540 research outputs found

    Low-temperature thermochronology and thermokinematic modeling of deformation, exhumation, and development of topography in the central Southern Alps, New Zealand

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    Apatite and zircon (U-Th)/He and fission track ages were obtained from ridge transects across the central Southern Alps, New Zealand. Interpretation of local profiles is difficult because relationships between ages and topography or local faults are complex and the data contain large uncertainties, with poor reproducibility between sample duplicates. Data do form regional patterns, however, consistent with theoretical systematics and corroborating previous observations: young Neogene ages occur immediately southeast of the Alpine Fault (the main plate boundary structure on which rocks are exhumed); partially reset ages occur in the central Southern Alps; and older Mesozoic ages occur further toward the southeast. Zircon apparent ages are older than apatite apparent ages for the equivalent method. Three-dimensional thermokinematic modeling of plate convergence incorporates advection of the upper Pacific plate along a low-angle detachment then up an Alpine Fault ramp, adopting a generally accepted tectonic scenario for the Southern Alps. The modeling incorporates heat flow, evolving topography, and the detailed kinetics of different thermochronometric systems and explains both complex local variations and regional patterns. Inclusion of the effects of radiation damage on He diffusion in detrital apatite is shown to have dramatic effects on results. Geometric and velocity parameters are tuned to fit model ages to observed data. Best fit is achieved at 9 mm a−1 plate convergence, with Pacific plate delamination on a gentle 10°SE dipping detachment and more rapid uplift on a 45–60° dipping Alpine Fault ramp from 15 km depth. Thermokinematic modeling suggests dip-slip motion on reverse faults within the Southern Alps should be highest ∼22 km from the Alpine Fault and much lower toward the southeast

    Taxes and fees of regional water authorities in the Netherlands

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    The Dutch water management system is fairly unique in the world due to the comprehensive water quantity regulation through dykes and artificial waterways and its linkage with water quality regulation. The existing levy system is based on principles of cost recovery and ‘stakepay-say’ (i.e. strong stakeholder participation and more influence for those who pay levies). The peculiarities of the levy base clearly had a strong impact on businesses’ behaviour in the past, investing in their own water treatment plants to avoid payment of levies. Moreover, the levy also seems to have contributed to innovation in the waste water treatment sector. Although the Dutch water levy system seems to be working quite well, as identified in a 2014 OECD report there remain opportunities for further improvement and an evaluation of the system is currently underway

    Modeling the current distribution in HTS tapes with transport current and applied magnetic field

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    A numerical model is developed for the current distribution in a high temperature superconducting (HTS) tape, (Bi,Pb)2Sr2 Ca2Cu3Ox-Ag, subjected to a combination of a transport current and an applied magnetic field. This analysis is based on a two-dimensional formulation of Maxwell's equations in terms of an integral equation for the current density J. The finite thickness of the conductor and an arbitrary voltage-current relation (e.g. n-power relation, magnetic field dependency) for the conductor are included in the model. Another important feature is that the model also covers an applied magnetic field in arbitrary directions and a rotating field perpendicular to the conductor, which is of great interest for analyzing the AC loss of HTS (transformer) coils or three-phase electric power cables. A comparison is made with transport current loss measurements on an HTS tape with an AC applied fiel

    The fate of intertidal microphytobenthos carbon: an in situ <sup>13</sup>C-labeling study

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    At two intertidal sites (one sandy and one silty, in the Scheldt estuary, The Netherlands), the fate of microphytobenthos was studied through an in situ 13C pulse- chase experiment. Label was added at the beginning of low tide, and uptake of 13C by algae was linear during the whole period of tidal exposure (about 27 mg m-2 h-1 in the top millimeter at both sites). The 13C fixed by microphytobenthos was rapidly displaced toward deeper sediment layers (down to 6 cm), in particular at the dynamic, sandy site. The residence times of microphytobenthos with respect to external losses (resuspension and respiration) were about 2.4 and 5.6 d at the sandy and silly stations, respectively. The transfer of carbon from microphytobenthos to benthic consumers was estimated from the appearance of 13C in bacterial biomarkers, handpicked nematodes, and macrofauna. The incorporation of 13C into bacterial biomass was quantified by carbon isotope analysis of polar lipid derived fatty acids specific for bacteria. The bacterial polar lipid-derived fatty acids (i14:0, i15:0, a15:0, i16:0, and 18:1 omega 7c) showed rapid, significant transfer from benthic algae to bacteria with maximum labeling after 1 d. Nematodes became enriched after 1 h, and 13C assimilation increased until day 3. Microphytobenthos carbon entered all heterotrophic components in proportion to heterotrophic biomass distribution (bacteria > macrofauna > meiofauna). Our results indicate a central role for microphytobenthos in moderating carbon flow in coastal sediments

    Інтертекстуальність та гіпертекстуальні трансформації в турецьких народних оповідях

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    In this paper, some of the Turkish minstrel tales are analyzed in the frame of Gérard Genette’s ‘palimpsests’ approach. In the transtextuality category; the minstrel tales demonstrate both intertextual relations and hypertextual transformations. In terms of intertextuality, the tales present self-conscious intertextual relations by referring to other texts. The paper focuses on that in terms of hypertextuality, the mistrel tales transform the other texts by the process of reduction, extension, amplification and so on. Because of this process, the structure, the plot and the meaning of the previous text is transformed. As a result, the Turkish minstrel tales, as oral literary texts, can actively have role in intertextual relations as hypertexts.Türk halk hikâyelerine Fransız anlatıbilimci Gérard Genette’in “palempsest” imgesi ile yaklaşıldığında, halk hikâyelerinin ötemetinsellik sınıflandırmasında “metinlerarasılık” ve “ana metinsellik” ilişkilerini yansıttıkları görülmektedir. Halk hikâyeleri, göndermeler yoluyla bir başka metni somut olarak içinde barındırarak metinlerarasılık ilişkisi kurmaktadır. Bunun yanında, diğer sözlü ve yazılı metinleri biçimsel ve izleksel ya da anlamsal olarak dönüştürerek anlatısını yeniden kompoze etmek noktasında ana metinsellik ilişkisini kurmaktadır. Bu çalışmada Türk halk hikâyelerinin ana metinsellik dönüşümleri biçimsel ve anlamsal dönüşümler yoluyla incelenecektir. Türk halk hikâyeleri odağında yapılan çalışmalarda, genellikle kaynak ve etki alanı arayışları ile karşılaştırmalı eleştiri yaklaşımından yararlanılmıştır. Türk halk hikâyelerine metinlerarasılık ile yaklaşmak, anlatıların anlamsal ve yapısal olarak nasıl katmanlaştığını görmek ve anlatıyı metin olarak çözümlemek açısından somut veriler sağlayan bir yöntemdir

    Schistosomiasis and cancer: experience from a zonal hospital in Tanzania and opportunities for prevention

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    Abstract Schistosomiasis infection is endemic in many parts of Tanzania. The morbidity due to Schistosomiasis and its association with cancer remains to be of great concern and poses greater challenge that needs to be assessed. Cancer is an increasing public health problem in most sub-Saharan African countries, and yet, cancer control programs and the provision of early detection and treatment services are limited despite this increasing burden. This article aims to discuss case series of patients diagnosed with urinary bladder, prostate and colorectal cancer together with Schistosoma infection. We further highlight the opportunities for combating new Schistosomiasis infection, a potential to reduce its oncological complications particularly in low-resource setting

    Restoration of estuarine tidal mudflat sediments after hypoxia

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    Ecosystem function recovery and benthic community recovery was investigated after experimentally induced depleted oxygen bottom water concentrations in a tidal mudflat (Paulinapolder, Westerschelde estuary). Macrofauna recovery developed through different succession stages and was structured by facilitative and inhibitive interactions: early colonizers had a positive effect on subsequent colonizers, while later succession species negatively affected the stable conditions created by the early colonizing tube-builders. Transitions between different stages were related to changes in environmental characteristics and biotic-environmental interactions (e.g. exploitation competition for food). Nematode community -and biogeochemical recovery were related to macrobenthic succession. Dense polychaete tube aggregations and the development of a fresh diatom bloom, as a result of the low grazing pressure by surface deposit feeding macrofauna during the first stage, stabilized the sediment and thereby enhanced macrobenthic and nematode recruitment success. Bioturbation impact of later succession species increased oxygen input in the sediment, resulting in an enhanced nitrification, denitrification and energy use
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