Multi-stage serpentinization of ultramafic rocks in the Manlay Ophiolite, southern Mongolia

Serpentinization of ultramafic rocks in ophiolites is key to understanding the global cycle of elements and changes in the physical properties of lithospheric mantle. Mongolia, a central part of the Central Asian Orogenic Belt (CAOB), contains numerous ophiolite complexes, but the metamorphism of ultramafic rocks in these ophiolites has been little studied. Here we present the results of our study of the serpentinization of an ultramafic body in the Manlay Ophiolite, southern Mongolia. The ultramafic rocks were completely serpentinized, and no relics of olivine or orthopyroxene were found. The composition of Cr-spinels [Mg# = Mg/(Mg + Fe2+) = 0.54 and Cr# = Cr/(Cr + Al) = 0.56] and the bulk rock chemistry (Mg/Si = 1.21–1.24 and Al/Si < 0.018) of the serpentinites indicate their origin from a fore-arc setting. Lizardite occurs in the cores and rims of mesh texture (Mg# = 0.97) and chrysotile is found in various occurrences, including in bastite (Mg# = 0.95), mesh cores (Mg# = 0.92), mesh rims (Mg# = 0.96), and later-stage large veins (Mg# = 0.94). The presence of lizardite and chrysotile and the absence of antigorite suggests low-temperature serpentinization (<300 °C). The lack of brucite in the serpentinites implies infiltration of the ultramafic rocks of the Manlay Ophiolite by Si-rich fluids. Based on microtextures and mineral chemistry, the serpentinization of the ultramafic rocks in the Manlay Ophiolite took place in three stages: (1) replacement of olivine by lizardite, (2) chrysotile formation (bastite) after orthopyroxene and as a replacement of relics of olivine, and (3) the development of veins of chrysotile that cut across all previous textures. The complex texture of the serpentinites in the Manlay Ophiolite indicates multiple stages of fluid infiltration into the ultramafic parts of these ophiolites in southern Mongolia and the CAOB.

Multi-Cycle-Consistent Adversarial Networks for Edge Denoising of Computed Tomography Images

As one of the most commonly ordered imaging tests, the computed tomography (CT) scan comes with inevitable radiation exposure that increases cancer risk to patients. However, CT image quality is directly related to radiation dose, and thus it is desirable to obtain high-quality CT images with as little dose as possible. CT image denoising tries to obtain high-dose-like high-quality CT images (domain Y ) from low dose low-quality CT images (domain X ), which can be treated as an image-to-image translation task where the goal is to learn the transform between a source domain X (noisy images) and a target domain Y (clean images). Recently, the cycle-consistent adversarial denoising network (CCADN) has achieved state-of-the-art results by enforcing cycle-consistent loss without the need of paired training data, since the paired data is hard to collect due to patients’ interests and cardiac motion. However, out of concerns on patients’ privacy and data security, protocols typically require clinics to perform medical image processing tasks including CT image denoising locally (i.e., edge denoising). Therefore, the network models need to achieve high performance under various computation resource constraints including memory and performance. Our detailed analysis of CCADN raises a number of interesting questions that point to potential ways to further improve its performance using the same or even fewer computation resources. For example, if the noise is large leading to a significant difference between domain X and domain Y , can we bridge X and Y with a intermediate domain Z such that both the denoising process between X and Z and that between Z and Y are easier to learn? As such intermediate domains lead to multiple cycles, how do we best enforce cycle- consistency? Driven by these questions, we propose a multi-cycle-consistent adversarial network (MCCAN) that builds intermediate domains and enforces both local and global cycle-consistency for edge denoising of CT images. The global cycle-consistency couples all generators together to model the whole denoising process, whereas the local cycle-consistency imposes effective supervision on the process between adjacent domains. Experiments show that both local and global cycle-consistency are important for the success of MCCAN, which outperforms CCADN in terms of denoising quality with slightly less computation resource consumption.

Marine iodine emissions in a changing world

Iodine is a critical trace element involved in many diverse and important processes in the Earth system. The importance of iodine for human health has been known for over a century, with low iodine in the diet being linked to goitre, cretinism and neonatal death. Research over the last few decades has shown that iodine has significant impacts on tropospheric photochemistry, ultimately impacting climate by reducing the radiative forcing of ozone (O 3 ) and air quality by reducing extreme O 3 concentrations in polluted regions. Iodine is naturally present in the ocean, predominantly as aqueous iodide and iodate. The rapid reaction of sea-surface iodide with O 3 is believed to be the largest single source of gaseous iodine to the atmosphere. Due to increased anthropogenic O 3 , this release of iodine is believed to have increased dramatically over the twentieth century, by as much as a factor of 3. Uncertainties in the marine iodine distribution and global cycle are, however, major constraints in the effective prediction of how the emissions of iodine and its biogeochemical cycle may change in the future or have changed in the past. Here, we present a synthesis of recent results by our team and others which bring a fresh perspective to understanding the global iodine biogeochemical cycle. In particular, we suggest that future climate-induced oceanographic changes could result in a significant change in aqueous iodide concentrations in the surface ocean, with implications for atmospheric air quality and climate.

Income and Labour Market Developments and Social Outcomes in Germany and France

This chapter focuses on France and Germany, the two largest economies of the European Union, comparing recent economic and social developments. It finds that the two economies rely on different growth models, with important social implications. Germany’s postwar economic growth model was strongly based on exports and typically proved more volatile, while gross domestic product (GDP) growth in France was more focused on domestic demand and is usually more stable while on average generating a somewhat lower growth. The flexible German labour market allowed unemployment to decrease, albeit at the expense of higher income poverty and a larger low-wage sector. In France, instead, lower income poverty and a smaller low-wage sector were accompanied by a relatively higher unemployment rate. Recently, the gap between the two growth models and the resulting differences in social outcomes has appeared to be narrowing, reflecting the slowdown in the global cycle and more institutional focus in Germany on inclusiveness and in France on flexibility.

BOOK ANALYSIS WITH THEMA GEOPOLITICS “MEDIA, TERRORISM AND THEORY”, A CRITICAL THEORY RESEARCH APPROACH USING SEMIOTIC ANALYSIS

This article seeks to create a discussion space related to the Media Book, Terrorism and Theory. This book seeks to provide an understanding of the contextualization of the global cycle of violence within the framework of "military action" and "terrorism," as well as mass communication media. The author tries to view this book as a literary work by using semiotic analysis to get the meanings in this book, especially in the sections Critical Media Theory, Democratic Communication, and Global Conflict and Chapter 8 with the title Terrorism, Public Relations and Propaganda. This research finally succeeded in achieving an evaluation that some myths were generated from the meaning of denotation and connotation of Roland Barthes' semiotic technique. These myths when tested through the source triangulation technique show inconsistencies. Some of the myths are discussed by academics and the media, but some do not appear in the media.

Reactivity, fate and functional roles of dissolved organic matter in anoxic inland waters

The transit of organic matter (OM) through the aquatic compartment of its global cycle has been intensively studied, traditionally with a focus on the processing and degradation of its dissolved fraction (dissolved organic matter, DOM). Because this is so intimately related to oxidation, the notion tenaciously persists that where oxygen is absent, DOM turnover is markedly slowed. In this Opinion Piece, we outline how diverse processes shape, transform and degrade DOM also in anoxic aquatic environments, and we focus here on inland waters as a particular case study. A suite of biogeochemical DOM functions that have received comparatively little attention may only be expressed in anoxic conditions and may result in enhanced biogeochemical roles of these deoxygenated habitats on a network scale.

Daily soil carbon dioxide flux under different tillage conditions

Over the last few years, warming of the atmospheric layer near Earth's surface is increasingly experienced and researchers have also established that concentration of numerous greenhouse gases have risen over the past two centuries value. Change is basically a legitimate process - considering atmospheric concentration as well - but the change experienced during the past centuries could not have become this critical without the contribution of human activity. Due to the nature of the greenhouse effect, the result of a very fragile, complex process is experienced currently on Earth, which can be significantly unbalanced even by a slight change. Carbon dioxide emitted from the soil is involved in the global cycle and has an impact on the greenhouse effect. The rise in soil respiration may result in the further intensification of warming. In the scope of the present study, it was examined how carbon dioxide emissions of the soil evolve over a day. The results have been established based on the comparison of the effects of different parts of the day, tillage methods and irrigation.