Endoscopic hemostasis state of the art - nonvariceal bleeding

New endoscopic techniques for hemostasis in nonvariceal bleeding were introduced and known methods further improved. Hemospray and Endoclot are two new compounds for topical treatment of bleeding. Initial studies in this area have shown a good hemostatic effect, especially in active large scale oozing bleeding, e.g., tumor bleedings. For further evaluation larger prospective studies comparing the substanced with other methods of endoscopic hemostasis are needed. For localized active arterial bleeding primary injection therapy in the area of ​​bleeding as well as in the four adjacent quadrants offers a good method to reduce bleeding activity. The injection is technically easy to learn and practicable. After bleeding activity is reduced the bleeding source can be localized more clearly for clip application. Today many different through-the-scope (TTS) clips are available. The ability to close and reopen a clip can aid towards good positioning at the bleeding site. Even more important is the rotatability of a clip before application. Often multiple TTS clips are required for secure closure of a bleeding vessel. One model has the ability to use three clips in series without changing the applicator. Severe arterial bleeding from vessels larger than 2 mm is often unmanageable with these conventional methods. Here is the over-the-scope-clip system another newly available method. It is similar to the ligation of esophageal varices and involves aspiration of tissue into a transparent cap before closure of the clip. Thus a greater vascular occlusion pressure can be achieved and larger vessels can be treated endoscopically. Patients with severe arterial bleeding from the upper gastrointestinal tract have a very high rate of recurrence after initial endoscopic treatment. These patients should always be managed in an interdisciplinary team of interventional radiologist and surgeons

The geographies of ancient Ephesus and the Artemision in Anatolia

WOS: 000243163500007This study is a sedimentologic and geomorphologic analysis of ancient geographies of the floodplains and delta of the Kucuk Menderes (ancient Cayster River) around the city of Ephesus and the Artemision in Aegean coastal Anatolia. The authors emphasize the interrelationship of archaeological dating and structure, and historical comment in interdisciplinary analysis of ancient geographies and their paleoenvironments. In some cases, the historical literature is specific and factual. In other cases, legend from prehistory may provide important clues to the reconstruction of ancient environments as related to archaeological and historical settings. Ephesus and the closely related Artemision, or Temple of Diana of the Ephesians, offer a chance to link the disciplines of geology, physical geography, archaeology, history, and epigraphy in a composite of paleoenvironmental/paleogeographical interpretations of geomorphology over the past three millennia. Holocene sea-level rise and marine transgression provide the raised paralic settings of the harbors of Ephesus and the Artemision. The settings of the harbors were altered by continuing progradation of the ancient Cayster River delta-floodplain over the past three millennia. This research shows how interdisciplinary research greatly enhances our understanding of the ancient geographies of Ephesus and the Artemision. (c) 2007 Wiley Periodicals, Inc

Towards increasing the spatial resolution of luminescence chronologies - Portable luminescence reader measurements and standardized growth curves applied to a beach-ridge plain (Phra Thong, Thailand)

Since optically stimulated luminescence (OSL) dating is time-consuming and cost-intensive, the quantity of ages available for individual study sites is usually restricted significantly. In particular the interpretation of complex depositional systems with temporally and spatially diverse sedimentation histories may suffer from the effects of a poor spatial resolution or an ineffective distribution of chronological data. In these cases, time and cost efficient approaches that provide reasonable dating accuracy are required to substitute or complement full luminescence dating. In this study, we evaluate the potential (i) of luminescence profiling using a portable luminescence reader, and (ii) of standardized growth curves applied to quartz extracts and bulk samples in a standard luminescence reader for functioning as age proxies. Since both proxies save time for processing and/or measurements, they would be applicable to larger datasets in future studies and, by this, may allow to improve the spatial resolution and sampling strategy of OSL dating in coastal settings. Both approaches are applied to a set of approximately 50 samples from the sandy beach-ridge plain of Phra Thong Island, Thailand, for which age control is given by regular quartz luminescence dating from previous studies. Results show that although standardized growth curves are also associated with shortcomings in dating accuracy, and luminescence profiling in general does not equal full luminescence dating, both approaches are capable of reproducing some of the main chronostratigraphic features of the island. This includes the differentiation between the Holocene and Last Interglacial parts of the ridge plain, as well as the identification of the general east-west pro gradation of the Holocene ridges. On the other hand, several pronounced hiatuses of 1500-2000 years within the Holocene sediment succession, were not identified at all or with a poor precision. More robust absolute age estimates can only be achieved by considering the highly variable dosimetry, which is the main contributing factor to bulk luminescence signals apart from deposition age on Phra Thong Island. Thus, for the beach ridges on Phra Thong portable reader signals as a proxy for palaeodoses combined with sample-specific dose rates seem to be the best compromise between rapid data acquisition and adequate dating accuracy. In future studies, this will allow for processing significantly larger numbers of samples compared to regular luminescence dating while keeping dating accuracy at a level that should be adequate for many research questions, which in the end could enable an increased spatial resolution of chronological information. (C) 2016 Elsevier B.V. All rights reserved

Migration of Barchan Dunes in Qatar-Controls of the Shamal, Teleconnections, Sea-Level Changes and Human Impact

Barchan dune fields are a dominant landscape feature in SE Qatar and a key element of the peninsula's geodiversity. The migration of barchan dunes is mainly controlled by dune size, wind patterns, vegetation cover and human impact. We investigate the variability of dune migration in Qatar over a time period of 50 years using high-resolution satellite and aerial imagery. We then explore its relation to the regional Shamal wind system, teleconnection patterns, and limitations in sand supply associated with the transgression of the Arabian Gulf. Strong size-dependent differences in migration rates of individual dunes as well as significant decadal variability on a dune-field scale are detected, which are found to correlate with the intensity of the North Atlantic Oscillation (NAO) and the Indian Summer Monsoon (ISM), in particular during years of relatively strong (weak) summer Shamals. High uncertainties associated with the extrapolation of migration rates back into the Holocene, however, do not permit further examination of the timing of the loss of sand supply and the onset of the mid-Holocene relative sea-level (RSL) highstand. For the youngest phase considered in this study (2006-2015), human impact has likely accelerated dune migration under a weakening Shamal regime through sand mining and excessive vehicle traffic upwind of the core study area

Do mythological traditions reflect past geographies? The Acheloos delta (Greece) and the Artemision (Turkey) case studies

This paper presents results from palaeogeographical studies carried out in the southeastern Acheloos River delta, northwestern Greece, and in the vicinity of the Artemision, western Turkey, and focuses on the question to what extent mythological traditions may document past palaeoenvironmental settings. The landscape reconstructions are based on the study of near-coast sediments recovered by terrestrial vibracoring or lake coring from a universal sampling platform. Sediment cores underwent sedimentological, geochemical, microfaunal and micromorphological analyses. C-14-AMS ages and diagnostic ceramic fragments were used to establish local geochronologies. Geophysical studies helped to set up palaeogeographical maps for different points in time. Palaeogeographical scenarios were then compared with mythological traditions as documented by ancient accounts and archaeological evidence. Our results show that the famous battle between Heracles and the ancient river god Acheloos may symbolize a major diversion of the Acheloos River dating to the late 2(nd) millennium BC. The Artemision, one of the Seven Wonders of the Ancient World, today lies some 9 km inland. Our study revealed thick littoral deposits below its foundation; this is consistent with the legend that the Artemision was erected at a place where once a tree trunk in the form of a female body had been stranded on the beach. Further possible relations between landscape evolution and mythological traditions are discussed for both case studies. It remains, however, impossible to provide a definite scientific basis for the mentioned myths

Using R for TL dating

Whilst optically stimulated luminescence (OSL) is commonly more suitable for sediment dating because of faster signal resetting, thermoluminescence (TL) remains important for dating burnt material, e.g. in archaeological contexts, or for studying the luminescence properties of different materials. A lack of user-optimized analysis software for TL data has exacerbated the decline of TL dating in comparison to OSL. However, exciting developments in TL dating of flint and calcite indicate a rise in application of this underused method. R is a programming language and environment for statistical computing and graphics. It provides a wide variety of statistical and graphical techniques and is highly extendable. A package specifically designed for luminescence data analysis is available. However, it mainly includes functions for the analysis of OSL data. The TLdating package is a new R package specifically dedicated to TL dating. This package is designed to be fully compatible with the existing Luminescence package and is user-friendly. It includes functions for TL data pretreatment and palaeodose estimation using the MAAD and the SAR protocols. The functionality of the TLdating package is evaluated using heated flints from Taibeh, Jordan. (C) 2016 Elsevier B.V. All rights reserved