gradual steepening of the subducting slab away from the upper plate European margin. This leads to asthenospheric corner flow in the overriding plate, which is recorded by decreasing 87Sr/86Sr (0.70577 to 0.70373) and increasing 143Nd/144Nd (0.51234 to 0.51264) ratios over time in some segments. The close spatial relationship between arc magmatism, large-scale shear zones, and related strike-slip sedimentary basins in the Timok and Pangyurishte segments indicates mild transtension in these central segments of the restored arc. In contrast, the Eastern Srednogorie segment underwent strong orthogonal intraarc extension. Segmental distribution of tectonic stress may account for the concentration of rich porphyry Cu deposits in the transtensional segments, where lower crustal magma storage and fractionation favored the evolution of volatile-rich magmas. [ABSTRACT FROM AUTHOR]

The Witwatersrand Basin in South Africa is one of the best-preserved records of fluvial sedimentation on an Archaean continent. The basin hosts the worlds biggest gold resource in thin pebble beds, but the process for gold enrichment is debated. Mechanical accumulation of gold particles from flowing river water is the prevailing hypothesis, yet there is evidence for hydrothermal mobilization of gold by fluids invading the metasedimentary rocks after their burial. Earth's atmosphere three billion years ago was oxygen free, but already sustained some of the oldest microbial life on land. Here I use thermodynamic modelling and mass-balance calculations to show that these conditions could have led to the chemical transport and precipitation of gold in anoxic surface waters, reconciling the evidence for fluvial deposition with evidence for hydrothermal-like chemical reactions. I suggest that the release of sulphurous gases from large volcanic eruptions created acid rain that enabled the dissolution and transport of gold in surface waters as sulphur complexes. Precipitation of the richest gold deposits could have been triggered by chemical reduction of the dissolved gold onto organic material in shallow lakes and pools. I conclude that the Witwatersrand gold could have formed only during the Archaean, after the emergence of continental life but before the rise of oxygen in the Earth's atmosphere. [ABSTRACT FROM AUTHOR]

However, it has to be noted that such scissor knife-based approach is associated with much increased accessory costs and might thus, beyond representing an attractive rescue technique after failed snare capture, be prioritized for selected individual lesions in an upfront intent. Scissor-type knife resection may be an attractive rescue and, for selected individuals, primary approach for management of difficult pedunculated colorectal lesions. As reflected by recent European guidelines, hot snare polypectomy with mechanical hemostasis techniques has been embraced as the benchmark approach in the endoscopic resection of pedunculated colorectal lesions.1 As a sine qua non, this, however, implies unproblematic snare capture of the lesion, which sometimes is complicated by overly mobile polyps and/or in sharply angulated segments with difficulties in endoscopic control of resection. [Extracted from the article]

Schwarzer, K., Bohling, B., Heinrich, C., 2014. Submarine hard-bottom substrates in the western Baltic Sea-human impact versus natural development. In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium(Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 145-150, ISSN 0749-0208. Large areas of the seafloor in the western Baltic Sea are covered by lag deposits of Pleistocene origin, consisting of gravel, stones and boulders. From about 1800-1974, commercial extraction of stones and boulders from these shallow submarine areas was carried out. These activities have fundamentally changed the sediment distribution patterns and ecological conditions of the seafloor. Based on comparisons between old analogue and modern digital sidescan sonar images and direct abrasion measurements on the seafloor by scuba divers, the development of this hard-bottom substrate was studied on a decadal to seasonal scale. We show that due to abrasion processes the amount of boulders has been increased over a 22 year period. Thus, natural regeneration of hard-bottom substrate and improvement of the ecological status of the shallow marine environment is possible. This needs to be considered in order to reestablish a 'good ecological status' as demanded by administrative guidelines like the EU Water Framework Directive and the Marine Strategy Framework Directive. [ABSTRACT FROM AUTHOR]

Different types of along-track stripe noise are common artifacts in side-scan sonar mosaics, hampering both visual image quality and automatic seabed classification attempts. In this study, a 2D Fourier domain slope filter is applied to remove stripes from side-scan sonar mosaics. This technique has the advantage of using only two simple tuning parameters, namely, the slope angle of the stripe noise, and a filtering width. Furthermore, the image processing tool presented here can be applied to non-optimally processed side-scan mosaics without the need of reprocessing the original data. The performance of the filter technique is demonstrated by two datasets in which stripe noise, including nadir stripes, has been successfully removed. To one of the filtered dataset a simple unsupervised seabed classification was then applied, leading to a much improved result with only little misclassification due to residual stripe noise. [ABSTRACT FROM AUTHOR]

Precise U–Pb geochronology, Hf isotope compositions and trace element distributions in zircons are combined in the present study to define the timing and sources of the magmatism forming the Medet porphyry copper deposit, Bulgaria. ID-TIMS U–Pb-zircon dating demonstrates that ore-bearing magmatism extended for less than 1.12 Ma. As inferred from the field relationships, it started with the intrusion of a quartz-monzodiorite at 90.59 ± 0.29 Ma followed by granodiorite porphyries at 90.47 ± 0.30 and 90.27 ± 0.60 Ma and by crosscutting aplite dykes at 90.12 ± 0.36 Ma. These units were overprinted by potassic alteration and host economic copper-(Mo–Au) mineralization. The main magmatic–hydrothermal activity ceased after that, and a later quartz-granodiorite porphyry dyke, dated at 89.26 ± 0.32 Ma, only contains an uneconomic quartz–pyrite mineralization. Assimilation of Lower Paleozoic rocks with a mantle to mantle–crust signature is characteristic of the fertile magma in the Medet deposit, as defined by positive ɛ-Hf values of the inherited zircons. The positive Ce-anomalies and the higher Eu/Eu* ratios of the zircons in the mineralized Cretaceous rocks of Medet deposit argue for crystallization from a generally more oxidized magma compared to the later quartz-granodiorite porphyry dyke. A change in paleostress conditions occurred during the intrusion of the Medet pluton and its dykes. The initial stage reveals E–W extension associated with N–S compression, whereas the younger granodiorite dyke was emplaced during subsequent N–S extension. The large-scale switch of the extensional stress regime during the mineralization was favourable for ore deposition by channelling the fluids and increasing the effective permeability. [ABSTRACT FROM AUTHOR]

The solubility of Au metal in rhyolite melt and coexisting magnetite has been determined at 800 °C, 140 MPa, and f[subO, sub2] ≈ NNO in a Au-metal saturated, sulfur-free, vapor-brine-silicate melt system. Whole crystals of magnetite suspended within quenched rhyolite glass were analyzed by LA-ICP-MS. These data yield a solubility of Au in magnetite on the order of 2 µg/g. The solubility of Au metal in rhyolite melt hosting the magnetite crystals is on the order of 500 ng/g. These data indicate a partition coefficient for Au between magnetite and melt, D[supMt/melt, subAu] ≈4. Using reasonable estimates of the mass fraction of magnetite that crystallizes in crustal magmatic systems, we modeled the proportion of Au sequestered by magnetite during fractional crystallization. We considered fractionation in two steps: the idealized derivation of a rhyolite by fractionation of basalt at depth, and the closed-system crystallization of the rhyolite in a magma chamber below the site of ore deposition. Magnetite sequesters 14-54% Au from basaltic parent melt that produces a rhyolite melt via crystal fractionation, at modal abundances of 1-5%. Less then 4% Au is sequestered from a crystallizing rhyolite melt because of low modal abundances of magnetite (<∼2%). Our experimental and model results suggest that early crystallization of magnetite can play a mitigating role in the ability of a calc-alkaline magmatic system to yield a Au-rich ore fluid. [ABSTRACT FROM AUTHOR]

The article discusses the development and evaluation of a new CHO media platform. Topics discussed include use of different CHO suspension cells in context to media development for single clone selection, optimization of cell culture media to consider cost efficiency in biopharmaceutical industry, and comparing viable cell density and integrated viable cell density of cell lines.

An abstract of the article "Growth characterization of CHO DP-12 cell lines with different high passage histories," by Christoph Heinrich and colleagues is presented.

Perfusion operation mode remains the preferred platform for production of labile biopharmaceuticals (e.g., blood factors) and is also being increasingly adopted for production of stable products (e.g., monoclonal antibodies). Regardless of the product, process development typically aims at maximizing production capacity. In this work, we investigated the impact of perfusion cultivation conditions on process productivity for production of human factor VIII (FVIII). Recombinant CHO cells were cultivated in bioreactors coupled to inclined settlers and the effects of reducing the temperature to 31°C with or without valeric acid (VA) supplementation were evaluated. Increases in cell specific productivity (qp) up to 2.4‐fold (FVIII concentration) and up to 3.0‐fold (FVIII biological activity) were obtained at 31°C with VA compared to the control at 37°C. Biological activity is the most important quality attribute for FVIII and was positively affected by mild hypothermia in combination with the chemical inducer. The low temperature conditions resulted in enhanced product transcript levels, suggesting that the higher qp is related to the increased mRNA levels. Furthermore, a high‐producer subclone was evaluated under the perfusion conditions optimized for the parental clone (31°C with VA), yielding increases in qp of 6‐fold and 15‐fold compared to the parental clone cultivated under the same condition and at 37°C, respectively. The proposed perfusion strategy enables increased product formation without increasing production costs, being potentially applicable to perfusion production of other CHO‐derived biopharmaceuticals. To the best of our knowledge, this is the first report showing the benefits of perfusion combining mild hypothermia with VA supplementation. [ABSTRACT FROM AUTHOR]

We suggest a variant of coherent anti-Stokes Raman scattering (CARS) microscopy, which is a nonlinear microscopy method that has recently proven very successful in functional imaging of living cells with vibrational contrast. Whereas existing CARS microscopy techniques involve confocal scanning, in our setup excitation and detection are performed in a wide-field (nonconfocal) geometry, similar to a combination of dark-field and epifluorescence microscopy. The use of a nanosecond laser system rather than the typically used pico- or femtosecond systems furthermore implies a high spectroscopic resolution for various Raman-active substances. We demonstrate the feasibility of the wide-field approach on test samples and discuss its prospects to become a complemental method to confocal scanning CARS microscopy. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The article discusses a study of a 62-year-old woman with cholestasis evaluated with Endoscopic retrograde cholangiopancreatography (ERCP) and been detected with double carcinoma in the biliary tract.

The article presents a study which discusses introduction of new chemically defined medium and feed for hybridoma cell lines. Topics discussed include HybriMACS CD medium developed using various research and production hybridoma cell lines from the Bielefeld University, for optimal performance of MF20 hybridoma cells the HybriMACS CD medium was supplemented with insulin, and results revealing comparison of hybridoma cell growth in HybriMACS CD medium with 12 competitor products.

The article presents a study which discusses development of a chemically defined cultivation and transfection medium for human embryonic kidney (HEK) cell lines. Topics discussed include challenges related to transfection of cells in conditioned media with reagent polyethylenimine (PEI), transfection of cells as per the protocol, chromatographic separation to evaluate the effect of cellular proteins in conditioned medium, and batch growth of HEK host cell showing maximum viable cell density.

The development of culture media and supplements for fed-batch processes is one of the most complex steps in cell culture process development. We have developed chemically defined and animal component-free media and supplements for culturing Chinese Hamster Ovary cells (CHO) and hybridoma cells, improving the production of recombinant proteins. [ABSTRACT FROM AUTHOR]

An abstract of the article "Proteomic and metabolomic characterization of CHO DP-12 cell lines with different high passage histories," by Tim Beckmann and colleagues is presented.

An abstract of the article "Utilization of multifrequency permittivity measurements in addition to biomass monitoring," by Christoph Heinrich and colleagues is presented.

An abstract of the article "Utilization of multifrequency permittivity measurements in addition to biomass monitoring," by Christoph Heinrich and colleagues is presented.