The role of the fluid composition in the formation of hydrothermal Sn-W ores : insights from in situ analyses of fluid inclusions by UV-fs-LA-ICP-MS

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Petrology, geochemistry and U-Pb geochronology of magmatic rocks from the high-sulfidation epithermal Au-Cu Chelopech deposit, Srednogorie zone, Bulgaria

The Chelopech deposit is one of the largest European gold deposits and is located 60km east of Sofia, within the northern part of the Panagyurishte mineral district. It lies within the Banat-Srednegorie metallogenic belt, which extends from Romania through Serbia to Bulgaria. The magmatic rocks define a typical calc-alkaline suite. The magmatic rocks surrounding the Chelopech deposit have been affected by propylitic, quartz-sericite, and advanced argillic alteration, but the igneous textures have been preserved. Alteration processes have resulted in leaching of Na2O, CaO, P2O5, and Sr and enrichment in K2O and Rb. Trace element variation diagrams are typical of subduction-related volcanism, with negative anomalies in high field strength elements (HFSE) and light element, lithophile elements. HFSE and rare earth elements were relatively immobile during the hydrothermal alteration related to ore formation. Based on immobile element classification diagrams, the magmatic rocks are andesitic to dacitic in compositions. Single zircon grains, from three different magmatic rocks spanning the time of the Chelopech magmatism, were dated by high-precision U-Pb geochronology. Zircons of an altered andesitic body, which has been thrust over the deposit, yield a concordant 206Pb/238U age of 92.21 ± 0.21Ma. This age is interpreted as the crystallization age and the maximum age for magmatism at Chelopech. Zircon analyses of a dacitic dome-like body, which crops out to the north of the Chelopech deposit, give a mean 206Pb/238U age of 91.95 ± 0.28Ma. Zircons of the andesitic hypabyssal body hosting the high-sulfidation mineralization and overprinted by hydrothermal alteration give a concordant 206Pb/238U age of 91.45 ± 0.15Ma. This age is interpreted as the intrusion age of the andesite and as the maximum age of the Chelopech epithermal high-sulfidation deposit. 176Hf/177Hf isotope ratios of zircons from the Chelopech magmatic rocks, together with published data on the Chelopech area and the about 92-Ma-old Elatsite porphyry-Cu deposit, suggest two different magma sources in the Chelopech-Elatsite magmatic area. Magmatic rocks associated with the Elatsite porphyry-Cu deposit and the dacitic dome-like body north of Chelopech are characterized by zircons with ɛHfT90 values of ∼5, which suggest an important input of mantle-derived magma. Some zircons display lower ɛHfT90 values, as low as −6, and correlate with increasing 206Pb/238U ages up to about 350Ma, suggesting assimilation of basement rocks during magmatism. In contrast, zircon grains in andesitic rocks from Chelopech are characterized by homogeneous 176Hf/177Hf isotope ratios with ɛHfT90 values of ∼1 and suggest a homogeneous mixed crust-mantle magma source. We conclude that the Elatsite porphyry-Cu and the Chelopech high-sulfidation epithermal deposits were formed within a very short time span and could be partly contemporaneous. However, they are related to two distinct upper crustal magmatic reservoirs, and they cannot be considered as a genetically paired porphyry-Cu and high-sulfidation epithermal related to a single magmatic-hydrothermal system centered on the same intrusio

Mutationsspektrum, Entstehungsmechanismen und Genotyp-Phänotyp-Beziehungen

Mutationen des RB1-Gens sind ursächlich für die Entstehung des Retinoblastoms, des häufigsten malignen Tumors des Kindesalters. Die Bestimmung der krankheitsursächlichen Veränderung ist bei jedem Patienten für die optimale Betreuung seiner Familie erforderlich. Um Mutationen vom Typ gross deletion effizient zu erkennen, wurde in der vorliegenden Arbeit die quantitative Multiplex-PCR etabliert und mit hier neu entwickelten Methoden zur Bestätigung kombiniert. Die genomische Realtime-PCR und die Longrange-PCR bewährten sich hierbei als geeignete Verfahren. Wir konnten mittels quantitativer Multiplex-PCR bei 61 Patienten gross deletions im RB1-Gen identifizieren (33 konstitutionelle Mutationen und 28 Mutationen in Tumormaterial). Somit konnten wir die Anzahl der publizierten Mutationen dieser Art annähernd verdoppeln. In unserem Patientenkollektiv haben gross deletions einen Anteil von 15% von 443 der konstitutionellen Mutationen bei Patienten mit bilateralem oder familiärem Retinoblastom. Bei isoliert unilateral Betroffenen sind konstitutionelle gross deletions bei 6,1% von 262 festzustellen. Durch die Analyse der Genotyp-Phänotyp-Beziehungen (mit Einschluss von zuvor publizierten Mutationen) konnte hier gezeigt werden, dass gross deletions, die zu vorzeitigen Stopp Kodons führen, die A/B Pocket-Domänen betreffen oder nur einen der Bruchpunkte innerhalb des Gens haben, zu einem schwereren Krankheitsbild führen (größere Zahl von Tumoren) als Ganzgendeletionen oder in-Frame Deletionen ohne Beteiligung der A/B Pocket-Domänen. Eine mögliche Ursache für die mildere phänotypische Ausprägung bei Patienten mit konstitutionellen Ganzgendeletionen – im Vergleich zu Deletionen mit einem Bruch-punkt im RB1-Gen – könnte die Beteiligung von Genen in direkter Nähe zum RB1 sein: Die homozygote Deletion von benachbarten Genen in 5’- und in 3’-Richtung des RB1-Gens könnte zum Zelltod führen und so das Entstehen eines Tumors unterbinden. Die Analyse der Bruchpunktlokalisationen der von uns identifizierten und der zuvor ver-öffentlichten Mutationen zeigte vier Deletions-Bruchpunkt-Cluster im RB1-Gen: Intron 23, 24, 13 und 16. Durch Sequenzanalysen konnten wir zeigen, dass vermutlich Scaffold/Matrix Attached Regions (S/MARs) in Bezug auf die Ursache dieser Bruchpunkthäufungen eine Rolle spielen. Die Integration der hier entwickelten Methodik in die Routine der molekulargenetischen Analyse bei Retinoblastom führt nicht nur zu einer höheren Mutations-Finderate sondern auch zu einer Verkürzug der molekulargenetischen Befunderhebung. Daher bleiben Angehörigen mit Risikoausschluss belastende Untersuchungen früher erspart

Neue/alte Herausforderungen für die grenzübergreifende deutsch-polnische Zusammenarbeit seit Polens Schengen-Beitritt: Słubice und Frankfurt (Oder)

Freizügigkeit als eine der zentralen Errungenschaften der Europäischen Union (EU) ist mittlerweile an vielen internen Grenzen der EU Realität. An der deutsch-polnischen Grenze wurden die permanenten Grenzkontrollen nach dem Schengen Beitritt Polens im Dezember 2007 eingestellt. Während dieser Prozess in der Öffentlichkeit oft als Wegbereiter für die Auflösung der internen EU Grenzen zelebriert wird, beschäftigt sich diese Studie speziell mit den differenzierten Ansichten aktiver Kooperationsakteure für eine grenzüberschreitende langfristige sozio-kulturelle Zusammenarbeit der beiden Grenzstädte Słubice (PL) und Frankfurt (Oder) (D). In dem vorliegenden Aufsatz wird ein fragmentiertes Bild der heutigen Kooperationslandschaft präsentiert. Der Fokus auf Kooperation, persönliche Kontakte und Barrieren zeigt auf, warum der „Entgrenzungsansatz“, welcher mit der Freizügigkeit verbunden war, nicht den erhofften Anstieg der dauerhaften, grenzübergreifenden Aktivitäten mit sich gebracht hat. Dabei spielen neben sozialen Barrieren wie Sprache, kulturelle Unterschiede, tiefgehende Vorurteile und institutionelle Unstimmigkeiten auch ökonomische Aspekte eine Rolle. Die Konsequenzen der „Entgrenzung“ durch die Freizügigkeit werden von den Akteuren in Słubice und Frankfurt (Oder) äußerst unterschiedlich betrachtet. Während bei der deutsch-polnischen Zusammenarbeit eine allgemein positive Entwicklung zu erkennen ist, werfen die Ergebnisse dieser Studie wichtige Aspekte sowie kontroverse Ansichten in Bezug auf die Entwicklung der langfristigen Kooperation auf, welche in zukünftigen Ansätzen und Projekten für grenzübergreifende Arbeit berücksichtigt werden sollten.Freedom of movement, as one of the central achievements of the European Union (EU), has become a reality along most internal EU borders. Incessant border controls on the GermanPolish border ceased after Poland joined the Schengen Area in December 2007. While this process is often celebrated as a pathway to dissolve EU internal borders, this study focuses on the differentiated perspectives of actors actively engaged in long­term, cross­border, socio­cultural cooperation activities between the border towns of Słubice (PL) and Frankfurt (Oder) (D). The study presents a fragmented picture of the current day cooperation environment between the towns. A focus on cooperation, personal contacts and barriers displays why the de­bordering approach, linked to the General Freedom of Movement, has not been accompanied by the expected increase of long-lasting cross-border activities. Aside from social barriers such as language and cultural differences, profound prejudices and institutional discrepancies as well as economic aspects play a role. The actual consequences of the de­bordering process are perceived in various ways by actors from Słubice and Frankfurt (Oder). Considering the positive trend of German­Polish cooperation in general, the results of the study raise important aspects and controversial perspectives in relation to the development of long-lasting cooperation that should be acknowledged in future approaches and projects for cross-border activities

Blue bioeconomy localities at the margins : Reconnecting Norwegian seaweed farming and Finnish small-scale lake fisheries with blue policies

The blue bioeconomy is gaining momentum in EU policy debate and various national government strategies as a pathway towards a more sustainable society. Linked to the circularity of economic processes, it combines the promise of (regional) economic development with a sustainable, bio-based transition focused on increased and novel utilisation of aquatic resources. Nonetheless, portrayed as a holistic approach, the political visions of blue bioeconomy reside predominantly in marine environments with little integration of freshwater perspectives or alternative development paths. Rooted in concepts of policy mobility, assembling processes and the positionalities of involved entities, this paper displays two regionally embedded blue bioeconomy developments – Norwegian coastal seaweed farming and Finnish lake fisheries – and their spatially diverse reconnections with national and international policy narratives. By framing a freshwater and a coastal marine case, and their spatial reconnections with an overarching yet diversely translated policy realm, the paper taps into the multiple ontologies of water in blue bioeconomy governance and presents initial empirical and methodological steps towards a relational understanding of its governance processes. Based on four key topical reconnections, the article points to a variety of challenging mismatches between policy narratives, local development processes and potentials. It also suggests conceptual and methodological implications of this approach for further research into “blue” resource governanc

Quantification of trace element contents in frozen fluid inclusions by UV-fs-LA-ICP-MS analysis

We have developed a new analytical setup for the determination of trace element concentrations in fluid inclusions by UV-fs-LA-ICP-MS. Laser ablation was performed at a low temperature of -40 degrees C by using a modified heating-freezing stage as the ablation cell. With this method it was possible to successfully analyse 53 of 55 frozen synthetic NaCl-H2O fluid inclusions in quartz, covering a size range between 8 mu m and 25 mu m down to a depth of 50 mu m. The high success rate could be achieved as the 194 nm UV-fs-laser allows excellent control over the opening procedure of frozen fluid inclusions. Trace element analyses were performed with a fast scanning magnetic sector field ICP-MS. The lower limits of detection for fluid inclusion analysis vary from 0.1 mu g g(-1) (for Bi-209) to 10 mu g g(-1) (for K-39). The typical analytical uncertainty, depending on the element and respective concentration level, ranges between 10% and 30% (1RSD), based on the reproducibility of experimentally synthesized fluid inclusions. All elements from a stock solution, which behaved inert during the HP/HT experiments (B, K, Cd, Te, Tl, Pb and Bi), could be recovered in the synthetic inclusions at concentrations that correspond within their specific analytical uncertainties to their original concentration of 53 mu g g(-1). The method represents a highly efficient tool for the determination of accurate trace element data on low concentration levels in small fluid inclusions with a high success rate of >90%. The latter is particularly advantageous considering the commonly time consuming characterization of fluid inclusions.NTH Graduate School GeoFluxe

Preoperative Endoscopy and Its Impact on Perioperative Management in Bariatric Surgery

BACKGROUND The role of preoperative upper-gastrointestinal endoscopy for bariatric surgery is still understood only with controversy. The aim of this study was to evaluate the prevalence of endoscopic findings and its impact on perioperative management. METHODS Patients who underwent bariatric surgery at our center between 2010 and 2013 were systematically analyzed from a prospective database. RESULTS Two hundred and twelve patients with a median body mass index of 50 kg/m(2) (range 29-87) underwent 216 bariatric procedures at our center between 2010 and 2013. All patients received preoperative upper endoscopy. In 159 cases (75%), the endoscopy was performed at our center. These cases were included in this study. In 37 cases (23%), no abnormal findings were detected. In 122 cases (76%), upper endoscopy revealed pathologies. No further treatment was necessary in 24 cases (15%). Medical treatment was changed in 81 cases (51%). The operation was delayed due to medical treatment and re-endoscopy in 13 cases (8%). The surgical approach was changed in 4 cases (3%). CONCLUSION Routinely performed preoperative endoscopy before bariatric surgery revealed a high prevalence of gastrointestinal diseases with a significant impact on perioperative management in two thirds of the cases. Therefore, we recommend routine gastroscopy about 2-4 weeks prior to surgery

Increasing the oxidation power of TCNQ by coordination of B(C6F5)3

The oxidation power of the cyanocarbon TCNQ (tetracyano-quinodimethane) can be significantly increased to approximately E = +0.9 V vs. Cp2Fe by coordination of up to four equivalents of the strong fluorinated Lewis acid B(C6F5)3, resulting in a highly reactive but easy-to-use oxidation system. Thianthrene and tris(4-bromophenyl)amine were oxidized to the corresponding radical cations. Dianionic [TCNQ·4 B(C6F5)3]2− was formed upon reduction with two equivalents of ferrocene or decamethylcobaltocene. [TCNQ·4 B(C6F5)3]− and [TCNQ·4 B(C6F5)3]2− are rare cases of redox-active weakly-coordinating anions