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Loss of magmatic sulfides to the mantle is posited to explain the copper deficit of evolved arc magmas and the depleted Cu/Ag ratio of the continental crust. We address the question of whether saturating sulfides may instead be mechanically entrained with rising magmas, and how this would affect their geochemical fate in the upper crust. Entrainment is plausible considering sulfide wetting properties and settling velocities relative to magma ascent velocities. Entrained sulfide increases the pressure at which magmas become saturated with respect to H-O-S fluids in the upper crust by 10-100 MPa, with the pressure difference increasing with temperature, water content, and oxidation. Bubbles are likely to nucleate on sulfide particles, allowing transfer of S and Cu from the sulfide to the fluid over a small crystallization interval without limitations by diffusion through the silicate melt. This sequence of processes gives magmatic sulfides an active role in ore metal transport and enrichment to form porphyry copper deposits, and may have global implications for crustal Cu budgets. [ABSTRACT FROM AUTHOR]

Centrifugal compressors are versatile machines that many industries employ for a wide range of different applications, including the production of highly compressed gases. During the last decades, comprehensive research was conducted on the impact of high-pressure operating conditions on the vibrational behavior of radial compressors. In various studies, acoustic modes building up in the side cavities were found to be a potential source of high cycle fatigue. Nowadays, it is well-known that an increase in gas pressure levels leads to a more pronounced fluid-structure interaction between the side cavities and the impeller resulting in a frequency shift of the acoustic and structural modes. In a recently published paper, the authors presented a generalized model which can predict this behavior. As it is not always possible to avoid operating close to or accelerating through a resonance, it is crucial to know the damping present within the system. Currently, only few publications concentrate on the damping of radial impellers. Therefore, the authors present measurement data acquired from a test rig at the University of Duisburg-Essen, which reveals the damping behavior of a disk under varying operating conditions. Two surrogate models are proposed to predict the identified damping behavior. The first one is based solely on a one-dimensional piston model and the second approach uses an enhanced version of the generalized method. Finally, the measurement data are used to validate both surrogate systems. [ABSTRACT FROM AUTHOR]

The oil and gas, chemical, and process industries employ centrifugal compressors for a wide range of applications. Due to this, the conditions under which centrifugal compressors have to operate vary significantly from case to case. Gas pipeline compressors, for example, may feature discharge pressures well over 100 bar. In other fields of application, like gas injection, which is used to enhance oil recovery, this quantity can reach considerably higher values. Here, discharge pressures over 600 bar and gas densities over 300 kg/m³ are not uncommon. During the last several decades, comprehensive research was conducted on the impact of high-pressure operating conditions on the vibrational behavior of centrifugal compressor wheels. Nowadays, it is well-known that an increase in gas pressure levels leads to a more pronounced interaction between the side cavities and the impeller, which results in a frequency shift of the acoustic and structural modes. For the safe operation of compressors, it is necessary to predict these coupled natural frequencies accurately. The state-of-the-art approach to achieve this objective is the finite element method. While this technique provides high-quality results, the simulation of acousto-mechanical systems is still a time-consuming process that incurs high computational costs. Therefore, finite element models are, in this case, not suitable for probabilistic studies, sensitivity analyses, and comprehensive simulations of the full operating range of the compressor. In 2013, Magara proposed a simplified model based on an annular plate between two cylindrical cavities to solve this problem. While this method reduces the required computational effort significantly, its use is limited to platelike impellers. The authors of this paper propose a more generalized method to overcome the challenges mentioned earlier. It uses the uncoupled structural and acoustic modes of the actual impeller and side cavities in a modal superposition to approximate the natural frequencies of the coupled acousto-mechanical system. In this way, the intended design geometries of the impeller and side cavities are considered while maintaining the advantages of Magara's model regarding the computational effort. In a numerical study, Magara's method and the generalized model are applied to different systems of increasing complexity. The investigation starts with a simple annular plate in a cylindrical cavity and ends with an actual compressor impeller. At every complexity level, the results of both approaches are compared to a finite element analysis. Moreover, measurement data of a simplified rotor in a cylindrical cavity are used to validate the numerical models. Finally, this paper concludes with a discussion of the limitations and benefits of all employed numerical methods. [ABSTRACT FROM AUTHOR]

A case study is presented of a 72-year-old female patient with familial adenomatous polyposis (FAP) who underwent Kock pouchoscopy after ileoanal pouch conversion. During the procedure, small polypoid lesions were detected and the patient underwent multiple resections for low-grade dysplasia.

The article presents a case report of an 81-year-old female who presented with chronic diarrhea and right lower quadrant pain.It mentions that the gastrointestinal endoscopy revealed villous atrophy and histopathology confirmed intraepithelial lymphocytosis. It mentions the importance of considering ARB-induced enteropathy as a differential diagnosis for gastrointestinal symptoms, emphasizing the need for awareness among clinicians and endoscopists.

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]

Alto de la Blenda is a ∼6.6-Ma intermediate-sulphidation epithermal vein system in the Farallón Negro Volcanic Complex, which also hosts the 7.1-Ma porphyry-Cu-Au deposit of Bajo de la Alumbrera. The epithermal vein system is characterised by a large extent and continuity (2 km × 400 m open to depth × 6 m maximum width) and an average gold grade of ∼8 g/t. The vein is best developed within an intrusion of a fine-grained equigranular monzonite, interpreted as the central conduit of a stratovolcano whose extrusive activity ended prior to porphyry-Cu-Au emplacement at Bajo de la Alumbrera, which is in turn cut by minor epithermal veins. The Alto de la Blenda vein consists predominantly of variably Mn-rich carbonates and quartz, with a few percent of pyrite, sphalerite, galena and other sulphide and sulphosalt minerals. Four phases of vein opening, hydrothermal mineralisation and repeated brecciation can be correlated between different vein segments. Stages 2 and 3 contain the greatest fraction of sulphide and gold. They are separated by the emplacement of a polymictic breccia containing clasts of quartz feldspar porphyry as well as basement rocks. Fluid inclusions in quartz related to stages 2 to 4 are liquid rich with 2-4 wt% NaCl(eq). They homogenise between 160 and 300 °C, with very consistent values within each assemblage. Vapour inclusions are practically absent in the epithermal vein. Quartz fragments in the polymictic breccia contain inclusions of intermediate to vapour-like density and similar low salinity (∼3 wt% NaCl(eq)), besides rare brine inclusions containing halite. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analyses of epithermal inclusions indicate high concentrations of K, Fe, As, Sb, Cs, and Pb that significantly vary within and through subsequent vein stages. Careful consideration of detection limits for individual inclusions shows high gold concentrations of ∼0.5 to 3 ppm dissolved in the ore fluid, which contains variably high sulphur concentrations in excess over Fe and other chalcophile metals. Compositional variations are interpreted to reflect cooling and contraction of lower-density magmatic fluids at depth, like those preserved in porphyry clasts that were mechanically transported up by the polymictic breccia. Ore mineral precipitation from the magmatic fluid occurred by further cooling and possibly minor mixing with surface-derived water, leading to sulphide saturation, de-sulphidation of the magmatic fluid and consequent gold precipitation. The absence of flash boiling and/or reduction by carbonaceous host rocks has led to relatively modest but constant gold grades in the carbonate-base metal-gold veins of Alto de la Blenda. [ABSTRACT FROM AUTHOR]

Serra Pelada is a world-class hydrothermal Au-Pd-Pt deposit located at the eastern border of the Amazon craton, northern Brazil. The rocks at Serra Pelada have experienced intense tropical weathering for about 70 Ma, but drill core samples preserve the primary mineralogy and hydrothermal alteration features, with extreme grades of Au, Pd and Pt individually reaching hundreds of parts per million (ppm) by weight. Mineralization at Serra Pelada occurs in hydrothermally altered metasiltstones and dolomitic metasandstones at the hinge zone of a recumbent syncline, comprising zones of hematite, chlorite-carbon, argillic, and siliceous alteration. The main hydrothermal gangue minerals are quartz, kaolinite, sericite, amesite, hematite, monazite, florencite and variable amounts of highly reflective carbonaceous matter. Hydrothermal carbon input is evident from precipitated carbon occurring along crenulation planes and veinlets associated with the precious metals. Ore and accessory minerals include a variety of sulphide, selenide, arsenide, sulphate and oxide minerals, including gold with variable metal contents, palladian gold, fischesserite, sudovikovite, sperrylite, selenian braggite, isomertieite, mertieite-II and secondary Au-Pt-Pd alloys. The composition of fischesserite varies from the ideal formula (AgAuSe) towards a more Ag-rich composition, indicating a disordered solid solution form that is stable only above 260 °C, consistent with the high thermal maturity of associated carbonaceous matter approaching graphite. Primary ore and gangue minerals at Serra Pelada comprise a suite of elements that are best transported in oxidising conditions and precipitated upon reduction. This suggests that fluid mixing between a highly oxidised (metal carrier) and a reduced fluid was a key process for high-grade noble metal precipitation at Serra Pelada. [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]

The recently discovered Biely Vrch deposit in the Western Carpathian magmatic arc is the most extreme example of a porphyry gold deposit, being practically free of copper, molybdenum or any other sulfi de minerals. Microanalytical data on fluid inclusions in quartz veinlets, including a characteristic type of banded veinlets, show that this deposit formed from nearly anhydrous Fe-K-Na-Cl salt melts containing ~10 ppm Au, coexisting with hydrous vapor of very low density. This exceptional fluid evolution required an Fe-rich dioritic source magma that was emplaced at shallow subvolcanic depth (<3.5 km), directly exsolving a hypersaline liquid and magmatic vapor at high temperature (~850 °C). During ascent to the level of the porphyry intrusion (0.5-1 km), fluid expansion at high temperature but low pressure led to halite precipitation and further water loss to the vapor, generating an increasingly Fe-K-rich salt melt that transported high concentrations of Au but negligible Cu into the fractured porphyry stock. The low sulfur fugacity resulting from fluid expansion suppressed precipitation of sulfide, explaining the goldonly enrichment in this globally recurring but rare type of gold ore. [ABSTRACT FROM AUTHOR]

Recent experimental studies have raised concerns that Cu concentrations in quartz-hosted fluid inclusions from magmatic–hydrothermal ore deposits do not represent pristine concentrations in the trapped fluids, but are modified by post-entrapment diffusional exchange through the host quartz. New microanalyses of fluid inclusions hosted in topaz show significantly lower Cu concentrations in vapor inclusions, compared to otherwise identical inclusions hosted by coexisting quartz, whereas coeval brine (hypersaline liquid) inclusions are very similar independent of host mineral in one sample. Sulfur is present as a major component in all vapor inclusions, as in most porphyry-related vapor inclusions, and Cu never exceeds S, but commonly matches the S content at a molar ratio of Cu:S ⩽ 2 in vapor inclusions hosted by quartz. Univalent ions with a radius smaller than ∼1 Å are known to diffuse rapidly through the channels of the quartz structure, parallel to its crystallographic c axis. Since only Cu concentrations differ between topaz- and quartz-hosted inclusions, we hypothesize that Cu + and H + re-equilibrate by diffusional ion exchange through these channels, while all other element concentrations remain essentially unchanged. A thermodynamic model considering charge-balanced Cu + H + exchange and diffusive H 2 re-equilibration of an initially Cu-poor but S-rich vapor inclusion with a typical rock-buffered fluid environment outside the host crystal demonstrates a strong chemical driving force for Cu + to migrate from the surrounding rock into the fluid inclusion during cooling of the system. The driving force for Cu diffusion, against the gradient in total Cu concentration, is the abundant H + liberated inside the inclusion by dissociation of HCl and particularly by the precipitation of CuFeS 2 by reaction with the initially trapped H 2 S and/or SO 2 . Gold is not only a much larger ion, but is subject to an opposing driving force, suggesting that high concentrations of this larger ion analyzed in vapor inclusions probably represent true gold concentrations in magmatic–hydrothermal vapor. These findings imply that brine–vapor separation in porphyry deposits does not cause selective Cu transfer to the vapor, but is more likely to destabilize Cu complexes and promote copper ore deposition during decompression and unmixing of the two fluid phases. By contrast, Au may be selectively transferred into the vapor phase, allowing its transport through the deeper porphyry copper deposits to form epithermal gold deposits closer to the earth’s surface. [ABSTRACT FROM AUTHOR]

The process responsible for the gold mineralization in the Witwatersrand Basin, South Africa, remains controversial; the debate is between a detrital placer enrichment in laterally extensive conglomerate layers, and hydrothermal introduction by metamorphic fluids long after sedimentation. While textural and geochronological data may be ambiguous, a first-order geological observation severely delimits the mechanism and timing of gold emplacement. The individual gold reefs are cut and displaced by numerous mafic dikes, which, based on geochemical data presented here, are feeders to flood basalts immediately overlying the Witwatersrand. The displacements preclude fracture-controlled fluid focusing over tens of kilometers along a single conglomerate horizon during or after regional metamorphism. Instead, basin-scale gold enrichment occurred during sedimentation or early diagenesis, well before local redistribution by metamorphic fluids. [ABSTRACT FROM AUTHOR]

Abstract: The massive sulfide deposits of the Iberian Pyrite Belt are interbedded with felsic volcanic rocks and shale, and underlain by several thousand meters of siliciclastic sedimentary rocks known as the PQ Group. Isotope geochemistry and regional geology are both consistent with equilibration of the ore-forming fluids with the PQ Group, prior to ore deposition near the former seafloor. The average Cu:Zn:Pb ratio of the PQ Group rocks (ca. 26:55:19) is similar to the weighted average of all the massive sulfide orebodies combined (ca. 25:52:23). The genetic relationship between massive sulfide deposits and a siliciclastic sedimentary metal source is explained here by a thermodynamic model, proposing that mildly reducing redox conditions imposed by equilibration with the sedimentary rocks are most critical for the formation of an effective ore-forming fluid. Relatively metal-rich but organic-poor pyrite-bearing shale undergoing dewatering of saline pore fluids is an effective source for the generation of sulfur-deficient but relatively iron and base metal-rich brines. Thus, we propose that the giant deposits of the Iberian Pyrite Belt owe their existence not to exceptionally metal-enriched (e.g., magmatic) fluids, but to the existence of a fairly ordinary but large metal source in reactive siliciclastic sediments, combined with an underlying igneous heat source and a particularly efficient mechanism of sulfide precipitation by mixing with H2S-rich fluids at or near the seafloor. Essentially similar mineral equilibria are imposed when saline fluids are buffered by typical continental basement rocks. Leaching of retrograde minerals and possibly residual salts from their magmatic or metamorphic prehistory is expected to generate similar, variably metal-rich but relatively sulfide-deficient fluids. Thus, the existence of mildly reducing rocks can be the dominant chemical control in the source of fluids generating many volcanogenic, Irish-type or sedex deposits, many of which are known to precipitate their metal load in response to biogenic sulfide addition at the ore deposition site. [Copyright &y& Elsevier]

Abstract: Realistic simulations of fluid flow in geologic systems have severely been hampered by the lack of a consistent formulation for fluid properties for binary salt–water fluids over the temperature–pressure–composition ranges encountered in the Earth’s crust. As the first of two companion studies, a set of correlations describing the phase stability relations in the system H2O–NaCl is developed. Pure water is described by the IAPS-84 equation of state. New correlations comprise the vapor pressure of halite and molten NaCl, the NaCl melting curve, the composition of halite-saturated liquid and vapor, the pressure of vapor+liquid+halite coexistence, the temperature–pressure and temperature–composition relations for the critical curve, and the compositions of liquid and vapor on the vapor+liquid coexistence surface. The correlations yield accurate values for temperatures from 0 to 1000°C, pressures from 0 to 5000bar, and compositions from 0 to 1 X NaCl (mole fraction of NaCl). To facilitate their use in fluid flow simulations, the correlations are entirely formulated as functions of temperature, pressure and composition. [Copyright &y& Elsevier]

Fluid-phase stability relations combined with thermodynamic modeling using fluid-inclusion analyses and new gold-solubility experiments lead to an integrated geological interpretation linking epithermal gold mineralization and porphyry-style ore formation to the cooling of hydrous magma chambers. The essential chemical requirement for gold transport to low temperatures is an initial excess of sulfide over Fe in the magmatic fluid, which is best achieved by condensing out Fe-rich brine from a buoyant, low- to medium-salinity vapor enriched in volatile S. This vapor can contract directly to an aqueous liquid, by cooling at elevated pressure above the critical curve of the salt-water fluid system. Physical and chemical conditions are matched when magmatic fluid is released through a gradually downward-retracting interface of crystallizing magma beneath a porphyry stock, predicting the consistent zoning and overprinting relations of alteration and mineralization observed in magmatic hydrothermal systems. [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.

Large quartz pebbles erupted with the Escorial ignimbrite provide insight into the late-magmatic evolution of the shallow, cooling magmatic-hydrothermal system below the Cerro Escorial volcano of the Southern Central Volcanic Zone in the Argentine Andes. The ignimbrite is of relatively small volume, crystal-rich, dacitic in composition, and not particularly water-rich, as amphibole is absent. Eruption temperature was estimated to be close to 850 °C. The quartz pebbles provide insight into the magmatic-hydrothermal transition beneath the volcano. Based on textures, trace element composition (analyzed by laser-ablation inductively-coupled plasma mass spectrometry), and inclusion content, the pebbles can be separated into pegmatite-like megacrysts and lower-temperature, epithermal microcrystalline quartz. Both types are distinct from magmatic phenocrysts present in porphyritic clasts ejected by the ignimbrite. The megacrysts show a wide range of trace element concentrations, with elevated Al concentrations and Al/Ti and Ge/Ti ratios compared to quartz phenocrysts. Although some contamination by submicroscopic inclusions and cooling to near-solidus temperatures may perturb the signal in some cases, the range of trace element concentrations in quartz crystals from this system may reflect a change in crystallization conditions from initial precipitation from typical evolved silicate melt to fast growth from residual melt and/or fluid in pegmatitic pockets or coarse-grained hydrothermal "veins" at locally variable precipitation conditions. Abundant primary and secondary silicate melt inclusions and a variety of secondary fluid inclusions are present within the megacrysts. In particular, brine inclusions are densely packed with salt crystals, sometimes anhydrite and/or a silicate crystal, but no visible liquid at room temperature, and co-existing vapor inclusions are of very low density. Heating experiments of brine inclusions reveal last salt and vapor bubble dissolution temperatures around 600–700 °C, but an immiscible silicate melt surrounding the homogenized salt globule remains even at unreasonably high temperature. The co-existence of silicate melt and fluid inclusions reinforces the magmatic nature of the fluids, while boiling trails of brine (with Cu concentrations of several percent) and vapor point to relatively low pressures (<100 MPa). • Ejected quartz reveals magmatic-hydrothermal transition below arc volcano. • Texturally and compositionally distinct, pegmatite-like quartz megacrysts. • Late-stage high-temperature magmatic brine very rich in copper. [ABSTRACT FROM AUTHOR]

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.

• We present a model of magmatic fluid transport in and out of cooling hydrous magmas. • The depth and water content of magma chambers control their outgassing patterns. • Some scenarios lead to focused outgassing, a requirement for economic ore deposits. Volatile outgassing from hydrous magma intrusions emplaced and cooling in the Earth's upper crust is key to a number of geologic processes including volcanic eruptions and ore deposition, yet the physical interactions between production, storage and transport of a magmatic volatile phase within magmatic intrusions and their large-scale thermal evolution have remained elusive. We performed numerical simulations of aqueous volatile transport in generic magma chambers as they crystallize in response to conductive and convective cooling and thereby transition from a crystal - volatile - melt suspension to a mush and eventually to a rigid rock. We used simplified but realistic material properties based on published phase equilibrium experiments, published grain-scale modeling results and general geological constraints. We found that the intrusion depth and water content exert decisive control on the rates and mechanisms of intrusion outgassing. Above a critical volatile content, highly permeable capillary tubes develop in crystal mush regions with intermediate crystal volume fractions (∼ 0.5 to 0.7), and such grain-scale tubes provide rapid intrusion-scale degassing paths. These tubes are located in a ring-like mush region inside the intrusion, allowing strongly lateral flow and focusing towards the top of the intrusion. If the water content of the magma is close to saturation at the time of emplacement (5 to 6 wt% H 2 O) and the depth of the magma chamber roof is at least 4 km deep, initially distributed breakthrough points may coalesce to a single area of fluid release. Large-scale intrusion geometry determines this location of focused fluid release, and cooling rate and size of the intrusion determine overall fluid flux. Feedbacks between local hydrofracturing and heat advection break up the focused fluid expulsion into many short-lived pulses. These conditions for large-scale fluid focusing favor the formation of porphyry copper deposits, but might also trigger caldera-forming ignimbrite eruptions. [ABSTRACT FROM AUTHOR]

• The Serra Pelada deposit was formed by mixing between a reduced and an oxidizing, metal-carrier hydrothermal fluid. • Gold contents of the mineralizing fluids are between 50 and 500 ppb. • Pressure and temperature for the mineralization are estimated at 250–270 °C and 1.2–1.7 kbar. Serra Pelada is a high-grade hydrothermal Au-Pd-Pt deposit within the Carajás mineral province, eastern Amazon craton, which shows an exceptional metal enrichment at carbon-enriched hosted ores (>1000's ppm Au + Pt + Pd). The main orebody is structurally hosted at the hinge of a recumbent syncline, consisting of dolomitic metasandstones at the outer part of the fold, a layer of carbonaceous metasiltstone in which most orebodies are located, and red siltstone in the core of the fold. Distal hydrothermal alteration comprises spatially separated chlorite – carbon (reduced) and hematite (oxidized) alteration zones. The mineralized zones include silicification and argillic (carbon- kaolinite-, and hematite-rich) alteration zones. Fluid inclusions hosted by quartz and dolomite crystals from distal alteration zones and silicified portions within the mineralized zone record a wide range of salinity (5–22 wt% NaCl eqv.) but relatively constant homogenization temperatures (170 ± 25 °C). Pressure and temperature estimations based in the fluid inclusion microthermometry and selenide thermometry constrain the formation of the deposit at 250–270 °C and 1.2–1.7 kbar. Element concentrations of alkali metals, Pb, Cs and to a lesser extent Ba correlate with salinity, whereas redox-sensitive elements including U and Ce vary widely. Gold concentrations from 50 to 500 ppb detected in some inclusions are consistent with the highly oxidizing conditions defined by selenide mineralogy. The presence of uranium and gold within fluid inclusions of the distal hematite alteration zone confirms the oxidizing, metal carrier fluids. The occurrence of hydrothermally precipitated carbon implies that a reducing CH 4 -bearing fluid was also present, and the structural relationships suggest that mixing between this reducing fluid (and interaction with carbon-upgraded rocks) with an acidic, oxidizing and metal-carrying fluids was the main process driving ore metal precipitation. The genesis of the Serra Pelada Au–Pd-Pt deposit shows similarities with sediment-hosted copper deposits and unconformity-related U ± Au ± PGE deposits, having in common the downflow of highly oxidizing fluids into the hydrothermal domain of the Earth's upper crust. Major differences in metal proportions of these broad classes of ore deposits and other sediment-hosted systems in different ore provinces are primarily caused by differences in source rocks available for oxidative leaching and variations in the geometry of the hydrothermal system. [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]

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 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.

• Fluid inclusions from juvenile clasts record pre-eruptive pressure variations in the magma reservoir. • Most metals get enriched in the exsolving single-phase fluid compared to the rhyolitic melt. • Rapidly erupted fluid inclusions escaped post-entrapment modifications seen in slowly cooled samples from ore deposits. Pre- to syn-eruptive fluids released by the magmatic system forming the non-welded rhyolitic Kos Plateau Tuff ignimbrite, Greece, were characterized using fluid inclusions entrapped in quartz from granitic clasts entrained from the roof or walls of the feeding magma reservoir. This fluid was initially of intermediate density and relatively low salinity (3–11 wt% NaCl equivalent). Following significant pressure drop(s), it separated into immiscible brine and CO 2 -bearing vapor occurring as texturally less mature inclusions. The transition from single- to two-phase-fluid occurred at magmatic conditions, as supported by high fluid inclusion homogenization temperatures (ca. 700 °C) and simultaneous trapping of fluid inclusions with silicate melt inclusions. The large recorded pressure drop together with texturally immature fluid inclusion shapes suggests a possible direct relation between the fluid phase change and the incipient 161 ka caldera-forming eruption. All inclusion types occur predominantly along (pseudo-) secondary trails in the granitic clasts, indicating efficient entrapment in microfractures formed at high crystallinity, as attested to by elevated concentrations of incompatible elements in the silicate melt inclusions. Fast quenching of the inclusions due to eruption prevented significant post-entrapment chemical modification, providing pristine samples of magmatic fluid compositions. Element concentrations in co-existing fluids and silicate melt were analyzed using laser ablation inductively-coupled plasma mass spectrometry and compared in view of element transporting capabilities and magmatic-hydrothermal ore formation. Economically important metals such as Cu, Zn, Mo, and W were extracted from the silicate melt by the fluid. In particular, Cu concentrations in the single-phase fluid in the range of 100–500 ppm agree well with previous experimental and modeling studies and, therefore, represent values expected for primary magmatic fluids. Most elements got further enriched in the brine upon phase separation, except Li, B, and As, which may have contributed significantly also to the vapor phase. Considering the similarity between vapor and intermediate-density fluid in terms of salinity, however, the metal-enriched brine phase only comprised a minor fraction of the bulk fluid. [ABSTRACT FROM AUTHOR]

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.

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.

The article focuses on the process of gold mineralization and ore formation in the Earth's crust. There are different procedures for extracting valuable metals. Metal ores are formed when the water-rich fluids circulate through large volumes of the Earth's crust by selective enrichment. Gold mineralization is associated with magmatic processes. There are several issues related to magmatic-hydrothermal ore formation. Researchers are analyzing samples of magmatic fluids that contain gold deposits. The fluids were formed at the Ladolam Mine on the Lihir Islands, Papua New Guinea. The Ladolam gold deposit was formed from Luise Volcano.

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]

Aiming at increasing productivity in mammalian cell processes, mild hypothermia and supplementation with short-chain fatty acids have been investigated in literature, but usually separately. The combined effects of butyric acid and hypothermia were investigated in a few studies, but despite the lower cytotoxicity of valeric acid no reports were found on its use under low temperatures. In this work, DOE was used to compare supplementation with both butyrate and valerate at 31, 34 and 37 °C to enhance recombinant protein productivity in a CHO cell process. Due to the promising results obtained with valerate, this fatty acid was further investigated. According to the results obtained, 1 mM valeric acid at 31 °C enables high cell viabilities, higher product titres and increases cell specific productivity (q p ) by approximately 4-fold. Cell cycle analysis showed that at 31 °C, especially with valerate, a higher percentage of cells was in G 0 + G 1 phase. Overall, an inverse relation between q p and cell proliferation state [S/(G 0 + G 1 ) ratio] was observed. To our knowledge, this is the first work describing the effects of valeric acid under mild hypothermia on CHO cell cultivations. The results provide a promising tool to increase q p under lower proliferation rates, which can be very useful to develop robust high-cell-density, high-productivity perfusion processes. [ABSTRACT FROM AUTHOR]

The formation of world class porphyry copper deposits reflect magmatic processes that take place in a deeper and much larger underlying magmatic system, which provides the source of porphyry magmas, as well as metal and sulphur-charged mineralising fluids. Reading the geochemical record of this large magmatic source region, as well as constraining the time-scales for creating a much smaller porphyry copper deposit, are critical in order to fully understand and quantify the processes that lead to metal concentration within these valuable mineral deposits. This study focuses on the Bajo de la Alumbrera porphyry copper deposit in Northwest Argentina. The deposit is centred on a dacitic porphyry intrusive stock that was mineralised by several pulses of porphyry magma emplacement and hydrothermal fluid injections. To constrain the duration of ore formation, we dated zircons from four porphyry intrusions, including pre-, syn- and post-mineralisation porphyries based on intersection relations between successive intrusion and vein generations, using high precision CA-ID-TIMS. Based on the youngest assemblages of zircon grains, which overlap within analytical error, all four intrusions were emplaced within 29 ka, which places an upper limit on the total duration of hydrothermal mineralisation. Re/Os dating of hydrothermal molybdenite fully overlaps with this high-precision age bracket. However, all four porphyries contain zircon antecrysts which record protracted zircon crystallisation during the ∼200 ka preceding the emplacement of the porphyries. Zircon trace element variations, Ti-in-zircon temperatures, and Hf isotopic compositions indicate that the four porphyry magmas record a common geochemical and thermal history, and that the four intrusions were derived from the same upper-crustal magma chamber. Trace element zoning within single zircon crystals confirms a fractional crystallisation trend dominated by titanite and apatite crystallisation. However, zircon cathodoluminescence imaging reveals the presence of intermediate low luminescent (dark) growth zones in many crystals from all intrusions, characterised by anomalously high Th, U and REE concentrations and transient excursions in trace element ratios. A return to the same fractionation trend after this excursion excludes external compositional forcing such as magma mixing. Instead we interpret the “dark-zones” to record zircon crystallisation during a transient event of rapid growth that resulted from mafic magma injection into the base of the magma chamber, releasing a CO 2 -rich vapour phase into the dacitic crystal mush. We propose that this vapour phase then migrated upwards to the apical part of the magma chamber from where it was expelled, together with successive batches of magma, to form the porphyry copper deposit within a short time-span of less than a few 10,000 years. The short duration of host rock emplacement, hydrothermal alteration and mineralisation presented in this study provides critical constraints on fluid storage in magma chambers and the genesis of large porphyry copper deposits. [ABSTRACT FROM AUTHOR]

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]

The Cu-Au deposit of Bor (Serbia) represents a continuum of mineralization styles, from porphyry-style ore occurring in quartz-magnetite-chalcopyrite veins and chalcopyrite disseminations to high-sulfidation epithermal Cu-Au ores in pyrite-chalcopyrite and anhydrite-sulfide veins. Decisive for the great economic importance of Bor is the presence of exceptionally rich high-sulfidation massive sulfide orebodies, composed of pyrite + covellite + chalcocite/digenite and minor anhydrite and enargite. They form irregular bodies measuring 0.5–10 million tons of ore grading up to 7% Cu, hosted by andesites and surrounded by intense argillic alteration. This study focuses on a small but rich underground orebody mined out recently, where limited drillcore is preserved for quantitative geochemical study. This paper documents the vein relationships within the deep porphyry-style orebody of Borska Reka, the transitional porphyry-epithermal veins, and the overlying and laterally surrounding epithermal massive sulfides of the Bor deposit. Geological observations indicate that the formation of massive sulfide orebodies concludes the ore formation. Mass balance calculations, recast into geologically realistic bulk fluid-rock reactions, confirm textural evidence that near-isovolumetric replacement of andesite host rocks is the dominant formation mechanism of massive sulfide orebodies at Bor, whereby all lithophile elements including Si are dissolved and only Ti stays relatively immobile. While net volume changes for individual mineralization styles within the massive sulfide orebody vary from − 16% volume loss to + 127% volume gain, overall volume change for the whole massive sulfide orebody was probably slightly negative. Brecciation is important only as means of creating channelways for reactive fluid that turns the andesite protolith into massive sulfide, whereas net breccia infill occurred only locally. [ABSTRACT FROM AUTHOR]

Abstract: Land–ocean interactions in the coastal zone are severely influenced by tidal processes. In regions of high sediment discharge like the Mekong River Delta in southern Vietnam, these processes are even more significant. Three cruises in 2006, 2007 and 2008 were carried out to investigate the sediment suspension and their spatial distribution. Additionally, we investigated the influence of the tidal currents in relation to the suspended sediment. Therefore, all cruises took place during the inter-monsoon season between March and May where wave and wind influences are not dominant in contrast to the summer monsoon (May to early October) and winter monsoon season (November to early March). Suspended sediment concentrations (SSCs) in the particle-size range between 2.5 and 500μm were measured with an LISST-instrument (Laser In Situ Scattering and Transmissiometry). Current velocities and directions were recorded with an Acoustic Doppler Current Profiler (ADCP). Additionally, data of different tidal gauge stations in the Mekong River Delta were correlated and compared to the mixed semidiurnal–diurnal tidal cycle. Our results show significant areas of SSCs greater than 25μl/l in the Mekong River branches and its subaqueous delta during the inter-monsoon season. 20% of all measured SSCs in the subaqueous Mekong Delta exceed 100μl/l. Highest concentrations occur close to the seabed. SSCs decrease at the transition to the open shelf. The shelf region contains only low suspension loads, especially on the south-eastern shelf (99% of all samples <25μl/l). However, in the southern shelf region around Ca Mau Cape the suspension load is also higher (>25μl/l) close to the seabed in water depths of 20–25m. Two surveys lasting 25h each were performed on mooring stations in 12m (Mooring 1) and 26m (Mooring 2) water depth and located 3.2km apart on the subaqueous delta slope. Similar patterns of SSC over time show that concentrations of suspension load correlate with the tidal current velocities. High tidal current velocities of up to 0.6m/s near the sea bottom generate increasing SSCs of more than 25μl/l in the water column. Additionally a significant trend of decreasing SSC from the near-seabed to the upper part of the water column can be observed. In terms of sediment transport the ebb phase dominates the tidal cycle by its higher tidal current velocities but the flood phase has the longer duration. The switch of the tidal current direction from ebb to flood phase occurs rapidly against which the change from flood to ebb phase requires up to 3h. This leads to an asymmetry of the tidal ellipses and may cause a net-sediment transport from the shelf into the subaqueous Mekong Delta. In the subaqueous Mekong Delta and adjacent shelf, seven transects show similar patterns of SSCs dependent to the tidal phase. A hypopycnal sediment plume from the subaqueous Mekong Delta into the shelf region was not observed. Our results imply that resuspension by tidal currents dominates the sediment transport in the subaqueous Mekong Delta and adjacent shelf regions during the inter-monsoon season. [Copyright &y& Elsevier]

Abstract: The global supply of Mo and much of Cu and Au comes from porphyry-type ore deposits associated with hydrous magmas of broadly calc-alkaline composition, thought to be generated by contemporaneous subduction zone processes. Molybdenum is generally considered to be derived from the continental crust while Cu and Au are sourced in the mantle wedge above subducting slabs. Here we show that neither contemporaneous subduction nor derivation of Mo from crustal sources is required to explain the genesis of porphyry–Cu–Mo–Au deposits on Proterozoic lithosphere in the eastern Rocky Mountains. Uniform Pb isotope ratios measured by LA-MC-ICP-MS in individual fluid inclusions from distinct Cu–Au and later Mo ore-forming stages at Bingham Canyon, USA, demonstrate a common metal source. Uranogenic Pb isotope ratios are particularly non-radiogenic (17.494< 206Pb/204Pb<17.534; 15.553< 207Pb/204Pb<15.588) and plot to the left of the geochron and above the mantle Pb evolution line. In 207Pb/206Pb vs. 208Pb/206Pb space, the fluid Pb isotope data cluster at the non-radiogenic end of a mixing line described by >80 feldspar data from igneous rocks intimately associated with magmatic-hydrothermal ore formation, which extends to modern depleted mantle or upper crust. Forward Monte Carlo simulations require three events for the U–Th–Pb isotope evolution of the fluid: (1) Late Archean formation of enriched crust is followed by (2) preferential extraction of Pb from this aged crust into a subduction fluid characterized by drastically reduced U/Pb that metasomatized lithospheric mantle at ∼1.8Ga. This mantle reservoir then evolved to produce the retarded uranogenic Pb isotope signatures of the Bingham Canyon Cu–Mo–Au deposit in the Cenozoic (3). Similarly retarded uranogenic Pb isotope data characterize the giant porphyry–Mo and Climax-type Mo deposits of Henderson, Questa, Butte, and SE Arizona that occur in Proterozoic sutures of the central and eastern Rocky Mountains. We propose that Cenozoic melting of subcontinental lithospheric mantle metasomatized by subduction fluids during early Proterozoic amalgamation of terranes to the Wyoming Craton provides the metal endowment and subduction flavour to the giant magmatic-hydrothermal Cu–Mo–Au ore deposits in western North America, which together constitute the world''s major molybdenum ore province. [Copyright &y& Elsevier]

Abstract: Essential resources of many rare metals including copper, zinc, molybdenum, silver and gold occur in natural sulfide mineral deposits. Understanding the origin of these metal resources has been limited by a lack of data about the geochemistry of sulfur, the most important and abundant element of ore deposits. We report the first directly measured sulfur concentrations in high-temperature fluids, together with their ore-metal contents, using a new method for sulfur quantification in fluid inclusions by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Co-genetic brine and vapor inclusions from magmatic–hydrothermal ore deposits and granitic intrusions show an excess of sulfur over ore metals, as required for efficient ore-mineral precipitation. The results demonstrate that S, Cu and Au are highly enriched in vapor-like magmatic fluids, implying that such low-salinity fluids are the key agent for the formation of porphyry copper and epithermal gold deposits. [Copyright &y& Elsevier]

Abstract: Experiments were conducted to determine the extent and mechanism by which the composition of quartz-hosted silicate melt inclusions (SMI) and aqueous fluid inclusions (FI) can undergo post-entrapment modification via diffusion. Quartz slabs containing assemblages of SMI and FI were reacted with synthetic HCl bearing and metalliferous aqueous fluids at T =500–720°C and P =150–200MPa. SMI from the single inclusion assemblages were analyzed by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) and electron probe microanalysis (EPMA) before and after the experiments. Analyses revealed that rapid diffusion of the univalent cations Na+, Li+, Ag+, Cu+ and H+ occurred through the quartz from the surroundings, resulting in significant changes in the concentrations of these elements in the inclusions. Concentrations of other elements with an effective ionic radius larger than that of Ag+, or multiple valence states were not modified in the inclusions during the experiments. Our results warn inclusion‘‘ researchers that the interpretation of Na, Li, Cu and Ag concentrations from quartz-hosted SMI and FI should be treated critically. [Copyright &y& Elsevier]

Abstract: The Rhodope Massif in southern Bulgaria and northern Greece hosts a range of Pb–Zn–Ag, Cu–Mo and Au–Ag deposits in high-grade metamorphic, continental sedimentary and igneous rocks. Following a protracted thrusting history as part of the Alpine–Himalayan collision, major late orogenic extension led to the formation of metamorphic core complexes, block faulting, sedimentary basin formation, acid to basic magmatism and hydrothermal activity within a relatively short period of time during the Early Tertiary. Large vein and carbonate replacement Pb–Zn deposits hosted by high-grade metamorphic rocks in the Central Rhodopean Dome (e.g., the Madan ore field) are spatially associated with low-angle detachment faults as well as local silicic dyke swarms and/or ignimbrites. Ore formation is essentially synchronous with post-extensional dome uplift and magmatism, which has a dominant crustal magma component according to Pb and Sr isotope data. Intermediate- and high-sulphidation Pb–Zn–Ag–Au deposits and minor porphyry Cu–Mo mineralization in the Eastern Rhodopes are predominantly hosted by veins in shoshonitic to high-K calc-alkaline volcanic rocks of closely similar age. Base-metal-poor, high-grade gold deposits of low sulphidation character occurring in continental sedimentary rocks of synextensional basins (e.g., Ada Tepe) show a close spatial and temporal relation to detachment faulting prior and during metamorphic core complex formation. Their formation predates local magmatism but may involve fluids from deep mantle magmas. The change in geochemical signatures of Palaeogene magmatic rocks, from predominantly silicic types in the Central Rhodopes to strongly fractionated shoshonitic (Bulgaria) to calc-alkaline and high-K calc-alkaline (Greece) magmas in the Eastern Rhodopes, coincides with the enrichment in Cu and Au relative to Pb and Zn of the associated ore deposits. This trend also correlates with a decrease in the radiogenic Pb and Sr isotope components of the magmatic rocks from west to east, reflecting a reduced crustal contamination of mantle magmas, which in turn correlates with a decreasing crustal thickness that can be observed today. Hydrogen and oxygen isotopic compositions of the related hydrothermal systems show a concomitant increase of magmatic relative to meteoric fluids, from the Pb–Zn–Ag deposits of the Central Rhodopes to the magmatic rock-hosted polymetallic gold deposits of the Eastern Rhodopes. [Copyright &y& Elsevier]

Quantitative microanalysis of entire silicate and sulfide melt inclusions by Excimer Laser-ablation inductively-coupled-plasma mass-spectrometry (LA-IC- PMS) has been applied to extrusive and shallow intrusive rocks from the andesitic Farallón Negro Volcanic Complex (northwestern Argentina). Silicate melts are trapped in pyroxene, amphibole, plagioclase and quartz, and sulfide melts are trapped in amphibole. Details of the analytical approach and the quantification procedure are given and the results are evaluated to test the accuracy of the technique and the validity of the interpretation of analytical signals. Similar compositions of silicate melt inclusions trapped in truly co-precipitating minerals show that the quantification approach of melt inclusion compositions from LA-ICPMS signals through an internal standard is valid. This correspondence also shows that melt inclusions investigated in this study are not significantly influenced by the boundary layer around a growing crystal or by post-entrapment modifications. Post-entrapment diffusive re-equilibration only affected the Fe and Mg content of melt inclusions in mafic phases. Thus, melt inclusions are representative samples of the melt from which the host mineral crystallized, with regard to most major and trace elements. Sulfide melt inclusions (present as pyrrhotite with exsolution of Au and Cu in phases separated during cooling) were analyzed for their bulk Fe, Cu and Au content, and the abundance of these elements was quantified using a silicate glass as external standard. The validity of this calibration was tested by comparing electron microprobe analyses of Fe, Cu, Ni and Co in homogeneous sulfide minerals with LA-ICPMS results. Identical results within calculated uncertainty (one standard deviation of five to nine analyses, mostly between 1 and 5 wt% RSD) demonstrate that for these elements, measured element ratios are independent of the matrix using our analytical setup. [ABSTRACT FROM AUTHOR]

Current techniques for the quantification of melt inclusion chemistry require that inclusions are compositionally homogeneous and that post-entrapment devitrification or crystallization onto the inclusion walls could be reversed by appropriate re-melting. Laser-ablation ICP-MS provides a technique by which single heterogeneous inclusions can be analysed, thus avoiding the above prerequisites. Because host mineral is ablated with the inclusion, quantification of the melt composition necessitates deconvolution of the mixed signal by an internal standard. This can be obtained in various ways, including: (1) a fixed, pre-determined, concentration of a given element in the melt; (2) whole rock differentiation trends in a given igneous suite; (3) a constant, measured, distribution coefficient between the host and the inclusion melt and (4) determination of the volume ratios between the inclusion and total ablated volume. These four approaches were tested on a large set of cogenetic inclusions from a single plagioclase crystal in a rhyodacitic intrusion. Results suggest that quantification through whole rock differentiation trends is the most widely applicable, the most accurate and the least time-consuming technique, provided that the resulting data are critically interpreted with regard to the underlying assumptions. Uncertainties on the calculated element concentrations in the inclusions depend on the mass ratio between the melt inclusion and the host for a given ablation. They are of the order of 10% if the melt inclusion contributes more than 20% to the bulk analytical signal of a particular element. Calculated limits of detection for spherical 10 μm melt inclusions are of the order of a few ppm for elements strongly enriched in the melt relative to the host crystal. Concentrations in the melt inclusions can be determined even for elements enriched in the host mineral, but in this case uncertainties and calculated limits of detection increase with the concentration in the host. The uncertainty on the melt composition from a set of cogenetic inclusions can be commonly decreased by calculating of an uncertainty-weighted average of the concentration and their uncertainty. [Copyright &y& Elsevier]

Presents research which quantified the physical and chemical mechanism of ore precipitation in the Yankee Lode tin deposit, Mole Granite, Australia. Trace-element microanalysis of fluid inclusions; Use of laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS); Tin precipitation; Magmatic vapor phase transporting copper and boron.

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]

Microanalysis of major and trace elements in sulfide and silicate melt inclusions by laser-ablation inductively coupled plasma mass spectrometry indicates a direct link between a magmatic sulfide liquid and the composition of porphyry-type ore deposits. Copper (Cu), gold (Au), and iron (Fe) are first concentrated in a sulfide melt during magmatic evolution and then released to an ore-forming hydrothermal fluid exsolved late in the history of a magma chamber. The composition of sulfide liquids depends on the initial composition and source of the magma, but it also changes during the evolution of the magma in the crust. Magmatic sulfide melts may exert the dominant direct control on the economic metal ratios of porphyry-type ore deposits. [ABSTRACT FROM AUTHOR]

Carbon dioxide is one of the most abundant volatile components in magmas after H 2 O along with S and Cl, which are of great importance to the extraction of trace metals into magmatic-hydrothermal fluids and ore minerals. Yet the effect of CO 2 on the partition coefficients of chlorine between water-rich fluid and melt (i.e. the ratio of mass Cl concentrations in the corresponding phase; [ D Cl fluid/melt ]) is still poorly constrained. We conducted a set of experiments to constrain the effect of CO 2 on D Cl fluid/melt by equilibrating felsic silicate melts with aqueous NaCl-bearing fluids while varying the concentration of CO 2 at pressures between 120 and 300 MPa and temperatures of 850 and 1000 °C. The starting melt was synthetized as a glass in the ternary albite-quartz-Al 2 O 3 system to ensure the only significant metal chloride species in the equilibrium fluid phase was NaCl. The results demonstrate that D Cl fluid/melt values increase with the concentration of Cl in the fluid phase and the silicate melt. The addition of CO 2 into aqueous metal chloride-bearing fluids induces a pronounced drop in D Cl fluid/melt , the extent of which is only weakly affected by pressure, temperature and fluid salinity, at least at relatively low Cl concentrations (<12 wt% NaCl equivalent). The values of D Cl fluid/melt drop by approximately a factor of 3 in response to the addition of 20–25 mol% CO 2 to the fluid phase due to the decreased ability of the fluid to hydrate NaCl ion pairs. A new empirical equation describing wt%-based D Cl fluid/melt is derived: l n [ D C l f l u i d / m e l t ] = 1.419 ± 0.048 ∗ l n P + 0.912 ± 0.031 ∗ l n C C l f l u i d + 1.434 ± 0.260 + 4547 ± 443 T - 4.026 ± 0.155 ∗ X C O 2 - 9.790 ± 0.440 which expresses D Cl fluid/melt as a function of pressure (in MPa), temperature (in Kelvins), and the equilibrium concentration of Cl (in wt%) and CO 2 (as molar fraction) in the fluid. The average absolute percentage error of the model predictions relative to the experimental data is 7.3%. The equation contains only monotonous functions to allow moderate extrapolation outside the range of the calibration dataset as long as the fluid remains in the single-phase field (e.g. pressure above 100 MPa and up to 500 MPa or even higher). Our model equation represents a reasonable approximation for granitoid magma evolution in the upper and middle crust. The presence of CO 2 suppresses fluid salinity at a given chloride content of a granitoid melt, which will also hinder the extraction of chloride-complexed ore metals (e.g. Cu, Pb, Zn, Mo, and Ag) into magmatic fluids, reducing the likelihood of base-metal ore formation (e.g. porphyry copper deposits) from such fluids in the uppermost crust. On the other hand, the highly volatile components, CO 2 , H 2 S and SO 2 , are enriched in magmatic fluids exsolving early during the ascent of hydrous magmas. Chloride suppression by CO 2 and enrichment of fluids in sulfur species near the SO 2 /H 2 S predominance boundary favors extraction of sulfide-complexed metals, notably Au as Au(HS)0, Au(HS) 2 −, NaAu(HS) 2 0 or Au(HS)S 3 − into low-salinity magmatic fluids. Such fluids resemble those forming mid-crustal lode gold deposits that are typically poor in base metals. Our experimental results may therefore be taken as indirect support for a magmatic component in fluids forming orogenic lode gold deposits. [ABSTRACT FROM AUTHOR]

Determining the composition of natural fluids exsolved from magmas at depth is crucial for our understanding of volcanic degassing processes and the formation of magmatic-hydrothermal ore deposits. Here, we analyzed (a) co-existing melt and vapor-like fluid inclusions, (b) co-existing brine and vapor-like inclusions, and (c) pure end-member assemblages, using LA-ICP-MS. Inclusions hosted in quartz were most suitable for analysis due to quartz being a physically strong container and a relatively pure mineral. To evaluate effects of diffusion through the crystal lattice, inclusions hosted in feldspar were also analyzed. In contrast to previous studies targeting the magmatic-hydrothermal transition (e.g. Zhang & Audétat, 2018), the silicate melt inclusions analyzed here were glassy and did not require re-homogenization. Silicate melt inclusions from rhyolitic pumice samples from the Kos Plateau Tuff (e.g. Allen et al., 1999) show very little variability in major and trace element composition both within single assemblages and across different assemblages. In contrast, those from in granitic clasts that formed co-genetically with the KPT pumices (e.g. Bachman, 2010) display more heterogeneous compositions even within assemblages and a late-stage fractionation trend with extreme enrichment of some incompatible elements such as Cs, B, W and As, suggesting entrapment at crystallinities of up to > 99 %. Fluid inclusions were observed only in co-genetic granites. According to microthermometric studies, these fluids were entrapped at near-magmatic temperatures (total homogenization of brine inclusions at > 500 °C). Brines have a salinity of ca. 35-50 wt% NaClequiv and contain 1-4 solid crystals. Vapor-like inclusions co-existing with silicate melt inclusions (vapor-1) are denser (ca. 20-40 vol% liquid), tend to be healed better, and display a larger range of salinities (ca. 3-15 wt% NaClequiv) than those co-existing with brine inclusions (vapor-2). CO2 was detected by Raman spectroscopy in some vapor-like inclusion assemblages, but never in those coexisting with silicate melt inclusions, making it unlikely that vapor-2 resulted directly from boiling of vapor-1. Analysis of co-existing silicate melt and intermediate-density fluid inclusions revealed a preference of the elements Cu, As, and Pb for the vapor phase, while the elements Rb, Cs, Na, and K preferred the melt phase. The elements B, Mn, Fe, and W scatter around unity. All other elements were below detection limit (in the vapor phase). Between a low-density vapor and a brine, most elements including Cu prefer the brine and only B clearly partitions into the vapor phase. The elements Sn, As, and Zn scatter around unity. These results are assumed to be representative for very evolved, subduction-zone-related magmatic suites without high F concentrations. [ABSTRACT FROM AUTHOR]

The Prominent Hill deposit is a world-class iron oxide copper–gold (IOCG) deposit in South Australia, characterized by a high Cu/S ratio of the dominant Cu-(Fe) sulfides hosted by hematite breccias. It contains a total resource of 278 Mt of ore at 0.98% Cu and 0.75 g/t Au. Prominent Hill is one of several IOCG deposits and numerous prospects in the Olympic IOCG province that are temporally associated with the 1603–1575 Ma Gawler Range Volcanics, a large igneous province including co-magmatic granitoid intrusions of the Hiltaba Suite. Globally, IOCG deposits share many similar features in terms of their geological environment and mineral association. However, it is not yet clear whether sulfur and copper originate from the same source rocks and which hydrothermal redox processes created the characteristic iron oxide enrichment. Highly variable sulfur isotope compositions of sulfides and sulfates in IOCG deposits have previously been interpreted in terms of diverse sulfur sources that may include contributions from magmatic, sedimentary, seawater or evaporitic sulfur. In order to test these alternatives, we performed a detailed sulfur isotope study of Cu-(Fe) sulfides from Prominent Hill and IOCG prospects nearby. The Prominent Hill deposit shows a wide range in δ 34 S V-CDT between − 33.5‰ and 29.9‰ for Cu-(Fe) sulfides, and a narrower range of 4.3‰ to 15.8‰ for barite. Iron sulfides (pyrite, pyrrhotite) show a narrow range in sulfur isotope composition, whereas Cu-bearing sulfides show a much wider range, and more negative δ 34 S V-CDT values on average. We propose a two-stage sulfide mineralization model for the IOCG system in the Prominent Hill area, in which all hydrothermal sulfur is ultimately derived from a magmatic source that had a composition of 4.4 ± 2‰. The diversity in sulfur isotope composition can be produced by different fluid evolution pathways along reducing or oxidizing trajectories. A reduced sulfur evolution pathway is responsible for stage I mineralization, when intrusion-derived magmatic-hydrothermal fluids produced early pyrite and minor chalcopyrite at Prominent Hill, and iron ± copper sulfides in regional magnetite skarns and in some pervasively altered volcanic rocks of the Gawler Range Volcanics. Shallow-venting magmatic-hydrothermal fluids and subaerial volcanic gases that became completely oxidized by reaction with atmospheric oxygen produced sulfate and sulfuric acid with a sulfur isotope composition equal to their magmatic source. This highly oxidized ore fluid probably consisted dominantly of water from the hydrosphere, but contained magmatic solute components, notably sulfate, acidity and Cu. Sulfate reduction produced hydrothermal Cu sulfides with a wide range in sulfur isotope compositions from very negative to moderately positive values. Partial reaction of the Cu-rich stage II fluid with earlier stage I sulfides resulted in mixing of sulfur derived from sulfate reduction and from sulfides deposited during stage I. Modeling of the sulfur isotope fractionation processes in response to reducing and oxidizing pathways demonstrates that the entire spectrum of sulfur isotope data from stage I and stage II mineralization can be explained with a single, ultimately magmatic sulfur source. Such a magmatic sulfur source is also adequate to explain the complete spectrum of sulfur isotope data of other IOCG prospects and deposits in the Olympic province, including Olympic Dam. The results of our study challenge the conventional model that suggests the requirement of multiple and compositionally diverse sulfur sources in hematite-breccia hosted IOCG style mineralization. [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]

Bridging the gap between the plutonic and volcanic realms is essential for understanding a variety of magmatic processes from calderaforming eruptions to the formation of magmatic-hydrothermal ore deposits. Porphyry copper deposits are commonly associated with large and long-lived volcanic centers, but the temporal and dynamic link between mineralized intrusions and volcanic eruptions has remained controversial. Based on the combination of (1) high-precision zircon U-Pb geochronology and trace element geochemistry with (2) plagioclase textures, we discovered an intimate connection between an ignimbrite eruption and a nearby world-class porphyry deposit (Bajo de la Alumbrera in the late Miocene Farallón Negro Volcanic Complex of Argentina). Our results indicate that the magmatic-hydrothermal deposit and explosive volcanism were derived from a common magma reservoir that evolved over a minimum duration of 217 ± 25 k.y. before the final eruption. We show that the volcanic pile represents the inverted magma reservoir, recording systematic differences in plagioclase textures and juvenile clast content from bottom to top. This tight temporal and geochemical link suggests that deposit formation and volcanic eruption were both triggered by the same injection of a volatile-saturated primitive magma into the base of the magma chamber. A time gap of 19 ± 12 k.y. between porphyry mineralization and the onset of explosive volcanism indicates a minimum duration of magma reservoir rejuvenation that led to the explosive eruptive event. Catastrophic loss of volatiles by explosive volcanism terminated the ore-forming capacity of the upper-crustal magma chamber, as evidenced by the intrusion of a syn-eruptive barren quartz-feldspar porphyry. Our results demonstrate that porphyry copper deposits provide critical information to understand how volatiles control the fate of hydrous magmas between pluton formation and explosive volcanism. [ABSTRACT FROM AUTHOR]