Die Petrographie keramischer Grabbeigaben und Steinwerkzeuge aus der Deltaebene des Mekong

In den vergangenen Jahren hat die Kommission für Archäologie Außereuropäischer Kulturen des Deutschen Archäologischen Instituts Grabungsprojekte auf eisenzeitlichen Gräberfeldern der Prä-Funan-Kultur (500 v. bis 200 n. Chr.) in der Tiefl andebene des Mekong sowohl in Kambodscha (Prohear, Provinz Prey Veng) als auch in Südvietnam (Gò Ô Chùa, Provinz Long An) durchgeführt. Dabei wurden neben vielen Grabbeigaben aus Bronze, Eisen, Gold und Glas auch umfangreiche Keramik-Kollektionen und zahlreiche Gesteinsartefakte geborgen. Im unmittelbaren Umfeld der untersuchten Fundplätze stehen keine Festgesteine an. Aus Mangel an Steinrohstoffen hat die Bevölkerung benachbarter eisenzeitlicher Siedlungen Werkzeuge wie Beile sogar aus Muschelschalen oder Schildkrötenpanzer hergestellt (Reinecke 2012: 241, Anm. 2). Eine Untersuchung beider Materialgruppen unter petrographischen Gesichtspunkten verspricht Einblicke in die Rohstoff-Beschaffung beider Orte. Da die beiden Fundplätze Prohear und Gò Ô Chùa nur 65 km Luftlinie voneinander entfernt liegen, ist es darüber hinaus interessant, den Unterschieden oder Gemeinsamkeiten der Steinrohstoffe und des Tonmaterials beider Gemeinschaften nachzugehen (Abb. 1). Speziell bei der Keramik beider Fundstellen, die in Form, Farbe und Verzierung viele Übereinstimmungen zeigt, werden petrographische Untersuchungen auch mit zur Aufklärung beitragen, ob beispielsweise zwei unterschiedliche „Dorf-Töpfereien“ nach gleicher Tradition gearbeitet haben oder ob beide Gemeinschaften von einer oder mehreren zentralen Töpfereien beliefert worden sind

Auf der Suche nach dem passenden Rohstoff – Lithische Grabbeigaben und ihre Herkunft in der Deltaebene des Mekong

Die Deltaebene des Mekong in Südvietnam und Kambodscha wird von mächtigen alluvialen Sedimentschichten aufgebaut. Die Landschaft ist morphologisch flach und nur wenige reliktische Inselberge aus Festgesteinen erheben sich als Härtlinge aus der Landschaft (Abb. 1). Für die Bevölkerung vorgeschichtlicher Siedlungen stand also nur eine begrenzte Anzahl widerstandsfähiger, fester Rohstoffe zur Verfügung, um Werkzeuge für das alltägliche Leben wie zum Beispiel Beile, Mörser, Stößel, Schab- und Schleifsteine herzustellen. Dennoch wurden bei archäologischen Grabungen auf eisenzeitlichen Gräberfeldern der Prä-Funan-Kultur (400 v. bis 100 n. Chr.) in den letzten Jahren neben reichhaltigen Grabbeigaben aus Bronze, Eisen, Gold und Glas sowie vielfältigen Keramikkollektionen auch zahlreiche Gesteinsartefakte unterschiedlichster Genese geborgen (Reinecke et al. 2009). Dies deutet darauf hin, dass bereits fertige Werkzeuge oder entsprechende Rohstoffe aus dem ferneren Umland importiert wurden. Aufgrund des begrenzten Spektrums an natürlich vorkommenden Festgesteinsaufschlüssen in der Tiefl andebene des Mekong stellt sich die Frage, ob anhand einer gezielten Beprobung der Gesteinsvorkommen eine Zuordnung der genutzten Gesteinswerkstoffe zu ihrer ursprünglichen Herkunftsregionen erfolgen kann. Um dieser Fragestellung nachzugehen, hat die Kommission für Archäologie Außereuropäischer Kulturen des Deutschen Archäologischen Instituts im Jahr 2015 ein Forschungsstipendium vergeben. Ziel der Forschungsarbeiten ist es, mögliche Rohstoffquellen in der Deltaebene des Mekong zu identifi zieren und diese anhand geochemisch-petrographischer Untersuchungen mit den in Kambodscha (Prohear, Provinz Prey Veng) und Südvietnam (Gò Ô Chùa, Provinz Long An) bei Grabungen des Deutschen Archäologischen Instituts geborgenen Artefakten abzugleichen. Hierdurch soll die Rekonstruktionvon Handelsrouten sowohl für die erforderlichen Rohstoffe als auch für die bereits gefertigten Werkzeuge ermöglicht werden

Ground truthing global-scale model estimates of groundwater recharge across Africa

Groundwater is an essential resource for natural and human systems throughout the world and the rates at which aquifers are recharged constrain sustainable levels of consumption. However, recharge estimates from global-scale models regularly disagree with each other and are rarely compared to ground-based estimates. We compare long-term mean annual recharge and recharge ratio (annual recharge/annual precipitation) estimates from eight global models with over 100 ground-based estimates in Africa. We find model estimates of annual recharge and recharge ratio disagree significantly across most of Africa. Furthermore, similarity to ground-based estimates between models also varies considerably and inconsistently throughout the different landscapes of Africa. Models typically showed both positive and negative biases in most landscapes, which made it challenging to pinpoint how recharge prediction by global-scale models can be improved. However, global-scale models which reflected stronger climatic controls on their recharge estimates compared more favourably to ground-based estimates. Given this significant uncertainty in recharge estimates from current global-scale models, we stress that groundwater recharge prediction across Africa, for both research investigations and operational management, should not rely upon estimates from a single model but instead consider the distribution of estimates from different models. Our work will be of particular interest to decision makers and researchers who consider using such recharge outputs to make groundwater governance decisions or investigate groundwater security especially under the potential impact of climate change

Development of Complex Mathematical Model of Light Naphtha Isomerization and Rectification Processes

The technique of developing a mathematical model of catalytic isomerization of light naphtha is stated Using experimental data from an industrial isomerization unit shows adequacy of the mathematical model to the real process. The paper presents a method for optimizing the operation of the plant together with catalytic isomerization unit and separation columns. Selection of optimal modes of separation columns allows achieving the desired flow separation between units, as well as extension of the life of the catalyst SI-2

Functional relationships reveal differences in the water cycle representation of global water models

Global water models are widely used for policy-making and in scientific studies, but substantial inter-model differences highlight the need for additional evaluation. Here we evaluate global water models by assessing so-called functional relationships between system forcing and response variables. The more widely used comparisons between observed and simulated fluxes provide insight into model behavior for the representative area of an observation, and can therefore potentially improve the model for that area. Functional relationships, by contrast, aim to capture how system forcing and response variables co-vary across large scales, and thus offer the potential for model improvement over large areas. Using 30-year annual averages from 8 global water models, we quantify such functional relationships by calculating correlations between key forcing variables (precipitation, net radiation) and water fluxes (actual evapotranspiration, groundwater recharge, total runoff). We find strong disagreement for groundwater recharge, some disagreement for total runoff, and the best agreement for evapotranspiration. Observation- and theory-derived functional relationships show varying agreements with models, indicating where model representations and our process understanding are particularly uncertain. Overall, our results suggest that model improvement is most important for the representation of energy balance processes, recharge processes, and generally for model behavior in dry and cold regions. We argue that advancing our ability to simulate global hydrology requires a better perceptual understanding of the global water cycle. To evaluate if our models match that understanding, we should explore alternative evaluation strategies, such as the use of functional relationships

A roadmap to improve the quality of atrial fibrillation management:proceedings from the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference

At least 30 million people worldwide carry a diagnosis of atrial fibrillation (AF), and many more suffer from undiagnosed, subclinical, or 'silent' AF. Atrial fibrillation-related cardiovascular mortality and morbidity, including cardiovascular deaths, heart failure, stroke, and hospitalizations, remain unacceptably high, even when evidence-based therapies such as anticoagulation and rate control are used. Furthermore, it is still necessary to define how best to prevent AF, largely due to a lack of clinical measures that would allow identification of treatable causes of AF in any given patient. Hence, there are important unmet clinical and research needs in the evaluation and management of AF patients. The ensuing needs and opportunities for improving the quality of AF care were discussed during the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference in Nice, France, on 22 and 23 January 2015. Here, we report the outcome of this conference, with a focus on (i) learning from our 'neighbours' to improve AF care, (ii) patient-centred approaches to AF management, (iii) structured care of AF patients, (iv) improving the quality of AF treatment, and (v) personalization of AF management. This report ends with a list of priorities for research in AF patients

On the evaluation of climate change impact models

In‐depth understanding of the potential implications of climate change is required to guide decision‐ and policy‐makers when developing adaptation strategies and designing infrastructure suitable for future conditions. Impact models that translate potential future climate conditions into variables of interest are needed to create the causal connection between a changing climate and its impact for different sectors. Recent surveys suggest that the primary strategy for validating such models (and hence for justifying their use) heavily relies on assessing the accuracy of model simulations by comparing them against historical observations. We argue that such a comparison is necessary and valuable, but not sufficient to achieve a comprehensive evaluation of climate change impact models. We believe that a complementary, largely observation‐independent, step of model evaluation is needed to ensure more transparency of model behavior and greater robustness of scenario‐based analyses. This step should address the following four questions: (1) Do modeled dominant process controls match our system perception? (2) Is my model's sensitivity to changing forcing as expected? (3) Do modeled decision levers show adequate influence? (4) Can we attribute uncertainty sources throughout the projection horizon? We believe that global sensitivity analysis, with its ability to investigate a model's response to joint variations of multiple inputs in a structured way, offers a coherent approach to address all four questions comprehensively. Such additional model evaluation would strengthen stakeholder confidence in model projections and, therefore, into the adaptation strategies derived with the help of impact models.A comprehensive evaluation of climate change impact models combining both observation‐based and response‐based strategies.This article is categorized under: Climate Models and Modeling > Knowledge Generation with Models Assessing Impacts of Climate Change > Evaluating Future Impacts of Climate ChangeAlexander von Humboldt‐Stiftung http://dx.doi.org/10.13039/100005156Engineering and Physical Sciences Research Council http://dx.doi.org/10.13039/50110000026